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f and total xylenes were present in a groundwater sample acquired from monitoring well MW-2 . .. . one of three on-site groundwater monitoring wells . .The an results reported by AES appear in Table 2 . ' Detectable concentrations of fuel hydrocarbons were also present in soil samples acquired during the installation of monitoring wells MW-1 and MW73 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 w-ere 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 Cali1 ornia- 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, and placed in an iced, insulated container for trans- portation to JL Analytical Services under chain of custody . Subsequent analyses were performed for Total Petroleum Page 2