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PRIVAED & CONFIDENTIAL TPH in Groundwater The groundwater sample collected from Boring B5 was reported to contain 13 milligrams/liter (mg/1) of TPH-g. The samples collected from MW-2 and MW-4 were reported to contain TPH-g at ' concentrations of 8.4 and 3.8 mg/1, respectively. The samples collected from MW-1 and MW-3 were reported not to contain detectable concentrations of TPH-g. The laboratory results are summarized in Table 3, attached. Laboratory reports and chain-of-custody forms are included as Appendix C. BTEX in Groundwater ' The groundwater sample collected from Boring B5 was reported to contain 0.002 mg/1 of benzene, and insignificant or low concentrations of toluene, ethylbenzene and xylenes. No detectable concentrations of fuel oxygenates were reported in the sample. ' Only the sample collected from MW-4 was reported to contain detectable concentrations of benzene, at 0.008 mg/1. Samples collected from MW-2 and MW-4 were reported to contain insignificant or low concentrations of toluene, ethylbenzene and xylenes. Samples collected from MW-1 and MW-3 were reported not to contain detectable concentrations of BTEX. All groundwater samples were reported as not containing detectable concentrations of fuel oxygenates. The laboratory results are summarized in Table 3. Laboratory reports and chain-of-custody forms are included as Appendix C. Soil Analyses Selected soil samples from what appeared to be distinctive lithologies were collected and analyzed for moisture content, bulk density, effective porosity, total organic carbon content, permeability and particle grain size using ASTM standards. The results of these analyses are summarized in Table 4, attached. The laboratory reports and chain-of-custody forms are included as Appendix C. HISTORICAL DISCUSSION A review of a historic photograph, circa 1950, supplied by the Bank of Stockton Archives and a 1950 Sanborn Fire Insurance Map, revealed that the southeast corner of the subject property was occupied by a Golden Eagle gasoline service station. The gasoline service 1 station consisted of a small building and one pump island. The pump island was located to the east of the small building and consisted of two pump dispensers- Based on the general layout of the former gasoline service station, the location of the pump dispeners and the current concentrations of TPH-g and benzene in the soil, it is Building Analytics' opinion that the underground storage tanks (USTs) for the former service station were located near the southeast corner of the property. More specifically, the USTs would have been located east of the former pump island close to the corner of East Market Street and South Wilson Way, which is beneath the current bank building. Based on previous 8 198075-WFB.Stockton Ph.11 and Quart.Groundwater