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t � Mr. Robert McClellan October 1 , 2010 Page 2 Plan that proposes the installation of an additional 15 LFG vertical extraction wells and 10 soil vapor extraction(SVE)wells. Once the LFG extraction wells and SVE wells have been installed and are operational, Forward proposes to proceed with the installation of the perimeter LFG compliance probes as described in the conditionally approved Addendum and response letter, dated March 22, 2010 and May 17, 2010, respectively. However,the perimeter probe abandonment will not occur until the permitted boundary expansion has been approved. A summary of that work plan has been included for reference. BACKGROUND The Forward Landfill is located at 9999 South Austin Road, Manteca, San Joaquin County, California. Landfill operations began in 1954, and the landfill was formerly known as the Austin Road Landfill. The Austin Road Landfill was purchased by Forward, expanded, and renamed the Forward Landfill. The Austin Road Landfill, now referred to as the Austin Road Unit, is the north unit of the landfill. Forward has documented regulatory exceedances of methane in perimeter gas probes GP-11 and GP-12, which are located along the current southwestern compliance border of the site (27 CCR §20921-20937). In accordance with the 27CCR §20937 (a)(4), "when the results of landfill gas monitoring indicate concentrations of methane or trace gases in excess of the compliance requirements in §20921(a), the operator must construct a gas control system that meets the criteria of§20939..." The landfill currently has a gas control and collection system(GCCS)that consists of LFG extraction wells throughout the Forward and Austin Road Units, but, as demonstrated by the exceedances observed in perimeter probes GP-11 and GP-12, elevated methane levels are migrating outside of the compliance boundary. Forward suspects that the source of the LFG detected in probes GP-11 and GP-12 is the unlined Austin Road Unit. The mitigation pathway of the LFG is likely from the Austin Road Unit, through the permeable soils that underlie the Forward Unit base liner, to the Forward Unit waste perimeter. As evidenced by methane readings in compliance for the remaining perimeter probe network, gas migration from the Austin Road Unit appears to be limited to a southwestern migration direction, likely due to preferential flow pathways in the subsurface permeable media. To comply with 27CCR §20921-20937, Forward is proposing to expand its current GCCS through the installation of vertical LFG extraction wells within the waste units, and SVE extraction wells in native soil along the southwestern compliance boundary. The expansion of the GCCS will accomplish two goals: (1) enhance recovery and destruction of LFG within the waste units through the installation of 15 vertical extraction wells; and(2)the construction of a LFG barrier via 10 SVE wells to collect and destroy any LFG that may escape the Austin Road Unit,travel beneath the Forward base liner, and towards the southwestern compliance boundary. Once the gas collection system has been expanded and the site has demonstrated that the GCCS upgrades are effective in reducing the LFG concentrations, Forward plans to proceed with the installation of the perimeter probes along the proposed compliance boundary. In addition, abandonment of the perimeter probes along the current southwest border will not occur until the permitted boundary expansion has been approved.