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i E u s Firastone Titre and Rubber Company Page 2_ Stockton, CA., Soil Sampling Results 10, 1991. The workplan anticipated analysis for total petroleum hydrocarbons (TPH) and benzene, toluene, ethylbenzene and xylene (BTX&E), Diesel F concentrations were reported at minor concentrations in all samples; ranging from 1.3 to 1.7 mg/kg. One sample in Boring 2, at the 15 to 16 foot sample, was reported with minor concentration of xylene at 0.024 mg/kg. All other BTX&E concentrations were reported;below detection limit. Additional soil spmples for PCiBs and soluble lead were also analyzed at the request of the PHS inspector;IHa'rlin Knell The PHS requested the samples to confirm that 1) PCBs are not detected W the site, and 2) the low total lead concentrations summarized in the wo•*plan are not all soluble. As summarized in Table 1, there,were ns detectable PCBs or soluble lead reported above 0.017 mg/kg and 0.8 mel,'respr:rtively. I' Based on the drilling work, field observations by Kleinfelder, and laboratory results reported by Curtis and Tompkins, the chemical distribution at the Tank 6 site appears to be local and;contained within the near surface soils adjacent to _ t the tank. 7%ere appears to be no horizontal migration or distribution to the north and zouth of the tank site.' There also appears to be no vertical migration I based on fie 30 and 40 foot soil sample laboratory results, i After drilling work was completed and soil samples retrieved, the two borings i were sealed with a bentonite/cement grout slurry. Mr. Harlar was present during the sealing work. T At the request of the PHS, the Tank 6 site was resampled to confirm that tI.are have been no releases or migration of gasoline compounds at the site. Additional. soils were excavate_d from the western extent of the tank site to a depth of 16 feet. The location;of the resampling work was based on what the PHS considered marginally high TPH as gasoline (34 mg/kg) reported for the western soil sample in the Work Plan.'i Soil samples were analyzed for TPH as gasoline, c BTX&E, and soluble lead. The soluble lead analysis was requested in the field by t the PHS inspector, Harlin Knoll) To provide a vertical, as well as horizontal profile of potential h; irbons in soils at the Tank 6 site, soil samples were taken at three locations . i at varying depths: bottom of the excavation at 16 feet below grade, and the nor..., and south walls of the excavation at 14 feet;and 12 feet, respectively. Each soil sample was taken by driving a pre-cleaned brass tube into undisturbed soils within the excavation. After the soil samples were taken, each brass tube was sealed with teflon tape, capped, logged, aand placed on ice. All soil samples were reported below detection limits. Based on the laboratory results reported by Curtis and Tompkins there appears to be no hydrocarbon release from the Tank 6 site. s . li f�