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i <br /> I <br /> L(:VYATC <br /> A S S O C I A T E S I N C <br /> L with a check valve attached to one end was inserted down the casing until it was immersed in <br /> I <br /> r groundwater. Water was then pumped through the tubing and to the ground surface by <br /> L oscillating the tubing up and down. Groundwater samples were placed on ice and delivered under <br /> chain-of-custody documentation to State-certified AEN laboratory for chemical analysis. <br /> Following soil and groundwater sample collection, the borings were backfilled with neat cement <br /> grout to the ground surface. <br /> L2_4 Soil and Groundwater Sample Analysis <br /> i <br /> j Selected soil and groundwater samples were analyzed by AEN for total petroleum hydrocarbons <br /> L as gasoline (TPHg), benzene, toluene, ethylbenzene, xylenes (BTEX), oxygenate fuel additives, <br /> and total lead. The analytical results for soil samples are summarized in Table 1 and the analytical <br /> Lresults for groundwater samples are summarized in Table 2. Laboratory data sheets and chain=of- <br /> custody documentation are included in Appendix C. <br /> 3.0 SUBSURFACE CONDITIONS <br /> Soils encountered beneath the site consist primarily of silts and sands to a depth of approximately <br /> 31 feet below grade, the maximum depth explored. From the surface to approximately 11 to 14 <br /> feet bgs, soil consists of poorly graded sand with silt. From 11 to 14 feet bgs to 31 feet bgs, the <br /> maximum depth explored, soil consists of silts and sands. A clayey sand layer was encountered in <br /> boring SB 1 between 26 to 29 feet bgs and 31 feet bgs. <br /> Groundwater beneath the site was encountered at approximately 30 feet below grade. Based on <br /> the San Joaquin County Flood Control and Water District, Spring 1995 report, groundwater <br /> L flows to the northeast. <br /> 4.0 RESULTS <br /> r 4_1 Soil Contamination <br /> L <br /> Results of laboratory analyses performed on selected soil samples indicate that petroleum <br /> hydrocarbons are present in the soil beneath the site. Soil samples S131-30.0, S132-20.0, S132- <br /> L 25.0, and SB2-30.0 contained detectable concentrations of toluene, ethylbenzene, xylenes, and <br /> TPHg. Soil sample SBI-25.0 contained detectable concentrations of xylenes and TPHg, and soil <br /> Lsample SBI-20.0 contained detectable concentrations of xylenes. None of the soil samples <br /> contained detectable concentrations of benzene. In addition, none of the soil samples contained <br /> L <br /> w:\14981\14981\reports\psi.doc 3 <br /> L <br />