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27 February 2015 AGE-NC Project No. 96-0235 Page 8 of 10 4.2. PILOT SOIL BORING ADVANCEMENT AND SOIL SAMPLING Pilot soil borings for installation of deeper monitoring wells will be advanced to depths of approximately 60 feet bsg (deep wells), utilizing a truck- or track-mounted drill rig equipped with 8.25-inch diameter hollow-stem augers. The hollow-stem auger drilling method is performed without the introduction of drilling fluids and allows for the construction of wells with minimal introduction of disturbed soil. Soil cuttings and rinseate will be containerized in properly labeled DOT-approved 55-gallon drums or a 10-yard soil bin and stored in an area on the site generally lacking public access. Disposal alternatives for rinseate and stockpiled soil will be selected based on results of a laboratory analysis. Soil samples for data collection and soil evaluation will be collected from selected borings through the hollow stem of the augers. Relatively undisturbed soil samples will be collected using a California split-spoon sampler loaded with three 2-inch by 6-inch steel or brass sleeves. The sampler will be driven by dropping a 140-pound hammer from a height of 30 inches. The sampler will be driven 18-inches or until refusal into the undisturbed soil below the bit on the lead auger. Upon removal from the sampler, the sample sleeves will be separated. Based on the amount of sample recovery, a selected z sample sleeve will be preserved for possible laboratory analysis. Subsequently, the exposed ends of the sleeve will be covered with Teflon sheets, plastic end caps and sealed with tape. Following sample collection, each preserved sample sleeve will be labeled with the boring location, depth, time, date and sampler's initials. Appropriately sealed and labeled samples will be placed in a chilled container under ice and will be transported under chain of custody procedure to a certified laboratory. During drilling, soil samples will be collected in selected borings at five-foot intervals (beginning at 35 feet bsg) for logging purposes; selected soil samples will be analyzed by a California Department of Public Health l H)-certified laboratory for the constituents listed in Section 3.3. J� e Laboratory reports for soil analysis, testing methods, laboratory quality assurance/quality control (QA/QC) reports, and sample chain of custody documentation will be presented in a report with findings and recommendations. Soil encountered in the borings will be visually classified by an AGE geologist or environmental scientist in accordance with the USCS. Additionally, soil samples will be field-screened for the presence of volatile organic compounds using a PID. 4.2. WELL COMPLETION AND ELEVATION SURVEY The pilot soil borings will be completed as groundwater monitoring wells utilizing a 2- inch diameter, Schedule 40 PVC blank well casing and 0.020-inch slotted well screen Advanced GeoEnvi ron mental Inc.