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20 April 2007 AGE-NC Project No . 95 -0167 Page 8 of 10 data will be compared to water level measurements taken manually from the observation wells at timed intervals. Barometric measurements will be collected from dedicated pressure transducers to determine the atmospheric influence on the pressure transducers values. From this data the results of the draw down test will be adjusted to correct for any changes in atmospheric pressure. During the 8-hour pump test, the ground water pumping rate will be increased every 2-hours, starting at 2 gallons per minute (GPM), to achieve the optimum pumping rate for the greatest draw-down influence. If the decline of the ground water level is not satisfactory within the first eight hours of the pilot test, additional testing will be performed to achieve sufficient ground water draw-down. The 24-hour pump test will be conducted at a constant rate determined by the results of the 8-hour pump test and the available storage or handling capacity for the produced ground water. Results of the 24-hour pilot test will be utilized to assess the feasibility of ground water extraction at the site. During the 8-hour pump test ground water samples will be collected from the effluent line at the initiation ofthe test and approximately every two hours after pumping is initiated and a final sample just before the end of the pump test. The samples will be analyzed by a DHS-certified laboratory for the same constituents listed in Section 3 .5 . . All extracted ground water will be stored in a temporary, above-ground (Baker-type), storage tank. Subsequently, the purged ground water will characterized and be transported to a suitable waste disposal/recycling facility. 4.4 SVE WELL INSTALLATION AND PILOT TESTING Following completion of the drilling of the pilot boring, one 4-inch diameter Schedule 40 PVC 0.030-inch slotted well screen and casing will be installed adjacent to boring P3 . A 10 foot section of well screen will be installed, screened from approximately 5 to 15 feet bsg. The well casing, filter pack and sealing materials will be placed into the borehole through the interior of the hollow-stem augers. After installing the well casing, filter pack material consisting of pre-washed 43 Lonestar sand or coarse sand will be added to the remaining annular space from the bottom of the borehole to approximately one foot above the screened interval. A nominal two-foot thick bentonite seal will be placed above the filter pack to minimize grout penetration into the screened section of the well. The bentonite seal will be formed by pouring bentonite chips into the annular space between the auger and the well casing and allowing the chips to settle on the filter pack. The bentonite chips will be allowed to hydrate for a minimum of one-half hour prior to grouting using a minimum of five gallons of water. The remaining annular space above the bentonite seal will be filled to within three feet of the ground surface with a cement grout. The grout mixture will consist of Portland, neat cement and not more Advanced GeoEnvironmental, Inc.