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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-04 base lining system in the central 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, and FU-03. 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,and FU-03. 5.1.1 Clay Liner The clay liner will be constructed to meet the Spe5-4cifications 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. Laboratory hydraulic conductivity, particle size analyses, compaction, Atterberg limits, and field density and water content testing will be performed on the clay liner during construction as part of the construction quality assurance(CQA)program.The CQA Manual is included in Appendix D. After constructing the clay liner, the surface of the clay will be protected from desiccation cracks by keeping the surface moist. Immediately prior to geomembrane deployment, the surface of the clay will be prepared by rolling with a smooth drum roller. The entire base of the central portion of WMU FU-04 will be covered by a 60-mil, single-sided, textured HDPE geomembrane liner (textured side against clay). Terminations and future connection edges of the geomembrane will be placed under temporary berms to hold the liner secure during construction and filling. Along future connection edges, the geomembrane edges will be protected by geotextile, plywood sheets, and buried under earth berms. 5.1.2 Geosynthetic Clay Liner The GCL will be placed by deploying GCL panels and overlapping panel seams. The GCL panels will be anchored in the same trench as the HDPE geomembrane and GDN around the WMU limits. FU-04 REPORT.DOC 5-3