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As-Built CQA Report for the Construction of Area 2A at the Foothill Sanitary Landfill San Joaquin County,California tests had been performed and used for previous Module 1 liner for the Foothill Landfill and also for the North County Landfill Area 4 and 5 composite Liners. • The tests results for sandwich tests (Test Series 4) confirmed that the specified post-peak strengths were met at all 5 normal stress points and that the sliding occurred on the GCL/geomembrane interface. Side Slope Liner • The post-peak strengths for the HDPE geomembrane/geocomposite interface for the side slope liner (Test Series 3) met the minimum specified values at normal stresses of 6,000, 8,000 and 12,000 psf,but were slightly below the specified values at normal stresses of 1,000 and 4,000 psf. • Similar results were also confirmed for sandwich tests for side slope liner (Test Series 5). • Geosyntec evaluated the test results and confirmed that these slightly lower post- peak strengths at 1,000 and 4,000 psf normal stresses had no impact on the stability analysis. This confirmation is documented in their Construction Memorandum#3 included in Appendix C.2a. 6.5 GEOSYNTHETICS INSTALLATION • 6.5.1 General The geosynthetics installation for Area 2A Liner started on July 14, 2015 and was completed on September 25, 2015. The installation initially commenced with GCL on the north slope followed by 60-mil DST HDPE geomembrane. The liner system was tied in to the existing Area 1 liner. On completion of the north slope installation, GBE installed GCL and HDPE on the floor and then on the east slope. Once the liner was completed, a leak location survey was performed on the bare geomembrane. GBE installed geocomposite on side slopes and GDM on the floor following the leak location survey. The 8-oz geotextile was installed on top of GDM on the floor prior to placement of operations layer on the floor and lower 20 feet of the slopes. Another leak location survey was performed on the completed liner system with the operations layer in place. Side slope liner above the 20 feet was covered with sacrificial geomembrane. The configuration for installation on the floor and side slopes followed the configuration tested in interface strength tests. All of the installation activities were monitored full time by AES CQA monitors under the supervision of the CQA Manager. 6.5.2 GCL GBE installed the GCL on the side slope and floor areas between July 14 and August 3, 2015. The • GCL was installed on top of prepared subgrade on the side slope or the foundation layer on the PA14 ProjectW4-101(SJCDPW North County and Foothill)IFoothill CQAIReportlFinal ReportlFoothill CQA Rport-Final.docx 24