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19 November 2004 AGE-NC Project No. 95-0184 Page 4 of 6 4.0. FIELD PROCEDURES All field procedures will be overseen by an AGE representative under the supervision of a California Registered Geologist. Procedures for pilot boring advancement, soil sample collection, well installation, development and ground water pumping tests are outlined below. 4.1. PILOT BORING AND SOIL SAMPLING The extraction well pilot boring will be advanced using a CME-75HT drill rig equipt with 15-inch diameter hollow-stem augers to advance boring EW 1.Cuttings and rinseate generated during drilling activities will be containerized in properly labeled Department of Transportation(DOT)-approved 55-gallon drums and stored on-site in an area lacking public access. Disposal alternatives will be evaluated based on results of soil and water analysis. Soil encountered in the pilot boring will be collected at five-foot intervals using a California modified split-spoon sampler fitted with three 2-inch diameter,6-inch long brass sleeves.Following sample collection, the exposed ends of the leading or other selected sleeve will be labeled with the boring location,depth,time,date and sampler's initials;the appropriately sealed and labeled samples will be placed under ice in a chilled container and will be transported under COC to a DHS-certified laboratory for analysis. The soil in the two remaining sleeves will be visually classified by an AGE geologist in accordance with the Unified Soil Classification System(USCS)and field-screened for the presence of volatile organic compounds using an organic vapor meter(OVM) equipped with a photo-ionization detector(PID:Thermo Environmental 580B, 10.0eV[or equivalent],calibrated to isobutylene). 4.2. EXTRACTION WELL INSTALLATION Following completion of drilling of the extraction well pilot boring, a 6-inch diameter Schedule 40 PVC 0.020-inch slotted well screen and casing will be installed in the borehole. The well-screen section will be 20-feet in length, extending from approximately 30 feet to 50 feet bsg. The well casing,filter pack and sealing materials will be placed into the borehole through the interior of the hammer casing.After installing the well casing,filter pack material consisting of pre-washed silica sand will be added from the bottom of the borehole to approximately two feet above the screened interval. Following placement of the filter pack, the well will be surged to assist settling the filter pack; additional sand will be added if settling occurs. Advanced GeoEnvironmcntal,Inc.