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' 27 June 2002 . AGE-NC Project No. 98-0520 ' Page 3 of 8 Each well was completed by placing the PVC well casing assembly through the hollow stem of the ' augers to the total depth of the boring. The augers were incrementally raised as #3 Lonestar sand (filter pack)was slowly poured down the annulus between the well casing and the inner wall of the hollow stem auger. The filter pack was placed adjacent to the screened casing from'the bottom of ' the boring to a point approximately two feet above the top of the screen.Following placement of the filter pack, a surge block.was inserted into the PVC casing and.was lowered and'raised (surged) . ' repeatedly for approximately 10 minutes. The depth to the top of the filter pack was measured and bentonite chips were poured into the annulus and allowed to settle on the filter pack. Five gallons of tap water were used to hydrate the bentonite chips for one-half hour prior to grouting. The ' remaining'annular space was sealed with portland type LIU neat cement mixed with no more than 6 gallons of water per 94-pound sack of cement.The grout was placed by pumping through the center of the auger while the augers were incrementally raised. The as-built monitoring well diagrams are presented in the boring logs(Appendix A). ' 2.1.5. Monitoring Well Development Activities " On 13 November 2001, monitoring wells MW-6 and MW-8 through MW-10 were developed ' utilizing a stainless steel hand bailer and 2-stage. pump. Ground water was purged from each monitoring well until ground water was visually sediment free; approximately 21 gallons of water• were removed from MW-9 and MW-10,32 gallons from MW-8 and 40 gallons from MW-6.Ground ' water temperature,pH-and conductivity were measured at regular intervals during purging using an- Oakton water analyzer. Purged ground water was containerized in properly labeled DOT-approved model 55-gallon drums and was stored on-site. Field sheets and data are included in Appendix B. ' 2.2., QUARTERLY WELL MONITORING PROCEDURES Monitoring wells MW-1 through MW-6 and MW-8 through MW=10were sampled on 05 December 2001 in accordance with the AGE-prepared Preliminary Site Assessment Work Plan, dated 30 November 1998, 2.2.1. Well Monitoring and Evacuation A Solinst water level meter was used to measure the depth to ground water in the nine wells relative to the tops of the well casings.After the depth-to-ground water measurements were collected,casing' water in the monitoring wells was evacuated using plastic disposable bailers. Approximately 6 gallons of water were evacuated from each of the monitoring wells,equivalent to three casing-water • volumes per well. Advanced GeoEnvironmental,Inc.