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12 December 2014 AGE Project No. 12-2169 Page 6 of 7 wells screen will be installed from 50 feet to 65 feet bsg. Diagrams of the proposed wells are depicted in Figures 4 and 5. 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 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 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 pellets into the annulus and allowing them to settle on the filter pack. The bentonite pellets 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/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 a tremie pipe or auger. A grouting inspection will be scheduled with EHD personnel prior to any application of grout. 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 reasonable stabilized and purged water is visually reduced of course sediment. EQUIPMENT DECONTAMINATION/WASTE MANAGEMENT All sampling tools 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. Rinseate and soil cuttings generated during drilling and groundwater sampling activities will be containerized in properly labeled, Department of Transportation (DOT) -approved 55 -gallon drums and stored on-site in an area lacking public access. Disposal alternatives will be evaluated based on the results of soil analysis. Advanced GeoEnvironmental, Inc.