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t+ <br /> 3.2 Soil Sampling <br /> Grab samples of cuttings were logged continuously during <br /> drilling for identification of stratigraphy and detection of <br /> hydrocarbon contamination. Field screening of volatile <br /> organics emitted from the soils was conducted with a <br /> photoionization detector (PID) . The PID readings are <br /> plotted adjacent to the soils tested on the well log <br /> (Appendix I) . Discreet samples were taken at five foot <br /> intervals starting between ten and twenty feet below grade <br /> a depending on the depth of samples collected during the <br /> original tank pull. These samples were collected in two <br /> inch diameter brass ti,.bes using a California modified <br /> sampler. Samples were collected, preserved and transported <br /> under chain-of-custody in accordance with WaterWork's Soil <br /> Sampling Protocol (Appendix II) . The samples from borings <br /> SB--1 and SS-3 were analyzed for benzene, toluene, <br /> ethylbenzene, xylene (BTEX) by EPA 8020 and total petroleum <br /> hydrocarbons as gasoline (TPH-G) by California Department of <br /> Health Services (DHS) test methodology. In addition, the <br /> 30.5 foot sample from SB1 was analyzed for TPH as paint <br /> thinner (TPH-PT) by DHS methodology. Samples from boring <br /> SB2 were analyzed by EPA 8010 to detect Chloroform and <br /> Trichloroethane. The minimum detection level for BTEX in <br /> soil samples analyzed by B.C. Laboratories is 0.02 ppm; for <br /> TPH as gasoline and paint thinner in .soil samples is 5.0 <br /> Ppm. The detection limit for the EPA 8010 constituents is <br /> 0.70 ppb. <br /> 3.3 Quality Assurance/Quality Control Program <br /> WaterWork's Quality Assurance .and Quality Control (QA/QC) <br /> Plan, Appendix III, outlines the field and laboratory <br /> procedures followed to obtain representative data. The <br /> previously referenced monitoring and sampling protocols <br /> (Appendix II) outline additional QA/QC procedures. The <br /> field investigation was conducted under the direct <br /> supervision of Russell Juncal, California Registered <br /> Geologist No. 3864, and Nora H. Kataoka, California <br /> Registered Civil Engineer No. 38322. <br /> 4.0 SUBSURFACE CONDITIONS <br /> _ -4.1 _Field Inspection- <br /> The <br /> nspection The soils encountered during drilling consisted generally of <br /> clays and silts in the upper 21 feet with sands and silty <br /> sands between 21 and 31 feet in boring SBI. Moderate <br /> gasoline hydrocarbon odors were rioted in the. upper 17 foot <br /> sail interval in boring SB1. Slight product odor; noted as <br /> a solvent/thinner smell, was recorded in samples. between 17 <br /> and 35- feet below grade. PID readings ranged from 2.4 to 72 <br /> ppm in this soil interval with the highest reading from the <br /> 3 <br /> k <br />