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LM <br /> CV\/AT4L <br /> &,,, A S S O C I A T E S I N C . <br /> grouted the top five inches of the boring with a bentonite grout mixture as a temporary measure <br /> ` to prevent tampering with the boring until the storm drain is repaired. At that time, ATC will <br /> properly grout the boring to the surface. <br /> 2_2 Sample Analysis <br /> Selected soil samples from borings SBI, SB2, and SB3 and the grab groundwater sample from <br /> boring SBI were placed on ice, and transported under chain-of-custody to Sequoia Analytical <br /> (FLAP No.1271) of Walnut Creek, California for analysis. All soil samples were analyzed for <br /> LM total petroleum hydrocarbons as diesel (TPHd), and benzene, toluene, ethylbenzene, and xylenes <br /> (BTEX) utilizing EPA 8015 and 8020 methodologies, respectively. The analytical results for soil <br /> samples are summarized in Table 1. Laboratory data sheets and chain-of-custody documentation <br /> i6- are included in Appendix B. <br /> 2_3 Soil Disposal <br /> On June 14, 1999, ATC personnel transported six drums of soil cuttings generated during the <br /> advancement of the soil borings from the Royal Oak Pump Station to the French Camp Landfill in <br /> LW Stockton, California for disposal. All analytical data from the soil samples indicated the soil <br /> cuttings contained no detectable concentrations of petroleum hydrocarbons. ATC was contracted <br /> by the City of Stockton to dispose of the soil cuttings in the City of Stockton owned French <br /> ` Camp Landfill. A copy of the weigh ticket for disposal is included in Appendix C. <br /> 3.0 SUBSURFACE CONDITIONS <br /> 3_1 Geolo>ry <br /> L& <br /> Soil from the surface to depths between 16.5 to 20 feet bgs and 21.5 to 25 feet bgs consisted of <br /> silt with sand, elastic silt with sand, and silty sand. Well graded sand was encountered in borings <br /> r`. SBI and SB2 between 11.5 to 15 feet bgs and 16.5 to 20 feet bgs. Soil from depths between 21.5 <br /> to 25 feet bgs and approximately 41.5 feet bgs consisted generally of lean clay. Soil in boring <br /> SBI from depths between 36.5 to 40 feet bgs and 51.5 feet bgs, the maximum depth explored, <br /> consisted of silt with sand and sandy elastic silt. <br /> L.2- Hydroeeology <br /> LM <br /> Groundwater was encountered in soil borings SBI, SB2, and SB3 at approximately 35 feet bgs. <br /> Based on groundwater gradient data from nearby sites, the estimated groundwater flow direction <br /> beneath the site is to the northeast. The groundwater data from the Lines of Equal Elevation of <br /> Groundwater in the Flood Control & Water Conservation District Fall 1997 Groundwater <br /> Le Report was inconclusive for this location. <br /> rV <br /> w;116393keports\sumi.doc 3 <br />