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indicated that detectable concentrations of Total Petroleum �.� Hydrocarbons as Gasoline (TPH-G) , toluene , ethylbenzene , and total xylenes were present in a groundwater sample acquired from monitoring well MW-2 . . . one of three on-site groundwater monitoring wells . The analytical results reported by AES appear in Table 2 . Detectable concentrations of fuel hydrocarbons were also present in scil samples acquired dur=.ng the installation of monitoring wel ' s MW-1 and MW-3 during July , 1991 , and in other soil samples acquired from the area formerly occupied by the underground gasoline storage tanks during July , 1989 and July, 1990 . Four soil borings were also advanced during during July of 1991 . Soil samples acquired from these borings contained significant levels of fuel hydrocarbons ( including 5 , 100 parts per million {ppm} Total Petroleum Hydrocarbons as Gasoline {TPH-G} and 2 , 000 parts per billion {ppb} benzene in SB1 at 9 feet , and 220 ppm TPH-G in SB2 ) . On September 30 and October 1 , 1993 , Del Tech Geotechnical Support Services of Oakdale advanced nine ( 9) soil borings at the locations shown on Figure 2 in order to further define the extent of soil and shallow groundwater contamination. Each boring was advanced with a hand auger . Discrete soil samples and a grab water sample were acquired from each borehole . Each soil sample was collected within a 1 . 9 inch diameter by 4 . 0 inch long clean brass sleeve fitted within a drive sampler lowered into the borehole to a point accessed by the hand auger . Upon being retrieved, the drive sampler was opened and the brass sleeve removed. The ends of each sleeve were then covered with teflon sheeting/aluminum foil , fitted with plastic caps , and sealed with duct tape . Each tube was then marked and placed in an iced , insulated container for transportation to JL Analytical Services , Inc . of Modesto, a California- state certified hazardous waste analytical laboratory , under chain of custody . Subsequent analyses were performed for Total Petroleum Hydrocarbons as Diesel (TPH-D) , Total Petroleum Hydrocarbons as Gasoline (TPH-G) , benzene, toluene , ethylbenzene , and total xylenes (BTEX) using EPA Methods 3550/8015 and 5030/8015-8020 , respectively; and for Total Oil and Grease (TOG) using SM 5520 D&F. Grab water samples from each boring were acquired within a clean, disposable polyethylene bailer lowered into the bore hole to a point just below the surface of the water . Upon being returned to grade , the contents of each bailer were transferred into four Volatile Organic Analysis (VOA) vials and two amber glass liter bottles . Each container was promptly covered with a teflon-lined screw cap, labeled , Aftwf' and placed in an iced , insulated container for trans- Page 2