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ASSOCIATESC\TATC I NC , hydrocarbons. The work is summarized in ATC's Summary Report of Subsurface Investigation, dated June 17, 1998. On September 21, 1998, an ATC geologist supervised the advancement of five soil borings to depths ranging from 5 to 31 feet below ground surface (bgs). Soil borings SB7 through SB 11 were placed south and east of former boring SB6 and contained detectable concentrations of petroleum hydrocarbons. Analytical results of soil samples indicated the presence of petroleum hydrocarbons. One groundwater sample was collected from each boring at the depth groundwater was first encountered. Groundwater samples indicated the presence of petroleum. hydrocarbons. Results are summarized in ATC's Summary Report of Additional Subsurface Investigation, dated November 4, 1998. On January 27, 1999, an ATC geologist supervised the advancement of two soil borings, MW1 and MW3, to 35 feet bgs and one continuous core soil boring, MW2, to 45 feet bgs. Analytical results for the soil samples indicated the presence of petroleum hydrocarbons in boring MW2 located in the center of the former UST location. The groundwater wells were developed and sampled and the groundwater samples from wells MWl and MW2 contained detectable concentrations of petroleum hydrocarbons. Results are summarized in ATC's Summary Report of Additional Subsurface Investigation, dated April 7, 1999. On July 15, 1999, an ATC geologist supervised the advancement of two soil borings, MW4 and MW5, to 36.5 feet bgs. Analytical results for the soil samples contained no detectable concentrations of petroleum hydrocarbons. Groundwater wells MW4 and MW5 were developed and sampled and samples were submitted to a State-certified laboratory. Groundwater analytical results are pending. SCOPE OF WORK 24-Hour Pumping Test ATC proposes to perform a one-day low-rate pumping test on well MW2 (Figure 2). PHS/EHD will be notified at least 48 hours in advance of performing any fieldwork. Prior to beginning the pump test, ATC personnel will measure depth to water in all on-site wells and collect one groundwater sample from well MW2. ATC will also collect one groundwater sample from well MW2 after the 24-hour pump test has been completed. The groundwater samples will be placed on ice and submitted to a State-certified laboratory for analysis of total petroleum hydrocarbons as diesel (TPHd), total petroleum hydrocarbons as gasoline (TPHg), benzene, toluene, ethyl benzene, xylenes (BTEX), and oxygenate fuel additives by the appropriate EPA methodologies. A pump equipped with a flow meter, totalizer, and discharge hose will be installed into well MW2. During the test, ATC will also place transducers in the extraction well MW2 and observation wells MW1, MW3, and MW4 to measure and tabulate the depth to water in observation wells at frequent intervals. Because well MW5 is located across Acacia Street which w:ll 30991reportslpumpwkp.doe 2