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Work Plan for Additional Site Assessment 3 <br /> The Southland Corporation,Store#17647, 1048 W.Yosemite Ave. Manteca CA October 26, 1999 <br /> TASK 2: SOIL BORINGSISOIL SAMPLING <br /> IT Corporation will drill three soil borings at the locations shown on Figure 2 using a rotary drilling rig <br /> equipped with 8-inch-diameter hollow-stem augers. The borings will be drilled to approximately 20 feet <br /> below ground surface (BGS) depending on first encountered groundwater, and will be used to characterize <br /> and delineate the extent of adsorbed petroleum hydrocarbons adjacent to the former UST pit and product <br /> lines. It is anticipated that groundwater will be encountered approximately 13 feet BGS based on previous <br /> site assessments. <br /> Soil samples will be collected from each soil boring at 5-foot intervals to total depth of the boring <br /> beginning at 5 feet BGS using a split-spoon sampler lined with 2-inch-diameter by 6-inch-long brass <br /> sample tubes. Drilling equipment will be steam cleaned before drilling, and sampling equipment will <br /> be cleaned between each sampling interval. Each soil sample will be screened for hydrocarbon vapors <br /> using a flame/photo-ionization detector(FID/PID). Soils encountered during drilling will be logged using <br /> the Unified Soil Classification System by a IT Corporation field geologist, working under the supervision <br /> of a California registered geologist. One sample tube from each sampling interval will be sealed with <br /> teflon sheets, capped, taped, labeled, and placed on ice in an insulated container. Each soil sample <br /> will be analyzed by a State-certified analytical laboratory for BTEX, MTBE, and TPH-G by EPA methods <br /> 8020/8015 modified and for MTBE and other oxygenates by EPA Method 8260. An estimated two soil <br /> samples from each boring will be analyzed. <br /> All soil generated through drilling will be placed in Department of Transportation (DOT)-approved <br /> 55-gallon drums pending characterization and disposal. Water generated by steam cleaning will be <br /> temporarily stored on site in DOT-approved 55-gallon drums pending characterization and disposal. <br /> TASK 3: WELL CONSTRUCTIONIDEVELOPMENTIGAUGINGISAMPLING <br /> A groundwater monitoring well will be constructed in each boring of 2-inch diameter Schedule 40 poly- <br /> vinyl-chloride (PVC) casing with flush threads and 0.020-inch-slot well screen. The well screen for <br /> each monitoring well will be installed from approximately 10 to 20 feet BGS. A sand filter pack will be <br /> placed around the well screen to a maximum height of 2 feet above the top of the screen. The well will <br /> be sealed with hydrated bentonite to approximately 5 feet BGS, followed by a neat-cement grout to <br /> grade containing a mixture of 95 pounds of Portland Type I/II cement to 5 gallons of clean water. The <br /> wellhead will be protected at the surface by a locking, expandable cap and traffic-rated street box(with <br /> watertight bolted lid)set in concrete. These wells will be used to characterize and delineate the extent <br /> of dissolved petroleum hydrocarbons and oxygenates. <br /> 17647wkp.LTR <br />