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SECTION 5 <br /> Containment System <br /> The WMU FU-13 containment system consists of a composite liner and LCRS on the base of the unit. <br /> The northern and western slopes also incorporate an interface liner to separate Class III wastes in the <br /> former Austin Road Landfill from the overlying Class II wastes to be placed in WMU FU-13. <br /> The northern boundary of WMU FU-13 will connect to the southern limit of WMU FU-08 North <br /> where the two modules intersect. The liners and LCRS in the top deck area directly north of WMU <br /> FU-13 will be connected and the leachate from this top deck area will drain to the sumps on the <br /> WMU FU-13 base. <br /> The area where WMU FU-13 and WMU FU-08 North will be connected is a relatively flat area. The <br /> portion of the existing WMU FU-08 North southern termination berm located at the intersection with <br /> WMU FU-13 will be removed. The clay liner in WMU FU-08 North will be transitioned to a 60-mil <br /> HDPE geomembrane and extended to meet the geomembrane liner in WMU FU-13. The gravel layer <br /> in WMU FU-08 North will be extended to connect to the geocomposite drainage net at the top of the <br /> WMU FU-13 northern and western slopes. Leachate from the portion of WMU FU-08 North that <br /> intersects WMU FU-13 can then flow directly into the WMU FU-13 sumps. Because the connection <br /> area is relatively flat and is underlain by refuse in the former Austin Road Landfill, a geogrid is <br /> incorporated in the connection area to support the overlying liners and LCRS systems. <br /> The base liner system for WMU FU-13 consists of the following,from bottom to top: <br /> • Prepared subgrade; <br /> • Minimum 2-foot thick compacted clay liner with a maximum field hydraulic conductivity of 1 x <br /> 10-7 cm/sec; <br /> • 60-mil,double-sided textured HDPE geomembrane liner; <br /> • Cushion geotextile; <br /> • One-foot thick blanket gravel and pipe network drainage layer with a minimum hydraulic <br /> conductivity of 0.1 cm/sec; <br /> • Nonwoven geotextile filter fabric; <br /> • One-foot thick protective operations layer <br /> The northern and western side slope and the interface liner system consists of, from bottom to top: <br /> • Prepared subgrade (for 2:1 slopes) or approximately 3-ft thick- foundation layer over former <br /> Austin Road Landfill areas; <br /> • Needlepunched reinforced geosynthetic clay liner(GCL); <br /> • 60-mil, single-sided textured HDPE geomembrane(textured side placed against GCL); <br /> WMU FU-13 REPORT.DOC 5-1 <br />