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buried horizontal gas collector, and below grade laterals connected to a series of vertical gas extraction wells. All LFG collected from this system is routed to LFG-to-energy power plant owned and operated by Covanta Energy. Landfill gas not utilized by the power generation facility will be collected, conveyed and incinerated at the flare station. The flare station location is identified on Figure 3. A portion of the Covanta Energy LFG extraction system will be taken off-line to allow for grading activities. To keep the power plant operational, temporary laterals from the primary LFGES system will be routed to the Covanta Energy header to supplement their fuel requirements. Once the Covanta LFG extraction system is re -installed, the temporary laterals will be removed or abandoned in-place. In order to integrate the gas control system in the Stage IA partial closure area with the final cover, the following procedures are proposed for closure construction. Prior to placement of the final cover, the header system will be removed in phases, as shown in the gas system Drawing Sheets G-1 through G-14, to minimize interruption of the gas system operation. The gas header, compressed air, and condensate conveyance lines will be re -installed and made operational prior to removal of the next phase. Any affected wells will be disconnected prior to removal of the header. Headers will be re -installed if the integrity of the pipe remains intact and if it can be adjusted to a positive grade. Otherwise, the pipelines will be replaced. The main header system will remain on-line during the entire construction period. All vertical gas collection wells in place in the Stage IA partial closure area will be protected during the placement of the final cover since control of landfill gas will continue during cover construction. The top of the vertical wells or well laterals will be extended through the final cover and then reconnected to the perimeter header system line as before. Any damaged or non-functional vertical wells or laterals will be abandoned and new replacements installed to provide gas extraction coverage. Final cover material will be placed and compacted by hand around the wells or vaults to protect against damage by earthmoving equipment. In order to keep the gas system operational during Forward Landfill PFCPCMP 3-15 ZAP ROJ ECTS\Al lied Waste\Forward\Reference Files Prior JTD\June 05 Stage IA Partial FCPCMP\FL-sec3.doc: 6/16/2008