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• Construction of the Interim Final Cover for the Existing Austin Road Landfill is documented in the Final Construction Quality Assurance Report for Closure Construction of the Austin Road Portion of the Forward Landfill(Vector Engineering,2002). • The northern portion of WMU FU-06 will accept only Class III wastes until it is overlain by the interface liner system. The base liner in the southern portion of WMU FU-06 will encompass approximately 8 acres and will extend approximately 600 feet in the north-south dimension and 600 feet in the east-west dimension. The base of WMU FU-06 will be at approximately elevation 15-feet,which is about 25 feet below the surrounding ground surface.A composite lining system consisting of a 2-foot-thick clay liner overlain by a 60-mil, high-density polyethylene (HDPE) geomembrane, and LCRS consisting of 1 foot of granular drainage material will be constructed on the WMU FU-06 base. A permanent double composite lined sump will be constructed at the southern edge of the WMU FU-06 base. Side slope liners will be constructed on the northern and southern 2:1 (horizontal:vertical)slopes.The side slope liner on the north slope consists of a geosynthetic clay liner(GCL) overlain by a 60-mil, single-sided textured, HDPE geomembrane, and a single-sided geocomposite drainage net (GDN). The side slope liner on the south slope consists of a geosynthetic clay liner (GCL) overlain by a 60-mil, single-sided textured, HDPE geomembrane. While the geocomposite drainage net on the south slope has been incorporated into the south slope liner system in the past, testing of landfill gas in the southern anchor trenches of WMU FU-03, FU-04, and FU-05 have shown high levels of methane. The geocomposite drainage net was eliminated on the south slope because it was a likely conduit for LFG into the south anchor trench. Assuming that the elimination of the geocomposite drainage net reduces or eliminates the migration of landfill gas into the anchor trench, future WMUs will also eliminate the geocomposite drainage net on the south slope.' A portion of the northern WMU FU-06 slope is at an approximately 5:1 (horizontal to vertical)grade and is underlain by the former Austin Road Landfill. To provide support for the side slope liner, an approximately 4 to 5-ft thickness of subgrade fill (1-ft of subgrade fill was previously placed as intermediate cover over the former Austin Road Landfill) will be placed and compacted over the portion of the former Austin Road Landfill that underlies WMU FU-06. The northern portion of WMU FU-06 encompasses a portion of the interim final cover that was constructed over the former Austin Road Landfill in the fall of 2002. The 2-ft foundation, 1-ft thick clay liner, and 1-ft vegetative layer of the interim final cover serve as the base components of the WMU FU-06 cell in this area. The interim final cover generally grades at a 3 percent slope from north to south. 1 In some of the future WMUs,the orientation of the cell will change and the geocomposite drainage net would be eliminated from the east slope. WMU FU-06 1-2