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s [a jvly 1990: Based on the results of the in-situ sampling, = approximately 3,060 cubic yards of soil were excavated and transported to the Class III Durham Road Landfill in Fremont, California, for disposal. Approximately 3,020 cubic yards of soil were excavated and transported to the Liquid Waste Management, Inc. Class II facility in McKittrick, California. The excavation was backfilled with clean, imported fill. September, 1990: Four soil borings were drilled onsite and subsequently converted into 4-inch-diameter monitoring wells, AW-1, AW-2, AW-3, and AW-4, all with total depths of 25 feet below grade. No TPH--G, TPH-D, BTEX, or organic lend wan detected above method detection limits in any of the soil samples selected for analysis from the four borings (see Table 1). Of the four ground water samples, only --.-he sample from AW-3 had detectable concentrations of TPH-G, TPH-D, and BTEX constituents (see Table 2) . April/May 1991: Nine soil borings were drilled on and offsite. During drilling, discrete soil samples were collected and screened in the field using a combustible gas j indicator (CGI) . A temporary, 2-inch-diameter, perforated polyvinyl chloride (PVC) casing with 0.020--inch slots was then installed in each of the boreholes. The temporary wells were purged and sampled. soil Borings B-4, B-2, B-3, and B-9 were converted to ground water Monitoring Wells AW-5, AW-6, AY7-7, and AW-8, respectively. The wells were completed to a depth of 25 feet below grade using 4-inch-diameter PVC ! .' casing. The new wells were sampled on May 6, 1991. The highest concentrations of TPH-G, TPH-D, and BTEX constituents were detected in the water samples collected from B-6 and B-7, bath of which were located onsite and downr�radient of the former tank area. See Tables 1 and 2 for complete soil E and ground water samples analyses results. �1 i i.m