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I <br /> • <br />' ATTACHMENT D <br /> FIELD AND LABORATORY PROCEDURES <br /> I <br />' Exploratory Drilling and Soil Sampling <br /> The soil borings were drilled using 8-inch hollow-stem auger equipment Borings were <br />' logged by a SECOR International Incorporated scientist using the Unified Soil Classification <br /> System (USCS) and standard geologic techniques under the direction of a registered <br />' geologist Depth discrete groundwater samples were collected using a hydropunch in <br /> separately cored borings adjacent to PSB-1 and PSB-2 Soil samples for logging were <br /> collected at 5-foot depth intervals using a California-modified split-spoon sampler The <br />' sampler was driven a maximum of 18 inches using a 140-pound hammer with a 30-inch drop <br /> Soil samples were collected by advancing 2-inch-diameter brass sample liners into <br /> undisturbed soil, reached through the center of the drill auger Soil samples for cheinmcal <br /> analysis were retained in the brass liners, labeled, and capped with Teflon sheets and plastic <br /> end caps The samples were then sealed in zip-lock bags, placed on ice, and transported to <br /> the laboratory accompanied by the appropriate chain-of-custody documentation <br /> Down-hole dulling and sampling equipment was steam-cleaned prior to and following the <br /> completion of each soil boring Down-hole sampling equipment was washed in a tri-sodium <br />' phosphate or alconox solution between samples <br /> Groundwater Monitoring Well Installation and Development <br /> 1 Each of the groundwater monitoring wells was constructed of 4-inch-diameter schedule 40 <br /> PVC blank casing and 0 020-inch-slot well screen with flush threads A #3-sand filter pack <br />' was installed in the annulus from the bottom of each borehole to at least 2 feet above the top <br /> of the well screen, followed by a well seal consisting of a 2-foot-thick hydrated bentonite <br />' layer overlain by grout to ground surface Each well was secured by a locking expandable <br /> well cap and fitted with a traffic-rated well box set in concrete The wells were developed by <br /> vigorously swabbing over the entire length of the screened interval and purging <br /> Iapproximately 10 casing volumes of water from the well <br /> I <br />