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constructed since 1993, a blanket LCRS has been installed over the lined base and slopes. The same LCRS system will be used in the expansion area. The general LCRS design will consist of a one-foot thick gravel layer immediately above the base liner. A network of leachate collection pipes placed within the gravel layer will convey accumulated liquid to the designated sump areas. Dedicated pumps will be installed in each sump to lift the leachate through a riser pipe for discharge to onsite leachate evaporation ponds. As discussed earlier, one of the leachate ponds will be removed and relocated (see Figures 7 and Q. Additional leachate ponds will be added in the southwest corner of the expansion area and in the area of the current administrative offices. LANDFILL GAS CONTROL SYSTEM The current collection system consists of 216 vertical landfill gas wells, 46 soil vapor extraction wells, eight (8) horizontal gas collectors, and seven (7) LCRS riser connections; however, changes to the system are ongoing, as additional collectors are added in response to changing landfill conditions. The control system currently consists of two enclosed ground flares and a landfill gas to energy plant. One flare is a 2,000 scfm LFG & E International unit installed in 2002, and the second is a 3,400 scfm John Zink unit installed in 2007. Eighteen additional wells are connected to a landfill gas to energy plant operated by Covanta. The landfill gas system is more fully described in Sections 3.3.4 and 4.4.1. This system will be extended into the expansion area with of main and lateral collection lines connected to a well field consisting of vertical collection wells and horizontal collection trenches. 5.3 CLOSURE/POST-CLOSURE MAINTAINANCE PLAN An updated PCPCMP will be prepared, as part of the JTD, to reflect the proposed expansion areas and will be submitted as part of the SWFP application package. The PCPMP will be similar to the current PCPMP but will incorporate the expansion area. The preliminary closure and post-closure cost estimate will be revised to reflect the updated PCPCMP for the proposed expansion. A Final Closure and Post-Closure Maintenance Plan (FCPCMP) will be prepared and submitted to the appropriate regulatory agencies (e.g., CIWMB, LEA, and RWQCB) two years prior to the anticipated closure date. Forward Landfill Project Description 5-9 BRYAN A.STIRRAT&ASSOCIATES (J:\Allied\Forward\2007.0018 Lateral Expansion\Reports\Prof Descrip\021308 Final Proj Des\Sec 5.doc:2/13/2008)