D2 Project Environmental Remediation Briefing August 21, 2018

Transcription

1 D2 Project Environmental Remediation Briefing August 21, 2018 The Union Square Revitalization Project (USQ) is a 2.4 million square foot transit-oriented, mixed use project that is transforming Union Square, Somerville into Boston s next great urban employment hub. The redevelopment of the D2 Block, USQ Phase 1, will remediate approximately 4-acres of a contaminated, vacant urban infill site and create productive new office/lab and residential uses that contribute to community goals for the neighborhood, including new jobs, commercial taxes and affordable housing. The remediation will occur as part of the USQ Phase 1 Project and will be guided by a Licensed Site Professional (an environmental remediation expert) in accordance with state and federal regulations. The MEPA Phase 1 waiver will not change the scope or timing of the remediation. The USQ Phase 1 Project is planned on land partially created by the filling in of the Millers River in the late-1800s, and has since been used for a combination of commercial, residential and industrial purposes. Both the fill materials and historic industrial operations have contributed oil and hazardous materials to the soil over time. The USQ Phase 1 Project Site is contaminated with polychlorinated biphenyls (PCBs), metals, petroleum hydrocarbons, and polyaromatic hydrocarbons (PAHs) in the soil. Chlorinated volatile organic compounds (VOCs) have been detected in groundwater on a small northeast portion of the site. Due to contamination, the site cleanup will be regulated by both federal and state laws. Cleanup of the PCBs will be conducted under the federal Toxic Substance Control Act (TSCA) overseen by the United States Environmental Protection Agency (EPA). The other site contaminants, mostly associated with the historic fill common throughout the area, will be cleaned up under the Massachusetts Contingency Program (MCP), a state program overseen by a Licensed Site Professional (LSP). An LSP is an environmental engineer or scientist experienced in the cleanup of oil and hazardous material contamination. LSPs are licensed by the state Board of Registration of Hazardous Waste Site Cleanup Professionals based upon education, experience, and passing an examination on applicable regulations and relevant technical issues. They are required to maintain their licenses by taking numerous educational courses on the evolving regulations and related technical practice issues. The LSP's job is to develop and execute a scope of work that will satisfy the state requirements to address contaminated property (these requirements are set forth in Massachusetts General Law c. 21E and the MCP). To summarize contamination and cleanup activities, the USQ Phase1 Project Site has been divided in two parts: the Kiley Barrel Disposal Site and the Remainder of the D2 Block" as shown on Figure 1. Kiley Barrel Disposal Site The northernmost portion of the USQ Phase1 Project Site, the 31,000 square foot Kiley Barrel site, was home to a facility that cleaned, refurbished and distributed drums for nearly four decades which contaminated the property. Since 1990, a series of geotechnical and environmental studies have been conducted to understand the environmental contamination that effects the property. These studies found contaminants that include PCBs, metals, petroleum hydrocarbons and PAHs in the soil. Volatile organic compounds (VOCs), including chlorinated VOCs were detected in groundwater on a small northeast portion of the Kiley Barrel site. Studies were also conducted to evaluate if the indoor air on neighboring properties was affected by chlorinated VOCs that may be associated with the Kiley Barrel Site. An evaluation of the indoor air quality performed in accordance with the MCP concluded that the levels of contaminants pose a level of No Significant Risk (NSR).

2 In 2014, the PCBs and metals on the Kiley Barrel Site were cleaned up by the Somerville Redevelopment Authority under TSCA and the MCP utilizing approximately $4.5 million in EPA and state cleanup funds. The cleanup included removal of the top three feet of PCB and metal contaminated soil and the placement of a three-foot soil cap. An in-situ ground water treatment and monitoring program has also been implemented to address low level chlorinated VOCs found at the northeast corner of the site. To prevent indoor air contamination from chlorinated VOCs, the building constructed on the Kiley Barrel Site will incorporate a sub-slab vapor mitigation system. An Activity and Use Limitation (AUL) or legal restriction recorded on the property title will be placed on the Kiley Barrel Site to ensure the cleanup solutions remain in place and only appropriate uses are allowed on the property over time. Remainder of the D2 Block Site investigations conducted by the Somerville Redevelopment Authority between 2004 and 2014 identified contamination on many of the parcels that comprise the Remainder of the D2 Block (i.e., the southern portion of the USQ Phase 1 Project Site). Since 2014, three rounds of field investigation consisting of more than 75 borings and soil testing have further characterized the site conditions. PCBs, metals, petroleum hydrocarbons and PAHs have also been identified in the soil. Investigations of groundwater did not identify any contamination requiring remediation. As part of the redevelopment, the contaminated Remainder of the D2 Block will be cleaned up under both TSCA, with oversight by the EPA, and the MCP, with oversight by the LSP. Additional testing will be performed and a cleanup plan for the PCBs will be submitted to EPA for approval before construction begins. Soil with PCB concentrations greater than EPA approved cleanup standards will be excavated and disposed of in an out of state landfill. The other contaminants, mostly associated with the historic fill, will be cleaned up under the MCP. The remediation plan will include a combination of soil removal and soil capping. During site preparation for construction activities, soil contaminated with metals, petroleum hydrocarbons and PAHs will be assessed, excavated and disposed of offsite or capped beneath new buildings in accordance with MCP regulations. Steps will be taken to control and monitor dust during construction. Lastly, like the Kiley Barrel Site, an AUL will be placed on the Remainder of the D2 Block. Through the regulatory process, which includes comprehensive testing, remediation plans, and construction monitoring in accordance with federal and state standards and with oversight by a LSP, the environmental challenges of the USQ Phase I Project will be remediated to make way for new places to work and live, supported by public open spaces for all to enjoy. If you have any questions about this process, please contact us at info@discoverusq.com. 2

3 Additional Information The following information is provided in response to specific questions from Somerville community members related to USQ Phase I Project environmental remediation. If the MEPA Phase 1 waiver is granted, will the site still be remediated? Yes. The D2 Block will be remediated as part of the USQ Phase 1 redevelopment in accordance with state and federal environmental regulations. The MEPA Phase 1 waiver will not change the scope or timing of the remediation. To finance the development, any project lender and investor would require site clean-up consistent with federal and state requirements. US2 and the Phase 1 project are no exception. What hazardous conditions existed on the site before the SRA s remediation efforts on the Kiley Barrel Disposal Site? The Massachusetts Department of Environmental Protection (MassDEP) assigns a Release Tracking Number (RTN) to all releases of oil or hazardous materials. The USQ Phase 1 Project Site includes 17 RTNs. Several of the RTNs are associated with the Kiley Barrel Site and the rest are associated with the Remainder of the D2 Block. US2 and the City/SRA are working with MassDEP to combine all the existing RTNs for the Remainder of the D2 Block into one RTN. Open releases related to any of the RTNs will be remediated and brought to closure in accordance with state and federal regulations as part of the redevelopment process. Kiley Barrel Disposal Site RTN Address(es) MAP ID Notification Date Status Contaminants of Concern Linked: Linked to Linked to Former Kiley Barrel Site Prospect St Somerville 258 Somerville 4 Milk Place 9 Milk Place 10 Milk Place 8 Bennett Street 14 Bennett Street Bennett Street 82-D-2 82-D-3 82-D-4 82-D-5 82-D D-34A 82-D D-37 3/15/1990 Phase V- REMOPS Metals, polycyclic aromatic compounds, PCBs, volatile organic compounds, chlorinated volatile organic compounds 7/12/1999 Closed linked. Arsenic Offsite properties 4/24/2009 Closed linked, Phase V Remainder of D2 Block Indoor Air and groundwater compounds from RTN RTN Address(es) MAP ID Notification Date Status Contaminants of Concern Bennett Court n/a 11/29/2003 Closed, RAO A-1 Hydraulic Fluid Allen Street 82-D D Allen Street 82-D D-22 6/1/2005 Closed, RAO Lead, PCBs, 1,4- dichlorobenzene 10/10/2004 Closed, RAO A-1 Petroleum hydrocarbons, Polycyclic aromatic hydrocarbons Bennett Street 82-D-33 8/30/2010 Closed, RAO A-3, AUL Metals Bennett Street 82-I-1A 12/9/2011 Tier 2, Phase II Arsenic, PCBs 3

4 Bennett Street 82-D-24 5/25/2012 Tier 2, Phase II Metals, Volatile organic compounds, polycyclic aromatic compounds Prospect Street 82-D D Allen Street 82-D D Bennett Street 82-I I-4 82-I-5 82-I I Prospect Street 30 Prospect Street 82-I-1 82-I-2 5/25/2012 Closed, RAO B-1 Metals, Volatile organic compounds, polycyclic aromatic compounds 5/25/2012 Tier 1D NAPL 8/8/2012 Tier 1D PCBs 8/8/2012 Tier 1D PCBs Milk Place 82-D-5 9/18/2013 Tier 1D Lead Bennett Street 82-I I-4 82-I-5 82-I I Allen Street 82-D D Bennett Street 82-D D D D Prospect Street 82-I-1 82-I-2 Petroleum based oil 4/23/2014 Tier 1D Metals, polycyclic aromatic hydrocarbons 4/23/2014 Tier 1D Metals, petroleum hydrocarbons, polycyclic aromatic hydrocarbons 4/23/2014 Tier 1D Metals, Petroleum Hydrocarbons, PCBs 4/23/2014 Tier 1D Metals Milk Place 82-D-5 4/23/2014 Tier 1D Metals Phenanthrene What was the extent of the Kiley Barrel Cleanup that was completed by the Somerville Redevelopment Authority (RTN )? The Kiley Barrel Disposal Site is being cleaned up the Somerville Redevelopment Authority (SRA). TRC of Lowell, Massachusetts is the Licensed Site Professional and environmental consultant for the cleanup. The Kiley Barrel Site was identified by MassDEP as a disposal site in 1990 due to the presence of elevated metals and petroleum hydrocarbons in soil and chlorinated VOCs in groundwater. Additional investigations identified contaminates attributed to the Kiley Barrel Site at eight contiguous properties (20-22 Prospect Street, Somerville Avenue, 9 and 10 Milk Place, 8, 14 and Bennett Street, and Bennett Street) and groundwater, soil gas, and indoor air at four downgradient properties (250 Somerville Avenue, 5-7 Allen Street, 9 Allen Street, and 13 Allen Street). In 2009, low concentrations of contaminants potentially associated with the Kiley Barrel Site were detected in the indoor air at the four downgradient properties. However, based on an MCP Method 3 risk characterization, the indoor air at these properties posed a condition of No Significant Risk and no additional measures regarding indoor air were required. In 2014, TRC, on behalf of the SRA, submitted a TSCA Risk-Based Cleanup Plan to the EPA for approval and an MCP Modified Remedy Implementation Plan (RIP) to the MassDEP. EPA approved the cleanup plan in October Between October 2014 and January 2015, the following cleanup activities were conducted at the Kiley Barrel Site: 4

5 Removal and off-site disposal of the top three feet of soil and replacement with clean backfill to provide a three-foot deep clean soil exposure barrier, including 6 inches of crushed stone as the finished pre-redevelopment surface. Removal and off-site disposal of soil deeper than three feet that contained total PCBs at concentrations equal to or greater than 50 milligrams per kilogram (mg/kg); Removal and off-site disposal of soil to the water table in an area in the northeast corner of the 14 Bennett Street parcel to remove VOCs; and Application of an emulsified vegetable oil remedial additive to the subsurface at the 14 Bennett Street and 250 Somerville Avenue parcels to enhance in-situ bioremediation of VOCs in groundwater. Groundwater monitoring continues to gauge the effectiveness of the enhanced bioremediation. An AUL will be placed on the Kiley Barrel Site to ensure the cleanup solutions remain in place and only appropriate uses are allowed on the property over time. What hazardous condition currently exist on the site? Residual contaminants at the Kiley Barrel Site remain under the 3-foot cap. The contaminants on the Remainder of the D2 Block are PCBs, metals, petroleum hydrocarbon and PAHs in soils. Groundwater contamination requiring remediation has not been identified south of the Kiley Barrel Site. What is the plan for remediation in connection with the USQ Phase 1 Project? Similar to the Kiley Barrel Site, for the Remainder of the D2 Block, US2 s Licensed Site Professional will submit a TSCA Risk Based Cleanup Plan to EPA for approval and a Release Abatement Measure (RAM) Plan to the MassDEP. Once EPA approves the Cleanup Plan, US2 will conduct the cleanup. Soil with PCB concentrations greater than the EPA and MassDEP cleanup standards will be excavated and disposed off-site at an out-of-state landfill. Following PCB cleanup in accordance with the EPA approved and during site preparation for building construction, additional cleanup of metals, petroleum hydrocarbons and PAHs will continue under a RAM with LSP oversight. A RAM Plan will be prepared for the both the Kiley Barrel Site and the Remainder of the D-2 Block for managing contamination during building construction. Regular status report will be submitted to the MassDEP. During construction, soil contaminated with metals, petroleum hydrocarbons and PAHs will be assessed, excavated and disposed off-site, or capped beneath the new buildings in accordance with state regulations. In addition, a sub-slab vapor mitigation system will be incorporated into the building constructed on the Kiley Barrel Site. Steps will be taken to control and monitor dust during construction. Following completion of the development, an AUL will be placed on the properties that requires maintenance of the cap and permits the new uses on the site. What is the schedule for remediation in connection with the USQ Phase 1 Project? Assuming that the requested Phase 1 waiver is granted and the USQ Phase 1 Project is proceeding according to schedule, additional site characterization will be performed in the fall of 2018 to better refine the current understanding related to PCB contamination on the Remainder of the D2 Block. Additional testing will also be done for metals, petroleum hydrocarbons and PAHs. Following the site characterization, a TSCA Risk Based Cleanup Plan will be prepared, incorporating the new data, and submitted to EPA for approval. Following EPA approval, the PCB cleanup will be performed, likely in early Thereafter, additional cleanup of metals, petroleum hydrocarbons and PAHs will be performed during site preparation and excavation as part of building construction. These activities are 5

6 projected to occur during the first six months of construction. The AUL will be prepared and recorded on the property title once construction is complete. Can you provide more information about the existing AUL at 26 Bennett Street? 26 Bennett Street is centrally located within the Remainder of the D2 Block and is approximately 3,841 square feet in area and approximately 2% of the overall D2 Block (highlighted in orange on the image to the right). There is an existing AUL on 26 Bennett Street which is a MassDEP disposal site (RTN ). The property achieved regulatory closure with A Class A-3 Response Action Outcome (RAO) Statement in The primary contaminants of concern are metals, including antimony, barium, cadmium, chromium, lead, nickel, vanadium and zinc; and very low levels of PCBs in soil. The source of the contamination has been attributed to releases associated with the Kiley Barrel Site (RTN ) located adjacent to the Property, and historic fill. To maintain a condition of No Significant Risk, the AUL that is currently on record for this site: allows activities and uses consistent with commercial, industrial or passive recreational uses; prohibits residential, child day care, child school, institutional, playground and active recreational use; and requires all site soil to be covered with a protective barrier such as a building, asphalt pavement, concrete or at least two inches of gravel to impede direct contact to soil. As part of the redevelopment, the 26 Bennett Street portion of the property will be remediated to the same standards as the Remainder of the D2 Block. Prior to and during construction, the most highly contaminated soils will be excavated and transported off-site for disposal. The remaining contaminated soil will be capped with new on-site buildings or paving. After remediation activities are completed, the existing 26 Bennett Street AUL will be superseded by a new project-wide AUL (inclusive of 26 Bennett Street) will be recorded that requires maintenance of the cap and permits the new uses on the site. *** END OF BRIEFING *** 6

7 KILEY BARREL DISPOSAL SITE (RTN ) REMAINDER OF D-2 BLOCK (Multiple RTNs) LEGEND: KILEY BARREL DISPOSAL SITE (RTN ) REMAINDER OF D-2 BLOCK (Multiple RTNs) BLOCK D-2 REVITALIZATION BOUNDARY BLOCK D-2 PARCEL BOUNDARY MASS DEP RTN DISPOSAL SITE BOUNDARY RTN RELEASE TRACKING NUMBER NOTES: 1. 0 BASE PLAN FROM "BLOCK D-2 LLC, UNION SQUARE REVITALIZATION PROJECT, SOMERVILLE, MA, BLOCK D-S MassDEP DISPOSAL SITE BOUNDARIES," FIG. 2.0, PREPARED BY STANTEC. 60 Approximate Scale, Feet 120 Union Square Revitalization Project Somerville, Massachusetts Union Square US2 Somerville, Massachusetts Consultants Project BLOCK D-2 MASSDEP DISPOSAL SITE BOUNDARIES August 2018 Fig. 1 \\geiconsulta B:\Working\UNION SQUARE - US2\ Union Square Parcel D2\00_CAD\Figures\Report\ dwg - 8/20/2018