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As-Built CQA Report for the Construction of Area 2A at the Foothill Sanitary Landfill San Joaquin County,California • floor. The GCL rolls were transported to the top of side slopes on a spreader bar attached to a forklift. On the side slope, crew of installers manually pulled the GCL from the roll attached to the spreader bar, and walked down the slope for the length of the area to be covered. Care was taken that no equipment traveled on the GCL surface. On the floor, the GCL was deployed directly on the foundation layer by unrolling material off the spreader bar while the forklift travelled backwards. GCL was installed with the heat burnished geotextile side down (as tested in the interface strength tests). AES CQA Monitors observed the deployment of GCL to verify compliance with the specification requirements. In addition, AES verified that a minimum overlap (between adjacent panels) of 18 inches on the slope and 12 inches on the floor was achieved. Granular bentonite was placed along seams at a rate of 1/a. lb/ft. GBE heat bonded GCL panels on the floor with a leister gun. No horizontal seams were allowed on the side slopes. The GCL installed on any day was always covered by overlying HDPE geomembrane on the same day to minimize exposure to weather. A summary of GCL deployment is presented in Appendix H.1. The as-built panel layout drawing prepared by GBE is included in Appendix D.3. 6.5.3 HDPE Geomembrane GBE installed the 60-mil DST HDPE geomembrane on the side slope and floor areas between July 14 and August 4, 2015. The HDPE geomembrane rolls were transported to the cell side slopes on a • spreader bar attached to the forklift. After positioning the forklift, a crew of installers manually pulled the 60-mil HDPE geomembrane from the roll attached to the spreader bar and walked down the slope for the length of the area to be covered. A slip sheet was used during the installation of geomembrane against GCL to minimize displacement of GCL during geomembrane deployment. For the floor liner, one forklift was stationed with the geomembrane roll on the bare ground at the end of GCL panel that was already installed and the geomembrane was pulled using a pulley system supported by another forklift stationed at the other end. No vehicular traffic was allowed on installed GCL panels or any other geosynthetic materials. The summary of DST HDPE geomembrane deployment is provided in Appendix H.2. The as-built panel layout drawing prepared by GBE is included in Appendix D.3. GBE used two methods of seaming the HDPE geomembrane panels: the dual-track hot-wedge fusion seaming method,used for most of the panel seaming,and the extrusion fillet method, used for small seam segments, tie-ins, repairs and at penetrations. Non-destructive testing was performed on all of the 60-mil HDPE geomembrane seams. The air channel formed in the 60-mil HDPE geomembrane seam during dual-track hot-wedge fusion seaming permitted air-pressure testing of the seams. Non-destructive testing for the extrusion-fillet welding method was performed by vacuum testing as discussed in detail at the end of this section. A minimum overlap of 4 inches was provided during hot-wedge fusion seaming of 60-mil HDPE geomembrane and a minimum 3 inches • was provided during extrusion welding. P:114 Projects114-101(SJCDPW North County and Foothillff oothill CQAIReport\Final ReportToothill CQA Rport-Final.docx 25