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Former Discovery Chevrolet September 16, 1998 Trac California CReport on Remedial Work work was conducted in August 1998 utilizing Horizon Field Methods and Procedures (included as Attachment B), and in accordance with the Site Safety Plan (Horizon, August 5, 1998). Soil excavation work was performed by Nave Brothers Construction (Nave Bros.) of Corcoran, California. Overexcavation and Soil Sampling Beginning on August 10, 1998, Horizon and Nave Bros. personnel were onsite to begin overexcavation activities at the site. The excavation work was performed by a steel-tracked excavator accompanied by a rubber-tired loader. Removal of the asphalt and concrete slabs in the area indicated on the Excavation Plan revealed a thin layer of gravelly sand fill underlain by native soil and fill materials. The native soil and fill materials consisted predominantly of grayish-brown to blue-gray sandy clay to the maximum depth of the . excavation at approximately 12 feet below surface grade (bsg). Groundwater was r encountered in the excavation at a depth of approximately 11 feet bsg. L The excavated soil was screened for hydrocarbons with a photionization meter (P )ID . The results of the field screening with the PID indicated that the majority of the soil was r impacted with gasoline hydrocarbons beginning at a depth of '/z-foot bsg and extending L down to the surface of the groundwater at a depth of approximately 11 feet bsg. The excavated soil was temporarily stockpiled to the north of the excavation at the site. During El the overexcavation operations, a temporary construction fence was placed around the excavation for safety reasons. EOn August 11, groundwater monitoring well MW-1, located on the southern side of the former tank pit was destroyed during the excavation operations. The 2-inch diameter PVC well casing was exposed during the excavation operations, then pulled and removed by the excavator. Also on August 11, two preliminary characterization soil samples were collected from the north (S-9%-N SW) and east (S-10-E SW) sidewalls of the excavation to evaluate for gasoline hydrocarbons at the approximate proposed lateral extents of the excavation. On August 13, soil samples were collected from the sidewalls (S-0813-TPN, S-0813-TPE, S-0813-TPS and S-0813-TPW) and floor (S-0813-TPB) of the completed excavation at the locations selected by Mr. Jeff Wong, Hazardous Materials Trainee for the SJCPHS-EHD, as shown on the Excavation Plan. The soil samples were collected to evaluate for gasoline Ehydrocarbons at the proposed lateral extents of the excavation. At the direction of Mr. Ron Rowe, Registered Environmental Health Specialist (R.E.H.S.) at the SJCPHS-EHD, the sidewall soil samples were collected approximately 1% to 2 feet into the sidewalls at the Eselected depths ranging between approximately 8'/z to 11 feet bsg, while the soil sample from the floor of the excavation was collected at a depth of approximately 12 feet bsg, which was below the static groundwater level. Upon arrival of soil at the ground surface in the excavator bucket, each of the soil samples was then collected by driving Iaboratory-cleaned brass sleeves into the soil in the excavator bucket. Mr. Jeff Wong of the SJCPHS-EHD EROV witnessed the collection procedures for the five soil samples collected from the excavation. C3001-21.ovx 2 HORIZON ENVIRONMENTAL INC.