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28 April 2005 <br /> AGE-NC Project No 97-0351 <br /> Page 9 of 11 <br /> Following sample collection,each preserved sample sleeve will be labeled with the boring location, <br /> depth,time, date,and sampler's initials Appropriately sealed and labeled samples will be placed in <br /> a chilled container and transported under chain of custody to a DHS-certified laboratory for analysis <br /> for the constituents listed in Section 3 2 <br /> 43 WELL COMPLETION AND WELL ELEVATION SURVEY <br /> The three pilot soil borings will be completed as ground water monitoring wells utilizing 2-inch <br /> diameter, Schedule 40 PVC blank well casing and 0 020-inch slotted well screen installed from <br /> 5 feet to 20 feet bsg A monitoring well construction diagram is depicted on Figure 5 <br /> After installing the well casing in each pilot boring, a filter pack material consisting of pre-washed <br /> #2/12 Lonestar sand will be added through the augers from total depth to approximately 1 foot above <br /> the screened interval Following placement of the filter pack, the well will be surged to assist in <br /> settling the filter pack Additional sand will be added if settling occurs <br /> . A nominal 2-foot bentonite chip seal will be placed above the filter pack to minimize the potential <br /> for grout penetration into the screened section of the wells The bentonite seal will be formed by <br /> pouring bentonite pellets into the annulus and allowing them to settle on the filter pack The <br /> bentonite pellets will be allowed to hydrate for a minimum of%2-hour prior to grouting <br /> The remaining annular space will be filled to within 1 foot of the ground surface with a cement <br /> grout The grout mixture will consist of Type 11II portland neat cement and not more than 6 gallons <br /> of water per 94-pound sack of cement The grout will be placed by pumping through a tremie pipe <br /> A grouting inspection will be scheduled with EHD personnel <br /> Following completion of the monitoring wells, well elevations and locations will be surveyed by a <br /> California-licensed surveyor relative to a City of Stockton elevation benchmark <br /> 44 WELL DEVELOPMENT <br /> Development of the proposed wells will consist of a combination of bailing with a stainless steel <br /> bailer to remove the major portion of fine-grained sediment from inside the well, surging to flush <br /> out or draw in sediment from the filter pack,and additional ground water evacuation with a Waterra <br /> inertia pump to finish the removal of fine-grained sediment Developmental purging activities will <br /> be continued until field parameters(pH,electrical conductivity,and temperature)have stabilized and <br /> purged water is visually sediment-free <br /> Advanced GeoEnvironmentai,Inc <br />