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WEBS ASSOCw>ES I M( Soil samples were collected in steam-cleaned brass tubes with a split barrel sampler. After removal from the sampler, the samples were immediately trimmed, capped with aluminum foil and plastic end caps, hermetically sealed with duct tape, and labeled and refrigerated for delivery to Clayton Environmental Consultants,Inc.of Pleasanton,California (CEC). Chain-of-custody forms are presented as Appendix B. WA field classification of the subsurface materials indicated low permeability silty clays and clayey silts to a depth of about 10 and 15 ft beneath Tanks I and 5, respectively. Beneath Tank 6, silty clay extended from ground surface to about 9 ft depth and silty sand occurred beneath the silty clay to the bottom of the borings at about 10 ft depth. Sand that is interpreted as fill material was encountered beneath Tanks 7 and 8 to a depth of about 7.5 ft. Native clays, silts, and sands occurred beneath this backfill. Ground water was not encountered in any of the borings. The historic static ground water levels in the four municipal wells adjacent to the site (Figure 2) suggest that the ground water depth at the site is probably 50 to 60 ft. Although no propylene or ethylene glycol was detected in analyzed soil samples from Tank 5,chemical odors and soil discoloration were noted in the samples collected from borings beneath Tanks 1, 5 and 6. No odors or discoloration were noted beneath Tanks 7 and 8. To qualitatively determine the volatile organic compound (VOC) concentration in the soil samples and to monitor VOCs in ambient air in the vicinity of the drill rig,.soil samples from beneath Tanks 1, 5 and 6 and ambient air were surveyed in the field using the OVA. The OVA, which measures in parts per million by volume (ppmv), is used for qualitative assessment because the correlation between volume measurement of the instrument and the weight measurement of the analytical laboratory is not well defined, and because sample handling procedures in the field are less rigorous than in the laboratory. OVA readings for the soil samples from beneath Tanks 1, 5 and 6 are included on the boring logs in Appendix A. 2.2. ANALYTIC RESULTS Analytic results for the soil samples are presented in Tables 1 and 2 and the analytic reports are included as Appendix C. The sample depths indicated on the tables are depth below ground surface. The soil samples collected beneath Tanks 1, 5 and 6 were analyzed by modified EPA Method 8015, gas chromatography/flame ionization detection (GC/FID) using a "DB Wax" megabore-type chromatographic column. Ethylene glycol was the calibration standard, with a method detection limit of 2 parts per million (ppm). F:\ALG\331D W G\331LIFE9.W P Page 6