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. feet, and 55 feet respectively. Groundwater monitoring wells MW-1, MW-2 , and MW-3 were constructed in borings B-2 , B-3 , and B-4 respectively. Generally the soil encountered beneath the site consisted of clays in the upper 5 feet, interbedded sandy clays and silty clays from approximately 5 to 30 feet bgs, sands from approximately 30 to 38 feet bgs, clays from approximately 39 to 47 feet bgs. Silty sands from approximately 47 to 52 feet bgs, and clays from 50 feet to the bottom of the Kleinfelder borings (approximately 60 feet bgs) . Kleinfelder collected a total of twelve (12) soil samples from the four soil borings. Additionally, three (3) groundwater samples were obtained from monitoring wells installed within 3 of the 4 borings. Petroleum hydrocarbons were detected in all twelve (12) of the soil samples analyzed. However, only trace concentrations were present in the samples analyzed from the boring associated with Monitoring Well MW-3 (aka Boring B-4) . The hydrocarbons noted in all of the soil samples analyzed can be generalized as primarily volatiles in the gasoline range with a high percentage of benzene, toluene, ethylbenzene, and xylenes (BTEX) . Only minor concentrations of the heavier hydrocarbons (greater than C16 range) were present. The compounds and concentrations present are indicative of a gasoline. All of the groundwater samples obtained were analyzed for the presence and concentration of benzene, toluene, ethylbenzene, total xylenes (BTEX) , total petroleum hydrocarbons as referenced to • gasoline (TPH-G) , total petroleum hydrocarbons as referenced to kerosene (TPH-K) , and total recoverable petroleum hydrocarbon (TRPH) . All three groundwater samples revealed concentrations of benzene above the Maximum Contaminant Level. The samples obtained from MW-1 & MW-2 revealed toluene, ethylbenzene, and total xylenes above the California EPA Action Level. High concentrations of TPH-K, TPH-G, and TRPH were also present in the samples obtained from wells MW-1 and MW-2 . Although well MW-3 contained only trace amounts of contamination during the December 1994 quarterly monitoring, the March 1995 quarterly monitoring revealed that well MW-3 tested above acceptable limits for Ethyl Benzene, Toluene, Xylenes and gasoline. As a consequence of the results obtained from Messr. Sasson of the San Joaquin County Public Health Services Department Environmental Health Division, further assessment of the extent of hydrocarbons in groundwater are needed. •