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, <br /> WEISS ASSOCIATES <br /> Soil samples were collected in steam-cleaned brass tubes with a split barrel sampler <br /> After removal from the sampler, the samples were immediately trimmed, capped with <br /> aluminum foil and plastic end caps, hermetically scaled with duct tape, and labeled and <br /> refrigerated for delivery to Clayton Environmental Consultants, Inc of Pleasanton,California <br /> (CEC) Chain-of-custody forms are presented as Appendix B <br /> WA field classification of the subsurface materials indicated low permeability silty <br /> clays and clayey silts to a depth of about 10 and 15 ft beneath Tanks 1 and 5, respectively <br /> Beneath Tank 6, silty clay extended from ground surface to about 9 ft depth and silty sand <br /> occurred beneath the silty clay to the bottom of the borings at about 10 ft depth Sand that <br /> is interpreted as fill material was encountered beneath Tanks 7 and 8 to a depth of about 7 5 <br /> ft Native clays, silts, and sands occurred beneath this backfill Ground water was not <br /> encountered in any of the borings The historic static ground water levels in the four <br /> municipal wells adjacent to the site (Figure 2) suggest that the ground water depth at the site <br /> is probably 50 to 60 ft <br /> Although no propylene or ethylene glycol was detected in analyzed soil samples from <br /> Tank 5,chemical odors and soil discoloration were noted in the samples collected from borings <br /> beneath Tanks 1, 5 and 6 No odors or discoloration were noted beneath Tanks 7 and 8 <br /> To qualitatively determine the volatile organic compound (VOC) concentration in the <br /> soil samples and to monitor VOCs in ambient air in the vicinity of the drill rig, soil samples <br /> from beneath Tanks 1, 5 and 6 and ambient air were surveyed in the field using the OVA <br /> The OVA, which measures in parts per million by volume (ppmv), is used for qualitative <br /> assessment because the correlation between volume measurement of the instrument and the <br /> weight measurement of the analytical laboratory is not well defined, and because sample <br /> handling procedures in the field are less rigorous than in the laboratory OVA readings for <br /> the soil samples from beneath Tanks 1, 5 and 6 are included on the boring logs in Appendix <br /> A <br /> 2 2 ANALYTIC RESULTS <br /> Analytic results for the soil samples are presented in Tables i and 2 and the analytic <br /> reports are included as Appendix C The sample depths indicated on the tables are depth <br /> below ground surface The soil samples collected beneath Tanks 1, 5 and 6 were analyzed by <br />. modified EPA Method 8015, gas chromatography/flame ionization detection (GC/FID) using <br /> a "DB Wax" megabore-type chromatographic column Ethylene glycol was the calibration <br /> standard, with a method detection limit of 2 parts per million (ppm) <br /> F \ALL\331DWC\331L1FE9 WP P1ge G <br />