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24 June 2008 <br /> AGE-NC Project No. 05-1286 <br /> Page 3 of 7 <br /> 3.1.2. Soil Collection and Characterization <br /> For pilot boring EW-1113,EW-12B and MW-13B,soil samples were collected ahead of the drillbit <br /> using a California modified split-spoon sampler.The samples were collected continuously at 18-inch <br /> intervals,beginning at 60 feet bsg and terminating at 80 feet bsg utilizing a 140-pound hammer to <br /> advance the sampler. <br /> After sample recovery,the split-spoon sampler was opened and the collected soil carefully removed <br /> and placed on clean plastic sheeting for characterization.The soil was visually classified on a boring <br /> log in accordance with the Unified Soil Classification System. The soil boring logs are provided in <br /> Appendix C. <br /> All augers were pressure cleaned prior to use to avoid cross-contamination.The sampling equipment <br /> was washed in an Alconox solution and rinsed with water.Drill cuttings generated by drilling were <br /> containerized in two 20 cubic yardbins,temporarily stored on-site until proper disposal was arranged <br /> (Section 3.6.). <br /> 3.1.3. Monitoring Well Completion <br /> Pilot borings EW-11B and EW-12B were completed as groundwater extraction wells utilizing 5 feet <br /> of 6-inch diameter stainless steel (SS312) blank casing from 80 to 85 feet bsg; 20 feet of 6-inch <br /> diameter stainless steel (SS304) 0.010-inch circumslot screen from 60 to 80 feet bsg and 6-inch <br /> diameter schedule 80 polyvinylchloride (PVC) blank casing from 0 to 60 feet bsg. Number 2/12 <br /> Lonestar sand was installed from 58 to 85 feet bsg. A 2-foot bentonite pellet (TR30) plug was <br /> installed above the filter pack and hydrated for 30 minutes. The well was then grouted to near- <br /> surface with type MI portland cement, and a water-tight, 2-foot square traffic-rated well box was <br /> installed over each well. <br /> Pilot borings IW-BH1 and IW-BH2A were completed as groundwater injection wells utilizing 20 <br /> feet of 6-inch diameter schedule 80 PVC 0.040-inch slotted well screen from 60 to 80 feet bsg and <br /> 6-inch diameter schedule 80 PVC blank casing from 0 to 60 feet bsg. Medium aquarium sand was <br /> installed from 58 to 80 feet bsg. A 2-foot(IW-BH2A)or 4-foot(IW-BH1)bentonite pellet(TR30) <br /> plug was installed above the filter pack and hydrated for 30 minutes. The well was then grouted to <br /> near-surface with type I/II portland cement, and a water-tight, 2-foot square traffic-rated well box <br /> was installed over each well. <br /> Pilot boring MW-13B was completed as a groundwater monitoring well utilizing 20 feet of 2-inch <br /> diameter schedule 40 PVC 0.010-inch slotted well screen from 60 to 80 feet bsg and 2-inch diameter <br /> schedule 80 PVC blank casing from 0 to 60 feet bsg.Number 2/12 Lonestar sand was installed from <br /> Advanced GeoEnvironmental,Inc. <br />