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rock will be allowed) to protect the underlying geomembrane from puncture or tears. In addition, a protective geotextile cushion will be placed between the geomembrane and granular drainage material for added geoemembrane puncture resistance. If the granular drainage material appears more angular than desired by the Engineer and QA/QC Consultant, the Contractor will be required to demonstrate the suitability of the material by utilizing an on-site test area. The test will consist of placing a 1-foot thickness of granular drainage material on a 15-foot by 30-foot piece of 60-mil HDPE geomembrane and cushion geotextile using the same equipment and procedures as the Contractor is planning to use to place the granular drainage material in WMU FU-14. The QA/QC Consultant will then inspect and, if necessary, test the 60-mil HDPE geomembrane for damage and either accept or reject the angularity of the proposed granular drainage material. The leachate collection trenches will contain 6-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 and to protect the underlying geomembrane. The minimum hydraulic conductivity 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 15 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-14 will drain to temporary sumps at the eastern WMU FU-14 edge. As WMUs to the east of WMU FU-14 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 II 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-14 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. 5.3 Protective Operations Layer A protective operations layer will be placed above the 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 WMU FU-14 REPORT.DOC 5-3