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Manufacturer-recommended procedures for proper installation of the GCL are included in the Specifications. Inspection and testing of the GCL material and installation are described in the CQA Manual included in Appendix D. The GCL will be covered with a 60-mil thick, single-sided, textured HDPE geomembrane (textured side against GCL) placed concurrently with GCL deployment. By covering all deployed GCL with HDPE geomembrane, the GCL will be effectively protected from possible moisture damage. However, if the GCL becomes saturated during construction, it will be removed and replaced in accordance with the Specifications (Appendix Q. The termination edge of the GCL and geomembrane will be placed in perimeter anchor trenches. 5.1.3 HDPE Geomembrane The 60-mil HDPE geomembrane will be installed in accordance with the Specifications (Appendix Q. Extensive CQA will be performed on the geomembrane to identify and repair defects. Tests will be performed on both the geomembrane and on the field-constructed seams. A leak location test will be performed on the geomembrane following installation of the geomembrane alone and following placement of the protective operations layer. CQA inspection and testing procedures are defined in the Specifications(Appendix C)and in the CQA Manual (Appendix D). 5.2 Leachate Collection and Removal System (LCRS) Design calculations were performed to establish that the WMU FU-04 LCRS would meet the Title 27 requirements that the LCRS be designed, constructed,maintained, and operated to collect and remove twice the maximum anticipated daily volume of leachate from the disposal unit. To comply with site WDRs and Title 27 requirements, the 1,000-year, 24-hour storm was used in estimating leachate volumes for the Class II portion of the cell and the 100-year, 24-hour storm for the Class III portion of the cell. Calculations were based on a granular drainage layer hydraulic conductivity of 0.1 cm/sec. The leachate generation analysis was performed using the Hydrologic Evaluation of Landfill Performance(HELP)computer model (Schroeder et al, 1988)(see Design Calculations,Appendix B). The cross section analyzed by the HELP model corresponds to a condition of maximum anticipated leachate generation. The maximum leachate generation condition was assumed to occur during placement of the first 10-foot thick lift of refuse in WMU FU-04. The maximum leachate impingement rate estimated by the HELP model for the Class II portion of the cell is 0.13 inches per day. The rainfall rate for the 1,000-year, 24-hour storm is 4.79 inches/day. The HELP analysis shows that an LCRS with a permeability of 0.1 cm/sec will maintain less than one foot of head over the liner. For the Class III portion of the cell, the peak daily rainfall generated by the HELP model was 3.37- inches, which is greater than the 100-year,24-hour storm precipitation of 3.25 inches. Based on these assumptions,and the designed LCRS components, the maximum leachate impingement rate estimated by the HELP model is 0.12 inches per day. 5.2.1 Slope LCRS The LCRS on both excavated and interface lined slopes will consist of a GDN placed directly upon the HDPE geomembrane. The GDN is comprised of a sheet of geonet drainage material with a nonwoven geotextile filter fabric bonded to one side. To maintain its position on the slope, the GDN EU-04 REPORT.DOC 5-4