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1 <br /> . 1 <br /> Task 1 . 4 : Install Additional Qr n WatQr M i rin <br /> Recovery Wells <br /> Based on the results of Tasks 1 . 1 to 1 . 3, install <br /> three additional ground water monitoring wells at <br /> the appropriate locations to verify or confirm the <br /> extent of ground water contamination. Two of the <br /> wells will be installed offsite to define the <br /> northeastern boundary of the plume. <br /> Depending on the results of the aquifer test and <br /> construction of the well, the existing onsite <br /> 4-inch well (MW-5) will be converted as a recovery <br /> well . If this is not feasible, however, a third <br /> well will be installed as a recovery well either <br /> onsite or offsite in the presumed center of the <br /> contaminant plume. The exact locations of the <br /> wells will be determined based on the results of <br /> the above tasks. <br /> The wells will be drilled using a 10-inch CME 55 <br /> or 75 hollow stem auger in accordance with <br /> standard procedures and requirements of regulatory <br /> agencies . All necessary permits will be acquired <br /> for all wells that will need to be installed <br /> offsite before commencing with the drilling <br /> activities. Ground penetrating radar (GPR) survey <br /> or other geophysical, methods may be required to <br /> determine the location of underground utilities <br /> prior to drilling. <br /> During drilling, soil samples will be collected at <br /> 5-foot intervals beginning at 5 feet below grade <br /> and terminating at the capillary fringe of the <br /> first saturated zone encountered. Samples will be <br /> collected from the saturated zone for analysis of <br /> physical properties to determine aquifer <br /> characteristics . Soil samples will be obtained <br /> through a split spoon sampler lined with stainless <br /> steel tubes . The samples recovered for analysis <br /> will be sealed airtight with teflon tape and <br /> plastic caps, and placed immediately into an iced <br /> cooler. <br /> Each ground water monitoring well will be <br /> completed to a depth of about 20 feet below the <br /> top of the first saturated zone encountered. Each <br /> well will be constructed of clean 4-inch diameter <br /> Schedule 40 PVC pipe, with 0 . 020-inch <br /> perforations, and the required gravel packs . The <br /> recovery well will be installed and constructed <br /> based on site-specific hydrogeologic conditions <br /> . and the nature of contamination encountered. <br /> 4 <br />