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13 April 2001 ' AGE-NC Pro3 ect No 96-0232 Page 7 of 14 ' monitoring activities concurrently, the Three B's Truck Plaza tabulated ground water elevation results are in Appendix G ' San Joaquin County municipal groundwater wells(CSA-1 and CSA-2) are normally sampled during Flag City Chevron quarterly monitoring events in accordance with Cleanup and Abatement Order No 5-00-700, however representatives of the San Joaquin County Utilities Distract could not be ' located on 08 and 09 March 2001 to gain access to wells CSA-1 and CSA-2 ' Well MW-10,butted by road base material during street construction,could not be located on 08 and 09 March 2001, the monitoring well was located on 14 March 2001, at which time it was monitored and sampled 3 1 MONITORING WELL PURGE PROCEDURES Depths to ground water were pleasured in the ground water monitoring wells from the tops of the well casings to the nearest 0 01-foot utilizing a Solinst water level meter Ground water elevations '. in each monitoring well at the site were calculated by subtracting the measured depth to ground water from the surveyed well casing elevations (Table 4) Ground water elevations were plotted for First Zone, Second Zone, Secondary Aquifer Zone and Primary Aquifer Zone hydrogeologic flow units as defined in Final Remedzatzon Plan,dated 31 August 2000 Ground water elevation data was contoured on scaled site maps (Figures 3, 4, 5 and 6, respectively) ' After water levels were measured, approximately 6 to 19 gallons of ground water (a minimum of three casing-water volumes per well) were removed from wells MW-1, MW-2, MW4, MW-5, ' MW-6A, MW-6B and MW-7 utilizing a two-stage submersible pump, ground water pumping was initiated at the top of the water column and the pump was slowly lowered to total depth to purge ground water within the entire well casing Temperature, pH and conductivity were measured for ' stabilization at regular purge-volume intervals from each well using a Hydac water analyzer Field data and logs are in Appendix H Monitoring well purged ground water was transferred to the ground water remediation system holding tank for treatment and disposal ' The multi-level monitoring wells MW-8 through MW-13 were purged by lowering and raising a 3/8- inch outer diameter, length-discrete polyethylene hose equipped with a ball-valve water tip through the top chambers into the specific water-charged screened section Approximately 1 to 5 gallons of ground water(a mimmum of three casing-water volumes per well)were removed from the multi- level monitoring wells Multi-level well purged ground water was transferred to the ground water remediation system holding tank for treatment and disposal Field data logs are included with Appendix H Advanced GeoEnvironmentai,Inc