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' 15 January 2001 AGE-NC Project No 96-0232 ' Page 13 of 20 ' A coordinated effort was made between Three B's Truck Plaza and Flag City Chevron(6421 Capitol Avenue) to conduct ground water monitoring activities concurrently, the Three B's Truck Plaza tabulated ground water elevation results are in Appendix I 8 1 MONITORING WELL PURGE PROCEDURES ' Depths to ground water were measured in ground water monitoring wells from the tops of the well casings to the nearest 0 01-foot utilizing a Solmst 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 6) Ground water elevations were plotted for First Zone, Second Zone, Secondary Aquifer Zone and Primary Aquifer Zone as defined in Final Remediation ' Plan, dated 31 August 2000 Ground water elevation data was contoured on scaled site maps (Figures 14, 15, 16 and 17,respectively) ' After water levels were measured, approximately 6 to 9 gallons of ground water(a minimum of three casing-water volumes per well) were removed from wells MW-1, MW-2, MW-4, 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 Approximately 9 gallons of ground water were removed from well ' MW-6B before being pumped "dry" 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 J Purged ground water was containerized in 55-gallon drums and was stored on-site in an area lacking general public access 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 minimum of three casing-water volumes per well) were removed from the multi- level monitoring wells Field data logs are included with Appendix J ' 8 2 GROUND WATER SAMPLING Following well purging, ground water levels in all of the above mentioned monitoring wells ' achieved a minimum of 80 percent recharge prior to sample collection Ground water samples were collected from the purged wells MW-1 through MW-7 utilizing new, 2-inch diameter disposable ' polyethylene bailers, ground water samples were collected from the purged wells MW-8 through MW-13 utilizing 1/4-inch diameter polyethylene tubing Ground water samples were transferred into one-liter amber bottles without a preservative and into 40-mi EPA-approved VOA vials containing ' Advanced Geo Environmental,Inc