EXECUTIVE SUMMARY. The following is our conclusions of the environmental issues at the Site based on our investigations:

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Mavis Pearson
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1 EXECUTIVE SUMMARY Engineers, Inc. (), on behalf of the Town of East Lyme, Connecticut performed a Phase II Environmental Site Assessment (Phase II ESA) on the property located at 224 Main Street (the Site ) in the Niantic section of East Lyme, Connecticut. The Phase II ESA was conducted to support the Town s efforts to evaluate the environmental conditions of this property prior to potential purchase. was not performing this investigation for verification and sign-off by a Connecticut Licensed Environmental Professional (LEP); however all fieldwork was performed to be consistent with the following performance standards: the Remediation Standard Regulations (RSRs) established by the Connecticut Department of Environmental Protection (CTDEP), the CTDEP s September 2007 Site Characterization Guidance Document (SCGD), and the Significant Environmental Hazard Condition Notification Statute established by the CTDEP. previously completed a Phase I Environmental Site Assessment (ESA) for the Site in September The Site has been utilized as a gasoline service station since circa Several generations of underground storage tanks (USTs) have been used on-site and documented releases to soil and groundwater has been reported. The southwest section of the Site was also historically utilized by a railroad station. A Conceptual Site Model (CSM) was prepared that identified eleven Recognized Environmental Concerns (RECs) related to the current and former uses of the Site. The Phase II ESA study was performed to determine the absence or presence of regulated compounds in the soil and/or groundwater that may have resulted from releases of oil and/or hazardous substances at each of the RECs identified in the CSM. The study would also help confirm whether or not other orphan UST(s) exist at the Site. The activities conducted as part of the Phase II ESA study included a geophysical survey, the advancement of fourteen soil borings, the installation of three new groundwater monitoring wells, the collection of a shallow hand-bore soil sample, the sampling of groundwater from four previously existing and three new groundwater monitoring wells, and the collection and analysis of soil and groundwater samples. The following is our conclusions of the environmental issues at the Site based on our investigations: The geophysical survey identified two magnetic anomalies consistent with abandoned USTs at the northwest section of the Site. The survey also identified relatively shallow linear anomalies suspected of being former fuel transfer piping extending from a former pump island at the northwest section of the Site to the two aforementioned magnetic anomalies suspected of being abandoned USTs. The location of these anomalies match well with two USTs previously identified on Sanborn Maps that were documented in our Phase I ESA study. The previous ground penetrating radar survey contained in the Geotechnical Services, Inc. technical report from April 2010 did not reveal these anomalies. Evidence of a petroleum and/or chemical release has been identified at the following RECs: ES-1

2 REC-1 (Sanborn Mapped USTs): Extractable total petroleum hydrocarbons (ETPH) was detected in groundwater at well MW-5 at 0.16 milligrams per liter (mg/l), which exceeds the CTDEP standard of 0.1 mg/l. Moderate to strong gasoline-impacted soils with photoionization detector (PID) readings exceeding 1,000 parts per million (ppm) were observed during the drilling of this well between feet (ft) below the ground surface (bgs), and at nearby boring B-10 (21-22 ft bgs). Both MW-5 and B-1 are situated immediately downgradient of the two Sanborn mapped USTs. The geophysical survey corroborates the possibility of two orphan USTs existing in the same general area. Another soil boring was completed upgradient of the magnetic anomalies suspected of being abandoned USTs (B-3), and there were no signs of visual or olfactory impacts or PID detections similar to what was observed at MW-5 and B-10. Based on this information, the magnetic anomalies suspected of being orphan USTs should be further evaluated. REC 2 (Former Pump Islands & Ancillary Piping): Leachable lead was detected in shallow soils (1-3 ft bgs) at B-6 at mg/l, which exceeds the CTDEP standard of mg/l. No visual or olfactory signs of petroleumimpacted soils or elevated PID readings were observed during the drilling of this boring. REC-2 and REC-5 each present some potential as being the source for the leachable lead impacts discussed above; however the shallow nature of these impacts and nature of chemical constituent suggests the former pump island is the most likely source. The horizontal and vertical extent of the impacts identified at this REC has not been delineated. REC 3 (Former Service Station Building): Leachable lead was detected in subsurface soils (6-10 ft bgs) at B-10 at mg/l, which exceeds the CTDEP standard of mg/l. No visual or olfactory signs of petroleum-impacted soils or elevated PID readings were observed during the drilling of this boring. Based on the level of testing completed to date, REC-3 may potentially be contributing to the leachable lead impacts discussed above. Other RECs potentially contributing to the impacts described above include REC-1 and REC-9. The horizontal and vertical extent of the impacts identified at this REC has not been delineated. Moderate to strong gasoline-impacted soils with PID readings exceeding 1,000 ppm were also observed during the drilling of boring B-10 between ft bgs. Given the depth these observations were noted at, combined with similar observations noted at B-1/MW-5, we suspect these impacts are related to REC-1. REC 6 (Former 5,000 Gallon USTs): Leachable lead was detected in subsurface soils (7-9 ft bgs) at B-8 at mg/l, which exceeds the CTDEP standard of mg/l. No visual or olfactory signs of petroleum-impacted soils or elevated PID readings were observed during the drilling of this boring. Based on the level of testing completed to date, REC-6 may potentially be contributing to the leachable lead impacts discussed above. Other RECs potentially contributing to the impacts described above include REC-9. The horizontal and vertical extent of the impacts identified at this REC has not been delineated. ES-2

3 REC 7 (Former 2,000-Gallon UST): Several types of volatile organic compounds (VOCs) have been identified in deep subsurface soils (22 ft bgs) at B- 2 above applicable CTDEP standards. ETPH has also been detected in groundwater at the same location (MW-6) at 0.36 mg/l, which exceeds the CTDEP standard of 0.1 mg/l. Moderate to strong gasoline-impacted soils with PID readings exceeding 1,000 ppm were observed during the drilling of this well between ft bgs. REC-5, REC-7 and REC-8 all seem to be potential sources for these impacts, but a review of other surrounding soil and groundwater data suggests REC-7 is the most likely contributor. The previously removed UST system comprising REC-7 had a historic release documented in 1994 that caused the Site s inclusion on the CTDEP s LUST database. A previous UST closure report in 1994 from Apex Environmental, Inc. documented gasoline-related constituents in one closure sample exceeding applicable CTDEP criteria. A subsequent Phase II report completed in 2005 from Lenard Engineering, Inc. also documented in the same area VOC impacts in subsurface soils exceeding applicable CTDEP criteria, and both VOC and ETPH impacts in groundwater exceeding applicable CTDEP criteria. The horizontal and vertical extent of the impacts identified at this REC has not been delineated. REC 9 (Former Septic Tank and Dry Well): Leachable lead was detected in subsurface soils (8-10 ft bgs) at B-7 at 0.20 mg/l, which exceeds the CTDEP standard of mg/l. The detection of semi-volatile organic compounds (SVOCs) and ETPH in the same boring also provide further evidence of a petroleum release at this REC. No visual or olfactory signs of petroleum-impacted soils or elevated PID readings were observed during the drilling of this boring. Based on the level of testing completed to date, REC-9 presents some potential for being the source for the leachable lead impacts discussed above. Other RECs potentially contributing to the impacts described above include REC-3 and REC- 6. The horizontal and vertical extent of the impacts identified at this REC has not been delineated. REC-11 (In Use 275-Gallon Fuel Oil AST) ETPH was detected in surface soils at hand auger sample HB-1 at 2,200 milligrams per kilogram (mg/kg), which exceeds the CTDEP standard of 500 mg/kg. No odors, staining or elevated PID readings were observed at this sample location. The extent of this release (both horizontally and vertically) has not yet been determined. In addition, the aboveground storage tank (AST) appears to reside on adjoining land owned and operated by the railroad company. Groundwater at MW-7 was sampled and found impacted with several SVOCs at concentrations exceeding applicable DEP groundwater standards. The previous Phase I ESA report did not identify any features or operations considered an REC, and there were no SVOC exceedences identified in soil or groundwater at any of the RECs found on- Site. Although additional studies would be needed to confirm this, it is possible these impacts could be attributable to an upgradient, off-site source. also identified one noteworthy limitation. The Phase II ESA study does not evaluate subsurface conditions beneath or immediately downgradient of the ES-3

4 existing convenience store building. This building is considered a REC because of it past use for automotive repair activities and possibility that features related to past operations (i.e. hydraulic lifts, oil/water separators, floor drains, dry wells, etc) were abandoned beneath the building slab. To evaluate this REC, the scope of work would have included a geophysical survey, advancement of soil borings and completion of a new groundwater monitoring well inside the building, and doing these activities would likely have caused significant disruption if not temporary closure of the convenience store business, which was not possible. Subsurface conditions immediately south of (downgradient) the convenience store building also couldn t be evaluated because the land appears to be owned by the railroad company and a trans-continental fiber optic cable exists in the area. As previously stated, the RSRs are typically used for all sites undergoing environmental investigations as a baseline to evaluate a site s potential environmental liability. However, the subject Site, to the best of our understanding, is not obligated to meet numeric criteria established in the RSRs because it is not entered into any type of CTDEP remedial program, there is no CTDEP enforcement action (i.e. Notice of Violation, Consent Order, etc.) being taken against the property, and none of the soil or groundwater data compiled as part of this assessment triggers any reportable condition pursuant to the CTDEP s Significant Environmental Notification Statute (CGS 22a-6U). Because of these circumstances, although several exceedences of CTDEP cleanup criteria were documented, the Site technically is not required at this time to comply with the RSRs nor is remediation of soil or groundwater required. The Site; however, is not completely outside of CTDEP jurisdiction. The gas station is a registered UST site, which means they are subject to CTDEP UST regulations. Current CTDEP UST regulations will require the in-use USTs to be removed once they exceed their useful life expectancy. If the Site was to be redeveloped and the gas station activities discontinued, the USTs would need to be removed. The UST regulations require CTDEP to be notified of the tank removal activities, require the collection of confirmatory soil samples from each tank grave to determine if there was a leak, and require closure documentation be submitted to the CTDEP. If signs of a release/leak are found, a spill report has to be filed with the CTDEP. The Site is also documented on the CTDEP s LUST database, and the database lists this LUST case as open and Clean Up Initiated. Given the fact that this release was first encountered in 1994 and soil and groundwater impacts continue to be discovered above CTDEP criteria in 2010, it is obvious the nature and extent of impacts from this historic release has not been properly delineated nor has it been cleaned up to CTDEP standards. Should the CTDEP become aware of this, not only could they force the Site owners to comply with RSR criteria, they could also levy financial penalties given it has been over 15 years since the leak was first discovered. Given these circumstances, recommends the following: Consultation with an environmental attorney familiar with state and federal environmental laws should be sought if the Town desires to move forward with the purchase of this property in order to accurately determine the full extent of environmental liability the Town will assume from land transaction. The Town should also consider developing language into the purchase and sale agreement that stipulates the current owners be completely responsible (i.e. they become the certifying party) for all ES-4

5 environmental investigations and/or remediation that are needed at this site, regardless of whether or not the work is required by the RSRs. Perform a focused Phase III ESA to delineate the horizontal and vertical extent of impacts previously identified at REC-1, REC-2, REC-3, REC-6, REC-7, REC-9 and REC-11. This study should also evaluate subsurface conditions beneath or immediately downgradient of the existing convenience store building and re-sampling groundwater MW-7 to confirm the previously identified SVOC exceedences. Perform a test pit in the area of the two suspected orphan USTs identified from geophysical survey. Significant care should be taken during the test pitting activities to avoid damaging any potential USTs systems that may exist in this area. If USTs are present, these tanks would need to be registered with the CTDEP, they would need to be removed and properly disposed of, and a release assessment including collection of confirmation soil samples from each tank grave would need to be performed. This closure documentation would have to be submitted to the CTDEP. If there are signs that a UST is leaking or leaked historically, notification to the CTDEP s Oil & Chemical Spills Response Division would be required. As contained in the Phase I ESA, in the event of demolition or redevelopment activities, Weston and Sampson recommends that asbestos containing materials (ACM) and lead based paint (LBP) be sampled to determine content prior to demolition or renovation activities. During renovation or demolition activities, workers should follow the Occupational Safety and Health Administration (OSHA) regulations regarding potential exposure to ACM and LBP. R:\East Lyme CT\224 Main Street, Niantic\Phase II ESA\Report\FINAL Phase II ESA Report.doc ES-5

Memorandum. Rian Amiton; City of Brockton Planning Department. John McRobbie and Thomas Biolsi; TRC Environmental Corporation

Memorandum. Rian Amiton; City of Brockton Planning Department. John McRobbie and Thomas Biolsi; TRC Environmental Corporation TRC Wannalancit Mills 650 Suffolk Street Lowell, Massachusetts 01854 Main 978.970.5600 Fax 978.453.1995 Memorandum To: From: Subject: Rian Amiton; City of Brockton Planning Department John McRobbie and