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1 ' 10 May 2004 . AGE-NC Project No 96-0229 ' Page 4 of 8 ' 2 3 EQUIPMENT DECONTAMINATION The hollow stem augers were steam cleaned prior to each bore hole advancement The split-spoon I sampler and brass sleeves used for sample collection were pre-washed with a solution of Alconox, and were rinsed with clean tap water prior to each sampling sequence Rinseate generated from decontaminating the equipment was placed in properly labeled Department of Transportation(DOT)- approved model 17H 55-gallon drums and was stored on-site in an area lacking public access ' 2 4 MONITORING WELL COMPLETION Soil borings MW-13 through MW-19 were completed as ground water monitoring wells utilizing ' 1 7-inch diameter continuous multi-channel (CMT) or mute-level polyethylene well casing The Inside of the multi-level well casing consisted of seven 1/z--inch diameter teflon chambers,generally, screen intervals were installed at each well at depths between 3 5 and 40 feet bsg(First Water Zone), ' between 62 and 67 feet bsg(First Confining Unit),between 79 and 84 feet bsg(Second Water Zone), between 95 and 100 feet bsg (Second Confining Unit) and between 120 and 125 feet bsg (Third • Water Zone) Each screen interval consisted of drilling a total of three 3/8-inch diameter holes(ports) at regularly spaced intervals (18-inch apart), wrapping each 3/9-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 I approximately one foot above and one foot below 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 through the hollow stem augers,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 approximately 1-foot bsg with a portland type cement grout, the grout mixture consisted of Type I/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-13 through MW-19 are depicted in Figures 5 through 11,respectively,for each screen interval location relative to areference mark located in shallowest-screened well"A",as-built well construction details for MW-13 through MW-19 are depicted in Figures 12 through 18, respectively 25 WELL DEVELOPMENT ACTIVITIES On 04 August and 24 October 2003,wells MW-13 through MW-19 were developed by lowering and . raising(surging) a3/8-inch outer diameter, length-discrete polyethylene hose equipped with a ball- Advanced GeoE'nvironnnental,Inc I