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A S S O C I A T E S I N C <br /> On November 14, 1997, a geologist from ATC Associates supervised the advancement of two <br /> soil borings to 30 feet below ground surface (bgs). Analytical results of soil samples indicated the <br /> presence of petroleum hydrocarbons. One groundwater sample was collected from each boring at <br /> the depth groundwater was first encountered, approximately 30 feet bgs. Groundwater samples <br /> indicated the presence of petroleum hydrocarbons. Results are summarized in ATC's Summary <br /> Report of Subsurface Investigation, dated January 14, 1998. <br /> On July 13, 1998, a geologist from ATC Associates supervised the advancement of four soil <br /> borings to 26 to 31 feet bgs. Analytical results of soil samples indicated the presence of <br /> petroleum hydrocarbons. One groundwater sample was collected from each boring at the depth <br /> groundwater was first encountered. Groundwater samples indicated the presence of petroleum <br /> hydrocarbons. Results are summarized in ATC's Summary Report of Additional Subsurface <br /> Investigation, dated September 9, 1998. <br /> On February 18, 1999, a geologist from ATC Associates supervised the installation of three <br /> groundwater monitoring wells from 39 to 41 feet bgs. Soil borings MW1, MW2, and MW3 were <br /> completed as two-inch monitoring wells. One soil sample from each boring was collected and <br /> after the groundwater monitoring wells were developed on groundwater sample was collected <br /> from each well. Soil and groundwater samples contained detectable concentrations of petroleum <br /> hydrocarbons. Results are summarized in ATC's Summary Report of Additional Subsurface <br /> Investigation, dated June 1, 1999. <br /> In September and October 2001, a geologist from ATC Associates supervised the advancement of <br /> six off-site soil borings to approximately 25 feet bgs. Analytical results of soil and groundwater <br /> samples indicated that no petroleum hydrocarbons were present off site. One soil boring was <br /> advanced on site in the vicinity of the former USTs to evaluate the vertical extent of impacted <br /> groundwater. A groundwater sample collected from the second water-bearing zone indicated that <br /> no petroleum hydrocarbons were present. Results are summarized in ATC's Summary Report of <br /> Supplemental Subsurface Investigation, dated January 4, 2002. <br /> WORKPLAN FOR GROUNDWATER EXTRACTION PILOT TEST <br /> Obiectives and Scone of Work <br /> ATC proposes to perform a 48-hour, low-rate pump test from monitoring well MW 1 (Figure <br /> 2). The objective of the pump test is to determine whether or not groundwater extraction will <br /> lower the concentrations of petroleum hydrocarbon constituents to acceptable levels over a <br /> reasonable time period. <br /> 48-Hour Groundwater Extraction Test <br /> ATC will notify PHS/EHD at least 48 hours prior to performing any fieldwork. Prior to <br /> beginning the pump test, ATC personnel will measure depth to water in all on-site wells and <br /> W A1498 MEPORTMPPUMP.DOC 2 <br />