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Woodward-Clyde V during the advancement of B-7. Advancement of B-7 from 66 to 100 feet bgs was conducted V to assess the depth to groundwater below the site. Groundwater was encountered in B-7 at a depth of 76.5 feet bgs after retracting the advanced probe rods from 100 to 82 feet bgs. V One grab groundwater sample (MW-7) was collected from soil boring B-7. Sample MW-7 was collected by lowering new clean Teflon tubing equipped with a bottom check valve down the bore of the probe rod. The inner tubing was then oscillated to produce a momentum pumping action. The groundwater sample was placed in laboratory prepared sample containers. The containers were labeled with sample number, date, time, project number, then placed on ice in an ice chest until transported under chain of custody procedures to V California Laboratory Services in Rancho Cordova, California, a certified analytical laboratory. Sample MW-7 was analyzed for TPH as diesel and TPH as gasoline using `r modified EPA Method 8015, and BTEX using EPA Method 8020. The analytical results of groundwater sample MW-7 is presented in Table 3. Based on the analytical results from boring B-3 and the method of backfilling the former UST excavation (photographs 11 and 12 WCFS, 1994), SJCEHD approved the overdrilling of B-3 and additional sampling to assess the vertical extent of soil contamination below the site near the north end of the former UST excavation. 2.1.3 Hollow Stem Auger Soil Sampling On June 22, 1995, WCFS directed the overdrilling of boring B-3 and collection of additional soil samples below the former north end of the UST excavation. Soil boring B-3A was drilled to a depth of 50 feet bgs to evaluate the vertical extent of petroleum hydrocarbons in soil below the former UST. Soil boring B-3A was backfilled upon completion to approximately 12 feet bgs with a neat cement plus bentonite grout mixture. The top 12 feet of B-3A remains open. The borehole is plugged with a plastic 5-gallon bucket for safety precautions. V Soil samples were collected from boring B-3A using a two-inch diameter split spoon sampler with brass liners by the following method. After the augers were advanced to the desired V depth, the drilling assembly, consisting of an end plug attached to drill rod, was removed from the center of the hollow stem augers. The sampling assembly consisting of the split V 8054/FEMAWAXPIER.RPr/8-24-95 SAC 2-6 V