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of the coarse gravel will be 1.0 cm/sec. The coarse gravel will be washed, rounded, and have a maximum particle size of 1 inch with less than 20 percent of particles smaller than 1/2 inch, 5 percent finer than the No.4 sieve,and 2 percent finer than the No.200 sieve.The leachate collection pipe will be perforated at third-points,with 1/2-inch-diameter holes,spaced 6 inches on center. The granular drainage material of the base LCRS will be overlain by a sheet of nonwoven geotextile filter fabric. The geotextile functions as a filter to separate and prevent intrusion of fine materials from the overlying protective operations layer into the granular drainage material. This will allow the granular drainage material to retain its specified hydraulic conductivity by preventing clogging from piping of fines. Leachate in WMU FU-08 will drain to temporary sumps at the eastern WMU FU-08 edge.As WMUs to the east of WMU FU-08 are constructed, the LCRS pipes and trenches will be extended and will ultimately flow to permanent sumps on the eastern boundary of the site. The temporary sumps are composite lined and consist of a 4-ft deep pit with 3:1 side slopes. Within each sump will be a 5-foot diameter,perforated HDPE tank surrounded by coarse gravel. Within each tank will be a submersible pump for pumping out leachate. All leachate will be directed to WMU F-West,the Class H leachate impoundment, from where it will be evaporated. The leachate piping to WMU F-West will be installed by Forward site personnel following completion of WMU FU-08 and prior to refuse filling. Specifications for the granular drainage material, coarse gravel, HDPE pipe, filter and cushion geotextile, and geocomposite drainage layers are included in Appendix C. 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. 5.2.3 Base LCRS in Northern Portion of WMU FU-08 The base LCRS in the northern portion of the cell will be constructed of a 6-inch-thick layer of clean granular material with a minimum hydraulic conductivity of 0.1 cm/sec draining towards leachate collection pipe trenches. The particle size of the granular drainage material has been limited to a maximum of 3/8-inch to protect against puncture of the adjacent geotextile filter fabric, and to a maximum of 3 percent of particles finer than the No.200 sieve to maintain its permeable nature. The leachate collection trenches will contain 3-inch diameter SDR 11 perforated HDPE leachate collection pipes (see pipe sizing and loading calculations in Appendix B). The pipes will be placed within each leachate collection trench to increase the drainage capacity of the LCRS. Each pipe will be surrounded by coarse gravel wrapped with a nonwoven geotextile to prevent migration of fine particles from the overlying LCRS granular drainage material. The minimum hydraulic conductivity of the coarse gravel will be 1.0 cm/sec. The coarse-gravel will be washed and have a maximum particle size of 1 inch with less than 20 percent of particles smaller than 1/2 inch, 5 percent finer than the No.4 sieve, and 2 percent finer than the No.200 sieve. The leachate collection pipe will be perforated at third-points,with 1/4-inch-diameter holes,spaced 6 inches on center. Termination berms will be constructed around the perimeter of the unit. The interior slopes of the termination berms will be lined with a 60-mil HDPE geomembrane to contain leachate within the unit. WMU FU-08 REPORT 5-6