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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 /> coupons were tested for peel strength using a tensiometer. The different failure types <br /> and test codes for fusion and extrusion destructive testing are presented on Figures 3 <br /> and 4, respectively. All destructive testing was performed by Tetra Tech in the presence <br /> of the CQA Monitor. Two fusion destructive tests failed within the Squaw Gulch Phase <br /> 2A Part 1 area and the extent of the failure was delineated by obtaining samples before <br /> and after the failed sample. Once the failing area was identified, that portion of the <br /> seam was capped. Fusion and Extrusion Destructive Testing Summaries are presented in <br /> Appendix K.5.1 and Appendix K.5.2, respectively, and the tensiometer certifications are <br /> presented in Appendix M. <br /> 3.5.7. Geomembrane Pressure Testing <br /> Pressure testing was performed to ensure all fusion welded seams had continuity <br /> throughout their entire length. The ends of the seam were sealed and the air channel in <br /> the seam was pressurized using a small air compressor to a minimum of 30 pounds per <br /> square inch (psi), for a minimum of five minutes. A pressure gauge and needle were <br /> used to monitor the air pressure in the seam. If the pressure dropped less than 3 psi, the <br /> opposite end of the seam from the pressure gauge was cut. If the needle dropped, <br /> continuity was confirmed throughout entire seam length and the test was considered <br /> "passing." If a pressure drop of more than 3 psi occurred or the continuity was not <br /> proven, smaller sections of the seam were tested to delineate the failing section of the <br /> seam. All failing seams or portions of seams were repaired and vacuum tested. The <br /> Geomembrane Seam Pressure Testing Summary is presented in Appendix K.6. <br /> 3.5.8. Geomembrane Defects and Repairs <br /> The CQA Monitor constantly inspected the geomembrane for defects from the time it <br /> was deployed until it was covered with DCF. A defect is defined as any item in which a <br /> repair is necessary to create a continuously sealed geomembrane layer. All defects were <br /> marked with a defect number by the CQA Monitor. Repairs were performed using the <br /> extrusion welding method and patches extended at least 6 inches beyond the defect in <br /> all directions. All repairs were assigned a repair number and cross checked with defect <br /> numbers to ensure that all defects were repaired. <br /> All repairs and extrusion welded seams were non-destructively tested using a vacuum <br /> box. The area being tested was covered in soapy water and the vacuum box was sealed <br /> to the geomembrane. A vacuum was pulled over the area for at least 10 seconds and if <br /> no bubbles were present, the test passed. If bubbles were present, the area failed and <br /> was marked as a defect. The repair process would then be repeated for the failing <br /> vacuum test. Vacuum tests overlapped each other by a minimum of 3-inches. The <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 17 <br />