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SECTION 5 Containment ye The southern portion of the WMU FU-08 containment system consists of a liner and LCRS on the base of the unit and a composite side slope liner on the northern excavation slope. The northern slope in the southern portion of the cell also incorporates an interface liner to separate Class III wastes in the former Austin Road Landfill from the overlying Class II wastes to be placed in WMU FU-08. The northern portion of WMU FU-08 is located on the top deck of the former Austin Road Landfill. The interim final cover serves as the base liner for this portion of the cell. A LCRS will be placed over the interim final cover. Leachate will drain to header pipes located along the southern termination berm and then routed via a solid 3-inch HDPE pipe to temporary leachate storage tanks. Once the northern and southern portions of WMU FU-08 are constructed and approved for disposal, the liners and LCRS in the top deck area directly north of the southern portion of WMU FU-08 will be connected and the leachate will drain to the sump in the southern portion of WMU FU-08. In the northern portion areas that are not directly north of the southern portion of WMU FU-08,the leachate will continue to be collected and routed to temporary leachate tanks. Once the WMUs to the east of WMU FU-08 are constructed, the liners and LCRSs in the northern and southern portions will be connected and leachate will flow to the LCRSs in the southern portion. The area where the northem and southem portions of VVMU FU-08 will be connected is a relatively flat area. The existing southern termination berm in the northern portion of WMU FU-08 will be removed in the connection zone. The clay liner in the northern portion of VVMU FU-08 will be transitioned to a 60-mil HDPE geomembrane and extended to meet the geomembrane liner in the southern portion of WMU FU-08. The gravel layer in the northern portion of WMU FU-08 will be extended to connect to the geocomposite drainage net at the top of the northern slope in the southern portion of WMU FU-08. Leachate from northern portion of WMU FU-08 can then flow directly into the southern portion of WMU FU-08 and to the sump. Because the connection area is relatively flat and is underlain by refuse in the former Austin Road Landfill, a geogrid is incorporated in the connection area to support the overlying liners and LCRS systems. Once the northern portion of WMU FU-08 is approved for disposal, Class III refuse will be placed above the northern portion. The Class III refuse will extend a minimum of 50-ft to the south of the boundary between the northern and southern portions and the southernmost Class III refuse face will be sloped to the south. The base liner system for the southern portion of WMU FU-08 consists of the following, from bottom to top: • Prepared subgrade; • Minimum 2-foot thick compacted clay liner with a maximum field hydraulic conductivity of I x 10-7 cm/sec; • 60-mil,double-sided textured HDPE geomembrane liner; • Cushion geotextile; WMU FU-08 REPORT6 5-1