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I 30 September 2005 • AGE-NC Project No 97-0333 IPage 4 of 6 ' chambers and installed screen intervals at depths generally between 14 and 25 feet bsg(Hydrologic Unit 1),39 and 45 feet bsg(Hydrologic Unit 2), 69 and 75 feet bsg(Hydrologic Unit 3),94 and 100 feet bsg (Hydrologic Unit 4), 119 and 125 feet bsg (Hydrologic Unit 5) and between 144 and 150 ' feet bsg (Hydrologic Unit 6) Each screen interval consisted of drilling 3/s-inch diameter holes at regular intervals,wrapping each 3/9-inch diameter hole with a stainless steel,0 0045 wire screen or 100 mesh screen and securing the mesh screen with stainless steel locking clamps ' After deploying the multi-level well casing down the hollow core barrel drill assembly to total depth, filter pack material consisting of pre-washed 43 Lonestar sand was added through the hollow drive rods to approximately one foot above each screened interval Thereafter, a bentonite seal (coated bentonite pellets)was placed between each filter pack interval/well screen 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,filter pack interval and bentonite seal interval was filled to 2-foot bsg with Volclay Twelve-inch diameter,water-tight, I traffic-rated well boxes were then installed over the wells utilizing a neat cement The top view of wells MW-13 through MW-15 are depicted in Figures 3 through 5, respectively, for the screen interval locations relative to a reference mark located in"Interval A", well construction details for MW-13 through MW-15 are depicted in Figures 6 through 8, respectively 25 WELL DEVELOPMENT ACTIVITIES I On 15 and 19 July 2005, depth to water and total depth measurements were collected from each screened interval of wells MW-13 through MW-15 utilizing a Solinst water Ievel 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 screened section,a Watera-Hydro-Lift II pump equipped with a mechanical arm was ' utilized to surge the polyethylene hose Approximately 11/z to 15 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 Oakton water analyzer Purged ground water was containerized 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 D 26 WELL ELEVATION SURVEY On 28 September 2005, a California state-licensed survey engineer from Baumbach& Piazza Inc (BP) surveyed a reference point on the casing top of wells MW-13 through MW-15 to the nearest Advanced GeoEwnronmental,Inc I