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Harding Lawson Associates <br /> October 30, 1996 <br /> 36371 3 <br /> Mr. Steve Sasson <br /> SJCEHD <br /> Page 2 <br /> The lowermost tube from each sample interval will be removed from the sampler and immediately <br /> capped with Teflon-lined plastic end caps, labeled, and placed in an ice-chilled cooler for transport <br /> to a State-certified analytical laboratory. Samples will be recorded on a standard HLA chain-of- <br /> custody form to document sample identification and handling. The remaining soil sample from <br /> each interval will be checked for hydrocarbon stains and monitored for VOC vapors using a <br /> photoionization detector(PID) which is calibrated daily. The PID will be equipped with a 10.2 <br /> electron-volt lamp and calibrated to a 100 part per million(ppm) isobutylene standard. <br /> The borings will be logged under the supervision of a California registered geologist. The soils will <br /> be visually classified using the Unified Soil Classification System (USCS); soil classifications and <br /> other field observations are recorded on standard HLA field logging forms. HLA has assumed that <br /> the soil borehole can be drilled with conventional hollow stem auger drilling equipment. Drilling <br /> equipment will be steam cleaned prior to each use. Soil sampling equipment will be washed in a <br /> residue-free detergent(such as Alconox, Liquinox,TSP, etc.) and rinsed in tap water and deionized <br /> water prior to each use. After drilling is terminated, the borings will be grouted with neat cement in <br /> accordance with SJCEHD requirements. Soil cuttings generated during drilling activities will be <br /> stockpiled on visqueen. The cuttings will be retained on site pending analytical results. <br /> Task 2 -Analytical Program <br /> A maximum of four soil samples will be selected from each boring based on subjective field criteria <br /> (PID readings, soil discoloration, and hydrocarbon odors) as well as the objectives of the field <br /> investigation. These samples will be analyzed for total petroleum hydrocarbons as gasoline (TPHg) <br /> and total petroleum hydrocarbons as diesel (TPHd)by Environmental Protection Agency (EPA) <br /> Method 8015M; and also for benzene, toluene, ethylbenzene, and total xylenes (BTEX) with EPA <br /> Method 8020. <br /> Selected soil samples will be analyzed for total lead with EPA Method 7420A or 6010. Samples <br /> selected for analyses will be based on TPHg analytical results. Soluble lead analyses for soil samples <br /> will be performed only on samples for which the total lead concentration exceeds 10 times the <br /> soluble threshold limit concentration(STLC)for lead. <br /> Because the UST was removed approximately 6 years, soil samples are not likely to contain methyl <br /> tertiary butyl ether(MTBE). MTBE is a gasoline additive that was first incorporated into gasoline <br /> formulations ten years ago in California and within the past few years in the Central Valley <br /> (RWQCB, 1996). However, in order to eliminate potential disposal problems at a later date selected <br /> soil samples with high concentrations of TPHg will be analyzed for MTBE. In accordance with the <br /> RWQCB analytical protocol established for confirming false positives and false negatives one sample <br /> will be analyzed for MTBE using EPA Method 8260 (RWQCB, 1996). <br /> .o' <br />