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23 December 2005 AGE-NC Project No. 04-1045 Page 4 of 6 water monitoring wells. Soil samples will be collected from each soil boring at five-foot intervals. Relatively undisturbed soil samples will be collected in each of the borings using a California modified split-spoon sampler fitted with 2-inch diameter,6-inch long brass sleeves.Upon removal from the sampler,the sample sleeves will be separated with a knife.The exposed ends of the second sleeve will be covered with Teflon sheets,capped and sealed with tape. Soils sampled in the borings will be visually classified by an AGE geologist in accordance with the Unified Soil Classification System(USCS).Additionally,soil samples will be field screened for the presence of volatile organic compounds using an organic vapor meter(OVM),equipped with a photo ionization detector(PID). Soil sample descriptions and OVM readings will be recorded on a log for each boring. 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 with ice and transported under chain-of-custody procedure to a DHS-certified laboratory. 3.2. WELL COMPLETION AND WELL ELEVATION SURVEY The 8.25-inch diameter pilot borings will be single-completed as a ground water monitoring wells utilizing 2-inch diameter schedule 40olwinvlchloride (PVC) 0.020-inch slotted well screen and blank well casing. A 20-foot length of well screen is anticipated for installation of the monitoring well. A proposed monitoring well construction diagram is depicted in Figure 3. After installing the well casing in each pilot boring,a filter pack material consisting of pre-washed 43 sand will be added through the augers over the screen interval to approximately 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 to minimize the potential for grout penetration into the screened section of the well.The bentonite seal will be formed by pouring bentonite chi s into the annulus and allowing them to settle on the filter pack. The bentonite chips will be a owed to hydrate for a minimum of one-half hour prior to grouting. The remaining annular space 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. The grout will be placed by pumping_through tremmie pipe. A grouting inspection will be scheduled with EHD personnel. 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.