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08 March 2005 AGE-NC Project No. 02-0962 Page 7 of 9 Following sample collection,each preserved sample sleeve will be labeled with the boring location, depth,time,date,and sampler's initials.Appropriately sealed and labeled samples will be placed in a chilled container and transported under chain of custody to a DHS-certified laboratory for analysis for the constituents listed in Section 3.2.. 4.2. WELL COMPLETION AND WELL ELEVATION SURVEY The three pilot soil borings will be completed as ground water monitoring wells utilizing 2-inch diameter, Schedule 40 PVC blank well casing and 0.020-inch slotted well screen installed from 40 feet to 60 feet bsg. After installing the well casing in each pilot boring, a filter pack material consisting of pre-washed#2/12 Lonestar sand will be added through the augers from total depth to approximately 2 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 2-foot bentonite chip seal will be placed above the filter pack to minimize the potential for grout penetration into the screened section of the 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 pellets will be allowed to hydrate for a minimum of hour prior to grouting. The remaining annular space will be filled to within 1 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.The grout will be placed by pumping through a tremie pipe. A grouting inspection will be scheduled with SJCEHD personnel. A proposed monitoring well construction diagram is depicted on Figure 3. Following completion of the monitoring wells,well elevations and locations will be surveyed by a California-licensed surveyor relative to a City of Lodi elevation benchmark. 4.3. WELL DEVELOPMENT 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 with a Waterra inertia pump to finish the removal of fine-grained sediment. Developmental purging activities will be continued until field parameters(pH,electrical conductivity,and temperature)have stabilized and purged water is visually sediment-free. Advanced GcoEnvironmental,Inc.