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15 March 2005 AGE-NC Project No. 04-1168 Page 7 of 9 The 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 I/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. The SJCEHD will be notified for grout inspection at least 48 hours prior to conducting grout procedures.A traffic-rated well box will then be installed over the well casing.The monitoring well construction details are illustrated in Figure 3. 4.3. 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 readings(pH,electrical conductivity,and temperature)have stabilized.Additionally, each well head location and elevation will be surveyed by a licensed surveyor. 4.4. GROUND WATER SAMPLING PROCEDURES Ground water sample collection will be performed in accordance with the SJCEHD's Recommended Groundwater Sampling Guidelines, dated 15 February1995. 4.4.1. Static Water Level Measurements Before purging and sampling during ground water monitoring events, 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 a reference point marked at the top of the PVC.well casing.Before and after each use, the water level indicator will be washed in an Alconox solution and rinsed with water. 4.4.2. Well Evacuation Subsequent to measurement of depth to water and-prior to sampling,the well will be purged using an inertia pump or a disposable bailer to ensure that the sample is representative of the formation, rather than water standing in the well casing. The well will be purged until: 1) a minimum of three casing-water volumes has been removed from the well; and/or 2)the field-measured ground water parameters,pH,temperature and conductivity have stabilized.However,if a well is purged dry prior to evacuating three casing volumes, a ground water sample will be collected following 80 percent recovery of ground water level or after a minimum of 1 hour but within 8 hours of well evacuation. Advanced GeoEnvironmental,Inc.