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understanding from Mr Ken Gillies that the well was sampled periodically thereafter and that no • groundwater contamination was detected, but Upgradient has not examined any additional laboratory reports Upgradient was retained in August, 1994 and supervised GT 1 (Figureinstallation 2} were selectedofor ' monitoring wells in September Five soil samples laboratory analysis, and all five contained both diesel and gasoline-range hydrocarbons Total Petroleum Hydrocarbon (TPH) concentrations decreased downward from 7050 mg/kg at 35 feet to 104 mg/kg at 55 feet Three samples were selected from GT-2 for analysis A TPH concentration of 288 mg/kg was reported at a depth of 55 feet, no contamination was detected at 50 feet or 60 feet Diesel was detected in the groundwater sample from both wells, and gasoline was also detected in the sample from GT-2 No hydrocarbons were detected in the groundwater sample from MW-1 Groundwater elevations measured in September did not provide conclusive evidence regarding the direction of groundwater flow, but suggested flow to the northwest Data previously published by the San Joaquin County Public Works Department had indicated red the depprevailing to flow direction was to the south or southwest Therefore, Upgradient measu groundwater in both November and December to obtain additional information on flow direction As reported in the Fourth Quarter 1994 Report, groundwater data obtained d in January land July 1995 equal, but suggested groundwater flow to the so ls were nearly ut also suggested a southward groundwater flow ii direction aThe in the January increase as in g oundwater concentrations in groundwater was correlated encountered the contaminated soil above I depth of 75 feet Groundwater continued to rise during the early summer, and by July had risen more than heeefon dw �r sample d ollec ed in Joall ly wells Not surprisingly, no contaminants were detecte g Upgradient performed the third quarter 1995 monitoring in Septermber At that time, groundwater was still several feet above the screened interval in both GT-1 and MW-1, and neither well was sampled GT-2 could not be located, ocamap was prepared having been buried during road grading work since the previous monitoring Therefore, gradient 3.0 MONITORING PROCEDURES The fourth quarter groundwater monitoring took place on December 19, 1995 Upon arrival atre the site, all three wells were located and opened A 5olinst water level meter was used to measure the depth to groundwater, and the data were rded on the above the toptached of the screenell ed intervalonitor Report, and (Appendix A) The water table was still several feet therefore no samples were obtained elevations are presented in Depth-to-groundwater measurements and calculated groundwateincluded forrcomparison The elevation of Table 1 Results from previous monitoring events • 2