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' 08 October 2002 AGE-NC Project No. 98-0468 Page.3 of 6 2.4. . MONITORING WELL/SOIL BORING COMPLETIONS On 23 February, soil boring B8 was abandoned and grouted. A portland cement slurry was placed ' into the augers and then cement was tremmied into the soil boring from the total depth to the surface. Soil boring B9 was single-completed as ground water monitoring well MW-9,utilizing schedule 40, ' 2-inch diameter, perforated polyvinylchloride (PVC) well casing (0.020-inch slot) screened from 70 to 75 feet bsg and 2-inch diameter blank PVC well casing extending to the surface. ' Soil boring B10 was single-completed as ground water monitoring well MW-10, utilizing schedule 40, 2-inch diameter,perforated PVC well casing(0.020-inch slot) screened from 55 to 60 feet bsg and 2-inch diameter blank PVC well casing extending to the surface. ; Each well was installed bYp g lacin a PVC well casing assembly through the hollow stem of the augers to the total depth of the boring. The,augers were incrementally raised as No. 2112 Lonestar ' Lapis Luster 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 ' filter pack placement, a surge block was inserted into the well casing and was alternately raised and lowered(surged)repeatedly for approximately 20 minutes.Bentonite chips(annular seal)or coated bentonite pellets were placed above the filter pack and were hydrated with clean tap water. Two feet of seal was installed over the shallow monitoring wells to avoid portland cement intrusion into the filter pack. The remaining annular space was backfilled near to the surface grade with portland cement(grout seal). As-built monitoring well-construction diagrams are included as Appendix A. ' 2.5. WELL DEVELOPMENT On 21 March 2002, the newly installed monitoring wells were developed. An inertial bailer was utilized to remove sediment settled at the bottom of each well casing. Subsequently, the ground water was purged from each monitoring well utilizing a Waterra pump until ground water was visually sediment free;approximately 60 gallons of water were removed from each monitoring well. ' Purged ground water was containerized in properly labeled DOT-approved model 17H 55-gallon drums and was stored'on-site in an area lacking public access. Monitoring well field logs for well developmental activities are included in Appendix B. 1 ' Advanced GeolEnvironmental,Inc.