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i Petroleum Hydrocarbons y (TnH) , less than 0.5 parts per ma.11ion (ppm) . Monitor well MW-3 was also found to be below detection likaits for the Volatile Aromatic Compounds of Benzene, Toluene, Ethylbenzene, and Xylenes (BTEX) . Monitor wells MW-1 and MW-4 are above the drinking water action levels for benzene (1 ppb as stated in the LUFT manual revision 10/18/83) at 16 pp, and 6.7 ppb respectively. only water sampled from MW-2 showed above detectable levels for all of the BTEX compounds, although none were above the action levesl set by the LUFT manual for drinking water, see TABLE 3 and APPENDIX B. SOIL CONTAMINATION As stated earlier five additional sample borings were performed on January 23 thru 25, 1990. These borings delineated the contaminated soil associated with the pump island and the tank excavation, SEE FIGURE 3 and APPENDIX A. Soil contamination, gasoline range hydrocarbons, exists to 15 feet below the surface beneath the easvern and center pump dispensing islands. Soil contamination associated with the tank excavation is gasoline range hydrocarbons to the 30 foot depth, ground waver is encountered at approximately 47 feet below the surface, see FIGURES 6A-1 and 6A-301-1, TABLE 1 and APPENDIX B. SOIL AND GROUND WATER SAMPLING PROCEDURES All samples were obtained by a qualified geologist working •>� directly under the supervision of California Registered Geologist #3037. The samples were collected, preserved, labeled and chain of custody hand delivered to ChemTech Analyt?cal Laboratories, 3017 Kilgore Road #110, Rancho Cordova, CA 957442 (916-635-3952) . ChemTech is a State of California certified lab (#359) . All samples obtained from the borings and monitor wells were analyzed using the following EPA and DOHS methods; 5030 for extraction, 8015-TPH, and 8020/602-BTEX. Since initial sampling showed that TEL and EDB did not exist at this site these analyses were not carried on for this sampling. Prior to obtaning a ground water sample from a monitor well, a water interface probe is lowered i.n,.o each well to obtain a depth to ground water measurement. Then the wells were purged (approximately 15 gallons) until temperature, pH, and conductivity stabilized, indicating that fresh ground water would be sampled. A dedicated sterile disposable PVC bailer is then lowered into the well to collect the ground water szmple. The ground water is then slowly decanted into EPA series 200 clean glass sample containers (1-one liter boston round and 4-40 ml VOA vials per well) . The sample containers are then labeled (site designs ion, well number, date, time sampled and analysis) , sealed in zip lock baggies, placed in an cooler with ice and cooled to 46C. The samples are then chain of custody, hand delivered to the laboratory performing the analysis. 2