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Draft Diesel Impacted Soil Removal Report May 2010 California Army National Guard Armory Lodi, CA the diesel contaminated soil at the site. The SJCEHD has subsequently referred oversight to the CVRWQCB. On January 28,2010, OTIE collected pre-characterization and waste characterization soil samples at depths ranging from 12 to 40 inches below ground surface(bgs) from within the visibly stained area and up to 2 feet outside that area. The samples were analyzed for Total Petroleum Hydrocarbons as Diesel Fuel(TPH-D)by gas chromatography(GC)using United States Environmental Protection Agency(EPA) Method 8015B. Consistent with the strategy addressed in the Workplan,a threshold of 100 milligrams per kilogram(mg/kg)was used as a cleanup goal for TPH-D. Additionally,the waste characterization sample was analyzed for a variety of other constituents to profile the soil for disposal at a Class II nonhazardous waste impoundment. On April 2,2010, and based on pre-characterization soil sampling results, OTIE mobilized to the site to oversee excavation of diesel fuel impacted soils and site restoration with clean fill. Sequoia Construction (Sequoia), a licensed excavation contractor,provided excavation and restoration services under subcontract to OTIE, and excavated an area approximately 10 feet wide by 10 feet long by 3 feet deep within the general footprint of the area previously covered with plastic and identified as potentially impacted(based on pre-characterization soil sampling results). Sequoia loaded excavated soils directly into an end-dump truck for purposes of off-site transportation and disposal. Of the six confirmation samples collected following excavation, one sample slightly exceeded the 100 mg/kg default cleanup threshold. In consideration of the majority of analytical results of soil samples collected from the excavation, evaluated with the screening levels established by the San Francisco Bay Regional Water Quality Control Board(SFRWCB), site and regional groundwater conditions as applicable mitigating factors, OTIE concludes that the soil removal actions at the site were completed in substantial accordance with the strategy defined in the CVRWQCB-approved Workplan,that soil removal and site restoration actions at the site were effective in meeting project objectives in accordance with the SJCEHD September 30,2009 Notice to Abate Immediately, and that a finding of NFA is supported. Based on the findings and conclusions presented in this report, OTIE respectfully recommends the site be given final closure and requests a final NFA letter be provided to the CA ARNG by the CVRWQCB as the lead regulatory agency,or by the SJCEHD as the local oversight authority.