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HomeMy WebLinkAboutMobil Station - 189 Chauncy St. - 12/10/2015rs9tli6CltV$tef' be Frivironmental Services, Inc. 364 Llttl®son Road • Suilo 4 , Westrord. Massachusetts 01886 > 00) 221.6119 > rax 10781 392-8583 December 10, 2015 Mr. Scott Leite Health Agent Mansfield Health Department 6 Park Row Mansfield, MA 02048 Certified Matl DEE Subject: Public Notice Requirement — Permanent Solution (With No Conditions) Mobil Service Station No. 1502 189 Chimney Street Mansfield, Massachusetts Release Tracking Number (RTN) 4-19836 Dear Mr. Leite: On behalf of Global Companies, LLC (Global), Groundwater & Environmental Services, Inc. (GES) is informing you that a Permanent Solution (With No Conditions) has been achieved for Mobil Service Station No. 1502 located at 189 Chauncy Street in Mansfield, Massachusetts. The report is being filed with the Massachusetts Department of Environmental Protection (MassDEP) Southeast Regional Office. Public involvement provisions [310 CMR 40.1400] of the Massachusetts Contingency Plan (MCP) require that the Chief Municipal Officer and Board of Health in the community in which a disposal site is located be notified when these reports are being submitted to the MassDEP. In addition, per MCP requirements, a map of the disposal site boundary (Figure 1, Area Subject to Permanent Solution) and a summary of the report conclusions are also attached. If you have any questions regarding this submittal, please contact the undersigned at (800) 221-6119 x3252. Sincerely, GROUNDWATER & ENVIRONMENTAL SERVICES, INC Stefan C. Sokol, LSP Senior Project Manager Attachments cc: Global File Note: This report is also available for on-line review at MassDEP's website (http://public.dep.state.ma.us/fileviewer/Rtn.aspx?rtn=4-0019836). PERMANENT SOLUTION REPORT (WITH NO CONDITIONS) SUMMARY & CONCLUSIONS Mobil Service Station No. 1502 189 Chimney Street Mansfield, Massachusetts MassDEP RTN 4-19836 On behalf of Global Companies LLC (Global), Groundwater & Environmental Services, Inc. (GES) is submitting this Class C-2 Response Action Outcome (RAO) for Mobil Station No. 1502, located at 189 Chauncy Street in Mansfield, Massachusetts (the "Mobil station property"). The Mobil station property is the location of a release of petroleum (gasoline), as defined in the Massachusetts Contingency Plan (MCP), 310 CMR 40.0000, and is identified by the Massachusetts Department of Environmental Protection (MassDEP) as Release Tracking Number (RTN) 4-19836, The Permanent Solution Report was prepared in accordance with applicable requirements specified in the MCP regulations. Activities associated with RTN 4-19836 were initiated on June 6, 2006, when the gasoline underground storage tank (UST) piping system failed a routine tightness -test, requiring a 72-hour notification to MassDEP as a potential threat of release. The source of the potential release (subsurface piping enclosed in a FiberTrench® system) was repaired and a follow-up Immediate Response Action (IRA) investigation was completed that included limited soil excavation, soil sampling, subsurface assessment, confirmatory groundwater sampling, a sensitive receptor survey, and screening of nearby utilities. The following summarizes the findings of the report: The Mobil station property is located in a densely developed mixed -use (commercial and residential) area. The subject property has been owned/operated as a gasoline service station since at least 1961. Historical environmental reports indicate that at least two station configurations existed at the Mobil station property: one existing prior to 1989 and one that represents the current configuration following a station rebuild in 1989. The Mobil station property was expanded in 1989 when it was combined with an adjacent former residential parcel to the north. The station building that currently exists was built in the newly -developed northern portion of the enlarged property and the current tank field is located in an area formerly occupied by a small concrete building and attached wooden shed. The Mobil station property and downgradient area is also the location of a historical release condition associated with MassDEP Site No. 4-0914, for which a Class B-1 Response Action Outcome (RAO) was filed in October 1995. By definition, a Class B-1 RAO implies that concentrations at the time were above background levels, but that no remedial activities were performed because a level of No Significant Risk had already been achieved. In preparing the current Permanent Solution Report, consideration was given to historical conditions on these properties that were known to exceed background levels when the Class B-1 RAO was achieved. The "Disposal Site," or area where site related impacts have come to be located, includes the soutlr/central portion of the Mobil station property and a portion of Chauncy Street to the south (refer to Figure 1). The Disposal Site and surrounding properties are located within a medium -yield Potentially Productive Aquifer, which is considered a Potential Drinking Water Source area. However, the subject property and surrounding properties are served by the municipal water supply. No GROUNDWATER & ENNVIRONMENTAL SERVICES, INC. Page 1 of 2 Permanent Solution Repoil - Summary & Conclusions Mobil Station No. 1502 Mansfield, MA 12/10/2015 public water supply wells or private water supply wells are located, respectively, within a half - mile and 500 feet of the Disposal Site. Residential properties with basements border the subject property to the east and to the southeast (cross -gradient to downgradient) across Chauncy Street. The closest residential property with a basement is located approximately 50 feet east of the Disposal Site, and abuts the subject property. Based on groundwater sampling and the direction of groundwater flow, there is no potential for vapor intrusion into indoor. Based on soil sampling to date, residual petroleum impacts appear to exist primarily in the gasoline dispenser area in the southern central portion of the Mobil station property, and to the south of the dispensers. Residual impacts are also encountered downgradient in the Chauncy Street right-of-way which may be related to previous release conditions under MassDEP Site No. 4-0914, or are potentially attributable to off -site conditions unrelated to the Mobil station. During the initial IRA investigation, there appeared to be little or no evidence that significant soil impacts extended beyond and outside of the FiberTrench© system on the Mobil station property. Light non -aqueous phase liquid (LNAPL) has never been reported site monitoring wells. Currently, groundwater concentrations are not detected. From the period of 2012 to 2015, Exposure Point Concentrations (EPCs) do not exceed the MCP Method 1 GW-1 groundwater standards (protective of groundwater as a source of drinking water), GW-2 groundwater standards (protective of potential vapor intrusion into indoor air), or GW-3 groundwater standards (protective of potential discharge to surface water), and therefore, do not present a risk. Significant groundwater impacts historically have not extended beyond the Mobil station property. A Representativeness Evaluation and Data Usability Assessment was completed to document the adequacy of spatial and temporal data sets used to support the Permanent Solution, and to establish that the data is scientifically valid and defensible, and of a sufficient level of precision and accuracy and completeness to support the submittal. A Method 1 Risk Characterization was conducted which focused on possible exposures to Human and Environmental Receptors. Under current and foreseeable future site conditions, a condition of No Significant Risk has been achieved with respect to risk of harm to human health, safety, public welfare and the environment. • The Permanent Solution Report (with No Conditions), categorically applies to Disposal Sites where: Requirements of 310 CMR 40.1040(1) of the MCP have been achieved; Oil and/or hazardous material (OHM) concentrations do not exceed an applicable Upper Concentration Limit (UCL) in soil or groundwater, unless such levels are consistent with Natural Background; A level of No Significant Risk exists and will be maintained for all current and foreseeable future use of the site without relying upon assumed limitations on current or future site activities; and Response actions have eliminated all threats of release. GROUNDIYATER & ENN VIR ONMENTAL SERVICES, INC, Page 2 of 2 Permanent Solution Repoii - Summary & Conclusions Mobil Station No. 1502 Mansfield, MA 12/10/2015 V Y ! >t C — \\ WOO FORMER- J T --__ ? — uc — uc �,—cFORMER PROPERTY —c 0 1L w -_ Qw 0�I i II (D- I r" Paz I II I I O/W-, MWa s of • B2-UNDARY fur v 03 uc — U — MOBIL l C�� ,; � STATION �9 ATER E14 " OIL/W MW4 / SEPARATOR DUMPSTER ® N I ENCLOSURE s 1 MW3 OW1 FORMER 989\®OW2/ ATI N 100 NI l c .) „F\ e� 1 �01-06 Jf� FORM R s I 1989E UST G o 4 III L ONPCDETE b PHONE 8O 9MW2 EJNO 14-5 018PENI 1989 S601MW101/00 \ \ E/ 'a MW1 B `Vs69� '? I )\ — olw r ° �Wi '7 t? 9 MW102 \ '^o —1 `:,� M �h OI1U C Ill ss w eOW6 1 BASED ON Al LAND TITLE AND PARTIAL TOPOGRAPHIC SURV PROVIDED BY EXXONMOBIL OIL CORPORATION, DECEMBER 26, 2002. HISTORICAL FEATURES OBTAINED FROM PROPOSED SITE PLAN, GALE ASSOCIATES, INC., DECEMBER 1, 1988 REVISION. m (®R WELL LOCATIONS ADDED BY GES. AREA SUBJECT TO PERMANENT SOLUTION LEGEND -- •- — PROPERTY BOUNDARY [o[W] OIL/WATER SEPARATOR Lo 1,000 GAL USED OIL UST ® CATCH BASIN ® UTILITY MANHOLE UTILITY POLE 0 LIGHT POLE CHAIN LINK FENCE IC=7 DISPENSER ISLAND DRYWELL FOR CANOPY FIRE HYDRANT • TANK FIELD WELL ® FIBER TRENCH CLEANOUT 9 MONITORING WELL FQ DESTROYED/ABANDONED WELL --s — — UNDERGROUND SANITARY SEWER LINE --�-- UNDERGROUND STORM SEWER LINE —-- UNDERGROUND ELECTRIC LINE — — UNDERGROUND WATER LINE =�-- UNDERGROUND GAS LINE — OVERHEAD UTILITIES --- UNDERGROUND STORM SEWER LINE —'— — UNDERGROUND TELEPHONE LINE SOIL BORING (2008) 11 SOIL BORING (2014) u"^--- DRAFTED BY: W.G.S. AREA SUBJECT TO PERMANANT SOLUTION /EI I S 2 HRMEWED MOBIL SERVICE STATION #1502 s, -- Mtvs 189 CHAUNCY STREET SI s,- 'r MANSFIELD, MASSACHUSETTS NORTH Groundwater & Environmental Services, Inc. � i 364 LITTLETON ROAD SUITE 4 WESTFORD, MA 01886 0 APPROXIMATE 30