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. EXECUTWE SUMMARY <br /> Upgradient Environmental Consultants visited the Valley Motors dealership on March 20 to <br /> measure water depths and collect groundwater samples The depth to groundwater has not changed_ <br /> since December 2001, and remains at about 33 feet below grade Depth measurements indicate that <br /> groundwater currently flows to the east-northeast Historically, the flow direction has varied from <br /> northeast to southeast <br /> After the depth to groundwater was measured, the four monitoring wells were purged of <br /> approximately 20 gallons of water and sampld'd with disposable Teflon® bailers The samples were <br /> poured into 40-m1 vials and transported to Excelchem Environmental Laboratory, where they were <br /> analyzed for TPH-gasoline using EPA method 8015m and for BTEX using EPA method 8020 One <br /> sample was also analyzed for gasoline oxygenates using EPA method 8260 <br /> Hydrocarbon concentrations in all wells were higher than those that were detected in the fourth <br /> quarter of 2001 Graphs of TPH-g and total BTEX concentrations over time were prepared for VM- <br /> I and VM-2, and these graphs illustrate that concentrations have fluctuated up and down from <br /> quarter to quarter in both wells In VM-2, the magnitude of these fluctuations has increased over <br /> time, as have the concentrations themselves The TPH-g concentration in this well has exceeded <br /> 50,000 ppb for three consecutive quarters In VM-1,the TPH-g concentration remained between <br /> 1,000 and 2,500 ppb from 1995 to 1998, increased to over 4,000 ppb in Iate 1998, began a long <br /> decline in early 1999, and has now returned to the 1995 level <br /> No gasoline oxygenates were detected in the one sample that was analyzed for these constituents <br /> Of the twenty-nine samples that have been analyzed for oxygenates since December 1997, only <br /> seven have contained detectable concentrations of oxygenates, and all results except one have been <br /> 5 ppb or less It is therefore apparent that oxygenates are not a sigmficant contaminant in the <br /> groundwater, which implies that the unauthorized release took place before oxygenates came into <br /> widespread use in the early 1990's <br /> • 1 <br />