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18 June 2001 AGE-NC Project No. 98-0433 Page 6 of 8 Following completion of fifteen-inch soil boring, a 6-inch diameter recovery well Schedule 40 PVC 0.02-inch slotted well screen and casing will be installed. A 20-foot section of well screen will be installed from a depth of approximately 15 feet to 35 feet bsg,blank casing will extend from 15 feet bsg to the ground surface. The casing, filter pack and well sealing materials will be placed into the borehole through the interior of the hollow-stem augers. After installing the well casing, filter pack material consisting of pre-washed#3 Lonestar sand and pea gravel will be added from the bottom of the borehole to approximately two feet above the screened interval. Following placement of the filter packs, the well will be surged to assist in settling the filter pack. Additional sand will be added if filter pack settling occurs. A nominal 1-foot bentonite seal will be placed above the filter pack. The bentonite chips will be hydrated with five gallons of potable water. The bentonite chips will be allowed to hydrate for a minimum of one-half hour prior to grouting. The remaining annular spaces will be filled to the ground surface with a cement grout. The grout mixture will consist of Type UII portland neat cement and not more than 10 gallons of water per 94-pound sack of cement. The grout will be placed over the bentonite as an annular seal. Grouting procedures will be subject to inspection by PHS-EHD personnel. A traffic-rated well box will be installed over the wells in accordance with San Joaquin County regulations. Following completion of the monitoring wells, well elevations and locations will be surveyed by AGE personnel, relative to monitoring well MW-1. 3.4. WELL DEVELOPMENT 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. 3.5. GROUNDWATER SAMPLING PROCEDURES Groundwater sample collection will be performed in accordance with pertinent applicable sampling protocols. 3.5.1. Static Water Level Measurements Before sampling and during quarterly ground water monitoring, static water level will be measured using an electric water level indicator. Water level data will be recorded to the nearest 0.01 foot from Advanced GeoEnvironmental,Inc.