SITE INFORMATION AND CORRESPONDENCE_CASE 2 FILE 2

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Case Closure Summary Former Shell Service Station Page 2 of 3 04/27/98 Date of Well Installation Report on installation of MW1- MW3 in March 1998. Report of findings: Soil samples collected at 15.5 — 16.5 feet bgs in MW-1; located adjacent to the former USTs, contained concentrations for methyl tertiary-butyl ether (MTBE) at 220 pg/kg, TPH-g at 14 mg/kg, ethyl benzene at 0.016 mg/kg, and total xylenes at 0.053 mg/kg; soil samples collected at 21-22.5 feet bgs in MW-1 contained methanol at 3.2 mg/kg; and soil samples collected at 26-27 feet bgs in MW-1 contained methanol at 1.1 mg/kg, TPH-g at 19 mg/kg, toluene at 0.02 mg/kg, and total xylenes at 0.17 mg/kg. Soil samples collected at 13-15 feet bgs in MW-2, located in the southwest corner of the property, contained concentrations for methanol at 1.2 mg/kg. Soil samples collected at MW- 3, located southeast of the former. USTS near the dispenser island along Main Street,were non-detect for chemicals of concern. 04/28/98 Quarterly groundwater monitoring began this date. Initial groundwater analytical results indicated concentrations for TPH-g at 280 pg/L, benzene at 0.5 pg/L, ethyl benzene at 0.84 µg/L, total xylenes at 0.59 µg/L, and MTBE at 120 µg/L. Methanol, ethanol, tertiary-butyl alcohol (TBA), di- isopropyl ether (DIPE), ethyl tertiary butyl ether (ETBE), tertiary-amyl methyl ether (TAME), and toluene were not detected in any groundwater samples. 06/30/00 Date of Well Receptor Survey report. One municipal well is located i approximately 1,500 feet south of the site and several domestic wells were identified within a 2000-foot radius of the site. Also a school is located in close proximity to the site. 12/5,6,7/00 Advanced six cone penetrometer test borings to total depths of approximately 45 feet bgs. Soil samples collected at 13-15, 18-20, and 33 feet bgs from each boring were non-detect for chemicals of concern. With the exception of MTBE detected at 1.6 pg/L in groundwater sample CPT- 3 collected at 24 feet bgs, the remaining 17 grab groundwater samples, collected from the six CPT borings, were non-detect for chemicals of concern. i i