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Cripple Creek&Victor Gold Mining Company ■ <br /> Squaw Gulch VLF Phase 2A Part 2 ■ <br /> Record of Construction Report <br /> 475.0106.032 <br /> September 30,2019 <br /> 3.4.7. Geomembrane Defects and Repairs <br /> The CQA Monitor constantly inspected the geomembrane for defects from the time it was <br /> deployed until it was covered with DCF. A defect is defined as any item in which a repair <br /> is necessary to create a continuously sealed geomembrane layer.All defects were marked <br /> with a defect number by the CQA Monitor. Repairs were performed using the extrusion <br /> welding method and patches extended at least 6 inches beyond the defect in all <br /> 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 vacuum <br /> test. Vacuum tests overlapped each other by a minimum of 3 inches.The Geomembrane <br /> Defect/Repair Summary, including vacuum testing logs, is presented in Appendix J.7. <br /> 3.4.8. Geomembrane Acceptance <br /> Prior to DCF placement,the geomembrane was accepted by Tetra Tech,Tezak,CC&V, and <br /> the CQA Monitor. All CQA logs and survey data were thoroughly reviewed ensuring that <br /> all aspects of the geomembrane installation were performed in accordance with project <br /> Technical Specifications.Geomembrane Acceptance Forms are presented in AppendixJ.8. <br /> 4. PROJECT DEVIATIONS <br /> Throughout construction, the following deviations from the Design and IFC Drawings were <br /> approved by the Engineer of Record: <br /> ➢ Several localized grading, underdrain alignment and HVSCS alignment changes were <br /> made throughout construction in order to better accommodate the actual site conditions. <br /> The grading changes were minor and are presented in the Record of Construction <br /> Drawings. <br /> IFC Drawings A60 and A62 indicated that a fusion weld should be used between the <br /> phased geomembrane connections; however, the use of extrusion welding was also <br /> approved. <br /> The Engineer of Record accepted the substitution of the CBR Puncture Value test (ASTM <br /> D6241) for the Puncture Value test (ASTM D4833) as reported/tested on the geotextile <br /> manufacturing certification sheets. <br /> P.\Projects\Cert Report-Phase 2A Part 2\475.0106.032 CCV PHASE 2A Part 2 ROC REPORT.docx <br /> Page 14 <br />