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groundwater contamination was detected, but Upgradient has not examined any additional laboratory reports Upgradient was retained in August, 1994 and supervised the installation of two additional monitoring wells in September Five soil samples from GT-1 (Figure 2) were selected for 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-I 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 that the prevailing flow direction was to the south or southwest Therefore, Upgradient measured the depth to groundwater in both November and December to obtain additional information on flow direction As reported in the 4th Quarter Report, groundwater elevations in all wells were nearly equal, but suggested groundwater flow to the south The data obtained in January and July 1995 also suggested a southward groundwater flow direction The January increase in gasoline concentrations in groundwater was correlated with a rise in the water table, as groundwater encountered the contaminated soil above a depth of 75 feet Groundwater continued to rise during the early summer, and by July had risen more than 8 feet above the screened interval in all wells Not surprisingly, no contaminants were detected in the groundwater samples collected in July 3.0 MONITORING PROCEDURES Groundwater monitoring took place on September 16, 1995 Upon arrival at the site, Upgradient personnel noted that GT-1 and GT-2 had again been buried during grading operations that had taken place since the July monitoring event After several minutes of digging and poking, GTA was uncovered However, GT-2 could not be located A Solinst water level meter was used to measure the depth to groundwater in MW-I and GT-1 The data were recorded on the attached Well Monitor Report The data indicated that the water table is still several feet above the top of the screened mterval, and therefore no samples were obtained In accordance with the recommendation of Mr Steve Sasson of PHS/EHD in his August 1995 letter to Gillies Trucking, samples will be collected when the water Ievel drops below the top of the screen This will probably not occur during the remainder of 1995 Depth-to-groundwater measurements and calculated groundwater elevations are presented in Table I Results from previous monitonng events are included for comparison •