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28 June 2001 AGE-NC Project No. 95-0103 Page 7 of 9 4.3. WELL DEVELOPMENT/SAMPLING Development of the proposed extraction wells will consist of a combination of bailing with a stainless steel bailer 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 ground water evacuation (purging)with a submersible pump to finish the removal of fine-grained sediment. Developmental purging activities will be continued until field parameter (pH, electrical conductivity, and temperature) readings have stabilized and purged water is visually sediment-free. 4.4. GROUND WATER EXTRACTION ACTIVITIES Ground water will be extracted from the three newly installed extraction wells (EW-1 through EW-3); the soil vapor extraction wells VE-1,VE-6 and ground water monitoring wells MW-1, and MW-4 if necessary, (Figure 3)utilizing submersible, 4-inch(2-inch for monitoring wells) diameter Grundfos Rediflow self-priming downhole pumps. Each pump which will be outfitted with automated electronic shut-off controls to control water entering the system. During the pumping operation, the estimated ground water extraction flow rate will be between three and four gpm, if multiple wells are used. AGE anticipates total ground water extraction flow between three and four GPM from an individual well, therefore a surge pumping technique may be implemented at each well head,if multiple wells are utilized,to control the volume of produced water.The total treatment flow will be five gpm. From each well head, extracted ground water will be routed through a sediment pre-filter and into a 750-gallon holding tank, from which it will pass through a process pump, to the in-line GAC vessels. The GAC treatment is intended to adsorb hydrocarbons through carbon adsorption. Sample ports will be located in appropriate position after the process tank(holding) after the GAC vessels for monitoring purposes. A generalized design of the treatment system is depicted in Figure 3. 4.4.1. Ground Water Extraction Piping System A network of two-inch diameter and one-inch, schedule 40 PVC piping already exists on the site; connected to vapor extraction wells and monitoring well MW-4. Any additional trenching will be installed in a trench approximately Moot wide by I Meet deep. PVC schedule 80 PVC conduits will be installed for ground water extraction and for pump power control within the new trenches for the newly installed extraction wells. Advanced Geo Environmental,Inc.