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H 17 April 2003 AGE-NC Project No 97-0333 ' Page 4of7 and 65 feet bsg(upper Second Zone), 85 and 90 feet bsg(lower Second Zone), 115 and 120 feet bsg (Third Zone), 140 and 145 feet bsg (Primary Aquifer Zone) and between 165 and 170 feet bsg (Primary Aquifer Zone) Each screen interval consisted of drilling3/8-inch diameter holes at regular intervals, wrapping each 3/8-inch diameter hole with a stainless steel, 0 02-inch mesh screen and securing the mesh screen with stainless steel locking clamps ' After deploying the multi-level well casing in the hollow stem boring to total depth, filter pack material consisting of pre-washed #3 Lonestar sand was added through the hollow stem augers to approximately two feet above each screened interval A bentonite seal(coated bentonite pellets)was ' placed between each filter pack interval to minimize the potential for cross contamination into the screened section of the well Each bentonite seal was formed by pouring coated bentonite pellets into the annulus and allowing them to settle (hydrate) on the filter pack The remaining annular space ' above the uppermost screen interval and bentonite seal was filled to 1-foot bsg with a portland type cement grout The grout mixture consisted of Type 1/II portland neat cement Water-tight, traffic- rated well boxes were then installed over the wells utilizing a neat cement The top view of wells ' MW-7 through MW-13 are depicted in Figures 6 through 12, respectively, for the screen interval locations relative to a reference mark located in"Interval A", well construction details for MW-7 • through MW-13 are depicted in Figures 13 through 19, respectively 25 WELL DEVELOPMENT ACTIVITIES On 21 October and 01 November 2002, wells MW-7 through MW-13 were developed by lowering and raising(surging) a 3/8-inch outer diameter, length-discrete polyethylene hose equipped with a ball-valve water tip through each specific water-charged screened section A Watera-Hydro-Lift R pump equipped with a mechanical arm was utilized to surge the polyethylene hose Prior to well development, depth to water and total depth measurements were collected from each screened interval utilizing a Solinst water level indicator Thereafter, ground water was evacuated ' (purged)from the bottom of each monitoring well screened interval until ground water was visually sediment free Approximately 0 5 to 5 gallons of water were purged from the multi-level monitoring wells during development Temperature,pH and conductivity of purged ground water were measured at regular intervals utilizing an ICM water analyzer Purged ground water was contamenzed at the site in properly labeled DOT-approved model 17H 55-gallon drums Copies of monitoring well field logs for development activities are in Appendix C t • Advanced GeoEnvironmental,Inc