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27 February 2019 AdvancedGeo AGE Project No. 08-1650 Environmental Page 5 of 6 All grab groundwater samples will be analyzed for the constituents listed in Section 2.3. and will be collected into laboratory-supplied, non-preserved amber liters and preserved 40-ml Volatile Organic Analysis (VOA) vials. Each sample container will be labeled with sample designation, time, date and sampler's initials. 3.4. MONITORING WELL COMPLETION The pilot soil boring will be completed as a groundwater monitoring well by installing well casing, filter pack and sealing materials into the borehole through the interior of the hollow-stem augers. A 2-inch diameter schedule 40 polyvinylchloride (PVC) 0.020-inch slotted well screen and blank well casing be installed in the borehole. Well screen will be placed from 20 feet to 40 feet bsg. After installing the well casing, filter pack material consisting of pre-washed #3 sand will be added from the bottom of the borehole to approximately two feet above the screened interval. Following placement of the filter pack, the well will be surged to assist filter pack settling. Additional sand will be added if settling occurs. A nominal two-foot bentonite seal (chips) will be placed above the filter pack to minimize the potential for grout penetration into the screened section of the well. The bentonite seal will be formed by pouring bentonite chips into the annular space between the hollow-stem augers and well casing and allowing them to settle on the filter pack. Bentonite chips will be hydrated a minimum of 30 minutes or as specified by the manufacturer prior to grouting using five gallons of water. Remaining annular space above the bentonite seal 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. Grout will be placed by pumping through tremie pipe. A flush mounted well cover will be installed at the surface and will be locked to prevent accidental filling. The SJCEHD will be notified for grout inspection at least 48 hours prior to conducting grouting procedures. A cut view diagram of the proposed shallow well is included as Figure 7. 3.5. 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, the well head elevation and GPS location coordinate will be surveyed by a licensed surveyor.