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• 60-mil,double-sided textured HDPE geomembrane liner; • Cushion geotextile; • One half-foot thick gravel blanket drainage layer with a minimum hydraulic conductivity of 0.1 cm/sec; • Nonwoven geotextile filter fabric; • One half-foot thick general earthfill; • Needlepunched reinforced geosynthetic clay liner(GCL); • 60-mil, single-sided textured HDPE geomembrane(textured side placed against GCL); • Geocomposite drainage net(GDN); • One-foot thick protective operations layer Connection, transition, termination, and anchorage details have been designed (see Construction Drawings,Appendix A)to maintain continuity among all components and to provide connection access for future systems. 5.1 Lining System As shown on the Construction Drawings (Appendix A), the WMU FU-06 base lining system in the southern portion of the cell will consist of a 2-foot-thick compacted,clay liner overlain by a 60-mil thick, double-sided textured HDPE geomembrane. The side slope liner will consist of a GCL overlain by a 60-mil thick, single-sided textured HDPE geomembrane. The base lining system meets the current prescriptive Title 27 regulations and complies with Forward's WDRs. The side slope liner is an engineered alternative that complies with Forward's WDRs and has been previously approved at the Forward Landfill for WMUs D-99,D-00, D-01, D-02, FU-03,FU-04, and FU-05. The interface liner is also an engineered alternative that complies with Forward's WDRs and has been previously approved at the Forward Landfill for WMUs D-94,D-97,D-98,D-99,FU-03,FU-04,and FU-05. 5.1.1 Clay Liner The clay liner will be constructed to meet the Specifications included in Appendix C. It will consist of fine-grained soils with significant clay content and without organic matter. The material will have at least 30 percent of particles passing a No. 200 U.S. Standard sieve and be classified as SC (clayey sand), CL(lean clay, sandy or silty lean clay), or CH(fat clay, sandy or silty fat clay) by the Unified Soil Classification System(USCS). The clay liner will have a maximum field hydraulic conductivity of 1 x 10-7 cm/sec when compacted to a minimum relative compaction of 90 percent at a water content at least 2 percent greater than the optimum water content as determined by the modified Proctor compaction test(ASTM D1557). A field permeability test (sealed double ring infiltrometer [SDRI]) was conducted on onsite soils in 2001 to assess their suitability as clay liner material. The field permeability test indicated that the onsite soils could achieve a field hydraulic conductivity of 1 x 10-7 cm/sec. The clay liner will be constructed using techniques and materials similar to those used in constructing the test pad for the field permeability test. WMU FU-06 REPORT 5-3