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EXECUTIVE SUMMARY <br /> Upgradient Environmental Consultants visited the Valley Motors dealership on June 5 to measure <br /> water depths and collect groundwater samples from the four on-site monitoring wells The depth to <br /> groundwater is essentially unchanged since March, and the static water level is at an average depth <br /> of 30 25 feet below grade The depth data were converted to elevations and contoured to produce a <br /> hydraulic gradient map, and the gradient is somewhat different from that seen in previous quarters <br /> Rather than trending essentially north-south and indicating eastward groundwater flow, the contours <br /> imply a slight north-south trending depression in the piezometric surface,producing an overall <br /> southward groundwater flow direction P i <br /> After the depth to groundwater was measured, the wells were purged and then sampled by lowering <br /> a disposable Teflon® bailer below the static water level The samples were poured into 40-m1 vials <br /> and preserved for laboratory analysis Four samples were collected and analyzed for TPH-gasoline <br /> using EPA method 8015m and for BTEX using EPA method 8020 <br /> Hydrocarbon concentrations in all wells were sharply higher from the previous quarter This is <br /> particularly true of VM-1, where all BTEX compounds reached new maximums In addition, the <br /> benzene concentration of 21 parts per billion is a new high in VM-3 These increases could riot be <br /> due to fluctuations in the water table, because the depth to groundwater has risen only a few inches <br /> since March The most likely explanation is that purging a larger volume of water allowed more <br /> contaminated water to flow in from the formation <br /> • <br /> 1 <br />