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Clayton ENVIRONMENTAL CONSULTANTS Mr, Robert Wooton Page 8 Stockton Savings Bank Clayton Project No. 70448.00 August 30, 1996 near the three USTs located onsite; no TPH or BTEX have been detected in samples collected from this well. In July 1992, approximately 300 cubic yards of soil was excavated from this site.. Soil contamination was identified underlying the sidewalk and building onsite in November 1993. Three USTs storing diesel fuel and gasoline were removed in December 1993. Soil samples were collected and analyzed; as much as 2,000 mg/kg TPH-G, 15 mg/kg toluene, 37 mg/kg ethylbenzene, and 220 mglkg xylenes were detected in the soil samples. The contaminated soil was excavated; confirmation soil samples were collected from the excavation, and no TPH or BTEX were detected. Confirmation soil borings were drilled in March 1994, and no detectable levels of TPH or BTEX were identified. It appears that the contamination has not impacted the groundwater. Based on the location of the site, the groundwater flow directions identified at nearby sites, and the apparent magnitude of the contamination, we do not expect this site to impact the subject property. • Greyhound, 121 South Center Street This site is located approximately 900 feet southwest of the subject property and is listed on the LUST, Cortese, and UST/AST databases. A UST storing diesel fuel was removed in May 1991. Soil samples were collected from under the UST and piping; as much as 11,000 parts per million (ppm) TPH-D, 0.05 ppm benzene, 0.02 ppm toluene, 0.43 ppm ethylbenzene, and 1 ppm xylenes were detected. According to an April 1996 quarterly report, soil contamination has extended offsite to the west, and the extent of the soil contamination has not been defined. There is approximately 6,000 cubic yards of contaminated soil onsite. The groundwater in three onsite wells was sampled, and no TPH or BTEX were detected. Maximum concentrations of 130 µglL TPH-D, 0.7 og/L benzene, 0.5 ag/L toluene, 0.5 gg./L ethylbenzene, and 1.6 µglL xylenes have been detected historically in the groundwater samples collected onsite. The groundwater flow direction was determined to be easterly. Based on the groundwater flow direction and the location of this site, we do not expect this site to impact the subject property. • Chevron, 139 South Center Street This site is located approximately 900 feet southwest of the subject property and is listed on the LUST, Cortese, and UST/AST databases. A December 1995 quarterly monitoring report stated that up to 300 µglL TPH-G, 36 µglL benzene, and 1.2 pg/L toluene were present in the groundwater samples collected from onsite monitoring wells. The groundwater flow direction was determined to be southeast. Based on the groundwater flow direction and the location of this site, we do not expect this site to impact the subject property. The files for the remaining requested sites were not available for review; potentially, the releases at the Canlis Building and the San Joaquin County OES could impact the ' subject property, based on their locations (less than approximately 150 feet west to K:IEMRT70448%70448R00.232 1