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WORK PLAN Prior to scheduling on-site work activities USA Dig will be contacted, per county requirements, to identify any underground utilities that may interfere with excavation though it is our understanding that USA Dig will only identify utilities located on public lands, easements or right-of-ways not private property. Prior to commencing work we will verify there are no remaining fluids in the tank. Once that has been verified, a minimum of 20 pounds of dry ice will be placed in the tank and let stand for a minimum of 30 minutes to purge any air from the tank and render it non-combustible. A portable LEL meter will be used to verify this condition. Overburden soils will then be excavated and stockpiled separately from other soils on site. The tank will then be removed and immediately placed upon a licensed Hazardous Waste Transport vehicle for off-site cleaning and scrapping at an approved facility. Soil samples will then be collected from 24" below the tank setting following San Joaquin County EHD sampling protocol. Sampling will be performed by persons under the supervision of a State Registered Geologist following established sampling protocol. Soil samples will be analysed at a state certified lab for the following : VOC's by EPA 8010/8020, TPHG, TPHD, PCB's, and the Heavy Metals, Cadmium, Chromium, Chromium VI, Lead, Nickel and Zinc. Excavation will continue until all soils that are visually contaminated are removed. Contaminated soils will be stockpiled on site. Soils will be stockpiled on paved portions of the facility if possible. If it becomes necessary to stockpile soils elsewhere on site, a layer of 6 mil visqueen will underly the contaminated soils. Once confirmatory sampling has indicated that the site has been sufficiently remediated the excavation will be backfilled with imported engineered backfill materials suitable to achieve greater than 90% relative compaction. The contaminated soils stockpiled on site will then be prepared for bioremediation or off- site ffsite disposal whichever is deemed the most cost effective. Non-bioremediated soils will be removed to an appropriately approved off-site disposal facility after stockpile sampling necessary for proper characterization has been completed. A final report documenting and summarizing all remediation activities will be submitted to San Joaquin County Environmental Health Department within 90 days of completion of all on site work.