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23 March 2001 AGE-NC Project No 97-0301 ' Page 6of11 One soil sample (MW5-35) was submitted for microbial enumeration and physicochemical ' laboratory analysis The results of the analysis indicated that hydrocarbon-degrading microorganisms were detected at 25,000 CFU (colony forming units) per gram The laboratory indicated that the physicochemical conditions at the site were within the range necessary to support microbial growth ' and bioremedial activity Copies of the microbial enumeration and physicochemical laboratory reports are included with Appendix F I ' 4.0. QUARTERLY GROUND WATER MONITORING PROCEDURES On 28 December 2000, ground water monitoring and sampling was performed at the site on wells MW-1 through MW-7 Ground water monitoring procedures for the site were performed as outlined ' in Addendum to Monitoring Well Installation Work Plan - September 2000, dated 29 September 2000, prepared by AGE and approved by the PHS-EHD by letter dated 15 October 2000 ' 41 MONITORING WELL PURGE PROCEDURES Depths to ground water were measured in each well from the tops of the well casings at the site to lip the nearest 0 01-foot utilizing a Sohnst water level meter Ground water elevation in each well at the site was calculated by subtracting the measured depth to ground water from the surveyed casing ' elevations (Table 3) Ground water elevations were plotted and contoured on a scaled site map (Figure 12) After water levels were measured, approximately 10 to 30 gallons of ground water(a minimum of three casing water-volumes per well) were removed from wells MW-1 through MW-7 utilizing a two- stage submersible pump 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 G Purged ground water was containerized in 55-gallon drums and stored at the site 4 2 GROUND WATER SAMPLING Following well purging, ground water levels in the monitoring wells were allowed to achieve a minimum of 80 percent recharge prior to sample collection Ground water samples were collected from the purged wells utilizing new,disposable polyethylene bailers,one 1-liter amber bottle without a preservative and 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 Advanced GeoEnvironmental,Inc