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Undisturbed soil samples were collected continuously as drilling <br /> ' progressed for lithologic and hydrogeologic description and for possible <br /> chemical analysis The samples were collected by driving a sampler lined <br /> with acetate tubes using hydraulic direct push methods Selective soil <br /> ' samples were immediately cut, trimmed, sealed with Teflon tape, plastic <br /> end caps and duct tape, labeled, sealed in plastic bags and stored on ice for <br /> transport to Chromalab, Inc of Pleasanton, California (ELAP #1094) under <br /> chain of custody Soil from the remaining tubes was described by the site <br /> geologist using the Unified Soil Classification System and was screened for <br /> volatile compounds using an Organic Vapor Meter (OVM) The soil w a s <br /> ' screened by emptying soil from one of the sample tubes into a plastic bag <br /> The bag was then sealed and placed in the sun for approximately 10 <br /> minutes After the VOCs were allowed to volatilize, the OVM measured the <br /> vapor in the bag through a small hole punched in the bag OVM readings <br /> are used as a screening tool only, since the procedures are not as rigorous <br /> as those used in the laboratory <br /> A temporary PVC well casing was driven into place in each boring for the <br /> ' collection of groundwater samples Groundwater samples were removed <br /> from the borings with pre-cleaned bailers The groundwater samples were <br /> contained in 40-m1 volatile organic analysis (VOA) vials and preserved <br /> with hydrochloric acid Groundwater samples from borings BH-B and BH-E <br /> were also contained in 1-liter amber glass containers for potential analysis <br /> for extractable-range hydrocarbons since it appeared that groundwater <br /> from these borings may have contained heavier range hydrocarbons Each <br /> sample was labeled, placed in protective foam sleeves, and stored on ice <br /> for transport to Chromalab under chain of custody <br /> Drilling equipment was cleaned with a TSP solution between sampling <br /> ' intervals and between borings to prevent potential cross-contamination <br /> 1 Sediments encountered during drilling generally consisted of sandy silt <br /> from the ground surface to the total depth explored of 10 0-feet bgs <br /> Groundwater was encountered at approximately 65-feet bgs and did not <br /> rise in the borings indicating unconfined conditions Boring logs are <br /> presented as Appendix B <br /> 5 . 0 ANALYTICAL RESULTS FOR SOIL <br /> The soil sample collected from 6 5-feet bgs in each boring (the capillary <br /> zone) was analyzed by Chromalab for TPH-G by modified EPA Method <br /> 5030/8015, BTEX by EPA Method 8020, fuel oxygenates by EPA Method <br /> ' 8260, and total lead by EPA Method 6010 The soil analytical results are <br /> 574 West Grant Line Road, Tracy, California - April 1998 <br /> -3- <br />