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Ms. Anne Connor March 9, 2007 Page 3 Preliminary Activities and Utility Survey �-� On February 6, 2007, SECOR marked the work area in white paint and notified Underground Service Alert, which issued dig ticket number 046933 for the excavation work. On February 9, 2007, SECOR met with Cruz Brothers Locators, a private utility locating firm, to confirm that the work area was clear of subsurface utilities and/or obstructions. The Ione subsurface utility identified in the vicinity of the work area was an electrical line located adjacent to the fence fronting East French Camp Road. The location of this electrical line, `-' assumed to be part of the electric gate and vehicle sensor mechanism, did not conflict with the proposed excavation area. Prior to mobilizing for the excavation work, SECOR prepared a Site-specific health and safety plan (HASP) describing safety procedures for each aspect of the field work. The HASP included emergency contact information, potential chemical and physical hazards, `J methods for monitoring, chemical action levels, and response actions. SECOR employees and subcontractors reviewed the HASP prior to the start of each work day and before returning to work after the mid-day lunch break. U Excavation and Sampling Activities On February 12, 2007, SECOR mobilized to the Site to perform the excavation oversight and confirmation sampling. SECOR contracted with Engineering Resource/Remediation Group (ERRG) to perform the excavation and backfill work. Following the health and safety tailgate meeting, ERRG began to excavate in the vicinity of the previous HA-5 soil boring location. The excavation was extended to approximately 2 feet bgs, and excavated soils were examined visually and screened with a photoionization detector (PID) to detect evidence of petroleum hydrocarbon impact. Excavated soils were placed into two 20-yard bins provided by PTS on behalf of PG&E. Shallow soils in the initial excavation area did not exhibit evidence of chemical impact. However, as the excavation was extended to the east (towards the interior of the property), SECOR encountered discolored soils with a petroleum hydrocarbon odor. When screened for volatile vapors, these soils generated elevated readings on the PID. The excavation was extended towards the adjacent paved driveway, where digging was halted to avoid undermining the pavement. The excavation was then extended to the northeast, towards `-' the heavy equipment storage shed, to a depth of 4 to 6 feet bgs. All soils in this area deeper than approximately 3 feet bgs exhibited evidence of chemical impact from petroleum hydrocarbons (discoloration, odor, and elevated PID readings). In order to U investigate the vertical extent of chemical impact, a small `test pit' was excavated to I:\PG&E\French Camp\2007 Investigation\report\Excavation Report_Final.doc March 9,2007 Project No.050T.50351.00.0003 v