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ENCON <br /> As part of the laboratory quality assurance/quality control (QA/QC)protocol, the laboratory will <br /> collect and analyze instrument and sampling blanks to evaluate the potential for cross- <br /> contamination from the laboratory equipment and/or sampling materials. A duplicate or replicate <br /> sample will also be collected and analyzed each day to evaluate the precision of the laboratory <br /> analysis. <br /> A tracer gas mixture of n-propanol and n-pentane will be placed around each probe at the ground <br /> surface while sampling to evaluate the potential for ambient air intrusion. The tracer gas will be <br /> included on the list of target analytes. <br /> Soil gas samples will be collected in general accordance with the July 2015 DISC and LARWQCB <br /> "Advisory-Active Soil Gas Investigations." <br /> 5.7 Investigation Derived Waste <br /> No derived solid waste will be generated since the drilling methods involve the use of direct-push <br /> Geoprobe drill rigs that do not generate waste materials. <br /> 5.8 Laboratory Analysis <br /> Soil and soil gas samples will be transported in an iced cooler under chain-of-custody protocol to <br /> a State-certified laboratory for analysis. Selected soil samples shall be analyzed for total petroleum <br /> hydrocarbons in the waste oil range (TPHo) using EPA Method 8015M, volatile organic <br /> compounds(VOCs)using EPA Method 8260B,arsenic metals using EPA Method 6010,pesticides <br /> using EPA Method 8081 and herbicides using EPA Method 8151A. The soil vapor samples will <br /> be analyzed for VOCs using EPA Method 8260B. <br /> 5.9 Backfill Boreholes <br /> Upon completion of the soil and soil gas sampling,ENCON shall backfill each boring with hydrated <br /> granular bentonite pellets and poured distilled water to the bentonite. Each borehole shall be <br /> abandoned and filled with hydrated granular bentonite and the borehole shall be restored to match <br /> the surrounding surfaces. <br /> 6.0 FINAL REPORT PREPARTION <br /> ENCON will summarize the field activities, methodologies, and findings of the subsurface <br /> investigation and provide a technical report that will be submitted to the SJEHD for review and <br /> comment within thirty (30) days after completion of the field work. The Final Report will be <br /> prepared under the direction of a California Professional Geologist and properly stamped by the <br /> PG. <br /> 9 <br />