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(Vv:ATC Results are summarized in ATC's Summary Report of Additional Subsurface Investigation, dated June 1, 1999 On September 12, 2001, and October 4 and 5, 2001, a geologist from ATC supervised the advancement of six soil borings, S137 through SB 12, to approximately 20 to 25 feet bgs and one cone penetration test (CPT) boring to approximately 45 feet bgs Analytical results of soil samples indicated no detectable presence of petroleum hydrocarbons or fuel oxygenates One groundwater sample was collected from each boring at the depth groundwater was first encountered Groundwater samples indicated no detectable presence of petroleum hydrocarbons or fuel oxygenates Results are summarized in ATC's Summary Report of Supplemental Subsurface Investigation, dated January 4, 2002 On July 16 - 18, 2002, an aquifer test was conducted over a 48-hour period by extracting groundwater at a generally constant rate from well MW i The test was performed to determine the aquifer properties and the radius of influence (ROI) for groundwater pumping The groundwater extraction pilot test yielded a pumping rate of approximately 4 76 gpm and a ROI of up to 85 feet Results are summarized in ATC's Feasibility Study Report, dated December 12, 2002 SAMPLING ACTIVITIES On September 10, 2003, ATC personnel collected groundwater samples from monitoring wells • MW1, MW2, and MW3 The locations of the monitoring wells are shown on Figure 2 Prior to collection of groundwater samples, the depth to water, pH, electrical conductivity, and temperature were measured in the monitoring wells and recorded A minimum volume of three well casings was purged from each well prior to sampling The wells were allowed to recover and samples were collected from each well using disposable bailers The groundwater samples collected from each well were submitted to State-certified Argon Laboratories (ELAP Cert No 2359) for chemical analyses of total petroleum hydrocarbons as gasoline (TPHg) utilizing EPA Method 801513, benzene, toluene, ethylbenzene, xylenes (BTEX) utilizing EPA Method 8021 B, and gasoline oxygenates/additives including methyl tertiary butyl ether (MTBE), ethyl tertiary butyl ether (ETBE), di-isopropyl ether (DIPE), tertiary butyl alcohol (TBA), tertiary amyl ether (TAME), 1,2-dichloroethane (1,2-DCA), and 1,2-dibromoethane (EDB) by EPA Method 8260B Groundwater well purge and sample logs are contained in Attachment 1 ANALYTICAL RESULTS The laboratory analytical results indicate TPHg and BTEX were detected in the groundwater sample collected from monitoring well MW 1 at concentrations of 4,000 micrograms per liter (pg/L), 14 µg/L, 1 5 pg/L, 50 pg/L, and 16 pg/L, respectively None of the gasoline oxygenates/additives were detected in the sample collected from MW 1 TPHg was detected in the groundwater sample collected from monitoring well MW2 at a concentration of 300 µg/L BTEX constituents were not detected in this sample TBA was detected in . the sample collected from MW2 at a concentration of 120 pg/L s�enVlronrnentalt149811Reportsl3QR-03 doc 2