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01 July 2008 AGE-NC Project No . 97-0301 Page 6 of 8 Following placement of the filter pack, the well will be surged utilizing a 24nch well surge block to assist in settling the filter pack. Additional sand will be added if settling occurs. A three-foot bentonite seal (bentonite chips) will be placed above the filter pack to minimize the potential for grout penetration into the screened section of the well. The bentonite seal will be formed by either pouring bentonite chips into the annulus and allowing them to settle on the filter pack or by using coated bentonite pellets. Bentonite chips or pellets will be hydrated using a minimum of five gallons of tap water. The bentonite chips will be allowed to hydrate for a minimum of one-half hour prior to grouting. The remaining annular space will be filled to the ground surface with a cement grout. The grout mixture will consist of Type 1/11 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. A grouting inspection will be scheduled with SJCEHD personnel. The proposed ground water well construction diagram is depicted in Figure 7. Upon grout completion, an eight-inch diameter, flush mount, traffic rated, steel well box will be installed over the well casings and secured with a bolted, steel well box cover. A reference point will be marked on the top of each well head, and surveyed by a California licensed surveying engineer to the nearest 0.01 foot to determine the elevation relative to a surveyed benchmark and to determine GPS coordinates for tracking on the State Water Resources Control Board (SWRCB) GeoTracker database system. Following installation of well MW- 13, but not less than 48 hours, well development activities will be performed at well MW- 13 . Well 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. 3 .4. SOIL VAPOR EXTRACTION WELL COMPLETION Each SVE well will be completed as a single-casing soil vapor extraction well utilizing 4-inch diameter schedule 40 polyvinylchloride (PVC) 0.030-inch slotted well screen and blank well casing. / Based on geologic conditions, a 20-foot length of well screen from 10 to 30 feet bsg is anticipated for installation of each SVE wells; a diagram for the proposed construction of SVE wells VW- 1 , VW-2 and VW-3 is depicted in Figure 8 . Advanced GeoEnvironmental, Inc.