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Groundwater Elevation/Flow Groundwater flow beneath the site was unable to be determined due to the presence of only one monitoring well on site. The depth to water in MW 1 taken of May 24, 1995 was 45.83 ft below the top-of-casing. Groundwater flow in the vicinity of the site is generally to the northeast (away from the Stockton Channel and toward a large depression caused by-groundwater extraction in northeast Stockton) as determined from other sites in the area. RESULTS Soil Description The soils beneath the site consisted of intercalated layers of unconsolidated material, consisting predominantly of silt and elastic silt below a depth of 8 ft. An interval of well graded sand was present in each boring between the approximate depths of 26 ft and 31 ft. Discontinuous lenses of clay and silty sand were also noted in some of the borings. Analytical Results of Soil Samples The soil samples collected from soil boring SB 1 did not contain detectable concentrations of TPHg, BTEX, or Oil and Grease, with the exception of the 25.5 ft sample which contained total xylenes at a concentration of 0:010 ppm. Total lead was detected in all of the samples at concentrations ranging from 6 to 10 ppm. The .soil samples collected from soil borings SB2 and SB3 did not contain detectable concentrations of TPHg, BTEX, or Oil and Grease. Total lead was detected in all of the samples at concentrations ranging from 6 to 9 ppm. The soil samples collected from soil boring MW 1 (located in the center of the former UST pit) contained TPHg concentrations of 8,000 ppm and 8,800 ppm in the 20.5 ft and 30.5 ft samples, respectively. Benzene was not detected in any of the soil samples. Toluene was detected at a concentration of 0.011 ppm in the 10.5 ft sample and .007 ppm in the 3 5.5 ft sample. Ethylbenzene was detected at concentrations of 43 ppm and 46 ppm in the 20.5 ft and 30.5 ft samples, respectively. Total xylenes were detected at concentrations of 0.01 ppm, 150 ppm, 210 ppm, and 0.01 ppm, in the 10.5 ft, 20.5 ft, 30.5 ft, and 35.5 ft samples, respectively. Oil and Grease concentrations were detected at concentrations of 230 ppm, 140 ppm, and 50 ppm in the 10.5 ft, 20.5 ft, and 30.5 ft samples, respectively. Total Lead concentrations were detected in all of the soil samples collected from boring MW1 at concentrations ranging from 8 ppm to 61 ppm. Results of the laboratory analyses of the soil samples collected in May 1995 are summarized in Table i Analytical Results: Soil Samples, and shown on Figure 3. • 9