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KLEINFELDER 3 FIELD ACTIVITIES On December 18, 1990, two vertical borings were drilled at the site using a truck-mounted drill rig equipped with 6-inch hollow stem flight augers. The approximate locations of the borings are shown on Plate 2. Both borings were drilled to a total depth of 15 feet, and sampled to 16.5 feet. The soil was generally sand overlain by clayey sand from approximately 12 feet to surface. Although the soil was moist, ground water was not encountered in either of the borings. The borings were abandoned to surface with a bentonite/cement grout inplaced by tremie. A boring log legend, and the boring logs are contained in Appendix B. Soil samples were collected at 5-foot intervals to the bottom of each boring. Samples were collected by advancing the boring to a point immediately above the sampling depth and then driving a Modified California Sampler lined with three brass tubes into the undisturbed soil. The sampler was then removed from the bottom of the boring, and the bottom (third) tube sealed with Teflon sheets and tight fitting plastic caps, labeled and logged on a chain-of-custody, and immediately stored in an iced cooler for transportation to California Analytical Laboratories/Enseco. A PID was used to provide a qualitative screening of the samples. The organic vapor analyzer monitors total ionizable compounds (with electron volt excitation less than 10.6 eV) in the air in parts per million by volume (ppmv) in relation to a calibration standard. PID readings ranged from 0.0 to 0.3 ppmv for the samples collected from the borings. To reduce the potential for cross-contamination, augers and associated equipment were steam cleaned prior to drilling each borehole. The sampling equipment was cleaned with a trisodium phosphate wash and distilled water rinse prior to collecting each soil sample. Drill cuttings were placed in 55-gallon drums. F17-91-11 3 Copyright 1991 KLeinfelder, Inc.