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N 15 June 2005 AGE-NC Project No. 03 - 1070 Page 6 of 7 surface with a cement grout. The grout mixture will consist of Type VII portland neat cement and not more than 6 gallons of water per 94-pound sack of cement. The grout will be placed by pumping through tremie pipe. The EHD will be notified for grout inspection at least 72 hours prior to conducting grouting procedures. A traffic-rated well box will then be installed over the well casing. An extraction well diagram is illustrated on Figure 3. 4.3 , WELL DEVELOPMENT AND SURVEY Development will consist of a combination of bailing to remove the major portion of fine-grained sediment from inside the well, surging to flush out or draw in sediment from the filter pack, and additional bailing to finish the removal of sediment. Development activities will be continued until field parameter (pH, electrical conductivity, and temperature) readings have stabilized. After development, the top of each well casing (well head) will be surveyed to determine its elevation relative to mean sea level and its X, Y and Z global positioning satellite coordinates based on longitude and latitude measurements. 4.4. GROUND WATER EXTRACTION (AQUIFER PUMPING) TEST A draw-down pilot test will be performed to evaluate feasibility of ground water extraction and radius of ground water influence from a single well. A 4-inch diameter Grundfos Rediflow self- priming submersible pump will be used to extract water from extraction well EW- 1 to induce a decline in the static water level in EW- 1 . Solinst Leveloggers Model 3001 instruments will be deployed in observation wells MW- 1 , MW-2, MW-3 and the extraction well to obtain draw-down measurements at 1 -minute intervals to measure difference in ground water levels before and during well pumping. The Leveloggers utilize ceramic pressure transducers to record water level data, which can be downloaded to a computer via an RS232 Optical infra-red data reader/port connected to a computer. The Levelogger data will be compared to water level measurements taken manually fromthe observation wells at timed intervals. Barometric measurements will be collected from a 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-hourpump 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. Advanced GeoEnvironmental, Inc.