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PROBLEM ASSESSMENT REPORT 6131 Pacific Ave , Stockton, CA Aegis Project No 40-020 Page 6 Figure 4 presents generalized cross section A-A' and B-B' . The locations of the cross sections are presented on Figure 3 . As shown on the cross section the subsurface soil conditions are heterogeneous beneath the site. Soil types appear to fluvial in nature. Contacts between the soil types are gradational in nature. 3.2 Boil Sample Analytical Results A total of 15 soil samples recovered from the well borings were submitted for analysis to NET Pacific Laboratory. Soil samples were analyzed for petroleum hydrocarbons volatile (PHV) by EPA method GC FID/5030 and benzene, toluene, ethyl benzene, and xylene (BTEX) by EPA method 8020. The results of the soil samples are summarized in Table 2. The highest concentrations of petroleum hydrocarbons in soil were found in soil boring VE-2 . Three soil samples analyzed from VE-2 contained petroleum hydrocarbons above 1000 parts per million (ppm) . Levels of total petroleum hydrocarbons (PHV) in recovered samples from VE-2 were 2 , 800 ppm, 3 , 700 ppm and 12 , 000 ppm from 25, 40 and 45 feet below grade, respectively. Gasoline odors and PID readings were noted as strong throughout the boring. VE-1 was installed through the previously characterized backfill material in the original tank basin. Subsequently, soil samples were not collected and analyzed from VE-1. Petroleum hydrocarbons were also found in soil samples recovered from 1 MW-1 through MW-3 . Soil sample MW-1J, collected from 50 feet below grade, contained 0. 0042 ppm xylenes. Soil sample MW-2H, collected from 40 feet below grade, contained 0. 0043 ppm toluene and 0. 0059 ppm xylenes. Two soil samples recovered from MW-3 contained petroleum hydrocarbons. Sample MW-3/K, collected from 55 feet below grade, contained 28 ppm 1 PHV and 0. 380 ppm benzene, 0. 790 ppm toluene, 0 . 180 ppm ethyl benzene, and 0 . 990 ppm xylenes. Sample MW-3/M, collected from 65 feet below grade contained, 0 . 0058 ppm benzene, 0. 022 ppm toluene, 0 . 0047 ppm ethyl benzene, and 0 . 24 ppm xylenes.