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The single soil boring will be drilled to a depth of approximately 90 feet bgs The final total depth of the soil boring will be approximately five feet below the depth of the first encountered groundwater- bearing zone The boring will be advanced with a truck-mounted drill ng using 8-inch outside- diameter hollow stem augers Soil samples will be collected at five-foot intervals using a modified California split spoon sampler, lined with two-inch diameter brass sleeves A field geologist will log all soil samples for hydrogeologic and lithologic characteristics according to the Unified Soil Classification System and screen each sample for any hydrocarbon vapors using an organic vapor monitor, equipped with a photolonization detector (PID) Based on the PID measurements, up to six soil samples will be seated with Teflon® paper and plastic end caps, labeled and transported in an iced cooler under chain-of-custody documentation to a state of California certified hazardous waste testing laboratory Prior to soil sample submission to the laboratory, PHSIEHD will be consulted Upon encountering saturated soil and groundwater in the soil boring, the boring will be advanced an additional five feet into the saturated zone To collect a groundwater-grab sample, a two-inch diameter polyvinyl chloride (PVC) temporary well will be constructed and installed in the borehole The temporary well will consist of 10 feet of flush-threaded and machine-slotted (0 020-inch) well screen spanning approximately five feet above and five feet below the static groundwater level Blank PVC casing will thread into the top of the well screen and extend to the surface Neither a sand pack nor a well seal will be installed in the temporary well Prior to groundwater-grab sampling, the temporary well will be purged of approximately three well volumes using a weighted, dedicated and disposable bailer During purging, groundwater temperature, pH and electrical conductivity will be recorded Once the groundwater in the ' temporary well is purged and recharged to at least 90% of its original groundwater column thickness, a groundwater-grab sample will be collected The groundwater-grab sample will be collected with the disposal bailer and poured into laboratory-supplied containers The containers will be labeled and transported in an iced cooler under chain-of-custody documentation to a state of California certified hazardous waste testing laboratory Once the soil and groundwater-grab sampling is completed, the temporary well will be removed and the sod boring will be abandoned with 20 1 cement bentonite grout, installed to the bottom of the borehole using a tremae pipe Following borehole abandonment, the surface composition will be restored Waste soil generated during the drilling of the soil boring will be stockpiled at the site using a base and cover of plastic sheeting Proper disposition of the waste sod will be based on the results of the sod sample analyses Equipment nnsate water and purged groundwater will be stored on-site in 55-gallon drums pending waste profiling and proper disposition 8