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Although Forward is not currently treating gasoline contaminated soil, these soils have been treated in the past and may be treated in the future. Gasoline- contaminated soils will be treated in WMU G-North or G-South by a vapor extraction and thermal oxidation technique in accordance with San Joaquin County Unified Air Pollution Control District regulations on uncontrolled air emissions. The vacuum extraction (VE) treatment system will consist of treatment cells approximately 20 feet wide at the base by 200 feet long and 5 feet high. The volume of soil in each treatment cell will be approximately 550 cy. The base of each treatment cell will consist of compacted native soil covered by a 20-mil polyethylene liner. The stockpiled soil will be placed in 1-foot-thick lifts over the treatment cell liner to a height of approximately 5 feet. An air delivery system consisting of perforated PVC pipe will be installed in each treatment cell to aid in removing residual volatile organic chemical concentrations present in the soil. A flinch pipe will be placed at the bottom of the treatment cell with a set of three pipes placed at the top. The top pipes will be equipped with a one-way valve. When a vacuum is applied to the bottom pipe, air will flow through the one-way valve in the top pipes and Ask through the soil to the bottom pipe. The vacuum extraction pipes from the various cells will be manifolded together such that the air will flow to an internal combustion engine. Each treatment cell is covered with 10-mil polyethylene sheeting to prevent uncontrolled air emissions of volatile organics during the remediation process. The treatment process takes approximately 12 weeks from the start of vacuum extraction. To verify that vacuum extraction.has sufficiently reduced soil contaminant levels below the designated level for disposal, soil samples will be collected from the cell at the initiation of remediation and then monthly to monitor the remediation process. The samples will be analyzed for total petroleum hydrocarbons (TPH) as gasoline and benzene toluene, ethylbenzene, xylene (BTEX). Approval for final disposition of the material will be requested from SJCPHS. Upon verification that the soil in a cell has been adequately cleaned, the soil will be removed and disposed onsite in an appropriate waste cell or used as daily or intermediate cover. The piping, liner, and cover will be removed and, if possible, used for the next batch of soil. Forward Landfill JTD 6-16 J:\Allied\Forward\JTD Amendment\Final JTD AmendmentUTD Sec 6 080105.doc:5/22/02 Rev. 1:7/2002:Rev.2:4/2003;Rev 3:6/2003 BRYAN A.sTiRRAT s ABBOCIATES Amendment No.1:8/1/2005