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30 November 2018 AdvancedGeo AGE Project No. 07-1537 Environmental Page 4 of 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 6 gallons of water per 94-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 SJCEHD personnel prior to any application of grout. 3.3. WELL DEVELOPMENT AND SURVEY Development will consist of a combination of bailing 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 bailing to finish the removal of sediment. Development activities will be continued until field parameter (pH, electrical conductivity, and temperature) readings have stabilized. Additionally, each well head elevation and GPS location coordinate will be surveyed by a licensed surveyor. 3.4. GROUNDWATER SAMPLING PROCEDURES Groundwater sample collection will be performed in accordance with AGE's standard monitoring and sampling procedures, which have been included as Appendix B. 3.5. EQUIPMENT DECONTAMINATION/WASTE MANAGEMENT All sampling tools used for sample collection, except for disposable bailers, will be thoroughly rinsed with clean water after being washed with a solution of Alconox. All down-hole drilling equipment will be pressure washed prior to starting each boring. Cuttings generated during drilling and rinseate generated during drilling and groundwater sampling activities will be containerized in properly labeled DOT-approved 55-gallon drums and stored on-site in an area generally lacking public access. Disposal alternatives will be evaluated based on results of soil and water analysis.