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' 11 June 2001 AGE-NC Project No. 96-0232 Page 9 of I 1 ' diameter hollow-stem augers. Cuttings generated during drilling will be placed on plastic sheeting and covered.Rinseate will be containerized in properly labeled DOT-approved 55-gallon drums, and stored on-site in an area lacking public access. Disposal alternatives will be evaluated based on ' results of soil and water analysis. ' 4.2. WELL COMPLETION Each soil boring will be completed as a multi-level ground water monitoring well utilizing 1.7-inch ' diameter polyethylene(outer)tubing. The inner tubing consists of multiple %z-inch diameter teflon tubes partitioned into separate chambers. A stainless steel, 0.02-inch screen will be wrapped around each perforated area of the tubing. Additional multi-level design literature is contained in Appendix A. After deploying the multi-level well casing in the hollow stem boring, a filter pack material consisting of pre-washed#212 Lonestar sand will be added through the augers to approximately two feet above each screened interval. A bentonite seal(pell plug-coded bentonite pellets)will be placed between filter pack intervals to minimize the potential for cross contamination into the screened section of the well. The bentonite seal will be formed by pouring bentonite pellets into the annulus and allowing them to settle on the filter pack. The remaining annular space from the uppermost screen interval and bentonite seal will be filled to the ground surface with a portland cement grout. The grout mixture will consist of Type III portland neat cement and not more than 6 gallons of water per 94-pound sack of cement. The grout will be placed by pumping through tremmie pipe. A proposed well construction diagram is depicted in Figure 6. The grout will be placed by pumping through tremmie pipe. A grouting inspection will be scheduled with PHS-EHD personnel. 4.3. WELL DEVELOPMENT Development of the proposed wells will consist of a combination of bailing with a%-inch teflon tube bailer to remove the major portion of fine-grained sediment from inside the well and additional ground water evacuation (purging) with a peristaltic pump to finish the removal of fine-grained ' sediment. Developmental purging activities will be continued until field parameter(pH, electrical conductivity, and temperature)readings have stabilized and purged water is visually sediment-free. 4.4. EQUIPMENT DECONTAMINATION All down-hole drilling and sampling equipment will be pressure washed prior to starting each boring. Advanced GeoEnvironmental,Inc.