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1 <br /> ' 24 March 2004 <br /> • AGE-NC Project No 97-0301 <br /> Page 4 of 7 <br /> I <br /> between 35 and 45 feet bsg(First Water Zone),65 and 75 feet bsg(Second Water Zone),95 and 100 <br /> ' feet bsg(Third Water Zone), and between 120 and 125 feet bsg (Fourth Water Zone) Each screen <br /> Interval consisted of drilling a total of three %-mch diameter holes (ports) at regularly spaced <br /> Intervals(18-Inch apart),wrapping each 3/8-inch diameter hole with a stainless steel,0 02-inch mesh <br /> screen and securing the mesh screen with stainless steel locking clamps <br /> After deploying the multi-level well casing In the hollow stem boring to total depth, filter pack <br /> ' material consisting of pre-washed #3 Lonestar sand was added through the hollow stem augers to <br /> approximately two foot above and one foot below each screened Interval A bentonite seal (coated <br /> ' bentonite pellets)was placed between each filter pack interval to minimize the potential for cross <br /> contamination Into the screened section of the well Each bentonite seal was formed by pouring <br /> coated bentonite pellets through the hollow stem augers,into the annulus and allowing them to settle <br /> ' (hydrate) on the filter pack The remaining annular space above the uppermost screen Interval and <br /> bentonite seal was filled to approximately 1-foot bsg with a portland type cement grout, the grout <br /> mixture consisted of Type 1/11 portland neat cement Water-tight,traffic-rated well boxes were then <br /> Installed over the wells utilizing a neat cement The top view of wells MW-8 through MW-12 are <br /> depicted in Figures 5 through 9,respectively,for each screen interval location relative to a reference <br /> mark located in shallowest-screened well"A", as-built well construction details for MW-8 through <br /> • MW-12 are depicted in Figures 10 through 14,respectively <br /> ' 25 WELL DEVELOPMENT ACTIVITIES <br /> On 18 July and 09 September 2003,wells MW-8 through MW-12 were developed by lowering and <br /> ' raising (surging) a 3/8-inch outer diameter, length-discrete polyethylene hose equipped with a ball- <br /> valve water tip through each specific water-charged screened section A Watera-Hydro-Lift H pump <br /> ' equipped with a mechamcal arm was utilized to surge the polyethylene hose <br /> Prior to well development, depth to water and total depth measurements were collected from each <br /> ' screened interval utilizing a Solinst water level indicator Thereafter, ground water was evacuated <br /> (purged)from the bottom of each monitoring well screened interval until ground water was visually <br /> sediment free Approximately 0 25 to 10 gallons of water were purged from the multi-level <br /> ' monitoring wells during development Temperature,pH and conductivity of purged ground water <br /> were measured at regular intervals utilizing an Oakton water analyzer Purged ground water was <br /> contamenzed at the site in properly labeled DOT-approved model 17H 55-gallon drums Copies of <br /> ' monitoring well field logs for development activities are In Appendix C <br /> 1 <br /> ' Advanced GeoEnvironmental,Inc <br />