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HomeMy WebLinkAbout2022-08-11 PCPPLANNING COMMISSION CITY OF BROOKLYN CENTER REGULAR MEETING AUGUST 11, 2022 Optional public access to the Webex meeting is below: Online: logis.webex.com | Phone: (312) 535-8110 Meeting Number (Access Code): 2453 905 5506 Passcode: BCPC08112022 1. Call to Order – 7 p.m. 2. Roll Call 3. Approval of Agenda a. Motion to Approve Planning Commission Meeting Agenda for August 11, 2022 4. Approval of Minutes a. Motion to Approve June 23, 2022 Meeting Minutes 5. Chairperson's Explanation The Planning Commission is an advisory body. One of the Commission's functions is to hold public hearings. In the matters concerned in these hearings, the Commission makes recommendations to the City Council. The City Council makes all final decisions in these matters. 6. Planning Items a. Planning Commission Application No. 2022-005 (PUBLIC HEARING) Applicant | Property Owner: Joslyn Manufacturing Company LLC Property IDs: 10-118-21-23-0007, 10-118-21-32-0058, and 10-118-21- 32-0059 Summary: The Applicant is requesting issuance of a Special Use Permit for a planned soil remediation project within the designated 100-year floodplain, and as part of continued clean-up efforts for the Joslyn Superfund site. 7. Discussion Items a. City Council Meeting Re-cap b. Upcoming Planning Commission Meetings 8. Adjournment PC Minutes 6/23/22 -1- DRAFT MINUTES OF THE PROCEEDINGS OF THE PLANNING COMMISSION OF THE CITY OF BROOKLYN CENTER IN THE COUNTY OF HENNEPIN AND THE STATE OF MINNESOTA JUNE 23, 2022 1. CALL TO ORDER The Planning Commission meeting was called to order by Vice Chair Omari at 7:30 p.m. The meeting was conducted in-person, with a virtual option via Webex. 2. ROLL CALL Commissioners Paris Dunn, Kau Guannu, Stephanie Jones, and Peter Omari were present. Chair Alexander Koenig (excused) and Commissioner Alfreda Daniels-Juasemai (unexcused) were absent. City Planner and Zoning Administrator Ginny McIntosh and Associate Planner Olivia Boerschinger were also present. 3. APPROVAL OF AGENDA – JUNE 23, 2022 There was a motion by Commissioner Jones, seconded by Commissioner Guannu, to approve the agenda for the June 23, 2022 meeting as presented. Voting on the motion: Vice Chair Omari, Commissioners Dunn, Guannu, and Jones voted aye. The motion passed unanimously. 4. APPROVAL OF MINUTES 4a. January 13, 2022 Regular Meeting Minutes There was a motion by Commissioner Jones, seconded by Commissioner Dunn, to approve the minutes of the January 13, 2022 meeting as presented. Voting on the motion: Vice Chair Omari, Commissioners Dunn, Guannu, and Jones voted aye. The motion passed unanimously. 5. CHAIR’S EXPLANATION Vice Chair Omari explained the Planning Commission’s role as an advisory body. One of the Commission’s functions is to hold public hearings. In the matters concerned in these hearings, the Commission makes recommendations to the City Council. The City Council makes all final decisions in these matters. 6. PLANNING APPLICATION ITEMS PC Minutes 6-23-22 -2- DRAFT 6a. Planning Commission Application No. 2022-004 (PUBLIC HEARING) Applicant: Scannell Properties (on behalf of Transformco) Property Owner: Sears, Roebuck & Company Property Address: 1297 Shingle Creek Crossing (PID 03-118 -21-44-0026) Summary: The Applicant is requesting review and consideration of a proposal to the re-plat and re-develop the approximately 15- acre former Sears site, located at 1297 Shingle Creek Crossing. With the closure of Sears and the adjacent Sears Auto Center in late 2018, the Applicant is proposing the construction of two business park buildings totally 230,000- square feet and related site improvements. City Planner Ginny McIntosh reviewed a request by Scannell Properties, Inc. on behalf of Transformco for consideration of a proposal that would allow for the re-plat and redevelopment of the former Sears site, which is approximately 15 acres and located at 1297 Shingle Creek Crossing. The proposal includes two business park-type buildings and related site improvements. Ms. McIntosh stated Sears was in operation from 1962 until 2018, and is the last remaining remnant of the Brookdale Mall. In late 2020, Sears initiated a formal process to solicit offers from private parties to develop the property. The applicant conducted its own market analysis and worked with local brokers to identify a feasible re-use for the property. Following a Request for Proposals (RFP) in late 2020, a redevelopment partner, Scannell Properties, Inc. was selected. Ms. McIntosh noted since their respective closures, both buildings have had water main breaks, and a major break at the Sears Auto Center in 2019 required issuance of a pumping discharge permit from the Minnesota Pollution Control Agency (MPCA), and water sampling to be conducted for contaminants. Despite the parking lots and entrances having barriers in place, City Staff regularly conduct checks on the buildings due to numerous dumpings and break-ins, which require the buildings to be swept due to life, health, and safety concerns, and re-secured. Ms. McIntosh explained on April 28, 2021, City Council authorized an application to the Metropolitan Council’s Tax Base Revitalization Account (TBRA) for funding to assist with the environmental remediation of the property; however, said application did not move forward in the funding process. A subsequent application to the Environmental Response Fund (ERF) was submitted to Hennepin County in the amount of $163,000, which was awarded for assistance in preparing a Phase I Environmental Site Assessment (ESA), a Phase II ESA, a Response Action Plan, associated consulting activities, and any associated Minnesota Pollution Control Agency (MPCA) fees. Scannell Properties, who specializes primarily in light industrial and commercial business center-type products, subsequently conducted due diligence on the property, including an environmental assessment. As part of this assessment, it was determined there was significant asbestos present that would require remediation prior to any demolition. Ms. McIntosh added a concept review was held with City Council on May 24, 2021, with a follow- PC Minutes 6-23-22 -3- DRAFT up review occurring on November 22, 2021. It was during these reviews that City Council was presented with a proposal to re-develop the Subject Property with a speculative light-industrial and office use. During the May concept review, City Council provided feedback on the initial concept plan, of which included requests to provide a greater mix of uses, a site layout and design that adds value to the adjacent Shingle Creek Crossing shopping center, and an overall high finish level on the buildings, with four-sided architecture, and a focus on enhancing the Highway 100 frontage. Ms. McIntosh showed photos of the existing conditions. Ms. McIntosh stated as proposed, the Applicant intends to re-plat the Subject Property to satisfy lending requirements for separate entities for each building. The existing Registered Land Survey No. 0936, which encompasses the former Sears Department Store, Sears Auto Center, and site improvements, would therefore be re-platted to accommodate the two proposed buildings as Lot 1, Block 1 (approximately 8.07 acres and encompassing Building A of approximately 110,000- square feet), and Lot 2, Block 1 (approximately 7.19 acres and encompassing Building B of approximately 120,000-square feet). Ms. McIntosh explained although the buildings would be located on separate lots, their access points, truck court, and select site improvements would be would be shared. The proposed redevelopment would also require shared access agreements with the adjacent Shingle Creek Crossing, given that their proposed off access off 55th Avenue North and along the frontage road running parallel to Highway 100 runs through the Shingle Creek Crossing development. Ms. McIntosh noted City Staff conducted a review of the submitted preliminary and final plat against City Code requirements, and specifically Section 15 (Platting) of the City Code of Ordinances and indicated that a 10-foot drainage and utility easement would need dedication on the plat around the entire perimeter of the Subject Property. All proposed utilities and stormwater management facilities will need to be constructed within this easement and an additional utility easement would need to be dedicated on the plat for any private water main and sanitary lines to account for future maintenance access and per the Utility Facilities Easement Agreement, which will also be required as a condition of approval. Ms. McIntosh stated as noted in the redlines provided by City Staff, the Applicant will need to revise the submitted final plat to account for missing drainage and utility easements, missing square footage totals for each proposed lot, as required under Section 15-105.B.b.1, and address minor comments regarding the locations of certain symbology and bearings. Ms. McIntosh added a comprehensive plan amendment is required anytime a community changes any part of a municipality’s adopted comprehensive plan, including, but not limited to changes resulting from neighborhood or small area planning activities, land use changes to allow a proposed development, proposed forecast changes to proposed MUSA (Metropolitan Urban Service Area) changes in service or staging, text changes to revise a policy or land use category, routine updates to incorporate new information or update a public facilities agreement. These requests are ultimately submitted to the Metropolitan Council for review and final approval; however, they require a recommendation from the local planning body, and local governing body PC Minutes 6-23-22 -4- DRAFT authorization for the amendment. In certain cases, an adjacent jurisdictional review is also required to allow for other affected municipalities and districts to weigh in on any potential impacts. Ms. McIntosh stated the property currently has a future land use designation of Transit- Oriented Development (TOD), which allows for a range of 31.01 to 130 dwelling units per acre, and is a new land use designation under the 2040 Comprehensive Plan. The request is to re-designate the Subject Property to Business Mixed-Use (B-MU), which is also a new land use designation that guides for a mix of business, light industrial, and supporting retail or service uses, and is intended to create a more dynamic and connected experience for potential workers in these areas. Ms. McIntosh pointed out during the undertaking of the 2040 Comprehensive Plan, the Subject Property was still in operation as a Sears department store and auto center. The aforementioned businesses closed well into the updating of the City’s Comprehensive Plan and given that the properties had continuously operated since 1962, ownership had provided no clear direction as to their potential re-use, and a market study had not yet been completed, the City guided the Subject Property to TOD given its proximity to a Bus Rapid Transit stop, and its ability to offer a broad mix of land use options, with a minimum of 75-percent of this designation slated for high- density residential use, and the remaining 25-percent slated for supporting retail, office, and commercial uses. Although the Subject Property was in transition during this process, the 2040 Comprehensive Plan denotes the Subject Property as a “potential area of change.” Ms. McIntosh stated the 2040 Comprehensive Plan recognized that not all of the properties guided under the TOD designation would be appropriate housing sites, and indicated that other areas, such as the City’s Opportunity Site, would likely take the bulk of housing needs; whereas other sites located around Xerxes and Brooklyn Boulevard would be more accommodating and capable of providing commercial uses and a jobs base. Ms. McIntosh noted it is hoped that a re-designation to B-MU would address the 2040 Comprehensive Plan’s goal of creating a vibrant business center via the creation of experience and by promoting and encouraging businesses, commercial users, retailers, and in some cases, households, to plan for interconnected systems that result in a more active and vibrant center. Given that the adjacent Shingle Creek Crossing development has yet to fully build-out, it is also hoped that the draw of additional jobs and activity to the Subject Property would create the additional energy and traffic needed to develop the remaining Shingle Creek Crossing Lots. Ms. McIntosh explained overlay districts generally apply an extra level of regulations or development criteria above the standard underlying zoning district. The Central Commerce Overlay District is an area roughly bounded by I-694 on the north, Highway 100 on the south and east, Brooklyn Boulevard on the west, and Shingle Creek on the north, and includes a specific list of permitted and prohibited uses. Ms. McIntosh noted in July 2018, and with the closure of the Sears Department Store imminent, City Council adopted an interim ordinance to authorize a study and place a moratorium on the Subject Property, as it was the last remaining remnant of the former Brookdale Mall and had been PC Minutes 6-23-22 -5- DRAFT excluded from the master planning activities that took place as part of the Shingle Creek Crossing redevelopment. It was during this moratorium that City Staff reviewed the existing Zoning Code and suggested several amendments to the Central Commerce Overlay District to remove the least desirable uses from being permitted within the Central Commerce Overlay District. A work session was held by City Council in July 2019 to further address a potential land use study of the Subject Property and moratorium, and in August 2019, City Staff brought forth amended language that clarified permitted and prohibited uses under Section 35-2240 (CC Central Commerce Overlay District), which were subsequently approved by City Council. Ms. McIntosh stated the Applicant is requesting an amendment to the Zoning Code and associated map to remove the Subject Property from the Central Commerce Overlay District, and whose uses are outlined in Section 35-2240 (CC Central Commerce Overlay District), as the proposed usage is not explicitly outlined as either a permitted or prohibited use. As the development proposal is speculative in nature, City Staff has worked with the applicant to put parameters on the flexibilities that would be granted under this proposal, specifically, that limits be placed on the industrial/ warehouse usage of the property, and that no outdoor storage be permitted. Ms. McIntosh noted City Staff feels that these requests are in keeping with the intent of the amendments approved in 2019 by City Council, which placed additional prohibitions on auto repair establishment, gas stations, truck and trailer rental establishments, and indoor storage establishments. The Central Commerce Overlay District has long held prohibitions on standalone sauna and massage establishments, currency exchanges, pawn shops, and secondhand goods dealers. As part of the ongoing Zoning Code update, the Central Commerce Overlay District is slated for removal; however, as that work is not yet complete, the submitted proposal requests the removal of this property from the Overlay District. In 2019, a similar request was made and approved by City Council as part of the redevelopment of the former Jerry’ s Foods site (5801 and 5803 Xerxes Avenue North) into a combined 270-units of housing across two multi- family residential buildings, now known as Sonder House and Sonder Pointe, and approval of the Crest Apartments expansion in 2021 (6221 Shingle Creek Parkway) required removal from the Overlay District as well. Ms. McIntosh stated Planned Unit Developments (PUD) allow for flexibility in the Zoning Code for developments that would not be allowed under existing regulations. PUDs are often used to achieve higher quality development or achieve other City goals in exchange for zoning flexibility under City Code. Given that the major update to the City Zoning Code is currently underway and changes to districts are anticipated in order to align with the 2040 Comprehensive Plan, the request would be to re-zone following guidance from the 2040 Comprehensive Plan future land use designations for the Subject Property. This allows for flexibility within the Zoning Code for developments which are either not defined or outlined as a use under the existing regulations. PUDs are often used to achieve a higher quality development, or achieve other City goals, in exchange for zoning flexibility from the City Code. PC Minutes 6-23-22 -6- DRAFT Ms. McIntosh explained PUDs may only contain uses consistent with the City’ s Comprehensive Plan and the uniqueness of each PUD requires that specifications and standards for streets, utilities, public facilities, and the approval of a land subdivision may be subject to modifications from the City ordinances generally governing them. Essentially, the City Council may approve plans that are not in compliance with the usual specifications or ordinance requirements where it is found that such are not required in the interests of residents or the City, although plans shall comply with all watershed, state, and federal storm water, erosion control, and wetlands requirements. Ms. McIntosh stated as proposed, the request would be to re-zone from PUD/C-2 (Planned Unit Development/Commerce) District to a new PUD with an underlying Business Mixed-Use designation (PUD/ MX-B). Official Zoning Map records indicate that the Subject Property was zoned B-2 (Regional Business District) in 1961, but later zoning map records indicate that the property was designated as a C-2 (Commerce) District property by 1972. Ms. McIntosh noted in 1999, the City approved the establishment of a Planned Unit Development (PUD), which comprehended, “new site and building plan approvals for the expansion, redevelopment, and rejuvenation of the Brookdale Regional Shopping Center,” and certain variations to allow for reduced green strips, non-major thoroughfare setbacks, parking dimensional standards, parking ratios, and increases in allowable restaurant use and freestanding signage. Ms. McIntosh added in 2011, the City approved City Council Resolution No. 2011-128 (Exhibit D), which approved an amendment to the 1999 Brookdale Regional Shopping Center Mall PUD redevelopment plans the Subject Property had been subject to, and in response to recent City approvals for the Shingle Creek Crossing Planned Unit Development, as approved under City Council Resolution No. 2011-85. The aforementioned amendment in 2011 allowed for certain parking ratio reductions, a reduction in the drive aisle parking widths, and a zero-lot line setback along certain portions of the Subject Property. Ms. McIntosh pointed out the plans submitted and as contemplated under Planning Commission Application No. 2022- 004 would require certain flexibilities to account for the speculative nature of the two proposed business park type buildings. The current Zoning Code does not contemplate speculative uses; therefore, establishment of a Planned Unit Development is requested to provide parameters in granting these flexibilities. Similar examples of light industrial type developments in Brooklyn Center include the PUDs established to allow for the redevelopment of lands off France Avenue North and Highway 100 (i.e. 4001 Lakebreeze Avenue North), and a PUD established in 1995 for a speculative business park development constructed in the 1980s off Parkway Circle and Shingle Creek Parkway (e.g. 6601 Shingle Creek Parkway), which required certain common parking allocations between buildings and access. Ms. McIntosh stated the City has requested that a minimum of 20-percent finished space be accommodated within the development, with the remaining (maximum) 80-percent for industrial- warehouse use. The Applicant indicated an openness in maintaining this split of use; however, requested that the 20-percent use be set for “non-warehouse uses.” The Applicant indicated that the language noted below was used during the approval process for another project in Arden Hills PC Minutes 6-23-22 -7- DRAFT to define “non warehouse uses” and proposes to utilize the same language for this request. Warehousing and wholesaling shall not exceed 80 percent of the total floor area. The remaining 20 percent of the total floor area shall be non-warehouse uses such as a combination of uses including, but not limited to, office, manufacturing, production, research and development, lab and/ or showroom.” Ms. McIntosh showed a table with proposed setbacks for the site. As proposed, primary site access would be gained from an existing drive off 55th Avenue North and Xerxes Avenue North on the west, with connections to the surrounding access drives shared with adjacent Shingle Creek Crossing properties. The truck route would be accessible inbound from the north and south entrance points within Shingle Creek Crossing; however, trucks would need to exit the Subject Property via the south access road, which continues up towards Shingle Creek Parkway and Bass Lake Road (County Road 10). This is the same access road utilized by trucks making deliveries to the adjacent Walmart (1200 Shingle Creek Parkway). Ms. McIntosh explained primary truck access would be gained along the south portion of the Subject Property utilizing an extension of the access road running parallel to Highway 100 and up to Shingle Creek Parkway and Bass Lake Road (County Road 10). The Applicant indicates that while the western drive would be maintained, signage would be installed, and the drive aisles narrow so as to minimize the likelihood of truck drivers traversing through the western drive aisle towards Xerxes Avenue North (Building A). Ms. McIntosh noted the main access entry off Xerxes Avenue North (55th Avenue North) was modified to provide one in-bound lane, which would enter a “ T” intersection internal to the Subject Property. The Applicant has indicated that they have been in communication with the Shingle Creek Crossing property owner (Gatlin Development Company) regarding their proposed easement parking lot of 18 spaces, access, and site improvements. Ms. McIntosh stated City Staff requests that as part of any approvals, the Applicant submit detailed vehicle turning and tracking movement diagrams for delivery vehicles and garbage trucks to demonstrate specific and actual routes. It is also requested that truck traffic be concentrated along the south access road when possible and directional signage provided so as to minimize truck traffic along the north and west drives, and particularly as the drive aisle widths and turns do not appear conducive to truck traffic. Ms. McIntosh added City Staff has also set an expectation that conflicts between pedestrians and vehicular traffic along the north drive be minimized through utilization of this south access road. As the project engineer (Kimley-Horn) has also designed and maintained the Planned Unit Development master plans for the adjacent Shingle Creek Crossing, it was noted that the proposed truck access routing would maintain consistency with the Shingle Creek Crossing (SCC) Delivery Circulation Exhibit provided in the master plan set. Ms. McIntosh noted the Applicant submitted a full civil plan set, including site plans and a traffic generation memo, prepared by Kimley-Horn, and last revised June 9, 2022. Per City Staff request, PC Minutes 6-23-22 -8- DRAFT the original traffic generation memo provided, which solely reflected an industrial use, was revised to reflect 80-percent industrial and 20-percent office use. City Staff reviewed the aforementioned memo and deemed it acceptable; however, the Applicant will need to meet any and all requirements as outlined in the reviews conducted by the Minnesota Department of Transportation and Hennepin County. Ms. McIntosh stated Hennepin County provided feedback to City Staff following reviews with their plat review committee representatives from traffic operations and bicycle and pedestrian planning. They anticipate minimal impacts to Brooklyn Boulevard (CSAH 152), despite additional morning peak hour trips, as the change in use from department store and automobile parts and service center to industrial and office would create an overall reduction in trips. Ms. McIntosh stated MnDOT initially prepared a memo in March 2022 and requested that a Traffic Impact Study be completed to accurately evaluate impacts to the trunk highway system. City Staff reviewed the submitted overall site plan, identified as Sheet C300, with the assumption of 80- percent industrial and 20-percent non-warehouse use (i.e. “office” for the purposes of calculating minimum parking). Similar stipulations were placed on approval of Planning Commission Application No. 2021-006, which was approved for the redevelopment of a former bowling alley located at 6440 James Circle North for an approximately 64,000-square foot business-flex building adjacent to existing hotels, office, and restaurants, and also located in a proposed area of redevelopment under the 2040 Comprehensive Plan. Ms. McIntosh explained assuming this, a minimum of 368 parking spaces would be required on the Subject Property. As proposed, the Applicant has provided 357 parking spaces, with an additional 18 parking spaces proposed as part of an easement that would be located on the Shingle Creek Crossing development. The Applicant would need to work with the adjacent property owner (Gatlin Development Company) to obtain any necessary parking and access easements. The Applicant has indicated that the parking counts presented are consistent with those typically provided for a similar development of this size. Ms. McIntosh stated in reviewing the proposed loading berths and truck court, the submitted plans comply with the minimum berth requirements as outlined in Section 35-600 (Off Street Loading), as a minimum of 4 berths would be required for buildings ranging between 100,000 and 250,000- square feet. The berths would be located more than the minimum 25 feet from any right-of-way intersections, and would be located outside of any required yards. Dimension-wise, the first berth required shall not be less than 12 feet in width and 50 feet in length, with additional berths providing at least 12 feet in width and 25 feet in length. A minimum height of 14 feet is also required. As proposed, the submitted site plans reflect a 60-foot berth depth along each of the respective buildings and an 80-foot wide shared drive aisle for the truck court. Ms. McIntosh stated in terms of alternative transportation options, the Subject Property is directly adjacent to bus stops along Xerxes Avenue North that provide BRT service. MnDOT recommended that the Applicant contact Metro Transit to evaluate potential impacts to service given the proximity of existing bus stops, and potential mitigative strategies pending approval of the PC Minutes 6-23-22 -9- DRAFT proposal. As part of City Staff review, requests were made to provide additional sidewalk connections along the north end of the Subject Property and to Shingle Creek Crossing, with additional requests to extend certain sidewalk segments and relocate the proposed midblock pedestrian crossing, as it is located on a curve. Ms. McIntosh noted the Applicant also intends to complete an existing trail gap as part of the proposal, which would provide continued routing for those utilizing Three Rivers Park District’ s Twin Lakes and Shingle Creek Regional Trails, as well as a pedestrian bridge that crosses Highway 100 to the neighborhoods adjacent to Centerbrook Golf Course and Lions Park. The Shingle Creek Crossing Development has an existing 18-foot trail easement with 10-foot trail running along Highway 100, and the Applicant has proposed a continuation of this section. Per City Staff request the applicant shall provide a trail plan and profile as part of any final development plans. Per MnDOT comments, an existing barrier blocking the trail segment near HOM Furniture should be removed pending approval of the proposal. Ms. McIntosh noted City Staff provided commentary to the Applicant in March and May 2022 with regard to preferred access for semi-truck traffic utilizing the proposed loading bays and truck court, and the Applicant revised the plan sets based on City Staff comments. As proposed, access to the loading bays would be provided via the north drive off 55th Avenue North and utilizing an extension to an existing access road running along the southern portion of the Subject Property, parallel to Highway 100. City Staff worked with the Applicant through multiple plan iterations to clean up the access and potential internal points of vehicle and pedestrian conflicts off 55th Avenue North and the roadway extension between 55th Avenue North and the Shingle Creek Crossing development. Although a north and west access is maintained off the proposed truck court, the Applicant has indicated installation of “No Trucks” signage on the submitted plans so as to route exiting trucks to the south. Ms. McIntosh stated as proposed, the submitted site plans indicate 24-foot wide drive aisles throughout the north parking lots, which is the minimum width required to allow for two-way traffic. The parking area just south and west of Building A (110,000-square feet) indicates a tapering of drive aisle widths from 27 feet down to 25 feet, while the drive aisle just south of Building B (120,000-square feet) is noted at 30-feet in width to accommodate truck traffic, and widths of 25 feet along the eastern edge of the building, which orients towards the west side of Walmart. The submitted site plan also indicates typical 18-foot parking space depths and 9-foot widths, which satisfy the City’ s minimum parking dimension requirements as outlined within the Zoning Code. Ms. McIntosh added the current Zoning Code notes that, “all exterior lighting shall be provided with lenses, reflectors, or shades, so as to concentrate illumination of the property of the owner or operator of said illumination devices.” A photometric plan was submitted with a fixture specification schedule; however, no minimum, maximum, or average foot candle provisions are provided. City Staff also requests the photometric plan be revised to more clearly indicate the property lines, as the Zoning Code specifies that lighting shall not exceed three-foot candles measured at property lines abutting residentially zoned property, or 10-foot candles measured at PC Minutes 6-23-22 -10- DRAFT the property lines abutting the street right-of-way or non-residentially zoned properties. As is specified, no glare shall emanate from or be visible beyond the boundaries of the illuminated premises. Ms. McIntosh stated the photometric plan indicates the fixtures are generally consistent with the current Zoning Code requirements. Although it appears existing lighting will be maintained between the northerly drive running between the Subject Property and adjacent Shingle Creek Crossing development, City Staff requests that the Applicant work with the Property Owner of Shingle Creek Crossing to ensure the lighting and landscaping is consistent along this segment of transition. Ms. McIntosh explained as the submittal is speculative in nature, no communal trash facilities were depicted on the submitted plan sets. The Applicant did provide detailing within the submitted landscape plans for a trash receptacle to be located at the southwest corner of Building A (110,000 square feet) and in proximity to proposed tables and benches. Pending approval of the submittal, the Applicant shall provide details on the intended location for trash facilities, and detail sheets with revised site plans for any exterior trash enclosures. Ms. McIntosh stated all ground mounted equipment shall be effectively screened from adjacent public rights-of-way and properties by a solid wall or fence constructed of wood, masonry, or other durable materials that are complementary to the materials used on the primary building. Roof mounted equipment shall also be screened from view through use of parapets, wall/ fencing materials, or paint to match surrounding colors when visible from the public right-of-way. Ms. McIntosh added as proposed, the Applicant intends to screen the shared truck court from view of Highway 100 with a berm and landscaping and in strategic locations along the north end of the Subject Property, and facing the western edge of Shingle Creek Crossing. Although a fence and retaining wall are indicated on the submitted plan sets as proposed, no detailing is provided. The Applicant shall work with City Staff as necessary to determine requirements for placement and permitting. Ms. McIntosh explained the City’s Architectural Design Guidelines require at least 50-percent of each elevation of a building to be constructed of Class I materials, with the remainder constructed of Class II materials. An elevation by elevation breakdown of Class I and Class II building materials was provided by the Applicant per City Staff request. Ms. McIntosh noted as proposed, both buildings would be designed with similar materials comprised of pre-cast concrete panels textured with stucco texture, a wood-look fiber cement, and aluminum composite material panels. As proposed, the majority composition of each building elevation is glass and pre-cast concrete, which are considered to be Class I building materials under the City’ s Architectural Guidelines; therefore, the minimum thresholds are met. Nichiha, which is indicated as a Class II material on the submitted architectural plans, has been determined in past projects to be a Class I type building material. PC Minutes 6-23-22 -11 - DRAFT Ms. McIntosh explained City Staff provided feedback to the Applicant in March and May 2022, and it was requested that the Applicant provide enhanced architectural façade treatments along Highway 100, Building A’s northwest corner, Building B’s northeast corner, and overall increased articulation and glazing for visual interest. City Staff indicated that while the requests would ultimately re-zone the Subject Property to accommodate the use, the Applicant should think creatively for ways to complement the adjacent retail use. Ms. McIntosh pointed out City Staff has worked with the Applicant on a few iterations of the site plan and indicated early on that the Applicant should maintain the building line currently in existence today with Buildings 1 through 5 of the Shingle Creek Crossing development. Through discussions with the Applicant it was determined that it would be infeasible to bring the building up to the same exact build line due to impacts to the overall provided square footage of each building, and site constraints to parking and drive aisles given the north-south orientation of the proposed buildings. Ms. McIntosh added as part of this submittal, the Applicant indicated revisions to the architectural plans to provide an expanded entry features on the north and south elevations, and the addition of reveals and adjustments to the glass pattern between entrances along the front of the building. The applicant has indicated that the proposed buildings would have clear heights of 28-feet to attract businesses in need of modern, Class A space. The overall height of the proposed buildings from ground level to the top-most parapet is proposed at just under 35.5 feet. This height is similar to the adjacent Walmart, whose ground level to parapet heights are at approximately 31.5 feet. Ms. McIntosh stated the project submittal includes a landscape plan and planting schedule. Although City Code does not have any specific requirements on the species of landscaping, the City has operated under and held new and redeveloped areas to complying with the City’ s adopted Landscape Point System policy, which assigns points to a given site based on the acreage and type of development. In discussions with the Applicant, and in consideration of the draft landscaping requirements outlined within the City’s draft Unified Development Ordinance (UDO), City Staff requested that the Applicant explore opportunities to diversify the landscaping and provide native and resilient plant types when possible. Ms. McIntosh explained the Landscape Point System outlines requirements for uses such as “light industrial,” “heavy industrial,” and “office/ industrial,” and requires a specific amount or number of landscaping units based on the maximum percentage of certain. As the Applicant is requesting PUD and re-zoning approvals, an amendment to re-designate the Subject Property under the 2040 Comprehensive Plan, and provided the Subject Property’s adjacency to a retail shopping center, City Staff calculated the landscaping assuming the “Office/ Industrial” use. It should be noted that the Overall Landscaping Plan clearly indicates an assumption of “Light Industrial,” which has lesser requirements for landscaping. Assuming an approximately 15-acre site, the Subject Property would have to accrue 990 points. Ms. McIntosh noted based on a review of the submitted Landscape Plan, dated May 24, 2022, the plan is deficient by 75 points. The Applicant could easily fulfill this gap by providing any PC Minutes 6-23-22 -12- DRAFT combination of the above planting types, as none of the maximum points have yet been met. The Applicant will need to ensure all plantings meet minimum sizing requirements, as outlined above in Table 3. As part of any construction set submittals, a copy of an irrigation plan drawing will be required for review and approval, and an irrigation system maintained on-site. Ms. McIntosh stated per City Staff comments addressed in the memorandum provided by the City Engineer Mike Albers, dated June 17, 2022, and the supplemental redlined civil set, the Applicant should ensure adequate Clearview Triangles are provided at all street intersections per City Code Section 25-802, and the Applicant should verify the placement of trees and other landscaping within proximity to proposed utilities. The Applicant should consider stepping certain landscaping back at and near intersections and pedestrian crossings to provide adequate visibility for both motorists and pedestrians. Ms. McIntosh pointed out no specific signage requests were made regarding new or revised signage for the Subject Property, and as the proposal is speculative in nature, none were anticipated at time of submittal. The City is currently underway with an update to multiple City codes, including the Sign Code. Any signage will need to comply with the allowances as outlined in the adopted City signage regulations at time of submittal, and the Applicant will need to apply for and receive issuance of a sign permit prior to any installation. Ms. McIntosh explained Mike Albers, City Engineer, reviewed the plans and provided a memorandum, dated June 17, 2022. Most of the comments pertain to the need for plan corrections and additional details relating to stormwater, sanitary sewer, watermains and hydrants, roads, trails, and sidewalks, and traffic. An MPCA NPDES permit is required as the total disturbed area would exceed one acre, and a Construction Management Plan and Agreement, and Utility Facilities Easement Agreement shall be submitted to the City in advance of any permit release. The Applicant will also require a watershed plan review and conform to watershed rules. It should be noted that the Watershed Commission project review is currently underway. Ms. McIntosh added a stormwater report, completed by Kimley-Horn, dated February 11, 2022, and revised May 24, 2022, and a copy of the traffic memo, last revised June 9, 2022, were provided as part of the submittal. Ms. McIntosh noted Building Official Dan Grinsteinner conducted a cursory review of the submitted plan sets and provided a memorandum dated June 21, 2022. Pending approval of the requests, the Applicant will need to submit full construction plans, including but not limited to: architectural, structural, mechanical, plumbing, electrical, civil, landscaping, and photometric plans to the City for review. A fire sprinkler and monitoring system is required for installation and is to be maintained at all times, and sufficient fire hydrants shall be provided. Ms. McIntosh stated the Applicant will also need to meet any minimum ADA requirements with regard to the building and site improvements, and prior to issuance of any building permits, a SAC determination shall be submitted to the Metropolitan Council and any associated fees shall be paid at time of permit issuance. All building plans are subject to review and approval by the Building PC Minutes 6-23-22 -13- DRAFT Official with respect to applicable codes prior to the issuance of permits. City Staff requests that as part of any construction set review, a CPTED (Crime Prevention through Environmental Design) review be completed by City Staff. Ms. McIntosh added the submitted plan sets were forwarded on to contacts at Hennepin County, the Minnesota Department of Transportation (MnDOT), and the Watershed Commission review. Any approval of Planning Commission Application No. 2022-004 is subject to the Applicant complying with any requested revisions or recommendations as outlined by the aforementioned authorities. Ms. McIntosh offered to answer any questions. Commissioner Dunn asked if there will be other establishments that will go into the new building. Ms. McIntosh explained the uses are outlined in the resolution. There are proportions of designated uses. Ms. McIntosh read from the resolution an exact definition of the use options. No more than 80- percent could be industrial use. The remaining 20 percent could be for a number of uses included an office use. Commissioner Dunn explained he would like to see an option for a commercial kitchen use for food trucks to access. Commissioner Guannu asked how many other developments in other cities have been so close to a shopping center. Vice Chair Omari suggested they open the floor to public comment before more questions are asked. OPEN TO PUBLIC COMMENTS – APPLICATION NO. 2022-004 There was a motion by Commissioner Jones, seconded by Commissioner Dunn to open the public hearing on Application No. 2022-004. Voting on the motion Vice Chair Omari, Commissioners Dunn, Guannu, and Jones voted aye. The motion passed unanimously. No one appeared to address the Planning Commission. MOTION TO CLOSE PUBLIC COMMENTS (HEARING) There was a motion by Vice Chair Omari, seconded by Commissioner Jones, to close the public hearing on Application No. 2022-004. Voting on the motion: Vice Chair Omari, Commissioners Dunn, Guannu, and Jones voted aye. The motion passed unanimously. Dan Salzer, representative of Scannell Properties, stated there are some areas in the Twin Cities with similar developments such as the area with the Plymouth movie theater and store which is surrounded by a business park. They worked to ensure pedestrian connectivity, such as with the PC Minutes 6-23-22 -14- DRAFT trailway. Scannell Properties has done about six million square feet of product in the market and has included a variety of different thing such as distribution facilities, medical manufacturing, or a gymnastics company. The project is a great opportunity to grow businesses in Brooklyn Center. Vice Chair Omari asked how the space may compete with or work with the Opportunity Site which is nearby. Ms. McIntosh stated the proposals for the first phase of the Opportunity Site include multi-family buildings, an event center, a daycare, and barber, and wellness suites for therapy. There is a proposed entrepreneurial market, but there aren’t any planned industrial uses. Mr. Salzer added it would be a great opportunity to live, work, and play in one area. Commissioner Guannu asked if there are any planned tenants for the project. Ms. McIntosh explained the site used to be a retail store and auto business. The proposal would include demolition of the existing buildings and new buildings would be put up. There is speculation for light-industrial or business park users. Vice Chair Omari noted the Planning Commission has talked about sound and traffic concerns for previous developments. Therefore, they are unsure of how specific they need to be with questions for the applicant. Ms. McIntosh stated the 694 Business Center proposal for the former bowling alley was a speculative project. In Shingle Creek Crossing, they didn’t have identified tenants for most of the space. Commissioner Jones asked what the overlay district would prohibit. Ms. McIntosh stated the overlay district was put in place for Brookdale Mall to keep away less desired or seedier uses. The intent is to take the uses and incorporate them in without need for an overlay district. Commissioner Jones asked if removal of the overall district would allow for those businesses. Ms. McIntosh stated they would have to pull the draft. There was discussion for certain types of uses to be assigned to a zoning district as opposed to a whole overlay district. Something might be permitted in a mixed-use district versus a blanket approach of an overlay district. Ms. McIntosh discussed the nuances between PUDs, zoning districts, and overlay districts. Commissioner Jones asked to consider certain precautions to avoid some of the less desirable uses outlined in the current overlay district. Ms. McIntosh stated they would establish a PUD, but the underlying use would be a business mixed-use, which will be a new zoning district in response to the 2040 Comprehensive Plan. She showed a table of different permitted uses for different zoning districts. Commissioner Dunn noted the buildings on Bass Lake Road are mixed uses all the way up to Brooklyn Boulevard. Ms. McIntosh stated those buildings are for the most part, designated C-1 or C-2 districts currently. She noted the City Attorney is reviewing the draft provisions of the Zoning Code update. The PUD would specify requirements for no outdoor storage and the percentage breakdown of agreed upon uses. PC Minutes 6-23-22 -15- DRAFT Commissioner Jones asked if completion of the trail is required. Ms. McIntosh confirmed the trailway completion would be required because it is part of the site plan. Also, there is language that requires trails in accordance with those of the Shingle Creek Crossing development. Vice Chair Omari asked which trail they are talking about. Ms. McIntosh stated there is a trail that runs behind Walmart. Mr. Salzer stated the trail currently stops at the Sears site. Ms. McIntosh stated there is currently a barrier that would be eliminated. Most people would have to go up Xerxes to Bass Lake Road. There was a comment from MnDOT to remove the barriers as well. The segment is also addressed in the 2040 Comprehensive Plan. Commissioner Guannu noted there are a lot of pedestrians in the area, so polluting the site with semi-trucks would not be a good look. Ms. McIntosh stated there is a memo that outlines what the intensity of traffic generation was when Sears was in business. The new use would be about half of the traffic, though there would be more semi-trucks. The Applicant will have to answer to MnDOT or other agencies for a traffic impact study. Mr. Salzer added one of the conditions of approval for the mix of uses would impact the traffic. On average, the finish level is 10 to 12 percent, and the 20 percent requirement would force the developer to attract users that have lower truck volumes. The medical manufacturing companies typically have about two trucks per day, but the trucks still need access. The truck routing will promote traffic to use the south access point. Currently, trucks can come in or out at the south access point, and the north access point is only for trucks to enter. Commissioner Guannu asked if the project has been before the public when it was originally presented to the Council. Mr. Salzer stated they did a concept plan review with the Council, but it did not include a public hearing. There were questions about retail, so they commissioned a study for the highest and best use of the site. Transformco tried to find retail users, but could not, and noted that some of the outlots at Shingle Creek Crossing are intended for retail and restaurants and aren’t completed yet. It was determined that a business use to bring employment opportunities to the City in proximity to retail spaces was the best. Commissioner Guannu asked if community members came forward. Mr. Salzer explained they presented to the Council twice, and there was a community engagement session with a few residents who participated virtually. There was a lot of discussion about the uses, the pedestrian accessibility, and the external look from the meetings with the Council. They have redone the articulation and added windows in alignment with comments from the City Council. Ms. McIntosh noted they don’t always require concept review, but City staff will sometimes suggest for certain project proposals or in addressing particular City goals and strategies. Commissioner Guannu asked about the studies conducted that showed retail use would be difficult, and was there contemplation for other uses such as restaurants. Mr. Salzer stated the study looked at all retail types. They also looked at multi-family partners, but there wasn’t interest there. Ms. McIntosh noted that restaurant users are often regarded as the one of the highest risk type use with PC Minutes 6-23-22 -16- DRAFT a high fail rate. She further noted that there are other industrial-flex type uses such as the Caribou headquarters that has a retail store, and Northern Stacks in Fridley. Ms. McIntosh added Shingle Creek Crossing has restrictions in place that are above and beyond the what the City requires. For example, some users have agreements in place that do not allow certain types of uses, or minimum distancing requirements within the development. Vice Chair Omari stated the property has been sitting there for a very long time. He noted there may be a way they can encourage the businesses employ residents. ACTION TO RECOMMEND APPROVAL OF PLANNING COMMISSION APPLICATION NO. 2022-004 SUBMITTED BY SCANNELL PROPERTIES There was a motion by Commissioner Jones, seconded by Commissioner Dunn to recommend City to approve Planning Commission Resolution 2022-002 recommending that the City Council approve (1) preliminary and final plat for the NORTH 100 BUSINESS PARK ADDITION, (2) the submitted site and building plan, (3) re-zoning and establishment of a Planned Unit Development, (4) an amendment to the Zoning Code and associated Map to remove the Subject Property located at 1297 Shingle Creek Crossing from the Central Commerce Overlay District, and (5) an amendment to the City’ s 2040 Comprehensive Plan to allow for a re-designation of the Subject Property from Transit- Oriented Development (TOD) to Business Mixed-Use (B-MU), based on the submitted plans and findings of fact, as amended by the Conditions of Approval in the June 23, 2022 Planning Commission Report, and subject. Voting on the motion Vice Chair Omari, Commissioners Dunn and Jones voted aye. The motion passed. And the following voted against the same: Commissioner Guannu. The motion passed 3-1. 7. DISCUSSION ITEMS 7a. Return to In-Person Meetings and Upcoming Planning Commission Meetings Ms. McIntosh stated the meetings are back to in-person, but City staff is trying to host hybrid meetings. However, Planning Commissioners must be present in-person to vote. There is one open seat open currently on the Planning Commission, and it has been open for quite some time. There must be four members present in order to meet quorum and legally call a meeting to order, but that has been hard in recent months. Ms. McIntosh explained she has not had to bypass the Planning Commission in her time as a planner. She stated they had to notice the last application four times—while some of the noticing was due to the change in forum from virtual to in-person, the additional noticing was due to failure PC Minutes 6-23-22 -17- DRAFT to meet quorum. The Planning Commission, unlike others, has greater requirements and heightened levels of responsibility, and addressed the issues that come with delaying project requests. Ms. McIntosh noted she has tried multiple methods to times that work for the most people. She outlined what goes on behind the scenes once a Planning Commission application is submitted, including the notices of completion, public noticing, and state statute requirements requirements for review periods. The developers who want to build in Brooklyn Center and other applicants also require direction and answers to their questions and timelines. The next meeting is vital because it is the Opportunity Site and has a lot of eyes on it. Currently, Commissioner Dunn and Vice Chair Omari cannot make it. This means that the remaining four Commissioners must be present or a new public hearing notice will need to submitted for publication. Commissioner Guannu stated she would be available for the July meeting, but she will not be able to attend the August meeting. Ms. McIntosh noted a number of the members of the Planning Commission also appeared to be up for reappointment. Vice Chair Omari stated the public can attend virtually, but the Commissioners cannot. He stated he would be gone from July through September and possibly other meetings. Ms. McIntosh added they have been having to double notice in order to keep applications advancing and within the review periods, but that is an additional cost each time a public hearing notice is submitted. Commissioner Jones confirmed she would be available for the July meeting. Commissioner Dunn stated he cannot attend the July meeting. Ms. McIntosh stated there are tight timelines for various reviews and permits to be obtained, and especially before winter hits. Then there are additional costs incurred by builders if they have to build in the winter. Commissioner Jones inquired on the Opportunity Site project. Ms. McIntosh explained the Opportunity Site will include a large packet for review and provided a summary of the first phase. 8. ADJOURNMENT There was a motion by Commissioner Jones, seconded by Commissioner Guannu to adjourn the Planning Commission meeting. Voting on the motion: Vice Chair Omari, Commissioners Dunn, Guannu, and Jones voted aye. The motion passed unanimously. PC Minutes 6-23-22 -18- DRAFT The meeting adjourned at 9:06 p.m. _______________________________ __________________________________ Ginny McIntosh, Secretary Peter Omari, Vice Chair App. No. 2022-005 PC 08/11/2022 Page 1 Planning Commission Report Meeting Date: August 11, 2022 Application No. 2022-005 Applicant: Joslyn Manufacturing Company LLC Property IDs: 10-118-21-23-0007, 10-118-21-32-0058, and 10-118-21-32-0059 Request: Issuance of a Special Use Permit for a planned soil remediation project within the designated 100-year floodplain REQUESTED ACTION: Applicant Representative Barr Engineering Company, on behalf of Joslyn Manufacturing Company LLC (“the Applicant”) is requesting issuance of a Special Use Permit for a planned soil remediation project within the designated 100-year floodplain, and as part of continued clean-up efforts for the Joslyn Superfund site. The Subject Property, as contemplated under this application, is comprised of three un-addressed properties identified under the following Property IDs: 10-118-21-23-0007, 10-118-21-32-0058, and 10-118-21-32- 0059. The aforementioned properties are generally located to the south and west of the industrial property commonly known as 4837 Azelia Avenue North, and east of Middle Twin Lake. For clarification, the Subject Property is also referenced in Exhibit A as, “Operable Unit 5” or “OU5.” As part of the application process, a public hearing notice was submitted to the Brooklyn Center Sun Post for publication on July 28, 2022 (Exhibit B), and notices were mailed to property owners within vicinity of the Subject Property. COMPREHENSIVE PLAN AND ZONING STANDARDS Map 1. Subject Property Location. • Application Filed: 07/11/2022 • Review Period (60-day) Deadline: 09/09/2022 • Extension Declared: N/A • Extended Review Period Deadline: N/A App. No. 2022-005 PC 08/11/2022 Page 2 Site Data: 2040 Land Use Plan: Industrial/Utility, High Density Residential (15.01-31 DU/acre) Neighborhood: Twin Lake Current Zoning: I2 (General Industry) District, R4 (Multiple Family Residence) District Site Area: Approximately 11.7 Acres Surrounding Area: Direction 2040 Land Use Plan Zoning Existing Land Use North RR ROW N/A Undeveloped (Railroad ROW) South High Density Residential (15.01-31 DU/Acre) R4 (Multiple Family Residence) District Single Family Detached, Two or Three Family, Townhome, and Apartments East Industrial/Utility | High Density Residential (15.01/31 DU/Acre) I2 (General Industry) District and R4 (Multiple Family Residence) District Undeveloped, Industrial/Utility, and Single Family Detached West (Water)| High Density Residential (15.01-31 DU/Acre) I2 (General Industry) Open Water (Middle Twin Lake) EXISTING CONDITIONS Image 1. Subject Property Existing Conditions. App. No. 2022-005 PC 08/11/2022 Page 3 The Subject Property is currently undeveloped, heavily wooded, and access is restricted due to the installation of a chain link fence and warning signage. Said fence was installed to limit the risk of exposure to dioxins that are present in high concentrations within the soil to this day and are extremely toxic through ingestion (e.g. consuming animals exposed to dioxins) or by touching contaminated soils. Refer to Image 1 above. BACKGROUND Image 2. General Area of Consideration for Issuance of Special Use Permit | 1945 Imagery of Joslyn Site (Credit: MHAPO). Image 3. Joslyn Site Cleanup Area with Subject Property Noted in Yellow (Credit: Minnesota Pollution Control Agency). Joslyn Site App. No. 2022-005 PC 08/11/2022 Page 4 From the 1920s until around 1980, what is known as “the Joslyn Site” (refer to Images 2 and 3 above) was used for wood-treating operations, which led to the contamination of soil, sediment, and groundwater with pentachlorophenol (PCP) and polynuclear aromatic hydrocarbons (PAHs). Evidence of this contamination was observed as early as 1961 in several residential wells near the Joslyn Site, and in 1980, the Minnesota Pollution Control Agency (MPCA) also observed evidence of PCP and phenols in nearby wells. Following several investigations by Joslyn Manufacturing Company (the Applicant) in the early 1980s, it became clear that the ground water and soils were indeed contaminated with compounds associated with the Joslyn Site operations, and namely the wood treating process. In 1983, the entirety of the Joslyn Site underwent an investigation and the MPCA issued a Request for Response Action (RFRA) to the Applicant in response to the Minnesota Environmental Response and Liability Act of 1983 (MERLA) to, “abate the release of hazardous substances at the Joslyn Site.” The overall site, including the Subject Property, was listed by the Environmental Protection Agency (EPA) on the federal National Properties List (NPL) in 1984 and the state Superfund list, referred to as the Permanent List of Properties (PLP), in 1985. After an investigation was completed, remedial actions were selected for the site, with distinct elements of the remedial actions being described using the term “Operable Unit” (OU). The Subject Property, as outlined under this application request, is referred to as “Operable Unit 5,” or “OU5.” A historical record of the investigations and remedial actions for the other Operable Units identified for the Joslyn Site are noted in the Applicant submittal and narrative (refer to Exhibit A). The largest parcel of the Subject Property (approximately 11.1 acres) is comprised of wetland and wooded uplands, with the majority of the area located within both the 100-year flood plain and the ordinary high- water level (OHWL) of Middle Twin Lake. This area was not used for significant operations associated with wood treatment; however, it became compromised by surface-water runoff from other areas where wood-treating operations occurred. The closest area to the Subject Property was primarily redeveloped to an industrial use in 1999 and is commonly known as 4837 Azelia Avenue North today. The two, smaller residential lots contemplated under this application are currently undeveloped. The lots are owned by the Applicant and are comprised of wetlands, trees, and shrubs. Approximately half of these parcels fall within the 100-year flood plain. These southern lots abut existing residential and multi-family residential properties off Twin Lake Avenue North. Various investigations completed on the Subject Property through 1999 indicated contamination above the recommended cleanup levels on the Subject Property (OU5). A fence was installed around the Subject Property to minimize trespassing and limit the overall potential for exposure to dioxins, which are present at high concentrations within the soil. The major risk comes through ingestion (e.g. consuming animals exposed to dioxins), and touching the contaminated soils. Federal law maintains an expectation that remedial action and treatment will be used to address “principal threats” present in Superfund sites when possible. Over the years, investigations determined the soils within the Subject Property contain “principal threat” waste and pose a potentially significant risk to human health or the environment via exposure, however it was determined that the mobility of the contaminants associated with the Subject Property soil is extremely low. MPCA completed the “West Area Feasibility Study” to evaluate the risk to human and environmental health and determined the best course of remedial work for the soil of the Subject Property. The Applicant is proposing remedial action which includes the excavation of shallow soils with contamination, which will be either consolidated on-site or transported to an off-site facility for disposal. App. No. 2022-005 PC 08/11/2022 Page 5 Any contaminated soils that remain on-site will be capped with fabric and below approximately two-feet of clean soil. This area would be seeded with grass and mowed regularly to prevent any large bushes or trees from growing on the mound and creating the potential for exposure to contaminated soils. In documentation submitted by the Applicant (Exhibit A), a summary of community engagement and communication is outlined, as there were concerns relating to the excavating of soils on the edge of Middle Twin Lake. As the cleanup plan calls for the majority of excavation activities to occur within at least 15-feet from the edge of the Middle Twin Lake, silt fencing (e.g. floating silt curtains) will be placed around most of the perimeter of the Subject Property, and sheet piling installed to a depth of approximately 10 feet in select areas to serve as a perimeter control for any stormwater runoff from the soils to Middle Twin Lake. Following excavation, clean fill will be placed on-site and the Subject Property will be restored. A permanent fence will be installed surrounding the perimeter of the largest parcel (adjacent to Middle Twin Lake). After fill has been placed on site, native seed mixes intended for emergent wetland, riparian floodplain, upland and dry prairies, will be planted to control erosion and recreate a landscaped environment. Additionally, enhanced landscaping would be provided along the southern portion of the Subject Property, and proposes the planting of native trees (averaging 6 to 8 feet in height) and shrub species that were selected to serve as a natural screening between the largest parcel and the adjacent residential neighborhood to the south (Twin Lake Avenue North). The Applicant has indicated plans to conduct the bulk of soil remediation and removals over the winter months as it will be more efficient and less messy with the freezing of wetland soils. The remainder of work is anticipated for completion in the spring of 2023. City staff requests a detail sheet be provided as part of any City permit application for the proposed fence, and that plan sets be updated and revised, as necessary to address comments as outlined in City Engineer Mike Alber’s memorandum, dated August 5, 2022 (Exhibit C). Given the residential nature of the neighborhood abutting the southern extent of the Subject Property, City staff requests the Applicant provide courtesy notification in advance of any work beginning on the Subject Property. In reviewing the proposal, it was determined by the Minnesota Pollution Control Agency (MPCA) that an Environmental Impact Statement (EIS) was not required, as the cleanup does not hit any of the thresholds that would trigger one. For this reason, and given that the proposed cleanup was already evaluated through the Superfund process, an EIS is not planned. SPECIAL USE PERMIT REVIEW The submittal, as contemplated under Planning Commission Application No. 2022-005 is a federal EPA (Environmental Protection Agency) mandated project that was delegated to the Minnesota Pollution Control Agency (MPCA) for oversight. As the MPCA typically tries to work with local municipalities and jurisdictions and their respective approval processes, the Applicant reached out to the City of Brooklyn Center for direction on what approvals and permits would be required to move forward given the directives outlined for remediation under the outlined Record of Decision. Due to site constraints, the Applicant will have temporary access rights via 4837 Azelia Avenue North (MSP Industrial) from October 2022 to June 2023. Due to the location of the Subject Property, a significant portion of this area is subject to a large floodplain boundary overlay and falls within the established (mapped) floodplain boundaries of the City. These App. No. 2022-005 PC 08/11/2022 Page 6 floodplain boundaries are determined and established under the city’s Federal Emergency Management Agency (FEMA) Flood Insurance Rate Maps (Map Panel No. 27053C0212F, effective as of November 4, 2016). These maps are used to determine potential floodplain impacts to adjacent properties, and regulate certain land uses and development standards within these districts. Refer to Image 4 below. Image 4. General Subject Property Location with Identified Floodplain (Credit: FEMA Map Service Center). City Code Section 35-2100 relates to the City’s floodplain management provisions. Within this ordinance, the City identifies three separate floodplain boundaries: 1) Floodway District; 2) Flood Fringe District; and 3) General Flood Plain District. The Flood Fringe Districts are those areas typically adjacent to floodways, and are commonly referred to as the “100-Year Floodplain”. These Flood Fringe/100-year areas are typically areas that may incur some flooding events, but are limited to 1% chance of flooding each year or an abnormal rainfall event. Standards for Flood Fringe District The standards for the Flood Fringe District are found under City Code Section 35-2100, Subsection 5. Under this section, the “placement of fill” (over 1000 cubic yards) is only permitted through issuance of a Special Use Permit. The Record of Decision on file for the Subject Property (Operable Unit 5) denotes the, “excavation of shallow soils with dioxin concentrations above the selected cleanup goals to depths of one to four feet, from the West Area and the Southern Lots (approximately 30,000 cubic yards). Of this, approximately 10,000 cubic yards would be consolidated on-site, with the remaining approximately 20,000 cubic yards taken off-site and disposed of at a Subtitle D landfill. This same section also provides specific “Standards for Flood Fringe Special Uses”, which are noted as follows (and are applicable to the requested use): App. No. 2022-005 PC 08/11/2022 Page 7 4. Standards for Flood Fringe Special Uses d. The placement of more than 1,000 cubic yards of fill or other similar material on a parcel (other than for the purpose of elevating a structure to the regulatory flood protection elevation) must comply with an approved erosion/ sedimentation control plan. 1) The plan must clearly specify methods to be used to stabilize the fill on site for a flood event at a minimum of the regional (1% chance) flood event. 2) The plan must be prepared and certified by a registered professional engineer or other qualified individual acceptable to the City. 3) The plan may incorporate alternative procedures for removal of the material from the floodplain if adequate flood warning time exists. The Applicant indicates in their submitted narrative (Exhibit A) that, “the purpose of this application is to obtain a Special Use Permit from the City of Brooklyn Center. To achieve remedial objectives and site restoration described in Section 1.1, grading/filling and construction of a permanent fence within the floodplain is required. Compensatory floodplain storage will be created to offset floodplain loss caused by filling. The remedial work is driven by a Response Order by Consent issued by the MPCA to the applicant on May 30, 1985. In July 2018, the MPCA issued a Record of Decision that selected the remedy for OU5, as described in Section 1.1.” The intent, as outlined by the Applicant, is to retain the Subject Property as undeveloped open space with a perimeter fence that prevents access by the general public. Per Section 35-2100, Subsection 10 (Administration) requirements, a permit is required prior to, “the placement of fill, excavation of materials, or the storage of materials or equipment within the floodplain.” COMPLIANCE FOR STANDARDS FOR SPECIAL USE PERMITS As noted previously, all Flood Fringe special uses shall be subject to the procedures and standards contained in Section 35-2100, Subsection 4 of the City’s Zoning Code, and are subject to the standards and procedures set forth in Subsection 10, Subpart 4. App. No. 2022-005 PC 08/11/2022 Page 8 ANALYSIS & FINDINGS OF SPECIAL USE PERMIT As part of the analysis formulated under this Special Use Permit application and report, City staff has the following additional responses and findings to the above-noted factors presented for consideration: 1) The danger to life and property due to increased flood heights or velocities caused by encroachments. City Staff Response: Staff does not believe the excavation and placement of fill as part of the proposed remediation work will create a dangerous situation to life and property as substantial removal of hazardous contaminants are being removed and the Subject Property is currently open land with no structures. The proposed work should not negatively impact the surrounding or immediate properties in this area as the work will take place exclusively on the Subject Property, and is in response to a Record of Decision relating to the Joslyn Superfund site. The Applicant has indicated that compensatory floodplain storage will be created to offset floodplain loss caused by the filling. 2) The danger that materials may be swept onto other lands or downstream to the injury of others or they may block bridges, culverts or other hydraulic structures. City Staff Response: Staff does not believe there will be any danger of materials onto other lands, as this project will exclusively impacting the contaminated soils of the Subject Property. The Applicant intends to utilize floating silt curtains and overall erosion control measures during the duration of the project. To minimize the impacts of these removals, the Applicant intends to conduct the majority of work during the winter months, and with the freezing of wetland soils. 3) The proposed water supply and sanitation systems and the ability of these systems to prevent disease, contamination, and unsanitary conditions. City Staff Response: The proposed project will have no effect upon the city water supply and/or sanitation systems in the City, and there are no plans to provide new connections as the Subject Property will continue to remain undeveloped. 4) The susceptibility of the proposed facility and its contents to flood damage and the effect of such damage on the individual owner. City Staff Response: Staff does not find this criterion applicable to the proposed Special Use remediation activities, as there are no plans to develop the Subject Property, the Property Owner (Applicant) is spearheading the project, and intends to retain ownership once all work is completed. 5) The importance of the services provided by the proposed facility to the community. City Staff Response: The proposed remediation work is necessary due to the contamination of soils on the Subject Property and the human health and environmental risks they pose. The remediation objectives for the Subject Property are intended to minimize the “incidental ingestion and direct contact with surface soils that contain concentrations of COCs above the soil cleanup goals and controlling future releases of contaminants to ensure protection of human health and the environment.” The proposed work will provide important public health and safety remediation work for the App. No. 2022-005 PC 08/11/2022 Page 9 community, removing contaminated soil from a designated Superfund site, and limiting the potential of exposure and release of chemical contaminants in the future. Although this work is mandated, the Applicant conducted some community engagement back in 2017, and revised plan sets based on feed back received to double the number of trees and shrubs planted, incorporate native species, and revise seed mixes. 6) The requirements of the facility for a waterfront location. City Staff Response: There are no facilities proposed as a part of the remediation activities. The remediation proposal must occur on the Subject Property due to the contamination of the soils and the health and environmental risks posed. The remedial work is driven by a Response Order by Consent issued by MPCA to the Applicant in 1985. In 2018 the MPCA selected the remediation plan for the Subject Property as described in the application materials, and as outlined in the Record of Decision. 7) The availability of alternative locations not subject to flooding for the proposed use. City Staff Response: Staff does not find this criterion applicable to the proposed Special Use remediation activities, as the remediation must occur on the Subject Property. 8) The compatibility of the proposed use with existing development and development anticipated in the foreseeable future. City Staff Response: The proposed remediation activity will only take place on the Subject Property, although the Applicant will work under temporary access provisions with neighboring 4837 Azelia Avenue North due to site constraints. The adjacent and surrounding properties have already been developed, including residential uses to the south and light industrial to the east. The Subject Property will remain under ownership by the Applicant and will be industrially-zoned, or residentially-zoned open space. There are no plans to redevelop the Subject Property, and the submitted documentation indicates the establishment of institutional controls (e.g. restrictive covenants) to restrict future land use and groundwater use within the provided Record of Decision. The large western property will not be accessible to the general public, and will have a perimeter fence. There are no proposed changes to the current land use of the properties after completion of the remediation work. 9) The relationship of the proposed use to the comprehensive plan and flood plain management program for the area. City Staff Response: The City of Brooklyn Center utilizes its Floodplain Management section, as outlined under Section 35-2100 of the City Code, to promote the public health, safety, and general welfare and to minimize potential losses due to flooding hazards. This ordinance is adopted to comply with the rules and regulations of the National Flood Insurance Program (NFIP) and Watershed Management Commission Rules. There are no plans to redevelop the Subject Property and the Applicant intends to retain ownership of said property. As the aforementioned property is substantially impacted by the 100-year floodplain, as well as wetlands, City staff does not anticipate any future redevelopment of the Subject Property, and the provided Record of Decision indicates App. No. 2022-005 PC 08/11/2022 Page 10 the implementation of institutional controls that would further restrict any future redevelopment. With that said, and given the work proposed within the 100-year floodplain, the Applicant will need to apply for and receive issuance of a Land Alteration (Disturbance) Permit, as outlined within Section 35-2100, to ensure the provision of a satisfactory erosion control and grading plan, and SWPPP best practices during the removal of soils and provision of clean fill. As proposed, there are no plans to reduce the storage capacity of the present floodplain. The Shingle Creek Watershed Commission reviewed the project application in 2017 and approved the project with no addition conditions. City staff reached out to the Watershed Commission to verify whether there were any expiration dates attached to the approvals of projects—the Watershed Commission responded that there were indeed no time limits in terms of beginning work once a project was approved; however, City staff is requesting the Applicant provided updated plan sets to the Commission for their record. 10) The safety of access to the property in times of flood for ordinary and emergency vehicles. City Staff Response: The Subject Property is currently accessible via Twin Lake Avenue North and via the parking lot of 4837 Azelia Avenue North. An existing fire access road wraps around the industrial building located at 4837 Azelia Avenue North and runs parallel to the existing perimeter fence in place on the largest parcel of the Subject Property, with Middle Twin Lake located to the west. The southern lots can be accessed via Twin Lake Avenue North. There should be little if any need to access the Subject Property once remediation work is completed. There will be a permanent perimeter fence installed as a part of the proposed project, and the Applicant indicates no future plans to redevelop the Subject Property. 11) The expected heights, velocity, duration, rate of rise, and sediment transport of the flood waters expected at the site. City Staff Response: Staff does not find this criterion applicable to the proposed Special Use remediation activities. The remediation activities will provide the necessary fill to offset any floodplain loss during excavation and removal of contaminated soils, and upon completion, should have little if any effect upon the expected heights, water velocities or sediment transport of any potential floodwaters at this site. During the course of this work, the Applicant intends to implement SWPPP measures. 12) Such other factors which are relevant to the purposes of this Ordinance. City Staff Response: Staff believes there are no other factors or issues to comprehend on this project. The Applicant has indicated that the proposed remediation plan had been has been reviewed by the Shingle Creek Watershed Management Commission, Minnesota Wetland Conservation Act, and Minnesota Department of Natural Resources. App. No. 2022-005 PC 08/11/2022 Page 11 General Special Uses Criteria 1. The establishment, maintenance, or operation of the special use will promote and enhance the general public welfare and will not be detrimental to or endanger the public health, safety, morals, or comfort. City Staff Response: The proposed remediation enhances general public welfare by working to prevent exposure and contact with contaminated surface soils associated with the previous uses of this property, and mitigating future releases. Although this is a mandated project operating under the approved Record of Decision, the Applicant conducted some community engagement work to address concerns relating to the removals of contaminated soils, and clear-cutting of trees along Middle Twin Lake. The plan sets were revised based on feedback to provide additional trees and shrubs, native plantings and seed mixes. A permanent fence will be installed. 2. The special use will not be injurious to the use and enjoyment of other property in the immediate vicinity for the purposes already permitted, nor substantially diminish and impair property values within the neighborhood. City Staff Response: The proposed remediation work will only take place on the Subject Property and address contaminated soils identified as OU5, although temporary access provisions are necessary between October 2022 and June 2023 and through 4837 Azelia Avenue North due to site constraints. The remediation activities proposed includes installation of a permanent fence (currently existing) and includes a landscaping plan that provides visual screening from the Subject Property and the adjacent residential neighborhood through the planting of trees and shrubs. 3. The establishment of the special use will not impede the normal and orderly development and improvement of surrounding property for uses permitted in the district. City Staff Response: As stated above, the proposed remediation activity will only take place on the Subject Property. The adjacent and surrounding properties have already been developed, including residential uses to the south and light industrial to the east, but City staff has requested that the Applicant provide notification to those properties in proximity to the Subject Property and in advance of any work. The Applicant intends to conduct the majority of work over the winter months to minimize impacts associated with the remediation. 4. Adequate measurements have been or will be taken to provide ingress, egress, and parking so designed as to minimize traffic congestion in the public streets. City Staff Response: Staff does not find this criterion applicable to the proposed Special Use request, as the Subject Property will not be accessible to the general public. The properties will remain under Joslyn ownership and will be industrially-zoned open space. With that said, City staff requests a pre-construction conference in advance of any work beginning to address haul routes and impacts with the use of construction equipment (e.g. dump trucks), SWPPP measures, and notifications to neighboring owners and residents. 5. The special use shall, in all other respects, conform to the applicable regulations of the district in which it is located. City Staff Response: The Applicant has indicated that the proposed remediation plan has been has been reviewed by the Shingle Creek Watershed Management Commission, Minnesota Wetland Conservation Act, and Minnesota Department of Natural Resources. As the existing Subject Property is currently undeveloped and plans to remain undeveloped, it is anticipated that App. No. 2022-005 PC 08/11/2022 Page 12 the use (i.e. that being the soil remediation project) will conform to the applicable regulations of the district, as well as the conditions of approval for any other permits and approvals required by external agencies (e.g. Shingle Creek Watershed Commission, MPCA, MN DNR). The Applicant also provided responses to the general Standards of Special Use Permits, which are reflected below and in Exhibit A: ANTICIPATED PERMITTING | APPROVAL CONDITIONS Staff recommends the following conditions be attached to any positive recommendation on the approval of Application No. 2022-005 for the Subject Property (identified as Property IDs 10-118-21-23-0007, 10- 118-21-32-0058, and 10-118-21-32-0059): App. No. 2022-005 PC 08/11/2022 Page 13 1. The Applicant shall apply for and receive issuance of a City Grading/Land Disturbance permit from the City of Brooklyn Center prior to the start of any work. 2. The Applicant agrees to comply with all conditions, provisions, and requests for revisions and additional plan sets as noted in the City Engineer’s review memorandum, dated August 5, 2022. a. Complete and revised plans shall be submitted for review, including: existing conditions, access and staging, removals, site plan, grading, drainage, and erosion control plans, and any other site engineering related issues are subject to review and approval by the City Engineer prior to the issuance of permits. b. Revise location of the permanent fence and landscape screening to be located outside of the existing City right-of-way at the north end of Twin Lake Avenue North. c. A pre-construction conference shall be scheduled and held with City staff and other entities designated by the City. 3. Applicant shall obtain approvals from external agencies, as necessary, including the Shingle Creek Watershed Management Commission, Minnesota Wetland Conservation Act, and Minnesota DNR, as well as any conditions outlined in the Notice of Decision for Wetland Replacement Plan and Public Waters Work Permit. RECOMMENDATION Based on the above-noted findings and conditions, City staff recommends: The Planning Commission recommends City Council approval of the requested issuance of a Special Use Permit for work within the 100-year floodplain for the Subject Property identified under the following Property IDs: 10-118-21-23-0007, 10-118-21-32-0058, and 10-118-21-32-0059; and subject to the Applicant complying with the comments outlined in the Approval Conditions noted above. ATTACHMENTS Exhibit A – Planning Commission Application No. 2022-005 Plans and Documents, submitted July 11, 2022. Exhibit B – Public Hearing Notice, published in the Brooklyn Center Sun Post, and dated July 28, 2022. Exhibit C – Review Memorandum, prepared by City Engineer Mike Albers, and dated August 5, 2022. Barr Engineering Co. 4300 MarketPointe Drive, Suite 200, Minneapolis, MN 55435 952.832.2600 www.barr.com Memorandum To: City of Brooklyn Center Planning and Zoning Division From: Eric Lund, PE, Barr Engineering Co. Subject: Special Use Permit Application – Joslyn OU5 Remediation Project Date: July 11, 2022 Project: 23270110 On behalf of Joslyn Manufacturing Company, Barr Engineering Co. has prepared this Special Use Permit application for a planned soil remediation project required as part of continuing Superfund cleanup efforts for the Joslyn Site. The following sections address application requirements detailed in the Special Use Permit Procedures and Application Checklist, provided by the City of Brooklyn Center. 1 Project Narrative 1.1 Description of Project The Joslyn Site was used for wood-treating operations from the 1920s until its closure in 1980. The Joslyn Site is divided into two primary areas: the eastern portion, which has been redeveloped for light industrial use under MPCA oversight and partially delisted from the Superfund program, and the undeveloped western portion, known as the West Area. The West Area remains on the MPCA’s Permanent List of Priorities (PLP) and the USEPA’s National Priorities List (NPL). The project site (Operable Unit 5, OU5) is comprised of the West Area and two Joslyn-owned residential lots (Southern Lots) that are south-adjacent to the West Area (Figure 1). Dioxins are the primary chemical of concern (COC) for the site and drive human health and ecological risk. Remediation objectives for the Site include preventing incidental ingestion and direct contact with surface soils that contain concentrations of COCs above the soil cleanup goals and controlling future releases of contaminants to ensure protection of human health and the environment. To meet the remedial objectives, shallow soils with chemical concentrations above clean up goals will be excavated and either consolidated onsite or transported to an offsite facility for disposal. After excavation, clean fill will be placed and OU5 will be restored. Following remediation, Joslyn intends to maintain ownership of both the Southern Lots and the West Area. The assumed future land uses are residentially zoned open space for the Southern Lots and industrially-zoned, fenced open space for the West Area. 1.2 Nature of the Applicant’s Interest The purpose of this application is to obtain a special use permit from the City of Brooklyn Center. To achieve remedial objectives and site restoration described in Section 1.1, grading/filling and construction of a permanent fence within the floodplain is required. Compensatory floodplain storage will be created to offset floodplain loss caused by filling. The remedial work is driven by a Response Order by Consent Exhibit A To: City of Brooklyn Center Planning and Zoning Division From: Eric Lund, PE, Barr Engineering Co. Subject: Special Use Permit Application – Joslyn OU5 Remediation Project Date: July 11, 2022 Page: 2 P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\Permitting\City\Permit App Memo\Permit Application Memo_text.docx issued by the MPCA to the applicant on May 30, 1985. In July 2018, the MPCA issued a Record of Decision that selected the remedy for OU5, as described in Section 1.1. 1.3 Intended Use of the Property The intended use of OU5 post-remediation is to remain an undeveloped, open space with a perimeter fence, inaccessible to the general public. Joslyn intends to retain ownership of both the West Area and Southern Lots. The proposed use of OU5 meets the Criteria to Review listed on the Special Use Permit Procedures and Application Checklist, as shown in the table below. Criteria to Review Intended Use The establishment, maintenance or operation of the special use will promote and enhance the general public welfare and will not be detrimental to or endanger the public health, safety, morals or comfort. The proposed remediation enhances general public welfare by preventing incidental ingestion and direct contact with surface soils that contain contaminants associated with the former wood-treating operations and controlling future releases. The special use will not be injurious to the use and enjoyment of other property in the immediate vicinity for the purposes already permitted, nor substantially diminish and impair property values within the neighborhood. The proposed remediation work will address impacted soils associated with a Superfund site. The remediation activities only take place within the OU5 boundaries and include a visual screening of trees and shrubs between the site and the adjacent neighborhood. The establishment of the special use will not impede the normal and orderly development and improvement of surrounding property for permitted uses. The proposed remediation work will only take place within the OU5 boundaries. Surrounding properties have already been developed for light industrial and residential use. Adequate measures have been or will be taken to provide ingress, egress and parking so designed as to minimize traffic congestion in the public streets. This criterion is not applicable, as OU5 will not be accessible to the general public. The special use shall, in all other respects, conform to the applicable regulations of the district in which it is located. The proposed remediation work conforms to applicable regulations and has previously received the appropriate reviews and permits from Shingle Creek Watershed Management Commission, Minnesota Wetland Conservation Act, and Minnesota Department of Natural Resources. Note that the Notice of Decision for the Wetland Replacement Plan and the Public Waters Work Permit have expiration dates in 2022. Permit extensions have been applied for and are expected to be received. To: City of Brooklyn Center Planning and Zoning Division From: Eric Lund, PE, Barr Engineering Co. Subject: Special Use Permit Application – Joslyn OU5 Remediation Project Date: July 11, 2022 Page: 3 P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\Permitting\City\Permit App Memo\Permit Application Memo_text.docx 2 Site Information, Utilities, and Infrastructure OU5 is comprised of wetlands and wooded upland. To the south of OU5 is a residential neighborhood, to the west is Middle Twin Lake, to the north is a Canadian Pacific railroad corridor, and to the east is a fully built-out light industrial/commercial development. There are no structures present in the West Area with exception to a perimeter fence and two storm sewer outfalls. A boundary survey of OU5 is included as Attachment 1 and consists of the following parcels: • West Area – 11.1 Acres, County Parcel ID 1011821230007 • Southern Lots – 0.56 Acres total, County Parcel IDs 1011821320058 and 1011821320059 The existing site plan; including property lines, topography, utilities, and features are shown on Figure 1. The proposed plan; including topography, utilities, features, and surface water flow is shown on Figure 2. There is no proposed change to property lines. 3 Restoration/Landscaping Plan After backfill has been placed, native seed mixes will be planted to create a diverse, vibrant ground plain to control erosion and create a valuable habitat. Several seed mixes, all designed by MN/DOT, are planned, ranging from emergent wetland seed mixes, riprairan floodplain seed mixes, and upland and dry prairie mixes. Native and pollinator friendly seed mixes have been selected in order to provide an enhanced habitat environment after remediation. In addition, a variety of tree and shrub species will be planted to provide a visual screening between the site and the adjacent neighborhood. A new perimeter fence will be installed around the OU5 boundaries to replace the existing fence. The restoration/ landscaping plan is shown on Figures 3a and 3b. Enclosures Figure 1 Existing Conditions Figure 2 Proposed Final Grading Plan Figure 3 Restoration and Screening Plan Attachment 1 Boundary and Location Survey Figures Attachments Brooklyn Center • Brooklyn Park • Crystal • Maple Grove • Minneapolis • New Hope • Osseo • Plymouth • Robbinsdale Watershed Management Commission 3235 Fernbrook Lane N • Plymouth, MN 55447 Phone (763) 553-1144 • Fax (763) 553-9326 www.shinglecreek.org June 12, 2017 Steve Lillehaug City of Brooklyn Center via email 6301 Shingle Creek Parkway Brooklyn Center, MN 55430 Re: Project Review SC2017-003 Joslyn Manufacturing Superfund Site OU5 Dear Mr. Lillehaug: At their meeting of June 8, 2017, the Shingle Creek Watershed Management Commission reviewed the above-referenced project. The City of Brooklyn Center is hereby notified that Project Review SC2017-003 was approved with no conditions. A copy of the engineer’s report is enclosed. Should you have any questions, please contact Ed Matthiesen at Wenck Associates, 763.252-6851. Sincerely, Judie A. Anderson Administrator JAA:tim encls. Cc via email: Dale Finnesgaard, Barr Engineering David Mulla, Commissioner Ed Matthiesen, Wenck Associates Project file Z:\Shingle Creek\Project Reviews\Projects 2017\L_2017-003_BC.doc Page 1 of 4 May 25, 2017 SHINGLE CREEK WATERSHED MANAGEMENT COMMISSION PROJECT REVIEW SC2017-003: Joslyn Manufacturing & Supply Co. Superfund Site, OU5 Owner: Joslyn Manufacturing Company 1500 Mittel Blvd. Wood Dale, IL 60191 Engineer: Dale Finnesgaard Company: Barr Engineering Address: 4300 MarketPoint Drive, Suite 200 Minneapolis, MN 55435 Phone: 952-832-2667 Email: dfinnesgaard@barr.com Purpose: Remediation of contaminated soils through excavation and onsite consolidation and cover. Project with affect both MNDNR and WCA regulated wetlands and will require fill in floodplain. Location: Intersection of Zelia Ave. N and Lakebreeze Ave N, Brooklyn Center, MN (Figure 1). Exhibits: 1. Project review application and project review fee of $3,700, dated 05/11/17, rcvd. 05/17/17. 2. Site plan, excavation, consolidation, grading, stormwater management and restoration plans, and hydrologic calculations by Barr Engineering, dated May 2017, rcvd. 05/17/17. Findings: 1. The proposed project is the remediation of contaminated soils through excavation and onsite consolidation and cover. Specifically, 8.3 acres of the 11.7-acre site will be excavated (Figure 2). Of those 8.3 acres, approximately 3.5 acres will be excavated and consolidated (with 1.3 acres of contaminated soil remaining in place under the consolidation area) and 4.8 acres will be disposed in a Subtitle D Landfill. No new impervious areas area will be added to the site as a result of this project, and the site will remain 0 percent impervious. 2. The complete Project Review was received on 05/17/17. To comply with the 60- day review requirement, the Commission must approve or deny this project no later than the 07/13/17 meeting. Sixty calendar-days expires on 07/16/17. 3. To comply with the Commission’s water quality treatment requirement, the site must provide ponding designed to NURP standards with dead storage volume equal to or greater than the volume of runoff from a 2.5” storm event, or BMPs providing a similar level of treatment - 80-85% TSS removal and 50-60% TP removal. If a sump is used the MnDOT Road Sand particle size distribution is acceptable for 80% capture. Runoff from the site is proposed to be routed to several low-lying wetland areas, which remove approximately 95 percent TSS and 66 percent TP, according to a P8 model. The applicant meets Commission water quality treatment requirements. 4. Commission rules require that site runoff be limited to existing rates for the 2-, 10- , and 100-year storm events. Runoff from the site is proposed to be routed to the southern wetland. Proposed runoff rates fall below existing runoff rates due to SC2017-003: Joslyn Manufacturing & Supply Co. Superfund Site, OU5 Page 2 of 4 \\Ci.brooklyn-center.mn.us\BCfiles\Community Development\Planning\Planning Commission - Applications and Docs\2022\2022-005_Joslyn Superfund Site_SUPLAP\Application and Documentation\2017-003_BCJoslynSite_WatershedCommission_ProjectReview.doc proposed increased storage within the southern wetland (Figure 2, see “Floodplain Mitigation Area”). The applicant meets the Commission’s rate control requirements (Table 1). Table 1. Runoff from site (cfs). Drainage Area 2-year event 10-year event 100-year event Pre- Post- Pre- Post- Pre- Post- Entire site 10 5 32 16 122 94 5. Commission rules require the site to infiltrate 1.0” of runoff from new impervious area within 48 hours. There is no new impervious area proposed for this site. Therefore, the applicant meets Commission volume control requirements. 6. The NWI identifies a wetland on site. The Shingle Creek Watershed Management Commission is LGU for WCA administration. A wetland delineation was carried out on October 17, 2007 and updated on October 23, 2012. A 9.01-acre wetland was delineated. The proposed project requires 5.50 acres of temporary impacts to this wetland, which qualify for No-Loss Criteria, and 0.78 acres of permanent wetland impacts, which will be mitigated through the purchase of wetland credits. In addition, wetland buffers averaging 30 feet in width are provided. All buffers are a minimum of 20 feet, with two exceptions that cannot be avoided. The first exception is in the southern portion of site, near the corner of the fence line adjacent to Twin Lake Avenue N. Due to the location of the existing road, the 20- foot minimum buffer cannot be met in this corner. The second exception is in the northern portion of the site. The wetland extends beyond the work area into the railroad right-of-way. Joslyn has no access to the adjacent upland buffer within this right of way and therefore cannot designate this area as a buffer strip. The applicant meets Commission wetland requirements. 7. Middle Twin Lake is listed as a Public Water on site, and the applicant has submitted a Work in Public Waters permit application to the MDNR. 8. There is floodplain on this site, and the proposed project will result in 4,897 cubic yards of permanent fill within the 100-year floodplain. However, 5,554 cubic yards of compensatory storage will be provided through excavation, exceeding the floodplain fill volume by approximately 660 cubic yards. The applicant meets Commission floodplain requirements. 9. An erosion control plan was submitted with the project review, and includes a rock construction entrance, perimeter silt fence, flotation silt curtain, and sheet piling, as well as several permanent erosion control measures. The erosion control plan meets Commission requirements. 10. A public hearing on the project was conducted on 04/12/17 as part of Planning Commission and City Council review of this project, meeting Commission public notice requirements. 11. A Project Review Fee of $3,700 has been received. SC2017-003: Joslyn Manufacturing & Supply Co. Superfund Site, OU5 Page 3 of 4 \\Ci.brooklyn-center.mn.us\BCfiles\Community Development\Planning\Planning Commission - Applications and Docs\2022\2022-005_Joslyn Superfund Site_SUPLAP\Application and Documentation\2017-003_BCJoslynSite_WatershedCommission_ProjectReview.doc Recommendation: Recommend approval with no conditions. Wenck Associates, Inc. Engineers for the Commission _________________June 12 2017_____________________________ Ed Matthiesen, P.E. Date Figure 1. Site location. SC2017-003 SC2017-003: Joslyn Manufacturing & Supply Co. Superfund Site, OU5 Page 4 of 4 \\Ci.brooklyn-center.mn.us\BCfiles\Community Development\Planning\Planning Commission - Applications and Docs\2022\2022-005_Joslyn Superfund Site_SUPLAP\Application and Documentation\2017-003_BCJoslynSite_WatershedCommission_ProjectReview.doc Figure 2. Excavation and grading plan. All shaded areas will be excavated. Figure 3. Restoration plan showing two exceptions to 20-foot minimum wetland buffer rule. 4300 MarketPointe Drive, Suite 200 Minneapolis, MN 55435 952.832.2600 www.barr.com Permit Application for Stormwater, Floodplain, and Wetland Alteration OU5 Remediation Project Joslyn Manufacturing & Supply Co. Site Brooklyn Center, Minnesota Prepared for Joslyn Manufacturing Company May, 2017 P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\Permitting\Combined Agency Permit Application_OU5\Text\Joslyn_OU5 Joint Permit Application_Final.docx i Permit Application for Stormwater, Floodplain, and Wetland Alteration OU5 Remediation Project: Joslyn Manufacturing & Supply Co. Site May, 2017 Contents 1.0 Introduction ........................................................................................................................................................................... 1 1.1 Background ....................................................................................................................................................................... 1 1.1.1 MPCA Consent Order and Record of Decision .............................................................................................. 1 1.1.1.1 Operable Units 1 Through 4 ....................................................................................................................... 1 1.1.2 Site Redevelopment ................................................................................................................................................. 2 1.1.2.1 Operable Unit 5 ................................................................................................................................................ 3 2.0 Existing Conditions .............................................................................................................................................................. 5 2.1 West Area ........................................................................................................................................................................... 5 2.1.1 Existing Land Use ....................................................................................................................................................... 5 2.1.1.1 Sub-Areas ........................................................................................................................................................... 5 2.1.2 Existing Stormwater Management ..................................................................................................................... 6 2.1.3 Existing Floodplain .................................................................................................................................................... 7 2.2 Southern Lots ................................................................................................................................................................... 7 2.2.1 Existing Land Use ....................................................................................................................................................... 7 2.2.2 Existing Floodplain .................................................................................................................................................... 7 2.2.3 Existing Stormwater Management ..................................................................................................................... 7 3.0 Remediation and Mitigation Work ............................................................................................................................... 8 3.1 Remediation Objectives ............................................................................................................................................... 8 3.2 Remediation Alternatives ............................................................................................................................................ 8 3.3 Remediation and Mitigation Work Plan ................................................................................................................ 9 3.3.1 Erosion and Sediment Control ...........................................................................................................................10 3.3.2 Clearing and Grubbing ..........................................................................................................................................11 3.3.3 Stormwater Management ....................................................................................................................................11 3.3.4 Access Roads .............................................................................................................................................................11 3.3.5 Consolidation of Soils into Onsite Consolidation Area ............................................................................11 3.3.6 Excavation and Backfill of Contaminated Areas ..........................................................................................11 ii 3.3.7 Floodplain Mitigation ............................................................................................................................................11 3.3.8 Wetland Mitigation .................................................................................................................................................11 3.3.9 Site Restoration ........................................................................................................................................................12 3.3.10 Inspection and Maintenance ..............................................................................................................................12 3.4 Remediation Schedule ................................................................................................................................................12 4.0 Stormwater Management ..............................................................................................................................................13 4.1 Stormwater Design.......................................................................................................................................................13 4.1.1 Temporary Stormwater Management .............................................................................................................13 4.1.1.1 Sheet Piling ......................................................................................................................................................13 4.1.1.2 Building 1B Pond Outlet Removal ..........................................................................................................13 4.1.2 Permanent Stormwater Management .............................................................................................................13 4.1.2.1 Sewer Piping ....................................................................................................................................................14 4.1.3 Permanent Stormwater Treatment BMPs ......................................................................................................14 4.2 Hydrologic and Hydraulic Analysis ........................................................................................................................14 4.2.1 Modeling Methodology ........................................................................................................................................14 4.2.2 Model Inputs .............................................................................................................................................................15 4.2.3 Modeling Results .....................................................................................................................................................16 4.3 Water Quality Analysis ................................................................................................................................................17 4.3.1 Modeling Methodology ........................................................................................................................................17 4.3.2 Model Inputs .............................................................................................................................................................17 4.3.3 Modeling Results .....................................................................................................................................................18 4.4 TMDL Implementation Plan Compliance ............................................................................................................19 4.5 Maintenance ...................................................................................................................................................................19 5.0 Erosion and Sediment Control .....................................................................................................................................20 5.1 Construction Schedule ................................................................................................................................................20 5.2 Dewatering ......................................................................................................................................................................20 5.3 Temporary Erosion and Sediment Control .........................................................................................................20 5.3.1 Sheet Piling ................................................................................................................................................................20 5.3.2 Construction Fence .................................................................................................................................................21 5.3.3 Silt Fence .....................................................................................................................................................................21 5.3.4 Flotation Silt Curtain ...............................................................................................................................................21 5.3.5 Rock Construction Entrance ................................................................................................................................21 5.3.6 Equipment Decontamination Area ...................................................................................................................21 5.3.7 Street Sweeping .......................................................................................................................................................21 iii 5.3.8 Grade Breaks .............................................................................................................................................................21 5.3.9 Stabilization ...............................................................................................................................................................21 5.3.10 Rock Check Dams ....................................................................................................................................................22 5.4 Permanent Erosion and Sediment Control .........................................................................................................22 5.4.1 Riprap ...........................................................................................................................................................................22 5.5 Site Restoration .............................................................................................................................................................22 5.6 Inspections and Maintenance ..................................................................................................................................22 5.6.1 Frequency ...................................................................................................................................................................22 5.6.2 Recording ...................................................................................................................................................................22 5.6.3 Maintenance Measures .........................................................................................................................................23 5.6.3.1 Silt Fence ...........................................................................................................................................................23 5.6.3.2 Construction Vehicle Exit Locations .......................................................................................................23 5.6.3.3 Surface Water Conveyance Systems ......................................................................................................23 5.7 Removal ............................................................................................................................................................................23 6.0 Floodplain Management.................................................................................................................................................24 6.1 OU5 Floodplain Fill .......................................................................................................................................................24 6.2 Compensatory Storage ...............................................................................................................................................24 7.0 Wetland Alteration ............................................................................................................................................................26 7.1 Wetland Delineation and Classification Methods ............................................................................................26 7.2 Wetland Description ....................................................................................................................................................27 7.3 Historical Imagery Review .........................................................................................................................................27 7.3.1 West Area ...................................................................................................................................................................27 7.4 Agency Meetings ..........................................................................................................................................................28 7.4.1 2007 TEP Meeting ...................................................................................................................................................28 7.4.2 2012 TEP Meetings .................................................................................................................................................28 7.5 Sequencing Analysis ....................................................................................................................................................29 7.5.1 No Action Alternative (Alternative 1)...............................................................................................................30 7.5.2 Stormwater Management Modifications (Alternative 2) .........................................................................30 7.5.3 Excavation for Offsite Treatment and Disposal (Alternative 3) .............................................................31 7.5.4 In-Place Soil Cover (Alternative 4) ....................................................................................................................31 7.5.5 Onsite Consolidation with Soil Cover at West Area (Alternative 5) .....................................................31 7.5.6 Onsite Consolidation with Soil Cover at Azelia Avenue Pond (Alternative 6) .................................31 7.5.7 Limited Onsite Consolidation with Soil Cover at Building 1A Pond (Alternative 7) ......................32 7.5.8 Proposed Alternative – Limited Onsite Consolidation with Soil Cover (Alternative 8) ................32 iv 7.5.9 Wetland Impact Minimization ............................................................................................................................33 7.6 Wetland Impacts and Mitigation ............................................................................................................................33 7.6.1 Wetland Impacts ......................................................................................................................................................33 7.6.2 Wetland Mitigation .................................................................................................................................................35 7.7 Adjoining Property Owners ......................................................................................................................................36 7.8 Portion of Work Completed .....................................................................................................................................36 7.9 Status of Other Approvals .........................................................................................................................................36 7.10 Special Considerations................................................................................................................................................36 7.10.1 Endangered and Threatened Species ..............................................................................................................36 7.10.2 Rare Natural Communities ..................................................................................................................................37 7.10.3 Special Fish and Wildlife Resources .................................................................................................................37 7.10.4 Cultural Resources ..................................................................................................................................................37 7.10.5 Groundwater Sensitivity ........................................................................................................................................37 7.10.6 Sensitive Surface Waters ......................................................................................................................................37 7.10.7 Education or Research Use ..................................................................................................................................37 7.10.8 Waste Disposal Sites ..............................................................................................................................................37 7.10.9 Consistency with Other Plans .............................................................................................................................37 8.0 Construction Sequencing ...............................................................................................................................................38 9.0 References ............................................................................................................................................................................40 v List of Tables Table 1 SCWMC Rainfall Depths ................................................................................................................................ 15 Table 2 Stormwater Modeling Results – Peak Runoff Rate ............................................................................. 16 Table 3 Stormwater Modeling Results – South Wetland Flood Water Elevations ................................. 16 Table 4 Water Quality Modeling Results ................................................................................................................ 18 Table 5 Fill and Compensatory Storage Volumes ............................................................................................... 24 Table 6 Wetland Impact Areas and Floodplain Fill Volumes .......................................................................... 30 Table 7 Comparative Evaluation of Remedial Alternatives ………………………………………………... attached List of Figures Figure 1 Site Location Map Figure 2 Land Parcels Figure 3 Site Layout Figure 4 Existing Stormwater Management Figure 5 Existing Drainage Areas Figure 6 Proposed Drainage Areas List of Appendices Appendix A Joint Application Form Appendix B SCWMC Project Review Application Form Appendix C Construction Drawings Appendix D Construction Specifications Appendix E Stormwater Modeling Output Appendix F Wetland Delineation Report Appendix G Wetland Delineation Approval Appendix H 1999 MDNR Letter Describing Jurisdiction Appendix I Historical Aerial Imagery Appendix J Wetland Community Impact by Alternatives Appendix K MNRAM Comparison Appendix L Application for Withdrawal of Wetland Banking Credits Appendix M SHPO Database Review Results vi Acronyms & Abbreviations ARARs Applicable and/or Relevant and Appropriate Requirements Barr Barr Engineering Company BAZ Bioactive Zone BMPs Best Management Practices BWSR Minnesota Board of Water & Soil Resources CERCLA Comprehensive Environmental Response, Compensation, and Liability Act CMP Corrugated Metal Culvert Comprehensive Plan City of Brooklyn Center’s Comprehensive Plan for 2020 DFIRM Digital Flood Insurance Rate Map DNAPL Dense Non-Aqueous Phase Liquid FEMA Federal Emergency Management Agency FIRM Flood Insurance Rate Map HCD Hennepin Conservation District IZ Isolation Zone Joslyn Site Joslyn Manufacturing & Supply Co. Site LTU Land Treatment Unit MDNR Minnesota Department of Natural Resources MERLA Minnesota Environmental Response and Liability Act MNRAM Minnesota Routine Assessment Method for Evaluating Wetland Functions MPARS MDNR Work in Public Waters Permit application MPCA Minnesota Pollution Control Agency MSL Mean Sea Level NCP National Contingency Plan NPDES National Pollutant Discharge Elimination System NPL National Priorities List NURP Nationwide Urban Runoff Program NWI National Wetland Inventory NWL Normal Water Level OHWL Ordinary High Water Level OU Operable Unit PAHs Polynuclear Aromatic Hydrocarbons PCP Pentachlorophenol PLP Permanent List of Priorities PRG Preliminary Remediation Goal PWI Public Waters Inventory vii ROD Record of Decision SCWMC Shingle Creek Watershed Management Commission SHPO Minnesota Historical Society State Historic Preservation Office TEP Technical Evaluation Panel USACE United States Army Corps of Engineers USEPA United States Environmental Protection Agency WA West Area WCA Minnesota Wetland Conservation Act 1 1.0 Introduction On behalf of Joslyn Manufacturing Company, Barr Engineering Co. (Barr) has prepared this Joint Water/Wetland permit application to the Shingle Creek Watershed Management Commission (SCWMC), Minnesota Department of Natural Resources (MDNR) and United States Army Corps of Engineers (USACE) for an onsite soil remediation project required as part of continuing Superfund cleanup efforts for the Joslyn Manufacturing & Supply Co. Site (Joslyn Site). A copy of this application is also being provided to the City of Brooklyn Center for their information as it relates to the City’s Land Disturbance Permit ordinance. The lead regulatory agency for this site is the Minnesota Pollution Control Agency (MPCA). Figure 1 shows the historic Joslyn Site and the project areas requiring permitting. The Joslyn Site is located within the NW quarter of Section 10 of Range 21 in Township 118, north of the intersection of Azelia Avenue North and Lakebreeze Avenue North in Brooklyn Center, Hennepin County, Minnesota. It is bounded by residential development to the south, Middle Twin Lake to the west, an active Canadian Pacific Railway track to the north, and State Highway 100 to the east. The permit areas include: • The West Area, the western portion of the Joslyn site adjacent to Middle Twin Lake, and • The Southern Lots, two residential lots that were added to the remediation requirements that are located just south of the West Area and outside the historic Joslyn Site boundary. In this report, the terms “Joslyn Site” or “Site” are used to refer to the entire Joslyn Manufacturing & Supply Co. Site property and the terms “West Area” and “Southern Lots” are used to refer to the portions of the property that comprise Operable Unit 5, described later in this Section. 1.1 Background From the 1920s until 1980, a succession of companies treated wooden poles and ties at the Joslyn Site. Soil, sediment, and groundwater at the Site became contaminated with pentachlorophenol (PCP), polynuclear aromatic hydrocarbons (PAHs), and/or dioxins/furans, which are constituents of the wood preservatives (Barr, 1996 and MPCA, 1985). 1.1.1 MPCA Consent Order and Record of Decision On May 30, 1985, the MPCA and Joslyn entered into a Response Order by Consent (Consent Order) to continue investigation and begin cleanup of the Joslyn Site (MPCA, 1985). After the order was given, implementation of interim response actions began, including excavating and disposing offsite some areas of significant soil contamination in 1988. 1.1.1.1 Operable Units 1 Through 4 Following the Consent Order, remedial investigation of the site found that the contaminated media requiring remediation on the Joslyn Site could be placed into four operable units, including: 2 • Operable Unit 1 (OU1) – Shallow ground water • Operable Unit 2 (OU2) – Middle sand ground water • Operable Unit 3 (OU3) – Dense non-aqueous phase liquid (DNAPL) • Operable Unit 4 (OU4) – Soil On July 31, 1989, a Record of Decision (ROD) specified the following remedies for the four operable units (MPCA, 1989): • Installation, operation, and maintenance of a groundwater pump-out system (OU1 and OU2), • Installation, operation, and maintenance of a DNAPL pump-out system (OU3), • Regional ground water and surface water monitoring (OU1, OU2, and OU3), and • Onsite biological treatment of the contaminated soil that remained after the 1988 interim response action (OU4). 1.1.2 Site Redevelopment In 1999, per the MPCA’s request, a prospective site redeveloper conducted a soil sampling program to assess the presence of PAHs, PCP, and dioxins/furans in accessible soils across the Joslyn Site. This study resulted in the Joslyn Site being divided into areas, with the West Area identified as an area requiring additional investigation and possible remediation. With the exception of the West Area, the Joslyn Site has now been redeveloped as part of three separate phases of redevelopment. Redevelopment activities were undertaken by Real Estate Recycling, Inc., with the cooperation of Joslyn and under the oversight of the MPCA. Three buildings were constructed for light industrial use, along with their associated parking lots, stormwater ponds, and an extension of Azelia Avenue. The groundwater and DNAPL remedies (OU1, OU2, and OU3) continue to operate effectively following redevelopment (MPCA, 2004a). Groundwater and lake level monitoring has been conducted at the Site for over 30 years, and data indicate that groundwater flows from Middle Twin Lake to the east-southeast. Water quality monitoring data indicates that the pump-out system has been effective in preventing the migration of contaminants to either the groundwater adjacent to or down gradient of the Site, or into the lower underlying aquifer. For the OU4 soil remedy, site redevelopment features (buildings, driveways, and areas of clean-vegetated soil) provided the closure of the land treatment unit (LTU) which was used to treat OU4 soil. Following LTU closure and site redevelopment, the site was partially removed from the Minnesota Environmental Response and Liability Act (MERLA) Permanent List of Priorities (PLP) and from the federal Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA) National Priorities List (NPL). 3 1.1.2.1 Operable Unit 5 The West Area, which remains on the MPCA’s PLP and the USEPA’s NPL, is now designated as Operable Unit 5 (OU5). Also included in OU5 are two Joslyn-owned residential lots located immediately south of the West Area (the Southern Lots). Several environmental investigations have been conducted in OU5 to determine the magnitude and extent of PAH, PCP, and TCDD-TEQ 1 soil contamination. In the West Area, soil sampling has been conducted in 1981, 1986, 1997, 1998, 1999, as summarized in the Sampling and Analysis Plan – Supplemental West Area Characterization (Barr, 2000) and 2003, as summarized in the West Area Remedial Investigation Report (Barr, 2003). Additional soil sampling was conducted in the West Area in 2014 and 2015 as part of pre-design waste characterization and geotechnical assessment. An investigation of the Southern Lots for dioxin/furans in surficial soils was conducted in 2005 (Barr, 2005). The data from the Southern Lots were incorporated with 2003 investigation data for the West Area and then used to assess remedial action alternatives (Barr, 2017). This permit application applies to the proposed remedial action alternative for OU5 that will be implemented under the May 1985 Consent Order between Joslyn and the MPCA. The selected remedy, described in detail in Section 3.0, will be chosen in accordance with CERCLA (USEPA, 1980), as amended by Superfund Amendments and Reauthorization Act of 1986 (USEPA, 1986), and, to the extent practicable, the National Oil and Hazardous Substances Pollution Contingency Plan, more commonly known as the National Contingency Plan (NCP) [USEPA, 1994]. MPCA has recently published the Proposed Plan for OU5. MPCA will gather public comments and input on the proposed remedial action, then will select and document the OU5 remedial action in a Record of Decision (ROD). The submittal of this permit application during the public comment period is intended to provide potential commenters with a complete understanding of the proposed project. This permit application has been prepared in accordance with the following rules and regulations: • Joint Application Form for Activities Affecting Water Resources in Minnesota (Joint Application Form), which covers these requirements: o Minnesota Wetland Conservation Act (WCA) , as administered by Shingle Creek Watershed Management Commission (SCWMC) o Minnesota Department of Natural Resources (MDNR) Public Waters Work Permit Program o United States Army Corps of Engineers (USACE) Department of the Army Permit • SCWMC Rules and Standards, April 2013 1 The term “TCDD TEQ” means the total toxicity of individual polychlorinated dibenzo-p-dioxins (CDDs) and polychlorinated dibenzofurans (CDFs) or mixtures of CDDs and CDFs expressed as an equivalent of 2,3,7,8-tetrachlorodibenzo-p-dioxin or 2,3,7,8-TCDD after the World Health Organization, 1998. 4 • City of Brooklyn Center Ordinances (including floodplain and land disturbance) The USACE regulates the placement of fill material into wetlands that are located adjacent to, or hydraulically connected to, interstate or navigable waters under the authority of Section 404 of the Clean Water Act. This permit application is being submitted to request authorization of the proposed work using the Joint Application Form. However, though activities undertaken on a CERCLA site by authority of CERCLA as approved or required by EPA are not required to obtain permits under Section 404 of the Clean Water Act. The filling, excavation, and draining of wetlands is also regulated by the WCA, which is administered by the SCWMC. Stormwater and floodplain impacts are also regulated by the SCWMC. The Joint Application Form can be found in Appendix A and the SCWMC Project Review Application Form can be found in Appendix B. Work within Public Waters is regulated by the MDNR. The MDNR Work in Public Waters Permit application (MPARS) was completed online and a copy is attached to the Joint Application Form. 5 2.0 Existing Conditions As indicated in Section 1.0, OU5 consists of the West Area (an undeveloped 11.1-acre parcel of land located adjacent to the eastern shore of Middle Twin Lake) and the Southern Lots (two undeveloped parcels totaling 0.6 acres immediately south of the West Area that are owned by Joslyn) [Figure 2]. This section describes the existing conditions of each area in greater detail. 2.1 West Area 2.1.1 Existing Land Use The West Area is comprised of wetlands and wooded upland. It is identified as remaining undeveloped open space in the City of Brooklyn Center’s Comprehensive Plan for 2020 (Comprehensive Plan), but is currently zoned industrial (City of Brooklyn Center, 2000). Because much of the West Area falls below the 100-year flood elevation of Middle Twin Lake, as discussed in Section 2.1.3, it is not expected that it could ever reasonably be developed for industrial purposes. Joslyn currently owns the West Area and maintains it as open space within a perimeter fence that makes the West Area inaccessible to the general public. Joslyn has stated that their intention for the West Area is “to preserve it in perpetuity as fenced open space, inaccessible to the general public” (Joslyn, 2004). The MPCA has determined that the reasonably anticipated land use for the West Area is industrial with the possibility that the West Area will remain as open space in the future (MPCA, 2004b). Soils in the West Area consist of fill, as well as native lacustrine fine sands, silts and clays and peat in the wetland portions. Historic aerial photographs show that a pond was present in the southern portion of the West Area prior to 1950 (designated Pond C). A shallow constructed waterway, sometimes referred to as the “former ice chute,” once existed across the north portion of the West Area. In the mid-1960s, an embankment for a railroad spur was placed from east to west across the central portion of the West Area, splitting the West Area wetland into a northern and a southern portion. In 1999, it was recommended by the MDNR that the former spur be restored to an elevation that would more clearly define the boundary between wetland jurisdictions within the West Area. The southern portion of the wetland (south of the former rail spur) is under the jurisdiction of the USACE and the WCA through the SCWMC, while the northern portion of the wetland (north of the former rail spur) is under the jurisdiction of the MDNR and the USACE. 2.1.1.1 Sub-Areas As part of the environmental sampling conducted in 1999, the West Area was organized into a number of sub-areas (Figure 3). The delineation of each sub-area was based on topography, history of fill placement as observed in historic aerial photographs, and vegetation patterns. Sub-areas WA-1, WA-2, and WA-3 are generally upland areas on the eastern edge of the West Area adjacent to the former wood treating areas on the Site. Historic fill placement was observed in these three sub-areas during review of Site aerial photographs. Sub-areas WA-4 and WA-5 are located on the western edge of the West Area adjacent to Middle Twin Lake; WA-4 consists primarily of forested upland, while WA-5 consists entirely of wetland. 6 Sub-area WA-6 is located in the south-central portion of the West Area, and represents the approximate former location of a disposal pond at the facility known as Pond C. Pond C was used for the disposal of boiler blowdown water from sometime prior to 1944 until approximately 1950. WA-6 was further subdivided into WA-6S, WA-6MID and WA-6N based on historic site features, including the former rail spur which had intersected Pond C. WA-6 consists almost entirely of shallow marsh, wet meadow, and floodplain forest wetland. Sub-area WA-7 is a shallow marsh located in the north-central portion of the West Area. Sub-area WA-8 is defined as the east-west former rail spur located in the central portion of the West Area. 2.1.2 Existing Stormwater Management Surface water runoff from most of the Joslyn Site has historically been conveyed to the West Area for retention and infiltration. With redevelopment of the Site, approximately 48.7 acres, which includes the original 36-acre Joslyn Site as well as a portion of the surrounding area, now drain to the West Area (Figure 4). Existing stormwater infrastructure for the Site services the current development (three buildings, associated parking lots, and Azelia Avenue between Lake Breeze Avenue and the railroad tracks). The onsite buildings are known as Buildings 1, 2, and 3, with Building 1 located nearest Middle Twin Lake, Building 2 in the middle of the development just east of Azelia Avenue, and Building 3 furthest east and nearest Highway 100. As shown on Figure 4, three stormwater ponds currently serve the Site: • Azelia Avenue Pond: This wet sedimentation pond is the largest of the three ponds and is located east of Building 1. This facility collects stormwater runoff from the development east of Azelia Avenue. • Building 1A Pond: This wet sedimentation pond is located north of Building 1 and collects stormwater runoff from the runoff from the Building 1 parking lots. • Building 1B Pond: This wet sedimentation pond is located west of Building 1 and collects stormwater runoff from the Building 1 roof. The three existing stormwater ponds discharge into the West Area at three different locations (Figure 4). Building 1A Pond discharges through a 12-inch pipe into the northern portion of the West Area directly west of its location, while Building 1B Pond discharges through a 24-inch pipe into the West Area immediately south of the former rail spur. The third inflow into the West Area is from the Azelia Avenue Pond, which was designed to discharge to Building 1A Pond until the Azelia Avenue Pond water level rises above its overflow elevation, in which case flow is then routed to the southern portion of the West Area via twin 22-inch by 36-inch arch pipes and through the existing swale located south of Building 1 (the “south swale”). The conveyance of stormwater through the West Area is generally from south to north. Runoff conveyed to the southern portion of the West Area will accumulate and then either evaporate or infiltrate except during large storm events when flow may overtop the railway spur (currently at 852.2 feet MSL) and 7 discharge into the northern portion of the West Area. Stormwater runoff conveyed to the northern portion of the West Area has two potential pathways into Middle Twin Lake: the former ice chute located along the western boundary (851.5 feet MSL) and through emergent vegetation located at the northwestern boundary of the West Area (851.5 feet MSL). These outlet locations are shown on Figure 4. Further details regarding existing stormwater management for OU5 can be found in Section 4.0. 2.1.3 Existing Floodplain Most of the ground surface within the West Area falls below the elevation of the 100-year flood elevation of Middle Twin Lake. During periods of high snowmelt runoff and/or high sustained precipitation, the water level of Middle Twin Lake remains elevated for long periods of time (sometimes weeks or months). The 100-year flood elevation, ordinary high water level (OHWL), and normal water level (NWL) for Middle Twin Lake are 856.0, 853.1, and 851.5 feet MSL, respectively. The 100-year flood elevation was obtained from the Federal Emergency Management Agency (FEMA) Flood Insurance Rate Map (FIRM) [FEMA, 2004] and checked for agreement with the unpublished FEMA Digital Flood Insurance Rate Map (DFIRM). The OHWL was obtained from the MDNR Lake Finder records. The NWL was obtained from SCWMC’s technical advisor, Wenck Associates (Wenck, 2009). The limits of the OHWL and the 100-year flood level of Middle Twin Lake are shown on Figure 5. 2.2 Southern Lots 2.2.1 Existing Land Use Each of the Joslyn-owned Southern Lots are approximately 0.3 acres in size and both are currently zoned for residential use. Joslyn anticipates continued ownership of these two parcels with the use of institutional controls so that they will remain undeveloped in perpetuity (Barr, 2005). Soils in the Southern Lots consist of fill, as well as native lacustrine fine sands, silts, clays, and peat. The lots are relatively well vegetated, with trees and shrubs covering the majority of both parcels. 2.2.2 Existing Floodplain The 100-year floodplain of the Middle Twin Lake is connected to the Southern Lots via the West Area. Over one-half of the Southern Lots fall within the 100-year floodplain of Middle Twin Lake and roughly one-half of the Southern Lots falls below the OHWL (Figure 5). The 100-year flood elevation, ordinary high water level (OHWL), and normal water level (NWL) for Middle Twin Lake are 856.0, 853.1, and 851.5 feet MSL, respectively. 2.2.3 Existing Stormwater Management The Southern Lots have an approximate total drainage area of four acres. Surface runoff from the surrounding area, which includes residential lots and streets, is routed into the low-lying (wetland) portion of the Southern Lots. Once storage within this area is filled, overland flow from the Southern Lots flows into the southern portion of the West Area (Figure 4). Further details regarding existing stormwater management for the Southern Lots can be found in Section 4.0. 8 3.0 Remediation and Mitigation Work Per the 1985 MPCA Consent Order, remediation is required within OU5 to address the potential human health and ecological risks associated with the contaminated soils. This section describes the remediation objectives, the remediation alternatives considered by Joslyn and the MPCA, and the proposed scope and schedule for the remediation alternative selected by the MPCA. 3.1 Remediation Objectives The overall cleanup strategy for the OU5 remedy is to eliminate the potential exposure pathways for both human and ecological receptors by addressing contaminated soils. Direct contact with soils is limited to soils that are considered accessible to these receptors. For the West Area, “accessible” for human receptors was defined as the upper three (3) feet of the final grade (MPCA, 1998a), with subsequent discussion with the MPCA resulting in acceptance of an accessible zone of two (2) feet below grade with an underlying geotextile. For residential land use scenarios, including the Southern Lots, the MPCA’s Risk- Based Site Evaluation Manual defines human accessible contamination as, “soil contamination generally located less than four (4) feet below the surface where the surface is not completely covered by an impervious (e.g., pavement) or permanent structure” (MPCA, 1998b). Ecological risk was evaluated by assessing the presence of non-conforming soils within a layer of soil called the bioactive zone (BAZ). In June 2005, MPCA cited experience at other contaminated sites that led them to conclude that the BAZ in the West Area should be either 2 feet or 3 feet. MPCA indicated that a 2-foot thickness was acceptable in areas where the underlying contamination did not drastically exceed ten times the preliminary remediation goal (PRG). The MPCA also requested the use of an isolation zone (IZ) to further protect the remedy and the BAZ in wetland areas. The IZ will consist of 6 inches of clean soil backfilled prior to placement of a non-woven geotextile fabric that demarcates the boundary of the remedial excavations. A comparison of existing soil quality data to the human health and ecological screening values and consideration of BAZ requirements for each of the sub-areas within OU5 resulted in the proposal of a remedial action that establishes sufficient protection through a combination of covering and excavation. A more detailed description of the remedial action objectives, including a listing of the BAZ, IZ, and geotextile requirements by OU5 sub-area can be found in the July 2013 Focused Feasibility Study (FFS) [Barr, 2017]. 3.2 Remediation Alternatives The FFS details eight (8) remedial alternatives developed and evaluated with respect to the statutory balancing criteria in Section 121 of CERCLA and in Section 300.430 of the NCP. The remedial alternatives were evaluated using the following nine criteria: • Overall protection of human health and the environment 9 • Compliance with Applicable and/or Relevant and Appropriate Federal and State public health or environmental requirements (ARARs) • Long-term effectiveness and permanence • Reduction of toxicity, mobility, or volume of hazardous substances • Short-term effectiveness • Implementability • Cost-effectiveness • Acceptance by EPA • Acceptance by Community The NCP categorizes the nine criteria into three groups: 1. Threshold Criteria—overall protection of human health and the environment and compliance with ARARs (or invoking a waiver) are threshold criteria that must be satisfied in order for an alternative to be eligible for selection; 2. Primary Balancing Criteria—long-term effectiveness and permanence; reduction of toxicity, mobility, or volume; short-term effectiveness; implementability, and cost are primary balancing factors used to weigh major trade-offs among alternatives; and 3. Modifying Criteria—state and community acceptances are modifying criteria that are formally taken into account after public comment is received on the proposed plan and incorporated into the Record of Decision (ROD). Two additional criteria were also used to evaluate the remedial alternatives: • Principal threat waste considerations • Floodplain and wetland mitigation The eight alternatives (and their potential wetland and floodplain impacts) are described briefly in Section 7.5. In the FFS, Joslyn recommended Alternative 8b as the best balance of criteria, including protection of human health and the environment, minimizing wetland and floodplain impacts, and cost. MPCA has prepared and issued a Proposed Plan for the project based upon Alternative 8b. This Proposed Plan is currently undergoing a public comment period. Following the public comment period, MPCA will review comments received and the evaluation criteria and write a ROD selecting a final remedy. This permit application will be amended if the selected remedy differs from Alternative 8B. 3.3 Remediation and Mitigation Work Plan The proposed OU5 remedy consists of the excavation of contaminated soil, followed by consolidation of a portion of the excavated soils within the West Area itself and disposal of the remaining portion of the 10 excavated soils in a landfill. The onsite consolidation area will be constructed over contaminated soil that remains in place in the southern part of the West Area. In an attempt to minimize wetland and floodplain impacts, a portion of the OU5 soils will be disposed offsite in a Subtitle D Landfill. Of the entire OU5 area (11.7 acres), approximately 8.3 acres require response action. Of those 8.3 acres, approximately 3.5 acres will be excavated and consolidated (with 1.3 acres of contaminated soil remaining in place under the consolidation area) and 4.8 acres will be disposed in a Subtitle D Landfill. The onsite consolidation area will be constructed as indicated in the construction drawings (Appendix C) and specifications (Appendix D). This remedy establishes sufficient protection for both human health and the environment and is compatible with the remedies for the other operable units at the Joslyn Site that are currently ongoing or have been completed (Section 1.1.1.1). The scope of work for the OU5 remediation is anticipated to include the following tasks: • Temporary erosion and sediment control • Removal and disposal of vegetation including brush and trees • Temporary and permanent stormwater management • Access road construction • Excavation of contaminated soils and placement of selected soils within the consolidation area • Excavation of contaminated soils and transportation and disposal of selected excavated soil at an off-site Subtitle D landfill • Placement of non-woven geotextile fabric • Placement of 1.5 feet of clean cover soil at consolidation area • Placement of 0.5 feet of topsoil at consolidation area • Backfill of excavated areas with clean fill to original grade • Floodplain and wetland mitigation • Site restoration – planting and establishing vegetation • Post-construction maintenance and monitoring Detailed information regarding the remedial work can be found in the following sections. 3.3.1 Erosion and Sediment Control Rigorous erosion and sediment control measures will be employed for OU5 to prevent migration of contaminated soil outside of defined work areas, as described in Section 5.0 and as shown in the Construction Drawings (Appendix C), during construction and final stabilization periods. 11 3.3.2 Clearing and Grubbing Existing trees in the West Area and Southern Lots will be cleared in the excavation areas as required for equipment access. To the extent practicable, trees will be chipped and spread onsite or used in soil amendments. 3.3.3 Stormwater Management The temporary and permanent stormwater management plan for OU5 is detailed in Section 4.0 and is shown in the Construction Drawings (Appendix C). 3.3.4 Access Roads Access roads will be required to safely perform the excavation within OU5 with minimal impact to the environment and construction equipment. It is anticipated that the entrance to the OU5 project area will be from the existing Building 1 fire road directly adjacent to the existing rail spur. Access roads will be constructed within the OU5 project area by the contractor as necessary to complete the work. 3.3.5 Consolidation of Soils into Onsite Consolidation Area Consolidation and cover will be done in a manner that addresses environmental concerns while ensuring long-term stability of the consolidation area. The consolidation area will feature a soil cover that will consist of a geotextile fabric overlaid with 1.5 feet of clean cover soil and 0.5 feet of clean topsoil. The purpose of the geotextile is as follows: (1) to meet the requirement of a 2-foot accessible zone as described in Section 3.1, (2) to provide a demarcation between the cover soils and the underlying contaminated soils, (3) to reduce the potential for contaminant transport upward into the clean cover, and (4) to help reduce differential settlement. The consolidation area was designed to reduce floodplain, wetland, and stormwater impacts by raising the height of the pile to accommodate consolidated soils rather than spreading the pile over a larger area. The pile will have 4 (horizontal):1 (vertical) side slopes for improved maintenance and stability. 3.3.6 Excavation and Backfill of Contaminated Areas The OU5 sub-areas will be excavated and backfilled as shown in the construction drawings (Appendix C). The areas will be excavated to the depths required to meet the objectives described in Section 3.1. After excavation, geotextile fabric will either be placed over 6-inches of backfill if an additional IZ is required from the excavation bottom (typically wetland areas) or simply placed at the excavation bottom if no separate IZ is needed (typically upland areas). 3.3.7 Floodplain Mitigation Floodplain mitigation for OU5 is detailed in Section 6.0. 3.3.8 Wetland Mitigation Wetland mitigation for OU5 is detailed in Section 7.0. 12 3.3.9 Site Restoration Site restoration for OU5 is detailed in Section 5.5. 3.3.10 Inspection and Maintenance Long-term post-construction site work will include inspection and maintenance of the stormwater management system, surface soil erosion, wetland vegetation, perimeter fence, and the consolidation area cover vegetation. Institutional controls will be put in place to restrict future land use as necessary. 3.4 Remediation Schedule It is currently anticipated that remediation for OU5 will commence in the fall of 2017 and be completed in 2018. 13 4.0 Stormwater Management The proposed OU5 remedy will require temporary changes in stormwater management during implementation of the project, and will result in permanent changes in stormwater management for the site after the proposed work is complete. As described and presented in this section, the proposed changes have been incorporated into both stormwater management modeling and design and hydrologic and hydraulic modeling to estimate their effects on Middle Twin Lake. Model output can be found in Appendix E. 4.1 Stormwater Design The stormwater design elements for OU5 include temporary and permanent stormwater management measures, as described below and shown in the construction drawings (Appendix C). 4.1.1 Temporary Stormwater Management The temporary stormwater management system has been designed to accommodate construction activities while protecting the valuable water resources within and adjacent to the Joslyn site. All components of the temporary stormwater management system are addressed in the following sections. South Swale Diversion and Culvert A temporary berm will be created to divert runoff from the south swale and the Southern Lots to Middle Twin Lake via a temporary 24-inch corrugated metal culvert (CMP). The temporary berm will, in essence, extend the south swale to the culvert inlet and have a top elevation of 855.0 feet MSL. The outlet of this pipe will be placed at the normal water level (NWL) of the lake (851.5 feet MSL), and a check valve will be installed to prevent backflow from the lake during periods of high water. 4.1.1.1 Sheet Piling As indicated in Section 5.3.1, sheet piling will be installed along the northern perimeters of sub-areas WA-1, WA-5 and WA-7 for the purposes of stormwater runoff diversion and sediment control. The sheet piling will be driven to final grade upon completion of construction. 4.1.1.2 Building 1B Pond Outlet Removal The Building 1B Pond outlet will be plugged and pumped from the existing manhole as needed to an area not under construction either north of the rail spur, south of the rail spur, or to the diverted south swale. This is necessary to minimize stormwater inputs to the primary excavation and backfill areas. 4.1.2 Permanent Stormwater Management The permanent stormwater management system has been designed to retain and attenuate stormwater discharges while improving the corresponding water quality in accordance with the rules and standards of the SCWMC and the NPDES Permit. No new impervious areas are added to the site as a result of this project (i.e., there is no development of the West Area). The permanent stormwater management system incorporates modifications to the existing conveyance system to limit peak discharge rates and runoff 14 volumes, and enhance water quality. The components of the permanent stormwater management system modified as a result of this project are detailed in the following sections. 4.1.2.1 Sewer Piping New storm sewer will be installed to replace the Building 1B Pond outlet that will be removed during construction. 4.1.3 Permanent Stormwater Treatment BMPs Two permanent stormwater treatment BMPs will be constructed to treat stormwater prior to discharge to Middle Twin Lake, including: Former Ice Chute Area The elevation of the ground surface in the portion of sub-area WA-5 associated with the former ice chute will be increased to the adjacent grade to eliminate the direct connection between the West Area’s north wetland to Middle Twin Lake. Raising the elevation of the former ice chute area will also increase the residence time in the northern wetland, providing increased treatment of stormwater runoff post- construction. Former Rail Spur The ground surface elevation of the former rail spur will be raised to above the Ordinary High Water Level (OHWL) as recommended by the MDNR to clarify the landward extent of regulatory jurisdiction of Middle Twin Lake (MDNR, 1999). This, in combination with the proposed floodplain mitigation within sub-area WA-4, will effectively increase storage over the existing condition allowing for increased residence time during normal conditions prior to discharging into the north wetland. Wetlands are effective for water quality enhancement because they filter runoff allowing suspended sediments to settle and allow for biological uptake of nutrients in addition to other chemical processes. 4.2 Hydrologic and Hydraulic Analysis Hydrologic and hydraulic modeling of existing and proposed conditions was performed to confirm the effectiveness of the proposed stormwater management system with respect to rate control. Based on the Rules and Standards of SCWMC, discharge rates need to be maintained or reduced between existing and proposed conditions. No impervious surfaces, which would require the implementation of infiltration BMPs, are present within West Area. Therefore, infiltration was not explicitly modeled. Modeling methodology, inputs and results are detailed in the following sections. 4.2.1 Modeling Methodology Hydrologic and hydraulic modeling for the OU5 stormwater management design was completed using HydroCAD version 10.00-15, a computer stormwater modeling program based on the United States Department of Agriculture’s (USDA) Technical Release 20 (TR-20) and Technical Release 55 (TR-55) hydraulic programs. 15 4.2.2 Model Inputs The inputs for the HydroCAD modeling include rainfall, land use, time of concentration, and hydraulic features including storage areas/ponds, pipes, outlet structures, channels, and overflow berms. The assumptions for these parameters are as follows: Rainfall Rainfall depths for the 24-hr storm events are from the NOAA Atlas 14 Volume 8 (NOAA, 2013). The NRCS MSE 3 24-hour rainfall distribution was used in the modeling. Table 1 SCWMC Rainfall Depths Return Frequency NOAA Atlas 14 Volume 8, Version 2 Point Precipitation Estimates (inches)1 24- hour 12- hour 6-hour 3-hour 2-hour 1-hour 30-min 15-min 2-year 2.87 2.52 2.20 1.89 1.71 1.39 1.07 0.75 10-year 4.28 3.91 3.43 2.92 2.62 2.11 1.60 1.11 100-year 7.40 6.94 6.24 5.20 4.50 3.51 2.52 1.75 1Point precipitation frequency estimates were obtained for Brooklyn Center, MN (Coordinates: 45.0439, -93.3374, Elevation: 861 feet). Land Use Land uses for runoff determination consisted of the following three main cover types and associated Curve Number (CN) values: • Open water (CN=100) • Impervious area (CN=98) • Pervious grass cover in good condition assumed to have Hydrologic Group B soils (CN=61) • Wooded areas in good condition assumed to have Hydrologic Group B soils (CN=55) • Zero infiltration rates were assumed for the north and south wetland areas The existing and proposed drainage areas, labeled according to HydroCAD model node for reference, are shown in Figures 5 and 6, respectively. Time of Concentration The time of concentration represents the time required for runoff to travel from the most hydrologically distant point of the watershed to the collection point. For each watershed, the time of concentration was estimated by summing the estimated travel time of each flow segment along each watersheds longest flow path. The TR-55 Chapter 3 method was used for calculating the time of concentration for each watershed. 16 Hydraulic Features The hydraulic features in the models include storage areas/ponds, channels, overflow berms, pipes, and outlet structures, In the existing conditions model, the stage storage curves of the storage areas/ponds, the channel geometry, and the geometry of the overflow berms were calculated from the topographic survey of the site. In the proposed conditions model, the geometries were adjusted to match the proposed design on the drawings. Pipes and outlet structure geometries were modeled based on information gathered during the topographic survey and from asbuilt drawings of the site features. 4.2.3 Modeling Results As indicated in Table 2 below, the results of the hydrologic and hydraulic modeling show that proposed peak runoff rates fall below existing conditions peak runoff rates for the 2-, 10-, and 100-year, 24-hour storm events. The overall reduced peak runoff rates result from the increased storage within the southern wetland, allowing for greater attenuation of peak flows within the wetland system. The results of the analysis are summarized in the table below. Table 2 Stormwater Modeling Results – Peak Runoff Rate Condition Peak Runoff Rate (cfs) 2-year 10-year 100-year Existing Conditions 10 32 122 Proposed Conditions 5 16 94 cfs – cubic feet per second Flood elevations were calculated for the 2-, 10-, and 100-year, 24-hour storm events. The hydraulic and hydrologic analysis only evaluated the area tributary to the project. It did not simulate the larger Middle Twin Lake watershed. The south wetland and southern lots are adjacent to public right-of-way and residential lots. The flood elevation analysis focused on this area to determine if the project might affect flood elevations for those properties. The results of the modeling for the south wetland and southern lots (model element 2P) are summarized in Table 3. Table 3 Stormwater Modeling Results – South Wetland Flood Water Elevations Condition Flood Water Elevations 2-year 10-year 100-year* Existing Conditions 852.32 852.52 853.00 Proposed Conditions 852.92 853.26 853.70 * Flood elevations for the South Wetland during the 100-year event would be most likely be controlled by the 100-year water surface elevation in Middle Twin Lake, 856.0 msl. 17 The proposed condition flood elevations are higher than the existing condition flood elevations. The increase is caused by the raising the former rail spur to elevation 853.1. While flood elevations in the south wetland increase when evaluating the project area, flood levels for large events would be controlled by the water level in Middle Twin Lake, which has a 100-year flood elevation of 856.0. Due to the multiple, sometimes competing, regulations for the project, an evaluation of all consequences of raising the rail spur were considered. The consequences include: • Increase in localized flood elevations (as documented in this section), but well below the 100-year flood elevation for the Middle Twin Lake watershed • Increased phosphorous and total suspended solids retention (see section 4.3), in compliance with SCWMC regulations and the Twin and Ryan Lakes TMDL • Clarification of jurisdictional wetland between north (DNR) and south (WCA) wetlands (see Section 7.2 and Appendix H) It was determined that, through consideration of all the above factors, raising the former rail spur to the ordinary high water level (853.1) is the best option. Detailed model output including all hydrologic and hydraulic inputs and results can be found in Appendix E. 4.3 Water Quality Analysis Water quality modeling of existing and proposed conditions was performed to confirm the effectiveness of the proposed stormwater management system with respect to the removal of phosphorus and total suspended solids. Based on the Rules and Standards of SCWMC, the stormwater management system must remove 60 percent of total phosphorus and 85 percent of total suspended solids. The model was also used to compare the removal rates of the existing system to the proposed system. Modeling methodology, inputs and results are detailed in the following sections. 4.3.1 Modeling Methodology Water quality modeling was completed using P8 (Program for Predicting Polluting Particle Passage thru Pits, Puddles, and Ponds) Urban Catchment Model Version 3.5, created by William Walker, Jr., Ph.D, to simulate urban watershed BMP design and predict runoff quality based on the USEPA’s National Urban Runoff Program (NURP) study results (USEPA, 1983). 4.3.2 Model Inputs The inputs for the P8 modeling include rainfall, pollutant loading and land use. The assumptions for these parameters are as follows: Rainfall The model was run with daily precipitation from the years 1998 through 2007 from the Minneapolis/St. Paul Airport, with five passes through the storm file to purge the effects of the initial conditions. 18 Pollutant Loading The USEPA Nationwide Urban Runoff Program (NURP) 50th percentile particle file was used to estimate solids and total phosphorus loadings from the watershed area because it represents typical particle buildup and washoff for urban-type developments. Land Use The following inputs were used in defining the watersheds (Figures 5 and 6): • A pervious area curve number of 61 was used to be consistent with the pervious curve number used in the HydroCAD modeling. • A value of 0.02 inches was used for depression storage to simulate typical urban source areas. • The wetland south of the raised rail spur (south wetland) and north of the raised rail spur (north wetland) were modeled as detention basins with the permanent pool set at the proposed railroad spur elevation (853.1 feet MSL) and existing overflow elevation (851.5 feet MSL), respectively. Zero infiltration was assumed for either basin. • It is assumed that all impervious areas within the drainage are not swept. 4.3.3 Modeling Results As indicated in Table 4 below, the results of the water quality modeling analysis show that both existing and proposed conditions meet the rule-required removal efficiencies. The modeling also indicates that the BMPs that will be in place after remediation will remove as much or more total phosphorus and total suspended solids than the existing condition. As a result, less total phosphorus and total suspended solids are expected to be conveyed to Middle Twin Lake. The increased removal efficiency results from the increased storage and corresponding residence time within the south and north portions of the wetland obtained through the construction of the floodplain mitigation area and raised overflow elevations of the railroad spur embankment and ice chute area. In general, the wetlands within the West Area and Southern Lots enhance water quality treatment provided by the three existing wet sedimentation basins. The results of the analysis are summarized in the table below. Table 4 Water Quality Modeling Results Condition Retained (lbs/yr) Discharged (lbs/yr) Removal Rate (%) TSS TP TSS TP TSS TP Existing Conditions 16,602 36.5 1,208 21.1 93 63 Proposed Conditions 16,995 38.0 181 19.6 95 66 Rule Requirement -- -- -- -- 85 60 Detailed model output including all hydrologic inputs and results can be found in Appendix E. 19 4.4 TMDL Implementation Plan Compliance The chosen remedial alternative and stormwater management plan will need to comply with the November 2007 Twin and Ryan Lakes TMDL Implementation Plan (Wenck, 2007). The MPCA has listed North, Middle, and South Twin Lakes and Ryan Lake as impaired due to excess nutrients. Therefore, the focus of the TMDL implementation plan is to reduce annual total phosphorus loads to the lakes. The plan identifies the need for increased infiltration and retrofits to achieve the maximum possible total phosphorus load reduction. The conceptual stormwater management plan developed for this remediation project will achieve the intent of the TMDL Implementation Plan, because all stormwater runoff will be treated prior to discharge to the Middle Twin Lake. In particular the following BMPs will provide nutrient removal: • Building 1A Pond and Azelia Avenue Pond currently provide treatment as wet ponds and will continue to provide treatment after construction. • Building 1B Pond currently serves as a vegetated filter and will continue to provide treatment after construction. • Restoration of the wetland located within sub-area WA-6 and the Southern Lots, and expansion into sub-area WA-4 for the purposes of floodplain mitigation will further filter runoff from the south swale and the Southern Lots drainage area. • Restoration of the wetland in sub-area WA-7 will serve to enhance the water quality of runoff from the south wetland and both Building 1A and Building 1B Ponds. • The elimination of the direct connection between the West Area and Middle Twin Lake via the former ice chute area will prevent the north wetland from discharging in this location, increasing the residence time for runoff treatment within the wetland. • Raising the rail spur to the OHWL of 853.1 feet MSL in conjunction with maintaining a berm elevation of approximately 854 feet MSL along the west perimeter of the floodplain mitigation area will prevent direct discharge into Middle Twin Lake. Storage volume within the southern wetland will be increased, enhancing rate control and settling of nutrients. These BMPs will aim to protect Middle Twin Lake by providing improved physical and biological processes for total phosphorus removal, including sedimentation, filtration, infiltration, and vegetative uptake. 4.5 Maintenance Per SCWMC rules, the stormwater BMPs will be maintained in perpetuity to ensure that they continue to function as originally designed. 20 5.0 Erosion and Sediment Control This section describes the erosion and sediment control methods for the OU5 remediation work. Per SCWMC rules, erosion and sediment control methods will be in compliance with the MPCA’s NPDES Construction General Permit (General Permit) [MPCA, 2013] and consistent with best management practices (BMPs) outlined in the MPCA’s “Protecting Water Quality in Urban Areas” manual (MPCA, 2000) and in the Minnesota Stormwater Manual (MPCA, 2017). Erosion and sediment controls will be installed prior to the start of land disturbance and will not be removed until project completion. The lake adjacent to the project, Middle Twin Lake (Lake ID# 27-0042-02), is identified as impaired for nutrient/eutrophication biological indicators under Section 303(d) of the Clean Water Act. The following erosion control and sediment control measures will be taken for OU5 in accordance with applicable regulations for impaired waters and as necessary to prevent migration of onsite soils. The construction sequencing incorporating these measures can be found in Section 8.0. Details of the erosion and sediment control plan can be found in construction plans and specifications found in Appendix C and Appendix D, respectively. 5.1 Construction Schedule Excavation work for OU5 is anticipated to occur during the late fall and winter months to reduce the potential for significant stormwater runoff events and/or fugitive dust and odor emissions. 5.2 Dewatering To facilitate excavation of the target soils, dewatering of the existing wetlands will be conducted in compliance with the General Permit guidelines. Dewatering water will be treated in the West Area for sediment removal (e.g. bag filters) prior to routing to the existing Joslyn Site groundwater pump-out system for pre-treatment prior to discharge to the sanitary sewer system. 5.3 Temporary Erosion and Sediment Control These measures, as indicated in the construction drawings (Appendix C) and specifications (Appendix D), will include: 5.3.1 Sheet Piling Sheet piling will be installed along a portion of the perimeters of sub-areas WA-1, WA-5, and WA-7 for flow discharge and sediment control. The sheet piling will prevent piped discharges from Building 1A Pond from reaching sub-areas WA-1 and WA-7 during construction and will also prevent sediment-laden runoff within WA-1 and WA-7 from reaching Middle Twin Lake by blocking off the existing wetland overflow location. It is necessary to extend the temporary sheet pile along the western perimeter of WA-5 to tie into higher ground. Once construction is completed and the wetland area is stabilized, the sheet piling will be driven into the ground to the existing grade. 21 5.3.2 Construction Fence High visibility construction fence will be used to delineate areas not to be disturbed for the OU5 remediation work. 5.3.3 Silt Fence Silt fence will be used on the downslopes of the site to prevent the migration of sediment onto the properties adjacent to the Southern Lots or other undisturbed wetland areas. Silt fence will also be used around any onsite temporary soil stockpiles. 5.3.4 Flotation Silt Curtain Flotation silt curtain will be used as necessary within Middle Twin Lake during open water periods adjacent to West Area sub-areas WA-5 (former ice chute) and WA-8 (former rail spur) to prevent sediment migration during the excavation of these areas adjacent areas. Installation of flotation silt curtain will be required within Middle Twin Lake at the outlet of the temporary culvert located within sub-area WA-4 at the south end of the project area. 5.3.5 Rock Construction Entrance A rock construction entrance will be used on the south side of Building 1 at the west end of the parking lot where construction equipment will enter and exit the site to prevent the migration of sediment. 5.3.6 Equipment Decontamination Area An equipment decontamination area for construction equipment will be located within the project area, adjacent to the Rock Construction Entrance. The decontamination area will contain all tracked soil and wash water for on- site treatment. 5.3.7 Street Sweeping The parking lot where construction equipment will enter and exit for the OU5 remediation will be swept as necessary to remove tracked sediment. 5.3.8 Grade Breaks Per General Permit requirements, no unbroken slopes lengths greater than 75 feet for slopes with a grade of 3 (horizontal)):1 (vertical) or steeper will be allowed during construction to minimize rill and gully formation. 5.3.9 Stabilization Per NPDES Permit requirements, all exposed soil areas will be stabilized within 7 days after the construction activity has temporarily or permanently ceased. Stabilization for soil areas will be achieved through mulching of exposed areas. For the swale diverting water to Middle Twin Lake, stabilization of the temporary swale created on the outside of the sheet pile within WA-1 and WA-7 will be achieved through installation of erosion control 22 blanket. Within 200 feet of Middle Twin Lake, stabilization of the excavated and backfilled swale will occur within 24 hours. 5.3.10 Rock Check Dams Rock check dams will be used north of the sheet piling as shown on Drawing C-3 to limit flow velocity and promote settling of sediment. 5.4 Permanent Erosion and Sediment Control Permanent erosion control measures will be left in place after remediation of OU5 has been completed. These measures, as shown in the Construction Drawings (Appendix C), will include: 5.4.1 Riprap Riprap and filter will be installed at the outlets of existing and proposed stormwater pipes following pipe installation. 5.5 Site Restoration The 6-foot-high steel mesh perimeter fence that has been in place around the West Area since 2000 will be removed to facilitate the work and then replaced to reduce the potential for future trespassing or uncontrolled access to the project area. The onsite consolidation area and the excavated and backfilled areas will be seeded and/or planted upon completion of the remediation. The seeded area will be mulched and anchored, as shown on Drawing C-7. Trees will be planted within the disturbed areas as shown on Drawing C-8 to provide screening for adjacent property owners. The temporary culvert and diversion berm located at the outlet of the south swale will both be removed. 5.6 Inspections and Maintenance Inspections and maintenance of erosion and sediment control measures will be in accordance with SCWMC guidelines and the General Permit. The following inspection and maintenance measures will be taken for the project: 5.6.1 Frequency The frequency of inspections of temporary erosion and sediment control measures will occur in accordance with SCWMC guidelines and the General Permit until permanent vegetative cover is established and erosion and sediment controls have been removed (Section 5.7). In general, inspections shall be conducted daily during construction and weekly thereafter. Additionally, inspections shall be conducted within 24 hours of a rain event of 0.5 inch or more. 5.6.2 Recording Records of inspections and maintenance will be kept per the General Permit requirements. 23 5.6.3 Maintenance Measures The following maintenance measures will be taken to ensure the integrity and effectiveness of the erosion and sediment controls for the project: 5.6.3.1 Silt Fence Silt fence will be repaired, replaced or supplemented within 24 hours of discovery when it becomes nonfunctional or the sediment reaches 1/3 of the height of the fence, or as soon as field conditions allow access. 5.6.3.2 Construction Vehicle Exit Locations Sediment tracked offsite onto paved surfaces near construction vehicle exit locations will be removed within 24 hours of discovery. 5.6.3.3 Surface Water Conveyance Systems Maintenance of surface water conveyance systems, including sediment deposition removal and erosion repairs, will be completed within 7 days of discovery, or as soon as field conditions allow access. 5.7 Removal Temporary erosion and sediment control measures will be removed after a minimum 70% density of a uniform perennial vegetative cover has been established for the project area. 24 6.0 Floodplain Management OU5 floodplain management includes the actions that will be taken to create compensatory storage for fill placed within the 100-year floodplain as part of the OU5 remediation. Compensatory storage will be provided on site within sub-area WA-4 of the West Area and within the Southern Lots. The existing and proposed OHWL and 100-year floodplain elevations within the OU5 parcels are shown in Figures 5 and 6, respectively. Further detail regarding the proposed floodplain alteration and compensation is described in the following sections. 6.1 OU5 Floodplain Fill The construction of the onsite consolidation area, modified berm between the north and south wetland areas, and fill within the ice chute area will result in approximately 4,897 cubic yards of permanent fill within the 100-year floodplain. This includes all fill placed between the elevations 851.5 and 856.0 feet MSL. As indicated in Section 3.3.5, floodplain fill was minimized to the extent practicable by limiting the consolidation area and building the consolidation area upwards with a 4 (horizontal):1 (vertical) slope. 6.2 Compensatory Storage Compensatory storage will be provided by excavation of the knoll located within WA-4 and the Southern Lots above the NWL and below the 100-year floodplain elevation of Middle Twin Lake. While there is a floodplain fill volume of 4,897 cubic yards, a contingency percentage of approximately 13% has been planned to provide 5,554 cubic yards of compensatory storage during construction. The volume created by removal of material within each of the identified areas will therefore exceed the floodplain fill volume by approximately 660 cubic yards. Table 5 Fill and Compensatory Storage Volumes Location Fill Compensatory Storage Consolidation Pile 4,770 cu. yd. 0 Rail Spur 42 cu. yd. 0 Ice Chute 85 cu. yd. 0 Southern Lots 0 543 cu. yd. WA-4 Mitigation Area 0 5,011 cu. yd. Total 4,897 cu. yd. 5,554 cu. yd. 25 In concert with the stormwater management plan described in Section 4.0, a berm will be created along the western perimeter of the WA-4 floodplain mitigation area adjacent Middle Twin Lake, less than one foot above the OHWL. This berm will effectively contain stormwater runoff generated on site for storms up to the 100-year, 24-hour SCS Distributed Type II rainfall event. It should be noted, however, that Middle Twin Lake levels will, on occasion, exceed the berm. Appendix C (construction drawings) and Appendix D (specifications) should be referenced for details related to the floodplain mitigation. 26 7.0 Wetland Alteration 7.1 Wetland Delineation and Classification Methods The wetland boundaries were field delineated on August 30, 2007 within the West Area and May 20, 2010 in the Southern Lots. On October 23, 2012, the delineated wetland boundaries within the West Area and Southern Lots were evaluated again to update the delineation, and were approved on January 8, 2013. The delineations were established according to the Routine On-Site Determination Method specified in the U.S. Army Corps of Engineers Wetlands Delineation Manual (1987 Edition) and the August 2010 Midwest Regional Supplement. The wetland delineation report for the West Area was initially submitted to the MDNR; the Minnesota Board of Water & Soil Resources (BWSR); Wenck Associates, representing SCWMC; the USACE; the Hennepin Conservation District (HCD), which is now Hennepin County; the city of Brooklyn Center; and the MPCA on October 1, 2007. The wetland delineation was reviewed onsite by the technical evaluation panel (TEP) on October 17, 2007 and was approved with minor changes by the SCWMC. On May 20, 2010, the Southern Lots were evaluated for the presence of wetlands. After extending the evaluation area to include the Southern Lots, the wetland boundary was extended to the south into the Southern Lots property. Additional soil borings were conducted within the Southern Lots to document this extension of the wetland. The portion of the wetland boundary within the Southern Lots was initially delineated in 2010 after the initial TEP review and approval of the West Area delineation. On October 11, 2012 and October 18, 2012, pre-application meetings were held with the TEP to discuss the remediation plans and related wetland and floodplain permitting issues. At that time, the TEP agreed that a wetland delineation update could be conducted and reviewed in the fall of 2012 to bring the wetland delineation up-to-date. On October 23, 2012, Barr conducted a site wetland delineation update for the wetland located within the West Area and the Southern Lots (Appendix F). The delineated wetland boundaries were re-flagged and evaluated for accuracy. No changes were made to the previous wetland boundaries as a result of this site evaluation. During the October 23, 2012 wetland update evaluation, the wetland community types were more clearly defined to assist with accurate wetland permitting (Figure 7 of Appendix F). The updated wetland delineation report was submitted to the MDNR, BWSR, SCWMC, USACE, and HCD (now Hennepin County) on November 1, 2012 and is included in this wetland permit application as Appendix F. The wetland delineation report in Appendix F provides documentation of delineation methods. The National Wetland Inventory (NWI) map for the project area is provided in Figure 3 of Appendix F and the Hennepin County Soil Survey map is provided in Figure 4 of Appendix F. In addition, wetlands shown on the MDNR Public Waters Inventory (PWI) map for the surrounding area can be found on Figure 5 of Appendix F and watershed boundaries are shown on Figure 6 of Appendix F. Photographs taken during the August 30, 2007, May 20, 210, and October 23, 2012 site visits are located in Appendix F. The Notice of Decision approving the 2012 wetland delineation is provided in Appendix G. 27 7.2 Wetland Description Wetland 1 is a 9.01 acre, Type 3/1 (PEMC/FOA) shallow marsh within a floodplain forest fringe located in the West Area and the Southern Lots and extends to the west beyond the evaluation area into (L1UBH) Middle Twin Lake. The wetland also contains small portions of deep marsh (Type 4 PEMF) and wet meadow (Type 2 PEMB). Delineated wetland boundaries are shown in Figure 2 of Appendix F. The delineated wetland communities are provided in Figure 7 of Appendix F. This wetland is within the floodplain of Middle Twin Lake which is listed as a Public Water (27-42 P) by the MDNR (Figure 5 in Appendix F). Although this entire wetland is listed by the MDNR as a Public Water, previous work on this project resulted in the MDNR issuing a letter on August 20, 1999 indicating that the former rail spur was considered the landward extent of MDNR regulatory jurisdiction on Middle Twin Lake (Appendix H). The portion of Wetland 1 that is located south of the rail spur, therefore, was not considered to fall under MDNR jurisdiction. A full description of the vegetation, soils, and hydrology for the delineated wetland within the West Area and Southern Lots is provided in the wetland delineation report in Appendix F. 7.3 Historical Imagery Review Aerial imagery from 1937 through 2009 was reviewed with an overlay of the 2012 wetland delineation area (Appendix I). 7.3.1 West Area The former ice chute, described previously in Section 2.1.1, appears to have been active from 1937 through 1962. Historic aerial photographs show that a pond (Pond C) was present in the southern portion of Wetland 1, as described in Section 2.1.1.1. Inundation within this pond area is present in the 1945, 1951, 1956, and 1962 imagery. As indicated in Section 2.1.1, in the mid-1960s, an embankment for a railroad spur was placed from west to east across the central portion of the West Area intersecting the disposal pond. The spur was regraded to the current elevation in 1990. Inundation within Wetland 1 north of the railroad spur is present in the 1991, 1994, 1997, 2000, 2002, 2004, 2005, 2006, 2008, and 2009 aerial images. South of the railroad spur, inundation was observed in the 1997, 2006, and 2008 imagery. Historical fill placement was observed in the 1945, 1956, and 1971 aerial photographs along the eastern edge of the West Area adjacent to the former wood treating areas. In 1971, a ponded area, the former waste disposal Pond A, is present at the location of the current Building 1A Pond. This pond is not present in imagery from 1991 through 1997 during the OU4 LTU treatment described in Section 1.1.1.1. After site redevelopment, as described in Section 1.1.2, was completed in this area, Building 1A Pond was created in this area as shown in the 2000 imagery. 28 The 1991 imagery shows that operations at the Joslyn site had ceased and the land is leveled for the OU4 remediation. In the 2000 imagery, the light industrial building is present and Building 1A Pond was created. Azelia Avenue Pond, located east of Building 1, was created by 2002. 7.4 Agency Meetings 7.4.1 2007 TEP Meeting On October 17, 2007 a wetland delineation review and pre-application TEP meeting was conducted at the Joslyn site. Present at the meeting included Lynda Peterson (Minnesota Board of Soil and Water Resources), Wes Boll (Wenck Associates, representing SCWMC), Shelly Schwaninger (city of Brooklyn Center), Stacey Lijewski (Hennepin Conservation District, now Hennepin County), Steve Schoff (MPCA), John Hunt and Karen Wold (Barr). Joseph Yanta (USACE) and Julie Ekman (MDNR) were invited, but unable to attend the meeting. The purpose of the 2007 TEP meeting was to: 1. Seek approval of the wetland delineation. 2. Discuss the proposed West Area remediation alternatives explaining how remediation related excavation and/or filling will potentially impact wetlands and floodplain. 3. Discuss the jurisdictional status of the wetlands. 4. Discuss potential permitting requirements and the opportunity of wetland mitigation within the Proposed Mitigation Area. The wetland delineation was approved by the technical evaluation panel with minor changes as documented in the Notice of Wetland Conservation Act Decision Dated October 29, 2007 (Appendix G). Though the MDNR representative and the USACE representative were not present at the meeting, e-mail correspondence in October 2007 indicated that the USACE has federal jurisdiction and the MDNR has state jurisdiction for Twin Lake within the ordinary high water elevation of 853.1 feet MSL. The 1999 letter from the MDNR (Appendix H) indicates that the MDNR jurisdiction historically ends at the location of the railroad spur. Therefore the state regulation for the area south of the railroad spur would be under WCA jurisdiction. In conjunction with the field review, discussion was provided indicating the challenges involved in avoiding and minimizing wetland impacts, while meeting the goals and compliance issues regarding the proposed remediation project. It was pointed out that there are limited onsite mitigation opportunities because of existing land use. 7.4.2 2012 TEP Meetings On October 11, 2012 and October 18, 2012, pre-application TEP meetings were held to discuss the current wetland remediation plans and related wetland and floodplain permitting issues. Present at the meetings included Lynda Peterson (BWSR), Wes Boll and Diane Spector (Wenck Associates, representing SCWMC), Joe Yanta, Melissa Jenny, and Katherine Swanson (USACE), Kate Drewry (MDNR), Steve Lillehaug (City of 29 Brooklyn Center), Steve Schoff (MPCA), Leah Evison (USEPA), John Hunt, Sara Ramsden, Mark Jacobson, Troy Erickson, Alec Danielson, and Karen Wold (Barr). Stacey Lijewski with Hennepin Conservation District (now Hennepin County) was invited, but unable to attend the meetings. In addition to discussion regarding approval of the updated wetland delineation, the following topics were discussed at the 2012 TEP meetings: • A summary of the site history and description of the response action planning process was provided highlighting that the likely remediation remedy selected by the MPCA would require both floodplain and wetland mitigation. • Agency wetland jurisdiction and wetland replacement and mitigation requirements were discussed. • The USACE indicated that they would look into whether a General Permit or Individual Permit would apply. Follow up communication from Melissa Jenny indicated at the time that the project may be authorized under Category F in the RGP-003, “Oil spill/Hazardous substance clean up”, part (c). • The MDNR will consider whether or not to waive their wetland jurisdiction to the Local Government Unit for administering the WCA. If the MDNR maintains jurisdiction, they will likely defer to the WCA requirements for mitigation and no-loss criteria guidelines. • The USACE and the MDNR both requested that a wetland functional comparison between existing conditions and post construction conditions be completed to document whether remediation within the wetland shows changes in wetland functions through the excavation and reestablishment of wetlands. 7.5 Sequencing Analysis The following alternatives analysis was first developed and presented to MPCA in the July 2013 Focused Feasibility Study – Revision 2 (Barr, 2017). This analysis complies with WCA sequencing requirements (Minnesota Rules 8420.0520). The wetland impacts for each alternative are summarized in Table 6 below. Figures displaying the areas were the wetland impacts are located within the Site for each alternative are available in Appendix J. It is important to note that additional factors were considered when selecting the recommended alternative. Those factors are presented on Table 7 and are summarized in the following sections. 30 Table 6 Wetland Impact Areas and Floodplain Fill Volumes Remedial Alternatives Wetland Impacts Floodplain No-Loss Permanent Fill Compensatory Storage 1 No Action NA NA NA NA 2 Stormwater Management Modifications NA 15,700 sq. ft. Insignificant NA 3 Excavation for Offsite Treatment and Disposal 259,200 sq. ft. 15,700 sq. ft. Insignificant NA 4 In-Place Soil Cover NA 274,900 sq. ft. 27,500 cu. yd. Offsite 5 Onsite Consolidation with Soil Cover at West Area 178,200 sq. ft. 96,700 sq. ft. 12,500 cu. yd. Offsite 6 Onsite Consolidation with Soil Cover at Azelia Avenue Pond 257,400 sq. ft. 17,400 sq. ft. Insignificant NA 7 Limited Onsite Consolidation with Soil Cover at Building 1A Pond 242,200 sq. ft. 32,700 sq. ft. Insignificant NA 8a Limited Onsite Consolidation with Soil Cover at West Area and Additional Floodplain Offsite 230,400 sq. ft. 44,400 sq. ft. 5,000 cu. yd. Offsite 8b Limited Onsite Consolidation with Soil Cover at West Area and Additional Floodplain within West Area 239,600 sq. ft. 34,000 sq. ft. 5,000 cu. yd. Onsite (see Table 5) 7.5.1 No Action Alternative (Alternative 1) This alternative avoids wetland and floodplain impacts, but it does not provide for the protection of human health and the environment. This option is therefore removed from further consideration. 7.5.2 Stormwater Management Modifications (Alternative 2) This alternative modifies the current routing and retention of stormwater flow adjacent to and through OU5, which could aid in reducing the threat of contaminant transport to Middle Twin Lake. This alternative would create approximately 15,700 sq. ft. of permanent wetland impacts. Stormwater management alone, however, will not adequately reduce or eliminate exposure pathways to protect human health and the environment. Elements of this alternative, in combination with additional remediation techniques, are required to protect human health and the environment. Without reduction in exposure risks, this alternative alone is not a feasible option. 31 7.5.3 Excavation for Offsite Treatment and Disposal (Alternative 3) This alternative combines the stormwater management modifications of Alternative 2 with the excavation of soils that exceed cleanup levels for transportation to an out-of-state hazardous-waste incinerator for treatment followed by disposal of the ash at a hazardous waste landfill. Excavations would be backfilled with clean soil to original grade and the area would be re-vegetated and wetlands re-established. This alternative would create approximately 259,200 sq. ft. of no-loss impacts to the wetland, as well as 15,700 sq. ft. of permanent wetland impacts. The volume of floodplain fill associated with this option would be insignificant. In addition, the estimated cost of this alternative is approximately $68 million, which is unreasonable in comparison to Alternatives 5 through 8 (all of which are estimated to be between $5 and $6 million. Also, this alternative can only be implemented if the excavated soil can be accepted at an offsite location for treatment and/or disposal in accordance with the applicable rules for hazardous waste disposal. The implementation of this alternative was therefore determined to be impractical and infeasible. 7.5.4 In-Place Soil Cover (Alternative 4) This alternative combines the stormwater management modifications of Alternative 2 with the placement of a soil cover over all contaminated areas. The cap would consist of a geotextile overlaid with two feet of vegetated clean soil. This alternative would create approximately 274,900 sq. ft. of permanent impacts to the wetland. The volume of floodplain fill associated with this option is approximately 27,500 cubic yards. Based upon the estimated area of permanent wetland fill and the significant floodplain mitigation requirements, this alternative was eliminated from further consideration. 7.5.5 Onsite Consolidation with Soil Cover at West Area (Alternative 5) This alternative combines the stormwater management modifications of Alternative 2 with excavation of shallow contaminated soils from the northern portion of the West Area and from the Southern Lots for onsite consolidation. All excavated contaminated soils would be placed into a consolidation area constructed in the southern part of the West Area. The soil consolidation area would be capped with a vegetated soil cover (geotextile overlaid with 2 feet of clean soil). This alternative would create approximately 178,200 sq. ft. of no-loss impacts to the wetland and 96,700 sq. ft. of permanent wetland impacts. The volume of floodplain fill associated with this option is approximately 12,500 cubic yards. Based upon the significant wetland and floodplain mitigation requirements, this alternative was eliminated from further consideration. 7.5.6 Onsite Consolidation with Soil Cover at Azelia Avenue Pond (Alternative 6) This alternative combines the stormwater management modifications of Alternative 2 with excavation of soils that exceed cleanup levels for consolidation within the current location of a stormwater pond (Azelia Avenue Pond) on the Joslyn site. A new stormwater pond would be constructed and other stormwater 32 management modifications would be implemented. This alternative would create approximately 257,400 sq. ft. of no-loss impacts to the wetland, as well as approximately 17,400 sq. ft. of permanent impacts to the wetland. The volume of floodplain fill associated with this option is insignificant. This alternative would require several modifications to the existing monitoring and pump-out wells located within or near the proposed consolidation area. These wells are associated with active remediation, and modifications necessary to implement this alternative could risk disrupting the operations of the remediation system currently in place. Additionally, significant stormwater management changes would be required due to the proposed filling of the Azelia Avenue Pond, which is used by the existing development. Significant coordination and cooperation with the current owner of the developed portion of the Joslyn, the current tenants of the buildings, and the City of Brooklyn Center would also be required. Based on these additional factors, the implementation of this alternative was determined to be impracticable. 7.5.7 Limited Onsite Consolidation with Soil Cover at Building 1A Pond (Alternative 7) This alternative combines the stormwater management modifications of Alternative 2 with excavation of soils that exceed cleanup levels for either onsite consolidation or disposed offsite in a Subtitle D landfill. The proposed area of soil consolidation is the current location of a stormwater pond (Building 1A Pond). Modifications to the Azelia Avenue Pond would be needed to replace the functions of the filled Building 1A Pond. The consolidation area would be bounded by the Soo Line Railroad on the north and the existing fire access road for Building 1 on the south. The west side of the pile would abut OU5 and, therefore, could be expanded into OU5 as necessary. This alternative would create approximately 242,200 sq. ft. of no-loss impacts to the wetland, as well as approximately 32,700 sq. ft. of permanent wetland impacts. The volume of floodplain fill associated with this option is insignificant. The requirements for floodplain and wetland mitigation required as part of this alternative are anticipated to be less than for Alternatives 4, 5, and 8. Similar to Alternative 6, however, this alternative would require significant stormwater management changes due to the proposed filling of the Building 1A Pond. These changes would also require a significant level of coordination with the current owner of the developed portion of the Joslyn Site, the current tenants of the buildings, and the City of Brooklyn Center. Based upon these additional factors, the implementation of this alternative was determined to be impracticable. 7.5.8 Proposed Alternative – Limited Onsite Consolidation with Soil Cover (Alternative 8) The proposed alternative (Alternative 8) combines the stormwater management modifications of Alternative 2 with excavation of soils that exceed cleanup levels for either onsite consolidation or disposed offsite in a Subtitle D landfill. The proposed area of soil consolidation is within the southern part of the West Area. Two variations of Alternative 8 were evaluated in the FFS, Alternative 8A and Alternative 8B. 33 The primary difference between the variations is the location of the required compensatory floodplain storage. In Alternative 8A, the compensatory floodplain storage would be provided offsite, while in Alternative 8B, the compensatory floodplain storage would be provided within the West Area. Additionally, the biofiltration basin and berm (permanent stormwater management features) are included in the design of Alternative 8A but are not included in Alternative 8B. Alternative 8A would create approximately 230,400 sq. ft. of no-loss impacts to the wetland, as well as approximately 44,400 sq. ft. of permanent impacts to the wetland. The volume of floodplain fill associated with this option is approximately 5,000 cubic yards. Alternative 8B would create approximately 239,600 sq. ft. of no-loss impacts to the wetland, as well as approximately 34,000 sq. ft. of permanent impacts to the wetland. The volume of floodplain fill associated with this option is approximately 5,000 cubic yards. Alternative 8B, which includes compensatory floodplain storage volume within the West Area, was retained as the proposed alternative. Alternative 8B provides the best balance of criteria, including protection of human health and the environment, minimizing wetland and floodplain impacts, implementability, and cost. This is the most feasible option to best meet the purpose and need of the project while minimizing overall impact. 7.5.9 Wetland Impact Minimization In an effort to minimize wetland impact, consideration was also given to consolidating a portion of the excavated soils within the West Area, in an area of the upland zone south of the rail spur adjacent to the shoreline of Middle Twin Lake. Utilizing this approach, however, would not provide enough area for consolidation without also encroaching on a portion of the wetland. This would leave only a small portion of wetland remaining. Leaving this small area of wetland would nearly eliminate the habitat and water quality benefits that natural wetlands provide. In addition, this upland area is needed for floodplain mitigation purposes. The consolidation area was limited and moved to the east to minimize wetland impacts from 2.22 acres (Alternative 5) to 0.78 acres of wetland impact. Therefore, the proposed alternative (which permanently impacts 0.78 acres of wetland within the West Area) is the only feasible option which minimizes wetland impacts to the greatest extent possible while providing for the protection of human health and the environment. 7.6 Wetland Impacts and Mitigation 7.6.1 Wetland Impacts The proposed remediation plans would require a total of 5.50 acres of temporary wetland impacts. As described in Section 3.0, the proposed remediation would include limited excavation to remove contaminated soil to meet the MPCA’s human health and environmental criteria. The remediation area would be stabilized to prevent water quality degradation as described in Section 5.0 of this report. The 34 temporary wetland impacts qualify for No-Loss Criteria according to MN Rules 8420.0415 E, which includes “excavation and removal of contaminated substrate, when the excavated area is limited to the minimum dimensions necessary for achieving the desired purpose and stabilized to prevent water quality degradation”. The temporary wetland disturbance will affect low quality plant communities (mostly invasive species). These impacts will be minimized to the extent practical, and the vegetation will be restored with native seeding as well as shrub and tree plantings as shown in the restoration and screening plans (Appendix C, Drawing C-7 and Drawing C-8). The SCWMC Rule I requires vegetated buffer strips adjacent to the wetland. Appendix C, Drawing C-7 shows a 30 foot width buffer, measured from the approved wetland delineation boundary. The 30 foot average buffer requirement is met. The 20 foot minimum buffer requirement is met with two exception. The first exception is in the southern portion of the West Area, near the corner of the fence line adjacent to Twin Lake Avenue N. Due to the location of the existing road, the 20 foot minimum buffer cannot be met in this corner. The second location is near the southeast corner of the site, adjacent to the existing drainage swale. At the northern portion of the site, the wetland extends beyond the work area into the railroad right-of-way. Joslyn has no access to the adjacent upland buffer within this right-of-way and therefore cannot designate this area as a buffer strip. All disturbed areas within the designated buffer strip will be seeded with a native seed mix as shown in Appendix C, Drawing C-7. The southwest corner of the southern lots and south of the floodplain mitigation area are currently covered with existing trees and will not be disturbed. A buffer of trees will be planted immediately south of the floodplain mitigation area as shown on the screening plan in Appendix C, Drawing C-8. A wetland functional comparison between existing conditions and post construction conditions was completed using the BWSR Minnesota Routine Assessment Method for Evaluating Wetland Functions (MNRAM) version 3.4 and results are provided in Appendix K. The MNRAM numeric functional results show that the remediation project will provide slight improvements to the maintenance of wetland water quality, maintenance of characteristic wildlife habitat structure, and aesthetics/recreation/education/ cultural functions primarily due to the improved vegetative diversity and integrity ratings. The disturbed wetland areas will be seeded with a native seed mix (Appendix C, Drawing C-7), which will improve the average vegetative diversity and integrity rating from “low” to “moderate”. Aside from the minor numeric improvements to the wetland functions listed above, the overall functional ratings will not change and the overall classification for the wetland of “Manage 1” will not change through the excavation and reestablishment of wetlands as a result of the remediation work. The MNRAM is the accepted method for evaluating wetland functions in Minnesota; however this method does not evaluate improvements resulting from remediation of contamination on a Superfund site. Results of the remediation actions will provide the evidence of improvements to the wetland conditions at the site. The temporary wetland impacts associated with the proposed project will be restored to pre-project conditions within 6 months from the start of the activity. Follow up maintenance and monitoring for one to three years following the remediation will be conducted to document restoration of the disturbed areas. No additional wetland compensation is expected for the temporary impacts associated with this project. It is proposed that mitigation or replacement will not be necessary for the temporary wetland disturbances associated with 35 removal of contaminated substrate in the excavated area. This work will maintain or improve wetland functions and water quality and protection of human health and the environment. Permanent wetland impacts associated with the proposed alternative 8B will include: • Former Ice Chute - The elevation of the ground surface in area associated with the former ice chute will be increased to the adjacent grade to increase the residence time in the wetland, providing increased treatment of stormwater runoff post-construction. This increased surface elevation within the ice chute area will continue to be wetland consistent with the surrounding wetland to the north and south of the ice chute, however, since the final elevation will be higher than the existing elevation, the activity doesn’t meet no-loss criteria in MN Rules 8420.0415 E. Therefore this area of 0.12 acres is counted as fill within wetland and considered to be wetland impact. • Former Rail Spur - The ground surface elevation of the former rail spur will be raised to above the Ordinary High Water Level (OHWL) as recommended by the MDNR to clarify the landward extent of regulatory jurisdiction of Middle Twin Lake (MDNR, 1999). This, in combination with the proposed floodplain mitigation, will allow for increased residence time prior to discharging into the northern portion of the wetland. The area of permanent wetland fill within the former rail spur is 0.03 acres. • Consolidation Area - The consolidation area would result in permanent wetland fill of 0.63 acres. The total wetland impact for these three areas of permanent wetland fill is 0.78 acres, comprising 0.55 acres of floodplain forest, 0.05 acres of shallow marsh, and 0.18 acres of wet meadow. (Appendix J – Alternative 8B). The proposed work is the least environmental damaging practicable alternative and wetland impacts cannot be reasonably avoided or further minimized. 7.6.2 Wetland Mitigation Onsite wetland mitigation was considered, however the only possible area for this would be within the same area planned to be used for floodplain mitigation. Though the floodplain mitigation area will have wetland characteristics, the required amount of floodplain mitigation dictates that the slopes would be steeper than 8:1 as required by the WCA for wetland replacement. Therefore, created wetlands within the floodplain mitigation area will not be claimed for wetland mitigation or replacement credit. Compensation for unavoidable wetland impacts will be mitigated through the purchase of wetland bank credits. The wetland impact site is within a “less than 50 percent pre-settlement wetland area”, in Bank Service Area #7, Watershed No. 20 Mississippi River Twin Cities, and Hennepin County. There are no available wetland bank credits within the same minor watershed (Ryan Cr.). There are two bank sites within the same major watershed, one in Hennepin County and one in Washington County. Since activities undertaken on a CERCLA site by authority of CERCLA as approved or required by EPA are not required to obtain permits under Section 404 of the Clean Water Act, the wetland bank credits provided for compensation of permanent wetland impacts for this project do not need to be USACE certified. The WCA requires replacement at a 2:1 ratio for wetland impacts within a “less than 50 percent 36 pre-settlement wetland area” and within the Bank Service Area. Wetland impacts will be replaced at a 2:1 ratio by purchasing 1.56 acres of wetland credits from wetland Bank Account No. 1518, which is within a “less than 50 percent pre-settlement wetland area”, in the same major watershed (Watershed No. 20 Mississippi River Twin Cities), county (Hennepin County), and Bank Service Area (#7) as the wetland impact site. This wetland replacement plan adequately offsets unavoidable wetland losses associated with the permanent wetland fill required for this project. The Transaction Form for Withdrawal of Wetland Credits and Purchase Agreement are included in Appendix L. 7.7 Adjoining Property Owners See Appendix A. 7.8 Portion of Work Completed See Appendix A. 7.9 Status of Other Approvals See Appendix A. 7.10 Special Considerations The site was reviewed for factors of special consideration as described in the Minnesota WCA Rules 8420.0515. 7.10.1 Endangered and Threatened Species Data on the distribution of sensitive species were derived from the Natural Heritage Information System Rare Features Database (NHIS) of the MDNR through a license granted to Barr, updated 2016 (Copyright 2016, State of Minnesota, MDNR). No endangered or threatened species have been identified within a one mile radius of the proposed project area. One plant species, waterwillow (Decodon verticillatus) (State-listed as a Species of Special Concern), has been previously identified within a mile radius of the project site. According to NHIS data, the last observation of this plant in the area was in 1953. The plant species was not found while conducting wetland delineation activities in 2007, 2010, or 2012. It is unlikely that this species is located within the project area. In addition, a bald eagle (Haliaeetus leucocephalus) (State-listed as a Species of Special Concern) nest site was observed within a mile radius of the project area. Bald eagles and their nests are protected under the Bald and Golden Eagle Protection Act and the Migratory Bird Treaty Act. Project work is planned to occur during the late fall and early winter months to avoid active nesting periods. It is anticipated that the project will not have an adverse impact on bald eagles. A federally threatened species that may occur in Hennepin County is the northern long-eared bat (Myotis septentrionalis). This species winters in caves. During the summer it may roost in trees or in buildings. The 37 proposed project would occur in the fall and winter and would not affect any caves. Tree clearing during the fall and winter would be minimized to less than two acres. It is anticipated that the project will not directly affect any individuals or the habitat of this species. 7.10.2 Rare Natural Communities No rare natural communities were identified in the NHIS database within one mile radius of the project area. 7.10.3 Special Fish and Wildlife Resources No special fish and wildlife resources were identified within one mile radius of the proposed project area. 7.10.4 Cultural Resources A database search request for review and evaluation for the potential of historical and archaeological resources was submitted to the Minnesota Historical Society State Historic Preservation Office (SHPO) on March 16, 2010. In an emailed response dated March 18, 2010, SHPO’s database search did not result in the identification of any known historic structures or archaeological sites within the project area. Four historic/architecture properties were identified within the same Section as the project area (Section 10, Township 118N, Range 21W, Hennepin County), but outside of the project site location. These properties are listed in Appendix M. 7.10.5 Groundwater Sensitivity The southern portion of the site is within a wellhead protection area. 7.10.6 Sensitive Surface Waters There are no outstanding resource value waters as listed in MN Rules part 7050.0180 or designated trout waters within a one mile radius of the proposed project area. 7.10.7 Education or Research Use The proposed wetland impact area is not used for educational or research purposes. 7.10.8 Waste Disposal Sites The project is a Federal Superfund site on the National Priorities List. The proposed project will be conducted according to U.S. EPA and MPCA regulations. 7.10.9 Consistency with Other Plans As indicated in Section 1.1.2.1, this permit application has been prepared according to USACE, MDNR, WCA, and SCWMC rules and standards. 38 8.0 Construction Sequencing The following construction sequencing is anticipated for the OU5 work: 1. Install sediment control practices on all downgradient perimeters before any upgradient land disturbing activities begin, including orange construction fencing for areas not to be disturbed, silt fence, and flotation silt curtain, and sheet pile. 2. Install decontamination pad and hosing. 3. Remove, decontaminate and dispose of existing perimeter fence, Building 1B Pond outlet pipe, and miscellaneous debris. 4. Install rock construction entrance. 5. Clear and grub construction area. Chip woody material and consolidate or transport and dispose offsite as indicated in Drawing and Specifications. 6. Install stormwater diversion infrastructure including temporary berm and west portion of temporary berm and pipe to lake. 7. Dewater, excavate contaminated material and backfill in areas of stormwater diversion infrastructure including north of temporary sheet pile, south West Area strip, and Southern Lots. Excavated material shall be stockpiled for offsite disposal, or consolidated in the consolidation area as required by the Drawings and Specifications. Backfill excavated areas as indicated in the Drawings and Specifications. 8. Install riprap and filter for Building 1A Pond outlet and pipe to lake outlet. 9. Install erosion control blanket and rock check dams north of temporary sheet pile. 10. Dewater and excavate contaminated soil from West Area sub-areas to be transported offsite and dispose of at a Subtitle D landfill in accordance with the Drawings and Specifications. 11. Dewater and excavate contaminated soils from West Area sub-areas to be consolidated and consolidate onsite as indicated by Drawings and Specifications. 12. Backfill West Area sub-areas as indicated in Drawings and Specifications. 13. Construct onsite floodplain mitigation as indicated in Drawings and Specifications. 14. Construct consolidation area cap as indicated in Drawings and Specifications. 15. Install Building 1B Pond outlet. 16. Remove temporary berm and construct east portion of permanent berm. 17. Smooth and finish grade site. 18. Seed wetland, upland, floodplain mitigation, and consolidations areas and plant trees as indicated in Drawings and Specifications. 19. Remove decontamination pad and hosing. 39 20. Install new fence around OU5 area. 21. Remove temporary erosion control and sediment control measures after 70% vegetative cover has been established. 40 9.0 References Barr, 1996. Site History: Joslyn Manufacturing Company – Brooklyn Center, Minnesota. May 1996. Barr, 2000. Sampling and Analysis Plan – Supplemental West Area Characterization, Joslyn Manufacturing Co. Site, Brooklyn Center, MN. July, Revised October 2000. Barr, 2003. West Area Remedial Investigation Report, Joslyn Manufacturing Former Wood Treating Site, Brooklyn Center, Minnesota. October 2003. Barr, 2005. Letter from Dale Finnesgaard (Barr) to David Douglas (MPCA) regarding Report of Investigation Results- Residential Lots South of the West Area, Joslyn Manufacturing Company Site; Brooklyn Center, Minnesota. May 9, 2005. Barr, 2017. Focused Feasibility Study – REVISION 3, Operable Unit 5 – West Area Soils, Joslyn Manufacturing & Supply Co. Site, Brooklyn Center, Minnesota. January 2017. Board of Water and Soil Resources, 2010. Minnesota Routine Assessment Methodology for Evaluating Wetland Functions, Version 3.4. City of Brooklyn Center, 2000. Brooklyn Center Comprehensive Plan 2020. January 2000. Cowardin, L.M., V. Carter, F.C. Golet, R.T. LaRoe. 1979. Classification of Wetlands and Deepwater Habitats of the United States. U.S. Fish and Wildlife Service, FWS/OBS079/31, 103 pp. Eggers, S.D. and Reed, D.M. 1997. Wetland Plants and Plant Communities of Minnesota and Wisconsin. U.S. Army Corps of Engineers, St. Paul District. St. Paul, Minnesota. Federal Emergency Management Agency (FEMA), 2004. Flood Insurance Rate Map (FIRM). Map Number 27053C0212E. September 2, 2004. Federal Emergency Management Agency (FEMA). Unpublished Digital Flood Insurance Rate Map (DFIRM) for Hennepin County. Joslyn Manufacturing Company (Joslyn), 2004. Letter from Carl Grabinski (Joslyn) to David Douglas (MPCA) regarding Joslyn Manufacturing Company (Joslyn) Superfund Site. September 1, 2004. Minnesota Department of Health (MDH), 2002. Public Health Assessment, Joslyn Manufacturing and Supply Company Site, West Area, City of Brooklyn Center, Hennepin County, Minnesota. CERLIS No. MND044799856. August 29, 2002. Minnesota Pollution Control Agency (MPCA), 1985. Response Order by Consent for Joslyn Mfg. & Supply Co. May 10, 1985. Minnesota Pollution Control Agency (MPCA), 1989. Record of Decision for Joslyn Manufacturing and Supply Company Site. July 31, 1989. Minnesota Pollution Control Agency (MPCA), 1998a. Letter from James Kelly (MPCA) to Paul Hyde (Real Estate Recycling) regarding Joslyn Site, MPCA Project Number 9730. November 2, 1998. 41 Minnesota Pollution Control Agency (MPCA), Site Remediation Section, 1998b. Working Drafts of Risk- Based Site Evaluation Manual, Glossary of RBSE Terms and Concepts. Minnesota Pollution Control Agency (MPCA), 2000. Protecting Water Quality in Urban Areas. March 1, 2000. Minnesota Pollution Control Agency (MPCA), 2004a. Five Year Review Report, Third Five-Year Review Report for Joslyn Manufacturing and Supply Company. July 2004. Minnesota Pollution Control Agency (MPCA), 2004b. Letter from David Douglas (MPCA) to Ron Warren (city of Brooklyn Center) regarding Joslyn Manufacturing and Supply Company Superfund Site. August 16, 2004. Minnesota Pollution Control Agency (MPCA), 2013. General Permit Authorization to Discharge Stormwater Associated with Construction Activity Under the National Pollutant Discharge Elimination. August 1, 2008. Minnesota Pollution Control Agency (MPCA), 2014. Letter from Steven Schoff (MPCA) to Carl Grabinski (Joslyn) regarding Approval of Focused Feasibility Study – Revision 2 for OU5, West Area Soils at the Joslyn Manufacturing and Supply Company Superfund Site. March 5, 2014. Minnesota Pollution Control Agency (MPCA), 2017. Minnesota Stormwater Manual, Last updated March 2, 2017. https://stormwater.pca.state.mn.us/index.php?title=Main_Page&oldid=31892 National Oceanic and Atmospheric Administration (NOAA), 2013. NOAA Atlas Precipitation-Frequency Atlas of the United States, Volume 8 Version 2.0. April 2013. Shingle Creek Watershed Management Commission (SCWMC), 2013. Shingle Creek and West Mississippi Watershed Management Commissions Rules and Standards. Revisions effective April 11, 2013. Amended July 11, 2013. U.S. Department of Agriculture, Natural Resources Conservation Service. 1983. Soil Survey of Hennepin County, Minnesota. Washington, D.C. U. S. Department of Agriculture, Natural Resources Conservation Service. 2016. Field Indicators of Hydric Soils in the United States, Version 8.0. G.W. Hurt and L.M. Vasilas (eds.). USDA, NRCS, in cooperation with the National Technical Committee for Hydric Soils. U.S. Army Corps of Engineers. 1987. 1987 U.S. Army Corps of Engineers Wetland Delineation Manual. Wetlands Research Program Technical Report Y-87-1 (on-line edition). Waterways Experiment Station, Vicksburg, Mississippi. U.S. Army Corps of Engineers. Regional Supplement to the Corps of Engineers Wetland Delineation Manual: Midwest Region. August 2010. Wetlands Regulatory Assistance Program. U.S. Army Corps of Engineers. 2012. National Wetland Plant List, Midwest Region. Robert W. Lichvar. Cold Regions Research and Engineering Laboratory, U.S. Army Engineer Research and Development Center, Hanover, NH (http://rsgisias.crrel.usace.army.mil/NWPL/). 2012 List was used for the 2012 wetland delineation. The updated 2016 list (Lichvar, R.W., D.L. Banks, W.N. Kirchner, and N.C. Melvin. 2016. 42 The National Wetland Plant List: 2016 wetland ratings. Phytoneuron 2016-30: 1-17. Published 28 April 2016. ISSN 2153 733X) does not change wetland delineation results. U.S. Fish and Wildlife Service. 1956. Wetlands of the United States Circular 39. U.S. Government Printing Office, Washington, D.C. United States Environmental Protection Agency (U.S. EPA), 1980. Comprehensive Environmental Response, Compensation and Liability Act (CERCLA). U.S. House of Representatives, U.S. Code. Title 42, Chap. 103. United States Environmental Protection Agency (U.S. EPA), 1983. Results of the National Urban Runoff Program, Volume 1- Final Report. December 1983. United States Environmental Protection Agency (U.S. EPA), 1986. Superfund Amendments and Reauthorization Act (SARA). U.S. House of Representatives, U.S. Code Title 42, Chap. 103. October 17, 1986. United States Environmental Protection Agency (U.S. EPA), 1994. National Oil and Hazardous Substances Pollution Contingency Plan. 40 CFR 300. September 15, 1994. Wenck Associates, Incorporated (Wenck), 2007. Twin and Ryan Lakes TMDL Implementation Plan. Prepared for Shingle Creek Water Management Commission, Minnesota Pollution Control Agency. Wenck File #1240. November 2007. Wenck Associates, Incorporated (Wenck), 2009. Email from Todd Shoemaker (Wenck) to Sheila Sahu (Barr), regarding Water Levels for Upper, Middle, and Lower Twin Lakes- Brooklyn Center, MN. March 13, 2009. Tables Table 7 Comparative Analysis of Alternatives Joslyn Manufacturing Supply Co. Brooklyn Center, MN Table 4 Page 1 of 2 Additional Considerations4 Overall Protection of Human Health and the Environment5 Compliance with ARARs 6 Long-Term Effectiveness and Permanence7 Reduction of Toxicity, Mobility, or Volume through Treatment8 Short Term Effectiveness9 Implementability10 Estimated Cost11 State Acceptance12 Local Acceptance13 Floodplain and Wetland Mitigation14 Alternative 1 - No Action (Fence monitoring only)○NA $0.5M NA Alternative 2 - Stormwater Management Modifications ○● ◔ Limited long-term effectiveness ◔ Does not significantly alter toxicity or volume of contamination, does not reduce mobility ● Short estimated potential exposure ● No additional work required $2.3M 15,700 sq. ft. of permanent wetland impacts; insignificant floodplain fill Alternative 3 - Excavation for Offsite Treatment and Disposal ●● ● Greatest long-term effectiveness by permanently eliminating exposure pathways ● Reduces toxicity and volume through treatment, may not reduce mobility ◔ Longer estimated potential exposure to COCs; consolidation offsite ◔ Complex regulatory permitting and logistical coordination required $68M 259,200 sq. ft. of "no loss" wetland impacts; 15,700 sq. ft. of permanent wetland impacts; insignificant floodplain fill Alternative 4 - In-Place Soil Cover ●● ◑ Better long-term reduction of exposure pathways than Alt. 2 ◑ Does not significantly alter toxicity or volume of contamination; would reduce mobility ◕ Short estimated potential exposure compared to Alts. 3, 6, 7, & 8 ◔ Increased administrative challenges because of the significant amount of permanent wetland impacts $15M offsite consolidation - 274,900 sq. ft. of permanent wetland impacts; 27,500 cu. yd. of floodplain fill Alternative 5 - Onsite Consolidation with Soil Cover at West Area ●● ◑ Better long-term reduction of exposure pathways than Alt. 2 ◑ Does not significantly alter toxicity or volume of contamination; would reduce mobility ◕ Short estimated potential exposure compared to Alts. 3, 6, 7, & 8 ◑ Requires significant floodplain mitigation $5M offsite consolidation - 178,200 sq. ft. of "no loss" wetland impacts; 96,700 sq. ft. of permanent wetland impacts; 12,500 cu. yd. of floodplain fill Alternative 6 - Onsite Consolidation with Soil Cover at Azelia Avenue Pond ●● ◑ Better long-term reduction of exposure pathways than Alt. 2 ◑ Does not significantly alter toxicity or volume of contamination; would reduce mobility ◑ Longer potential exposure to COCs compared to Alts. 2, 4, & 5; consolidation onsite ◑ Requires coordination with lessee of developed offsite portion of Joslyn Site; and significant stormwater management changes $5.9M offsite consolidation - 257,400 sq. ft. of "no loss" wetland impacts; 17,400 sq. ft. of permanent wetland impacts; insignificant floodplain fill Alternative 7 - Limited Onsite Consolidation with Soil Cover at Building 1A Pond ●● ◕ Better long-term effectiveness and permanence than Alts. 4, 5, & 6 by removing a portion of contaminated soil ◕ Would reduce mobility; lessens toxicity and volume of contamination by removing a portion of the contaminated soil ◑ Longer potential exposure to COCs compared to Alts. 2, 4, & 5; consolidation onsite ◑ Requires floodplain mitigation (less than Alt. 5), coordination with lessee of developed offsite portion of Joslyn Site and significant stormwater management changes $5.2M offsite consolidation - 242,200 sq. ft. of "no loss" wetland impacts; 32,700 sq. ft. of permanent impacts; insignificant floodplain fill; Alternative 8A - Limited Onsite Consolidation with Soil Cover at West Area and Additional Floodplain Offsite ●● ◕ Better long-term effectiveness and permanence than Alts. 4, 5, & 6 by removing a portion of contaminated soil ◕ Would reduce mobility; lessens toxicity and volume of contamination by removing a portion of the contaminated soil ◑ Longer potential exposure to COCs compared to Alts. 2, 4, & 5; consolidation onsite ◑ Requires offsite floodplain mitigation, and coordination with offsite property owner(s)$5.1M 230,400 sq. ft. of "no loss" wetland impacts; 44,400 sq. ft. of permanent wetland impacts; less than 6,000 cu. yds. of floodplain fill (offsite mitigation) Alternative 8B - Limited Onsite Consolidation with Soil Cover at West Area and Additional Floodplain within West Area ●● ◕ Better long-term effectiveness and permanence than Alts. 4, 5, & 6 by removing a portion of contaminated soil ◕ Would reduce mobility; lessens toxicity and volume of contamination by removing a portion of the contaminated soil ◑ Longer potential exposure to COCs compared to Alts. 2, 4, & 5; consolidation onsite ◕ Requires floodplain mitigation and would create floodplain onsite in OU5 of the Joslyn Site.$4.6M 239,600 sq. ft. of "no loss" wetland impacts, 34,000 sq. ft. of permanent wetland impacts; less than 6,000 cu. yds. of floodplain fill (onsite mitigaiton) ●Meets criteria ●High ○Does not meet criteria ◕Medium-High ◑Medium-Low ◔Low Remedial Alternatives Threshold Criteria Scale Balancing Criteria Scale Removed from further evaluation Modifying Criteria3Balancing Criteria2Threshold Criteria1 Table 7 Comparative Analysis of Alternatives Joslyn Manufacturing Supply Co. Brooklyn Center, MN Table 4 Page 2 of 2 Notes 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Statutory requirements that each alternative must satisfy to be eligible for selection. Technical criteria upon which the detailed analysis is primarily based. This assessment provides an estimate of the adverse sustainability impacts (e.g., greenhouse gas impacts, energy footprint, worker injury-accident risk) associated with implementing the remedial alternative relative to Alternative 1 (No Further Action Beyond Previous Response Actions). Sustainability impacts were estimated using the SiteWise™ green and sustainable remediation tool. Additional details regarding the sustainability impact evaluation are in Appendix B. This assessment reflects the state’s (or support agency’s) apparent preferences among or concerns about alternatives. This assessment will be completed after the public comment period. This assessment reflects the community’s apparent preferences among or concerns about alternatives. This assessment will be completed after the public comment period. This assessment quantifies the impact to the floodplain and wetland for each alternative. It is assumed that wetland regulatory agencies will deem the temporary wetland impacts (i.e., excavation of contaminated soils and in-place restoration of wetland to existing elevations) as "no loss", while permanent impacts will require offsite mitigation at a 2.5:1 ratio. The assessment against this criterion examines the effectiveness of alternatives in protecting human health and the environment during the construction and implementation of a remedy until response objectives have been met. This assessment evaluates the technical and administrative feasibility of alternatives and the availability of required goods and services. Alternatives 2-8 require work in wetlands and the associated regulatory agency coordination and permitting (MDNR, SCWMC). This assessment evaluates the capital and operation and maintenance (O&M) costs of each alternative. Evaluation of state and community acceptance to implemented remedial actions. Additional considerations provide further details on the impact of remedial actions on the community. Additional considerations could be balancing or modifying criteria. The assessment against this criterion describes how the alternative, as a whole, achieves and maintains protection of human health and the environment. The assessment against this criterion describes how the alternative complies with ARARs, or if a waiver is required and how it is justified. The assessment also addresses other information from advisories, criteria, and guidance that the lead and support agencies have agreed is "to be considered". It is generally understood that each of the alternatives included in this FFS can, with appropriate design and planning, meet ARARs and TBCs. The assessment against this criterion evaluates the long-term effectiveness of alternatives in maintaining protection of human health and the environment after response objectives have been met. The assessment against this criterion evaluates the anticipated performance of the specific treatment technologies an alternative may employ. Figures 481 JOSLYN SITE WEST AREA SOUTHERN LOTS Middle Twin Lake Lower Twin Lake Upper Twin Lake Ryan Lake 49th AveFrance AveL a k e l a n d Av e France Ave NHowe Inc. 45th Ave N 100 4152 !;NBarr Footer: Date: 8/13/2010 12:31:11 PM File: I:\Projects\23\27\110\GIS\Maps\Permit Application_OU5\Figure 1_Site Location Map.mxd User: ss11,000 0 1,000 Feet FIGURE 1 SITE LOCATION MAP JOSLYN MANUFACTURING & SUPPLY CO. BROOKLYN CENTER, MINNESOTA July 2018 Record of Decision Operable Unit 5- Soils from West Area and Southern Lots Summary of Remedial Alternative Selection Joslyn Manufacturing & Supply Co. Site Superfund cleanup Minnesota Pollution Control Agency 520 Lafayette Road North | Saint Paul, MN 55155-4194 | 651-296-6300 | 800-657-3864 | Or use your preferred relay service. | Info.pca@state.mn.us This report is available in alternative formats upon request, and online at www.pca.state.mn.us. Document number: c-s3-23a Authors Andri Dahlmeier Steve Schoff Document support by Barr Engineering The MPCA is reducing printing and mailing costs by using the Internet to distribute reports and information to wider audience. Visit our website for more information. MPCA reports are printed on 100% post- consumer recycled content paper manufactured without chlorine or chlorine derivatives. i Contents Part 1: The declaration ............................................................................................................................. 1 1.1. Site name and location......................................................................................................... 1 1.2 Statement of basis and purpose .......................................................................................... 1 1.3 Assessment of site ................................................................................................................ 1 1.4 Description of Selected Remedy .......................................................................................... 1 1.5 Statutory determinations ..................................................................................................... 2 1.6 Data certification checklist ................................................................................................... 3 1.7 Authorizing signatures ......................................................................................................... 3 Part 2: The decision summary ................................................................................................................... 4 2.1 Site name, location, and brief description ........................................................................... 4 2.2 Site history and enforcement activities ............................................................................... 4 2.3 Community participation ..................................................................................................... 9 2.4 Scope and role of operable unit ........................................................................................... 9 2.5 Site characteristics ............................................................................................................. 10 2.6 Current and potential future land and water use .............................................................. 16 2.7 Summary of site risks ......................................................................................................... 17 2.8 Remedial action objectives ................................................................................................ 24 2.9 Description of alternatives ................................................................................................. 25 2.10 Comparative analysis of alternatives ................................................................................. 31 2.11 Selected Remedy ................................................................................................................ 35 2.12 Statutory determinations ................................................................................................... 38 2.13 Documentation of significant changes for preferred alternative of proposed plan .......... 39 2.14 References.......................................................................................................................... 39 Part 3: Responsiveness summary ............................................................................................................ 43 Record of Decision Operable Unit 5-Soils from West Area and Minnesota Pollution Control Agency Southern Lots Summary of Remedial Alternative Selection Joslyn Manufacturing & Supply Co. Site • July 2018 1 Part 1: The declaration 1.1. Site name and location This Record of Decision (ROD) is for the Joslyn Manufacturing & Supply Co. Site (Joslyn Site, or Site), Operable Unit 5 (OU5), which is located north of the intersection of Azelia Avenue North and Lakebreeze Avenue North in Brooklyn Center, Hennepin County, Minnesota (Figure 1). The United States Environmental Protection Agency (EPA) Site Identification Number is MND044799856. OU5 consists of contaminated soils remaining at the Joslyn Site in the 11.1-acre west area (West Area) and two residential lots totaling 0.56 acres that adjoin the West Area to the south (Southern Lots; Figure 1). All of the land encompassing OU5, the West Area, and the Southern Lots is owned by Joslyn Manufacturing & Supply Co. (Joslyn). The Joslyn Site is on the EPA’s National Priorities List (NPL) and the Minnesota Pollution Control Agency’s (MPCA) Permanent List of Priorities (PLP). MPCA oversees remedy selection and cleanup at the Site as a State-enforcement lead Site under the Minnesota Environmental Response and Liability Act of 1983 (MERLA). 1.2 Statement of basis and purpose This decision document presents the remedial actions selected by the MPCA (Selected Remedy, or Remedy) to address contaminated soils for at the Joslyn Site, OU5. The Selected Remedy was chosen in accordance with the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA, or Superfund), as amended by Superfund Amendments and Reauthorization Act of 1986 (SARA), the Minnesota Environmental Response and Liability Act of 1983 (MERLA), and, to the extent practicable, the National Oil and Hazardous Substances Pollution Contingency Plan (NCP), 40 CFR Part 300, as amended. This decision is based on the administrative record for the Joslyn Site (Administrative Record). The MPCA has selected the remedial actions for the Site. The proposed remedy has been shared with EPA Region V and EPA Region V has not notified MPCA of any inconsistencies with Federal Superfund Law (CERCLA) and the NCP. The Selected Remedy will be implemented under the May 30, 1985 Response Order by Consent between Joslyn and the MPCA (1985 Consent Order; MPCA, 1985). 1.3 Assessment of site The Selected Remedy identified in this ROD is necessary to protect public health or the environment from actual or threatened releases of hazardous substances into the environment. 1.4 Description of Selected Remedy The Selected Remedy for OU5 will address contaminated soils through the elimination of exposure pathways for protection of potential human and ecological receptors. Eight remedial alternatives were evaluated in the OU5 Focused Feasibility Study (FFS; Barr, 2017). The Selected Remedy, Alternative 8B of the FFS, will use offsite disposal and onsite consolidation and containment of these soils to eliminate the exposure pathways. The major components of the Selected Remedy for OU5 include: Record of Decision Operable Unit 5-Soils from West Area and Minnesota Pollution Control Agency Southern Lots Summary of Remedial Alternative Selection Joslyn Manufacturing & Supply Co. Site • July 2018 2 Implementation of surface water engineering controls to protect Middle Twin Lake. Excavation of shallow soils with dioxin concentrations above the selected cleanup goals to depths of one to four feet, from the West Area and the Southern Lots (approximately 30,000 cubic yards). Consolidation of a portion of the excavated soils (approximately 10,000 cubic yards) to an onsite consolidation area in the southeastern portion of the West Area. Containment and isolation of contaminated soil within the onsite consolidation area using a non-woven geotextile fabric overlaid with a two-foot thick vegetative soil cover. Offsite disposal of a portion of the excavated soils (approximately 20,000 cubic yards) at a Subtitle D landfill. Backfilling of excavations to original grade with clean soil, re-vegetation, and wetland re- establishment to the extent possible in the West Area. Mitigation and restoration of any wetland or floodplain impacts. Implementation of post-construction site inspections, maintenance, and contingency action plans to protect the remedy. Establishment of institutional controls (i.e., restrictive covenant) to restrict future land use and groundwater use. Five-year reviews of the remedy to ensure protectiveness is maintained. The Selected Remedy for OU5 is compatible with the remedies for the other Operable Units at the Joslyn Site that are currently ongoing or have been completed: OU1, OU2, and OU3 (groundwater monitoring and dense non-aqueous phase liquid [DNAPL] pump-out that is ongoing) and OU4 (land treatment of contaminated soils that has been completed). OU1, OU2, OU3, and OU4 are defined and their remedies described in detail in the 1989 ROD for the Joslyn Site (MPCA, 1989). The potential risk to human and ecological receptors posed within OU5 arises from possible direct contact with contaminated soil. The Selected Remedy addresses this risk by eliminating the direct contact pathway. Contaminants in the soils in OU5 are unlikely to migrate within the soil or from the soil to other media due to low mobility of those contaminants. 1.5 Statutory determinations The Selected Remedy is protective of human health and the environment, and complies with Federal and State requirements that are applicable or relevant and appropriate to the remedial action, is cost- effective, and utilizes permanent solutions and alternative treatment (or resource recovery) technologies to the maximum extent practicable. The statutory preference is for treatment that reduces toxicity, mobility, or volume of hazardous substances, pollutants, or contaminants as a principal element of the remedy. The Selected Remedy for OU5 does not satisfy the statutory preference for treatment on its own, but taken in conjunction with the remedy for OU4 (land treatment of contaminated soils), the statutory preference for treatment has been satisfied for the Joslyn Site as a whole. The contaminants being addressed in OU5 are essentially immobile. Under the Selected Remedy for OU5, soils classified as principal threat wastes will be contained and isolated on site below a vegetative cover. The Selected Remedy eliminates the potential for both human and ecological exposure to contaminants in the soil. The alternative remedial actions that satisfy the statutory preference for treatment were not selected because of technical feasibility, consideration of short-term risk to human health and the environment, and extraordinarily high cost. Because the Selected Remedy will result in hazardous substances, pollutants, or contaminants remaining on site, the MPCA will review the Remedy in accordance with 42 USC§ 9621(c) no less often than every five years after initiation of remedial action to ensure that the Remedy is, or will be, protective of human health and the environment. 1.6 Data certification checklist The following information is included in the Decision Summary section of this ROD (Part 2). Additional information can be found in the Administrative Record file for the Joslyn Site. •Chemicals of concern and their respective concentrations (Section 2.54) •Baseline risk represented by the chemicals of concern (Section 2.7) •Cleanup levels established for chemicals of concern and the basis for these levels (Section 2.8) •How source materials constituting principal threats are addressed (Section 2.10.4.1) •Current and reasonably anticipated future land use assumptions and current and potential future beneficial uses of groundwater used in the Baseline Risk Assessment and ROD (Section 2.6). •Potential land and groundwater use that will be available at the site as a result of the Selected Remedy (Section 2.11.4) •Estimated capital; annual operation and maintenance (O&M); and total present worth costs, discount rate, and the number of years over which the remedy cost estimates are projected (Section 2.9) •Key factors that led to selecting the remedy (Section 2.11.1) 1. 7 Authorizing signatures This ROD documents the Selected Remedy for Operable Unit 5 of the Joslyn Site. This remedy was selected by the MPCA. Division Director Remediation Division Minnesota Pollution Control Agency Record of Decision Operable Unit S-Soils from West Area and Southern Lots Summary of Remedial Alternative Selection Joslyn Manufacturing & Supply Co. Site • July 2018 Minnesota Pollution Control Agency 3 Record of Decision Operable Unit 5-Soils from West Area and Minnesota Pollution Control Agency Southern Lots Summary of Remedial Alternative Selection Joslyn Manufacturing & Supply Co. Site • July 2018 4 Part 2: The decision summary This Record of Decision documents the selection of a Remedy by the MPCA for OU5 at the Joslyn Site. This Remedy has been selected in accordance with MERLA and following the process set forth in the 1985 Consent Order. In accordance with the 1985 Consent Order, Joslyn has funded the investigations and remedial actions at the Joslyn Site and will fund the OU5 remedy. Pursuant to an agreement between the MPCA and the EPA entitled “Minnesota Pollution Control Agency Enforcement Deferral Pilot Project” dated June 20, 1995 (1995 Deferral Pilot Agreement), the MPCA is the lead agency for enforcement of Superfund cleanup requirements for the Joslyn Site. The decision to select this Remedy is not inconsistent with the requirements of CERCLA and the NCP, and complies with the terms and conditions of the 1995 Deferral Pilot Agreement. 2.1 Site name, location, and brief description The Joslyn Site is a former wood treatment facility located north of the intersection of Azelia Avenue North and Lakebreeze Avenue North in Brooklyn Center, Hennepin County, Minnesota. The MPCA is the lead agency for the Joslyn Site and the EPA Site Identification Number is MND044799856. Figure 1 shows the location of the Joslyn Site. The Joslyn Site is bounded to the south by residential development, by Middle Twin Lake to the west, by an active Canadian Pacific Railway track to the north, and State Highway 100 to the east (Figure 1). The Joslyn Site is now divided into two discrete areas: a 25-acre portion that has been delisted and redeveloped for commercial use, and an 11.1-acre portion known as the West Area that remains undeveloped (Figure 1). The West Area, which remains on the MPCA’s PLP and the EPA’s NPL, is designated as part of OU5. Two undeveloped residential lots acquired by Joslyn that adjoin the West Area to the south totaling approximately 0.56 acres (southern lots) constitute the remainder of OU5. The 25-acre portion of the Joslyn Site was redeveloped for light industrial use after extensive environmental investigations and remedial actions as described in Section 2.2.3.1. The West Area is comprised of wetlands and wooded uplands and the Southern Lots are well vegetated, with trees and shrubs covering the majority of both parcels. The majority of the West Area and over half of the area of the Southern Lots are located within both the 100-year floodplain elevation and the ordinary high water level (OHWL) of Middle Twin Lake. 2.2 Site history and enforcement activities 2.2.1 Operational history The Joslyn Site was used for wood treating operations from the 1920s until its closure in 1980. The property and wood treating operations were originally owned and operated by Naugle Pole and Tie Company who sold the property to Consolidated Pole Treating Company sometime in the 1940s. Joslyn was part owner of the Consolidated Pole Treating Company and eventually obtained sole ownership of the Joslyn Site in the 1960s. Wood treatment operations ended in 1980 (MPCA, 1985). The primary purpose of the Joslyn wood treating operations was the production of treated or preserved wood utility poles. The Joslyn facility also produced lesser quantities of treated wood railroad ties, treated wood pilings, and cross-arms for wood utility poles. Three methods of wood treatment were Record of Decision Operable Unit 5-Soils from West Area and Minnesota Pollution Control Agency Southern Lots Summary of Remedial Alternative Selection Joslyn Manufacturing & Supply Co. Site • July 2018 5 used at the Joslyn facility: butt-dip treatment (origin to about 1965), thermal treatment (1940s to close), and pressure treatment (1965 to close). The wood preservatives used at this facility included creosote, pentachlorophenol (PCP), and copper-chromium arsenate. Creosote was the only treatment fluid used in butt-dip treatment and PCP was the only treatment fluid used in the thermal treatment process. Although all three of the preservatives were used (at different times) in the pressure treatment system, PCP was the primary treating chemical used in this process. Both the butt-dip and thermal treatment methods produced a sludge consisting of soil, grit, wood scraps, wood sugars (sap), and residual treating fluid. The sludge was periodically removed from the process area and buried in shallow pits on the Joslyn Site. Throughout the history of the Joslyn Site, fill was used to increase the usable area for wood treatment and/or storage. The West Area was not used for day-to-day wood treating operations; however, Pond C at the West Area was used for disposal of boiler blowdown water. The boilers provided steam for butt-dip and thermal treatments and for operation of stiff-leg cranes used on site. Boiler blowdown water containing lubricating oils was disposed at Pond C in addition to other areas at the Joslyn Site. Historical information, including aerial photographs and Minnesota Department of Health (MDH) reports from 1944 and 1950, indicates that Pond C was originally constructed after 1937, was operational in 1944, and no longer received boiler blowdown water as of 1950.  Although the West Area is located west of the majority of the historic operations at the Joslyn facility, contamination may have spread to the West Area through the following mechanisms:  Use of Pond C  Sludge disposal/burial  Placement of fill  Overland flow of stormwater runoff and eroded soils The Southern Lots are zoned for residential use and have never been developed. The Southern Lots were acquired by Joslyn in 2005. The Southern Lots may have been affected by contaminated stormwater runoff and eroded soils from the West Area during flood events. Additionally, historical aerial photographs indicated that small-scale disturbances, which may have included filling, have occurred at the Southern Lots. 2.2.2 Enforcement actions In 1961, City of Brooklyn Center staff observed phenol contamination in several residential wells near the Joslyn Site, and in 1980, the MPCA also observed PCP and phenols in several nearby residential wells. Several investigations conducted by Joslyn in the early 1980s indicated that groundwater and soils at the Joslyn Site were contaminated with compounds associated with the wood treating process (e.g., phenols and polynuclear aromatic hydrocarbons [PAHs]). On September 27, 1983, the MPCA issued a Request for Response Action (RFRA) to Joslyn pursuant to MERLA requesting that Joslyn undertake remedial actions to abate the release of hazardous substances at the Joslyn Site. On September 21, 1984, the Joslyn Site was listed by EPA on the NPL due to soil and groundwater contamination. Under the terms of the 1985 Consent Order, Joslyn is responsible for the costs associated with the investigation and remedial actions undertaken. Investigation of the Joslyn Site was substantially completed by 1988. Record of Decision Operable Unit 5-Soils from West Area and Minnesota Pollution Control Agency Southern Lots Summary of Remedial Alternative Selection Joslyn Manufacturing & Supply Co. Site • July 2018 6 2.2.3 Historical investigation and remedial actions 2.2.3.1 Actions associated with 1989 record of decision – OU1 through OU4 As a result of the investigations conducted under the 1985 Consent Order, interim response actions were conducted in 1988 when 18,818 tons of contaminated soils were excavated from the Joslyn Site and disposed of at a permitted hazardous waste landfill in Oklahoma. On July 31, 1989, a Record of Decision (1989 ROD; MPCA, 1989) was issued for operable units (OUs) 1 through 4. The 1989 ROD defined four operable units at the Joslyn Site.  OU1 consists of the upper unit of the unconsolidated aquifer (shallow upper aquifer)  OU2 consists of the middle unit of the unconsolidated aquifer (middle sands)  OU3 consists of the accumulation of dense non-aqueous phase liquid (DNAPL) in a subsurface aquitard located near well W251  OU4 consists of contaminated soil remaining after the completion of the interim response action completed in 1988 The 1989 ROD also specified remedies for the four operable units defined at the Joslyn Site.  Installation, operation, and maintenance of a groundwater pump-out system (OU1 for shallow groundwater and OU2 for middle-sand groundwater)  Installation, operation, and maintenance of a DNAPL pump-out system (OU3)  Onsite biological treatment of the contaminated soil that remained after the 1988 interim response action (OU4)  Regional groundwater and surface water monitoring (OU1, OU2, and OU3) The groundwater pump-out system to address OU1 and OU2 began operating in February 1989 and the DNAPL recovery system for OU3 began operating in December 1995. The groundwater and DNAPL remedies (OU1, OU2, and OU3) continue to operate effectively (MPCA, 2009). The OU4 remedy consisted of excavation of soil contaminated with the wood treating fluids, followed by biological treatment of those soils in an onsite land treatment unit (LTU). The OU4 remedy was targeted at soils in the saturated zone, although excavation occurred below the water table where practicable as required by the 1989 ROD. The 1989 ROD also specified that following soil treatment, the LTU was to be closed. The LTU was constructed in 1989 and treatment of approximately 90,000 cubic yards of soil occurred from 1989 to 1997. The MPCA approved the cleanup of soils at the Joslyn Site for a general industrial use scenario. With the exception of the West Area, most of the Joslyn Site was redeveloped in three separate phases of redevelopment. Redevelopment activities were undertaken by Real Estate Recycling, Inc. with the cooperation of Joslyn and under the oversight of the MPCA. Since 1999, three buildings for light industrial use, associated parking lots, stormwater ponds, and an extension of Azelia Avenue have been constructed. Site redevelopment and its associated buildings, driveways, and areas of clean-vegetated soil, provided acceptable conditions for the closure of the LTU. After closure of the LTU, the OU4 portion of the remedy was complete on the developed portion of the Joslyn Site resulting in a partial deletion of the site from the MERLA PLP in 2000 (MPCA, 2000) and from the CERCLA NPL in 2002 (EPA, 2002). Further information regarding enforcement activities at the Joslyn Site related to OU1 through OU4 are available in the 1985 Consent Order, the 1989 ROD, and in Five-Year Reviews completed by MPCA in 1995, 1999, 2004, and 2009 (MPCA, 1995; MPCA, 1999a; MPCA, 2004a; MPCA, 2009). Record of Decision Operable Unit 5-Soils from West Area and Minnesota Pollution Control Agency Southern Lots Summary of Remedial Alternative Selection Joslyn Manufacturing & Supply Co. Site • July 2018 7 2.2.3.2 Historical West Area investigations and remedial actions associated with OU4 Portions of the West Area have been investigated and/or remediated as part of the implementation of the OU4 remedy (excavation and onsite land treatment of contaminated soils). Investigations and/or response actions to address portions of the West Area during remedial actions associated with OU4 were conducted in 1981, 1986, 1997, 1998, and 1999. These investigations are described in detail in other documents, but are summarized in the following paragraphs by area and excavation areas are shown on Figure 2. The 1998 and 1999 release sampling investigation is discussed in this section only as it relates to the identification of contaminated soils that were subsequently remediated as part of the OU4 remedy. The release sampling investigation as it relates to OU5 is discussed in Section 2.2.3.3. Pond C area An investigation of the Joslyn Site disposal ponds, including Pond C, which was located at the West Area, was conducted in 1981 (Barr, 1981). Hazardous waste, as defined at the time of the investigation, was not observed at Pond C and subsequent investigations and response actions were focused on other areas of the Joslyn Site. The Pond C area was investigated again in 1997 as part of a larger West Area investigation (Barr, 1997). Visually contaminated soil was observed during the 1997 investigation and that soil (approximately 650 cubic yards) was excavated and treated at the onsite LTU later that year (Barr, 1998). The excavation was backfilled with clean soil from an offsite source. Ice chute and ditch from Pond C An apparent former ice chute, a manmade ditch that was reportedly used to mine ice blocks from Middle Twin Lake, is located at the northern portion of the West Area. During the use of onsite disposal Pond C, a drainage ditch was reportedly constructed from the northern dike of the pond to the ice chute. Two borings were placed in the former ice chute area and one boring in the drainage ditch during a 1997 investigation (Barr, 1997). Samples were collected from each boring for analysis for PAHs and PCP. Low-level PAHs were observed in one sample obtained from the former ice chute area. All other samples were non-detect for PAHs. PCP was not detected in any of the samples. Area west of Pond A An onsite wastewater disposal pond, Pond A, was located immediately east of the West Area. The “Area West of Pond A” was specifically identified in the 1985 Consent Order because the area contained visually impacted soil and debris. Investigations conducted in 1986 in this area were used to delineate contaminated soil extents (Barr, 1986). Approximately 2,500 cubic yards of contaminated soil was removed from this area in 1989 and treated at the onsite LTU (Barr, 1993). Onsite material was used to backfill the excavation. WA-3 Area excavation The release sampling investigation of the West Area in 1998 and 1999 indicated that a “hot spot” of visually contaminated soil was present at the southeastern portion of the West Area known as West Area-3 or WA-3 (Earth Tech, 1999a; Earth Tech, 1999b). Approximately 1,000 cubic yards of visually contaminated soil was excavated to a depth of approximately three feet from the “hot spot” area and disposed off site at a RCRA Subtitle C disposal facility (Barr, 1999a). The excavation was backfilled with clean offsite soil. Western LTU dike excavation During the WA-3 area excavation described above, an area of visibly contaminated soil was identified beneath the western LTU dike. Approximately 50 cubic yards of this soil was excavated and treated at the onsite LTU (Barr, 1999b). Clean soil obtained from offsite sources was used to backfill the excavation. Record of Decision Operable Unit 5-Soils from West Area and Minnesota Pollution Control Agency Southern Lots Summary of Remedial Alternative Selection Joslyn Manufacturing & Supply Co. Site • July 2018 8 2.2.3.3 Investigations associated with OU5 Since wood treating activities were conducted on the now redeveloped portion of the Joslyn Site adjacent to the West Area from approximately 1920 to 1980, concerns were raised regarding the nature and extent of contamination in the West Area and in Middle Twin Lake located immediately adjacent to the West Area. In 1998, the MPCA requested that Joslyn conduct a soil-sampling program to assess the presence of PAHs, PCP, and dioxin/furan compounds (dioxins/furans) in accessible soils across the Joslyn Site, including at the West Area. The prospective site redeveloper conducted this investigation in 1998 and 1999 (Earth Tech, 1999a; Earth Tech, 1999b). As a result of this sampling investigation, the West Area was identified as an area requiring additional investigation and possible remediation. Following completion of the study, redevelopment activities continued, and have since been completed, on the remainder of the Joslyn Site as noted in Section 2.2.3.1. Prior to 1999, the contaminants of concern (COCs) for the Joslyn Site were listed as PAHs and PCP. Residual soil contamination was identified in West Area surface soils during the 1998 and 1999 release sampling investigation. Varying concentrations of PCP, PAHs, and dioxins/furans were observed in samples of the West Area shallow soil (Earth Tech, 1999a; Earth Tech, 1999b). After the sampling investigation in 1999, dioxin and furans were added as COCs for the West Area. Further investigation of shallow soils in the West Area was conducted in 2000 to fill identified data gaps in the 1998 and 1999 sampling investigation (Barr, 2001). In 2002 and 2003, an investigation of shallow soils, sediment, and surface water was conducted in the West Area (Barr, 2003). Results of the investigation indicated the presence of COCs at varying concentrations in shallow soils throughout the West Area and in surface water samples. Very low to non-detectable COC concentrations were observed in sediment samples. This investigation is discussed in more detail in Section 2.5.4.1. A pre-design soil investigation was completed in January 2014 (Barr, 2014) and an additional soil characterization investigation was completed in February 2015 (Barr, 2015a). Sampling activities were conducted on and adjacent to the Southern Lots in 2003, 2004, 2005, and 2009 (Barr, 2009). Results of the 2003-2005 work showed low-level concentrations of dioxin/furans in portions of the Southern Lots (Barr, 2005a). In 2009, an investigation was conducted to better define the extent of contamination of the north parcel (Barr, 2009). These investigations are discussed in more detail in Section 2.5.4.2. Data collected from each of the investigations was used to assess remedial action alternatives for OU5. 2.2.3.4 Middle Twin Lake Due to its location adjacent to the Joslyn Site, numerous investigations have been conducted at Middle Twin Lake to determine whether releases to the lake from the Joslyn Site have occurred, and if so, whether or not there are unacceptable risks to human health and the environment. A new series of studies was triggered when soil contaminated with dioxin/furans was identified in the West Area during the 1998 and 1999 release sampling investigation. This section briefly describes the studies related to Middle Twin Lake that have been conducted since 1999. In 2003, the MPCA retained an environmental consultant to collect sediment samples from Middle Twin Lake with the primary goal of determining whether COCs had been released from the Joslyn Site. The sampling results were presented in a June 2004 report, which concluded that a release of COCs from the Joslyn Site into Middle Twin Lake sediments had occurred (Bay West, 2004). Joslyn criticized the Record of Decision Operable Unit 5-Soils from West Area and Minnesota Pollution Control Agency Southern Lots Summary of Remedial Alternative Selection Joslyn Manufacturing & Supply Co. Site • July 2018 9 methodology employed in the study and disputed the conclusions cited in the report (Barr, 2006a; Joslyn, 2006). In 2004, a fish tissue study was completed on fish collected from Middle Twin Lake to help determine whether COCs had been released from the Joslyn Site, and if so, whether human health could be endangered by the consumption of fish obtained from Middle Twin Lake. The data was presented in 2005 (Barr, 2005b) and reviewed by the MDH in conjunction with the United States Department of Health and Human Services. A Health Consultation was prepared that showed that of the COCs at the Joslyn Site, only dioxin/furans were present at elevated concentrations in the fish tissue (MDH, 2006). The dioxin/furans concentrations in the tissue from Middle Twin Lake fish did not differ significantly from concentrations found by the EPA in a study of 58 lakes in Minnesota. MDH does not consider the dioxin/furans concentrations in fish in Middle Twin Lake to present a public health hazard if fish consumption advice is followed. MDH recommended that additional sediment samples be collected to determine if there is a human health risk from direct exposure to the sediments and to determine if there is a future risk to fish if sediments are disturbed. Joslyn completed an additional sediment sampling and analysis study in September 2007 and submitted results to the MPCA in a December 2007 report (Barr, 2007). The MPCA concluded that the sampling results confirmed that the concentration of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/PCDF) in sediments, both in the beach and non-beach study areas, were below the sediment screening value of 50 parts per trillion (ppt) toxicity equivalency quotient (TEQ) that was proposed by the MDH for the Joslyn Site project, and that no further assessment was necessary. 2.3 Community participation This section summarizes the community relations activities conducted by MPCA during the investigation and remedy selection process. Community participation activities included community meetings, public meetings and public notices, phone calls and emails with community members, and mailings with fact sheets and site information. Specific community participation activities performed prior to the issuance of the proposed cleanup action for OU5 (Proposed Plan) included:  Consultation with neighborhood groups  Consultation with local government agencies (City of Brooklyn Center, Shingle Creek Watershed Management Commission)  Contact by phone and email with individual community members The Proposed Plan and a summary of the proposed plan for OU5 were made available to the public in March 2017. These documents were made available on the MPCA website and mailed to citizens within the surrounding area. A public comment period was open from March 27, 2017 to May 19, 2017 and a public meeting was held on April 12, 2017. MPCA received comments from five individuals during the public comment period. MPCA’s response to comments received during this period is included in the Responsiveness Summary, which is part of this ROD. 2.4 Scope and role of operable unit Due to the complexity of many Superfund sites, remedial actions are often divided into a number of operable units based on factors including geography, specific site problems, and phases of remedial action. As noted in Section 2.2.3.1, the 1989 ROD organized remedial work at the Joslyn Site into four OUs as follows: OU1 consists of the upper unit of the unconsolidated aquifer (shallow upper aquifer); Record of Decision Operable Unit 5-Soils from West Area and Minnesota Pollution Control Agency Southern Lots Summary of Remedial Alternative Selection Joslyn Manufacturing & Supply Co. Site • July 2018 10 OU2 consists of the middle unit of the unconsolidated aquifer (middle sands); OU3 consists of the DNAPL pool located near well W251; and OU4 consists of contaminated soil remaining after the completion of the interim response action completed in 1988. The remedy outlined in the 1989 ROD included onsite biological treatment of contaminated soil (or the offsite disposal of heavily contaminated soil – soil unable to be treated biologically); operation and maintenance of a groundwater pump-out system; operation and maintenance of a DNAPL pump-out system; and regional groundwater and surface water monitoring. As noted in Section 2.2.3.1, the groundwater and DNAPL remedies (OU1, OU2, and OU3) are currently continuing to operate effectively and the OU4 portion of the remedy was complete upon closure of the LTU when portions of the Joslyn Site were redeveloped for light industrial use. OU4 was partially delisted from the Minnesota MERLA PLP on June 1, 2000 (MPCA, 2000), and partially delisted from the federal CERCLA NPL on August 16, 2002 (EPA, 2002). The subject of this ROD is a new operable unit, OU5, which consists of contaminated soils that remain at the Joslyn Site in the West Area and the Southern Lots. Soils in one or more sub-areas of OU5 exceed the human and/or ecological preliminary remediation goals (PRGs) that have been established for the Joslyn Site (see Table 5 and Section 2.8 for PRG discussion). This fifth operable unit represents the final response action for the Joslyn Site. 2.5 Site characteristics 2.5.1 Conceptual site model The conceptual site model (CSM) is a tool that helps form a picture of what is known about a site, incorporating information on the potential chemical sources, affected media, release mechanisms, chemical transport, and known or potential human and ecological receptors. Contaminated soils of OU5 exceed the human and/or ecological PRGs established by the MPCA, and therefore pose potential risks to human and ecological receptors via incidental ingestion, direct contact (dermal adsorption), and inhalation exposure pathways. Other exposure pathways, including ingestion or direct contact with both surface water and groundwater, are determined to be incomplete as a result of sampling data and the particular nature of the OU5 soil matrix. High organic content (OC) of the soil at OU5 reduces the potential magnitude of exposure through both inhalation and incidental soil ingestion. The proportion of dioxins that have the potential to volatilize from the soil matrix is reduced by the strong dioxin-soil OC binding. In addition, dioxins in this soil matrix are less bioavailable upon ingestion than dioxins in low-OC soils (Van der Berg, 2006). Nonetheless, despite the likely reduction in the magnitude of exposure, these pathways are still assumed to be potential contributors to receptor risk. Contaminated soils at OU5 are accessible to both human and ecological risk receptors, which supports the determination that the direct contact exposure pathways are complete. The MPCA has defined the “accessible” soils in the West Area as the upper three feet of the final grade (MPCA, 1998), or the upper two feet of the final grade if an underlying geotextile fabric was installed. The MPCA has defined the “accessible” soils in the Southern Lots as the upper four feet of the final grade (MPCA, 2005b). Results of the fish tissue and sediment sampling studies at Middle Twin Lake, described in Section 2.2.3.4, indicate that the surface water exposure pathway is not complete. The groundwater exposure pathway was evaluated by assessing the long-term risk of COCs leaching from contaminated Record of Decision Operable Unit 5-Soils from West Area and Minnesota Pollution Control Agency Southern Lots Summary of Remedial Alternative Selection Joslyn Manufacturing & Supply Co. Site • July 2018 11 soil in OU5 to groundwater. The presence of a high proportion of natural organic soils (i.e., peat) in the wetland portions of OU5 inhibits infiltration-based transport. Dioxins adsorb strongly to organic materials like peat and other vegetative matter. This reduces the potential for dioxins to dissolve into pore water and ultimately infiltrate groundwater. The groundwater near Middle Twin Lake flows from the lake area to the east-southeast; therefore, groundwater in the West Area does not discharge into the lake. In addition, the existing groundwater pump-out system at the Joslyn Site collects groundwater flowing from OU5, capturing it for treatment and discharge to the sanitary sewer system. In summary, throughout OU5, the exposure pathways of concern for human and ecological receptors are ingestion, inhalation, and direct dermal contact with soils that are non-conforming, or exceed the PRGs (see Table 5 and Section 2.8 for PRG discussion). A CSM for OU5 is shown on Figure 3. 2.5.2 Physical site setting As discussed above, OU5 encompasses two areas of the Joslyn Site: the West Area and the Southern Lots. The West Area consists of wetlands and wooded upland, and abuts Middle Twin Lake to the west. Surface water drains north through the central portion of the Site and flows directly to Middle Twin Lake at the northwest limit of the site. The soils consist of fill soils, native lacustrine fine sand, silts and clays, and peat in the wetland portions. Historic aerial photographs show signs of a pond (former Pond C) in the central portion of the West Area prior to 1950 (Figure 4). A waterway, or ice chute, may have once existed across the northern portion the West Area. In the mid-1960s, an embankment for a railroad spur was placed from west to east across the West Area (Figure 5). The Southern Lots, which are covered with trees and shrubs, are located south of the West Area. Roughly, half of the areas of both parcels fall within the 100-year flood elevation of Middle Twin Lake (856.0 feet above mean sea level [MSL]). Soils in the Southern Lots consist of fill, as well as native lacustrine fine sands, silts, clays, and peat. 2.5.3 Geology and hydrogeology The Joslyn Site is underlain by about 100 feet of complex glacial deposits overlying sedimentary bedrock. In general, the West Area and the Southern Lots are underlain by a mix of fill, organic-rich sands and silts, and various sand layers. Further, east, the glacial deposits are more complex, with layers of silts and clays. It appears the chain of Twin Lakes may be in a glacial meltwater channel where older glacial deposits and the St. Peter Sandstone (which underlies the rest of the Joslyn Site) were scoured out and replaced by outwash sands and lake sands. Groundwater and lake level monitoring have been conducted at the Joslyn Site for over 20 years and, except for a few periods, conditions have been relatively constant. Groundwater levels indicate flow from the area of the lake to the east-southeast. The groundwater pump-out system at the Joslyn Site to address OUs 1 and 2 captures the groundwater near the water table and in an isolated sand body at an intermediate depth. Routine monitoring of the groundwater laterally downgradient of the Joslyn Site and below the Joslyn Site in the lower aquifer confirms that the lower aquifer is protected and that the COCs are contained within the limits of the site. Record of Decision Operable Unit 5-Soils from West Area and Minnesota Pollution Control Agency Southern Lots Summary of Remedial Alternative Selection Joslyn Manufacturing & Supply Co. Site • July 2018 12 2.5.4 Nature and extent of contamination This section summarizes the nature and extent of soil contamination identified at OU5 as derived from results of previous investigations, describes potential exposure pathways, and includes a discussion of the likelihood for migration of COCs. There are no known specific and confirmed sources of the residual soil contamination identified within OU5. As discussed in Section 2.2.3.2, the OU4 remedy addressed areas of contamination in the West Area resulting from contaminated fill placement and the disposal/burial of wood treating residuals/sludges. Because the former operating portion of the wood treating site is adjacent to the West Area, it is suspected that surface water runoff from the adjacent former wood treating operations may have been the source of contamination to OU5 soils. The COCs for OU5 are therefore the following compounds related to the former wood treating operation at the Joslyn Site: carcinogenic PAHs PCP Dioxins/furans During previous investigations conducted at the West Area, the following media were sampled: soils, sediment, and surface water. As indicated in Section 2.2.3.4, based on results of recent investigations of sediments and fish tissue conducted at Middle Twin Lake, the MPCA concluded that further assessment of surface water and lake sediments would not be required. It should also be noted that groundwater and DNAPL remedies implemented under OU1, OU2, and OU3 will continue to be operated and maintained and the groundwater will continue to be monitored at the Joslyn Site. 2.5.4.1 Soil contamination – West Area Soils with elevated PAHs, PCP, and/or dioxins/furans concentrations were detected in shallow soils at the West Area during investigations conducted prior to 1999 (see Section 2.2.3.2 and Barr, 2000 for more details). As part of the release sampling investigation conducted in 1998 and 1999, the West Area was organized into a number of sub-areas (Figure 6a). The delineation of each sub-area was based on topography, history of fill placement as observed in historic aerial photographs, and vegetation patterns. WA-1, WA-2, and WA-3 are generally upland areas on the eastern edge of the West Area, adjacent to the former wood treating areas on the Joslyn Site. Historic fill placement was observed in these three sub-areas during review of Joslyn Site aerial photographs. WA-4 and WA-5 are located on the western edge of the West Area adjacent to Middle Twin Lake and consist primarily of forested upland. WA-6 is located in the south-central portion of the West Area and represents the approximate former location of Pond C. WA-6 was further subdivided into WA-6S, WA-6MID, and WA-6N based on historic site features, including the former railroad spur, which had intersected Pond C. WA-7 is a shallow marsh located in the north-central portion of the West Area. WA-8 is defined as the east-west former rail spur located in the central portion of the West Area. Joslyn conducted additional soil sampling in 2003 along east-west transects across the West Area to obtain data to more fully characterize the potential ecological and human health risks associated with the soil in the West Area and to aid in identifying appropriate and cost-effective remedial options for the West Area. Soil samples were collected from the surface to four feet below ground surface (bgs). The results of this investigation are presented in another report (Barr, 2003). A pre-design soil investigation was completed in January 2014 (Barr, 2014) and an additional soil characterization investigation was completed in February 2015 (Barr, 2015). The pre-design soil investigation informed soil management decisions. The additional soil characterization was completed to document soil quality at depths greater than what would be excavated as part of the remedy Record of Decision Operable Unit 5-Soils from West Area and Minnesota Pollution Control Agency Southern Lots Summary of Remedial Alternative Selection Joslyn Manufacturing & Supply Co. Site • July 2018 13 alternatives being evaluated in the FFS. Generally, TCDD-TEQ concentrations from the composite samples decreased with increasing depth. Sampling locations from the investigations conducted at the West Area are presented on Figure 6a, and historic shallow soil data from the West Area used in the risk assessment described in Section 2.7 are presented on Figure 6c and in the tables in Appendix A. As shown on Figures 6a and 6c, historical soil sampling results show significant differences in the concentrations of COCs within the sub-areas of the West Area. Figure 7 summarizes dioxin concentrations within sub-areas of OU5. Sub-areas WA-4 and WA-5 have not been significantly impacted by former operations at the Joslyn Site. Conversely, surface soils within sub-areas WA-6MID and WA-6S have been impacted. Concentrations of COCs in soil samples collected from sub-areas WA-1, WA-2, WA-3, WA-6N, WA-7, and WA-8 are generally less than those measured in wetland surface soil samples collected from sub-areas WA6-MID and WA-6S. Taken together, COC concentrations in individual West Area surface soil samples were within the following ranges: Dioxin/furan (expressed as the tetrachlorodibenzo-p-dioxin [TCDD] Toxicity Equivalency Quotient [TEQ], or TCDD-TEQ): non-detectable to 176,621 ng/kg (parts per trillion) Carcinogenic PAHs (expressed as benzo(a)pyrene equivalents [BaP]): non-detectable to 350 mg/kg (parts per million) PCP: non-detectable to 450 mg/kg (parts per million) 2.5.4.2 Soil contamination – Southern lots At the request of the MPCA, Joslyn conducted an investigation for dioxin/furans in shallow soils at the Southern Lots in 2005. The purpose of the investigation was to determine dioxin/furans concentrations in the upper four feet of soil at portions of the Southern Lots located within the 100-year flood elevation of Middle Twin Lake. Soil samples were collected from zero to four feet bgs to delineate the lateral and vertical extent of dioxin/furans contamination. The dioxin/furans concentrations reported for individual samples collected from the north parcel of the Southern Lots ranged from 7.61 ng/kg (ppt) to 772 ng/kg (ppt) reported as TCDD-TEQ. The dioxin/furans concentrations reported for individual samples collected from the south parcel of the Southern Lots ranged from 3.08 ng/kg (ppt) to 5.34 ng/kg (ppt) reported as TCDD-TEQ. The highest dioxin/furans concentration was observed in native peat underlying fill material on the north parcel of the Southern Lots. The results of the 2005 investigation of the Southern Lots are presented and discussed in more detail in another report (Barr, 2005a). Investigation locations are shown on Figure 6b. An additional investigation was completed in 2009 to (1) identify areas where soil on the north parcel could be included into the West Area remedy and (2) generate soil quality data for both the north and south parcels that could be used to prepare environmental covenants. The results of the 2009 investigation confirmed that the upper four feet of soil located within the 100-year flood elevation on the north parcel will need to be remediated as part of the OU5 remedy. Data reported for four composite soil samples collected from the south parcel confirmed that dioxin/furans are present in the native peat layer. However, the results of the 2005 sampling demonstrated dioxin/furans in shallow soils at levels below the PRGs/RGs, therefore remediation will not be required (Barr, 2009). Figure 7 summarizes dioxin concentrations within OU5. In 2004, an investigation was completed of the soils beneath the roadway to the west of the Southern Lots. The roadway investigation demonstrated that concentrations of TCDD-TEQ observed on the Southern Lots did not extend to the roadway corridor to the west of the Southern Lots. Record of Decision Operable Unit 5-Soils from West Area and Minnesota Pollution Control Agency Southern Lots Summary of Remedial Alternative Selection Joslyn Manufacturing & Supply Co. Site • July 2018 14 2.5.4.3 Potential for migration and the identification of potential exposure pathways One site-specific factor that influences the likelihood of migration and the completion of potential exposure pathways is the presence of a high proportion of natural organic soils (i.e., peat) in the wetland portions of OU5. PAHs and PCP are hydrophobic in nature and thus are relatively insoluble in water and have an affinity to adsorb to particles. Dioxins/furans have also been well documented to be both hydrophobic (extremely low water solubility) and to have a strong affinity for organic matter, such as the high organic matter present in OU5 soils. Dioxins/furans have a low potential for volatilization due to a low vapor pressure. Due to their relative insolubility and strong affinity to adsorb to soil particles, the COCs are generally immobile in soils. Therefore, the potential for migration of COCs from soil to groundwater via leaching and the volatilization of dioxins/furans from the soil to air is considered low. As noted in Section 2.5.1, the findings of recent studies conducted at Middle Twin Lake, in combination with the fact that the groundwater flow direction is away from Middle Twin Lake and towards the Joslyn Site, provide assurance that the surface water migration/exposure pathway is not complete. In addition, the groundwater exposure pathway is not complete because the groundwater pump-out system at the Joslyn Site captures and treats groundwater located underneath OU5. Furthermore, the area around the Joslyn Site is served by municipal water supply and no longer, uses private wells for drinking water. Since the potential for migration of COCs to other locations or to other media (i.e., groundwater or surface water) is low, and since there is an existing groundwater pump-out and treatment system, direct contact with contaminated soil is the current and potential future surface and/or subsurface routes of human or environmental exposure for OU5. As noted in Section 2.5.1, human exposure through direct contact with soil may occur through dermal contact with contaminated soil, incidental ingestion of contaminated soil, and/or inhalation of dust derived from contaminated soil (i.e., contaminants adsorbed onto soil particles). 2.5.5 Regulatory classification of OU5 soils The regulatory classification of OU5 soils is a critical element in evaluating and selecting an appropriate remedy. The MPCA determination regarding the classification of OU5 soils allows for two general remedial alternative scenarios: (1) excavate, consolidate, and cover; and (2) excavate for offsite treatment/disposal. 2.5.5.1 Onsite consolidate and cover The EPA’s area of contamination (AOC) policy (EPA 1996) states that consolidation and in-situ treatment of hazardous waste within the AOC does not create a new point of hazardous waste generation for purposes of RCRA. Essentially, the AOC policy allows soils to be consolidated or treated in-situ without triggering land-disposal restrictions or minimum technology requirements. Therefore, excavated soils from within OU5 can be consolidated within the AOC. The EPA equates an AOC as a discrete area of generally dispersed contamination to a RCRA unit. An AOC is a RCRA unit where contamination is contiguous and of similar nature, but not necessarily homogenous. Under this definition, the entire Joslyn Site is considered an AOC. Therefore, consolidation locations considered appropriate for OU5 soils include the West Area (Alternatives 5 and 8) and portions of the Joslyn Site located outside of the West Area where contaminated soil consolidation occurred previously (Alternatives 6 and 7). 2.5.5.2 Offsite treatment and/or disposal If soils excavated from OU5 are to be treated and/or disposed offsite (outside of the AOC), the soils must be classified for proper management under federal and state regulations. Record of Decision Operable Unit 5-Soils from West Area and Minnesota Pollution Control Agency Southern Lots Summary of Remedial Alternative Selection Joslyn Manufacturing & Supply Co. Site • July 2018 15 Approximately 40% of the OU5 soils planned for excavation contain a listed waste. According to MPCA policies, soils containing a listed waste must be managed as a hazardous wasted if they are disposed offsite. For those soils, RCRA requires that the soils be treated to meet 90% contaminant reduction capped by 10 times the universal treatment standards (10xUTS) for hazardous constituents prior to disposal in a Subtitle C landfill. The only effective and commercially available treatment alternative for these soils is incineration. Under MPCA policies, about 60% of the OU5 soils planned for excavation do not contain a listed waste. For these soils, MPCA policy for disposal of dioxin-contaminated soil in a Subtitle D landfill applies. Since these soils meet MPCA criteria (must contain less than 10,000 ng/kg TCDD-TEQ), they can be disposed of in a Subtitle D landfill. Offsite disposal of all contaminated OU5 soils was considered (Alternative 3), as well as combination offsite disposal/onsite consolidation remedies where soils that contain a listed waste are consolidated on site, and soils that do not contain a listed waste, and also meet MPCA dioxin criteria, are disposed offsite at a Subtitle D landfill (Alternatives 7 and 8). 2.5.6 Determination of principal threats The NCP establishes an expectation that EPA will use treatment to address the principal threats posed by a site whenever practicable. In general, “principal threat” wastes are those source materials that contain hazardous substances that act as a reservoir for migration of contaminants to groundwater, surface water, or air, and which cannot be contained in a reliable manner or would present a significant risk to human health or the environment should exposure occur. The soils in OU5 are a combination of low-level and principal threat waste. As discussed in Section 2.5.4.3, the mobility of the contaminants associated with OU5 soils is extremely low. However, the toxicity of the soils in sub-area WA-6 would present a significant risk to human health or the environment should exposure occur and, thus, this soil is considered a principal threat waste. 2.5.7 Wetland and floodplain impacts and mitigation The majority of the West Area is located within the 100-year floodplain of Middle Twin Lake and a significant portion is delineated wetland as described in Section 2.1 and shown on Figure 8. Wetlands within the West Area were delineated in 2012 according to United States Army Corps of Engineers methods (Barr, 2012). One wetland (Wetland 1), approximately 9.0 acres in size and locate d in the West Area and Southern Lots, was identified as part of this effort. The delineated wetland is shown on Figure 8. The terms “northern wetland” and “southern wetland” will be used in this ROD to describe those portions of the wetland located north and south of the former rail spur shown on Figure 8, although it is acknowledged that both areas are hydrologically connected. Wetland and floodplain impacts and mitigation will affect both implementability and the cost of the remedial alternatives for OU5 as described below: Substantial permitting efforts with numerous federal, state, and local regulatory agencies will be required, including coordination of their regulation and policies regarding the wetland and floodplain. Wetland restoration will be required where wetlands are disturbed (e.g., remedial alternatives requiring soil to be excavated from the West Area and the excavation to be backfilled to original grade). Record of Decision Operable Unit 5-Soils from West Area and Minnesota Pollution Control Agency Southern Lots Summary of Remedial Alternative Selection Joslyn Manufacturing & Supply Co. Site • July 2018 16 Wetland replacement will be necessary to offset permanent impacts to wetland areas (e.g., remedial alternatives where wetland will need to be filled due to creation of soil covers and/or consolidation). Floodplain mitigation, including the creation of floodplain at either an onsite or offsite location, or a request for a variance will be required if the implementation of the selected remedial alternative results in a loss of floodplain (e.g., remedial alternatives where floodplain will be filled due to creation of soil covers or consolidation). 2.6 Current and potential future land and water use 2.6.1 Land use Open space is the current land use of the West Area. The area consists of wetland and forested upland, much of which is within the 100-year frequency floodplain of Twin Lakes. Joslyn owns the West Area and maintains a fence to make the West Area inaccessible to the general public. The Southern Lots are two lots, owned by Joslyn and zoned for residential land use, located adjacent to the southern boundary of the West Area. Open space is the current land use for the Southern Lots. The West Area abuts Middle Twin Lake on the west and a residential area on the south. An active railroad track runs immediately adjacent to the West Area on the north with wetlands located north of the tracks. The redeveloped portion of the Joslyn Site adjoins the West Area to the east. The redeveloped portion of the Joslyn Site is also used for the operation and maintenance of the groundwater recovery and treatment, and DNAPL recovery and treatment systems for OU1-OU3, and the maintenance of the cover for onsite soil treatment for OU4. The surrounding land use is generally residential to the north and the south and commercial to the east. The MPCA has determined that the reasonably anticipated land use for the West Area is industrial with the possibility that the West Area will remain as open space in the future. The West Area is zoned “industrial” and is identified as open space on the City of Brooklyn Center’s Comprehensive Plan for 2030 (City of Brooklyn Center, 2010). Because much of the West Area falls below the 100-year flood level of Middle Twin Lake, it is not expected that it could ever reasonably be developed for industrial purposes. Joslyn has stated their intention is for the West Area to remain as open, undeveloped space with a perimeter fence to protect and prevent access to the general public or trespassers. The Southern Lots are zoned for residential use and are shown as residential on the City of Brooklyn Center’s Comprehensive Plan for 2030 (City of Brooklyn Center, 2010). Joslyn anticipates continued ownership of these two parcels with the use of institutional controls so that they will remain undeveloped (Barr, 2005a). 2.6.2 Groundwater and surface water use The shallow groundwater aquifer below the West Area and the Southern Lots is not used for drinking water and is not anticipated to be used for drinking water in the future. The shallow groundwater aquifer downgradient (to the east) of the West Area is undergoing remediation as a part of the groundwater pump-out system for OU1 and OU2. The potential for COCs to migrate from the OU5 contaminated soils to groundwater is extremely low; however, additional protection is provided by the fact that groundwater below OU5 contaminated soils is captured and treated by the groundwater pump-out system as described above. Record of Decision Operable Unit 5-Soils from West Area and Minnesota Pollution Control Agency Southern Lots Summary of Remedial Alternative Selection Joslyn Manufacturing & Supply Co. Site • July 2018 17 The runoff from the West Area currently drains to north and northwest to the adjacent Twin Lakes, a public recreational chain of lakes. As noted in Section 2.2.3.4, investigations at the Twin Lakes have shown that no significant migration of COCs from contaminated OU5 soils has occurred. 2.7 Summary of site risks The section provides a baseline risk assessment that estimates the risks posed by OU5 if no remedial action is taken. It establishes the basis for remedial action at OU5, identifies the contaminants and exposure pathways that need to be addressed by the remedy, and summarizes future exposure pathways and risks to human and ecological receptors in the absence of any remedial action. 2.7.1 Summary of human health risk assessment This section of the ROD summarizes the baseline human health risks at OU5 of the Joslyn Site. A comprehensive site-specific baseline risk assessment (i.e., an assessment of both the West Area and Southern Lots) was not conducted for OU5 prior to this ROD; however, a comprehensive screening-level assessment based on Minnesota and federal media-specific concentration guidelines was conducted. The results reported in this section are based on the following risk-based concentration guidelines: Chemical-specific soil and sediment PRGs developed by the MPCA using conservative exposure assumptions for residents, industrial workers, and recreational users of Middle Twin Lake; and Chemical-specific fish tissue standards developed by the EPA and based on human health risk assessment guidance. The MPCA PRGs used as screening-level risk characterization tools are based on methods and assumptions drawn from established EPA and general risk assessment guidance. Soil reference values (SRVs), which are applicable to sites where direct contact with soil is expected to take place, are chemical-specific soil concentrations above which an unacceptable risk to human health may exist. The SRVs referenced in this ROD are generic guidelines that are derived by the MPCA using a mixture of central tendency and conservative assumptions about exposure to various types of receptors (MPCA, 1999b). The sediment screening value (SSV) is a site-specific value advanced by the MDH for use at Middle Twin Lake (MPCA, 2006c). The EPA fish tissue guidance, which was reported in the Final Report of the National Study of Chemical Residues in Lake Fish Tissue, is based on regular, long-term ingestion of predator fish tissue (EPA, 2009). In addition to the application of guideline concentrations to site-specific concentrations, this section of the ROD draws on findings from a number of targeted assessments generated for OU5: A Public Health Assessment of the West Area, which did not calculate site-specific risk but catalogued the human health risk issues at the Site (MDH, 2002) A Public Health Assessment of Middle Twin Lake, which examined human health risk through fish tissue ingestion (MDH, 2006) Other communications among Joslyn, the Minnesota state agencies (MDH, MPCA, and the Minnesota Department of Natural Resources [DNR]), and other stakeholders (Barr, 2005a; Joslyn, 2004; MPCA, 2004b; 2006a; 2006b) Four steps were conducted to assess screening-level risk to future human receptors in OU5: 1.Evaluation of data and identification of the COCs (hazard identification) 2.Identification of exposure pathways of concern and potential future receptors (exposure assessment) Record of Decision Operable Unit 5-Soils from West Area and Minnesota Pollution Control Agency Southern Lots Summary of Remedial Alternative Selection Joslyn Manufacturing & Supply Co. Site • July 2018 18 3.Identification and description of COC toxicity (toxicity characterization) 4.Characterization of potential human health risks for current and future receptors (risk characterization) 2.7.1.1 Data evaluation and identification of contaminants of concern (COCs) Soil, sediment, surface water, and fish tissue samples collected and analyzed during previous investigations were used to characterize risk to future receptors in the absence of remedial action. Soil samples used for risk characterization were collected from the OU5 “accessible” zone (upper three feet at the West Area and upper four feet of the Southern Lots) and collected in accordance with MPCA- approved sampling and quality assurance project plans. As noted in Section 2.2.1, creosote and PCP were historically used as wood preservatives at the facility. The COCs associated with historical wood treatment activity at the Joslyn Site are carcinogenic polynuclear aromatic hydrocarbons (cPAHs), which are constituents of creosote; PCP; and polychlorinated dibenzo-p-dioxins/furans (dioxins), which were minor contaminants in the commercial formulation of PCP. The reported concentrations of dioxins and furans were determined using EPA Method 4425, a high- resolution gamma spectroscopy (HRGS) screening of total planar compound concentrations, which allows for an estimate of dioxin/furan concentrations, and EPA Method 8290, a high-resolution gas chromatographic analysis that can determine concentrations of individual congeners of dioxins and furans. Both methods are considered reliable tools for assessing dioxin and furan concentrations, subject to the limitations inherent with each method. Method 8290 is a screening tool that uniquely identifies individual congeners, whereas Method 4425 is a screening tool that identifies a class of compounds and provides an estimate of TCDD equivalence. In addition, Method 4425 may be adversely affected by interferences that respond similarly to target PCDDs and PCDFs (such as PCBs and PAHs), which may bias the results. Because Method 8290 selectively identifies individual congeners, this analytical methodology provides a more representative account of concentrations of target PCDDs and PCDFs. Between 1999 and 2003; both methods were used to analyze samples. The majority of the samples were analyzed by Method 4425, and approximately 10% of samples underwent conformational analysis by Method 8290. Data were evaluated following standard operating procedures (SOPs) based on the respective guidance documents published by the EPA and available at the time of analysis. Any qualifiers applied to the sample results were specified in the Quality Assurance Project Plan. TCDD-equivalencies included in the tables in this report have been calculated based on the most recent World Health Organization (WHO) toxicity equivalency factors (TEFs), published in 2005. This includes samples collected prior to the publication of the 2005 TEF values. All samples were collected using established SOPs for field sample collection and have been evaluated for usability by collecting masked duplicates and equipment blanks where applicable. In general, the data collected for this project is considered representative of OU5, subject to the qualifications applied to the associated data. Table 1 highlights the COCs in soil, sediment, and fish tissue from the various sections of OU5 and Middle Twin Lake. A risk screening was conducted using a screening level equal to one-tenth of the corresponding media-specific screening values (at the time of the screening) to identify the COCs and to identify the significant sources of COCs. Record of Decision Operable Unit 5-Soils from West Area and Minnesota Pollution Control Agency Southern Lots Summary of Remedial Alternative Selection Joslyn Manufacturing & Supply Co. Site • July 2018 19 From the risk screening presented in Table 1, OU5 can be separated into three distinct groupings of sub- areas, representing different magnitudes of COC concentrations in soil: The group that includes WA-1 through WA-3 and WA-6 through WA-8 borders the remediated Joslyn Site and has a higher concentration of site COCs than elsewhere in OU5. For surface soils in this section of the West Area, all COCs have maximum concentrations exceeding the selection cutoff, as shown in Table 1. The forested upland sub-areas (WA-4 and WA-5) bordering Middle Twin Lake to the east have substantially lower COC soil concentrations than the rest of the West Area. The Southern Lots have low surficial soil dioxin concentrations but higher underlying soil concentrations. The other COCs were not assessed on these lots, as their concentrations on the southern border of the West Area were low and not of human health concern (Barr, 2009). Surface water was not included as a significant source of COCs in Table 1. This is attributed both to the low solubility of the COCs in water and the assessment of sediment and fish tissue, which both preferentially accumulate these COCs. As such, sediment and fish tissue concentrations act as proxies for surface water contamination. Groundwater was also not included as a significant source of COCs in Table 1. This is attributed to groundwater flow direction (from lake area to the east), and the groundwater pump-out system currently in operation on the remediated portion of the Joslyn Site. 2.7.1.2 Exposure assessment In this section, the completeness of the exposure pathways are screened and assessed. All of the PRGs and guideline values used in the screening-level risk characterization for OU5 were calculated using standardized exposure assessment data and equations that are made publicly available by the authoring agency. Complete exposure pathways (sequences of events leading to receptor contact with a chemical) were defined by the following four elements: 1.A source and mechanism of release 2.A transport medium and mechanisms of migration through the medium 3.The presence or potential presence of a receptor at the exposure point 4.A route of exposure 2.7.1.2.1 Current and future land use The completeness of exposure pathways is contingent on the future land use assumptions for OU5. Details of the current and potential future land use are in Section 2.6.1. Joslyn intends to retain ownership of both the West Area and the Southern Lots and to maintain them in their current undeveloped condition as open space. However, the MPCA considers that there is the potential for future industrial use at the West Area and residential use at the Southern Lots based on the current City of Brooklyn Center zoning regulations. Therefore, the following conservative assumptions were used for purposes of the risk assessment: Industrial worker receptor for the West Area Residential receptor for the Southern Lots 2.7.1.2.2 Pathway assessment An evaluation was undertaken of all potential future exposure pathways that could connect sources at OU5 with receptors. Potential pathways were first hypothesized and evaluated for completeness using Record of Decision Operable Unit 5-Soils from West Area and Minnesota Pollution Control Agency Southern Lots Summary of Remedial Alternative Selection Joslyn Manufacturing & Supply Co. Site • July 2018 20 the four criteria listed in Section 2.7.1.2. The pathways examined represent potential future exposure pathways in the absence of OU5 cleanup. The incomplete exposure pathways that were excluded from consideration include ingestion of, dermal absorption from, and vapor inhalation from direct exposure to groundwater. As described in Section 0, the groundwater flows from the Middle Twin Lake area to the east. In addition, a pump-out system is currently in operation at the Joslyn Site. The present/future exposure pathway involving trespassers who gain access to OU5 has also been excluded from consideration because the exposure to such trespassers would be significantly less than that to workers or recreational users, who were included in the analysis. Therefore, any remedy that minimizes risk to those receptors would also protect trespassers. Direct exposure of receptors to surface water is not assessed explicitly but is represented by proxy. Both fish tissue and sediment concentrations are indicators of contamination of site surface water as they both preferentially accumulate hydrophobic compounds, such as the OU5 COCs. Therefore, exposure to these media acts as a conservative proxy for direct exposure to surface water. The potentially complete exposure pathways are shown in Table 2 and are visually summarized in the CSM (Figure 3). In the SRV and SSV screening-level risk methodology, human exposure to COCs through each of the pathways shown in Table 2 is implicitly calculated using a mixture of central tendency and conservative assumptions. The objective is the calculation of the reasonable maximum exposure (RME) for each receptor class. The RME represents a high-end (conservative) exposure that could reasonably be expected to occur in a population. The RME-based equations used to calculate chemical-specific SRVs for soil are documented in the “Risk-Based Guidance for the Soil Human Health Pathway, Volume 2: Technical Support Document” (MPCA, 1999b). For each of the COCs assessed, incidental ingestion of site soil is the driving exposure pathway in the calculation of the SRV. The RME-based equations used to calculate the dioxin recreational exposure SSV can be found in two memoranda from the MDH to the MPCA regarding the derivation of site-specific sediment screening levels (MPCA, 2006a; 2006b). Dermal absorption from contact with sediment during recreational use of the lake represents over half of the estimated dioxin exposure in the calculation of this site-specific SSV. Exposure to media-specific concentrations at or above the SRV/SSV does not necessarily mean that the effective lifetime risk to receptors at this particular site would exceed the state guideline value of 1 in 100,000 lifetime excess cancer risk. It does mean, however, that in the absence of remedial action, a site-specific risk assessment would be conducted to establish a level of risk lower than the target guideline. 2.7.1.3 Toxicity assessment The COCs identified as potential drivers of risk in OU5 all are regulated as carcinogens. However, the only specific compound within the list of OU5 COCs that the EPA has unequivocally judged to be a human carcinogen is 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). The COCs and a brief summary of their carcinogenicity are detailed in Table 3. The carcinogenicity of mixtures of dioxins is established by the use of TEFs, which normalize the carcinogenicity of each dioxin to that of the reference compound, TCDD. Once the TEFs are applied to media concentrations, they can be summed to establish the TCDD Toxic Equivalent concentration (TCDD-TEQ). The TEF scheme used to characterize dioxin concentrations in this assessment is the WHO 2005 dioxins/furans weighting scheme. The same has been done with PAHs, using an MDH weighting Record of Decision Operable Unit 5-Soils from West Area and Minnesota Pollution Control Agency Southern Lots Summary of Remedial Alternative Selection Joslyn Manufacturing & Supply Co. Site • July 2018 21 scheme based on that used by the California EPA to normalize the carcinogenicity of these compounds. Concentrations of PAHs are thus expressed as BaP equivalents. Dioxins and PCP also demonstrate non-cancer toxicity over chronic exposure periods. Dioxins are known to cause effects on immune function, reproduction and development, diabetes, thyroid function, and lipid levels in both animals and humans (EPA, 2003). The EPA’s Integrated Risk Information System (IRIS) documents only one chronic feeding study for PCP, which found that the compounds causes pigmentation in the liver and kidneys of male and female rats. Despite this, non-cancer impacts are only evident at substantially higher levels of chronic exposure than lifetime cancer risk for both dioxins and PCP. For PCP, the state cancer guideline is reached at a chronic daily exposure 125 times lower than that needed to reach the non-cancer guideline for an RME industrial worker receptor, and 80 times lower for an RME residential or recreational receptor. As a consequence, non-cancer risk is not used in the development of the SRVs/SSV. 2.7.1.4 Risk characterization Risk characterization is defined as the process by which the nature and magnitude of potential human health risks and the associated uncertainty are assessed. The risk characterization for OU5 is based on the screening-level risk assessment methodologies developed by the MPCA and EPA and represented by the SRV and SSV PRGs and national fish tissue guidelines. Rather than explicitly characterizing the lifetime excess cancer risk to receptors by combining chronic levels of exposure with toxicity information in the form of a dose-response curve, this method compares medium-specific guideline concentrations to site concentrations in order to identify the COCs and sub-areas of the site that may pose future risks to specific receptor types. The guideline concentrations used in this risk assessment were generated using the assumption of RME receptors and are based on generally accepted guidance for exposure and risk assessment. The MPCA generated the SRVs and SSV by setting the risk to the state cancer guideline of 1 in 100,000, or 1 x 10-5, excess cancer cases. Risks above this level are generally deemed unacceptable by the state and require remediation. The EPA also generated their fish tissue dioxin guidance by setting the risk level to 1 in 100,000, or 1 x 10-5, excess cancer cases (EPA, 2000). The Tier 1 (resident) and Tier 2 (industrial worker and recreational user) SRVs were developed for generalized use by the MPCA, and as such are not site-specific. Calculation of these guideline soil concentrations combines three exposure pathways: incidental soil ingestion, inhalation of COC vapor, and dermal exposure. As stated in Section 2.7.1.2, incidental soil ingestion is the driving exposure pathway for all three COCs. The EPA fish tissue guideline concentration for dioxins was also meant for broad, screening-level application to ingestion of predator fish tissue. The SSV for dioxins, on the other hand, was developed for a site-specific assessment of sediment on the east side of Middle Twin Lake (MPCA, 2006a; 2006b). The results of the screening-level risk characterization for COCs are given in Table 4. The results demonstrate the varying soil conditions across OU5. The WA-4 and WA-5 sub-areas have a low level of dioxin contamination, straddling the MPCA’s industrial SRV. Alternatively, the other sub-areas within the West Area show relatively higher levels of dioxin and PAH contamination, well above their respective industrial SRVs for a number of samples. Sampling from the Southern Lots shows dioxin concentrations that exceed the residential SRV; however, the samples are composites of underlying peat, which is both a large sink for dioxins as well as an immobilizer for these compounds. The results in Table 4 and on Figures 6c and 7 confirm that dioxins are the driver for human health risk in areas where there are substantial exceedances of SRVs (i.e., in the WA-1 to WA-3 and WA-6 to WA-8 cluster of sub-areas as well as on the Southern Lots). Any remedy that addressed dioxin concentrations Record of Decision Operable Unit 5-Soils from West Area and Minnesota Pollution Control Agency Southern Lots Summary of Remedial Alternative Selection Joslyn Manufacturing & Supply Co. Site • July 2018 22 would also address other COCs; therefore, analysis of human health risk of the other COCs is not necessary. Industrial worker exposure to soils in the WA-4 and WA-5 sub-areas as characterized by MPCA’s industrial SRV is not suggestive of risk beyond the state guideline of 1 in 100,000. The one composite sample from the WA-5 sub-area is slightly higher than the 35 parts per trillion (ppt) SRV for dioxins. However, there are a number of reasons that the dioxin concentration of the composite sample is not suggestive of excess risk to workers in this area. The SRV was calculated using assumptions of RME receptors and soils that are generally lower in organic content than those found at OU5; thus, some of the parameters used over-estimate the exposure and consequent risk to a typical worker. These parameters include job tenure of 25 years, and absorption of dioxins in the gut from incidentally ingested soil of 55%. The job tenure assumption represents the 95th percentile occupational tenure without regard to the type of job and location in which the job is done (e.g., outdoor construction, office work). This implies that only 5% of all workers will have job tenure at least as long as this. The proportion of dioxins absorbed in the gut is based on the proportion of TCDD absorbed from dietary sources in humans versus laboratory animals used to test the toxicity of TCDD. Absorption from ingested soil is thought to range widely as a function of soil organic content, aging, and other factors (Van den Berg et al., 2005). The experimentally determined range of bioavailabilities is from 0.5% to 43% (EPA, 2003). The MPCA’s RME SRV assumes 30% bioavailability (MPCA, 1999b). Dioxins in soils with high organic content like the soil in this site sub-area typically show very low bioavailability. As a result of these and other considerations, the WA-5 soil does not pose an unacceptable health risk. The sediment samples from the eastern shore of Middle Twin Lake have dioxin concentrations well below the PRG as represented by the site-specific SSV. Accordingly, the risk to a future recreational user of Middle Twin Lake is below the state target of 1 in 100,000. The fish tissue dioxin concentrations found in Middle Twin Lake fall below the EPA fish tissue guideline concentration of 0.15 ppt in predator fish tissue—a standard developed using an exposure assumption of one eight-ounce fish meal per week over a 70-year lifetime. The median concentration of dioxin found in northern pike tissue from the lake is approximately an order of magnitude below this guideline value (Barr, 2006b). The MDH found in their Health Consultation for Middle Twin Lake that human health risk from fish ingestion was controlled by exposure to mercury and PCB—chemicals not associated with past site activity—and not dioxins (MDH, 2006). Recently, new fish consumption guidance was released by the MDH for Middle Twin Lake (DNR, 2009). Similar to past guidance, the northern pike consumption advisories for Middle Twin Lake are based on tissue mercury concentrations (DNR, 2009). These advisories suggest limiting intake to one eight-ounce meal per week for the general population, and one eight-ounce meal per week of less than 24-inch long fish and one eight-ounce meal per month of greater than 24-inch long fish for pregnant women. Given the relatively low levels of dioxin detected in northern pike tissue, these recommendations are protective for dioxin-specific lifetime cancer risk. The 2009, fish consumption guidance also indicated that the fluorosurfactant and emerging industrial contaminant perfluorooctane sulfonate (PFOS) now drives risk from the ingestion of panfish and largemouth bass. The release of PFOS, which has been found in fish tissue in a number of lakes in the Twin Cities (MDH, 2009), is not connected with past activity at the site. Taken in combination, the fish tissue and sediment findings at the WA-5 sub-area confirm that COC concentrations in Middle Twin Lake have been very slightly affected, if at all, by proximity to OU5. The potential connection from the southern wetland to the northern wetland and then to Middle Twin Lake Record of Decision Operable Unit 5-Soils from West Area and Minnesota Pollution Control Agency Southern Lots Summary of Remedial Alternative Selection Joslyn Manufacturing & Supply Co. Site • July 2018 23 via the former ice chute appears to be a small to negligible source of COCs for the lake. The hydrophobic nature of the COCs and presence of soils with high organic content likely prevent significant site mobilization. Additionally, the preferential flow of groundwater to the east and southeast towards the groundwater pump-out minimizes shallow groundwater infiltration into the lake. In general, direct exposure to surface water is considered an incomplete exposure pathway and consequently is determined not to be a human health concern. The soil dioxin concentrations in the Southern Lots may be indicative of future risk to human health; however, the issue is complicated by the dioxin concentration gradient seen in sampling. Dioxin concentrations in the surficial soils (0 – 0.5 feet in depth) meet MPCA’s residential SRV of 20 ppt, while dioxin concentrations in deeper samples (0.5 – 4 feet in depth) exceed the SRV. The likelihood of future exposure to soil deeper than 0.5 feet is low in the absence of construction activity. Additionally, though these lots are zoned residential by the City of Brooklyn Center, they are unlikely to be developed into residences in the future due to their location within the 100-year floodplain of Middle Twin Lake. As such, there is a low probability of future exposure of the underlying soils from construction activity, and institutional controls would likely be sufficient to prevent the emergence of any exposure pathways. However, the MPCA conservatively determined that “accessible” soils in the Southern Lots should be defined as the upper four feet of the final grade (MPCA, 2005b), thus categorizing the soil in the Southern Lots as non-conforming. 2.7.1.5 Human health risk assessment conclusions Risk from direct exposure to soils containing elevated concentrations of dioxins/furans is the driver of remedial action in OU5. These soils have not been and are not anticipated to be sources for migration of COCs into other media such as surface water, sediment, or fish tissue. Excavation or isolation of these soils would interrupt the potential for direct receptor contact and consequent risk. Industrial worker screening-level cancer risk from direct exposure to soil exceeds the Minnesota guideline of 1 in 100,000 excess cases for the WA-1 to WA-3 and WA-6 to WA-8 sub-areas within the West Area. This is driven primarily by dioxin soil concentrations, and not by cPAHs or PCP. Though the industrial worker SRV utilizes a generally conservative approach to the characterization of risk, the dioxin concentrations in these areas are substantially elevated above the SRV and above EPA’s higher interim PRG for industrial worker receptors of 950 ppt. Therefore, a remedial action in this portion of the West Area is required. The remedial action alternatives considered were evaluated based on their ability to eliminate or significantly reduce this exposure pathway for future workers. Industrial worker screening-level cancer risk from direct exposure to soil slightly exceeds the Minnesota guideline of 1 in 100,000 excess cases for the WA-5 sub-area within the West Area. This is not anticipated to translate into effective future risk above this guideline because of the generally conservative exposure factor assumptions used to characterize the risk to a typical worker, including job tenure and percent of dioxins absorbed in the gut from soils. Accordingly, the human health risk from exposure to soil in this area is likely to be low and does not require action. For the Southern Lots, resident screening-level cancer risk from direct exposure to dioxin-containing soils would be considered to exceed the Minnesota guideline of 1 in 100,000 excess lifetime cancer risk. However, the TCDD-TEQ concentrations in the surficial samples of these lots are well below the residential SRV. In addition, there is a very low to negligible likelihood that these lots will be developed residentially because half of their area is below the 100-year flood elevation of Middle Twin Lake, and Joslyn’s intent to maintain ownership of the lots. However, “accessible” soils, as currently defined, are Record of Decision Operable Unit 5-Soils from West Area and Minnesota Pollution Control Agency Southern Lots Summary of Remedial Alternative Selection Joslyn Manufacturing & Supply Co. Site • July 2018 24 non-conforming. Accordingly, the human health risk from exposure to soil in this area is low but uncertain. Other risks examined here are anticipated to be substantially lower than the state cancer guideline and do not require further action. 2.7.1.6 Uncertainty characterization Uncertainty exists in the characterization of risk to receptors from exposure to COCs in OU5. Some contributors to human health risk uncertainty (and indicators of their impact on overall uncertainty) include: Sampling and analytical methods (low-medium impact) Sample location/sample size for each medium (low-medium impact) Assumption of constant COC concentration over time (low impact) Use of generic guideline values for the characterization of risk (medium-high impact) Use of industrial worker receptor to characterize risk at West Area and resident receptor to characterize risk on the Southern Lots (medium-high impact) Given the uncertainties associated with the human health risk assessment and the purposeful bias towards risk over-estimation in a screening-level analysis, it is expected that the identification of areas where cancer risk from direct exposure to soil exceeds the state guideline of 1 in 100,000 is more inclusive than a site-specific risk assessment might identify. 2.7.2 Summary of ecological risk assessment The ecological PRGs for the West Area were developed from sediment quality criteria from multiple sources (CCME, 2002; Crane et al., 2000) and are shown in Table 5. Because a significant portion of the West Area falls below the OHWL, the MPCA determined that separate terrestrial PRGs were not needed (MPCA, 2005a). These criteria extend to the Southern Lots, of which a significant proportion of the surface area falls below the OHWL. Therefore, the ecological PRGs can be applied to soil and sediment across OU5. 2.7.3 Basis for the response action Risk from direct exposure to soils containing elevated concentrations of dioxins/furans is the basis for remedial action in OU5. The OU5 response action selected in this ROD is necessary to protect the public health or welfare or the environment from actual or threatened releases of hazardous substances into the environment. 2.8 Remedial action objectives Remedial action objectives (RAOs) for OU5 of the Joslyn Site were developed based on a review of investigation data; site-specific risk and fate/transport evaluations; applicable, or relevant, and appropriate requirements (ARARs); and to be considered (TBC) requirements. The primary COC for OU5 is dioxin/furans. The selected remediation goals (RGs) for human and ecological receptors for OU5 are the same as the previously determined PRGs, and are shown in Table 5. The RGs selected for surface soil is 35 ppt for the West Area and 20 ppt for the Southern Lots. The RGs were selected based on SRVs established by MPCA that are protective for use by industrial workers for the West Area and protective for residential use for the Southern Lots. This conforms to the current Record of Decision Operable Unit 5-Soils from West Area and Minnesota Pollution Control Agency Southern Lots Summary of Remedial Alternative Selection Joslyn Manufacturing & Supply Co. Site • July 2018 25 zoning designation of these areas; however, the areas are planned to remain as open space for the future. The RG for sediment in Middle Twin Lake is 50 ppt based on SRVs and for aquatic/terrestrial ecological receptors, the RG is 11.2 ppt based on Aquatic sediment quality values. The RAOs specifically developed for OU5 of the Joslyn Site are as follows: Prevent incidental ingestion and direct contact with surface soils that contain concentrations of COCs above the soil cleanup goals noted in Table 5. Control future releases of contaminants to ensure protection of human health and the environment. 2.9 Description of alternatives Eight alternatives for remediating OU5 soils were evaluated in the FFS (Barr, 2013). Below are summaries and brief descriptions of the alternatives evaluated in the FFS. Also provided for each alternative are capital costs, O&M costs, and present worth cost. Present worth cost was developed using an O&M period of 30 years. Detailed descriptions, figures, and cost estimate tables for each alternative can be found in the FFS. A number of alternatives listed below include excavating and/or covering soils; the excavation depths vary based on a comparison of existing soil quality data to the human health and ecological screening values for each of the sub-areas within OU5. 2.9.1 Alternative 1 – No action The NCP requires that a no action alternative be evaluated as part of the screening process, in order to provide a baseline for comparison to other alternatives. Under this alternative, no further actions would be taken to address the soils in OU5 of the Joslyn Site. Costs shown are for fence maintenance, inspection, monitoring and reporting. Estimated Capital Cost: $ 0 Estimated O&M Cost: $ 530,000 Estimated Present Worth Cost: $ 530,000 Estimated Implementation Time: On going 2.9.2 Alternative 2 – Stormwater management modifications Modification of the current path of stormwater flow adjacent to and through OU5 can aid in meeting the RAO of removing the ongoing threat of COC transport to Middle Twin Lake. This section describes the existing stormwater management system at the Joslyn Site, as well as a conceptual plan for both interim and permanent stormwater management that has been developed as either a stand-alone remedial alternative or for use in conjunction with Alternatives 3 through 5. There are currently three different potential stormwater inflows to the West Area from detention ponds located on the developed portion of the Joslyn Site. Surface water in the West Area drains via two pathways into Middle Twin Lake: through the former ice chute located in the northern portion of the West Area or via the diffuse connection through the emergent vegetation in the northwestern portion of the West Area (northwest of the northern wetland). The wetland located in the southern portion of Record of Decision Operable Unit 5-Soils from West Area and Minnesota Pollution Control Agency Southern Lots Summary of Remedial Alternative Selection Joslyn Manufacturing & Supply Co. Site • July 2018 26 the West Area (the southern wetland) does not currently have a direct pathway for stormwater flow to Middle Twin Lake; it must overflow into the northern wetland prior to discharging to the lake. The conceptual stormwater management plan is designed to redirect runoff during implementation of the Selected Remedy, with the reintroduction of flow to the northern wetland of the West Area following site restoration activities. This would be accomplished through a combination of construction of stormwater treatment best management practices, new storm sewers, and temporary sheet piling. Estimated Capital Cost: $ 1,700,000 Estimated O&M Cost: $ 624,000 Estimated Present worth Cost: $ 2,320,000 Estimated Implementation Time: Less than 1 year 2.9.3 Alternative 3 – Excavation for offsite treatment and disposal This alternative combines the stormwater management modifications of Alternative 2 with the excavation of one to four feet of contaminated soil from OU5. The depth of soil excavation will vary by sub-area. It was conservatively assumed that soils would not be segregated during excavation and that all excavated soils would require treatment by incineration at a permitted hazardous waste incinerator followed by disposal of incineration residuals at a Subtitle C landfill. This alternative includes the following primary components: Removal and disposal of vegetation, including brush and trees Temporary and permanent stormwater management Excavation and load-out of contaminated soil (35,000 cubic yards or approximately 49,000 tons) Placement of non-woven geotextile in excavated areas and subsequent backfill with clean soil as required (24,000 cubic yards of soil) Transportation, treatment, and disposal of excavated soil (35,000 cubic yards or approximately 49,000 tons) Wetland mitigation (on site or off site as needed) Site restoration – planting and establishing vegetation Post-construction maintenance and monitoring Placement of institutional controls This alternative may require excavating soil below the water table in some locations. The excavated soil will be dewatered as necessary and then transported via trucks with covered beds to a staging facility for transfer into bulk transport vehicles (likely gondola rail cars) and transport to a permitted hazardous waste incinerator. Since there would be minimal net change in existing grade, no significant floodplain mitigation would be required as part of this remedial alternative. Although the existing wetlands in OU5 would be restored following the excavation and backfill undertaken as part of this alternative, additional wetland mitigation may be required by the applicable regulatory agencies. Institutional controls would be put in place to restrict future land use as necessary. Long-term inspections of the stormwater management system, surface soil erosion, and wetland vegetation monitoring and maintenance would be required. This alternative can be implemented only if the excavated soil can be accepted at an offsite location for treatment and/or disposal in accordance with the applicable rules for waste disposal. Record of Decision Operable Unit 5-Soils from West Area and Minnesota Pollution Control Agency Southern Lots Summary of Remedial Alternative Selection Joslyn Manufacturing & Supply Co. Site • July 2018 27 Estimated Capital Cost: $ 67,350,000 Estimated O&M Cost: $ 624,000 Estimated Present worth Cost: $ 67,970,000 Estimated Implementation Time: Less than 1 year 2.9.4 Alternative 4 – In-place soil cover This alternative involves combining the stormwater management modifications of Alternative 2 with the placement of two feet of clean cover over the entire West Area. Contaminated soils excavated from the Southern Lots and other areas as part of stormwater management modifications would be consolidated into the West Area prior to capping. The West Area cap would consist of a non-woven geotextile fabric overlaid with 1.5 feet of clean cover soil and 0.5 feet of topsoil. The primary work tasks needed to cap contaminated soils with a vegetated soil cover include the following: Removal and disposal of vegetation, including brush and trees Temporary and permanent stormwater management Excavation and consolidation of contaminated soils from the Southern Lots and other areas required for stormwater management modifications into the West Area (3,000 cubic yards) Placement of a non-woven geotextile prior to clean cover soil placement (19,000 cubic yards of cover soil) Floodplain and wetland mitigation (off site as needed and/or available) Site restoration – planting and establishing vegetation Post-construction maintenance and monitoring This alternative would require both floodplain and wetland mitigation for that lost through the placement of the soil cover. If sufficient mitigation could not be obtained to offset the net volume of floodplain filled as part of this alternative, a variance would be required. Estimated Capital Cost: $ 14,590,000 Estimated O&M Cost: $ 624,000 Estimated Present worth Cost: $ 15,210,000 Estimated Implementation Time: Less than 1 year 2.9.5 Alternative 5 – Onsite consolidation with soil cover at West Area This alternative involves combining the stormwater management modifications of Alternative 2 with the excavation of contaminated soil from the north portion of the West Area and from the Southern Lots for onsite placement and management. The excavated materials would be placed into an onsite consolidation area constructed over the contaminated soil that remains in place in the southern part of the West Area. A small strip of land south of the consolidation area and north of the Southern lots would also be excavated and consolidated. This onsite consolidation area would be capped with a vegetative soil cover. The cap will consist of a non-woven geotextile fabric overlaid with 1.5 feet of clean cover soil and 0.5 feet of topsoil. Record of Decision Operable Unit 5-Soils from West Area and Minnesota Pollution Control Agency Southern Lots Summary of Remedial Alternative Selection Joslyn Manufacturing & Supply Co. Site • July 2018 28 The scope of work for this alternative includes the following tasks: Removal and disposal of vegetation, including brush and trees Temporary and permanent stormwater management Excavation of contaminated soils and placement within the consolidation area (22,000 cubic yards) Placement of a non-woven geotextile prior to clean cover soil placement at the onsite consolidation area (6,000 cubic yards of cover soil) Placement of non-woven geotextile in excavated areas and subsequent backfill with clean soil as required (12,000 cubic yards of soil) Floodplain and wetland mitigation (on site and/or off site as needed and/or available) Site restoration – planting and establishing vegetation Post-construction maintenance and monitoring This alternative would require mitigation for both the Middle Twin Lake floodplain and wetlands that would be lost through the construction of the onsite consolidation area. Estimated Capital Cost: $ 4,330,000 Estimated O&M Cost: $ 624,000 Estimated Present worth Cost: $ 4,950,000 Estimated Implementation Time: Less than 1 year 2.9.6 Alternative 6 – Onsite consolidation with soil cover at Azelia Avenue Pond This alternative consists of the excavation of contaminated soil from OU5 and the consolidation of the contaminated soils east of Building 1 within the Joslyn Site. Consolidation would be done at the current location of a stormwater pond (known as the Azelia Avenue Pond) and adjacent to a contaminated soil consolidation area used during redevelopment of the Joslyn Site (Geomatrix, 2001 and 2002). Excavation of contaminated soils at OU5 would proceed similarly to that proposed for Alternative 3. The depth of soil excavation would vary by sub-area. The stormwater management modifications for Alternative 6 vary from Alternatives 2 through 5 as an existing stormwater pond would be filled with soils excavated from OU5 as part of this alternative. Stormwater management modifications for this alternative are significant and include the construction of a new stormwater pond with retaining walls at the south swale. The excavated soils would be consolidated at the location of the current Azelia Avenue Pond, filling in the pond and creating an aboveground consolidation area that abuts the existing contaminated soil consolidation area located north of the pond. This consolidation area would be capped with a vegetative soil cover that consists of a non-woven geotextile overlaid with 1.5 feet of clean cover soil and 0.5 feet of topsoil. Several modifications to existing monitoring and pump-out wells located within or near the proposed consolidation area would need to be completed under this alternative. Two monitoring wells (W300SPN and W7) would require abandonment and replacement, and the well casings of one monitoring well (W254) and two pump-out wells (U4 and U5) would need to be extended. The scope of work for this alternative includes the following primary tasks: Removal and disposal of vegetation, including brush and trees Record of Decision Operable Unit 5-Soils from West Area and Minnesota Pollution Control Agency Southern Lots Summary of Remedial Alternative Selection Joslyn Manufacturing & Supply Co. Site • July 2018 29 Temporary and permanent stormwater management Excavation of contaminated soils and placement within the consolidation area (35,000 cubic yards or approximately 49,000 tons) Modifications to existing groundwater pump-out system Placement of a non-woven geotextile prior to clean cover soil placement at the onsite consolidation area y (6,000 cubic yards of cover soil) Placement of non-woven geotextile in excavated areas and subsequent backfill with clean soil to original grade as required (27,000 cubic yards of backfill soil) Wetland mitigation (on site or off site as needed) Site restoration – planting and establishing vegetation Post-construction maintenance and monitoring Because there would be minimal net change in existing grade within OU5, it is anticipated that no significant floodplain mitigation would be required as part of this remedial alternative. The need for floodplain mitigation would be determined during final design. Although the existing wetlands in OU5 would be restored following the excavation and backfill undertaken as part of this alternative, additional wetland mitigation may be required by the applicable regulatory agencies. Estimated Capital Cost: $ 4,740,000 Estimated O&M Cost: $ 1,131,000 Estimated Present worth Cost: $ 5,870,000 Estimated Implementation Time: Less than 1 year 2.9.7 Alternative 7 – Onsite consolidation with soil cover at Building 1A Pond Alternative 7 consists of the excavation of contaminated soil from OU5 and the consolidation of a portion of the excavated soils at a designated location north of Building 1 within the Joslyn Site and disposal of a portion of the excavated soils off site in a Subtitle D landfill. The proposed consolidation site is the current location of the stormwater pond known as the Building 1A Pond, directly adjacent to the West Area. Excavation of contaminated soil at OU5 would proceed similarly to that proposed for Alternative 3 of the FFS, with the depths of soil excavation varying by sub-area. Excavated soils would either be transported off site to a Subtitle D landfill as described in Section 2.5.5.2, or they would be consolidated in the location of the current Building 1A Pond, filling in the pond and creating an aboveground consolidation area. This consolidation area would be capped with a vegetative soil cover that consists of a non-woven geotextile overlaid with 1.5 feet of clean cover soil and 0.5 feet of topsoil. Stormwater management modifications for this alternative are significant and include modifications to the Azelia Avenue Pond to replace the functions of the filled Building 1A Pond. An existing monitoring well (W2N) located in the vicinity of the Building 1A Pond would need to be abandoned under this alternative. The scope of work for this alternative is assumed to include the following primary tasks: Removal and disposal of vegetation, including brush and trees Temporary and permanent stormwater management Excavation of contaminated soils (35,000 cubic yards) Record of Decision Operable Unit 5-Soils from West Area and Minnesota Pollution Control Agency Southern Lots Summary of Remedial Alternative Selection Joslyn Manufacturing & Supply Co. Site • July 2018 30 Placement of selected excavated soils within the consolidation area (15,000 cubic yards) Transportation and disposal of selected excavated soil at a Subtitle D landfill (20,000 cubic yards or approximately 27,000 tons) Abandonment of an existing monitoring well Placement of a non-woven geotextile prior to clean cover soil placement at the consolidation area (5,000 cubic yards of cover soil) Placement of non-woven geotextile in excavated areas and subsequent backfill with clean soil as required (26,000 cubic yards of soil) Floodplain and wetland mitigation Site restoration – planting and establishing vegetation Post-construction maintenance and monitoring Alternative 7 would require mitigation for floodplain and wetlands that will be lost through construction of the onsite consolidation area and for stormwater management modifications. Estimated Capital Cost: $ 4,600,000 Estimated O&M Cost: $ 780,000 Estimated Present worth Cost: $ 5,380,000 Estimated Implementation Time: Less than 1 year 2.9.8 Alternative 8 – Limited onsite consolidation with soil cover at West Area Alternative 8 consists of the excavation of contaminated soil from OU5 and the consolidation of a portion of the excavated soils within an onsite consolidation area (constructed over contaminated soil that remains in place in the southern part of the West Area) and disposal of a portion of the OU5 soils off site in a Subtitle D Landfill. Excavation of contaminated soil at OU5 would proceed similarly to that proposed for Alternative 3 of the FFS, with the depths of excavation for contaminated soils located outside of the consolidation area footprint varying by sub-area. The excavated soils would either be transported off site to a Subtitle D landfill as described in Section 2.5.5.2, or they would be consolidated in the southern part of the West Area. This consolidation area would be capped with a vegetative soil cover that consists of a non-woven geotextile overlaid with 1.5 feet of clean cover soil and 0.5 feet of topsoil. The scope of work for this alternative is assumed to include the following primary tasks: Removal and disposal of vegetation including brush and trees Temporary and permanent stormwater management Excavation of contaminated soils (30,000 cubic yards) Placement of selected excavated soils within the consolidation area (10,000 cubic yards) Transportation and disposal of selected excavated soil at a Subtitle D landfill (20,000 cubic yards or approximately 27,000 tons) Placement of a non-woven geotextile prior to clean cover soil placement at the consolidation area (4,000 cubic yards of cover soil) Placement of non-woven geotextile in excavated areas and subsequent backfill with clean soil as required (28,000 cubic yards of soil) Floodplain and wetland mitigation Record of Decision Operable Unit 5-Soils from West Area and Minnesota Pollution Control Agency Southern Lots Summary of Remedial Alternative Selection Joslyn Manufacturing & Supply Co. Site • July 2018 31 Site restoration – planting and establishing vegetation Post-construction maintenance and monitoring Alternative 8 would require mitigation for floodplain and wetlands that would be lost through construction of the onsite consolidation area and stormwater management modifications. Two options for obtaining the floodplain mitigation necessary to implement Alternative 8 were evaluated. The first option was to create additional floodplain at an offsite location (Alternative 8A) and the second option was to create additional floodplain within the West Area and the Southern Lots (Alternative 8B). Costs for each Alternative 8 floodplain mitigation option are shown below. Alternative 8A – Offsite floodplain mitigation Estimated Capital Cost: $ 4,730,000 Estimated O&M Cost: $ 624,000 Estimated Present worth Cost: $ 5,350,000 Estimated Implementation Time: Less than 1 year Alternative 8B – Onsite floodplain mitigation Estimated Capital Cost: $ 4,160,000 Estimated O&M Cost: $ 624,000 Estimated Present worth Cost: $ 4,780,000 Estimated Implementation Time: Less than 1 year 2.10 Comparative analysis of alternatives This section of the ROD provides the basis for the determining which alternative provides the best balance with respect to the statutory balancing criteria in Section 121 of CERCLA and in Section 300.430 of the NCP. The remedial alternatives selected from the screening process were evaluated using the following nine criteria: Overall protection of human health and the environment Compliance with applicable and/or relevant and appropriate Federal and State public health or environmental standards (ARARs) Long-term effectiveness and permanence Reduction of toxicity, mobility, or volume of hazardous substances through treatment Short-term effectiveness Implementability Cost-effectiveness Acceptance by support agency (EPA) Acceptance by Community The NCP categorizes the nine criteria into three groups: 1.Threshold criteria – overall protection of human health and the environment and compliance with ARARs (or invoking a waiver) are threshold criteria that must be satisfied in order for an alternative to be eligible for selection. Record of Decision Operable Unit 5-Soils from West Area and Minnesota Pollution Control Agency Southern Lots Summary of Remedial Alternative Selection Joslyn Manufacturing & Supply Co. Site • July 2018 32 2.Primary balancing criteria – long-term effectiveness and permanence; reduction of toxicity, mobility, or volume; short-term effectiveness; implementability; and cost are primary balancing factors used to weigh major trade-offs among alternatives. 3.Modifying criteria – state and community acceptances are modifying criteria that are formally taken into account after public comment is received on the Proposed Plan and incorporated into the ROD. Two additional criteria were used to evaluate the remedial alternatives: Principal threat waste considerations Floodplain and wetland mitigation 2.10.1 Threshold criteria 2.10.1.1 Overall protection of human health and the environment Overall protection of human health and the environment addresses whether each alternative provides adequate protection of human health and the environment and describes how risks posed through each exposure pathway are eliminated, reduced, or controlled through treatment, engineering controls, and/or institutional controls. All of the alternatives except Alternative 1 and Alternative 2 are protective of human health and the environment by reducing or eliminating exposure pathways. Alternative 1 and Alternative 2 (as stand-alone alternatives) are therefore removed from further consideration. 2.10.1.2 Compliance with ARARs Section 121(d) of CERCLA and NCP §300.430(f)(1)(ii)(B) require that remedial actions at CERCLA sites at least attain legally applicable or relevant and appropriate Federal and State requirements, standards, criteria, and limitations, which are collectively referred to as “ARARs,” unless such ARARs are waived under CERCLA Section 121(d)(4). 2.10.1.2.1 Definition of ARARs and TBCs Applicable requirements are those cleanup standards, standards of control, and other substantive requirements, criteria, or limitations promulgated under Federal environmental or State environmental or facility siting laws that specifically address a hazardous substance, pollutant, contaminant, remedial action, location, or other circumstance found at a CERCLA site. State standards that are identified by a state in a timely manner and that are more stringent than Federal requirements may be applicable. Relevant and appropriate requirements are those cleanup standards, standards of control, and other substantive requirements, criteria, or limitations promulgated under Federal environmental or State environmental or facility siting laws that, while not “applicable” to a hazardous substance, pollutant, contaminant, remedial action, location, or other circumstance at a CERCLA site, address problems or situations sufficiently similar to those encountered at the CERCLA site that their use is well-suited to the particular site. Only those state standards that are identified in a timely manner and are more stringent than federal requirements may be relevant and appropriate. TBCs are criteria, advisories, guidance, and proposed standards developed by government agencies that are not legally enforceable but contain information that would be helpful in carrying out, or in determining the level of protectiveness of, selected remedies. TBCs are meant to complement the use of ARARs, not replace or compete with them. Record of Decision Operable Unit 5-Soils from West Area and Minnesota Pollution Control Agency Southern Lots Summary of Remedial Alternative Selection Joslyn Manufacturing & Supply Co. Site • July 2018 33 Compliance with ARARs addresses whether a remedy will meet all of the applicable or relevant and appropriate requirements of other Federal and State environmental statutes or provides a basis for a invoking a waiver of specific ARARs. Tables 6-1 through 6-5 summarize the federal and state ARARs and TBCs compiled for this project and if/when, they apply. 2.10.1.2.2 Comparison to ARARs and TBCs Each of the alternatives evaluated, with appropriate design and planning, meet ARARs and TBCs. 2.10.2 Primary balancing criteria 2.10.2.1 Long-term effectiveness and permanence Long-term effectiveness and permanence refers to expected residual risk and the ability of a remedy to maintain reliable protection of human health and the environment over time once cleanup levels have been met. This criterion includes the consideration of residual risk that will remain on site following remediation and the adequacy and reliability of controls. Alternative 2 would result in very limited to no long-term effectiveness in reducing the exposure pathways for contaminated soil, because little or no contaminated soil will be removed or covered as part of this option. With Alternative 2, only the potential for future erosion of contaminated soil is reduced. Alternative 3 would result in the greatest long-term effectiveness by removing contaminated soils from the Joslyn Site and permanently eliminating the exposure pathways associated with the contaminated soil. Alternatives 4, 5, and 6 provide better long-term effectiveness in reducing the exposure pathways than Alternative 2, by covering the contaminated soil. Alternatives 7 and 8 provide better long-term effectiveness and permanence in reducing the exposure pathways for contaminated soil than Alternatives 4, 5, and 6 because Alternatives 7 and 8 include removing a portion of the contaminated soil from the Joslyn Site; however, this removal would not be as effective as Alternative 3. Reviews will be required at least every five years to evaluate the effectiveness and permanence of any of these alternatives because hazardous substances will remain on site in concentrations above health- based screening levels. 2.10.2.2 Reduction of toxicity, mobility, and volume through treatment Reduction of toxicity, mobility, or volume through treatment refers to the anticipated performance of the treatment technologies that may be included as part of a remedy. Alternatives 2, 4, 5, and 6 do not include treatment as a component of the remedy. Therefore, these alternatives would not significantly alter the toxicity or volume of contamination at the Site. Alternative 2 would not reduce mobility. Alternatives 4, 5, 6, 7, and 8 would reduce mobility by capping contaminated soils. Alternatives 7 and 8 remove a portion of the contaminated soil from the Joslyn Site and would therefore lessen the toxicity and volume of contamination at the Site. Alternative 3 reduces toxicity and volume through treatment. 2.10.2.3 Short-term effectiveness Short-term effectiveness addresses the period of time needed to implement the remedy and any adverse impacts that may be posed to workers, the community, and the environment during construction and operation of the remedy until cleanup levels are achieved. Significant stormwater events during periods of contaminated soil excavation could result in erosion and/or potential releases of contaminated soil or runoff to Middle Twin Lake. Under Alternatives 2, 3, 4, Record of Decision Operable Unit 5-Soils from West Area and Minnesota Pollution Control Agency Southern Lots Summary of Remedial Alternative Selection Joslyn Manufacturing & Supply Co. Site • July 2018 34 5, 6, 7, and 8, scheduling the contaminated soil excavation for a late fall or winter period would reduce the potential for significant stormwater events that could affect remedial operations. Alternatives 3, 6, and 7 involve excavating soils with the highest levels of contamination and staging them. Under Alternative 3, the excavated soils would be staged for loading for off-site transportation; under Alternatives 6 and 7, the excavated soils would be staged for consolidation at the Joslyn Site. Staging the excavated contaminated soils could result in longer potential exposure to higher concentrations of COCs for workers, residents of the local neighborhoods, and to surface water, as compared to Alternatives 2, 4, 5, or 8. 2.10.2.4 Implementability Implementability addresses the technical and administrative feasibility of a remedy from design through construction and operation. Factors such as availability of services and materials, administrative feasibility, and coordination with other governmental entities are also considered. Each of the eight alternatives can be implemented using generally available construction methods, equipment, and materials. However, there are several implementability issues that pertain to the specific alternatives: Alternatives 2 through 8 would require work in wetlands and the associated regulatory agency coordination and permitting. The regulatory permitting potentially required to implement Alternative 3 increases the administrative and logistical complexity of this remedy and makes it less certain that it could be implemented. Alternative 5 requires significant floodplain mitigation. Floodplain mitigation requires additional coordination and permitting with state and federal agencies, which increases the technical and administrative complexity of the remedy. Alternatives 7 and 8 also require floodplain mitigation, but less than required by Alternative 5. Alternative 8A requires coordination with offsite property owner(s) to obtain necessary floodplain mitigation. Alternative 8B creates a floodplain within OU5 of the Joslyn Site. Alternatives 6 and 7 would require coordination with the lessee of the developed portion of the Joslyn Site and significant stormwater management changes due to the proposed filling of the Azelia Avenue Pond. 2.10.2.5 Cost The estimated present worth cost for each alternative, including the No Action alternative, are summarized in Table 7. Detailed cost spreadsheets for each remedial alternative are included in the FFS (Barr, 2017). Capital cost estimates include the estimated construction cost; the cost of engineering, design, permitting, and construction observation; and contingencies specific to each alternative. Operation and maintenance cost estimates assume a project duration of 30 years, but do not reflect a discount rate. 2.10.3 Modifying criteria 2.10.3.1 Support agency acceptance Pursuant to the 1995 Deferral Pilot Agreement, the MPCA is the lead agency for remedy decisions and enforcement of Superfund cleanup requirements for the Joslyn Site. Although not required by the agreement, MPCA has provided the proposed remedy to EPA for review, and has received no notification that the selected remedy is inconsistent with the requirements of CERCLA or the NCP. Record of Decision Operable Unit 5-Soils from West Area and Minnesota Pollution Control Agency Southern Lots Summary of Remedial Alternative Selection Joslyn Manufacturing & Supply Co. Site • July 2018 35 2.10.3.2 Community acceptance MPCA sought community input throughout the remedy selection process, including informal neighborhood meetings, a formal public meeting, and by providing a public comment period. Several comments were received stating a preference for no additional remedial action to be completed. The stated reasons for the preference for no additional remedial action were primarily related to concerns with the loss of trees and habitat, and the resulting potential impacts to property values. A summary of the comments received and MPCA’s responses to the comments is included in Section 3.1. 2.10.4 Other considerations 2.10.4.1 Principal threat wastes The NCP establishes an expectation that EPA will use treatment to address the principal threats posed by a site whenever practicable. Alternative 3 meets this expectation by the excavation and offsite treatment/disposal of contaminated OU5 soils. Alternatives 4, 5, 6, 7, and 8 do not meet the NCP’s expectation of treating principal threat waste, but would utilize containment and would effectively eliminate the potential exposure pathway for human and ecological receptors. The NCP also states that treatment should be used to address principal threat wastes wherever practicable. As shown in the cost estimates in Table 7, the implementation of Alternative 3 is significantly more costly than Alternatives 4, 5, 6, 7, and 8 and is not practicable. Alternatives 5, 6, 7, and 8 provide a better balance of tradeoffs with respect to the other balancing criteria evaluated. 2.10.4.2 Wetland and floodplain mitigation Alternatives 2 through 8 would require mitigation of both temporary and/or permanent wetland impacts created by the selected remedial alternative. Alternatives 4, 5, and 8 would also require significant mitigation of the floodplain impacts to Middle Twin Lake. 2.11 Selected remedy 2.11.1 Summary of the rationale for the Selected Remedy Based on CERCLA requirements, the NCP, and detailed analysis of the remedial alternatives, Alternative 8B— Limited Onsite Consolidation with Soil Cover at West Area (Onsite Floodplain Mitigation), constitutes the best overall remedial action for operable unit OU5 at the Joslyn Site. Alternative 8B provides protection of public health and the environment and is in compliance with ARARs. Alternative 8B represents the best balance of tradeoffs with respect to the five balancing criteria for the following reasons: Alternative 8b will provide long-term effectiveness and permanence in reducing the exposure pathways by removing a portion of the contaminated soil and covering the remaining contaminated soils at the site. the contaminant mobility will be reduced by capping contaminated soils, and a portion of the contaminated soil will be removed from the Site and will therefore lessen the toxicity and volume of contamination at the site. contaminated soils will be excavated and staged, potentially resulting in longer exposure to COCs for workers, residents of the local neighborhoods, and to surface water; Alternative 8b will include staging less contaminated soils compared to other alternatives. Alternative 8b will have fewer implementability constraints compared to other alternatives. Record of Decision Operable Unit 5-Soils from West Area and Minnesota Pollution Control Agency Southern Lots Summary of Remedial Alternative Selection Joslyn Manufacturing & Supply Co. Site • July 2018 36 2.11.2 Detailed description of the Selected Remedy The Selected Remedy includes removal and offsite disposal of a portion of contaminated soil and the establishment of a consolidation area at the Joslyn Site featuring a multi-layer vegetated soil cover. The consolidation area will be located on the southern part of the West Area over contaminated soil (Figure 9a). The depth of excavation of contaminated soil will vary by sub-area as shown on Figure 9a. As described in Section 2.5.5.2, excavated contaminated soils that do not “contain” a listed waste and contain less than 10,000 ng/kg dioxin will be disposed offsite at a Subtitle D landfill, and those soils that “contain” a listed waste will be consolidated into the onsite consolidation area. The excavated areas will be backfilled to original grades with soil types similar to native soils for each area. Geotextile fabric will be placed in excavated areas prior to backfilling. An engineered cover consisting of a geotextile fabric layer, a 1.5-foot soil layer, and a 0.5-foot topsoil layer will be constructed over the consolidated soils (Figure 9b). Interim and permanent stormwater management modifications will also be designed to ensure that stormwater runoff will be appropriately routed and treated for existing and future needs (Figure 9c). Generalized stormwater drainage patterns at OU5 under current conditions, during remedial action construction activities, and following the implementation of Alternative 8B are shown on Figures 10a, 10b, and 10c, respectively. Wetland and floodplain mitigation will be required for implementation of this alternative and floodplain mitigation will be obtained on site within OU5. The selected remedy will be protective for use consistent with current zoning designation (industrial use for the West Area and residential use for the Southern Lots); however, the anticipated future land use for both areas is open space. Institutional controls are therefore necessary to prevent the possibility of direct exposure to COCs through unplanned development or unscheduled intrusive activities. Long-term inspection activities will be required to ensure the soil cap and stormwater features maintain their integrity. In summary, the selected remedy will include the following components: Engineering controls to control surface water runoff, groundwater, dust, and air quality and to ensure that RAOs are met during and after the remedy is in place. Clearing and shredding of trees from the work area. Consolidation of a portion of the excavated soils (approximately 10,000 cubic yards) in the southeastern portion of the West Area. Containment and isolation of contaminated soil within an onsite consolidation area using a non- woven geotextile fabric overlaid with a two-foot thick vegetative soil cover. Offsite disposal of a portion of the excavated soils (approximately 20,000 cubic yards) at a Subtitle D landfill. Site restoration of each sub-area: covering the contaminated excavated areas with a four-layer cover system including 0.5 feet of clean soil, geotextile fabric, additional clean soil, and a final top layer of surface soil. In particular. The surface soil will either be topsoil or wetland-like soil, depending on the existing designation as upland or wetland. The total depth of clean soil and surface soil placed in the excavated areas will be equivalent to the excavated depth to bring the areas back up to existing grade. Record of Decision Operable Unit 5-Soils from West Area and Minnesota Pollution Control Agency Southern Lots Summary of Remedial Alternative Selection Joslyn Manufacturing & Supply Co. Site • July 2018 37 Construction of the consolidation cover consisting of a non-woven geotextile overlaid with 1.5 feet of clean cover soil and 0.5 feet of topsoil, and permanent drainage features at the onsite consolidation area. Wetland and floodplain mitigation and restoration. Wetland restoration will include planting native shrubs trees that were chosen based on their ability to thrive, growth rate, size and shape, leaf type, and color. Preservation of existing trees in non-excavated areas, to the extent feasible and planting of new trees and shrubs to provide limited screening for residential areas and a portion of the lakeshore. Implementation of post-construction site inspections, maintenance, and contingency action plans to protect the remedy. Establishment of institutional controls (i.e., restrictive covenant) to restrict future land use and groundwater use. Five-year reviews of the remedy to ensure protectiveness is maintained. 2.11.3 Cost estimate of Selected Remedy The estimated present worth cost of the Selected Remedy is $4,780,000. A detailed cost breakdown for the Selected Remedy is presented in Appendix B. The information in this cost table is based on the best available information regarding the anticipated scope of the remedial alternative. Changes in the cost elements are likely to occur as a result of new information and data collected during the engineering design of the remedial action. Major changes may be documented in the form of a memorandum in the Administrative Record file, and by an explanation of significant differences, or a ROD amendment. This is an order-of-magnitude engineering cost estimate that is expected to be within +30% to -15% of the actual project cost. 2.11.4 Estimated outcomes of Selected Remedy The results from implementation of the Selected Remedy include the containment and isolation of contaminated soil that may pose a threat to human health and the environment. The Selected Remedy is fully compatible with and complementary to the remedies for OU1, OU2, OU3, and OU4. The land uses of the West Area and the Southern Lots will be restricted following implementation of the remedy. The West Area and Southern Lots are planned to remain undeveloped and used as open space with the use of institutional controls. Implementation of the remedy will resolve long-standing issues associated with a Superfund site located adjacent to residential properties and commercial development. The Selected Remedy includes a restoration plan designed to restore wetlands and provide habitat to native plants and animals, including pollinators. Implementation of the Selected Remedy will not impact groundwater use. The shallow groundwater aquifer below the West Area and the Southern Lots is not used for drinking water and is not anticipated to be used for drinking water in the future. The OU1, OU2, and OU3 groundwater and DNAPL pump-out systems would continue to operate until groundwater cleanup levels are met. Implementation of the Selected Remedy will have a minimal impact, if any, on surface water quality of Middle Twin Lake, and may provide a benefit by reducing suspended solid or phosphorous loading. The final cleanup goals and the basis for the cleanup goals are discussed further in Section 2.8. These cleanup goals are also protective of ecological receptors. Record of Decision Operable Unit 5-Soils from West Area and Minnesota Pollution Control Agency Southern Lots Summary of Remedial Alternative Selection Joslyn Manufacturing & Supply Co. Site • July 2018 38 2.12 Statutory determinations 2.12.1 Protection of human health and the environment The Selected Remedy for OU5 of the Joslyn Site satisfies the statutory requirement for protection of human health and the environment through containment, engineering controls, and/or institutional controls. The Selected Remedy achieves substantial risk reduction and protects human receptors because direct contact or ingestion of contaminated soil would be prevented through the isolation and containment of contaminated soil. Institutional controls would also be implemented to ensure appropriate future land use. The Selected Remedy would reduce the risks to both human and ecological receptors and is anticipated to manage short-term risks and cross-media impacts. 2.12.2 Compliance with applicable or relevant and appropriate requirements Tables 6-1 through 6-5 summarize the federal and state ARARs and TBCs compiled for this project. The Selected Remedy would comply with all ARARs and TBCs in Tables 6-1 through 6-5 as shown in the “Potential ARAR/TBC Evaluation” column. 2.12.3 Cost effectiveness The cost effectiveness of the Selected Remedy was assessed by comparing the “overall effectiveness” of the remedy (i.e., long-term effectiveness and permanence; reduction in toxicity, mobility and volume through treatment; and short-term effectiveness) to the other alternatives. The cost effectiveness of the Selected Remedy and the other alternatives are evaluated in a cost effectiveness matrix in Table 8. The Selected Remedy is determined to be cost effective because it reduces human health and ecological risks to acceptable levels, and because the overall protectiveness of the remedy is proportional to the overall cost of the remedy. 2.12.4 Permanent and alternative treatment solutions The Selected Remedy for OU5 soils represents the optimal extent to which permanent solutions and treatment technologies can be utilized in a practical and cost-effective manner. Of those alternatives that are protective of human health and the environment, and comply with ARARs, the Selected Remedy provides the best balance of tradeoffs in terms of the five balancing criteria, while also considering the statutory preference for treatment as a principal element and in consideration of community input. 2.12.5 Preference for treatment as a principal element The Selected Remedy represents a permanent solution with respect to the principal threats posed by OU5 soils. However, the principal threats are being contained without treatment. The rationale for not choosing alternative remedial actions that would completely satisfy this statutory preference is based upon technical feasibility, consideration of short-term risk to human and ecological receptors, and a high cost. 2.12.6 Five-year review requirements Since this remedy would result in hazardous substances, pollutants, or contaminants remaining on site above levels that allow for unlimited use and unrestricted exposure, a review will be conducted within Record of Decision Operable Unit 5-Soils from West Area and Minnesota Pollution Control Agency Southern Lots Summary of Remedial Alternative Selection Joslyn Manufacturing & Supply Co. Site • July 2018 39 five years after initiation of remedial action, and every five years thereafter, to ensure that the remedy is, or will be, protective of human health and the environment. 2.13 Documentation of significant changes for preferred alternative of proposed plan The MPCA issued a Proposed Plan to implement Alternative 8B in March 2017. Following publication of the Proposed Plan, MPCA administered a public comment period and held a public meeting. The Selected Remedy does not differ significantly from the Proposed Plan. However, though not necessary as part of the remedy, MPCA requested that Joslyn reconsider the post-remedy restoration plan based on comments received during the public comment period. In response, Joslyn agreed to increase the number of trees and shrubs that would be planted following remedy implementation. 2.14 References Barr Engineering Company (Barr), 1981. Hazardous Waste Investigation Disposal Site A, B, & C Brooklyn Center Facility prepared for Joslyn Manufacturing and Supply Co. December 1981. Barr, 1986. Remedial Investigation/Alternatives Report Brooklyn Center Wood Treating Site, prepared for Joslyn Corporation. January 1986. Barr, 1990. 1989 Annual Monitoring Report, Joslyn Manufacturing Co. Site, Brooklyn Center, Minnesota. March 1990. Barr, 1993. Response Action Final Report Part I (Excavation) and 1992 Annual Report Operable Unit 4 – Contaminated Soil. November 1993. Barr, 1997. Letter from Lawrence D. Dalen to Mr. David Douglas (MPCA), regarding West Area Investigation, Joslyn Manufacturing Co. Site, Brooklyn Center, Minnesota. June 2, 1997. Barr, 1998. 1997 Annual Operations and Monitoring Report for Operable Unit 4 – Joslyn Manufacturing Co. Site, Brooklyn Center, Minnesota. March, 1998. Barr, 1999a. West Area – 3 Soil Excavation – Joslyn Manufacturing Co. Site, Brooklyn Center, Minnesota. May 1999. Barr, 1999b. Western LTU Soil Excavation – Joslyn Manufacturing Co. Site, Brooklyn Center, Minnesota. June 1999. Barr, 2000. Sampling and Analysis Plan - Supplemental West Area Characterization, Joslyn Manufacturing Co. Site, Brooklyn Center, MN. July, Revised October 2000. Barr, 2001. Supplemental West Area Characterization Report, Joslyn Manufacturing Co. Site, Brooklyn Center, MN. May 2001, Revised October 2001. Barr, 2003. West Area Remedial Investigation Report, Joslyn Manufacturing Former Wood Treating Site, Brooklyn Center, Minnesota. October 2003. Barr, 2005a. Letter from Dale Finnesgaard (Barr) to David Douglas (MPCA) regarding Report of Investigation Results- Residential Lots South of the West Area, Joslyn Manufacturing Company Site; Brooklyn Center, Minnesota. May 9, 2005. Record of Decision Operable Unit 5-Soils from West Area and Minnesota Pollution Control Agency Southern Lots Summary of Remedial Alternative Selection Joslyn Manufacturing & Supply Co. Site • July 2018 40 Barr, 2005b. DRAFT Implementation Report, Middle Twin Lake, Fish Tissue Study, Brooklyn Center, Minnesota. Prepared for Joslyn Manufacturing Company. October 2005. Barr, 2006a. Review and Critique of “Middle Twin Lake Sediment Sampling and Analytical Report”. Prepared for Joslyn Manufacturing Company. January 2006. Barr, 2006b. Middle Twin Lake Fish Tissue Study Implementation Report. Brooklyn Center, Minnesota. Prepared for Joslyn Manufacturing Company. May 2006. Barr, 2007. Sediment Sampling and Analyses Report, Middle Twin Lake, Brooklyn Center, Minnesota. December 2007. Barr, 2009. Letter from Dale Finnesgaard (Barr) to Steve Schoff (MPCA) regarding Southern Lot Soil Quality – Joslyn Manufacturing Site. December 2, 2009. Barr, 2012. Wetland Delineation Report, Joslyn Manufacturing & Supply Co. Site, Brooklyn Center, Minnesota. November 1, 2012. Barr, 2014. Letter from Dale Finnesgaard (Barr) to Steve Schoff (MPCA) regarding Additional Soil Characterization, Operable Unit 5 – Joslyn Manufacturing & Supply Co. Site. May 27, 2014. Barr, 2015. Letter from Dale Finnesgaard (Barr) to Steve Schoff (MPCA) regarding Additional Soil Characterization, Operable Unit 5 – Joslyn Manufacturing & Supply Co. Site. June 12, 2015. Barr, 2017. Focused Feasibility Study – REVISION 3, Operable Unit 5 – West Area Soils, Joslyn Manufacturing & Supply Co. Site, Brooklyn Center, Minnesota. July 2013. Bay West, Inc. (Bay West), 2004. Sediment Sampling and Analytical Report, Joslyn Manufacturing Site, Brooklyn Center, Minnesota. Prepared for the Minnesota Pollution Control Agency. June 2004. Canadian Council of Ministers of the Environment (CCME), 2002. Canadian Sediment Quality Guidelines for the Protection of Aquatic Life. Summary Table. City of Brooklyn Center, 2010. Brooklyn Center Comprehensive Plan 2030. February 2010. Crane, J. L.; MacDonald, D. D.; Ingersoll, C. G.; Smorong, D. E.; Lindskoog, R. A.; Severn, C. G.; Berger, T. A.; Field, L. J. 2000. Development of a framework for evaluating numerical sediment quality targets and sediment contamination in the St. Louis River Area of Concern. U.S. Environmental Protection Agency, Great Lakes National Program Office, Chicago, IL. EPA-905-R-00-008. Earth Tech, 1999a. Release Sampling Results for Former Joslyn Manufacturing Company Site. Technical Memorandum No. 1. February 23, 1999. Earth Tech, 1999b. Transmittal letter to Mr. Gerald Stahnke (MPCA), regarding Additional Release Sampling Results for the West Area, Joslyn Manufacturing Co. Site, Brooklyn Center, Minnesota. March 9, 1999. Geomatrix Consultants, Inc. (Geomatrix), 2001. Azelia Avenue Extension Soil Correction Report, Joslyn Site. May 4, 2001. Geomatrix, 2002. Response Action Plan Implementation Report, Joslyn Site – Building II. January 17, 2002. Joslyn Manufacturing Company (Joslyn), 2004. Letter from Carl Grabinski (Joslyn) to David Douglas (MPCA) regarding Joslyn Manufacturing Company (Joslyn) Superfund Site. September 1, 2004. Record of Decision Operable Unit 5-Soils from West Area and Minnesota Pollution Control Agency Southern Lots Summary of Remedial Alternative Selection Joslyn Manufacturing & Supply Co. Site • July 2018 41 Joslyn, 2006. Letter from Carl Grabinski (Joslyn) to Michael Kanner (MPCA) regarding Joslyn Manufacturing Company (Joslyn) Site. January 3, 2006. Minnesota Department of Health (MDH), 2002. Public Health Assessment: Joslyn Manufacturing and Supply Company Site, West Area. August 29, 2002. MDH, 2006. Health Consultation, Middle Twin Lake Study Fish Tissue Study, Joslyn Manufacturing and Supply Company Site, City of Brooklyn Center, Hennepin County, Minnesota. Prepared in conjunction with the United States Department of Health and Human Services. June 23, 2006. MDH, 2009. “PFOS contamination identified in fish from more metro area lakes.” News Release, February 13, 2009. Minnesota Department of Natural Resources (MDNR), 2009. Fish Consumption Guidelines: Twin Lake. http://www.dnr.state.mn.us/lakefind/fca/report.html?downum=27004200, 2009 Minnesota Pollution Control Agency (MPCA), 1985. Response Order by Consent, Joslyn Manufacturing Co. Site, Brooklyn Center, Minnesota. May 1985. MPCA, 1989. Record of Decision (ROD) Joslyn Manufacturing Co. Site, Brooklyn Center, Minnesota. July 1989. MPCA, 1995. Five-Year Review Report for Joslyn Manufacturing and Supply Company Site, Brooklyn Center, Minnesota. Prepared by MPCA for the U.S. Environmental Protection Agency, Region V. December 28, 1995. MPCA, 1998. Letter from James Kelly (MPCA) to Paul Hyde (Real Estate Recycling) regarding Joslyn Site, MPCA Project Number 9730. November 2, 1998. MPCA, 1999a. Five-Year Review Report for Joslyn Manufacturing and Supply Company Site, Brooklyn Center, Minnesota. Prepared by MPCA for the U.S. Environmental Protection Agency, Region V. July 22, 1999. MPCA, 1999b. Risk-based Guidance for the Soil-Human Health Pathway, Volume 2, Technical Support Document. January, 1999. MPCA, 2000. Office Memorandum from Karen A. Studders (MPCA) to Timothy K. Scherkenbach (MPCA) regarding Approval of a Partial Deletion of the Joslyn Manufacturing and Supply Company Site from the Minnesota Environmental Response and Liability Act Permanent List of Priorities. June 1, 2000. MPCA, 2004a. Five-Year Review Report for Joslyn Manufacturing and Supply Company Site, Brooklyn Center, Minnesota. June 30, 2004. MPCA, 2004b. Letter from David Douglas (MPCA) to Ron Warren (City of Brooklyn Center) regarding Joslyn Manufacturing and Supply Company Superfund Site. August 16, 2004. MPCA, 2005a. Memorandum from David Douglas and John Betcher (MPCA) to file regarding Preliminary Remediation Goals for the West Area of the Joslyn Manufacturing and Supply Company Superfund Site. June 1, 2005. MPCA, 2005b. Letter from David Douglas (MPCA) to Carl Grabinski (Joslyn) regarding the Joslyn Manufacturing and Supply Company Superfund Site. July 12, 2005. MPCA, 2006a. Sediment Screening Values for Middle Twin Lake Sediment Human Health Evaluation. Office Memorandum from Jim Kelly of the MDH to Steve Schoff of MPCA. June 29, 2006. Record of Decision Operable Unit 5-Soils from West Area and Minnesota Pollution Control Agency Southern Lots Summary of Remedial Alternative Selection Joslyn Manufacturing & Supply Co. Site • July 2018 42 MPCA, 2006b. Disposal of Dioxin Contaminated Soil in “Subtitle D” Landfills. Office Memorandum from Stephen Thompson and Elizabeth Gawrys of MPCA to the Remediation Division of MPCA. August 29, 2006 MPCA, 2006c. Revised Sediment Screening Value for Dioxins/Furans for Middle Twin Lake. Office Memorandum from Jim Kelly of the MDH to Steve Schoff of MPCA. October 18, 2006 MPCA, 2009. Five-Year Review Report for Joslyn Manufacturing and Supply Company Site, Brooklyn Center, Minnesota. June 29, 2009. United States Environmental Protection Agency (EPA), 1996. Use of the Area of Contamination (AOC) Concept during RCRA Cleanups. Office Memorandum from Michael Shapiro, Stephen D. Luftig, and Jerry Clifford of EPA to RCRA Branch Chiefs and CERCLA Regional Managers, EPA. March 13, 1996. United States Environmental Protection Agency (EPA), 2000. Guidance for Assessing Chemical Contaminant Data for Use in Fish Advisories, Volume 2: Risk Assessment and Fish Consumption Limits, Third Edition. EPA-823-B-00-008. EPA, 2002. Notice of Deletion for a portion of the Joslyn Manufacturing and Supply Superfund Site from the National Priorities List (NPL). 53506-53507 Federal Register, Vol. 67, No. 159. August 16, 2002. EPA, 2003. Exposure and Human Health Reassessment of 2,3,7,8-Tetrachlorodibenzo-p-Dioxin (TCDD) and Related Compounds, National Academy of Sciences (NAS) Review Draft Volume 2: Properties, Environmental Levels, and Background Exposures. EPA/600/P-00/001Cb. December, 2003. EPA, 2009. National Study of Chemical Residues in Lake Fish Tissue. EPA 823-R-09-006. September 2009. EPA IRIS. Integrated Risk Information System. Accessed 2010. Van den Berg M, Birnbaum LS, Denison M, De Vito M, Farland W, Feeley M, Fiedler H, Hakansson H, Hanberg A, Haws L, Rose M, Safe S, Schrenk D, Tohyama C, Tritscher A, Tuomisto J, Tysklind M, Walker N, Peterson RE. The 2005 World Health Organization Re-evaluation of Human and Mammalian Toxic Equivalency Factors for Dioxins and Dioxin-like Compounds. Toxicol Sci. 93(2):223-41, 2006. Record of Decision Operable Unit 5-Soils from West Area and Minnesota Pollution Control Agency Southern Lots Summary of Remedial Alternative Selection Joslyn Manufacturing & Supply Co. Site • July 2018 43 Part 3: Responsiveness summary 3.1 Stakeholder issues and lead agency responses The MPCA received several comments as part of the public comment period. Summaries of the main comments and MPCA’s responses are provided below. Comment – the cleanup would not result in an environmental benefit, or might make things worse. MPCA response – dioxins, which are extremely toxic, are present at elevated concentrations in the soil and present a risk of exposure. The goal of the cleanup plan is to protect human health and the environment. Comment – an environmental impact statement is needed. MPCA response – the cleanup plan does not meet any of the thresholds that would trigger an environmental impact statement. Further, the cleanup plan was developed under Superfund criteria, which follows much of the same process as would be followed during an environmental impact statement. Comment – the residential streets are not suitable for heavy construction traffic. MPCA response – the MPCA agrees that construction vehicles should not use the residential streets and instead should access the site from the adjacent commercial development and associated streets. Comment – Middle Twin Lake could become impacted during cleanup activities. The wetlands need to be properly protected and restored. MPCA response – the MPCA, like the surrounding community, is concerned about protecting Middle Twin Lake and the site wetlands. The majority of the excavation will occur at a distance from the shoreline and protective measures will be in place to control sediment. Wetland restoration, both through onsite restoration and through offsite mitigation credit purchase, is a key component of the cleanup plan. Comment – more trees should be planted for screening and wildlife. MPCA response – trees play a significant role at the site. The restoration plan includes planting native seed mixes and a variety of trees and shrubs. The species planned are varied and have been selected based on their ability to thrive and their variety in appearance, size and shape, leaf type, and color. 3.2 Technical and legal issues Since the publication of the Proposed Plan, Joslyn has submitted a Joint Permit Application for Stormwater, Floodplain, and Wetland Alteration. The permit application was submitted to the Minnesota Department of Natural Resources (DNR), the U.S. Army Corps of Engineers (USACE), and the Shingle Creek Watershed Management Commission (SCWMC). The DNR issued an approval for work in public waters, the USACE confirmed that a permit was not required, and the SCWMC issued an approval for watershed commission requirements. The SCWMC also issued a Notice of Decision pursuant to the Minnesota Wetland Conservation Act approving the wetland replacement plan. Approval of these permits indicates that the Selected Remedy is administratively implementable. 456781 JOSLYN SITE WEST AREA SOUTHERN LOTS Middle Twin Lake Lower Twin Lake Upper Twin Lake Ryan Lake Brooklyn B lvd 49th AveFrance AveL a k e l a n d A v e France Ave NHowe Inc.Site 45th Ave N ""100 4567152 !;NBarr Footer: Date: 9/3/2010 12:11:25 PM File: I:\Projects\23\27\110\GIS\Maps\Record of Decision\Figure 1_Site Location Map.mxd User: ss11,000 0 1,000 2,000 Feet FIGURE 1 SITE LOCATION MAP JOSLYN MANUFACTURING & SUPPLY CO. BROOKLYN CENTER, MINNESOTA ""100Middle Twin Lake Upper Twin LakeUpper Twin Lake Middle Twin Lake ""100 !;NBarr Footer: ArcGIS 10.0, 2012-06-08 08:48 File: I:\Projects\23\27\110\GIS\Maps\Record of Decision\Figure 2_Historical Excavation Areas.mxd User: cls400 0 Feet Legend Historic Joslyn Site LTU Area Historical Excavation Areas 1988-1992 Source: Barr, 1993. Response Action Final Report Part I (Excavation) and1992 Annual Report Operable Unit 4-Contaminated Soil. November 1993. 1996 Source: Barr, 1997. 1996 Annual Operations and Monitoring ReportOperable Unit 4. August 1997. 1997 Source: Barr, 1998. 1997 Annual Operations and Monitoring ReportOperable Unit 4. March 1998. April 1999 Source: Barr, 1999a. West Area-3 Excavation. May 1999. June 1999 Source: Barr, 1999b. Western LTU Soil Excavation. June 1999. 1987 Aerial FIGURE 2 HISTORICAL EXCAVATION AREAS JOSLYN MANUFACTURING & SUPPLY CO. BROOKLYN CENTER, MINNESOTA Figure 3 Conceptual Site Model for OU5 Joslyn Manufacturing & Supply Co. Brooklyn Center, Minnesota P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\FFS\Current FFS and Related Documents\Figures\Figure 3 - Conceptual Site Model for OU5.doc Middle Twin Lake POND C !;NBarr Footer: Date: 9/3/2010 3:46:11 PM File: I:\Projects\23\27\110\GIS\Maps\Record of Decision\Figure 4_1945 Aerial Imagery.mxd User: ss1200 0 200 Feet Legend OU5 Parcels FIGURE 4 1945 AERIAL IMAGERY JOSLYN MANUFACTURING & SUPPLY CO. BROOKLYN CENTER, MINNESOTA Middle Twin Lake RAILROAD SPUR !;NBarr Footer: Date: 9/3/2010 3:49:28 PM File: I:\Projects\23\27\110\GIS\Maps\Record of Decision\Figure 4_1945 Aerial Imagery.mxd User: ss1200 0 200 Feet Legend OU5 Parcels FIGURE 5 1971 AERIAL IMAGERY JOSLYN MANUFACTURING & SUPPLY CO. BROOKLYN CENTER, MINNESOTA Page 1 of 1 10/26/2017 4:03 PM P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\Regulatory Classification of WA Soils\2012-02-16_8_Normalized chart for TCDD_PCP_BaP Equiv_10262017.xls 0.0001 0.001 0.01 0.1 1 10 100 1000 10000 G-4 2.5-4'**WA-4J-1I-2 0-0.5'G-5 2.5-4'**D-5I-3B-5A-1**J-2**WA-5A-3 1.5-2.5'H-4H-3F-1G-3 2.5-4'G-3 1.5-2.5'G-1H-1A-3 2.5-4'G-4 1.5-2.5'J-3I-2 1.5-2.5'**I-1G-2I-2 2.5-4'A-3 0.5-1.5'A-2C-2D-3 2.5-4'A-3 0-0.5'A-4**G-4 0.5-1.5'**H-2B-4F-2D-4C-4**WA-6NG-5 0-0.5'H-5B-3 2.5-4'**WA-8F-4G-5 1.5-2.5'D-3 1.5-2.5'I-2 0.5-1.5'G-4 0.5-1.5'**WA-2C-3 1.5-2.5'C-3 2.5-4'G-3 0-0.5'C-5G-5 0.5-1.5'**WA-1C-5RC-1E-2G-3 0.5-1.5'F-3D-2C-3 0.5-1.5'B-2D-3 0.5-1.5'E-1C-3 0-0.5'**WA-3D-3 0-0.5'D-1B-3 1.5-2.5'B-1B-3 0.5-1.5'**B-3 0-0.5'**E-3**WA-6S**WA-6MIDConcentration/SRV Sample Location Figure 6c West Area Risk Assessment Soil Quality Data Joslyn Manufacturing & Supply Co. Brooklyn Center, Minnesota TCDD Eq. (Method 4425/8290); ND=0.5 of detection limit PCP; ND=0.012 (0.0001*SRV) BaP Equiv; ND=0.0003 (0.0001*SRV) Soil Reference Values (SRVs) for OU5 Contaminants of Concern (COCs) based on Industrial Land Use TCDD Eq. = 35 ng/kg (ppt) PCP = 120 mg/kg (ppm) PAHs (BaP Equiv.) = 3 mg/kg (ppm) Sources: June 1, 2005 MPCA Memo - human and ecological preliminary remediation goals (PRGs) and January 1999 MPCA Risk Based Guidance for the Soil-Human Health Pathway, Non-detects (ND) on this chart are represented as 0.0001. ** Samples in which dioxin analysis shown were completed using EPA method 8290. Middle Twin Lake Upper Twin Lake WA-7 WA-1 WA-4 WA-2 WA-3 WA-5 WA-5 WA-6S WA-6N WA-5 WA-4 WA-6MID WA-8 SOUTHERN LOTS !;NBarr Footer: Date: 3/17/2011 4:04:13 PM File: I:\Projects\23\27\110\GIS\Maps\Record of Decision\Figure 7_Targeted Cleanup Area.mxd User: ss1300 0 300 Feet FIGURE 7 TARGETED CLEANUP AREA JOSLYN MANUFACTURING & SUPPLY CO. BROOKLYN CENTER, MINNESOTA Legend TCDD-Eq Concentration (ng/kg) Historic Joslyn Site OU5 Parcels <100 101 - 1000 1001 - 5000 >5000 Targeted Cleanup Area ····· Building 1 Building 2 Building 3 AzeliaAvenuePond Building1A Pond Building1B Pond Middle Twin LakeUpper Twin Lake Lake Breeze Avenue Azelia Avenue North51st Avenue North !;N Barr Footer: ArcGIS 10.0, 2012-06-12 10:11 File: I:\Projects\23\27\110\GIS\Maps\Record of Decision\Figure_10a_Existing_Flow_Patterns_Letter Size.mxd User: clsFIGURE 10a EXISTING FLOW PATTERNS JOSLYN MANUFACTURING & SUPPLY CO. BROOKLYN CENTER, MINNESOTA Legend Existing Stormwater Flow 0 300 600150 Feet Building 1 Building 2 Building 3 AzeliaAvenuePond Building1A Pond Building1B Pond Middle Twin LakeUpper Twin Lake Lake Breeze Avenue Azelia Avenue North51st Avenue North !;N Barr Footer: ArcGIS 10.0, 2012-06-12 10:15 File: I:\Projects\23\27\110\GIS\Maps\Record of Decision\Figure_10b_Temporary_Construction_Flow_Patterns_Letter Size.mxd User: clsFIGURE 10b TEMPORARY CONSTRUCTION FLOW PATTERNS JOSLYN MANUFACTURING & SUPPLY CO. BROOKLYN CENTER, MINNESOTA Legend Temporary Construction Stormwater Flow Gravity Flow Pumped Flow 0 300 600150 Feet Building 1 Building 2 Building 3 AzeliaAvenuePond Building1A Pond Building1B Pond Middle Twin LakeUpper Twin Lake Lake Breeze Avenue Azelia Avenue North51st Avenue North !;N Barr Footer: ArcGIS 10.4.1, 2017-09-25 08:18 File: I:\Projects\23\27\110\GIS\Maps\Record of Decision\Figure_10c_Alternative_8_Flow_Patterns _Letter Size.mxd User: rcs2FIGURE 10c ALTERNATIVE 8b FLOW PATTERNS JOSLYN MANUFACTURING & SUPPLY CO. BROOKLYN CENTER, MINNESOTA Legend Alternative 8b Stormwater Flow 0 300 600150 Feet X:\Agency_Files\MAR-Superfund Section\SuperfundRCRA\Superfund Unit 1\SR352 Joslyn OU5\ROD\Draft\Table 1_rev.doc Table 1 Contaminants of Concern and Sources Joslyn Manufacturing & Supply Co. Site Brooklyn Center, Minnesota Site Sub- Areas COCs Media Units Maximum Site Concentration Screening Level Source of Screening Level WA-1 to WA-3, WA-6 to WA-8 Dioxins Soil ng TCDD- TEQ/kg (ppt) 176,621 3.5 Industrial SRV (MPCA, 1999b) cPAHs Soil mg B[a]P- equivalents/kg (ppm) 350 0.3 Industrial SRV (MPCA, 1999b) PCP Soil mg/kg (ppm) 450 12 Industrial SRV (MPCA, 1999b) WA-4 and WA- 5 Dioxins Soil ng TCDD- TEQ/kg (ppt) 42 3.5 Industrial SRV (MPCA, 1999b) Southern Lots Dioxins Surficial Soil (<0.5 ft bgs) ng TCDD- TEQ/kg (ppt) 7.61 2 Residential SRV (MPCA, 1999b) Underlying Soil (>0.5 ft bgs) ng TCDD- TEQ/kg (ppt) 772 2 Residential SRV (MPCA, 1999b) Middle Twin Lake Dioxins Fish tissue ng TCDD- TEQ/kg (ppt) 0.242 0.015 U.S. EPA, 2009 Sediment (WA-5) ng TCDD- TEQ/kg (ppt) 6.0 5 Site-specific SSV (MPCA, 2006c) *Screening level was set at 0.1 x industrial SRV/SSV/fish tissue guideline concentration; given reasonable maximum exposure assumptions, this corresponds to 1 x 10-6 excess lifetime cancer risk. TCDD-TEQ = tetrachlorodibenzo-p-dioxin [TCDD] Toxicity Equivalency Quotient [TEQ], or TCDD-TEQ SRV = Soil Reference Value SSV = Sediment Screening Value B[a]P = Benzo(a)pyrene ppt = parts per trillion ppm = parts per million P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2013\Tables\Table 2.doc Table 2 Potential Exposure Pathways Joslyn Manufacturing & Supply Co. Site Brooklyn Center, Minnesota Site Sub-Areas Media Source Receptor Potential Exposure Route Included/ Excluded WA-1 to WA-3, WA-6 to WA-8 Soil Industrial worker Incidental ingestion, dermal absorption, inhalation of vapor Included WA-4 and WA-5 Soil Industrial worker Incidental ingestion, dermal absorption, inhalation of vapor Included Southern Lots Soil Resident Incidental ingestion, dermal absorption, inhalation of vapor Included Middle Twin Lake Fish tissue Fisher, recreational user Ingestion of predator fish, incidental ingestion of surface water, dermal absorption from surface water Included Sediment Recreational user Incidental ingestion, dermal absorption from sediment, inhalation of vapor, surface water ingestion Included Entire West Area Groundwater Resident Ingestion of tap water, dermal absorption from tap water, inhalation of vapor from tap water Excluded Soil Trespasser Incidental ingestion, dermal absorption, inhalation of vapor Excluded P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2013\Tables\Table 3.doc Table 3 Toxicity Characterization Joslyn Manufacturing & Supply Co. Site Brooklyn Center, Minnesota COC Toxicological endpoint driving PRG Weight of evidence for carcinogenicity Source Dioxins/furans Cancer (cellular growth and differentiation; induction) Likely human carcinogen U.S. EPA, 2003 cPAHs Cancer (nonspecific tumor increases at site of exposure) B2, probable human carcinogen U.S. EPA IRIS, 1994 PCP Cancer (liver, adrenal gland, connective tissue) B2, probable human carcinogen U.S. EPA IRIS, 1993 P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2017\Tables\Table Revisions\Table 4.doc Table 4 Screening-Level Risk Assessment for Current and Potential Future Land Use Joslyn Manufacturing & Supply Co. Site Brooklyn Center, Minnesota Site Sub- Areas Media Receptor COC Risk Guideline Units Guideline Value Concentration Range N of site samples > Guideline/Total WA-1 to WA-3, WA-6 to WA-8 Soil Industrial worker Dioxins MPCA SRV ng TCDD- TEQ/kg (ppt) 35 ND - 176,621 90/99 cPAHs MPCA SRV mg B[a]P- equivalents/kg (ppm) 3 ND - 350 10/76 PCP MPCA SRV mg/kg (ppm) 120 ND - 450 2/79 WA-4 and W A-5 Soil Industrial worker Dioxins MPCA SRV ng TCDD- TEQ/kg (ppt) 35 4.5 - 42 1/13 Southern Lots Soil Resident Dioxins MPCA SRV ng TCDD- TEQ/kg (ppt) 20 0.5 - 772 7/11 Middle Twin Lake Predator fish tissue Fisher Dioxins U.S. EPA Fish Tissue Guideline ng TCDD- TEQ/kg (ppt) 0.15 0.005 - 0.2421,2 1/10 Sediment Recreational user Dioxins MPCA SSV ng TCDD- TEQ/kg (ppt) 50 0.02 - 6.0 0/4 Gray rows indicate where concentrations have exceeded guideline values. 1 One fish sample showed a TCDD-TEQ value of 0.242 ppt when values below the detection limit (DL) were set to ½ DL; however, when values below the DL were set to 0, the value was 0.034 ppt, well below the guideline fish tissue value. In this assessment it is assumed that this concentration is not of human health concern. 2 Dioxin concentrations in fish tissue from reference lakes in the Twin Cities were lower than those seen in Middle Twin Lake; however, fish tissue data from other urban Midwest lakes sampled in the National Study of Chemical Residues in Lake Fish Tissue show similar dioxin concentrations (Barr, 2006b ). X:\Agency_Files\MAR-Superfund Section\SuperfundRCRA\Superfund Unit 1\SR352 Joslyn OU5\ROD\Draft\Table 5_PRGS_RGs.docx Table 5 Preliminary Remediation Goals (PRGs) / Remediation Goals (RGs) Joslyn Manufacturing & Supply Co. Brooklyn Center, Minnesota PRG / RG Classification Applicable site sub- areas Media COCs Units Value Sources Industrial worker receptor SRV West Area Soil Dioxins ng TCDD- TEQ/kg (ppt) 35 MPCA, 1999b; MPCA, 2005a cPAHs mg B[a]P- equivalents/kg (ppm) 3 MPCA, 1999b; MPCA, 2005a PCP mg/kg (ppm) 120 MPCA, 1999b; MPCA, 2005a Resident receptor SRV Southern Lots Soil Dioxins ng TCDD- TEQ/kg (ppt) 20 MPCA, 1999b Recreational use receptor SSV Middle Twin Lake Sediment Dioxins ng TCDD- TEQ/kg (ppt) 50 MPCA, 2006b Aquatic and terrestrial ecological receptor* OU5, Middle Twin Lake Soil, sediment Dioxins ng TCDD- TEQ/kg (ppt) 11.2 CCME, 2002; MPCA, 2005a cPAHs mg B[a]P- equivalents/kg (ppm) 12.2 Crane et al., 2000; MPCA, 2005a PCP mg/kg (ppm) 0.785 MPCA, 2005a *Aquatic sediment quality values are assumed to be applicable as terrestrial values, given the paucity of OU5 surface area above the OHWL TCDD-TEQ = tetrachlorodibenzo-p-dioxin [TCDD] Toxicity Equivalency Quotient [TEQ], or TCDD-TEQ SRV = Soil Reference Value SSV = Sediment Screening Value B[a]P = Benzo(a)pyrene ppt = parts per trillion ppm = parts per million P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2013\Tables\Table 6-1 to 6-5_2010-12-27 Joslyn ARAR Tables.docx Table 6-1 Potential Federal Action-Specific ARARs and TBCs Joslyn Manufacturing & Supply Co. Site Brooklyn Center, Minnesota Standard Requirement Prerequisite Citation Potential ARAR /TBC Evaluation Comments Federal Environmental Laws (except RCRA) CERCLA Addresses investigation and remediation of a release of a hazardous substance. Release of a hazardous substance. 42 USC 9601 et seq. Applicable NCP Provides organizational structure and procedures for preparing for and responding to discharges of oil and releases of hazardous substances, pollutants, and contaminants. Release of a hazardous substance. 40 CFR 300 Applicable Safe Drinking Water Act Protects the quality of public drinking water supplies from source to tap. 42 USC 300f et seq. Does not apply to OU being evaluated in this FS report. Clean Water Act Establishes structure for regulating discharges of pollutants and regulating surface water quality. Activities that affect or may affect surface water. 33 USC 1251 et seq. Applicable Surface water management would be required during construction activities. Clean Water Act Surface water quality requirements for discharges of pollutants to federally-regulated waters. Discharge of pollutants to federally-regulated waters. 33 USC 1342 40 CFR 129 Applicable Surface water management would be required during construction activities. Clean Air Act Regulates air emissions from stationary and mobile sources. Stationary or mobile source air emissions. 42 USC 7401 et seq. Applicable Only mobile sources will be excavation and trucking equipment. No stationary sources anticipated. Section 10 (Rivers and Harbors Act of 1899) Applies to activities that will obstruct or alter any navigable water of the United States. Construction activities that will potentially obstruct or alter navigable waters. 33 USC 403 Not an ARAR No activities are contemplated that would obstruct or alter any navigable waters of the United States. Resource Conservation and Recovery Act (RCRA) 42 USC 6901 et seq. Onsite waste generation Waste generator shall determine if the waste is hazardous waste. Generation of waste. 40 CFR 261 Subparts A through D Applicable Applicable for any operation where waste would be generated. Generators of Hazardous Waste Generation of contaminated soils that are characterized as hazardous wastes. Management of hazardous waste 40 CFR 262 Applicable to contaminated soil that is a hazardous waste. Applicable for any operation where hazardous waste would be generated. Transporters of Hazardous Waste Transportation of hazardous waste to off-site facilities. Transportation of hazardous waste to off-site facilities 40 CFR 263 Applicable to contaminated soil that is a hazardous waste. Applicable for any operation where hazardous waste would be transported off-site. Owners and Operators of Hazardous Waste Treatment, Storage Management of hazardous waste. Operations that include the management of hazardous waste. 40 CFR 264 Applicable to contaminated soil that is a hazardous Applicable for any operation where hazardous waste would be treated, stored or disposed of. Only the substantive portions would be P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2013\Tables\Table 6-1 to 6-5_2010-12-27 Joslyn ARAR Tables.docx Table 6-1 Potential Federal Action-Specific ARARs and TBCs Joslyn Manufacturing & Supply Co. Site Brooklyn Center, Minnesota Standard Requirement Prerequisite Citation Potential ARAR /TBC Evaluation Comments and Disposal Facilities waste. ARARs. Owners and Operators of Hazardous Waste Treatment, Storage and Disposal Facilities Management of hazardous waste at interim status facilities. Operations that include the management of hazardous waste at interim status facilities. 40 CFR 265 Applicable to contaminated soil that is a hazardous waste. 40 CFR 264 may supersede this regulation. Management of Specific Hazardous Waste and Specific Types of Facilities Management of specific hazardous wastes Operations involving recyclable materials, reclamation of lead-acid batteries, hazardous waste burned in boilers and industrial furnaces, munitions, or low level mixed wastes. 40 CFR 266 Does not apply to OU being evaluated in this FS report. These standards do not apply to contaminated soils at the site. Land Disposal Restrictions Restricts certain hazardous wastes from land disposal. Placement or disposal of soil that is a hazardous waste. 40 CFR 268 Applicable to contaminated soil that is a hazardous waste. Applicable to any operation where hazardous waste is land disposed. Disposal of Solid Waste that is not a Hazardous Waste Generator of RCRA Subtitle D regulated waste. Placement of RCRA Subtitle D waste in a landfill. 40 CFR 257 ARAR for landfill disposal or generated RCRA Subtitle D waste Applicable to onsite land disposal if RCRA Subtitle D waste is generated. P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2013\Tables\Table 6-1 to 6-5_2010-12-27 Joslyn ARAR Tables.docx Table 6-1 Potential Federal Action-Specific ARARs and TBCs Joslyn Manufacturing & Supply Co. Site Brooklyn Center, Minnesota Standard Requirement Prerequisite Citation Potential ARAR /TBC Evaluation Comments U.S. Department of Transportation General Information, Regulations and Definitions Requirements for packaging, labeling, marking, placarding, and motor vehicles used for transportation of hazardous materials. Offering of hazardous materials for transportation. 49 CFR 171 Applicable The contaminated soil properties will determine which regulations are applicable. Hazardous Materials Table, special provisions, communications, emergency response, training and security plans Each person who offers hazardous material for transportation or each carrier that transports it shall mark each package, container, and vehicle in the manner required. Offering of hazardous materials for transportation. 49 CFR 172 Applicable The contaminated soil properties will determine which regulations are applicable. Requirements for Shipments and Packagings Definitions of hazardous materials for transportation purposes; requirements for preparing hazardous materials for shipment Shipment of hazardous materials to off-site facilities 49 CFR 173 Applicable The contaminated soil properties will determine which regulations are applicable. Occupational Safety and Health Administration (OSHA) Work on Contaminated Sites Requirements for workers on uncontrolled hazardous waste sites such as training, personal protective equipment, recording and reporting work-related fatalities/injuries/illnesses. Work on uncontrolled hazardous waste sites, RCRA CA sites, and emergency response sites. 29 CFR 1904 - Recording and Reporting Occupational Injuries and Illnesses 29 CFR 1910 - Occupational Safety and Health 29 CFR 1926 – Safety and Health Regulations for Construction Applicable The remedial action at the Site would involve work on a CERCLA NPL site; therefore, the requirements of these OSHA standards must be met. Management Certain Toxic Substances Remediation of release of polychlorinated biphenols Requirements governing the remediation, release, and disposal of PCBs must be met. Remediation, release, and disposal of PCBs. 40 CFR 761 Does not apply to OU being evaluated in this FS report. PCBs are not potential contaminants of concern for the OU currently under evaluation. Dibenzo-para-Dioxins/Dibenzofurans Requirements governing the testing and reporting of chemical substances containing dibenzo-para-dioxins / dibenzofurans Manufacturing (and/or importing), or processing, a chemical substance identified under §766.25 40 CFR 766 Does not apply to OU being evaluated in this FS report. Remediation of contaminated soil does not involve the manufacturing or processing of the regulated chemical substances. Statutes and policies, and their citations, are provided as headings to identify general categories of potential ARARs for the convenience of the reader. Listing the statutes and policies does not indicate that the entire statutes or policies are considered as potential ARARs; only substantive requirements of the specific citations are considered potential ARARs. Specific potential ARARs are addressed in the table below each general heading. P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2013\Tables\Table 6-1 to 6-5_2010-12-27 Joslyn ARAR Tables.docx Table 6-2 Potential State and Local Action-Specific ARARs and TBCs Joslyn Manufacturing & Supply Co. Site Brooklyn Center, Minnesota Standard Requirement Prerequisite Citation Potential ARAR/TBC Evaluation Comments State Environmental Laws Water Pollution Control Act Administration and enforcement of laws relating to the pollution of any waters of the state. Release of pollutants to Minnesota waters. Minnesota Statute 115 Applicable Pollution Control Agency Provides organizational structure and procedures for responding to problems relating to water, air, and land pollution. Release of hazardous substance in Minnesota. Minnesota Statute 116 Applicable Water Law Provides regulations pertaining to any waters of the state, including surface water, wetlands and groundwater. Release of pollutants to Minnesota waters or activities that affect bed, banks or cross section of Minnesota waters. Minnesota Statute 103A, 103B, 103C, 103D, 103E; 103F, 103G, 103H Applicable Permits and Certifications Permits and certification for regulated activities General requirements for obtaining MPCA permit for regulated activities. Work involving a regulated activity. Minnesota Rules Ch. 7001.0010 through 7001.0210 Applicable to regulated activities Substantive permit requirements would need to be met for regulated activities. Hazardous waste facility permit Requirements for hazardous waste facility permit. Construction of a hazardous waste management facility in Minnesota. Minnesota Rules Ch. 7001.0500 through 7001.0730 Applicable to regulated activities Substantive permit requirements would need to be met for regulated activities. NPDES Permits Requirements for treatment and monitoring of discharges to waters of the state. Discharge of a pollutant to waters of the state. Minnesota Rules Ch. 7001.1000 through 7001.1150 Applicable to regulated activities Substantive permit requirements would need to be met for regulated activities. Surface runoff would be managed with a Storm Water Pollution Prevention Plan (SWPPP). Certifications Requirements for certification for regulated activities. Requirement to obtain certification by section 401 of the Clean Water Act. Minnesota Rules Ch. 7001.1400 through 7001.1470 Does not apply to OU being evaluated in this FS report. Solid Waste Management Facility Requirements for permitting a soil waste management facility. Construction of a solid waste management facility in Minnesota Minnesota Rules Ch. 7001.3000 through 7001.3550 Applicable to regulated activities Substantive permit requirements would need to be met for regulated activities. P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2013\Tables\Table 6-1 to 6-5_2010-12-27 Joslyn ARAR Tables.docx Table 6-2 Potential State and Local Action-Specific ARARs and TBCs Joslyn Manufacturing & Supply Co. Site Brooklyn Center, Minnesota Standard Requirement Prerequisite Citation Potential ARAR/TBC Evaluation Comments Hazardous Waste Regulations Onsite waste generation Waste generator shall determine if the waste is hazardous waste. Generation of waste. Minnesota Rules Ch. 7045.0102 through 7045.0155 Applicable Applicable for any operation where waste would be generated. Generators of Hazardous Waste Generation of contaminated soils that are characterized as hazardous wastes. Management of hazardous waste Minnesota Rules Ch. 7045.0205 through 7045.0325 Applicable to contaminated soil that is a hazardous waste. Applicable for any operation where hazardous waste would be generated. Transporters of Hazardous Waste Transportation of hazardous waste to off-site facilities. Transportation of hazardous waste to off-site facilities Minnesota Rules Ch. 7045.0450 through 7045.0397 Applicable to contaminated soil that is a hazardous waste. Applicable for any operation where hazardous waste would be transported off-site. Owners and Operators of Hazardous Waste Treatment, Storage and Disposal Facilities Management of hazardous waste. Operations that include the management of hazardous waste. Minnesota Rules Ch. 7045.0450 through 7045.0551 Applicable to contaminated soil that is a hazardous waste. Applicable for any operation where hazardous waste would be treated, stored or disposed of. Only the substantive portions would be ARARs. Owners and Operators of Interim Status Hazardous Waste Treatment, Storage and Disposal Facilities Management of hazardous waste at interim status facilities. Operations that include the management of hazardous waste at interim status facilities. Minnesota Rules Ch. 7045.0552 through 7045.0686 Applicable to contaminated soil that is a hazardous waste. Minnesota Rules 7045.0450 through 7045.0551 may supersede this regulation. Management of Specific Hazardous Waste and Specific Types of Facilities Management of specific hazardous wastes Operations involving recyclable materials, reclamation of lead-acid batteries, hazardous waste burned in boilers and industrial furnaces, munitions, or spent or waste household batteries. Minnesota Rules Ch. 7045.0652 through 7045.0686 Does not apply to OU being evaluated in this FS report. These regulations do not apply to contaminated soils at the site. P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2013\Tables\Table 6-1 to 6-5_2010-12-27 Joslyn ARAR Tables.docx Table 6-2 Potential State and Local Action-Specific ARARs and TBCs Joslyn Manufacturing & Supply Co. Site Brooklyn Center, Minnesota Standard Requirement Prerequisite Citation Potential ARAR/TBC Evaluation Comments Management of Used Oil Management of used oil Operations involving management of used oil. Minnesota Rules Ch. 7045.0692 through 7045.0990 Does not apply to OU being evaluated in this FS report. These regulations do not apply to contaminated soils at the site. County Regulation of Hazardous Waste Management Procedures for the MPCA’s overview of county hazardous waste programs MPCA approved county ordinance describing their Hazardous Waste Programs Minnesota Rules Ch. 7045.1000 through 7045.1030 Applicable to regulated activities. Hennepin County has an MPCA approved county ordinance detailing their hazardous waste programs. Land Disposal Restrictions Restricts certain hazardous wastes from land disposal. Placement or disposal of soil that is a hazardous waste. Minnesota Rules Ch. 7045.1390 through 7045.1400 Applicable to contaminated soil that is a hazardous waste. Applicable to any operation where hazardous waste is land disposed. Solid Waste General requirements for management of solid waste. Requirements and standards for solid waste Generation of a solid waste Minnesota Rules Ch. 7035.0300 through 7035.0605 Applicable to regulated activities Solid waste requirements would be applicable for storage, transport and disposal of contaminated soils generated during remedial activities. Individual Properties Responsibility for management of solid waste Generation of solid waste Minnesota Rules Ch. 7035.0700 through 7035.0805 Applicable to regulated activities Solid waste requirements would be applicable for storage, transport and disposal of contaminated soils generated during remedial activities. Industrial Solid Waste Land Disposal Facilities Requirements for industrial solid waste land disposal facilities Generation and management of an industrial solid waste Minnesota Rules Ch. 7035.1590 through 7035.2500 Applicable to regulated activities Solid waste requirements would be applicable for storage, transport and disposal of contaminated soils generated during remedial activities. Solid Waste Management Facilities Financial Requirements Requirements for cost estimates and financial assurances documentation Construction of a industrial solid waste land disposal facility Minnesota Rules Ch. 7035.2665 through 7035.2805 Applicable to regulated activities Solid waste requirements would be applicable for storage, transport and disposal of contaminated soils generated during remedial activities. P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2013\Tables\Table 6-1 to 6-5_2010-12-27 Joslyn ARAR Tables.docx Table 6-2 Potential State and Local Action-Specific ARARs and TBCs Joslyn Manufacturing & Supply Co. Site Brooklyn Center, Minnesota Standard Requirement Prerequisite Citation Potential ARAR/TBC Evaluation Comments Solid Waste Management Facility Specific Technical Requirements Requirements for facilities that dispose of mixed municipal solid waste in or on the land. Management of a mixed municipal waste landfill Minnesota Rules Ch. 7035.2815 through 7035.2915 Does not apply to OU being evaluated in this FS report. Soil remediation would not involve management of mixed municipal waste. Abandonment of motor vehicles and scrap metal Requirement for disposal and reuse of abandoned motor vehicles and other scrap metal Disposal and reuse of abandoned motor vehicles and other scrap metal Minnesota Rules Ch. 7035.3000 through 7035.3600 Does not apply to OU being evaluated in this FS report. Soil remediation would not involve disposal or reuse of abandoned motor vehicles or scrap metal. Solid Waste Programs and Projects Requirements for application procedure for grants-in-aid, state requirements, approval of applications, and payments for programs or projects which will encourage both the reduction of the amount of material entering the solid waste stream and the reuse and recycling of solid waste. Plan for facility meeting requirements Minnesota Rules Ch. 7035.4000 through 7035.6000 Does not apply to OU being evaluated in this FS report. Soil remediation project would likely meet requirements. Infectious Waste Requirements for owners and operators of facilities, commercial transporters and all infectious waste. Generation and management of infectious waste Minnesota Rules Ch. 7035.9100 through 7035.9150 Does not apply to OU being evaluated in this FS report. Soil remediation would not involve infectious waste. Disposal of Dioxin Contaminated Soil in Subtitle D Landfills Provides conditions for disposal of dioxin contaminated soil in a Minnesota Subtitle D landfill. Dioxin-contaminated soil may be placed in a Minnesota “Subtitle D” facility if TEQDF ≤ 10 µg/kg. Disposal of dioxin-contaminated soil in a MPCA-permitted Subtitle D landfill. MPCA Office Memorandum to Remediation Division from Stephen Thompson and Elizabeth Gawrys. August 29, 2006 TBC MPCA policy statement. Some of the soils considered in the FS exceed the 10 µg/kg TEQDF requirement. In addition, the MPCA concluded that: “If soils are not allowed to be disposed of in a Subtitle D Landfill, the only other viable option is to leave the contamination in place, which makes for more potential future human health exposure as compared to managing the soil in a landfill.” P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2013\Tables\Table 6-1 to 6-5_2010-12-27 Joslyn ARAR Tables.docx Table 6-2 Potential State and Local Action-Specific ARARs and TBCs Joslyn Manufacturing & Supply Co. Site Brooklyn Center, Minnesota Standard Requirement Prerequisite Citation Potential ARAR/TBC Evaluation Comments Remediation of Residential and Commercial/Industrial Property under MPCA VIC Program MPCA VIC guidance Contaminated site – enrollment in MPCA VIC program http://www.pca.state.mn.us/cleanup/vic-guidedoc.htm. TBC Applicable to remediation of brownfield sites under MPCA VIC program. Water Supply Regulations Connection to public sewer State Plumbing Code (MDH) Use of public sewer and water systems and plumbing materials and methods Minnesota Rules Ch. 4715 Does not apply to OU being evaluated in this FS report. A plumbing connection would not be expected for the remedial activities. Public Water Resource Water appropriation permitting, standards and criteria for alterations to structure of public water (DNR). Plans to appropriate water or alter structure of public water Minnesota Rules Ch. 6115 Does not apply to OU being evaluated in this FS report. No plans to appropriate water. New well construction in contaminated area Allows for designation of special Well Construction Area (MDH) Conditions requiring Special Well Construction Area designation Minnesota Rules Ch. 4725.3659 Does not apply to OU being evaluated in this FS report. A special Well Construction Area will not be designated as part of a remedial action. Monitoring well installation or abandonment Well and boring construction, use, maintenance, and sealing information (MDH) Water Well Code Minnesota Rules Ch. 4725 Applicable Wells may be installed or abandoned as part of remedial activities. Certification of Environmental Laboratories Laboratory accreditation requirements for the State of Minnesota (MDH). Requirement that analyses be conducted by a certified lab. Minnesota Statute 144.97 through 144.98 Minnesota Rules Ch. 4740 Minnesota Rules Ch. 4740.2010 through 4740.2040 Applicable Laboratories that provide services for this project would be accredited for the appropriate testing methods. Surface Water Quality Water Pollution Control Act Regulates point source discharges to waters of the state. Point source discharges to waters of the state Minnesota Statute 115 Applicable P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2013\Tables\Table 6-1 to 6-5_2010-12-27 Joslyn ARAR Tables.docx Table 6-2 Potential State and Local Action-Specific ARARs and TBCs Joslyn Manufacturing & Supply Co. Site Brooklyn Center, Minnesota Standard Requirement Prerequisite Citation Potential ARAR/TBC Evaluation Comments Water of the State Classifies waters of the state and establishes standards Standards for Surface Waters Minnesota Rules Ch. 7050 Applicable Groundwater Quality Discharge to groundwater Nondegradation goal, prohibition of discharge to saturated zone, limitation on discharge to unsaturated zone, remediation requirements. Discharges to underground waters Minnesota Rules Ch. 7060 Applicable Best management practices would be applicable during remediation to prevent degradation of groundwater quality. Groundwater use or contact Establishes human health based groundwater standards (MDH) Release of hazardous substances to drinking water aquifer Minnesota Rules Ch. 4717.7500 and 4717.7801 to 4717.7900 Not an ARAR for pathways of concern Air Quality Air emissions Duty to notify and abate excessive or abnormal unpermitted air emissions Abnormal unpermitted air emissions Minnesota Statute 116.061 Applicable These regulations would be applicable in connection with activities that disturb soil and result in emissions during remedial activities. Air emissions Air quality rules Air emissions Minnesota Rules Chs. 7005, 7007, 7017 Applicable These regulations would be applicable in connection with activities that disturb soil and result in emissions during remedial activities. Air emissions Standards of performance and emissions inventory Stationary emission source Minnesota Rules Chs. 7019 Does not apply to OU being evaluated in this FS report. These regulations would be applicable to emissions from stationary sources and no stationary source is anticipated with remediation. Air emissions Air emissions and waste management permits Requires permits for air emission sources Minnesota Statute 116.081 Does not apply to OU being evaluated in this FS report. The remedial actions would not involve the construction or modification of air or waste treatment facilities. P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2013\Tables\Table 6-1 to 6-5_2010-12-27 Joslyn ARAR Tables.docx Table 6-2 Potential State and Local Action-Specific ARARs and TBCs Joslyn Manufacturing & Supply Co. Site Brooklyn Center, Minnesota Standard Requirement Prerequisite Citation Potential ARAR/TBC Evaluation Comments Noise Pollution Control Sound generation Standards for noise generated during operations. Generation of noise during site activities Minnesota Rules Ch. 7030 Applicable May need a waiver of this requirement if operation of construction equipment exceeds noise standards. Health and Safety Worker protection Standards for worker health, safety and training Health and Safety Minnesota Rules Ch. 5205 Applicable Requirements would be met for health and safety of workers. Property Use in Superfund Remedial Action Decisions Property use Incorporating property use into cleanup decisions Need for remedial action decision. Use of institutional controls as part of remedial actions. MPCA Guidance on Incorporation of Planned Property Use into Site Decisions TBC Useful in setting PRGs and in defining the appropriate use of institutional controls. Shingle Creek Watershed Management Organization Rules and Standards Stormwater Management Manage subwatershed discharge rates and flood storage volumes to be consistent with the Commission’s and local water resources management plans. Plans for land or site development adjacent to or within a lake, wetland, or natural or altered watercourse as listed in the final inventory of Protected Waters and Wetlands, as prepared by the DNR. Shingle Creek WMO, Rule D Applicable A stormwater management plan will be prepared and submitted for review and approval Erosion and Sediment Control Control runoff and erosion during land disturbing activities Plans for projects covered by Rule D. Shingle Creek WMO, Rule E Applicable An erosion and sediment control plan will be prepared and submitted for review and approval P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2013\Tables\Table 6-1 to 6-5_2010-12-27 Joslyn ARAR Tables.docx Table 6-3 Potential Federal Location-Specific ARARs and TBCs Joslyn Manufacturing & Supply Co. Site Brooklyn Center, Minnesota Standard Requirement Prerequisite Citation Potential ARAR /TBC Evaluation Comments National Archaeological and Historical Preservation Act Within area where action may cause irreparable harm, loss, significant artifacts. Construction on previously undisturbed land would require an archaeological survey to the area. Alteration of terrain that threatens significant scientific, prehistoric, historic, or archaeological data. Substantive requirements of 36 CFR 65, National Historic Landmarks Program. Not an ARAR There are no known archaeological or historical sites located within the OU boundaries. Federal National Historic Preservation Act, Section 106 Historic project owned or controlled by federal agency. Action to preserve historic properties; planning of action to minimize harm to properties listed on or eligible for listing or the National Register of Historic Places. Property included or eligible for the National Register of Historic Places. Substantive Requirements of 36 CFR 800, Protection of Historic Properties; 16 USC 470 Not an ARAR There are no known archaeological or historical sites located within the OU boundaries. Historical Sites, Buildings, and Antiquities Act Historic sites Avoid undesirable impacts on landmarks. Areas designated as historic sites. 16 USC 461-467; 40 CFR 6.3, Requirements for Environmental Information Documents and Third-Party Agreement for EPA Actions Subject to NEPA Not an ARAR There are no known archaeological or historical sites located within the OU boundaries. Endangered Species Act of 1973 Critical habitat upon which endangered species or threatened species depend. Action to conserve endangered species or threatened species, including consultation with the Department of the Interior. Reasonable mitigation and enhancement measures must be taken, including live propagation, transplantation and habitat acquisition and improvement. Determination of effect upon endangered or threatened species or its habitat by conducting biological assessments. 16 USC 460 et seq. 16 USC 1531; 16 USC 1536(a) 50 CFR 81, Conservation of Endangered and Threatened Species of Fish, Wildlife, and Plant – Cooperation with the States 50 CFR 402, Interagency Cooperation – Endangered Species Action of 1973, as amended Applicable There are no records of endangered plant or animal species located on the portions of the Site where remedial actions would be conducted. P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2013\Tables\Table 6-1 to 6-5_2010-12-27 Joslyn ARAR Tables.docx Table 6-3 Potential Federal Location-Specific ARARs and TBCs Joslyn Manufacturing & Supply Co. Site Brooklyn Center, Minnesota Standard Requirement Prerequisite Citation Potential ARAR /TBC Evaluation Comments Migratory Bird Treaty Act of 1972 Migratory bird area Protects almost all species of native birds in the U.S. from unregulated “take” which can include poisoning at contaminated sites. Presence of migratory birds. 16 USC 703 Applicable if ground nesting birds present in remediation area. Response activities would be scheduled such that it is unlikely that ground nesting birds would be affected. Survey of ground nesting birds will be completed prior to remediation. Wilderness Act Wilderness Area Area must be administered in such a manner as will leave it unimpaired as wilderness and preserve its wilderness character. Federally-owned area designated as wilderness area. 16 USC 1131 et seq.; 50 CFR 35.1 et seq. Not an ARAR Remedial actions are not planned in areas located in or adjacent to an area designated as part of the National Wildlife Refuge System. National Wildlife Refuge System Wildlife Refuge Only actions allowed under the provisions of 16 USC Section 688 dd(c) may be undertaken in areas that are part of the National Wildlife Refuge System. Areas designated as part of National Wildlife Refuge System. 16 USC 668; 50 CFR 27 Not an ARAR Remedial actions are not planned in areas located in or adjacent to an area designated as part of the National Wildlife Refuge System. Fish and Wildlife Coordination Act, Fish and Wildlife Improvement Act of 1978, Fish and Wildlife Conservation Act of 1980 Area affecting stream or other water body Provides protection for actions that would affect streams, wetlands, other water bodies or protected habitats. Any action taken should protect fish or wildlife. Diversion, channeling or other activity that modifies a stream or other water body and affects fish or wildlife. 16 USC 661; 16 USC 662 16 USC 742a; 16 USC 2901; 50 CFR 83 Applicable Measures would be taken to protect water bodies that would be potentially affected. Procedures for Implementing Requirements of the Council on Environmental Quality on the National Environmental Policy Act and Executive Order 11990, Protection of Wetlands Wetland Action to minimize the destruction, loss, or degradation of wetlands. Wetlands of primary ecological significance must not be altered so that ecological systems in the wetlands are unreasonably disturbed. Wetlands as defined by Executive Order 11990 Section 7. 40 CFR 6, Appendix A excluding Sections 6(a)(2), 6(a)(4), 6(a)(6); 40 CFR 6.302 Applicable There is wetland within OU5. P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2013\Tables\Table 6-1 to 6-5_2010-12-27 Joslyn ARAR Tables.docx Table 6-3 Potential Federal Location-Specific ARARs and TBCs Joslyn Manufacturing & Supply Co. Site Brooklyn Center, Minnesota Standard Requirement Prerequisite Citation Potential ARAR /TBC Evaluation Comments Upper Mississippi River Management To ensure the coordinated development and enhancement of the Upper Mississippi River system. Cooperative effort and mutual assistance on the comprehensive planning of the use, protection, growth, and development of the Upper Mississippi River System Actions that may affect river reaches that have commercial navigation channels on the Mississippi River. 33 USC 652 Applicable Water bodies adjacent to the Site are part of the Upper Mississippi River system. Clean Water Act, Section 404 Wetland The degradation Section requires degradation or destruction of wetlands and other aquatic sites to be avoided to the extent possible. Dredged or fill material must not be discharged to navigable waters if the activity contributes to the violation of Maryland water quality standards CWA Sec. 307; jeopardizes endangered or threatened species; or violates requirements of the Title III of the Marine Protection, Research and Sanctuaries Act of 1972. Wetland as defined by Executive Order 11990 Section 7. 40 CFR 230.10; 40 CFR 231 231.1, 231.2, 231.7, 231.8) Applicable There is wetland within OU5. Wild and Scenic Rivers Act Within area affecting national wild, scenic, or recreational rivers. Avoid taking or assisting in action that will have direct adverse effect on national, wild or scenic recreational rivers. Activities that affect or may affect any of the rivers specified in Section 1276(a). 16 USC 1271 et seq. and Section 7(a); 36 CFR 297; 40 CFR 6.302(e) Not an ARAR There are no designated wild, scenic, or recreational areas within OU5. P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2013\Tables\Table 6-1 to 6-5_2010-12-27 Joslyn ARAR Tables.docx Table 6-3 Potential Federal Location-Specific ARARs and TBCs Joslyn Manufacturing & Supply Co. Site Brooklyn Center, Minnesota Standard Requirement Prerequisite Citation Potential ARAR /TBC Evaluation Comments Coastal Zone Management Within coastal zone Regulates activities affecting the coastal zone including lands thereunder and adjacent shoreline. Must conduct activities in a manner consistent with the approved State management programs. Activities affecting the coastal zone including lands thereunder and adjacent shoreland. Section 307(c) of 16 USC 1456(c); 16 USC 1451 et. seq.; 15 CFR 930; 15 CFR 923.45 Not an ARAR The Site is not located within a designated coastal zone. Coastal Barrier Resources Act, Section 3504 Within designated coastal barrier Prohibits any new federal expenditure within the Coastal Barrier Resource System. Activity within the Coastal Barrier Resource System 16 USC 3504 Not an ARAR The Site is not located within a designated coastal zone. Navigation and Navigable Waters Navigable waters Establishes regulations pertaining to activities that affect the navigation of the waters of the United States. Activities affecting navigable waters. 33 CFR 320-329 33 USC 1341 Not an ARAR Response activities would not affect navigation of waters of the United States. Magnuson Fishery Conservation and Management Act Managed Fisheries Provides for conservation and management of specified fisheries within specified fishery conservation zones (in federal waters). Presence of managed fisheries in federal waters. 16 USC 1801, et seq. Not an ARAR Response activities would not affect fisheries. Hazardous Waste Control Act (HWCA) Within 61 meters (200 feet) of a fault displaced in Holocene time New treatment, storage or disposal of hazardous waste prohibited. Resource Conservation and Recovery Act (RCRA) hazardous waste; treatment, storage or disposal of hazardous waste 40 CFR 264.18 (a) Not an ARAR The Site is not known to be within 61 meters of a fault displaced in the Holocene time. Within 100-year floodplain Facility must be designed, constructed, operated, and maintained to avoid washout. RCRA hazardous waste; treatment, storage, or disposal of hazardous waste. 40 CFR 264.18(b) Not an ARAR Portions of the OU included in this proposed action are within a 100-year floodplain. Within salt dome formation, underground mine, or cave Placement of noncontainerized or bulk liquid hazardous waste prohibited. RCRA hazardous waste placement. 40 CFR 264.18(c) Not an ARAR The Site is not located within a salt dome, underground mine, or cave. Executive Order 11988, Protection of Floodplains P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2013\Tables\Table 6-1 to 6-5_2010-12-27 Joslyn ARAR Tables.docx Table 6-3 Potential Federal Location-Specific ARARs and TBCs Joslyn Manufacturing & Supply Co. Site Brooklyn Center, Minnesota Standard Requirement Prerequisite Citation Potential ARAR /TBC Evaluation Comments Within floodplain Actions taken should avoid adverse effects, minimize potential harm, restore and preserve natural and beneficial values. Action that will occur in a floodplain, i.e., lowlands, and relatively flat areas adjoining inland and coastal waters and other flood-prone areas. 40 CFR 6, Appendix A; excluding Sections 6(a)(2), 6(a)(4), 6(a)(6); 40 CFR 6.302 Not an ARAR Portions of the OU included in this proposed action are within a designated floodplain. Rivers and Harbors Act of 1972 Navigable waters Permits are required for structures or work affecting navigable waters. Activities affecting navigable waters. 33 USC 403 Not an ARAR Response activities would not affect navigable waters. P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2013\Tables\Table 6-1 to 6-5_2010-12-27 Joslyn ARAR Tables.docx Table 6-4 Potential State and Local Location-Specific ARARs and TBCs Joslyn Manufacturing & Supply Co. Site Brooklyn Center, Minnesota Standard Requirement Prerequisite Citation Potential ARAR/TBC Evaluation Comments Endangered Species Endangered Species Protection of endangered species (DNR) Endangered Species Minnesota Rules Ch. 6134, Endangered, Threatened, Special Concern Species Applicable There are no records of endangered plant or animal species located on the portions of the OU that would be remediated. Protected Waters/Water Appropriation Surface Water Classifies lakes and wetlands, appropriation permitting (DNR) Protected Waters/Water Appropriation Minnesota Rules Ch. 6115, Public Water Resources Applicable Surface water bodies would be protected during remedial action. Surface Water Shoreland alterations or structures (DNR) Shoreland Management Minnesota Rules Ch. 6120, Shoreland and Floodplain Management Applicable Surface water bodies would be protected during remedial action. Wetlands Conservation Act Wetlands Protection of wetlands Presence of wetlands Minnesota Statute 103G.221-2373 Applicable There is wetland within OU5. Wetlands conservation Protection of wetlands, wetland functions for determining public values. Minnesota Rules 8420, Wetland Conservation Applicable There is wetland within OU5. State Advisories Fish Consumption Advisories Consumption guidelines for lakes and rivers where fish have been tested for contaminants. Advisories established by Minnesota Department of Health Fish Consumption Advice (MDH Website) TBC Fish consumption advisories have been established for Middle Twin Lake but are not applicable or relevant to remedial actions. Shingle Creek Watershed Management Organization Rules and Standards Floodplain Alteration Requires compensatory storage for floodplain fill. Alteration or filling of land below the 100-year critical flood elevation of any public waters Shingle Creek WMO, Rule F Applicable Portions of OU5 are within the 100-year floodplain. Wetland Alteration Requires replacement of affected wetlands where avoidance is not feasible and prudent. Presence of wetlands Shingle Creek WMO, Rule G Applicable There is wetland within OU5. City of Brooklyn Center Ordinances Zoning Ordinance Restricts use of property that is inconsistent with the City’s designated uses. Land development in Brooklyn Center City of Brooklyn Center Code of Ordinances, Chapter 35 Applicable within City of Brooklyn Center Designates land use classifications for the City of Brooklyn Center – would apply to future use of site. P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2013\Tables\Table 6-1 to 6-5_2010-12-27 Joslyn ARAR Tables.docx Table 6-5 Potential Federal and State Chemical-Specific ARARs and TBCs Joslyn Manufacturing & Supply Co. Site Brooklyn Center, Minnesota Standard Requirement Prerequisite Citation Potential ARAR/TBC Evaluation Comments Soil Addressing dioxin in soil at CERCLA and RCRA sites. Recommend preliminary PRGs of starting points for cleanup levels at CERCLA and RCRA sites. CERCLA/RCRA site with dioxin contamination. OSWER Directive 9200.4-26, April 13, 1998 Potential ARAR/TBC Considered in development of risk-based soil PRGs. Evaluating human health risk caused by exposure to contaminated soil. Tier 1 and Tier 2 Soil Reference Values (SRVs) Incidental soil ingestion, dermal contact with soil, and inhalation of outdoor vapors and particulates from soil. Risk-Based Guidance for the Soil – Human Health Pathway, MPCA Risk-Based Site Evaluation Manual TBC Considered in development of risk-based soil PRGs. Evaluating the risk to groundwater at sites form the soil-to-groundwater pathway Tier 1 and Tier 2 Soil Leaching Values (SLVs) Contaminants leaching to groundwater and potential exposure to groundwater. Risk-Based Guidance for Evaluating the Soil Leaching Pathway, MPCA Risk-Based Site Evaluation Manual TBC Considered in development of risk-based soil PRGs. Groundwater Groundwater, public water supplies Meet National Primary Standards for maximum contaminant levels (MCLs) Drinking water source at tap Safe Drinking Water Act (SDWA); 40 CFR 141 40 CFR 142 40 CFR 143 Does not apply to OU being evaluated in this FS report. Groundwater remediation underway under existing ROD. Hazardous substances in groundwater Establishes human health based groundwater standards (MDH) known as Health Risk Limits (HRLs) Potential exposure to groundwater Minnesota Rules Ch. 4717.7500 and 4717.7801 to 4717.7900 Does not apply to OU being evaluated in this FS report. Groundwater remediation underway under existing ROD. P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2013\Tables\Table 6-1 to 6-5_2010-12-27 Joslyn ARAR Tables.docx Table 6-5 Potential Federal and State Chemical-Specific ARARs and TBCs Joslyn Manufacturing & Supply Co. Site Brooklyn Center, Minnesota Standard Requirement Prerequisite Citation Potential ARAR/TBC Evaluation Comments Hazardous substances in groundwater Framework for evaluating groundwater contamination and managing remediation decisions. Use of groundwater for domestic purposes. Groundwater Guidance Document, MPCA Risk-Based Site Evaluation Manual Drinking Water Criteria Spreadsheet (rev. 9/08) Does not apply to OU being evaluated in this FS report. Groundwater remediation underway under existing ROD. Surface Water Surface Water Ambient Water Quality Criteria established to protect aquatic life and human consumers of water or aquatic life. Activities that affect or may affect surface water. 40 CFR 131, Water Quality Standards Applicable Remedial actions need to protect surface waters. Surface Water Screening Criteria Establishes human health-based and ecological surface water criteria Activities that affect or may affect the surface water. Surface Water Pathway Evaluation User’s Guide, Tables 1 and 11, MPCA Risk-based Site Evaluation Manual TBC Considered in development of alternatives. Remedial actions need to protect surface water. Air Ambient Air Quality Standards Establishes acceptable air concentrations Activity affects air quality. Minnesota Rules Ch. 7009 Applicable Applies to site activities. Standards for Stationary Sources Compliance with applicable state air pollution control rules for new and existing emission facilities Emission from stationary sources. Minnesota Rules Ch. 7011 (except 7011.0150 and 7011.8010) Does not apply to OUs being evaluated in this FS report. No emission facilities are planned at the Site. Standards for Stationary Sources Limits on visible emissions beyond the property boundary. Activities that generate fugitive dust. Minnesota Rules Ch. 7011.0150 Applicable Implement reasonable measures as necessary to prevent particulate matter from becoming airborne. P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2013\Tables\Table 6-1 to 6-5_2010-12-27 Joslyn ARAR Tables.docx Table 6-5 Potential Federal and State Chemical-Specific ARARs and TBCs Joslyn Manufacturing & Supply Co. Site Brooklyn Center, Minnesota Standard Requirement Prerequisite Citation Potential ARAR/TBC Evaluation Comments Standards for Hazardous Air Pollutants: Site Remediation Establishes emissions limitations and work practice standards for hazardous air pollutants emitted from site remediation activities. Emission of hazardous air pollutant. Minnesota Rules Ch. 7011.8010, adopts 40 CFR 63 Subpart GGGGG, by reference Not an ARAR Site remediation in not subject to this subpart since the site remediation will be performed under the authority of CERCLA (See 40 CFR 63.7881 (b) (2)). Intrusion Screening Values (ISV) (September 24, 2008) For evaluating the potential risks to human health caused by exposure to volatile compounds in buildings Presence of volatile compounds in soil or shallow groundwater. Risk-Based Guidance for the Vapor Intrusion Pathway, MPCA Risk-Based Site Evaluation Manual Not an ARAR No volatile compounds are present in soil or shallow groundwater. All Media Carcinogenic PAHs in media Estimating health risks from carcinogenic PAHs. Potential PAH exposure to humans MDH guidance Document, July 2, 2004. TBC Considered in development of risk-based soil PRGs. Dioxin-like compounds in media Estimating health risks from dioxin- like compounds. Potential dioxin-like compound exposure to humans MDH Guidance Document October 2006. TBC Considered in development of risk-based soil PRGs. Hazardous substances in media Guidelines and criteria for screening human health and ecological risks. Potential hazardous substance exposure to humans and ecology April 26, 1996 Working Site Screening Evaluation Guidelines. MPCA Risk-Based Site Evaluation Manual TBC Considered in development of risk-based soil PRGs. P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2017\Tables\Table Revisions\Table 7_Summary of Remedial Alternative Costs.docx Table 7 Summary of Remedial Alternative Costs Joslyn Manufacturing & Supply Co. Brooklyn Center, Minnesota Alternative Capital O&M Total Cost Alternative 1 – No Action $0 $530,000 $530,000 Alternative 2 – Stormwater Management Modifications $1,700,000 $624,000 $2,320,000 Alternative 3 – Excavation for Offsite Treatment and Disposal $67,350,000 $624,000 $67,970,000 Alternative 4 – In-Place Soil Cover $14,590,000 $624,000 $15,210,000 Alternative 5 – Onsite Consolidation with Soil Cover at West Area $4,330,000 $624,000 $4,950,000 Alternative 6 – Onsite Consolidation with Soil Cover at Azelia Avenue Pond $4,740,000 $1,131,000 $5,870,000 Alternative 7 – Limited Onsite Consolidation with Soil Cover at Building 1A Pond $4,600,000 $780,000 $5,380,000 Alternative 8A – Limited Onsite Consolidation with Soil Cover at West Area (Offsite Floodplain Mitigation) $4,730,000 $624,000 $5,350,000 Alternative 8B – Limited Onsite Consolidation with Soil Cover at West Area (Onsite Floodplain Mitigation) $4,160,000 $624,000 $4,780,000 P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2017\Tables\Table Revisions\Table 8_Cost Effectiveness Matrix.docx Table 8 Cost Effectiveness Matrix Joslyn Manufacturing & Supply Co. Site Brooklyn Center, Minnesota Alternative Cost Effective? Total Cost Incremental Cost Long-Term Effectiveness and Permanence Reduction of Toxicity, Mobility, and Volume (TMV) Through Treatment Short-Term Effectiveness Alternative 1- No Action NA1 $530,000 N/A No reduction in long-term risk No reduction of TMV No short-term risk to workers, community, or environment Alternative 2- Stormwater Management Modifications NA1 $2,320,000 +$1,790,000 + Limited reduction in long-term risk = No reduction of TMV - Controllable risk to workers, community, and environment Alternative 8B - Limited Onsite Consolidation with Soil Cover at West Area (Onsite Floodplain Mitigation) Yes $4,780,000 +$2,460,000 + Reduces long-term risk to acceptable levels + Reduction of TMV through reduction in mobility through capping and off- site disposal of some soil - Controllable risk to workers, community, and environment Alternative 5 - Onsite Consolidation with Soil Cover at West Area Yes $4,950,000 +$170,000 - Reduces long-term risk to acceptable levels - Reduction of TMV through reduction in mobility through capping = Controllable risk to workers, community, and environment Alternative 8A - Limited Onsite Consolidation with Soil Cover at West Area (Offsite Floodplain Mitigation) Yes $5,350,000 +$400,000 + Reduces long-term risk to acceptable levels + Reduction of TMV through reduction in mobility through capping and off- site disposal of some soil = Controllable risk to workers, community, and environment Alternative 7 - Limited Onsite Consolidation with Soil Cover at Building 1A Pond Yes $5,380,000 +$30,000 = Reduces long-term risk to acceptable levels = Reduction of TMV through reduction in mobility through capping and off- site disposal of some soil - Controllable risk to workers, community, and environment Alternative 6 – Onsite Consolidation with Soil Cover at Azelia Avenue Pond Yes $5,870,000 +$490,000 - Reduces long-term risk to acceptable levels - Reduction of TMV through reduction in mobility through capping = Controllable risk to workers, community, and environment Alternative 4- In Place Soil Cover No $15,210,000 +$9,340,000 = Reduces long-term risk to acceptable levels = Reduction of TMV through reduction in mobility through capping + Controllable risk to workers, community, and environment Alternative 3- Excavation for Offsite Treatment and Disposal No $67,970,000 +$52,760,000 + Reduces long-term risk to acceptable levels + Reduction of TMV through treatment - Controllable risk to workers, community, and environment. Notes: 1. These alternatives are not protective of human health or the environment and are therefore not considered cost effective. Key: + More effective compared with previous alternative - Less effective compared with previous alternative = No change compared with previous alternative Relevant Considerations for Cost Effectiveness Determination: • Site is currently open space with a perimeter fence that makes it inaccessible to the public; it is directly adjacent to Middle Twin Lake. • Targeted soil contamination cleanup area is 8.3 acres for Alternatives 3, 4, 5, 6, 7, and 8. • Alternative 3 may result in longest possible exposure to COCs during construction. Table A-1 West Area Soil Quality Data Joslyn Manufacturing Supply Co. Brooklyn Center, Minnesota Page 1 of 15 10/26/2017 P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2017\Appendices\Appendix A\Table A-1 West Area_10032017.xlsx WA-1 WA-1 WA1-2014-1 WA1-2014-2 WA-2 WA-2 WA-3 WA-4 WA-5 WA-6MID (ALTA) WA-6MID (STL) WA-6MID (CAS) WA-6MID (CAS)WA-6N WA-6S (STL) WA-6S (CAS) WA-6S (CAS) WA-6S (ALTA) 12/04/1998 10/06/2000 1/16/2014 1/16/2014 12/04/1998 10/06/2000 10/06/2000 12/04/1998 12/04/1998 10/6/2000 10/6/2000 10/6/2000 10/6/2000 10/06/2000 10/6/2000 10/6/2000 10/6/2000 10/6/2000 N N N N N N N N N N N N N N N N N N N Parameter Analysis Location Units General Parameters Carbon, total organic Lab %--4.97 ------1.31 2.90 --------26 24.8 2.51 --21.7 21.4 --1.32 pH Field pH units --7.85 ------7.99 7.43 ----------6.21 7.58 ----6.01 --7.32 Solids, percent Lab %-------------------------------------- Solids, total Lab %73 --70.4 86.8 85 --87.3 89 27 ------30.9 77.0 ----33.5 --88.4 SVOCs 1,6-Dinitropyrene Lab mg/kg -------------------------------------- 1,8-Dinitropyrene Lab mg/kg -------------------------------------- 1-Nitropyrene Lab mg/kg -------------------------------------- 2-Nitrofluorene Lab mg/kg -------------------------------------- 3-Methylcholanthrene Lab mg/kg -------------------------------------- 4-Nitropyrene Lab mg/kg -------------------------------------- 5-Methylchrysene Lab mg/kg -------------------------------------- 5-Nitroacenapthene Lab mg/kg -------------------------------------- 6-Nitrochrysene Lab mg/kg -------------------------------------- 7,12-Dimethylbenz(a)anthracene Lab mg/kg -------------------------------------- 7h-Dibenzo(c,g)carbazole Lab mg/kg -------------------------------------- Benz(a)anthracene Lab mg/kg 1.8 --0.59 < 0.29 < 0.33 --0.14 < 0.33 < 0.33 ------1.4 0.22 ----0.17 --0.36 Benzo(a)pyrene Lab mg/kg 2.8 --0.65 < 0.29 0.36 --0.17 0.42 < 0.33 ------2.3 0.24 ----0.56 --0.37 Benzo(b)fluoranthene Lab mg/kg 7.2 --1.2 0.36 0.90 --0.48 0.78 < 0.33 ------6.1 0.6 ----0.94 --0.6 Benzo(k)fluoranthene Lab mg/kg 2.1 --0.40 < 0.29 0.34 --0.28 < 0.33 < 0.33 ------2.7 0.24 ----0.43 --0.41 Chrysene Lab mg/kg 2.6 --1.2 < 0.29 0.34 --0.33 0.41 < 0.33 ------2.7 0.31 ----0.48 --0.59 Dibenz(a,h)acridine Lab mg/kg -------------------------------------- Dibenz(a,h)anthracene Lab mg/kg < 0.33 --< 0.35 < 0.29 < 0.33 --0.054 < 0.33 < 0.33 ------0.77 0.094 ----0.16 --0.091 Dibenz(a,j)acridine Lab mg/kg -------------------------------------- Dibenzo(a,e)pyrene Lab mg/kg -------------------------------------- Dibenzo(a,h)pyrene Lab mg/kg -------------------------------------- Dibenzo(a,i)pyrene Lab mg/kg -------------------------------------- Dibenzo(a,l)pyrene Lab mg/kg -------------------------------------- Indeno(1,2,3-cd)pyrene Lab mg/kg 0.65 --0.52 < 0.29 < 0.33 --0.24 < 0.33 < 0.33 ------11 1.1 ----0.71 --0.57 B(a)P Equivalent, non-detects at 0, 2002 PEFs Calc mg/kg 4.0 --0.93 0.036 0.49 --0.32 0.50 ND ------4.9 0.51 ----0.88 --0.62 B(a)P Equivalent, non-detects at 1/2, 2002 PEFs Calc mg/kg 4.1 --1.0 0.31 0.61 --0.32 0.64 0.33 ------4.9 0.51 ----0.88 --0.62 B(a)P Equivalent, non-detects at 1x, 2002 PEFs Calc mg/kg ----1.1 0.58 ------------------------------ 2-Chloronaphthalene Lab mg/kg < 0.33 --< 0.35 < 0.29 < 0.33 --< 0.005 < 0.33 < 0.33 ------<0.05 < 0.005 ----<0.05 --< 0.005 2-Methylnaphthalene Lab mg/kg < 0.33 --< 0.35 < 0.29 < 0.33 --0.022 < 0.33 < 0.33 ------0.26 < 0.005 ----0.11 --0.033 Depth Location W Sample Type Date 10/06 Table A-1 West Area Soil Quality Data Joslyn Manufacturing Supply Co. Brooklyn Center, Minnesota Page 2 of 15 10/26/2017 P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2017\Appendices\Appendix A\Table A-1 West Area_10032017.xlsx WA-1 WA-1 WA1-2014-1 WA1-2014-2 WA-2 WA-2 WA-3 WA-4 WA-5 WA-6MID (ALTA) WA-6MID (STL) WA-6MID (CAS) WA-6MID (CAS)WA-6N WA-6S (STL) WA-6S (CAS) WA-6S (CAS) WA-6S (ALTA) 12/04/1998 10/06/2000 1/16/2014 1/16/2014 12/04/1998 10/06/2000 10/06/2000 12/04/1998 12/04/1998 10/6/2000 10/6/2000 10/6/2000 10/6/2000 10/06/2000 10/6/2000 10/6/2000 10/6/2000 10/6/2000 N N N N N N N N N N N N N N N N N N N Parameter Analysis Location Units Depth Location W Sample Type Date 10/06 Acenaphthene Lab mg/kg < 0.33 --< 0.35 < 0.29 < 0.33 --< 0.005 < 0.33 < 0.33 ------0.063 0.048 ----<0.05 --0.01 Acenaphthylene Lab mg/kg < 0.33 --< 0.35 < 0.29 < 0.33 --0.023 < 0.33 < 0.33 ------0.54 0.053 ----0.13 --0.032 Anthracene Lab mg/kg 0.56 --0.53 < 0.29 < 0.33 --0.11 < 0.33 < 0.33 ------3.1 0.44 ----0.38 --0.89 B(a)P Equivalent, 1999 PEFs Lab mg/kg 3.8 ------0.45 --0.31 0.50 ND ------4.9 0.53 ----0.91 --0.62 Benzo(e)pyrene Lab mg/kg -------------------------------------- Benzo(g,h,i)perylene Lab mg/kg 0.67 --0.52 < 0.29 < 0.33 --0.15 < 0.33 < 0.33 ------3.1 0.49 ----0.38 --0.32 Carbazole Lab mg/kg -------------------------------------- Fluoranthene Lab mg/kg 4.1 --1.3 < 0.29 < 0.33 --0.2 b < 0.33 < 0.33 ------3.6 0.55 ----0.29 --0.64 Fluorene Lab mg/kg < 0.33 --< 0.35 < 0.29 < 0.33 --< 0.005 < 0.33 < 0.33 ------0.065 0.055 ----<0.05 --0.068 Naphthalene Lab mg/kg < 0.33 --< 0.35 < 0.29 < 0.33 --0.012 < 0.33 < 0.33 ------0.2 < 0.005 ----0.061 --0.025 Pentachlorophenol Lab mg/kg 4.2 --< 2.2 2.2 2.3 --39 < 0.33 < 0.33 ------120 e 0.72 ----120 --0.83 Perylene Lab mg/kg -------------------------------------- Phenanthrene Lab mg/kg 1.5 --0.59 < 0.29 < 0.33 --0.066 < 0.33 < 0.33 ------0.85 0.16 ----0.14 --0.23 Pyrene Lab mg/kg 5.1 --1.2 < 0.29 0.41 --0.33 < 0.33 < 0.33 ------3.6 0.48 ----0.49 --0.62 Chlorinated Dioxins / Furans 2,3,7,8-Dioxin, tetra Lab ng/kg 7.8 --5.56 2.65 EMPC 6.5 --9.61 < 0.1 0.56 jEMPC 1100 2000 --1330 7.18 430 --466 262 1.41 1,2,3,7,8-Dioxin, penta Lab ng/kg 63.4 --52.3 24.8 51.7 --256 0.44 jEMPC 4.2 j 20000 29000 --14100 61.6 8000 e --5760 5880 15.3 1,2,3,4,7,8-Dioxin, hexa Lab ng/kg 177 --231 94.2 218 --561 1.6 j 12.1 144000 180000 --79600 233 26000 --29700 22900 381 1,2,3,6,7,8-Dioxin, hexa Lab ng/kg 1280 --867 649 1000 --10500 5.0 45.1 168000 e 210000 --105000 627 110000 --112000 95300 495 1,2,3,7,8,9-Dioxin, hexa Lab ng/kg 502 --628 247 478 --1920 3.9 j 33.3 96900 140000 --60400 328 28000 --31900 35900 81.8 1,2,3,4,6,7,8-Dioxin, hepta Lab ng/kg 32550 e --30200 28400 19920 e --251000 125 1310 6540000 e 4400000 ej --430000 16400 2300000 e --1870000 2930000 e 10100 Dioxin, octa Lab ng/kg 267630 e --301000 388000 237280 e --465000 968 11330 e 52000000 e 7000000 ej --2030000 117000 4900000 ej --1800000 23500000 e 120000 2,3,7,8-Dibenzofuran, tetra Lab ng/kg 42.5 --27.0 12.1 28.3 --8.31 0.92 j 1.7 jEMPC 1340 1300 e --1120 4.75 130 --114 124 9.91 1,2,3,7,8-Dibenzofuran, penta Lab ng/kg 164 --111 69.3 103 --59.2 0.56 j 3.8 j 8600 10000 --6600 28.8 1000 --722 893 63.2 2,3,4,7,8-Dibenzofuran, penta Lab ng/kg 183 --113 71.3 105 --145 0.70 j 5.1 16800 8600 --12500 60.8 1300 --1840 2290 123 1,2,3,4,7,8-Dibenzofuran, hexa Lab ng/kg 1170 --887 630 793 --3050 3.7 j 33.0 62500 79000 --54300 239 37000 e --30400 30900 458 1,2,3,6,7,8-Dibenzofuran, hexa Lab ng/kg 341 --202 121 214 --1770 1.3 j 10.0 17500 22000 --14200 (1)101 8900 e --12600 8490 149 2,3,4,6,7,8-Dibenzofuran, hexa Lab ng/kg 514 --344 204 307 --1440 2.0 jEMPC 16.2 34900 12000 --17700 123 5200 --13500 13900 1410 1,2,3,7,8,9-Dibenzofuran, hexa Lab ng/kg 58.9 --< 10.7 < 7.44 44.4 *--286 < 0.06 2.1 j*23600 3600 --21000 110 500 --3730 3270 302 1,2,3,4,6,7,8-Dibenzofuran, hepta Lab ng/kg 9640 e --8560 7050 8500 e --101000 40.1 357 1210000 e 1100000 ej --151000 4230 1200000 ej --958000 1240000 e 4250 1,2,3,4,7,8,9-Dibenzofuran, hepta Lab ng/kg 1110 --504 421 686 --7300 2.2 j 24.1 79700 91000 j --12700 286 88000 j --63500 65500 437 Dibenzofuran, octa Lab ng/kg 41080 BQU --29400 35900 39420 e --618000 111 961 4840000 e 3400000 ej --504000 17700 3200000 ej --920000 7900000 e 12200 TEQ DF WHO05 , non-detects at zero for the detection limit Calc ng/kg 1065.173 ------775.13 --6182.317 4.5055 42.3523 176621 157700 --61407.2 514.029 68733 --59925.06 79709.19 571.707 TEQ DF WHO05, non-detects at half of the detection limit Calc ng/kg 1065.173 ------775.13 --6182.317 4.5585 42.3523 176621 157700 --61407.2 514.029 68733 --59925.06 79709.19 571.707 Dioxin TEQ (by method 4425)Lab ng/kg -------------------------------------- TCDD Equivalent, reporting limit at 0, TEF 2005 (EMPC @ 1)Calc ng/kg ----905 733 a ------------------------------ TCDD Equivalent, reporting limit at 0, TEF 2005 (EMPC @ 1/2)Calc ng/kg ----905 731 a ------------------------------ TCDD Equivalent, reporting limit at 1, TEF 2005 (EMPC @ 1)Calc ng/kg ----907 733 a ------------------------------ TCDD Equivalent, reporting limit at 1, TEF 2005 (EMPC @ 1/2)Calc ng/kg ----907 732 a ------------------------------ TCDD Equivalent, reporting limit at 1/2, TEF 2005 (EMPC @ 1)Calc ng/kg ----906 733 a ------------------------------ TCDD Equivalent, reporting limit at 1/2, TEF 2005 (EMPC@1/2)Calc ng/kg ----906 732 a ------------------------------ Table A-1 West Area Soil Quality Data Joslyn Manufacturing Supply Co. Brooklyn Center, Minnesota Page 3 of 15 10/26/2017 P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2017\Appendices\Appendix A\Table A-1 West Area_10032017.xlsx Parameter Analysis Location Units General Parameters Carbon, total organic Lab % pH Field pH units Solids, percent Lab % Solids, total Lab % SVOCs 1,6-Dinitropyrene Lab mg/kg 1,8-Dinitropyrene Lab mg/kg 1-Nitropyrene Lab mg/kg 2-Nitrofluorene Lab mg/kg 3-Methylcholanthrene Lab mg/kg 4-Nitropyrene Lab mg/kg 5-Methylchrysene Lab mg/kg 5-Nitroacenapthene Lab mg/kg 6-Nitrochrysene Lab mg/kg 7,12-Dimethylbenz(a)anthracene Lab mg/kg 7h-Dibenzo(c,g)carbazole Lab mg/kg Benz(a)anthracene Lab mg/kg Benzo(a)pyrene Lab mg/kg Benzo(b)fluoranthene Lab mg/kg Benzo(k)fluoranthene Lab mg/kg Chrysene Lab mg/kg Dibenz(a,h)acridine Lab mg/kg Dibenz(a,h)anthracene Lab mg/kg Dibenz(a,j)acridine Lab mg/kg Dibenzo(a,e)pyrene Lab mg/kg Dibenzo(a,h)pyrene Lab mg/kg Dibenzo(a,i)pyrene Lab mg/kg Dibenzo(a,l)pyrene Lab mg/kg Indeno(1,2,3-cd)pyrene Lab mg/kg B(a)P Equivalent, non-detects at 0, 2002 PEFs Calc mg/kg B(a)P Equivalent, non-detects at 1/2, 2002 PEFs Calc mg/kg B(a)P Equivalent, non-detects at 1x, 2002 PEFs Calc mg/kg 2-Chloronaphthalene Lab mg/kg 2-Methylnaphthalene Lab mg/kg Depth Location Sample Type Date WA4-2014-1 (0-0.5) WA4-2014-2 (0-2.5) WA4-2014-3 (0-5.5) WA4-2014-3 (5.5-6) WA4-2014-4 (0-4.5) WA4-2014-4 (4.5-5) WA4-2014-5 (0-0.5) WA4-2014-5 (2- 4.5) WA4-2014-5 (4.5-5) WA4-2014-6 (2-3.5) WA4-2014-6 (3.5-4)A-1 A-2 A-3 0-0.5'A-3 0.5-1.5'A-3 2.5-4' 1/16/2014 1/16/2014 1/16/2014 1/16/2014 1/16/2014 1/16/2014 1/16/2014 1/16/2014 1/16/2014 1/16/2014 1/16/2014 2/04/2003 2/04/2003 2/04/2003 2/04/2003 2/04/2003 0 - 0.5 ft 0 - 2.5 ft 0 - 5.5 ft 5.5 - 6 ft 0 - 4.5 ft 4.5 - 5 ft 0 - 0.5 ft 2 - 4.5 ft 4.5 - 5 ft 2 - 3.5 ft 3.5 - 4 ft FD N N N N N N N N N N N N N N N N FD N 1.08 ----------------------0.44 5.08 9.63 3.36 0.51 0.61 0.65 7.28 ----------------------7.27 7.06 6.82 7.01 7.26 7.58 7.27 ------------------------92.0 69.3 45.4 71.4 84.3 86.2 85.5 90.1 85.2 94.2 94.8 91.4 94.2 97.5 80.7 93.1 91.5 95.1 76.3 -------------- -------------------------------------- -------------------------------------- -------------------------------------- -------------------------------------- -------------------------------------- -------------------------------------- -------------------------------------- -------------------------------------- -------------------------------------- -------------------------------------- -------------------------------------- 0.26 < 0.29 < 0.27 < 0.26 < 0.28 < 0.27 < 0.26 < 0.31 < 0.33 < 0.33 < 0.26 < 0.33 < 0.36 < 0.42 < 0.61 < 0.47 < 0.40 < 0.33 < 0.39 0.29 < 0.29 < 0.27 < 0.26 < 0.28 < 0.27 < 0.26 < 0.31 < 0.33 < 0.33 < 0.26 < 0.33 < 0.36 < 0.42 < 0.61 < 0.47 < 0.40 < 0.33 < 0.39 0.45 < 0.29 < 0.27 < 0.26 < 0.28 < 0.27 < 0.26 < 0.31 < 0.33 < 0.33 < 0.26 < 0.33 < 0.36 < 0.42 < 0.61 < 0.47 < 0.40 < 0.33 < 0.39 0.32 < 0.29 < 0.27 < 0.26 < 0.28 < 0.27 < 0.26 < 0.31 < 0.33 < 0.33 < 0.26 < 0.33 < 0.36 < 0.42 < 0.61 < 0.47 < 0.40 < 0.33 < 0.39 0.43 < 0.29 < 0.27 < 0.26 < 0.28 < 0.27 < 0.26 < 0.31 < 0.33 < 0.33 < 0.26 < 0.33 < 0.36 < 0.42 < 0.61 < 0.47 < 0.40 < 0.33 < 0.39 -------------------------------------- 0.068 < 0.29 < 0.27 < 0.26 < 0.28 < 0.27 < 0.26 < 0.31 < 0.33 < 0.33 < 0.26 < 0.33 < 0.36 < 0.42 < 0.61 < 0.47 < 0.40 < 0.33 < 0.39 -------------------------------------- -------------------------------------- -------------------------------------- -------------------------------------- -------------------------------------- 0.42 < 0.29 < 0.27 < 0.26 < 0.28 < 0.27 < 0.26 < 0.31 < 0.33 < 0.33 < 0.26 < 0.33 < 0.36 < 0.42 < 0.61 < 0.47 < 0.40 < 0.33 < 0.39 --ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND ND --0.29 0.27 0.26 0.28 0.27 0.26 0.31 0.33 0.33 0.26 0.33 0.35 0.41 0.60 0.46 0.39 0.33 0.38 --0.57 0.53 0.51 0.55 0.53 0.51 0.61 0.65 0.65 0.51 0.65 0.71 0.83 1.2 0.93 0.79 0.65 0.77 < 0.005 < 0.29 < 0.27 < 0.26 < 0.28 < 0.27 < 0.26 < 0.31 < 0.33 < 0.33 < 0.26 < 0.33 < 0.36 < 0.42 < 0.61 < 0.47 < 0.40 < 0.33 < 0.39 0.007 < 0.29 < 0.27 < 0.26 < 0.28 < 0.27 < 0.26 < 0.31 < 0.33 < 0.33 < 0.26 < 0.33 < 0.36 < 0.42 < 0.61 < 0.47 < 0.40 < 0.33 < 0.39 WA-8 A-3 1.5-2.5' 2/04/20036/2000 Table A-1 West Area Soil Quality Data Joslyn Manufacturing Supply Co. Brooklyn Center, Minnesota Page 4 of 15 10/26/2017 P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2017\Appendices\Appendix A\Table A-1 West Area_10032017.xlsx Parameter Analysis Location Units Depth Location Sample Type Date Acenaphthene Lab mg/kg Acenaphthylene Lab mg/kg Anthracene Lab mg/kg B(a)P Equivalent, 1999 PEFs Lab mg/kg Benzo(e)pyrene Lab mg/kg Benzo(g,h,i)perylene Lab mg/kg Carbazole Lab mg/kg Fluoranthene Lab mg/kg Fluorene Lab mg/kg Naphthalene Lab mg/kg Pentachlorophenol Lab mg/kg Perylene Lab mg/kg Phenanthrene Lab mg/kg Pyrene Lab mg/kg Chlorinated Dioxins / Furans 2,3,7,8-Dioxin, tetra Lab ng/kg 1,2,3,7,8-Dioxin, penta Lab ng/kg 1,2,3,4,7,8-Dioxin, hexa Lab ng/kg 1,2,3,6,7,8-Dioxin, hexa Lab ng/kg 1,2,3,7,8,9-Dioxin, hexa Lab ng/kg 1,2,3,4,6,7,8-Dioxin, hepta Lab ng/kg Dioxin, octa Lab ng/kg 2,3,7,8-Dibenzofuran, tetra Lab ng/kg 1,2,3,7,8-Dibenzofuran, penta Lab ng/kg 2,3,4,7,8-Dibenzofuran, penta Lab ng/kg 1,2,3,4,7,8-Dibenzofuran, hexa Lab ng/kg 1,2,3,6,7,8-Dibenzofuran, hexa Lab ng/kg 2,3,4,6,7,8-Dibenzofuran, hexa Lab ng/kg 1,2,3,7,8,9-Dibenzofuran, hexa Lab ng/kg 1,2,3,4,6,7,8-Dibenzofuran, hepta Lab ng/kg 1,2,3,4,7,8,9-Dibenzofuran, hepta Lab ng/kg Dibenzofuran, octa Lab ng/kg TEQ DF WHO05 , non-detects at zero for the detection limit Calc ng/kg TEQ DF WHO05, non-detects at half of the detection limit Calc ng/kg Dioxin TEQ (by method 4425)Lab ng/kg TCDD Equivalent, reporting limit at 0, TEF 2005 (EMPC @ 1)Calc ng/kg TCDD Equivalent, reporting limit at 0, TEF 2005 (EMPC @ 1/2)Calc ng/kg TCDD Equivalent, reporting limit at 1, TEF 2005 (EMPC @ 1)Calc ng/kg TCDD Equivalent, reporting limit at 1, TEF 2005 (EMPC @ 1/2)Calc ng/kg TCDD Equivalent, reporting limit at 1/2, TEF 2005 (EMPC @ 1)Calc ng/kg TCDD Equivalent, reporting limit at 1/2, TEF 2005 (EMPC@1/2)Calc ng/kg WA4-2014-1 (0-0.5) WA4-2014-2 (0-2.5) WA4-2014-3 (0-5.5) WA4-2014-3 (5.5-6) WA4-2014-4 (0-4.5) WA4-2014-4 (4.5-5) WA4-2014-5 (0-0.5) WA4-2014-5 (2- 4.5) WA4-2014-5 (4.5-5) WA4-2014-6 (2-3.5) WA4-2014-6 (3.5-4)A-1 A-2 A-3 0-0.5'A-3 0.5-1.5'A-3 2.5-4' 1/16/2014 1/16/2014 1/16/2014 1/16/2014 1/16/2014 1/16/2014 1/16/2014 1/16/2014 1/16/2014 1/16/2014 1/16/2014 2/04/2003 2/04/2003 2/04/2003 2/04/2003 2/04/2003 0 - 0.5 ft 0 - 2.5 ft 0 - 5.5 ft 5.5 - 6 ft 0 - 4.5 ft 4.5 - 5 ft 0 - 0.5 ft 2 - 4.5 ft 4.5 - 5 ft 2 - 3.5 ft 3.5 - 4 ft FD N N N N N N N N N N N N N N N N FD N WA-8 A-3 1.5-2.5' 2/04/20036/2000 0.007 < 0.29 < 0.27 < 0.26 < 0.28 < 0.27 < 0.26 < 0.31 < 0.33 < 0.33 < 0.26 < 0.33 < 0.36 < 0.42 < 0.61 < 0.47 < 0.40 < 0.33 < 0.39 0.021 < 0.29 < 0.27 < 0.26 < 0.28 < 0.27 < 0.26 < 0.31 < 0.33 < 0.33 < 0.26 < 0.33 < 0.36 < 0.42 < 0.61 < 0.47 < 0.40 < 0.33 < 0.39 0.11 < 0.29 < 0.27 < 0.26 < 0.28 < 0.27 < 0.26 < 0.31 < 0.33 < 0.33 < 0.26 < 0.33 < 0.36 < 0.42 < 0.61 < 0.47 < 0.40 < 0.33 < 0.39 0.47 ------------------------------------ -------------------------------------- 0.26 < 0.29 < 0.27 < 0.26 < 0.28 < 0.27 < 0.26 < 0.31 < 0.33 < 0.33 < 0.26 < 0.33 < 0.36 < 0.42 < 0.61 < 0.47 < 0.40 < 0.33 < 0.39 -------------------------------------- 0.46 < 0.29 < 0.27 < 0.26 < 0.28 < 0.27 < 0.26 < 0.31 < 0.33 < 0.33 < 0.26 < 0.33 < 0.36 < 0.42 < 0.61 < 0.47 < 0.40 < 0.33 < 0.39 0.007 < 0.29 < 0.27 < 0.26 < 0.28 < 0.27 < 0.26 < 0.31 < 0.33 < 0.33 < 0.26 < 0.33 < 0.36 < 0.42 < 0.61 < 0.47 < 0.40 < 0.33 < 0.39 0.006 < 0.29 < 0.27 < 0.26 < 0.28 < 0.27 < 0.26 < 0.31 < 0.33 < 0.33 < 0.26 < 0.33 < 0.36 < 0.42 < 0.61 < 0.47 < 0.40 < 0.33 < 0.39 0.71 < 1.8 < 1.6 < 1.6 < 1.7 < 1.6 < 1.6 < 1.9 < 2.0 < 2.0 < 1.6 < 2.0 < 2.2 < 2.6 < 3.7 < 2.8 < 2.4 < 2.0 18 -------------------------------------- 0.09 < 0.29 < 0.27 < 0.26 < 0.28 < 0.27 < 0.26 < 0.31 < 0.33 < 0.33 < 0.26 < 0.33 < 0.36 < 0.42 < 0.61 < 0.47 < 0.40 < 0.33 < 0.39 0.43 < 0.29 < 0.27 < 0.26 < 0.28 < 0.27 < 0.26 < 0.31 < 0.33 < 0.33 < 0.26 < 0.33 < 0.36 < 0.42 < 0.61 < 0.47 < 0.40 < 0.33 < 0.39 2.76 0.443 EMPC < 0.281 < 0.241 < 0.250 < 0.216 < 0.201 < 0.254 < 0.148 < 0.180 < 0.222 < 0.188 -------------- 22.1 1.64 j 0.337 j < 0.191 < 0.151 0.191 EMPC < 0.163 1.53 j < 0.140 < 0.141 < 0.134 0.205 EMPC -------------- 72.1 4.79 0.738 j < 0.198 < 0.212 0.431 EMPC < 0.156 3.39 < 0.303 < 0.198 < 0.153 0.367 j -------------- 82.5 16.7 4.06 EMPC < 0.203 < 0.208 1.69 j < 0.153 13.2 0.780 j 0.450 EMPC 0.398 EMPC 2.07 j -------------- 98.5 12.2 1.83 j < 0.201 < 0.211 1.20 j < 0.155 8.50 0.406 jb < 0.202 0.377 EMPC 1.05 jb -------------- 10400 541 124 4.15 1.87 j 50.3 0.622 j 393 16.1 8.29 5.62 74.5 -------------- 102000 5390 e 1400 40.5 19.8 498 4.50 jb 3920 154 84.0 31.4 1050 -------------- 13.3 < 0.660 < 0.155 < 0.148 < 0.154 < 0.123 < 0.107 < 0.750 < 0.0853 < 0.112 < 0.121 < 0.137 -------------- 70.5 1.17 j < 0.142 < 0.152 < 0.148 < 0.128 < 0.137 1.09 EMPC < 0.132 < 0.115 < 0.121 < 0.169 -------------- 138 1.38 j 0.178 EMPC < 0.147 < 0.144 0.274 EMPC < 0.135 1.22 EMPC < 0.141 < 0.121 < 0.121 < 0.172 -------------- 554 10.7 0.935 EMPC < 0.148 < 0.112 1.52 j < 0.144 10.5 0.673 j 0.375 j < 0.145 1.86 j -------------- 186 EMPC 3.92 EMPC < 0.587 < 0.123 < 0.0918 0.387 j < 0.121 2.42 EMPC 0.217 j < 0.145 < 0.119 0.502 EMPC -------------- 206 7.19 0.742 EMPC < 0.139 < 0.104 0.703 EMPC < 0.136 5.09 0.374 EMPC < 0.168 < 0.133 0.762 EMPC -------------- 197 < 0.811 < 0.982 < 0.209 < 0.153 < 0.368 < 0.205 < 0.991 < 0.250 < 0.252 < 0.199 < 0.370 -------------- 4740 183 79.0 1.28 j 0.759 EMPC 17.4 0.209 EMPC 141 6.74 3.29 1.40 j 28.0 -------------- 460 8.93 2.83 EMPC < 0.314 < 0.327 1.26 j < 0.211 9.23 0.753 bEMPC < 0.272 < 0.237 1.77 j -------------- 12800 749 413 5.07 j 2.31 j 61.3 0.956 j 580 17.2 8.91 3.85 j 118 -------------- -------------------------------------- -------------------------------------- ------------------------40 b 194 227 189 56 *15 b*106 --17.3 a 3.82 a 0.0680 a 0.0329 a 1.72 a 0.00860 a 13.0 a 0.484 a 0.226 a 0.158 a 2.15 a -------------- --16.8 a 3.50 a 0.068 a 0.0291 a 1.53 a 0.00755 a 12.7 a 0.465 a 0.204 a 0.120 a 1.99 a -------------- --17.4 a 4.28 a 0.689 a 0.609 a 1.99 a 0.537 a 13.4 a 0.882 a 0.697 a 0.644 a 2.45 a -------------- --17.0 a 3.95 a 0.689 a 0.606 a 1.80 a 0.536 a 13.1 a 0.864 a 0.675 a 0.605 a 2.28 a -------------- --17.3 a 4.05 a 0.378 a 0.321 a 1.86 a 0.273 a 13.2 a 0.683 a 0.462 a 0.401 a 2.30 a -------------- --16.9 a 3.72 a 0.378 a 0.317 a 1.66 a 0.272 a 12.9 a 0.665 a 0.439 a 0.362 a 2.14 a -------------- Table A-1 West Area Soil Quality Data Joslyn Manufacturing Supply Co. Brooklyn Center, Minnesota Page 5 of 15 10/26/2017 P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2017\Appendices\Appendix A\Table A-1 West Area_10032017.xlsx Parameter Analysis Location Units General Parameters Carbon, total organic Lab % pH Field pH units Solids, percent Lab % Solids, total Lab % SVOCs 1,6-Dinitropyrene Lab mg/kg 1,8-Dinitropyrene Lab mg/kg 1-Nitropyrene Lab mg/kg 2-Nitrofluorene Lab mg/kg 3-Methylcholanthrene Lab mg/kg 4-Nitropyrene Lab mg/kg 5-Methylchrysene Lab mg/kg 5-Nitroacenapthene Lab mg/kg 6-Nitrochrysene Lab mg/kg 7,12-Dimethylbenz(a)anthracene Lab mg/kg 7h-Dibenzo(c,g)carbazole Lab mg/kg Benz(a)anthracene Lab mg/kg Benzo(a)pyrene Lab mg/kg Benzo(b)fluoranthene Lab mg/kg Benzo(k)fluoranthene Lab mg/kg Chrysene Lab mg/kg Dibenz(a,h)acridine Lab mg/kg Dibenz(a,h)anthracene Lab mg/kg Dibenz(a,j)acridine Lab mg/kg Dibenzo(a,e)pyrene Lab mg/kg Dibenzo(a,h)pyrene Lab mg/kg Dibenzo(a,i)pyrene Lab mg/kg Dibenzo(a,l)pyrene Lab mg/kg Indeno(1,2,3-cd)pyrene Lab mg/kg B(a)P Equivalent, non-detects at 0, 2002 PEFs Calc mg/kg B(a)P Equivalent, non-detects at 1/2, 2002 PEFs Calc mg/kg B(a)P Equivalent, non-detects at 1x, 2002 PEFs Calc mg/kg 2-Chloronaphthalene Lab mg/kg 2-Methylnaphthalene Lab mg/kg Depth Location Sample Type Date A-4 B-1 B-1 B-1 B-1 B-2 B-3 B-3 B-3 B-3 0.5- 1.5'B-3 0-0.5'B-3 1.5-2.5'B-3 2.5-4'B-4 B-5 C-1 C-3 0-0.5' 2/04/2003 2/02/2015 2/02/2015 2/02/2015 2/02/2015 2/04/2003 2/02/2015 2/02/2015 2/02/2015 2/04/2003 2/04/2003 2/04/2003 2/04/2003 2/04/2003 2/04/2003 2/04/2003 2/04/2003 0.5 - 2 ft 2 - 3.5 ft 6.5 - 9 ft 9 - 10 ft 3.5 - 5 ft 5 - 6.5 ft 6.5 - 9 ft N N FD N N N N N N N N N N N N N N N N FD N 5.38 6.05 5.52 3.81 2.47 h 0.553 h 0.124 h 3.03 43.7 42.2 h 11.3 h 21.2 22.8 31.3 42.3 13.9 5.34 10.5 2.79 2.87 25.8 7.31 7.32 7.47 --------6.69 ------6.34 6.65 6.24 6.22 5.93 7.37 6.87 5.95 6.09 6.07 66.9 63.2 64.7 --------70.1 ------17.0 4.10 22.9 23.9 34.1 73.5 44.4 64.6 70.3 11.2 ------80.5 74.0 82.3 83.6 --22.1 19.0 27.6 -------------------- ------------------------------------------ ------------------------------------------ ------------------------------------------ ------------------------------------------ ------------------------------------------ ------------------------------------------ ------------------------------------------ ------------------------------------------ ------------------------------------------ ------------------------------------------ ------------------------------------------ < 0.48 < 0.45 < 0.45 --------< 0.46 ------< 2.0 < 8.1 < 1.4 < 1.4 < 0.73 < 0.39 < 0.70 < 0.51 < 0.36 < 3.0 < 0.48 < 2.3 < 2.3 --------< 0.46 ------< 2.0 < 8.1 < 1.4 < 1.4 < 0.73 < 0.39 < 7.0 < 0.51 < 0.36 3.3 < 0.48 < 2.3 < 2.3 --------< 0.46 ------2.6 < 8.1 < 1.4 < 1.4 < 0.73 < 0.39 < 7.0 0.65 0.58 14 < 0.48 < 2.3 < 2.3 --------< 0.46 ------< 2.0 < 8.1 < 1.4 < 1.4 < 0.73 < 0.39 < 7.0 < 0.51 < 0.36 6.5 < 0.48 < 0.45 < 0.45 --------< 0.46 ------< 2.0 < 8.1 < 1.4 < 1.4 < 0.73 < 0.39 1.0 < 0.51 < 0.36 5.6 ------------------------------------------ < 0.48 < 2.3 < 2.3 --------< 0.46 ------< 2.0 < 8.1 < 1.4 < 1.4 < 0.73 < 0.39 < 7.0 < 0.51 < 0.36 < 3.0 ------------------------------------------ ------------------------------------------ ------------------------------------------ ------------------------------------------ ------------------------------------------ < 0.48 < 2.3 < 2.3 --------< 0.46 ------2.2 < 8.1 < 1.4 < 1.4 < 0.73 < 0.39 < 7.0 < 0.51 0.39 9.2 ND ND ----------ND ------ND ND 0.48 ND ND ND 0.010 0.065 --6.3 0.47 2.2 ----------0.45 ------2.3 8.0 1.4 1.4 0.72 0.38 6.6 0.54 --7.3 0.95 ---------------------------------------- < 0.48 < 0.45 < 0.45 --------< 0.46 ------< 2.0 < 8.1 < 1.4 < 1.4 < 0.73 < 0.39 < 0.70 < 0.51 < 0.36 < 3.0 < 0.48 < 0.45 < 0.45 --------< 0.46 ------< 2.0 < 8.1 < 1.4 < 1.4 < 0.73 < 0.39 < 0.70 < 0.51 < 0.36 < 3.0 B-1 C-2 2/04/2003 2/03/2003 Table A-1 West Area Soil Quality Data Joslyn Manufacturing Supply Co. Brooklyn Center, Minnesota Page 6 of 15 10/26/2017 P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2017\Appendices\Appendix A\Table A-1 West Area_10032017.xlsx Parameter Analysis Location Units Depth Location Sample Type Date Acenaphthene Lab mg/kg Acenaphthylene Lab mg/kg Anthracene Lab mg/kg B(a)P Equivalent, 1999 PEFs Lab mg/kg Benzo(e)pyrene Lab mg/kg Benzo(g,h,i)perylene Lab mg/kg Carbazole Lab mg/kg Fluoranthene Lab mg/kg Fluorene Lab mg/kg Naphthalene Lab mg/kg Pentachlorophenol Lab mg/kg Perylene Lab mg/kg Phenanthrene Lab mg/kg Pyrene Lab mg/kg Chlorinated Dioxins / Furans 2,3,7,8-Dioxin, tetra Lab ng/kg 1,2,3,7,8-Dioxin, penta Lab ng/kg 1,2,3,4,7,8-Dioxin, hexa Lab ng/kg 1,2,3,6,7,8-Dioxin, hexa Lab ng/kg 1,2,3,7,8,9-Dioxin, hexa Lab ng/kg 1,2,3,4,6,7,8-Dioxin, hepta Lab ng/kg Dioxin, octa Lab ng/kg 2,3,7,8-Dibenzofuran, tetra Lab ng/kg 1,2,3,7,8-Dibenzofuran, penta Lab ng/kg 2,3,4,7,8-Dibenzofuran, penta Lab ng/kg 1,2,3,4,7,8-Dibenzofuran, hexa Lab ng/kg 1,2,3,6,7,8-Dibenzofuran, hexa Lab ng/kg 2,3,4,6,7,8-Dibenzofuran, hexa Lab ng/kg 1,2,3,7,8,9-Dibenzofuran, hexa Lab ng/kg 1,2,3,4,6,7,8-Dibenzofuran, hepta Lab ng/kg 1,2,3,4,7,8,9-Dibenzofuran, hepta Lab ng/kg Dibenzofuran, octa Lab ng/kg TEQ DF WHO05 , non-detects at zero for the detection limit Calc ng/kg TEQ DF WHO05, non-detects at half of the detection limit Calc ng/kg Dioxin TEQ (by method 4425)Lab ng/kg TCDD Equivalent, reporting limit at 0, TEF 2005 (EMPC @ 1)Calc ng/kg TCDD Equivalent, reporting limit at 0, TEF 2005 (EMPC @ 1/2)Calc ng/kg TCDD Equivalent, reporting limit at 1, TEF 2005 (EMPC @ 1)Calc ng/kg TCDD Equivalent, reporting limit at 1, TEF 2005 (EMPC @ 1/2)Calc ng/kg TCDD Equivalent, reporting limit at 1/2, TEF 2005 (EMPC @ 1)Calc ng/kg TCDD Equivalent, reporting limit at 1/2, TEF 2005 (EMPC@1/2)Calc ng/kg A-4 B-1 B-1 B-1 B-1 B-2 B-3 B-3 B-3 B-3 0.5- 1.5'B-3 0-0.5'B-3 1.5-2.5'B-3 2.5-4'B-4 B-5 C-1 C-3 0-0.5' 2/04/2003 2/02/2015 2/02/2015 2/02/2015 2/02/2015 2/04/2003 2/02/2015 2/02/2015 2/02/2015 2/04/2003 2/04/2003 2/04/2003 2/04/2003 2/04/2003 2/04/2003 2/04/2003 2/04/2003 0.5 - 2 ft 2 - 3.5 ft 6.5 - 9 ft 9 - 10 ft 3.5 - 5 ft 5 - 6.5 ft 6.5 - 9 ft N N FD N N N N N N N N N N N N N N N N FD N B-1 C-2 2/04/2003 2/03/2003 < 0.48 < 0.45 < 0.45 --------< 0.46 ------< 2.0 < 8.1 < 1.4 < 1.4 < 0.73 < 0.39 < 0.70 < 0.51 < 0.36 < 3.0 < 0.48 < 0.45 < 0.45 --------< 0.46 ------< 2.0 < 8.1 < 1.4 < 1.4 < 0.73 < 0.39 < 0.70 < 0.51 < 0.36 < 3.0 < 0.48 < 0.45 < 0.45 --------< 0.46 ------< 2.0 < 8.1 < 1.4 < 1.4 < 0.73 < 0.39 < 0.70 < 0.51 < 0.36 < 3.0 ------------------------------------------ ------------------------------------------ < 0.48 < 2.3 < 2.3 --------< 0.46 ------< 2.0 < 8.1 < 1.4 < 1.4 2.0 < 0.39 < 7.0 < 0.51 0.38 8.4 ------------------------------------------ 0.63 < 0.45 < 0.45 --------< 0.46 ------< 2.0 < 8.1 < 1.4 < 1.4 < 0.73 < 0.39 1.1 < 0.51 < 0.36 4.6 < 0.48 < 0.45 < 0.45 --------< 0.46 ------< 2.0 < 8.1 < 1.4 < 1.4 < 0.73 < 0.39 < 0.70 < 0.51 < 0.36 < 3.0 < 0.48 < 0.45 < 0.45 --------< 0.46 ------< 2.0 < 8.1 < 1.4 < 1.4 < 0.73 < 0.39 < 0.70 < 0.51 < 0.36 < 3.0 < 2.9 69 69 --------8.1 ------51 71 59 < 8.4 < 4.4 < 2.4 76 < 3.1 < 2.2 55 ------------------------------------------ < 0.48 < 0.45 < 0.45 --------< 0.46 ------< 2.0 < 8.1 < 1.4 < 1.4 < 0.73 < 0.39 < 0.70 < 0.51 < 0.36 < 3.0 0.57 0.54 0.56 --------< 0.46 ------< 2.0 < 8.1 < 1.4 < 1.4 < 0.73 < 0.39 1.6 < 0.51 < 0.36 5.8 ------5.88 0.575 EMPC 0.247 EMPC < 0.307 --< 0.572 4.59 < 0.592 --< 1.0 h ---------------- ------149 17.9 5.77 < 0.773 --14.5 41.4 < 0.755 --3266.494 jh ---------------- ------522 96.4 74.2 6.51 --160 194 < 0.454 --13807.604 jh ---------------- ------11900 4510 EMPC 4620 329 --3430 1530 2.37 EMPC --34183.592 h ---------------- ------1070 292 497 101 --306 336 < 0.435 --35156.664 h ---------------- ------453000 122000 *99200 *27700 *--192000 94900 *72.3 --1106991.3 h ---------------- ------15000000 e 3050000 *762000 *289000 *--3730000 1430000 *828 --5282956.4 h ---------------- ------49.8 41.3 0.529 j < 0.280 --< 0.622 < 0.910 < 1.64 --< 1.0 h ---------------- ------316 322 2.39 EMPC < 1.07 --3.22 j 6.09 EMPC < 0.379 --< 2.5 h ---------------- ------702 697 10.9 < 1.07 --2.51 j 16.4 EMPC < 0.368 --< 2.5 h ---------------- ------4820 2230 EMPC 1040 *16.8 --443 *299 *1.09 EMPC --13247.806 jh ---------------- ------724 643 96.8 < 1.31 --< 3.74 < 4.57 < 0.354 --3687.053 jh ---------------- ------1390 1210 383 9.31 --197 133 < 0.372 --8107.860 jh ---------------- ------957 1080 98.4 < 1.44 --< 4.35 < 5.28 < 0.471 --3505.404 jh ---------------- ------120000 39600 24100 1330 --57800 23700 25.7 EMPC --394237.764 h ---------------- ------8990 3080 1260 EMPC 63.0 --1800 911 < 0.812 --17944.152 jh ---------------- ------3160000 479000 *308000 *9780 *--856000 264000 *153 --1609545.0 h ---------------- ------------------------------------------ ------------------------------------------ 229 13720 *808 *--------4270 ------76960 17290 13000 552 355 38 b 1425 222 174 5562 ------13800 3950 a 2260 a 427 a --4360 a 2000 a 1.62 a -------------------- ------13800 3620 a 2250 a 427 a --4360 a 2000 a 1.32 a -------------------- ------13800 3950 a 2260 a 429 a --4360 a 2000 a 3.47 a -------------------- ------13800 3620 a 2250 a 429 a --4360 a 2000 a 3.17 a -------------------- ------13800 3950 a 2260 a 428 a --4360 a 2000 a 2.55 a -------------------- ------13800 3620 a 2250 a 428 a --4360 a 2000 a 2.24 a -------------------- Table A-1 West Area Soil Quality Data Joslyn Manufacturing Supply Co. Brooklyn Center, Minnesota Page 7 of 15 10/26/2017 P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2017\Appendices\Appendix A\Table A-1 West Area_10032017.xlsx Parameter Analysis Location Units General Parameters Carbon, total organic Lab % pH Field pH units Solids, percent Lab % Solids, total Lab % SVOCs 1,6-Dinitropyrene Lab mg/kg 1,8-Dinitropyrene Lab mg/kg 1-Nitropyrene Lab mg/kg 2-Nitrofluorene Lab mg/kg 3-Methylcholanthrene Lab mg/kg 4-Nitropyrene Lab mg/kg 5-Methylchrysene Lab mg/kg 5-Nitroacenapthene Lab mg/kg 6-Nitrochrysene Lab mg/kg 7,12-Dimethylbenz(a)anthracene Lab mg/kg 7h-Dibenzo(c,g)carbazole Lab mg/kg Benz(a)anthracene Lab mg/kg Benzo(a)pyrene Lab mg/kg Benzo(b)fluoranthene Lab mg/kg Benzo(k)fluoranthene Lab mg/kg Chrysene Lab mg/kg Dibenz(a,h)acridine Lab mg/kg Dibenz(a,h)anthracene Lab mg/kg Dibenz(a,j)acridine Lab mg/kg Dibenzo(a,e)pyrene Lab mg/kg Dibenzo(a,h)pyrene Lab mg/kg Dibenzo(a,i)pyrene Lab mg/kg Dibenzo(a,l)pyrene Lab mg/kg Indeno(1,2,3-cd)pyrene Lab mg/kg B(a)P Equivalent, non-detects at 0, 2002 PEFs Calc mg/kg B(a)P Equivalent, non-detects at 1/2, 2002 PEFs Calc mg/kg B(a)P Equivalent, non-detects at 1x, 2002 PEFs Calc mg/kg 2-Chloronaphthalene Lab mg/kg 2-Methylnaphthalene Lab mg/kg Depth Location Sample Type Date C-3 0.5- 1.5' C-3 1.5- 2.5'C-3 2.5-4'C-3 C-3 C-3 C-3 C-3 C-4 C-5 C-5R C-5R D-1 D-1 D-1 D-1 D-2 D-3 0-0.5'D-3 0.5- 1.5' D-3 1.5- 2.5' 2/04/2003 2/04/2003 2/04/2003 4/21/2003 2/02/2015 2/02/2015 2/02/2015 2/02/2015 2/03/2003 2/03/2003 4/21/2003 4/21/2003 2/03/2003 2/02/2015 2/02/2015 2/02/2015 2/03/2003 2/04/2003 2/04/2003 2/04/2003 3.5 - 5 ft 5 - 6.5 ft 6.5 - 9 ft 9 - 10 ft 0.5 - 2 ft 2 - 3.5 ft 3.5 - 9 ft N N N N N N N N N N N N N N FD N N N N N N N 24.3 38.2 40.4 --39.4 40.2 h 32.2 h 7.33 h 23.8 9.06 --4.07 4.35 ----1.33 1.37 h 14.3 h 3.13 35.1 34.7 37.5 6.24 6.03 6.13 ----------6.30 6.87 --6.82 7.55 ----------6.59 6.07 6.38 6.74 20.8 20.9 21.7 ----------31.8 78.6 --81.5 83.8 ----------75.0 18.6 26.5 25.3 --------22.1 17.5 18.7 35.5 --------------87.8 84.2 39.9 -------- ------< 50.0 ------------< 20.0 ----< 20.0 < 20.0 < 20.0 -------------- ------< 50.0 ------------< 20.0 ----< 20.0 < 20.0 < 20.0 -------------- ------< 25.0 ------------< 10.0 ----< 10.0 < 10.0 < 10.0 -------------- ------< 25.0 ------------< 10.0 ----< 10.0 < 10.0 < 10.0 -------------- ------< 5.00 ------------< 2.00 ----< 2.00 < 2.00 < 2.00 -------------- ------< 25.0 ------------< 10.0 ----< 10.0 < 10.0 < 10.0 -------------- ------< 5.00 ------------41.9 ----ND pp ND pp ND pp -------------- ------< 25.0 ------------< 10.0 ----< 10.0 < 10.0 < 10.0 -------------- ------< 25.0 ------------< 10.0 ----< 10.0 < 10.0 < 10.0 -------------- ------< 5.00 ------------< 2.00 ----< 2.00 < 2.00 < 2.00 -------------- ------< 5.00 ------------< 2.00 ----< 2.00 < 2.00 < 2.00 -------------- 1.7 < 1.6 < 1.6 < 5.00 --------1.6 160 41.7 43 2.7 ND pp ND pp ND pp ------1.1 < 1.6 < 0.94 < 1.1 2.5 < 1.6 < 1.6 7.26 --------3.4 240 57.5 80 1.7 2.09 ND pp 2.24 ------1.2 < 1.6 < 0.94 < 1.1 11 < 1.6 < 1.6 8.10 c --------5.5 300 120 c 89 5.1 8.14 c 7.92 c 8.36 c ------2.8 < 1.6 < 0.94 < 1.1 4.6 < 1.6 < 1.6 8.10 c --------2.8 230 120 c 76 2.1 8.14 c 7.92 c 8.36 c ------1.5 < 1.6 < 0.94 < 1.1 4.4 < 1.6 < 1.6 < 5.00 --------3.6 320 49.6 68 3.9 3.63 3.47 3.79 ------2.4 < 1.6 < 0.94 < 1.1 ------< 5.00 ------------4.87 ----< 2.00 < 2.00 < 2.00 -------------- 1.8 < 1.6 < 1.6 < 5.00 --------< 0.95 49 17.8 23 0.53 < 2.00 < 2.00 < 2.00 ------< 0.38 < 1.6 < 0.94 < 1.1 ------< 5.00 ------------6.27 ----< 2.00 < 2.00 < 2.00 -------------- ------< 25.0 ------------< 10.0 ----< 10.0 < 10.0 < 10.0 -------------- ------< 25.0 ------------23.8 ----< 10.0 < 10.0 < 10.0 -------------- ------< 25.0 ------------< 10.0 ----< 10.0 < 10.0 < 10.0 -------------- ------< 25.0 ------------42.5 ----< 10.0 < 10.0 < 10.0 -------------- 8.5 < 1.6 < 1.6 2.5 pp --------2.5 140 39.4 53 1.7 ND pp ND pp ND pp ------1.2 < 1.6 < 0.94 < 1.1 6.1 ND ND ----------4.7 350 --120 3.2 ----------1.9 ND ND ND 6.1 1.6 1.6 ----------4.9 350 --120 3.2 ----------2.0 1.6 0.93 1.1 -------------------------------------------- < 1.6 < 1.6 < 1.6 ----------< 0.95 < 0.67 --< 0.66 < 0.33 ----------< 0.38 < 1.6 < 0.94 < 1.1 < 1.6 < 1.6 < 1.6 < 5.00 --------< 0.95 8.4 < 2.00 0.83 0.48 < 2.00 < 2.00 < 2.00 ------0.43 < 1.6 < 0.94 < 1.1 D-1 4/21/2003 Table A-1 West Area Soil Quality Data Joslyn Manufacturing Supply Co. Brooklyn Center, Minnesota Page 8 of 15 10/26/2017 P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2017\Appendices\Appendix A\Table A-1 West Area_10032017.xlsx Parameter Analysis Location Units Depth Location Sample Type Date Acenaphthene Lab mg/kg Acenaphthylene Lab mg/kg Anthracene Lab mg/kg B(a)P Equivalent, 1999 PEFs Lab mg/kg Benzo(e)pyrene Lab mg/kg Benzo(g,h,i)perylene Lab mg/kg Carbazole Lab mg/kg Fluoranthene Lab mg/kg Fluorene Lab mg/kg Naphthalene Lab mg/kg Pentachlorophenol Lab mg/kg Perylene Lab mg/kg Phenanthrene Lab mg/kg Pyrene Lab mg/kg Chlorinated Dioxins / Furans 2,3,7,8-Dioxin, tetra Lab ng/kg 1,2,3,7,8-Dioxin, penta Lab ng/kg 1,2,3,4,7,8-Dioxin, hexa Lab ng/kg 1,2,3,6,7,8-Dioxin, hexa Lab ng/kg 1,2,3,7,8,9-Dioxin, hexa Lab ng/kg 1,2,3,4,6,7,8-Dioxin, hepta Lab ng/kg Dioxin, octa Lab ng/kg 2,3,7,8-Dibenzofuran, tetra Lab ng/kg 1,2,3,7,8-Dibenzofuran, penta Lab ng/kg 2,3,4,7,8-Dibenzofuran, penta Lab ng/kg 1,2,3,4,7,8-Dibenzofuran, hexa Lab ng/kg 1,2,3,6,7,8-Dibenzofuran, hexa Lab ng/kg 2,3,4,6,7,8-Dibenzofuran, hexa Lab ng/kg 1,2,3,7,8,9-Dibenzofuran, hexa Lab ng/kg 1,2,3,4,6,7,8-Dibenzofuran, hepta Lab ng/kg 1,2,3,4,7,8,9-Dibenzofuran, hepta Lab ng/kg Dibenzofuran, octa Lab ng/kg TEQ DF WHO05 , non-detects at zero for the detection limit Calc ng/kg TEQ DF WHO05, non-detects at half of the detection limit Calc ng/kg Dioxin TEQ (by method 4425)Lab ng/kg TCDD Equivalent, reporting limit at 0, TEF 2005 (EMPC @ 1)Calc ng/kg TCDD Equivalent, reporting limit at 0, TEF 2005 (EMPC @ 1/2)Calc ng/kg TCDD Equivalent, reporting limit at 1, TEF 2005 (EMPC @ 1)Calc ng/kg TCDD Equivalent, reporting limit at 1, TEF 2005 (EMPC @ 1/2)Calc ng/kg TCDD Equivalent, reporting limit at 1/2, TEF 2005 (EMPC @ 1)Calc ng/kg TCDD Equivalent, reporting limit at 1/2, TEF 2005 (EMPC@1/2)Calc ng/kg C-3 0.5- 1.5' C-3 1.5- 2.5'C-3 2.5-4'C-3 C-3 C-3 C-3 C-3 C-4 C-5 C-5R C-5R D-1 D-1 D-1 D-1 D-2 D-3 0-0.5'D-3 0.5- 1.5' D-3 1.5- 2.5' 2/04/2003 2/04/2003 2/04/2003 4/21/2003 2/02/2015 2/02/2015 2/02/2015 2/02/2015 2/03/2003 2/03/2003 4/21/2003 4/21/2003 2/03/2003 2/02/2015 2/02/2015 2/02/2015 2/03/2003 2/04/2003 2/04/2003 2/04/2003 3.5 - 5 ft 5 - 6.5 ft 6.5 - 9 ft 9 - 10 ft 0.5 - 2 ft 2 - 3.5 ft 3.5 - 9 ft N N N N N N N N N N N N N N FD N N N N N N N D-1 4/21/2003 < 1.6 < 1.6 < 1.6 < 5.00 --------< 0.95 22 < 2.00 < 0.66 < 0.33 < 2.00 < 2.00 < 2.00 ------< 0.38 < 1.6 < 0.94 < 1.1 < 1.6 < 1.6 < 1.6 < 5.00 --------< 0.95 2.2 7.02 1.1 < 0.33 < 2.00 < 2.00 < 2.00 ------< 0.38 < 1.6 < 0.94 < 1.1 2.4 < 1.6 < 1.6 8.92 --------< 0.95 99 17.9 11 0.64 3.11 3.18 3.04 ------11 < 1.6 < 0.94 < 1.1 -------------------------------------------- ------< 5.00 ------------83.7 ----3.32 3.23 3.41 -------------- 7.8 < 1.6 < 1.6 5.06 --------2.2 120 42.6 53 1.6 ND pp ND pp 2.01 ------1.0 < 1.6 < 0.94 < 1.1 ------2.5 pp ------------2.67 ----ND pp ND pp ND pp -------------- 3.6 < 1.6 < 1.6 < 5.00 --------1.3 150 20.5 25 6.2 3.87 3.94 3.79 ------1.6 < 1.6 < 0.94 < 1.1 < 1.6 < 1.6 < 1.6 < 5.00 --------< 0.95 24 1.00 pp 0.89 < 0.33 < 2.00 < 2.00 < 2.00 ------0.71 < 1.6 < 0.94 < 1.1 < 1.6 < 1.6 < 1.6 < 5.00 --------< 0.95 12 1.00 pp 2.0 0.53 < 2.00 < 2.00 < 2.00 ------< 0.38 < 1.6 < 0.94 < 1.1 62 13 < 9.3 450 --------< 5.8 < 4.1 < 10.0 < 4.0 77 227 238 215 ------23 9.2 < 5.7 < 6.5 ------< 5.00 ------------17.5 ----< 2.00 < 2.00 < 2.00 -------------- < 1.6 < 1.6 < 1.6 < 5.00 --------< 0.95 110 6.86 4.7 1.6 2.69 2.65 2.73 ------1.9 < 1.6 < 0.94 < 1.1 4.8 < 1.6 < 1.6 < 5.00 --------1.8 180 51.0 48 9.1 5.09 5.16 5.03 ------2.2 2.1 < 0.94 < 1.1 --------< 0.156 2.04 EMPC < 2.50 < 0.224 --------------24.1 1.88 EMPC < 0.824 -------- --------11.8 104 29.4 0.268 EMPC --------------521 32.0 1.72 EMPC -------- --------79.0 501 111 1.11 EMPC --------------1700 171 7.17 -------- --------6270 18500 1280 8.76 --------------21400 2180 52.3 -------- --------385 1100 284 1.78 j --------------4160 359 13.5 EMPC -------- --------290000 382000 *73200 351 --------------650000 52000 *1860 -------- --------5390000 4450000 *725000 3750 --------------5200000 684000 *25300 e -------- --------61.3 327 17.3 EMPC < 0.291 --------------201 5.36 < 0.863 -------- --------411 2350 85.6 0.700 j --------------950 25.7 3.03 EMPC -------- --------3.39 j 4770 200 1.22 j --------------3090 138 5.14 j -------- --------3630 20500 890 4.90 j --------------16800 1000 41.6 -------- --------741 4370 205 1.45 j --------------3170 195 9.58 EMPC -------- --------1230 6410 344 2.34 j --------------5320 328 13.5 -------- --------1400 7660 288 1.71 j --------------4190 101 10.5 -------- --------141000 171000 35600 101 --------------151000 22700 547 -------- --------5500 16900 1060 5.89 j --------------15400 2020 38.0 -------- --------1850000 1290000 *147000 571 --------------2800000 180000 *2750 -------- -------------------------------------------- -------------------------------------------- 3003 756 766 ----------493 829 --1126 9010 ----------2850 7810 4920 666 --------7940 a 15000 a 1790 a 8.74 a --------------17800 1540 a 51 a -------- --------7940 a 15000 a 1790 a 8.55 a --------------17800 1540 a 49 a -------- --------7940 a 15000 a 1800 a 8.99 a --------------17800 1540 a 51.9 a -------- --------7940 a 15000 a 1800 a 8.8 a --------------17800 1540 a 49.9 a -------- --------7940 a 15000 a 1800 a 8.86 a --------------17800 1540 a 51.5 a -------- --------7940 a 15000 a 1790 a 8.67 a --------------17800 1540 a 49.4 a -------- Table A-1 West Area Soil Quality Data Joslyn Manufacturing Supply Co. Brooklyn Center, Minnesota Page 9 of 15 10/26/2017 P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2017\Appendices\Appendix A\Table A-1 West Area_10032017.xlsx Parameter Analysis Location Units General Parameters Carbon, total organic Lab % pH Field pH units Solids, percent Lab % Solids, total Lab % SVOCs 1,6-Dinitropyrene Lab mg/kg 1,8-Dinitropyrene Lab mg/kg 1-Nitropyrene Lab mg/kg 2-Nitrofluorene Lab mg/kg 3-Methylcholanthrene Lab mg/kg 4-Nitropyrene Lab mg/kg 5-Methylchrysene Lab mg/kg 5-Nitroacenapthene Lab mg/kg 6-Nitrochrysene Lab mg/kg 7,12-Dimethylbenz(a)anthracene Lab mg/kg 7h-Dibenzo(c,g)carbazole Lab mg/kg Benz(a)anthracene Lab mg/kg Benzo(a)pyrene Lab mg/kg Benzo(b)fluoranthene Lab mg/kg Benzo(k)fluoranthene Lab mg/kg Chrysene Lab mg/kg Dibenz(a,h)acridine Lab mg/kg Dibenz(a,h)anthracene Lab mg/kg Dibenz(a,j)acridine Lab mg/kg Dibenzo(a,e)pyrene Lab mg/kg Dibenzo(a,h)pyrene Lab mg/kg Dibenzo(a,i)pyrene Lab mg/kg Dibenzo(a,l)pyrene Lab mg/kg Indeno(1,2,3-cd)pyrene Lab mg/kg B(a)P Equivalent, non-detects at 0, 2002 PEFs Calc mg/kg B(a)P Equivalent, non-detects at 1/2, 2002 PEFs Calc mg/kg B(a)P Equivalent, non-detects at 1x, 2002 PEFs Calc mg/kg 2-Chloronaphthalene Lab mg/kg 2-Methylnaphthalene Lab mg/kg Depth Location Sample Type Date D-3 2.5-4'D-4 D-5 E-1 E-2 E-3 E-3 E-4 E-4 E-4 E-4 F-1 F-2 F-3 F-3 F-3 F-3 F-3 G-1 2/04/2003 2/03/2003 1/20/2003 1/20/2003 1/20/2003 1/20/2003 4/21/2003 2/02/2015 2/02/2015 2/02/2015 2/02/2015 1/20/2003 1/20/2003 1/20/2003 2/02/2015 2/02/2015 2/02/2015 2/02/2015 1/20/2003 3.5 - 5 ft 5 - 6.5 ft 6.5 - 9 ft 9 - 10 ft 2.5 - 4 ft 4 - 5.5 ft 5.5 - 9 ft 9 - 10 ft N N N N N N N N N N N N N N N N N N N FD N 38.3 26.6 28.9 6.01 34.1 40.6 --44.3 31.9 h 8.01 h 3.91 h 4.80 8.72 39.1 11.0 17.9 h 38.4 h 11.8 h 39.4 39.9 1.12 6.83 7.18 7.22 6.78 5.84 6.35 ----------7.58 7.31 5.77 --------6.32 6.30 7.88 23.7 29.4 14.9 47.6 7.19 16.4 ----------79.1 55.5 8.67 --------9.64 10.3 83.5 --------------22.0 16.5 32.9 40.8 ------31.3 25.8 13.4 30.6 ------ ------------< 10.0 ---------------------------- ------------< 10.0 ---------------------------- ------------< 5.00 ---------------------------- ------------< 5.00 ---------------------------- ------------< 1.00 ---------------------------- ------------< 5.00 ---------------------------- ------------< 1.00 ---------------------------- ------------< 5.00 ---------------------------- ------------< 5.00 ---------------------------- ------------< 1.00 ---------------------------- ------------< 1.00 ---------------------------- < 2.2 < 0.84 < 2.3 < 0.70 < 4.6 < 41 < 1.00 ------------< 3.8 --------< 3.5 < 3.2 < 0.40 < 2.2 < 0.84 < 2.3 < 0.70 < 4.6 < 41 < 1.00 ------------< 3.8 --------< 3.5 < 3.2 < 0.40 < 2.2 < 0.84 < 2.3 1.1 < 4.6 99 < 1.00 ------------< 3.8 --------< 3.5 < 3.2 < 0.40 < 2.2 < 0.84 < 2.3 0.71 < 4.6 < 41 < 1.00 ------------< 3.8 --------< 3.5 < 3.2 < 0.40 < 2.2 < 0.84 < 2.3 0.82 < 4.6 < 41 < 1.00 ------------< 3.8 --------< 3.5 < 3.2 < 0.40 ------------< 1.00 ---------------------------- < 2.2 < 0.84 < 2.3 < 0.71 < 4.7 < 41 < 1.00 ------------< 3.9 --------< 3.5 < 3.3 < 0.40 ------------< 1.00 ---------------------------- ------------< 5.00 ---------------------------- ------------< 5.00 ---------------------------- ------------< 5.00 ---------------------------- ------------< 5.00 ---------------------------- < 2.2 < 0.84 < 2.3 < 0.71 < 4.7 97 < 1.00 ------------< 3.9 --------< 3.5 < 3.3 < 0.40 ND ND ND 0.19 ND 20 --------------ND --------ND --ND 2.2 0.83 2.3 0.81 4.6 56 --------------3.8 --------3.4 --0.39 ------------------------------------------ < 2.2 < 0.84 < 2.3 < 0.70 < 4.6 < 8.1 --------------< 3.8 --------< 3.5 < 3.2 < 0.40 < 2.2 < 0.84 < 2.3 < 0.70 < 4.6 < 8.1 < 1.00 ------------< 3.8 --------< 3.5 < 3.2 < 0.40 1/20/2003 F-4 Table A-1 West Area Soil Quality Data Joslyn Manufacturing Supply Co. Brooklyn Center, Minnesota Page 10 of 15 10/26/2017 P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2017\Appendices\Appendix A\Table A-1 West Area_10032017.xlsx Parameter Analysis Location Units Depth Location Sample Type Date Acenaphthene Lab mg/kg Acenaphthylene Lab mg/kg Anthracene Lab mg/kg B(a)P Equivalent, 1999 PEFs Lab mg/kg Benzo(e)pyrene Lab mg/kg Benzo(g,h,i)perylene Lab mg/kg Carbazole Lab mg/kg Fluoranthene Lab mg/kg Fluorene Lab mg/kg Naphthalene Lab mg/kg Pentachlorophenol Lab mg/kg Perylene Lab mg/kg Phenanthrene Lab mg/kg Pyrene Lab mg/kg Chlorinated Dioxins / Furans 2,3,7,8-Dioxin, tetra Lab ng/kg 1,2,3,7,8-Dioxin, penta Lab ng/kg 1,2,3,4,7,8-Dioxin, hexa Lab ng/kg 1,2,3,6,7,8-Dioxin, hexa Lab ng/kg 1,2,3,7,8,9-Dioxin, hexa Lab ng/kg 1,2,3,4,6,7,8-Dioxin, hepta Lab ng/kg Dioxin, octa Lab ng/kg 2,3,7,8-Dibenzofuran, tetra Lab ng/kg 1,2,3,7,8-Dibenzofuran, penta Lab ng/kg 2,3,4,7,8-Dibenzofuran, penta Lab ng/kg 1,2,3,4,7,8-Dibenzofuran, hexa Lab ng/kg 1,2,3,6,7,8-Dibenzofuran, hexa Lab ng/kg 2,3,4,6,7,8-Dibenzofuran, hexa Lab ng/kg 1,2,3,7,8,9-Dibenzofuran, hexa Lab ng/kg 1,2,3,4,6,7,8-Dibenzofuran, hepta Lab ng/kg 1,2,3,4,7,8,9-Dibenzofuran, hepta Lab ng/kg Dibenzofuran, octa Lab ng/kg TEQ DF WHO05 , non-detects at zero for the detection limit Calc ng/kg TEQ DF WHO05, non-detects at half of the detection limit Calc ng/kg Dioxin TEQ (by method 4425)Lab ng/kg TCDD Equivalent, reporting limit at 0, TEF 2005 (EMPC @ 1)Calc ng/kg TCDD Equivalent, reporting limit at 0, TEF 2005 (EMPC @ 1/2)Calc ng/kg TCDD Equivalent, reporting limit at 1, TEF 2005 (EMPC @ 1)Calc ng/kg TCDD Equivalent, reporting limit at 1, TEF 2005 (EMPC @ 1/2)Calc ng/kg TCDD Equivalent, reporting limit at 1/2, TEF 2005 (EMPC @ 1)Calc ng/kg TCDD Equivalent, reporting limit at 1/2, TEF 2005 (EMPC@1/2)Calc ng/kg D-3 2.5-4'D-4 D-5 E-1 E-2 E-3 E-3 E-4 E-4 E-4 E-4 F-1 F-2 F-3 F-3 F-3 F-3 F-3 G-1 2/04/2003 2/03/2003 1/20/2003 1/20/2003 1/20/2003 1/20/2003 4/21/2003 2/02/2015 2/02/2015 2/02/2015 2/02/2015 1/20/2003 1/20/2003 1/20/2003 2/02/2015 2/02/2015 2/02/2015 2/02/2015 1/20/2003 3.5 - 5 ft 5 - 6.5 ft 6.5 - 9 ft 9 - 10 ft 2.5 - 4 ft 4 - 5.5 ft 5.5 - 9 ft 9 - 10 ft N N N N N N N N N N N N N N N N N N N FD N 1/20/2003 F-4 < 2.2 < 0.84 < 2.3 < 0.70 < 4.6 < 8.1 < 1.00 ------------< 3.8 --------< 3.5 < 3.2 < 0.40 < 2.2 < 0.84 < 2.3 < 0.70 < 4.6 < 8.1 < 1.00 ------------< 3.8 --------< 3.5 < 3.2 < 0.40 < 2.2 < 0.84 < 2.3 < 0.70 < 4.6 14 0.50 pp ------------< 3.8 --------< 3.5 < 3.2 < 0.40 ------------------------------------------ ------------< 1.00 ---------------------------- < 2.2 < 0.84 < 2.3 < 0.71 < 4.7 100 < 1.00 ------------< 3.9 --------< 3.5 < 3.3 < 0.40 ------------< 1.00 ---------------------------- < 2.2 < 0.84 < 2.3 0.87 < 4.6 35 < 1.00 ------------< 3.8 --------< 3.5 < 3.2 < 0.40 < 2.2 < 0.84 < 2.3 < 0.70 < 4.6 < 8.1 < 1.00 ------------< 3.8 --------< 3.5 < 3.2 < 0.40 < 2.2 < 0.84 < 2.3 < 0.70 < 4.6 < 8.1 < 1.00 ------------< 3.8 --------< 3.5 < 3.2 < 0.40 < 14 < 5.1 < 14 7.5 < 28 77 < 5.00 --------< 2.6 4.6 < 24 --------< 21 < 20 < 2.4 ------------< 1.00 ---------------------------- < 2.2 < 0.84 < 2.3 < 0.70 < 4.6 < 8.1 < 1.00 ------------< 3.8 --------< 3.5 < 3.2 < 0.40 < 2.2 < 0.84 < 2.3 0.92 < 4.6 74 < 1.00 ------------< 3.8 --------< 3.5 < 3.2 < 0.40 ----< 1.0 ----140.802 j --6.54 3.80 EMPC 47.2 < 1.47 ------21.6 26.5 17.7 < 0.298 ------ ----0.628 j ----2003.655 --66.4 55.3 124 35.9 EMPC ------119 190 98.3 0.850 j ------ ----1.613 j ----10035.896 --164 275 31.6 184 ------538 547 265 0.826 EMPC ------ ----29.186 ----69659.364 --634 1050 279 2050 ------2560 2440 480 2.63 EMPC ------ ----5.946 ----33422.315 b --487 407 54.1 168 ------995 800 301 1.37 j ------ ----1156.072 ----2442188.8 eb --40500 55100 *22500 *232000 *------122000 72000 *11500 62.7 ------ ----8082.694 eb ----5830616.8 e --366000 397000 *134000 *2220000 *------1450000 602000 *145000 685 ------ ----1.208 jc ----81.296 j --6.36 < 2.91 40.7 < 1.17 ------27.0 28.9 EMPC 18.6 EMPC < 0.312 ------ ----1.623 j ----396.863 j --34.2 34.1 123 1.66 EMPC ------75.4 88.3 61.2 1.01 EMPC ------ ----6.145 ----187.590 j --25.8 75.2 2.66 j < 3.02 ------179 237 136 0.732 j ------ ----32.754 ----10050.701 b --260 316 21.7 170 *------720 *847 379 1.53 j ------ ----4.254 jEMPC ----2324.595 --72.5 81.5 72.7 30.3 *------330 290 106 0.844 EMPC ------ ----7.749 ----5274.657 --112 141 9.92 64.8 ------473 186 EMPC 162 1.08 j ------ ----5.520 ----< 2.5 --144 85.2 *< 4.22 *< 31.5 ------358 258 *164 1.57 j ------ ----333.079 ----642346.511 e --3730 7290 1350 12400 j*------30700 17800 3150 16.7 ------ ----13.245 ----23567.064 --279 422 67.9 533 *------1220 1270 298 2.02 j ------ ----2018.758 ----3021912.8 eb --29900 29300 EMPC*9360 *91700 *------228000 91300 *7960 106 ------ ------------------------------------------ ------------------------------------------ 223 448 25 5440 1624 38110 ----------64 440 2300 --------586 285 101 --------------834 1070 a 509 a 3450 a ------2840 a 1950 a 542 a 3.14 a ------ --------------834 1070 a 509 a 3430 a ------2840 a 1940 a 541 a 2.91 a ------ --------------834 1070 a 509 a 3450 a ------2840 a 1950 a 542 a 3.47 a ------ --------------834 1070 a 509 a 3430 a ------2840 a 1940 a 541 a 3.24 a ------ --------------834 1070 a 509 a 3450 a ------2840 a 1950 a 542 a 3.3 a ------ --------------834 1070 a 509 a 3430 a ------2840 a 1940 a 541 a 3.07 a ------ Table A-1 West Area Soil Quality Data Joslyn Manufacturing Supply Co. Brooklyn Center, Minnesota Page 11 of 15 10/26/2017 P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2017\Appendices\Appendix A\Table A-1 West Area_10032017.xlsx Parameter Analysis Location Units General Parameters Carbon, total organic Lab % pH Field pH units Solids, percent Lab % Solids, total Lab % SVOCs 1,6-Dinitropyrene Lab mg/kg 1,8-Dinitropyrene Lab mg/kg 1-Nitropyrene Lab mg/kg 2-Nitrofluorene Lab mg/kg 3-Methylcholanthrene Lab mg/kg 4-Nitropyrene Lab mg/kg 5-Methylchrysene Lab mg/kg 5-Nitroacenapthene Lab mg/kg 6-Nitrochrysene Lab mg/kg 7,12-Dimethylbenz(a)anthracene Lab mg/kg 7h-Dibenzo(c,g)carbazole Lab mg/kg Benz(a)anthracene Lab mg/kg Benzo(a)pyrene Lab mg/kg Benzo(b)fluoranthene Lab mg/kg Benzo(k)fluoranthene Lab mg/kg Chrysene Lab mg/kg Dibenz(a,h)acridine Lab mg/kg Dibenz(a,h)anthracene Lab mg/kg Dibenz(a,j)acridine Lab mg/kg Dibenzo(a,e)pyrene Lab mg/kg Dibenzo(a,h)pyrene Lab mg/kg Dibenzo(a,i)pyrene Lab mg/kg Dibenzo(a,l)pyrene Lab mg/kg Indeno(1,2,3-cd)pyrene Lab mg/kg B(a)P Equivalent, non-detects at 0, 2002 PEFs Calc mg/kg B(a)P Equivalent, non-detects at 1/2, 2002 PEFs Calc mg/kg B(a)P Equivalent, non-detects at 1x, 2002 PEFs Calc mg/kg 2-Chloronaphthalene Lab mg/kg 2-Methylnaphthalene Lab mg/kg Depth Location Sample Type Date G-2 G-3 0-0.5'G-3 0.5- 1.5' G-3 1.5- 2.5'G-3 2.5-4'G-3 H-3 G-4 0-0.5'G-4 0.5-1.5'G-4 0.5-1.5'G-4 1.5- 2.5'G-4 2.5-4'G-5 0-0.5'G-5 0.5- 1.5' G-5 1.5- 2.5'G-5 2.5-4'H-1 H-2 H-4 2/04/2003 1/21/2003 1/21/2003 1/21/2003 1/21/2003 12/04/1998 1/21/2003 1/20/2003 1/21/2003 1/21/2003 1/21/2003 1/21/2003 1/21/2003 1/21/2003 1/21/2003 1/20/2003 1/20/2003 2/04/2003 N N N N N N N N N N N N N N N N N N FD N N FD 0.95 35.2 35.4 40.2 40.1 --40.2 --31.7 32.0 4.33 35.3 30.0 10.8 4.70 0.96 5.16 2.61 2.46 6.45 38.3 34.5 7.71 6.16 6.19 6.19 6.93 --6.62 --6.26 6.53 7.16 7.05 7.19 7.38 7.43 7.43 7.00 7.39 7.27 9.98 6.06 6.07 85.2 7.43 7.72 11.8 13.2 --8.05 --19.8 21.4 43.3 7.49 11.4 33.6 52.8 81.1 66.1 76.7 77.9 74.8 11.8 12.6 ----------84 -------------------------------- -------------------------------------------- -------------------------------------------- -------------------------------------------- -------------------------------------------- -------------------------------------------- -------------------------------------------- -------------------------------------------- -------------------------------------------- -------------------------------------------- -------------------------------------------- -------------------------------------------- 0.49 < 4.5 < 4.3 < 2.8 < 2.5 0.64 < 4.1 --< 1.7 < 1.6 < 0.77 < 4.5 < 2.9 < 0.99 < 0.63 < 0.41 1.7 0.58 0.40 < 1.7 < 2.8 < 2.7 0.47 < 4.5 < 4.3 < 2.8 < 2.5 1.0 < 4.1 --< 1.7 < 1.6 < 0.77 < 4.5 < 2.9 < 0.99 < 0.63 0.43 < 5.0 < 1.7 < 1.7 < 1.7 < 2.8 < 2.7 0.70 < 4.5 < 4.3 < 2.8 < 2.5 1.8 < 4.1 --< 1.7 < 1.6 < 0.77 < 4.5 < 2.9 < 0.99 < 0.63 < 0.41 < 5.0 < 1.7 < 1.7 < 1.7 < 2.8 < 2.7 0.48 < 4.5 < 4.3 < 2.8 < 2.5 0.76 < 4.1 --< 1.7 < 1.6 < 0.77 < 4.5 < 2.9 < 0.99 < 0.63 < 0.41 < 5.0 < 1.7 < 1.7 < 1.7 < 2.8 < 2.7 0.64 < 4.5 < 4.3 < 2.8 < 2.5 0.78 < 4.1 --< 1.7 < 1.6 < 0.77 < 4.5 < 2.9 < 0.99 < 0.63 0.44 1.8 0.77 0.55 < 1.7 < 2.8 < 2.7 -------------------------------------------- < 0.33 < 4.5 < 4.3 < 2.8 < 2.5 < 0.33 < 4.2 --< 1.7 < 1.6 < 0.77 < 4.5 < 3.0 < 0.99 < 0.63 < 0.42 < 5.0 < 1.7 < 1.7 < 1.7 < 2.9 < 2.7 -------------------------------------------- -------------------------------------------- -------------------------------------------- -------------------------------------------- -------------------------------------------- 0.37 < 4.5 < 4.3 < 2.8 < 2.5 < 0.33 < 4.2 --< 1.7 < 1.6 < 0.77 < 4.5 < 3.0 < 0.99 < 0.63 < 0.42 < 5.0 < 1.7 < 1.7 < 1.7 < 2.9 < 2.7 0.68 ND ND ND ND --ND --ND ND ND ND ND ND ND 0.43 0.19 0.066 --ND ND -- 0.77 4.4 4.2 2.8 2.5 --4.1 --1.7 1.6 0.76 4.4 2.9 0.98 0.62 0.63 4.8 1.6 --1.7 2.8 -- -------------------------------------------- < 0.33 < 4.5 < 4.3 < 2.8 < 2.5 < 0.33 < 4.1 --< 1.7 < 1.6 < 0.77 < 4.5 < 2.9 < 0.99 < 0.63 < 0.41 < 0.50 < 0.33 < 0.33 < 0.33 < 2.8 < 2.7 < 0.33 < 4.5 < 4.3 < 2.8 < 2.5 < 0.33 < 4.1 --< 1.7 < 1.6 < 0.77 < 4.5 < 2.9 < 0.99 < 0.63 < 0.41 < 0.50 < 0.33 < 0.33 < 0.33 < 2.8 < 2.7 H-3 H-5 2/04/2003 1/20/2003 Table A-1 West Area Soil Quality Data Joslyn Manufacturing Supply Co. Brooklyn Center, Minnesota Page 12 of 15 10/26/2017 P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2017\Appendices\Appendix A\Table A-1 West Area_10032017.xlsx Parameter Analysis Location Units Depth Location Sample Type Date Acenaphthene Lab mg/kg Acenaphthylene Lab mg/kg Anthracene Lab mg/kg B(a)P Equivalent, 1999 PEFs Lab mg/kg Benzo(e)pyrene Lab mg/kg Benzo(g,h,i)perylene Lab mg/kg Carbazole Lab mg/kg Fluoranthene Lab mg/kg Fluorene Lab mg/kg Naphthalene Lab mg/kg Pentachlorophenol Lab mg/kg Perylene Lab mg/kg Phenanthrene Lab mg/kg Pyrene Lab mg/kg Chlorinated Dioxins / Furans 2,3,7,8-Dioxin, tetra Lab ng/kg 1,2,3,7,8-Dioxin, penta Lab ng/kg 1,2,3,4,7,8-Dioxin, hexa Lab ng/kg 1,2,3,6,7,8-Dioxin, hexa Lab ng/kg 1,2,3,7,8,9-Dioxin, hexa Lab ng/kg 1,2,3,4,6,7,8-Dioxin, hepta Lab ng/kg Dioxin, octa Lab ng/kg 2,3,7,8-Dibenzofuran, tetra Lab ng/kg 1,2,3,7,8-Dibenzofuran, penta Lab ng/kg 2,3,4,7,8-Dibenzofuran, penta Lab ng/kg 1,2,3,4,7,8-Dibenzofuran, hexa Lab ng/kg 1,2,3,6,7,8-Dibenzofuran, hexa Lab ng/kg 2,3,4,6,7,8-Dibenzofuran, hexa Lab ng/kg 1,2,3,7,8,9-Dibenzofuran, hexa Lab ng/kg 1,2,3,4,6,7,8-Dibenzofuran, hepta Lab ng/kg 1,2,3,4,7,8,9-Dibenzofuran, hepta Lab ng/kg Dibenzofuran, octa Lab ng/kg TEQ DF WHO05 , non-detects at zero for the detection limit Calc ng/kg TEQ DF WHO05, non-detects at half of the detection limit Calc ng/kg Dioxin TEQ (by method 4425)Lab ng/kg TCDD Equivalent, reporting limit at 0, TEF 2005 (EMPC @ 1)Calc ng/kg TCDD Equivalent, reporting limit at 0, TEF 2005 (EMPC @ 1/2)Calc ng/kg TCDD Equivalent, reporting limit at 1, TEF 2005 (EMPC @ 1)Calc ng/kg TCDD Equivalent, reporting limit at 1, TEF 2005 (EMPC @ 1/2)Calc ng/kg TCDD Equivalent, reporting limit at 1/2, TEF 2005 (EMPC @ 1)Calc ng/kg TCDD Equivalent, reporting limit at 1/2, TEF 2005 (EMPC@1/2)Calc ng/kg G-2 G-3 0-0.5'G-3 0.5- 1.5' G-3 1.5- 2.5'G-3 2.5-4'G-3 H-3 G-4 0-0.5'G-4 0.5-1.5'G-4 0.5-1.5'G-4 1.5- 2.5'G-4 2.5-4'G-5 0-0.5'G-5 0.5- 1.5' G-5 1.5- 2.5'G-5 2.5-4'H-1 H-2 H-4 2/04/2003 1/21/2003 1/21/2003 1/21/2003 1/21/2003 12/04/1998 1/21/2003 1/20/2003 1/21/2003 1/21/2003 1/21/2003 1/21/2003 1/21/2003 1/21/2003 1/21/2003 1/20/2003 1/20/2003 2/04/2003 N N N N N N N N N N N N N N N N N N FD N N FD H-3 H-5 2/04/2003 1/20/2003 < 0.33 < 4.5 < 4.3 < 2.8 < 2.5 < 0.33 < 4.1 --< 1.7 < 1.6 < 0.77 < 4.5 < 2.9 < 0.99 < 0.63 < 0.41 < 0.50 < 0.33 < 0.33 < 0.33 < 2.8 < 2.7 < 0.33 < 4.5 < 4.3 < 2.8 < 2.5 < 0.33 < 4.1 --< 1.7 < 1.6 < 0.77 < 4.5 < 2.9 < 0.99 < 0.63 < 0.41 < 0.50 < 0.33 < 0.33 < 0.33 < 2.8 < 2.7 0.69 < 4.5 < 4.3 < 2.8 < 2.5 < 0.33 < 4.1 --< 1.7 < 1.6 < 0.77 < 4.5 < 2.9 < 0.99 < 0.63 < 0.41 0.62 0.89 1.2 < 0.33 < 2.8 < 2.7 -------------------------------------------- -------------------------------------------- 0.34 < 4.5 < 4.3 < 2.8 < 2.5 < 0.33 < 4.2 --< 1.7 < 1.6 < 0.77 < 4.5 < 3.0 < 0.99 < 0.63 < 0.42 < 5.0 < 1.7 < 1.7 < 1.7 < 2.9 < 2.7 -------------------------------------------- 0.97 < 4.5 < 4.3 < 2.8 < 2.5 0.91 < 4.1 --< 1.7 < 1.6 < 0.77 < 4.5 < 2.9 < 0.99 < 0.63 0.47 3.0 1.2 0.68 < 0.33 < 2.8 < 2.7 < 0.33 < 4.5 < 4.3 < 2.8 < 2.5 < 0.33 < 4.1 --< 1.7 < 1.6 < 0.77 < 4.5 < 2.9 < 0.99 < 0.63 < 0.41 < 0.50 < 0.33 < 0.33 < 0.33 < 2.8 < 2.7 < 0.33 < 4.5 < 4.3 < 2.8 < 2.5 < 0.33 < 4.1 --< 1.7 < 1.6 < 0.77 < 4.5 < 2.9 < 0.99 < 0.63 < 0.41 < 0.50 < 0.33 < 0.33 < 0.33 < 2.8 < 2.7 3.3 < 27 < 26 < 17 < 16 1.0 < 25 --< 11 < 9.4 < 4.7 < 27 < 18 < 6.0 < 3.8 < 2.5 < 3.1 < 2.0 < 2.0 < 2.0 < 17 < 16 -------------------------------------------- 0.94 < 4.5 < 4.3 < 2.8 < 2.5 < 0.33 < 4.1 --< 1.7 < 1.6 < 0.77 < 4.5 < 2.9 < 0.99 < 0.63 < 0.41 2.7 1.2 0.63 < 0.33 < 2.8 < 2.7 1.0 < 4.5 < 4.3 < 2.8 < 2.5 1.1 < 4.1 --< 1.7 < 1.6 < 0.77 < 4.5 < 2.9 < 0.99 < 0.63 0.71 3.5 1.7 1.2 < 1.7 < 2.8 < 2.7 --------------< 1.0 ----------------< 1.0 ---------- --------------14.206 j ----------------11.183 j ---------- --------------48.588 ----------------25.260 j ---------- --------------246.881 ----------------295.504 ---------- --------------104.928 ----------------77.656 ---------- --------------8658.012 b ----------------7855.079 ---------- --------------61751.673 eb ----------------61893.534 eb ---------- --------------12.805 jc ----------------39.043 jc ---------- --------------36.098 ----------------51.525 ---------- --------------21.062 j ----------------42.979 ---------- --------------225.651 b ----------------310.538 ---------- --------------69.542 ----------------79.983 ---------- --------------105.359 ----------------133.655 ---------- --------------75.530 ----------------96.315 EMPC ---------- --------------2426.956 ----------------2551.074 ---------- --------------169.898 ----------------229.146 ---------- --------------6130.769 b ----------------5278.028 ---------- -------------------------------------------- -------------------------------------------- 171 774 1791 94 64 --270 --723 114 <5 523 850 643 28 102 306 62 *42 b*59 534 465 -------------------------------------------- -------------------------------------------- -------------------------------------------- -------------------------------------------- -------------------------------------------- -------------------------------------------- Table A-1 West Area Soil Quality Data Joslyn Manufacturing Supply Co. Brooklyn Center, Minnesota Page 13 of 15 10/26/2017 P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2017\Appendices\Appendix A\Table A-1 West Area_10032017.xlsx Parameter Analysis Location Units General Parameters Carbon, total organic Lab % pH Field pH units Solids, percent Lab % Solids, total Lab % SVOCs 1,6-Dinitropyrene Lab mg/kg 1,8-Dinitropyrene Lab mg/kg 1-Nitropyrene Lab mg/kg 2-Nitrofluorene Lab mg/kg 3-Methylcholanthrene Lab mg/kg 4-Nitropyrene Lab mg/kg 5-Methylchrysene Lab mg/kg 5-Nitroacenapthene Lab mg/kg 6-Nitrochrysene Lab mg/kg 7,12-Dimethylbenz(a)anthracene Lab mg/kg 7h-Dibenzo(c,g)carbazole Lab mg/kg Benz(a)anthracene Lab mg/kg Benzo(a)pyrene Lab mg/kg Benzo(b)fluoranthene Lab mg/kg Benzo(k)fluoranthene Lab mg/kg Chrysene Lab mg/kg Dibenz(a,h)acridine Lab mg/kg Dibenz(a,h)anthracene Lab mg/kg Dibenz(a,j)acridine Lab mg/kg Dibenzo(a,e)pyrene Lab mg/kg Dibenzo(a,h)pyrene Lab mg/kg Dibenzo(a,i)pyrene Lab mg/kg Dibenzo(a,l)pyrene Lab mg/kg Indeno(1,2,3-cd)pyrene Lab mg/kg B(a)P Equivalent, non-detects at 0, 2002 PEFs Calc mg/kg B(a)P Equivalent, non-detects at 1/2, 2002 PEFs Calc mg/kg B(a)P Equivalent, non-detects at 1x, 2002 PEFs Calc mg/kg 2-Chloronaphthalene Lab mg/kg 2-Methylnaphthalene Lab mg/kg Depth Location Sample Type Date I-1 I-2 0-0.5'I-2 0.5-1.5'I-2 1.5-2.5'I-2 2.5-4'I-3 J-1 J-2 J-3 1/20/2003 1/20/2003 1/20/2003 1/20/2003 1/20/2003 1/20/2003 1/20/2003 1/20/2003 1/20/2003 N N N N N N N N N 39.2 39.4 37.9 38.4 42.5 38.6 39.4 38.3 39.3 6.03 6.25 5.89 6.44 6.53 6.29 5.90 5.90 6.22 5.68 4.90 7.30 10.6 9.09 10.5 7.49 6.22 15.8 ------------------ ------------------ ------------------ ------------------ ------------------ ------------------ ------------------ ------------------ ------------------ ------------------ ------------------ ------------------ < 5.9 < 6.8 < 4.6 < 3.2 < 3.7 < 3.2 < 4.5 < 5.3 < 2.1 < 5.9 < 6.8 < 4.6 < 3.2 < 3.7 < 3.2 < 4.5 < 5.3 < 2.1 < 5.9 < 6.8 < 4.6 < 3.2 < 3.7 < 3.2 < 4.5 < 5.3 < 2.1 < 5.9 < 6.8 < 4.6 < 3.2 < 3.7 < 3.2 < 4.5 < 5.3 < 2.1 < 5.9 < 6.8 < 4.6 < 3.2 < 3.7 < 3.2 < 4.5 < 5.3 < 2.1 ------------------ < 5.9 < 6.8 < 4.6 < 3.2 < 3.7 < 3.2 < 4.5 < 5.4 < 2.2 ------------------ ------------------ ------------------ ------------------ ------------------ < 5.9 < 6.8 < 4.6 < 3.2 < 3.7 < 3.2 < 4.5 < 5.4 < 2.2 ND ND ND ND ND ND ND ND ND 5.8 6.7 4.5 3.2 3.6 3.2 4.4 5.3 2.1 ------------------ < 5.9 < 6.8 < 4.6 < 3.2 < 3.7 < 3.2 < 4.5 < 5.3 < 2.1 < 5.9 < 6.8 < 4.6 < 3.2 < 3.7 < 3.2 < 4.5 < 5.3 < 2.1 Table A-1 West Area Soil Quality Data Joslyn Manufacturing Supply Co. Brooklyn Center, Minnesota Page 14 of 15 10/26/2017 P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2017\Appendices\Appendix A\Table A-1 West Area_10032017.xlsx Parameter Analysis Location Units Depth Location Sample Type Date Acenaphthene Lab mg/kg Acenaphthylene Lab mg/kg Anthracene Lab mg/kg B(a)P Equivalent, 1999 PEFs Lab mg/kg Benzo(e)pyrene Lab mg/kg Benzo(g,h,i)perylene Lab mg/kg Carbazole Lab mg/kg Fluoranthene Lab mg/kg Fluorene Lab mg/kg Naphthalene Lab mg/kg Pentachlorophenol Lab mg/kg Perylene Lab mg/kg Phenanthrene Lab mg/kg Pyrene Lab mg/kg Chlorinated Dioxins / Furans 2,3,7,8-Dioxin, tetra Lab ng/kg 1,2,3,7,8-Dioxin, penta Lab ng/kg 1,2,3,4,7,8-Dioxin, hexa Lab ng/kg 1,2,3,6,7,8-Dioxin, hexa Lab ng/kg 1,2,3,7,8,9-Dioxin, hexa Lab ng/kg 1,2,3,4,6,7,8-Dioxin, hepta Lab ng/kg Dioxin, octa Lab ng/kg 2,3,7,8-Dibenzofuran, tetra Lab ng/kg 1,2,3,7,8-Dibenzofuran, penta Lab ng/kg 2,3,4,7,8-Dibenzofuran, penta Lab ng/kg 1,2,3,4,7,8-Dibenzofuran, hexa Lab ng/kg 1,2,3,6,7,8-Dibenzofuran, hexa Lab ng/kg 2,3,4,6,7,8-Dibenzofuran, hexa Lab ng/kg 1,2,3,7,8,9-Dibenzofuran, hexa Lab ng/kg 1,2,3,4,6,7,8-Dibenzofuran, hepta Lab ng/kg 1,2,3,4,7,8,9-Dibenzofuran, hepta Lab ng/kg Dibenzofuran, octa Lab ng/kg TEQ DF WHO05 , non-detects at zero for the detection limit Calc ng/kg TEQ DF WHO05, non-detects at half of the detection limit Calc ng/kg Dioxin TEQ (by method 4425)Lab ng/kg TCDD Equivalent, reporting limit at 0, TEF 2005 (EMPC @ 1)Calc ng/kg TCDD Equivalent, reporting limit at 0, TEF 2005 (EMPC @ 1/2)Calc ng/kg TCDD Equivalent, reporting limit at 1, TEF 2005 (EMPC @ 1)Calc ng/kg TCDD Equivalent, reporting limit at 1, TEF 2005 (EMPC @ 1/2)Calc ng/kg TCDD Equivalent, reporting limit at 1/2, TEF 2005 (EMPC @ 1)Calc ng/kg TCDD Equivalent, reporting limit at 1/2, TEF 2005 (EMPC@1/2)Calc ng/kg I-1 I-2 0-0.5'I-2 0.5-1.5'I-2 1.5-2.5'I-2 2.5-4'I-3 J-1 J-2 J-3 1/20/2003 1/20/2003 1/20/2003 1/20/2003 1/20/2003 1/20/2003 1/20/2003 1/20/2003 1/20/2003 N N N N N N N N N < 5.9 < 6.8 < 4.6 < 3.2 < 3.7 < 3.2 < 4.5 < 5.3 < 2.1 < 5.9 < 6.8 < 4.6 < 3.2 < 3.7 < 3.2 < 4.5 < 5.3 < 2.1 < 5.9 < 6.8 < 4.6 < 3.2 < 3.7 < 3.2 < 4.5 < 5.3 < 2.1 ------------------ ------------------ < 5.9 < 6.8 < 4.6 < 3.2 < 3.7 < 3.2 < 4.5 < 5.4 < 2.2 ------------------ < 5.9 < 6.8 < 4.6 < 3.2 < 3.7 < 3.2 < 4.5 < 5.3 < 2.1 < 5.9 < 6.8 < 4.6 < 3.2 < 3.7 < 3.2 < 4.5 < 5.3 < 2.1 < 5.9 < 6.8 < 4.6 < 3.2 < 3.7 < 3.2 < 4.5 < 5.3 < 2.1 < 36 < 41 < 28 < 19 < 23 < 20 < 27 < 33 < 13 ------------------ < 5.9 < 6.8 < 4.6 < 3.2 < 3.7 < 3.2 < 4.5 < 5.3 < 2.1 < 5.9 < 6.8 < 4.6 < 3.2 < 3.7 < 3.2 < 4.5 < 5.3 < 2.1 < 1.0 ------------1.013 jEMPC -- < 2.5 ------------4.348 j -- 44.231 j ------------10.716 j -- 184.018 j ------------45.538 -- 62.073 jEMPC ------------27.005 -- 7180.028 eb ------------1272.648 -- 37177.779 b ------------7284.551 eb -- < 1.0 ------------5.352 jc -- < 2.5 ------------6.576 j -- < 2.5 ------------6.918 jEMPC -- 106.487 jb ------------39.183 -- 31.46 j ------------11.419 j -- 42.957 jEMPC ------------18.091 -- 11.995 j ------------8.059 j -- 1490.469 ------------358.658 -- 67.155 j ------------27.197 EMPC -- 6414.033 b ------------976.888 -- ------------------ ------------------ 1921 <44 689 145 181 35 17 252 123 ------------------ ------------------ ------------------ ------------------ ------------------ ------------------ Page 15 of 15 10/26/2017 P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2017\Appendices\Appendix A\Table A-1 West Area_10032017.xlsx --Not analyzed/Not available. N Sample Type: Normal FD Sample Type: Field Duplicate a Estimated value, calculated using some or all values that are estimates. b Potential false positive value based on blank data validation procedures. c Coeluting compound. e Estimated value, exceeded the instrument calibration range. h EPA recommended sample preservation, extraction or analysis holding time was exceeded. j Reported value is less than the stated laboratory quantitation limit and is considered an estimated value. p Relative percent difference is >40% (25% CLP pesticides) between primary and confirmation GC columns. pp Small peak in chromatogram below method detection limit. EMPC Estimated maximum possible concentration. DI Value represents a criteria for 2,3,7,8-TCDD or 2,3,7,8-TCDD equivalents. Barr Standard Footnotes and Qualifiers (Historical) Minnesota Soil Reference Values Table A-2 Historic Soil Quality Data - Southern Lots and Roadway Joslyn Manufacturing and Supply Company Brooklyn Center, Minnesota 1 of 2 10/26/2017 P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2017\Appendices\Appendix A\Table A-2 Southern Lots and Roadway.xlsx RES1-SI1 RES1-SI2 RES2-SI1 RES2-SI3 RES2-SI4 SA1-Comp SA2-Comp SA3-COMP SA4-COMP SA5-Comp SA6-Comp SA7-Comp T1-Comp T2-Comp T3-Comp T4-1 3/04/2005 3/04/2005 3/04/2005 3/04/2005 3/04/2005 9/02/2004 9/02/2004 9/02/2004 9/02/2004 9/02/2004 9/02/2004 9/02/2004 07/29/2009 07/29/2009 07/29/2009 07/29/2009 0 - 0.5 ft 0 - 0.5 ft 0.5 - 1.5 ft 1.5 -4 ft 0-4 ft 0-4 ft 0-4 ft 0-4 ft N N N FD N N N N N N N N N N N N N N Parameter Analysis Location Units General Parameters Carbon, total organic Lab %----------------------------19.3 7.15 5.75 28.8 Solids, total Lab %--------------82.5 80.6 75.2 h 68.1 h -------------- Herbicides Pentachlorophenol Lab mg/kg --------------< 0.0061 < 0.0062 < 0.0067 h < 0.0073 h -------------- Chlorinated Dioxins / Furans 2,3,7,8-Dioxin, tetra Lab ng/kg < 1.0 < 1.0 2.725 EMPC < 1.0 < 1.0 < 1.0 < 0.992 < 1.0 < 1.0 < 0.019 h < 0.057 h < 1.0 < 1.0 0.165 jEMPC 2.26 0.913 j 0.610 jEMPC < 0.167 1,2,3,7,8-Dioxin, penta Lab ng/kg 0.642 j 1.956 j 4.333 5.957 < 2.5 < 2.5 < 2.481 < 2.5 < 2.5 0.280 jh < 0.035 h 0.214 j 0.179 jEMPC 0.317 j 10.8 8.07 4.47 3.57 j 1,2,3,4,7,8-Dioxin, hexa Lab ng/kg 1.944 j 7.1940 77.327 102.864 0.232 j 0.285 j < 2.481 < 2.5 < 2.5 0.471 jhEMPC 0.078 jh 0.455 j 0.313 jEMPC 0.347 jEMPC 34.7 26.7 12.6 5.78 1,2,3,6,7,8-Dioxin, hexa Lab ng/kg 7.813 62.854 390.921 719.823 0.660 j 0.911 j 2.830 j < 2.5 < 2.5 1.277 jh 0.306 jh 1.255 j 0.948 j 1.206 j 794 e 471 108 169 1,2,3,7,8,9-Dioxin, hexa Lab ng/kg 5.529 25.329 58.555 122.937 0.490 j 0.708 j < 2.481 < 2.5 < 2.5 1.134 jh 0.224 jhEMPC 1.128 j 1.003 j 1.227 j 123 83.6 35.1 25.4 1,2,3,4,6,7,8-Dioxin, hepta Lab ng/kg 248.611 2656.809 16540.965 36059.420 21.136 29.226 145.291 132.713 46.878 39.439 bh 7.937 bh 35.232 27.327 29.941 32900 17300 5360 10100 Dioxin, octa Lab ng/kg 1843.382 eb 19942.814 eb 271822.016 eb 570865.629 eb 145.517 b 193.481 b 1002.516 eb 1073.116 e 341.913 280.959 bh 49.565 bh 294.493 244.150 228.059 234000 e 132000 44700 97400 2,3,7,8-Dibenzofuran, tetra Lab ng/kg < 1.0 7.499 c 6.097 c 6.274 c < 1.0 < 1.0 < 0.992 < 1.0 < 1.0 0.425 ch < 0.058 h < 0.443 < 0.350 < 0.464 1.49 EMPC 4.26 0.772 j < 0.558 1,2,3,7,8-Dibenzofuran, penta Lab ng/kg < 2.5 0.969 j 33.480 37.517 < 2.5 < 2.5 < 2.481 < 2.5 < 2.5 0.149 jh < 0.047 h 0.158 j < 2.5 < 2.5 5.34 P 11.8 P 2.12 jEMPC 1.67 j EMPCP 2,3,4,7,8-Dibenzofuran, penta Lab ng/kg < 2.5 1.930 j 27.610 31.845 < 2.5 < 2.5 < 2.481 < 2.5 < 2.5 0.276 jh < 0.044 h 0.284 j 0.342 j 0.420 j 6.18 10.6 1.52 j 0.471 j 1,2,3,4,7,8-Dibenzofuran, hexa Lab ng/kg 2.945 jEMPC 11.841 246.71 300.766 0.464 j 0.458 j 0.572 jEMPC < 2.5 < 2.5 0.998 jbh 0.218 jbh 0.635 jEMPC 0.563 jEMPC 0.605 j 170 154 P 22.5 28 1,2,3,6,7,8-Dibenzofuran, hexa Lab ng/kg 0.923 jEMPC 3.356 47.883 60.483 < 2.5 < 2.5 < 2.481 < 2.5 < 2.5 0.430 jh 0.120 jh 0.521 j 0.395 jEMPC 0.654 j 27.7 36.5 5.82 4.64 j 1,2,3,7,8,9-Dibenzofuran, hexa Lab ng/kg < 2.5 < 2.5 < 2.5 15.142 < 2.5 < 2.5 < 2.481 < 2.5 < 2.5 < 0.120 h < 0.022 h < 2.5 < 2.5 < 2.5 4.38 P 10.2 P 2.15 j < 1.37 2,3,4,6,7,8-Dibenzofuran, hexa Lab ng/kg 2.278 j 2.871 64.604 48.965 < 2.5 < 2.5 < 2.481 < 2.5 < 2.5 0.490 jh 0.191 jh 1.093 j 1.000 j 1.611 j 70 66.3 P 14.1 13.7 1,2,3,4,6,7,8-Dibenzofuran, hepta Lab ng/kg 73.351 441.851 4050.639 6750.237 4.831 6.755 37.458 23.134 8.163 10.748 bh 1.736 jbh 14.027 9.191 10.379 7540 4310 1120 1880 1,2,3,4,7,8,9-Dibenzofuran, hepta Lab ng/kg 5.477 37.704 311.2 524.085 0.469 j 0.486 jEMPC < 2.481 < 2.5 < 2.5 0.958 jh 0.159 jh 0.677 j 0.581 j 0.512 j 529 331 71.2 119 Dibenzofuran, octa Lab ng/kg 360.604 2142.915 20242.349 e 42579.379 15.455 22.554 250.824 98.848 32.620 35.586 h 5.404 h 49.653 31.620 41.648 63000 32400 7640 15400 TCDD Equivalent, reporting limit at 0, TEF 2005 Calc ng/kg 6.53 a 52.6 a 401 a 772 a 0.497 a 0.663 a 2.52 a 1.91 a 0.663 1.43 a 0.196 a 1.38 a 1.00 a 1.56 a 639 367 107 183 TCDD Equivalent, reporting limit at 1/2, TEF 2005 Calc ng/kg 7.61 a 53.3 a 401 a 772 a 3.08 a 3.25 a 5.34 a 5.01 a 3.76 2.07 a 2.53 a 2.03 a 1.68 a 1.75 a 639 367 107 183 Sample Type Location Date RES1-SI3 3/04/2005 Depth Page 2 of 2 10/26/2017 P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2017\Appendices\Appendix A\Table A-2 Southern Lots and Roadway.xlsx --Not analyzed/Not available. N Sample Type: Normal FD Sample Type: Field Duplicate a Estimated value, calculated using some or all values that are estimates. b Potential false positive value based on blank data validation procedures. c Coeluting compound. e Estimated value, exceeded the instrument calibration range. h EPA recommended sample preservation, extraction or analysis holding time was exceeded. j Reported value is less than the stated laboratory quantitation limit and is considered an estimated value. p Relative percent difference is >40% (25% CLP pesticides) between primary and confirmation GC columns. EMPC Estimated maximum possible concentration. DI Value represents a criteria for 2,3,7,8-TCDD or 2,3,7,8-TCDD equivalents. Footnotes and Qualifiers Minnesota Soil Reference Values 10/26/2017 4:24 PM P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2017\Appendices\Appendix B\Appendix B - Opinion of Remedial Cost.xlsx Table B-1 Alternative 8B - Limited Onsite Consolidation with Soil Cover at West Area (Onsite Floodplain Mitigation) Brooklyn Center, Minnesota Item Quantity Unit Unit Cost Total Cost Capital Costs Mobilization (general conditions & safety plan)1 LS 125,465$ 125,465$ Temporary Erosion and Sediment Control Construction entrance into West Area 1 EA 1,800$ 1,800$ Establish silt fence 3,110 LF 3$ 9,330$ Other erosion control items for NPDES requirements 1 LS 2,500$ 2,500$ Site Preparation Remove existing fence 2,562 LF 3$ 7,686$ Dewatering (pump to onsite system)1 LS 25,000$ 25,000$ Remove misc demolition debris present on surface 1 LS 1,000$ 1,000$ Clearing and grubbing, chip and spread onsite- West Area 4.33 AC 10,000$ 43,300$ Clearing and grubbing, chip and spread onsite- Southern Lots 0.19 AC 10,000$ 1,900$ Access road aggregate (1,500' x 15' x 1' avg)833 CY 20$ 16,667$ Decontamination pad/liner/drainage for south end 1 LS 15,000$ 15,000$ Decon water management 1 LS 20,000$ 20,000$ Contaminated Soil Excavation and Consolidation Consolidation Required Excavate 3.5', and consolidate WA-2C 273 CY 8$ 2,185$ Excavate 1.0', and consolidate WA-2D 134 CY 8$ 1,070$ Excavate 3.5', and consolidate WA-3A 626 CY 8$ 5,006$ Excavate 1.0', and consolidate WA-3B 444 CY 8$ 3,548$ Excavate 3.5', and consolidate WA-4A 987 CY 8$ 7,895$ Excavate 2.0', and consolidate WA-4B 933 CY 8$ 7,463$ Excavate 3.5', and consolidate WA-6MID 2,791 CY 8$ 22,328$ Excavate 3.5', and consolidate WA-6N 1,353 CY 8$ 10,821$ Excavate 3.5', and consolidate WA-6S 2,939 CY 8$ 23,516$ Subtotal Excavation Volume 10,479 CY Transport and Disposal to Subtitle D Landfill Excavate 2.5' and consolidate WA-1A 6,061 TON 25$ 151,521$ Excavate 2.0' and consolidate WA-1B 2,134 TON 25$ 53,340$ Excavate 2.5', stage, load, and transport WA-2A 1,876 TON 25$ 46,890$ Excavate 2.0', stage, load, and transport WA-2B 716 TON 25$ 17,907$ Excavate 2.5', stage, load, and transport WA-5 (former ice chute)681 TON 25$ 17,024$ Excavate 2.5', stage, load, and transport WA-7 13,735 TON 25$ 343,373$ Excavate 2.5', stage, load, and transport WA-8 (former rail spur)387 TON 25$ 9,683$ Excavate 4.0', stage, load, and transport Southern Lots 1,742 TON 25$ 43,556$ Total Excavation Weight 27,332 TON Total Excavation Volume 19,523 CY Construction of Onsite Repository Geotextile (16 oz Nonwoven needle-punched)6,837 SY 3$ 20,510$ Import / grade 1.5 ft engineered cover soil 3,160 CY -$ -$ Import / grade 0.5' topsoil 1,139 CY -$ -$ Upland planting/seeding 1.41 ACRE 3,000$ 4,238$ Operable Unit 5 Joslyn Manufacturing & Supply Co. Site 10/26/2017 4:24 PM P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2017\Appendices\Appendix B\Appendix B - Opinion of Remedial Cost.xlsx Table B-1 Alternative 8B - Limited Onsite Consolidation with Soil Cover at West Area (Onsite Floodplain Mitigation) Brooklyn Center, Minnesota Item Quantity Unit Unit Cost Total Cost Operable Unit 5 Joslyn Manufacturing & Supply Co. Site OU5 Site Restoration WA-1A Geotextile (16 oz Nonwoven needle-punched)5,195 SY 3$ 15,585$ Import backfill - 1.5 ft 2,598 CY -$ -$ Import 1.0' wetland-like soil 1,732 CY 30$ 51,950$ Wetland planting/seeding 1.07 AC 10,000$ 10,733$ WA-1B Import backfill - 1.5 ft 1,143 CY -$ -$ Import 0.5' topsoil 381 CY -$ -$ Upland planting/seeding 0.47 AC 3,000$ 1,417$ WA-2A Geotextile (16 oz Nonwoven needle-punched)1,608 SY 3$ 4,823$ Import backfill - 1.5 ft 804 CY -$ -$ Import 1.0' wetland-like soil 536 CY 30$ 16,077$ Wetland planting/seeding 0.33 AC 10,000$ 3,322$ WA-2B Import backfill - 1.5 ft 384 CY -$ -$ Import 0.5' topsoil 128 CY -$ -$ Upland planting/seeding 0.16 AC 3,000$ 476$ WA-2C Geotextile (16 oz Nonwoven needle-punched)234 SY 3$ 702$ Import backfill - 2.5 ft 195 CY -$ -$ Import 1.0' wetland-like soil 78 CY 30$ 2,341$ Wetland planting/seeding 0.05 AC 10,000$ 484$ WA-2D Import backfill - 2.5 ft 334 CY -$ -$ Import 0.5' topsoil 67 CY -$ -$ Upland planting/seeding 0.08 AC 3,000$ 249$ WA-3A Geotextile (16 oz Nonwoven needle-punched)328 SY 3$ 985$ Import backfill - 2.5 ft 274 CY -$ -$ Import 1.0' wetland-like soil 109 CY 30$ 3,284$ Wetland planting/seeding 0.07 AC 10,000$ 679$ WA-3B Import backfill - 2.5 ft 205 CY -$ -$ Import 0.5' topsoil 41 CY -$ -$ Upland planting/seeding 0.05 AC 3,000$ 153$ WA-4A Geotextile (16 oz Nonwoven needle-punched)838 SY 3$ 2,513$ Import backfill - 2.5 ft 698 CY -$ -$ Import 1.0' wetland-like soil 279 CY 30$ 8,377$ Wetland planting/seeding 0.17 AC 10,000$ 1,731$ WA-4B Import backfill - 1.5 ft 700 CY -$ -$ Import 0.5' topsoil 233 CY -$ -$ Upland planting/seeding 0.29 AC 3,000$ 867$ 10/26/2017 4:24 PM P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2017\Appendices\Appendix B\Appendix B - Opinion of Remedial Cost.xlsx Table B-1 Alternative 8B - Limited Onsite Consolidation with Soil Cover at West Area (Onsite Floodplain Mitigation) Brooklyn Center, Minnesota Item Quantity Unit Unit Cost Total Cost Operable Unit 5 Joslyn Manufacturing & Supply Co. Site WA-5 (former ice chute) Geotextile (16 oz Nonwoven needle-punched)584 SY 3$ 1,751$ Import backfill - 2.0 ft 389 CY -$ -$ Import 0.5' topsoil 97 CY -$ -$ Upland planting/seeding 0.12 AC 3,000$ 362$ WA-6MID Geotextile (16 oz Nonwoven needle-punched)2,392 SY 3.00$ 7,177$ Import backfill - 2.5 ft 1,994 CY -$ -$ Import 1.0' wetland-like soil 797 CY 30.00$ 23,923$ Wetland planting/seeding 0.49 AC 10,000.00$ 4,943$ WA-6N Geotextile (16 oz Nonwoven needle-punched)1,159 SY 3.00$ 3,478$ Import backfill - 2.5 ft 966 CY -$ -$ Import 1.0' wetland-like soil 386 CY 30.00$ 11,594$ Wetland planting/seeding 0.24 AC 10,000.00$ 2,396$ WA-6S Geotextile (16 oz Nonwoven needle-punched)2,046 SY 3.00$ 6,138$ Import backfill - 2.5 ft 1,705 CY -$ -$ Import 1.0' wetland-like soil 682 CY 30.00$ 20,461$ Wetland planting/seeding 0.42 AC 10,000.00$ 4,228$ WA-7 Geotextile (16 oz Nonwoven needle-punched)11,773 SY 3.00$ 35,318$ Import backfill - 1.5 ft 5,886 CY -$ -$ Import 1.0' wetland-like soil 3,924 CY 30.00$ 117,728$ Wetland planting/seeding 2.43 AC 10,000.00$ 24,324$ WA-8 (former rail spur) Geotextile (16 oz Nonwoven needle-punched)332 SY 3.00$ 996$ Import backfill - 2.0 ft 221 CY -$ -$ Import 0.5' topsoil 55 CY -$ -$ Upland planting/seeding 0.07 AC 3,000.00$ 206$ Cover/Backfill Required Summary Cover for Repository (3,160) CY Backfill Required for OU5 (18,496) CY Total Cover/Backfill Required (21,656) CY Cover/Backfill Source Summary Onsite Mitigation Area Soil for use on OU5 7,200 CY Total Cover/Backfill Required (21,656) CY Backfill Imported (14,456) CY Topsoil Required Summary Topsoil for Repository (1,139) CY Topsoil for OU5 (1,003) CY Total Topsoil Required (2,142) CY Topsoil Source Summary Total Topsoil Required (2,142) CY Topsoil Imported (2,142) CY Wetland-Like Soils Source Summary Wetland-Like Soils Required (8,525) CY Wetland-Like Soils Imported (8,525) CY 10/26/2017 4:24 PM P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2017\Appendices\Appendix B\Appendix B - Opinion of Remedial Cost.xlsx Table B-1 Alternative 8B - Limited Onsite Consolidation with Soil Cover at West Area (Onsite Floodplain Mitigation) Brooklyn Center, Minnesota Item Quantity Unit Unit Cost Total Cost Operable Unit 5 Joslyn Manufacturing & Supply Co. Site Imported Soil Costs Onsite Mitigation Area Soil for use on OU5 7,200 CY 8$ 57,600$ Import Backfill 14,456 CY 20$ 289,114$ Import Topsoil 2,142 CY 15$ 32,132$ Soil Quality Testing for Imported Backfill 1 LS 21,600$ 21,600$ Soil Quality Testing for Imported and OnsiteTopsoil 1 LS 4,320$ 4,320$ Soil Quality Testing for Imported Wetland-Like Soil 1 LS 12,960$ 12,960$ OU5 Stormwater Management Plan (see Table B-2 for details)1 LS 440,000$ 440,000$ Potential Mitigation Area Costs (see Table B-3 for details)1 LS 270,000$ 270,000$ Final Improvements Remove decon pad 1 LS 2,500$ 2,500$ Reestablish fence around entire West Area 2,562 FT 20$ 51,240$ Purchases for Floodplain and Wetland Mitigation Permanent Wetland 1S Impacts (2.5:1 replacement) minus credit 1.36 ACRE 63,650$ 86,564$ Direct Subtotal 2,721,322$ Engineering (Design, Permitting, & Admin)1 LS 196,685$ 196,685$ Construction (Mgmt, Oversight, Survey, & Reporting)1 LS 282,900$ 282,900$ Direct and Indirect Subtotal 3,200,907$ Contingency 30%1 LS 960,272$ 960,272$ Capital Total 4,160,000$ Operation and Maintenance Perimeter fence replacement ($40,000/10 years)1 LS 4,000$ 4,000$ Annual routine site maintenance (signs, tree cleanup, etc)1 LS 4,500$ 4,500$ Annual wetland vegetation monitoring and maintenance 1 LS 2,500$ 2,500$ Quarterly Site Inspection and Annual Report 1 LS 5,000$ 5,000$ Direct Subtotal 16,000$ O&M Contingency 30%1 LS 4,800$ 4,800$ Annual Operation and Maintenance Total 20,800$ 30-year O&M Total - No discount rate applied 624,000$ TOTAL CAPITAL & O&M 4,780,000$ 10/26/2017 4:24 PM P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2017\Appendices\Appendix B\Appendix B - Opinion of Remedial Cost.xlsx Table B-2 OU 5 Stormwater Management Plan- Alternative 8B Brooklyn Center, Minnesota Item Quantity Unit Unit Cost Total Cost Temporary Stormwater Management South Swale Import fill and create swale diversion 30 CY 20$ 600$ Stormwater Diversion Sheet Pile 935' to direct flow around WA-7 14,025 SF 25$ 350,625$ Pump Building 1B Manhole 1 LS 26,000$ 26,000$ Permanent Stormwater Management WA-5 (Former Ice Chute) Build up area of former ice chute to prevent direct connection to lake 292 CY 20$ 5,838$ WA-8 (Former Rail Spur) Build up area of railroad spur to recreate DNR jurisdictional boundary 43 CY 20$ 860$ Building 1B Pond (Roof Drainage) Remove, decon and dispose/recycle existing 24" RCP 92 LF 30$ 2,760$ Remove, decon and dispose/recycle existing 24" RC Flared End Section 1 EA 100$ 100$ 24" RCP, CL. III 92 LF 40$ 3,680$ 24" RC Flared End Section 1 EA 600$ 600$ Pipe to West 24" RCP, CL. III 255 LF 40$ 10,200$ 24" RC Flared End Section 1 EA 1,200$ 1,200$ 24" Tideflex TF-1 Check Valve 1 EA 5,000$ 5,000$ Riprap and Granular Filter 10 CY 50$ 500$ Site Restoration Remove swale diversion 1 LS 200$ 200$ Remove (or drive deeper) sheet piling around WA-7 14,025 SF 2$ 28,050$ Pipe to Lake Import 0.5' topsoil 30 CY 15$ 444$ Upland planting/seeding 0.04 ACRE 3,000$ 110$ Building 1B Pond Import 0.5' topsoil 17 CY 15$ 256$ Upland planting/seeding 0.02 ACRE 3,000$ 63$ Imported Backfill Soil Summary South Swale (30) WA-5 (Former Ice Chute)(292) WA-8 (Former Rail Spur)(43) TOTAL (365) Imported Topsoil Summary Pipe to Lake (30) Building 1B Pond (17) TOTAL (47) Soil Testing Soil Quality Testing for Imported Backfill 1 LS 1,440$ 1,440$ Soil Quality Testing for Imported Topsoil 1 LS 1,440$ 1,440$ TOTAL 440,000$ Operable Unit 5 Joslyn Manufacturing & Supply Co. Site 10/26/2017 4:24 PM P:\Mpls\23 MN\27\2327110\WorkFiles\West Area\ROD\ROD Update 2017\Appendices\Appendix B\Appendix B - Opinion of Remedial Cost.xlsx Table B-3 Onsite Mitigation Area Preparation and Restoration- Alternative 8B Brooklyn Center, Minnesota Item Quantity Unit Unit Cost Total Cost Temporary Erosion and Sediment Control Miscellaneous erosion control items for NPDES requirements 1 LS 2,500$ 2,500$ Site Preparation Dewatering 1 LS 6,000$ 6,000$ Clearing and grubbing, chip and spread onsite 1.2 ACRE 5,000$ 6,200$ Site Restoration Excavate/regrade mitigation area 7,200 CY 8$ 57,600$ Reuse soil onsite for clean cover/backfill 7,200 CY -$ -$ Import 0.5' topsoil 1,000 CY 15$ 15,000$ Upland planting/seeding 1.2 ACRE 3,000$ -$ Plant trees 1 LS 25,000$ 25,000$ Direct Subtotal 112,300$ Engineering (Design, Permitting, & Admin)1 LS 11,230$ 11,230$ Construction (Mgmt, Oversight, Survey, & Reporting)1 LS 22,460$ 22,460$ Direct and Indirect Subtotal 145,990$ Contingency 30%1 LS 43,797$ 43,797$ Capital Total 190,000$ Operation and Maintenance Annual routine maintenance and repairs (tree cleanup, etc)1 LS 4,500$ 4,500.00$ Annual wetland vegetation monitoring and maintenance 1 LS 2,500$ 2,500.00$ Wetland Site Inspection and Annual Report 1 LS 5,000$ 5,000.00$ Direct Subtotal 12,000.00$ O&M Contingency 30%1 LS 3,600$ 3,600.00$ Annual Operation and Maintenance Total 15,600.00$ 5-year O&M Total - No discount rate applied 78,000.00$ TOTAL 270,000$ Focused Feasibility Study - Operable Unit 5 Joslyn Manufacturing & Supply Co. Site www.pca.state.mn.us Minnesota Pollution Control Agency 651-296-6300 | 800-657-3864 or use your preferred relay service | Info.pca@state.mn.us August 2017 | g-27-03g Available in alternative formats Response to comments and questions: Joslyn Superfund Site This document is a response to public comments and questions submitted to the Minnesota Pollution Control Agency (MPCA) on the proposed cleanup plan for the Joslyn Superfund Site in Brooklyn Center. Comments and questions were grouped by topic and are paraphrased below, followed by a response from MPCA. The next steps in the cleanup process are discussed at the end of this document. The MPCA appreciates the thoughtful comments and questions that were submitted, and hopes that this document provides a greater understanding of the cleanup plan at the Joslyn Superfund Site. Comment 1: The cleanup would not result in an environmental benefit, or might make things worse. • What is the risk of exposure right now? • Will this proposed cleanup plan do more harm than good? • Will the wildlife and environment benefit from the cleanup? The main chemicals of concern at this site are dioxins, which are present at high concentrations within the soil. Dioxins are extremely toxic and are a serious public health threat if there is a risk of exposure. In this case, the main risk is through ingesting or touching contaminated soil. Dioxins are bio-accumulative and extremely persistent in the environment; we all have some level of dioxins in our bodies from other sources, such as animal fats in meat and dairy products. A fence was put in place at the site to limit the risk of exposure to dioxins in the short-term. However, the fence is not an adequate long-term solution, as human trespassers and wildlife may be exposed to the dioxins. Though it may not be immediately obvious, wildlife that walk over the ground or burrow into the contaminated ground may be exposed to dioxins and the chemicals may accumulate in their bodies. Dioxins can impact the food chain as larger animals may consume smaller animals that have been exposed to dioxins. The goal of this cleanup is to protect human health and the environment by eliminating pathways for exposure to dioxins. The cleanup will restore the environment to one that is supportive of current and future wildlife. The site will remain as green space and will be better able to support wildlife in the long-term. Though a fence will be installed around most of the site, it is not necessary from an environmental perspective. After the cleanup activities, the site will be fully restored with all native trees, shrubs and wetland grasses. Comment 2: An environmental impact statement is needed. • Will an environmental impact statement be conducted? • Is an environmental impact statement required? An Environmental Impact Statement (EIS) is designed to publicly identify negative environmental effects of a proposed project, and to identify ways to avoid or minimize them before the project is conducted. Specifically, an environmental impact statement (EIS) is required when a project meets or exceeds certain thresholds specified under Minnesota law. This cleanup does not hit any of the thresholds that would trigger an EIS. For this reason, and because the proposed cleanup plan has already been evaluated through the Superfund process as described below, an EIS is not planned. Page 2 of 3 August 2017 | g-27-03g This cleanup plan was developed under Superfund criteria (as prescribed by federal law). The Superfund process covers many of the same elements that would be reviewed in an EIS, such as presenting project information to the public, assessing potential water impacts, and preparing a restoration plan. Thus, completing an EIS would duplicate work that was already done under the Superfund process, and would further delay cleanup of the site. Comment 3: The residential streets are not suitable for heavy construction traffic. • What route will the construction vehicles travel? MPCA agrees that construction vehicles should not use the residential streets of Twin Lake Avenue or Lakeview Avenue North for travel routes for construction equipment. Joslyn is attempting to negotiate access to an adjacent commercial property, allowing the heavy construction traffic to remain on industrial property with suitable roadways. Discussions are taking place at this time. Comment 4: Middle Twin Lake could be impacted during cleanup activities. The wetlands need to be properly protected and restored. • Will the proposed plan ensure that Middle Twin Lake is sufficiently protected, and that the wetlands are sufficiently restored? • Are the wetlands protected? The MPCA, just like the surrounding community, is concerned about protecting Middle Twin Lake and the wetlands at the site. Understandably, concerns have been voiced about excavating soils on the edge of Middle Twin Lake. The cleanup plan calls for most of the excavation activities to be at least 15 feet from the edge of Middle Twin Lake. Silt fencing will be placed around most of the perimeter of the site, and sheet piling will be installed to a depth of approximately 10 feet in select areas of the site as a perimeter control to prevent any stormwater runoff from the soil to Middle Twin Lake. Some comments and questions were submitted regarding specific plants and seed mixes (such as plant mix 34-271 and 34-241) for restoration of the wetland. Joslyn has included seed mixes in their wetland restoration plan that are very similar to those recommended (34-181, 34-261, 36-211, 35-221 in various areas at the site, and include Big Blue Stem, a species cited in one comment). The seed mixes were chosen specifically for the areas they will be placed in, and include only native plants. The wetland will be completely restored after the completion of the excavation activities. An additional question concerned maintenance of the mounded area. The mounded area containing some of the contaminated soil will be capped with fabric and approximately 2 feet of clean soil. The mound will be seeded with grasses and will be mowed regularly to prevent any large bushes or trees from growing on the mound and creating the potential to expose contaminated soils. The remainder of the site will be restored to native wetland, and there will be no overall loss of floodplain. Joslyn is completing all the required permitting to conduct this cleanup project at the site through the City of Brooklyn Park, Shingle Creek Watershed Commission, Minnesota Department of Natural Resources, United States Army Corps of Engineers, and other agencies. The cleanup will not take place until all necessary permits are in place and approved. Page 3 of 3 August 2017 | g-27-03g Comment 5: More trees should be planted for screening and wildlife habitat. •Can more trees be planted? •Can mature trees be planted? MPCA and Joslyn agree that the trees play a significant role at the site regarding the habitat, wildlife, and visual screening from nearby properties and from Middle Twin Lake. Where possible, trees will be left in place. However, it is not possible to excavate the contaminated soil (which is necessary to protect human health and the environment) without removing most of the trees in the area. MPCA has discussed the community’s interest in planting mature trees with Joslyn. In response to the neighborhood’s strong concerns about this issue, Joslyn has more than doubled the number of trees and shrubs it will plant, to over 170. The trees will be 6 to 8 feet tall on average. The size and maturity of the selected trees is based on their ability to thrive, growth rate, and ability to adapt after transplant. Joslyn has also selected a mix of trees and shrubs that will provide a variety in appearance, size and shape, leaf type, and color where some trees and shrubs will be green year round. The planting plan is available here. Cleanup plan and next steps The MPCA appreciates the comments and questions that were submitted. MPCA understands that this cleanup will have a significant impact on appearance of the property and will cause a disruption during construction. Although there will be short-term disruption during construction and longer-term appearance changes to the property, it is important that this cleanup be conducted to resolve risks to human health and the environment, and it will move forward as proposed. The next steps in the Superfund process are to finalize the updated proposed plan, which will be included in the Record of Decision (ROD) document. Once the ROD is complete and access to the site is obtained from the adjacent commercial property, Joslyn can move forward with cleanup work under supervision of the MPCA. The anticipated timeline for construction will be posted on the MPCA Joslyn website when it becomes available. Exhibit B M E M O R A N D U M DATE: August 5, 2022 TO: Ginny McIntosh, City Planner/Zoning Administrator FROM: Mike Albers, P.E., City Engineer SUBJECT: Special Use Permit Application Review – Joslyn OU5 Remediation Project Public Works staff reviewed the following documents submitted for review for the Joslyn OU5 Remediation Project: Preliminary Plans that were contained in the July 11, 2022 Memorandum Subject to final staff approval, the referenced plans must be revised in accordance with the following comments/revisions and approved prior to issuance of a Special Use Permit. General Comments 1. Complete plans should be submitted for review including, existing conditions, access and staging, removals, site plan, grading, drainage, and erosion control plans. As a result, some of these comments may have already been addressed. a.Haul routes and the proposed method of erosion control on haul roads b. Temporary erosion control plans/details should be submitted. c.Details of the proposed permanent fence should be included in the plans. Type, height, foundations, etc. d.Revise the location of the permanent fence and landscape screening to be outside of the existing right-of-way at the north end of Twin Lake Avenue. The City will preserve the existing right-of-way at the north end of Twin Lake Avenue to potentially construct a better turnaround as part of a future street reconstruction project. 2. Haul routes should be clearly identified to allow for verification of structural capacity. The applicant shall maintain and restore streets to a condition equally as good as that in which they were found when hauling was started. 3.All streets that access this Project site shall be kept clean by means of a pickup sweeper. No accumulations of dirt shall be allowed. Street sweeping shall occur immediately behind tracking vehicles as directed by the City. Perform street sweeping of the Project site, haul route and adjacent streets on a daily basis, and at more frequent intervals if conditions warrant such action and as ordered by the City. 4. Hours of operation for all activities shall adhere to the following City requirements. a.No construction equipment shall be operated between 7:00 P.M. and 7:00 A.M. unless specifically authorized by the City. b. No work shall be done on Sundays unless special approval is granted by the City. c.No work shall be done on Official City Holidays unless special approval is granted by the City. 5.Restrictive covenants are mentioned to ensure the property isn’t developed. Provide a copy of the development covenants. Exhibit C Joslyn OU5 Remediation Project Special Use Permit Application Review Memo, August 5, 2022. 6. Provide access agreements for hauling across adjacent properties should be submitted to the City for review. 7. All requirements of the Shingle Creek Watershed Commission and the MPCA shall be adhered to. 8. Upon project completion the applicant must submit an as-built survey of the property, improvements and utility service lines and structures; and provide certified record drawings of all project plan sheets depicting any associated private and/or public improvements, revisions and adjustments. The as-built survey must also verify that all property corners have been established and are in place at the completion of the project as determined and directed by the City Engineer. 9. Inspection for the private site improvements must be performed by the applicant’s design/project engineer. Upon project completion, the design/project engineer must formally certify through a letter that the project was built in conformance with the approved plans and under the design/project engineer’s immediate and direct supervision. The engineer must be certified in the State of Minnesota and must certify all required as-built drawings (which are separate from the as-built survey). Prior to Issuance of a Land Alteration 10. Final construction/demolition plans and specifications need to be received and approved by the City Engineer in form and format as determined by the City. The final plan must comply with the approved preliminary plan and/or as amended, as required by the City Engineer. 11. During construction of the site improvements, and until the permanent turf and plantings are established, the applicant will be required to reimburse the City for the administration and engineering inspection efforts. Please submit a deposit of $2,500 that the City can draw upon on a monthly basis. 12. A construction management plan and agreement is required that addresses general construction activities and management provisions, traffic control provisions, emergency management provisions, storm water pollution prevention plan provisions, tree protection provisions, general public welfare and safet y provisions, definition of responsibilit y p rovisions, temporary parking provisions, overall site condition provisions and non-compliance provisions. A separate $2,500 deposit will be required as part of the non-compliance provision. Anticipated Permitting 13. A City Land Disturbance permit is required. 14. A Watershed plan review and approval is required. 15. Other permits not listed may be required and is the responsibility of the developer to obtain and warrant. 16. Copies of all required permits must be provided to the City prior to issuance of applicable building and land disturbance permits. 17. A preconstruction conference must be scheduled and held with City staff and other entities designated by the City. The aforementioned comments are provided based on the information submitted by the applicant at the time of this review. Other guarantees and site development conditions may be further prescribed throughout the project as warranted and determined b y the City.