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I ' 13 May 2003 . AGE-NC Project No 95-0173 ' Page 4 of 6 ' 3 5 MONITORING WELL COMPLETION Soil boring MW-13 (A-C) was completed as a ground water monitoring well utilizing 1 7-inch ' diameter continuous polyethylene multichannel tubing(CMT) The inside of the CMT consisted of seven%2-inch diameter chambers(Figure 4),AGE utilized six of the seven multi-level chambers and installed two screen intervals at depths between 95 and 100 feet bsg(Hydrologic Unit 5),two screen ' Intervals between 120 and 125 feet bsg (Hydrologic Unit 7) and two screen intervals between 145 and 150 feet bsg (Hydrologic Unit 9) Each screen Interval consisted of drilling 3/8-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 Imaterial consisting of pre-washed #3 Lonestar sand was added through the hollow stem augers to approximately the upper-most level of each screened interval A bentonite seal (coated bentonite pellets) was placed between each filter pack interval to minimize the potential for cross Icontamination 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 I 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 I/H portland neat cement Water-tight,traffic-rated well boxes were then installed over the wells utilizing neat cement A figure I depicting the top-view of well MW-13 (A-C) is depicted in Figures 4 and includes each screen interval location relative to a reference mark located in "Interval A", well construction details for MW-13 (A-C) are depicted In Figure 5 I 36 WELL DEVELOPMENT ACTIVITIES On 05 November 2002, depth to water and total depth measurements were collected from each screened interval of well MW 13 (A-C)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 by lowering and raising(surging)a 3/8-inch outer diameter, length-discrete polyethylene hose equipped with a ball-valve water tip through the water-charged Iscreened section,a Watera-Hydro-Lift H pump equipped with a mechanical arm was utilized to surge the polyethylene hose An estimated 2 to 4 gallons of ground water was purged from the multi-level monitoring well during well development Temperature,pH and conductivity of purged groundwater were measured at regular intervals utilizing an Oakton water analyzer Purged ground water was containenzed 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 IAdvanced GeoEnviron mental,Inc