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This boring was performed through a concrete pad which is part of the cattle corral located adjacent to the site. Boring B-9 was terminated at 6 feet because the dense soils prevented further advancement of the sampling device. Materials encountered during the drilling were described on a boring log by a PG&E geologist. This description included soil classification (Unified Soil Classification System, ASTM D-2487-83), color, moisture content and consistency (in relative terms), and estimated degree of hydrocarbon content (PID measurements). Logs of the borings are presented in Appendix A. Selected soil samples from each borehole were submitted to a State of California -certified analytical laboratory (Chromalab, San Ramon) on November 25 and December 1 and 4, 1992 for chemical analyses. The soil samples were analyzed for total petroleum hydrocarbons as gasoline (TPH-G) by EPA Method 5030/8015, total petroleum hydrocarbons as diesel, kerosene and motor oil (TPH-D, TPH-K and TPH-MO) by EPA Method 3550/8015, total oil and grease by Standard Method 5520 E&F, and benzene, toluene, ethylbenzene and xylenes (BTEX) by EPA Method 8020. BOREHOLE ABANDONMENT On November 30, 1992, at the conclusion of the drilling and sampling activities, the boreholes were backfilled to the surface with a neat cement grout containing about 5% powdered bentonite. The grout was tremied into the bottom of each borehole to prevent the possibility of bridging. The upper few inches of each borehole were backfilled with 3/4 -inch gravel to match the surface of the facility. Borehole abandonment was witnessed by a representative of SJCPHSD. COLLECTION OF WATER SAMPLE FROM NEARBY WATER SUPPLY WELL On April 27th and June 18th, 1993, water samples were collected from the water supply well (Hofinan Well No. 5) located approximately 200 feet east of the facility (Figure 6). On April 27th, the sample was collected downstream of the pressure tank at a discharge point located in the cattle trough where water is constantly purged from the tank. A water sample could not be collected upstream of the pressure tank because the submersible pump did not cycle on to fill the pressure tank. On June 18th, water samples were collected both upstream and downstream of the pressure tank. All water samples collected from this well were submitted to a State of California -certified analytical laboratory (Chromalab, San Ramon) for chemical analyses. The samples were analyzed for total petroleum hydrocarbons as gasoline (TPH-G) by EPA Method 5030/8015, total extractable hydrocarbons (TPH-D, TPH-K and TPH-MO) by EPA Method 3510/8015, and benzene, toluene, ethylbenzene, and xylenes (BTEX) by EPA Method 602. ' cca08/19/93(9660a.doc/cp43) 5-3