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i 13 August 2004 AGE-NC Project No . 95-0167 Page 7 of 9 of water. The bentonite chips will be allowed to hydrate for a minimum of one-half hour prior to grouting. 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 IM portland neat cement and not more than 6 gallons of water per 94-pound sack of cement. The grout will be placed by pumping or poring through a tremie pipe. EHD will be notified for grout inspection at least 72 hours prior to conducting grouting procedures. A traffic-rated well box will then be installed over the well casing. A monitoring well diagram depicting well design is illustrated on Figure 3 . 3 .5 . MONITORING 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. After development, the top of each well casing (well head) will be surveyed to determine its elevation relative to mean sea level and its X and Y coordinates based on longitude and latitude measurements. 3 . 6 . GROUND WATER SAMPLING PROCEDURES Ground water sample collection will be performed in accordance with RWQCB guidelines (Tri- Regional Water Quality Control Board Recommendations for Preliminary Investigations and Evaluation of Underground Storage Tanks) sampling protocols. 3 . 6 . 1 . Static Water Level Measurements Before sampling and during groundwater 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 a reference point marked of the top of the PVC well casing. Before and after each use, the measurement device will be rinsed with water. 3 .6 .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, Advanced GeoEnvironmental, Inc.