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1.2 Closure Sequencing The staged closure of the FL will be performed in accordance with the applicable regulatory standards included in 27 CCR, Chapters 3 and 4 and 40 CFR, Subpart F. The closure sequencing for the FL will be implemented in eight stages (Stages I through VIII) as shown on Figures 1 through 8. The closure cost estimate is described in Section 1.8 of this document. The components and systems required for the staged closure of the FL include the final grading plan, final cover design, drainage, erosion and landfill gas system modifications as well as site security. A description of these closure components, as well as a schedule for construction of the final closure stage, is presented in the following subsections. Partial final closure projects are allowed under 27 CCR, Section 21120. As described herein, eight -staged closure projects will be implemented over the life of the FL with each one having a separate partial final closure plan prepared two years in advance of the anticipated closure stage. These improvements will clearly enhance landfill containment and environmental protection. A primary benefit of the partial or early closure is the reduction of potential surface water infiltration, which in turn will reduce leachate generation, as well as the related surface seeps that are sometimes observed in unclosed areas following storm events. Termination points between a given closure stage and the active fill areas will be separated by the exterior benches. The linear low-density polyethylene (LLDPE) component of the final cover system will be placed at transition points between stages and placed in an anchor trench. When the next adjacent closure stage is constructed, the upper end of the vegetative soil covering the in-place LLDPE for the previous stage will be excavated back and a new layer of LLDPE which represents the start of the next stage will be placed (or shingled) over the top of the previous stage LLDPE and welded together. A final cover detail at the bench which will be typical of the termination/transition at the benches is shown on Figure 9. Those interface connections between the closure and active fill areas which are not separated by an exterior bench, that is the connection which is made laterally, will be marked. Additional vegetative soil will also be placed to overlap the edge of the final cover by 10 feet. The protective soil and markers will provide adequate protection of the final cover and form a clear separation for continuing active fill operations outside the closure areas. In areas of vehicle activity, the vegetative soil overlap will be 20 feet. In addition, those interim and final drainage control structures controlling surface water run-on and/or run-off for the designated closure stages will be inspected and maintained to appropriately divert run-on and control run-off. The landfill gas control system will be installed as the site is developed. Permanent gas migration monitoring probes have been or will be installed prior to the closure of each staged construction period. The landfill gas system will be taken off-line and those drainage control system features over refuse will be removed while the 2 SWT Engineering Forward Landfill - PCPCMP Amendment (Z:\PROJECTSwllied Waste\Forward\JN81013 5 yr Review Plan\JTD Amd 3 PCPCMP Amd 3 Dec 08\PCPCMP Amend 3 121808.doc; Amendment No. 3:12/18/08)