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. EXECUTIVE SUMMARY Upgradient Environmental Consultants visited the Valley Motors dealership on rune 6 to measure water depths and collect groundwater samples The static water level has changed very little since December 2001,and has fallen only about 4 inches in the past 6 months It remains at about 33 feet below grade Depth measurements indicate that groundwater currently flows to the east-northeast Historically,the flow direction has vaned from northeast to southeast After the depth to groundwater was measured, the four monitoring wells were purged of standing water and sampled with disposable Teflon® bailers The samples were poured into 40-m1 vials and transported to Excelchem Environmental Laboratory,where they were analyzed for TPH-gasoline using EPA method 8015m, for BTEX using EPA method 8020, and for gasoline oxygenates using EPA method 8260 Hydrocarbon concentrations in three of the four wells were nearly identical to those that were detected in the first quarter of the year, Concentrations declined slightly (20-50%) in the fourth well (VM-4) The last time that concentrations remained this stable was in late 1996-early 1997 No gasoline oxygenates were detected in any samples, and the results are in accord with the data from previous samples The data have consistently supported our conclusion that oxygenates are not a significant contaminant in the groundwater This offers strong evidence that the unauthorized release took place before oxygenates came into widespread use in the early 1990's • TPH-g concentrations were contoured to develop a preliminary map of the gasoline plume The - four data points, supplemented by older data from hydropunch borings and vapor extraction and air spargmg well samples, suggests that the plume is elongate in a northwest-southeast direction and covers about one-fourth of an acre The maximum TPH-g concentration in the center of the plume (between SW-1 and VM-2) is between 60,000 and 7000 parts per billion To date,the highest recorded TPH-g concentration is 110,000 ppb in SW-I in March 2000,but after that initial sampling the concentration in that well dropped below 60,000 ppb i1