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Cripple Creek&Victor Gold Mining Company ■ <br /> Squaw Gulch VLF Phase 2A Part 1 ■ <br /> Record of Construction Report <br /> 475.0106.032 <br /> July 22,2019 <br /> 3.5.4. Geomembrane Fusion Seaming <br /> Double-wedge fusion welding was the primary method of geomembrane seaming for <br /> the Squaw Gulch VLF Phase 2A Part 1 project. Prior to fusion welding activities, trial <br /> welds were performed for each welding machine and welding technician combination <br /> for each type of geomembrane. The fusion welding trial seam logs are presented in <br /> Appendix K.2.1. The weld was inspected constantly for insufficient overlap, burnouts, or <br /> any other damage caused during the welding process. The CQA Monitor logged the <br /> welding machine and welding technician combination, the length of the seam, the <br /> direction the seam was welded, time of seaming, the welding machine temperature, <br /> and the welding machine speed. Destructive test samples were marked during fusion <br /> seaming and are discussed further in Section 3.5.6. Continuity conformance of the seam <br /> was also performed using pressure testing methods and is discussed further in Section <br /> 3.5.7. The Geomembrane Fusion Welding Summary is presented in Appendix K.3. <br /> 3.5.5. Geomembrane Extrusion Seaming <br /> At each construction bench, the deployed geomembrane was tied-into the previously <br /> placed geomembrane, overlapping a minimum of two feet. The tie-in was welded using <br /> extrusion welding methods. Any damage caused to the existing geomembrane, at the <br /> Phase 1 tie-in as it was exposed, was repaired by extending the overlap of new liner or <br /> by completely covering the damaged area with a patch. Prior to extrusion seaming <br /> activities, trial welds were performed for each welding machine and welding technician <br /> combination for each type of geomembrane. The trial seam logs are presented in <br /> Appendix K.2.2. As extrusion seaming was performed, proper techniques were verified <br /> including welding angle, grinding, and weld/welding rod cleanliness. The CC!A Monitor <br /> logged the welding machine and welding technician combination, the length of the <br /> seam, the direction the seam was welded, time of seaming, the pre-heat temperature, <br /> and the welding temperature. Destructive test samples were marked during extrusion <br /> seaming and testing is discussed further in Section 3.5.6. All extrusion welded seams <br /> were vacuum tested and is discussed further in Section 3.5.8. The Geomembrane <br /> Extrusion Welding Summary is presented in Appendix K.4. <br /> 3.5.6. Geomembrane Destructive Testing <br /> During welding activities destructive test samples were marked for every 500 linear feet <br /> of seam for each welding type and each welding machine/welding technician <br /> combination. A 24-inch long by 12-inch wide sample was cut from the seam centered on <br /> the seam lengthwise. The sample was then cut in two halves. One half was archived by <br /> the CC+A Monitor to be tested later, if necessary. Ten 1-inch coupons were then cut from <br /> the remaining sample half. Five coupons were tested for shear strength and five <br /> P:\Projects\0106.032 VLF2 Phase 2 CQA\J-REPORTS\ROC Report 1\Cert Report-Phase 2A Part 1\475.0106.032 CCV PHASE 2A Part 1 <br /> ROC REPORT.docx <br /> Page 16 <br />