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31 August 2018 AdvancedGeo <br /> AGE Project No. 14-3002 i i)vironmental <br /> Page 6 of 7 <br /> 3.4.2. Monitoring Well Completion and Elevation Survey <br /> Pilot soil borings will be single-completed as groundwater monitoring wells utilizing 2-inch <br /> diameter schedule 40 polyvinylchloride (PVC) 0.020-inch slotted well screen and blank <br /> well casing. Well screens will be placed from 5 feet to 20 feet bsg. The proposed <br /> monitoring well construction design is presented in Figure 3. After installing the well <br /> casings, a filter pack material consisting of pre-washed #3 sand will be added through the <br /> augers to approximately one foot above the screened interval. Following placement of the <br /> filter pack, the wells will be surged to assist in settling of the filter pack. Additional sand <br /> will be added if settling occurs. A nominal two-foot bentonite seal will be placed above the <br /> filter pack. The bentonite seal will be formed by pouring bentonite chips into the annulus <br /> and allowing them to settle on the filter pack. The bentonite will be allowed to hydrate for <br /> a minimum of one-half hour prior to completing the well. <br /> The remaining annular space will be filled to the ground surface with a cement grout. The <br /> grout mixture will consist of Type 1/11 Portland neat cement and not more than six gallons <br /> of water per 94-pound sack of cement. A grouting inspection will be scheduled with <br /> SJCEHD personnel. <br /> Following completion of the monitoring wells, each well elevation and location will be <br /> surveyed by a California-licensed surveyor relative to a benchmark as the North American <br /> Vertical Datum 88. <br /> 3.4.3. Monitoring Well Development and Groundwater Sampling <br /> If necessary for sampling purposes the monitoring wells will be developed. Development <br /> will consist of a combination of bailing with a stainless-steel bailer to remove the major <br /> portion of fine-grained sediment from inside the well, surging to flush out or draw in <br /> sediment from the filter pack, and additional groundwater evacuation with a disposable <br /> plastic bailer or Waterra inertia pump to finish the removal of fine-grained sediment. <br /> Developmental purging activities will be continued until field parameters (pH, electrical <br /> conductivity, and temperature) have stabilized and purged water is visually sediment-free. <br /> Groundwater sample collection will be performed in accordance with AGE's standard <br /> monitoring and sampling procedures, which have been included as Appendix C. <br /> 3.4.4. Waste Management <br /> Rinseate and soil cuttings generated during drilling and potential groundwater sampling <br /> activities will be containerized in properly labeled, Department of Transportation (DOT)- <br /> approved 55-gallon drums and stored on-site. Disposal alternatives will be evaluated <br /> based on the results of soil and groundwater analysis. <br />