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• The soils encountered beneath the subject property consist of fine-grained sediments such as clay, silt, silty sand and sandy silt. The soils below the groundwater table consist mostly of silty, fine grained sand with a few scattered gravels. A wide variation of soil types in the horizontal and vertical directions was observed in the samples. ' • Groundwater was encountered during drilling at depths ranging from 30 to 36 feet bgs. The groudwater level rose in the borings to a piezometric surface at depths ' ranging from 26.5 to 28 feet bgs. • The groundwater table beneath the subject property is at an approximate elevation ' of 15 to 16 feet below mean sea level. The groundwater gradient is 0.009 foot per foot and the flow direction is to the southeast. The groundwater gradient and flow directions are subject to seasonal fluctuations. A report of investigation on ' the former Shell gasoline station to the southwest indicated that the groundwater flow direction was to the east in 1990. ' • The Iaboratory analytical results indicate the presence of TPH as motor oil (57 mg/kg) in boring B3 at 10 feet bgs. TPH as motor oil (880 mg/kg) and TPH as diesel was detected in B6 at 5 feet bgs. • Trace levels of TPH as gasoline were detected in the soil at a depth of 5 feet bgs in soil boring B6 and in monitoring well MW2, at 2.0 mg/kg and 5.3 mg/kg, I'M respectively_ A trace level (0.007 mg/kg) of TCE was detected in the soil in boring B1 at 20 ' feet bgs. Other VOCs not related to gasoline or diesel were detected in boring B6 at 5 feet bgs and in MW2 at 5 feet bgs at low levels ranging from 0.005 to 0.11 mg/kg. These detected VOCs were tert-Butylbenzene, ethylbenzene, }, Isopropylbenzene, p-Isopropyltoluene, n-Propylbenzene, Total Xylene, 1,2,4- Trimethylbenzene, 1,3,5-Trimethylbenzene, n-Butylbenzene and sec- Butylbenzene. These VOCs are currently unregulated. ' • Benzene was not detected in any of the soil samples analyzed on the subject property. Benzene, however, was detected in the groundwater in monitoring ' wells MW 1 and MW2 at concentration levels of 15 µg11 and 1.6 µg/l, respectively. These benzene concentration levels exceed the State Maximum ' Contaminant Level (MCL) of 1.0 µg11 for drinking water. • Other VOCs not related to gasoline or diesel that were detected in groundwater in monitoring wells MW1 and MW2 were sec-Butylbenzene, cis-1,2- ' Dichloroethene, n-Propylbenzene, n-Butylbenzene, n-Propylbenzene, and 1,2,4- Trimethylbenzene. These VOCs were detected at low concentration levels ranging from 0.5 to 3.4 µg/1. Except for cis-1,2-Dichloroethene, the above- mentioned VOCs are currently unregulated. However, the detected levels of cis- CRC Environmental Risk Management,Inc. Project A 2100-250-2 American Savings Bank 222 North El Dorado Street November 3, 1995 Stockton.California 13 1