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6.3 Depth to Groundwater, Gradient and Flow Direction The static groundwater level was encountered in the monitoring wells at a depth of approximately 27 to 28 feet bgs. The groundwater gradient was calculated as 0.009 foot per foot and the flow direction is to the southeast. 6.4 Soil Analytical Results ' The laboratory analytical results conducted by Centrum indicate that TPH as motor oil (quantitated as diesel) was detected in borings 133 and 136 at concentrations of 57 mg/kg at 10 feet bgs and 880 mg/kg at 5 feet bgs, ' respectively. TPH as diesel was also detected in boring 136 at 5 feet bgs at a concentration of 1,400 mg/kg. A trace concentration of TPH as gasoline was detected at 2.0 mg/kg in soil at 5 feet bgs in monotring well MW2 and at 5.3 mg/kg in boring 136. Trace levels of VOCs not related to gasoline or diesel were detected in borings 131 (at 20 feet bgs), 136 (at 5 feet bgs) and in MW2 (at 5 feet bgs). These VOCs, other than TCE, are currently unregulated. 6.5 Groundwater Analytical Results ' The laboratory analytical results conducted by Centrum on the groundwater samples indicate the presence of TPH as gasoline (0.7µg11) in monitoring well MW2, TPH as diesel (0.7µg/l) in monitoring well MW3 and benzene in monitoring wells MW 1 and MW2 at 15 µg/l and 1.6 µg/l, respectively. Other VOCs not related to gasoline or diesel were detected in wells MW 1 and MW2 are at insignificant levels. TPH as gasoline was not detected in the groundwater in boring 133 and in monitoring well MWL 7.0 SOIL CUTTINGS AND PURGE WATERS Soil cuttings generated from drilling the borings for the monitoring well decors water and purge water from development of the wells, were placed in 55-gallon DOT-approved steel drums. The drums were stored in a locked storage bin located in the parking lot of the subject property. The soil and water drums were collected, transported and ' disposed as non-hazardous waste by Industrial Waste Utilization Inc. (IWU) of Ontario, California. 8.0 FINDINGS The results of the Phase II investigation indicate the following: ' • The geophysical survey did not detect any evidence of USTs and cleared the boring locations from underground utilities and other detectable interferences. ' • The soils encountered beneath the subject property consist of fine-grained s CRC Environmental Risk Management,Inc. Project#2100-250-2 American Savings Bank 222 North EI Dorado Street November 3. 1995 Stockton,California 12