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r r15 February 2002 AGE-NC Project No 99-0559 ' Page 2 of 7 ' On 31 October and 01 November 2001,depth to ground water was measured in wells MW-1 through MW-8 from the tops of the well casings to the nearest 0 01-foot utilizing a Slope 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 1) During the first monitoring event, the depth to ground water measurements collected from the CMT wells was measured against the upper edge of the CMT casing The surveyed point for the CMT wells is a PVC collar surrounding the well casing,therefore,ground water elevations for some of the wells may not be accurate and will be re-monitoring during the next sampling event However, ground water elevations were later plotted and contoured on a scaled site map On 31 October and 01 November 2001,approximately 3 to 3 5 gallons ofound a minimum gr' water( of three casing water-volumes per well) were removed from wells MW-1, MW-3 and MW-4 Iutilizing disposable polyethylene bailers Monitoring well MW-2 was purged,but not monitored due to the presence of free product The multi-level monitoring wells MW-5 through MW-8 were purged I 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 0 15 to 4 gallons of ground water (a minimum of three casing-water volumes per • well) were removed from the multi-level monitoring wells Temperature,pH and conductivity were measured for stabilization at regular purge-volume intervals I in wells MWA, MW-3 and MW-4 using an Oakton water analyzer Temperature, pH and conductivity were measured for stabilization at regular purge-volume intervals in wells MW-5,MW- 6, MW-7 and MW-8 using an ICM water analyzer Field data and logs are included with Appendix A Purged ground water was containerized 1n 55-gallon drums and was stored on-site in an area lacking general public access 2 2 GROUND WATER SAMPLING Following well purging, ground water levels of three two-inch diameter, purged monitoring wells were measured to determine if the 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-4 utilizing,the same 2-inch diameter dedicated,disposable polyethylene bailers,ground water samples were collected from the purged wells MW-5 through MW-8 utilizing 3/8-inch diameter polyethylene tubing Ground water samples were transferred into one-liter amber bottles without a preservative and into three 40-m1 EPA-approved VOA vials containing 0 5 ml 18%hydrochloric acid as a sample preservative Care was taken to ensure that visible air bubbles were not present in the vials after filling and capping Ground water sample containers were labeled with the well designation, date, time, and sampler's initials i IAdvanced GeoEnvironmental,Inc