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Mr.Bob Gondek C A M B R I A March 11, 2004 appeared to be ongoing as evidenced by oil leaching from the test pit sidewalls. Photographs 10 and 11 show the easternmost pit. All test pits were backfilled with native soils to protect site personnel from the risks of an open excavation. Pipeline Easement Assessment: On December 15, 2003,Cambria collected samples PLl through PL6 along the exposed trench bottom to characterize soils beneath the pipeline. Photographs 4 and 12 show the exhumed pipeline and open trench. Samples were collected by scraping approximately 6 inches of soil from the sample location then driving a new brass sleeve into the exposed soil. Sample locations are shown on Figure 2. Soil samples were analyzed for TPH in the © gasoline range (CQ- C12) and TPH extended range (C13 - C40) by EPA Method 8015M, and for BTEX by EPA Method 8021. Soil sample P3-5' collected from the trench bottom immediately beneath the pipeline rupture point contained 3,900 mg/kg TPH(C4-C12), 21,000 mg/kg TPH(C13 - Cao),<50 mg/kg benzene, 75 mg/kg toluene, 22 mg/kg ethylbenzene, and 130 mg/kg xylenes. In the five remaining soil samples no TPH (Ca- C12) or BTEX were detected and TPH (C13 - C40) ranged from 26 to 54 mg/kg, indicating a relatively limited extent of oil impact along the pipeline. These results also suggest that no other pipeline leaks had occurred at the Site in the past. Soil sample results are summarized in Table 1 and the analytical laboratory reports are included as Attachment D. Interim Remedial Actions CPL and Cambria directed the emergency response crews in recovering and/or containing all free-flowing crude oil that posed a risk of migration, to the degree that soil excavation was feasible and safe. Within 24 hours of the initial release, oil in the areas characterized by the test pits had already infiltrated to between depths of 5 and 9 ft bgs. Due to the depth of impact, excavation of all oil-saturated soil was not feasible without appropriate planning including health and safety engineering. Instead, Cambria directed excavation and stockpiling of surfrcial soils to eliminate oil puddles and oil-saturated soils that could contribute to soil pore pressure and drive vertical migration. Surface Soils Excavation: On December 6,2003,Cambria directed excavation and stockpiling of oil-saturated soil and areas with residual standing oil. The affected areas were scraped to between 0.5 and 2 ft bgs. Figure 3 and Photographs 13 through 15 show the areas scraped to help limit crude oil migration. Cambria estimates that approximately 600 to 800 cubic yards of soil were excavated and stockpiled as part of this effort. Receiving Pit Over-Excavation: The receiving pit had been used to collect oil accumulating near the rupture point. As a result, the floor and sidewalls of the pit were impacted by oil. On December 6, 2003, after evacuating all oil, the receiving pit was over-excavated and the oil- impacted soils were stockpiled onsite. Cambria directed over-excavation to remove all visually 5