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Mr. Marshall Cloud August 15, 2006 Page 2 Record of Decision DDJC-Sharpe's Operable Unit#2 (OU2) Record of Decision (ROD) remedy for lead and chromium-contaminated soil specified excavation and disposal of soil exceeding the United States Environmental Protection Agency's 2004 Industrial Preliminary Remediation Goal cleanup levels of 800 mg/kg and 300 mg/kg for lead and total chromium, respectively. The OU2 ROD specifies confirmation sampling of the excavation base to ensure soils with lead and chromium concentrations above the cleanup levels have been removed to a minimum depth of two feet below the existing ground surface (bgs). Sampling and Analysis Approximately 1,170 square feet of Site 26 Area 6 will be excavated to a depth of approximately two feet bgs. The excavated dirt will be collected in roll-off bins where each bin will be individually characterized for off-site disposal. After two feet of soil is removed, the exposed subsurface will be sampled to determine the vertical extent of any remaining contamination. The samples of the excavation floor will be collected on a grid pattern of approximately 30 by 30 linear feet. Soil samples will be collected via hand auger or Shelby tube method. All samples from the excavation floor will be analyzed for total lead and chromium using Method SW601013. Analytical results will determine whether additional excavation is needed, according to the Work Plan's Soil Characterization Flow Diagram. If over-excavation is required, an additional one foot of soil will be removed from those cells exceeding the cleanup standards with floor samples being collected and analyzed again. The process will be repeated until the cleanup standards are achieved. The excavation will be restored to pre-existing grade with certified clean fill after confirming that cleanup standards are met for lead and chromium. Conclusion DTSC concurs with the Work Plan's determinations and proposed soil removal action. DTSC will be awaiting a mobilization notice from DDJC-Sharpe so it may attend and provide regulatory oversight during the upcoming fieldwork.