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As-Built CQA Report for the Construction of Area 2A at the Foothill Sanitary Landfill San Joaquin County,California • Trial Seam Testing Prior to the start of seaming operations and after the mid-day break, GBE performed trial seam welds on all seaming equipment to verify the performance of welding equipment, seaming methods, and conditions. The trial seams were made from a piece of the HDPE geomembrane and were seamed together under the same conditions as the actual field seaming. The HDPE geomembrane trial seams were tested for peel adhesion (peel) and bonded seam strength (shear), and were required to fail in the geomembrane sheet, as characterized by the film tear bond (FTB) and not in the welded seam segment (non-FTB). For all seaming equipment, a minimum of four, one-inch-wide test specimens were obtained from each trial seam. Two of the specimens were tested for peel and two specimens were tested for shear. For the dual-track hot-wedge fusion seaming method, both sides of the seam specimens were tested for peel adhesion. The results of fusion and extrusion trial seams are presented in Appendix I. AES CQA Monitors monitored the seaming conditions including ambient temperature, sheet overlap, and seam preparation. In addition, the CQA Monitors marked samples for destructive seam tests and located defects on the HDPE geomembrane seams and liner. Summary of fusion and extrusion seam construction and non-destructive testing for the geomembrane is presented in Appendix J. The specified minimum values for shear and peel for 60-mil fusion and extrusion welded seams were as follows: • Pro perty Unit Test Method Specification Shear Strength Fusion Extrusion i ASTM D6392 120 Peel Strength-Fusion ppi ASTM D6392 91 Peel Strength-Extrusion ppi ASTM D6392 78 Repairs During installation of the HDPE geomembrane, a number of locations required repairs to the liner. These included seam T-intersections, penetration in the liner system resulting from leachate extraction riser pipes, cuts for destructive test sampling, cuts placed in the liner to perform pressure testing, construction damage, leaks found during vacuum testing or air-pressure testing, or areas left unseamed. The majority of these defects resulted from the normal course of geomembrane installation. Each defect was identified, and GBE repaired all defects to the HDPE geomembrane and welded the seams by extrusion or fusion welding methods as described above. Appendix K presents a summary of the defects including locations, repair dates and non-destructive testing dates. Non Destructive Seam Testine GBE performed non-destructive seam continuity testing as seaming of 60-mil HDPE geomembrane progressed, by using air-pressure testing on dual-track hot-wedge fusion seams, vacuum box PA14 Projects114-101(SJCDPW North County and Foothillff oothill CQAIRepoffinal ReportToothill CQA Rport-Final.docx 26