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' Tri-Valley Growers March 24, 1988 Project No. 1582G Page 5 ANAMICAL_RESULTS Water and soil samples collected were transported to an analytical laboratory certified by the State of California,. Department of Health Services (DHS). All water and soil samples were analyzed for total extractable hydrocarbons (TEH), total volatile hydrocarbons (TVH), benzene, toluene, and total xylenes (BTX) and total lead. F•.a Soil from the excavation piles were all belcw-detection-lirnit (BDL) of the laboratory for TVH and TEH. Total lead was found to be 6.8 parts-per-million (ppm) in the composite sample from the southern soil pile and 7.7 ppm in soil from the northern soil pile. { The composite soil sample from exploratory boring MW-4 was found to be BDL for TEH, TVH, and BTX. Total lead was found to be 5.6 ppm in the soil from the boring. in Results of analysis on the water sample from the well adjacent to Tri-Valley Growers revealed no detectable concentrations of TEH, TVH, BTX, and total lead. The water sample from the new monitoring well (MW-4) contained concentrations of 9,108 parts-per-billion (ppb) TVH, 630 ppb Benzene, 120 ppb toluene and 440 ppb total xylenes. TEH were present in the water sample at a concentration of 3,400 ppb. Total lead was quantified slightly above the detection limit at a concentration of 6 ppb. Laboratory reports are attached. DISCUSSIQ The ground-water surface as maasured on February 8, 1988 is presented in Figure 2. The gradient as shown in to the west at an average calculated gradient of 0.0033 feet per foot. This direction is approximately 120 degrees different from that previousiy determined for the site. The most recent data indicates that the local ground-water surface changed significantly over time. The data also indicate that the local ground-water gradient is fairly flat and