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i • • Paye 2 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 . Detectable concentrations of fuel hydrocarbons were also present in soil samples acquired during the installation of monitoring wells 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 ced nine (9) soil borings at the locations shown on figure 2 n order to further define the extent of soil and s allow 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,