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19 November 2007 AGE-NC Project No. 05-1306 Page 5 of 7 3.2. WELL COMPLETION Alter drilling to total depth, the borings will be completed as 2-inch diameter monitoring wells. Shallow wells MW-10 and MW-11 will be completed with a 20-foot length of Schedule 40 polyvinylchloride (PVC) 0.020-inch slotted well screen attached to blank casing extending to near- surface; deep well MW-12 will be completed with a 5-foot length of 0.020-inch slotted well screen attached to blank well casing. After the well casing is installed, a filter pack material consisting of pre-washed #3 Lonestar sand will be added from the bottom of the borehole to approximately one to two feet above the screened interval. Following placement of the filter pack, the well will be surged to assist in settling the filter pack. Additional sand will be added if settling occurs. A nominal two-foot bentonite seal will be placed above the filter pack of the monitoring wells to minimize the potential for grout penetration into the screened section of the well. For the shallow wells, the bentonite seal will be formed by pouring bentonite chips into the annulus and allowing them to settle on the filter pack. The bentonite chips will be hydrated using approximately five gallons of tap water and will be allowed to hydrate for a minimum of one-half hour prior to grouting. For the deep well (MW-12), the bentonite seal will be formed by pouring coated bentonite pellets into the annulus and allowing them to settle on the filter pack. The bentonite pellets will be allowed to hydrate for a minimum of one-half hour prior to grouting. The remaining annular space in each well will be filled within one foot of the ground surface with a cement grout. The grout mixture will consist of Type I/II portland neat cement and not more than 6 gallons of water per 94-pound sack of cement. A grouting inspection will be scheduled with EHD personnel. Proposed monitoring well construction diagrams are depicted in Figures 3 through 5. 3.3. WELL DEVELOPMENT AND ELEVATION SURVEY The wells will be developed at least 48 hours after installation to allow for the grout to set. Development of the proposed 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 Waterra bailing pump to finish the removal of fine-grained sediment.Developmental activities will continue until readings of field parameters (pH, electrical conductivity, and temperature) have stabilized and purged water is visually sediment-free. Following completion of the monitoring wells, well elevations and locations will be surveyed by a California-licensed surveyor relative to a City of Stockton elevation benchmark. Advanced GeoEnvironmental,Inc.