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• Work Plan For Soil Sampling-Tosco(Former Unocal)#6981,4707 Pacific Avenue, Stockton, CA March 7, 2000 product lines will be analyzed for Total Petroleum Hydrocarbons as gasoline (TPHg) by EPA Method 8015/DHS LUFT, for benzene,toluene, ethylbenzene, and total xylenes(BTEX)by EPA Method 8020, and total lead by EPA Method 6010. Selected soil samples will be analyzed for the fuel oxygenates methyl tert-butyl ether(MTBE), tert-butyl alcohol, (TBA), di-isopropyl ether (DIPE), ethyl tert-butyl ether(ETBE), and tert-amyl methyl ether(TAME)by EPA Method 8260. Task 2. Management of Excavated Soil and Limited Over-Excavation If soils saturated with hydrocarbons are encountered, limited over-excavation of the impacted soil may be performed. Over-excavation, if performed, will be limited to approximately 1,000 cubic yards of soil. The vertical extent of the over-excavation will be based on the depth to groundwater (expected to be approximately 25 feet bgs) and the limits of the excavation equipment, which is approximately 25 feet. GR will observe the excavation activities. Confirmation soil samples will be collected from the base and lateral limits of the excavation and analyses performed in accordance with SJCPHS-EHD guidelines. Soil removed during over-excavation activities will be stockpiled at the site in the manner described above, pending disposal. Task 3. Groundwater Sampling Contingency We do not anticipate that excavation will continue deeper than groundwater (expected at a,p, _;r_te!y 25 feet bgs), and therefore do not anticipate the need to pump water from the excavation. However,should groundwater be encountered in the excavation,one groundwater grab sample will be collected. The grab sample will be collected after the excavation has been evacuated one time and allowed to sufficiently recharge. The groundwater grab sample will be submitted under chain-of-custody documentation to Sequoia Analytical for analysis as described above for excavated soils.. Task 4. Disposal of Excavated Soil Stockpiled soil will be removed from the site and disposed of at the Forward landfill in Manteca, CA. Samples from the stockpiled soil will be collected and analyzed in accordance with Forward's requirements. We anticipate that it will take a maximum of 2 weeks to receive analytical results, profile the stockpile for landfill acceptance,and arrange for transportation to haul the stockpile to the landfill. However,due to the site's location near a major street intersection, its proximity to a Target retail establishment, and to reduce the potential hazard associated with the presence of stockpiled soil onsite generated from excavation activities, Tosco requests SJCPHS-EHD written approval to transport the soil to Forward Landfill's holding area. Once analytical results of the stockpile sampling are received,the landfill will properly dispose of the soil at their facility. Stockton,to#6981.WP1 3