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14 October 2014 AGE Project No , 11 - 1847 Page 5 of 6 3 . 2 . WELL COMPLETION AND ELEVATION SURVEY Adjacent to each deep soil boring , a second pilot soil boring will be advanced to a depth of approximately 40 feet bsg and completed as a groundwater monitoring well utilizing a 2-inch diameter, Schedule 40 PVC blank well casing and 0 . 020-inch slotted well screen installed from 20 feet to 40 feet bsg ; soil samples will not be collected during pilot soil boring advancement. A diagram of the proposed monitoring well construction is depicted in Figure 4 . After installing the well casing in each pilot boring , a filter pack material consisting of pre-washed #3 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 three-foot bentonite 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 chips will be allowed to hydrate for the duration of time specified by the manufacture , prior to grouting . The remaining annular space will be filled to within one foot of the ground surface with a cement grout. The grout mixture will consist of Type 1/11 portland neat cement and not more than 3 gallons of water per 50- L<7 J5 pound sack of cement. The grout will be placed by pouring or pumping through a tremie pipe or auger. A grouting inspection will be scheduled with EHD personnel prior to any application of grout. Following completion of the monitoring wells , each well location will be surveyed at the top of each well casing by a California-licensed surveyor relative to a City of Stockton benchmark and the North American Vertical Datum 88 . 3 . 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 groundwater 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 GeoEnviron rental Inc.