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31 October 2002 AGE-NC Project No. 96-0254 Page 6 of 7 4.3. EXCAVATION SOIL SAMPLING Soil samples collected from the base and sidewalls of the excavation will be obtained using a backhoe or excavator. Soil samples will be collected from the bucket of the excavating equipment by pressing a 3-inch long by 2-inch diameter brass sleeve into the excavated soil material. The exposed ends of the sample sleeve will be covered with Teflon sheets,capped and sealed with tape. Soil samples will be collected from soil stockpiles by digging approximately one foot into the soil stockpile. Soil samples will be collected by hand sampling methods using a stainless steel or carbon steel trowel, or by pressing a brass sampling sleeve into the soil stockpile. Following sample collection,each sample sleeve will be properly preserved as described above and will be labeled with the boring location,depth,time,date and sampler's initials.Appropriately sealed and labeled samples will be placed in a chilled container under ice and transported under chain-of- custody procedure to aDHS-certified laboratory. 4.4. SOIL BORING/MONITORING WELL INSTALLATION To install replacement wells MW-1B, MW-4 and MW-7, t hree monitoring well pilot borings will be advanced utilizing a truck-mounted drill rig equipped with either 8.25-inch hollow stem auger. The pilot borings will be advanced near the current locations of MW-1B, MW-4 and MW-7. 4.4.1 Monitoring Well Installation Following advancment of the pilot borings, 2-inch diameter Schedule 40 PVC 0.010-inch slotted well screen and casing will be installed through the interior of the hollow-stem augers. A 10-foot section of well screen will be placed from approximately 5 feet bsg to 15 feet bsg in wells MW-1B and MW-4; a 5-foot section of well screen will be placed from approximately 42 feet bsg to 47 feet bsg in well MW-7. After installing the well casing, filter pack material consisting of pre-washed#2/12 Lonestar sand will be added from the bottom of theborehole to approximately two feet above the screened interval. Following placement of the filter pack, the well will be surged to assist in settling the filter pack; additional sand will be added if settling occurs. A nominal two-foot thick bentonite seal will be placed above the filter pack in wells MW-1B and MW-4 to minimize the potential of grout penetration into the filter pack or screened section of the well;anominal four-foot thick bentonite seal will be placed above the filter pack in well MW-7.The Advanced GeoEnvironmental,Inc.