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Specifications for the granular drainage material, coarse gravel, HDPE pipe, filter and cushion geotextile, and geocomposite drainage layers are included in Appendix C Specifications. Quality assurance testing of the LCRS materials is outlined in the CQA Manual (Appendix D). The testing includes particle size and hydraulic conductivity for the granular drainage material and coarse gravel and manufacturer's certification of material properties for the geotextile and GDN. Details of the composite liner and LCRS components are shown on the Construction Drawings in Appendix A. 5.3 Protective Operations Layer A protective operations layer will be placed above the base LCRS to protect the LCRS, pipes, and composite liner from construction and operations traffic. The protective operations layer will consist of a minimum 12-inch-thick layer of generally sandy material excavated from onsite stockpiles. The maximum particle size of the sandy material will be limited to 1 inch to protect the underlying geotextile or GDN from puncture. A 12-inch-thick protective operations layer will also be placed above the lining and LCRS system on the slopes, concurrently with waste placement. The side slope operations layer will be placed a maximum of 10 feet ahead (vertically)of the waste to minimize the tensile load developed within the GDN. The operations layer will be placed using a wheel loader, so that no equipment loads are exerted on the liner. Forward has previously used a Caterpillar 966F wheel loader with a 4.5 cy bucket to place operations layer on the WMU slopes. Specifications for the protective operations layer are included under general earthwork(Appendix C). 5.4 WMU F-West Leachate Impoundment The WMU F-West Leachate Impoundment has been designed to store approximately 2,700,000 gallons of leachate with 2 feet of freeboard (an additional 531,000 gallons) that will be generated from the former Austin Road Landfill area, and the proposed lined area of the former Austin Road Landfill area that was south of Little John's Creek. Leachate will be pumped from the permanent double-lined sump within WMU FU-03 along the southern edge of the landfill development to the WMU F-West leachate impoundment. The Leachate Impoundment is double lined with a primary 60-mil HDPE and a secondary 60-mil HDPE which is underlain by a GCL. Between the primary and secondary liner,there is a drainage composite net which drains to a sump with a riser. The riser pipe is a 12-inch perforated HDPE in the sump area which transistions to solid 12-inch HDPE up the side slope, which is approximately 4:1 gradient. The sump riser pipe has a blind flange on the end which can be removed to check and remove liquids from the sump. A continuous gravel log anchor will be placed at the tope of the bottom of the Leachate Impoundment to hold down the liner in case of head build up beneath the primary liner system. It is anticipated that as additional cells are developed within the former Austin Road borrow area and on the top deck areas of the former Austin Road Landfill, leachate generation will increase. The 2,700,000 gallon capacity of WMU F-West is more than adequate to handle leachate generated from the initial development from these areas. As landfill cell development continues, a Leachate Management Plan to include the construction of a leachate transfer main to transfer leachate to the WMU F-North leachate basin will be necessary to effectively utilize existing permitted environmental leachate management controls. Since the WMU F-North basin leachate levels have been declining (see Appendix B for 2000 and 2001 leachate volume records), and will continue to decline as landfill operations within Forward Landfill area diminish and partial closure occurs, the additional resulting available storage capacity and evaporation potential within WMU F-North can be utilized to effectively manage overall site leachate generation and disposal. FORWARD LANDFILL WMU F-03 AND F-WEST DESIGN REPORT 5-5