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Final Construction Quality Assurance Report —WMU FU -13 Forward Landfill prepared the compacted soil for geosynthetics deployment by working the surface with a smooth drum roller. GLA's CClA Monitor observed the smooth drum rolling procedure to verify that the Contractor left a smooth surface, free of ridges, indentations, or oversize soil components, that could damage the overlaying geosynthetics. Once this surface preparation was complete, the area was considered ready for geosynthetics deployment. These areas were then inspected by GLA's CQA Monitor and the liner installer, Comanco, to verify that surface was acceptable for the overlying geosynthetics. When both parties agreed that the soil surface was acceptable for geosynthetics deployment, Subgrade Acceptance forms were prepared and copies exchanged by GLA's CQA Monitor and the installer's superintendent. When the installer accepts a particular area and deploys geosynthetics over the subgrade, the installer becomes responsible for the integrity of the subgrade soil surface until the project is completed. The signed Subgrade Acceptance forms are presented in Appendix E. 4.3 LOW PERMEABLE CLAY LINER Approximately 13,400 cy of material was utilized to construct a 2 -foot thick layer of low permeable clay liner on the floor of WMU FU -13. The soil borrow for this material was adjacent the east corner on the module. Before placement, the Contractor extensively ripped and moisture conditioned the soil borrow area. Scrapers collected the material and placed it on the prepared • subgrade surface in "thin" 6 -inch to 8 -inch loose lifts; additional water was added as needed and compaction achieved by the CAT 825 sheepsfoot and loaded scraper traffic. The surface of each lift of the low permeable clay liner was moisture conditioned and scarified by the CAT 825 compactor before the next lift was placed to eventually produce a 2 -foot thick layer of homogeneous material. GLA's CQA Monitor performed 81 passing in-place nuclear method moisture -density tests during placement of the low permeable clay liner soils. The Specifications required this material to be compacted to a minimum 90 percent of the maximum dry density of an ASTM D1557 Proctor, at a moisture content 3 % to 6 % above the optimum moisture content (OMC). Summaries of the field nuclear method moisture -density tests performed in the compacted low permeable clay liner I are included in Appendix D. The required testing frequencies and number of tests taken are presented in Table 1. GLA's CQA Monitor performed Proctor compaction moisture -density relationships (ASTM D - 1557A) tests, Atterberg limits determination (ASTM D-4318), and grain size distribution (ASTM D-422) tests on the low permeable clay liner material during placement. • 12 Geo—Logic ASS OG IATE S