2016-10-21_REPORT - M1980244 (31)

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Cripple Creek & Victor Gold Mining Company Squaw Gulch VLF Phase 1 Completion Record of Construction Report 475.0106.006 October 14, 2016 P:\Projects\0106.006 CC&V CQA and EDS\J‐REPORTS\ROC Report\475.0106.006 CCV PHASE 1 ROC REPORT ‐ FINAL161014.DOCX Page 15 and 4, respectively. All destructive testing was performed by ECA in the presence of the CQA Monitor. No destructive tests failed within the Squaw Gulch Phase 1 Completion area. Fusion and Extrusion Destructive Testing Summaries are presented in Appendix J.5.1 and Appendix J.5.2, respectively, and the tensiometer certifications are presented in Appendix L. 3.4.6. Geomembrane Pressure Testing Pressure testing was performed to ensure all fusion welded seams had continuity throughout their entire length. The ends of the seam were sealed and the air channel in the seam was pressurized using a small air compressor to a minimum of 30 pounds per square inch (psi), for a minimum of five minutes. A pressure gauge and needle were used to monitor the air pressure in the seam. If the pressure dropped less than 3 psi, the opposite end of the seam from the pressure gauge was cut. If the needle dropped, continuity was confirmed throughout entire seam length and the test was considered “passing.” If a pressure drop of more than 3 psi occurred or the continuity was not proven, smaller sections of the seam were tested to delineate the failing section of the seam. All failing seams or portions of seams were repaired and vacuum tested. The Geomembrane Seam Pressure Testing Summary is presented in Appendix J.6. 3.4.7. Geomembrane Defects and Repairs The CQA Monitor constantly inspected the geomembrane for defects from the time it was deployed to DCF placement. All defects were marked with a defect number by the CQA Monitor and consisted of any item which a repair was necessary to create a continuously sealed geomembrane layer. Repairs were performed using the extrusion welding method and patches extended at least 6‐inches past the defect in all directions. All repairs were assigned a repair number and cross checked with defect numbers to ensure all defects were repaired. All repairs and extrusion welded seams were non‐destructively tested using a vacuum box. The area being tested was covered in soapy water and the vacuum box was sealed to the geomembrane. A vacuum was pulled over the area for at least 10 seconds and if no bubbles were present the test passed. If bubbles were present the area failed and was marked as a defect. The repair process would then be repeated for the failing vacuum test. Vacuum tests overlapped each other by a minimum of 3‐inches. The Geomembrane Defect/Repair Summary, including vacuum testing logs, is presented in Appendix J.7.