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t. V 01 December 2006 AGE-NC Project No. 98-0440 Page 3 of 6 Lo 2.5. DISPOSAL OF HYDROCARBON-IMPACTED SOIL �-Z'CA On 01 June 2006,approximatel700 ns of petroleum hydrocarbon-impacted soil was transported to Forward Landfill in Manteca, alifornia for disposal. Landfill weight tags are included as Appendix B. 2.6. MONITORING WELL INSTALLATION On 26 September 2006, monitoring wells MW-1 and MW-2 were reinstalled as MW-IA and v MW-2A,their locations are shown on Figure 2.Pilot borings were advanced using an CME 75-LAR equipped with 8.25-inch augers. The pilot borings for MW-IA and MW-2A were advanced to approximately 24 feet bsg; soil samples were collected from MW-2A at 5-foot intervals beginning th- at 5 feet bsg. The drill rig and two-man crew were supplied by Cascade Drilling,Inc. Auger returns generated by drilling were stored in properly labeled DOT-approved model 17H 55-gallon drums pending laboratory analysis. The wells were completed as ground water monitoring wells utilizing 2-inch PVC casing with 0.020-inch slotted screen installed from approximately 4 to 24 feet bsg. Blank casing was utilized from the top of the screened-interval to surface grade for each well. The filter pack(No. 2112 sand) was installed from total depth to approximately 3 feet above the screened interval of each well. A nominal 2-foot bentonite chip plug was installed above the filter pack in wells MW-IA and MW-2A. `r The bentonite chip plug was allowed to hydrate for approximately 30 minutes.Following installation of the bentonite plug, the wells were then grouted to near surface grade with portland cement. L. Water-tight,traffic-rated well boxes were then installed over the wells. As-built well diagrams are depicted on the boring logs in Appendix C. 3.4. FINDINGS .. A discussion of laboratory and field results of soil samples collected during excavation procedures as well as an estimated total mass of hydrocarbons removed is detailed below. 3.1. ANALYTICAL RESULTS OF SOIL SAMPLES +- Seven soil samples were collected from the sidewalls (face) and floor of the excavation. Samples were collected from the North Face(NF)-14,South Face(SF)-15,East Face(EF)-15,Bottom(B)-16, Bottom North(BN)-16,Bottom South(BS)-16 and west-wall Concrete Bay(CB)-14(Figure 2).One composite soil sample (SP 5-9) was analyzed from the soil stockpile generated during excavation Advanced GeoEnvironmental,Inc.