2014-02-07_REPORT - M1980244 (7)

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Cripple Creek & Victor Gold Mining Company Mill Site Earthworks Project Final Report Quality Assurance Monitoring & Test Results January 31, 2014 ameO panels deployed in 2011 for the Phase IVc Berm Modification below the Mill Site Earthworks footprint. AMEC marked the panel designation and roll number directly on each panel after it was deployed. The geomembrane record drawing, showing the Project geomembrane panel layout and destructive testing is presented as Record Drawing No. 4 of 4 in Appendix A. During geomembrane deployment, AMEC measured sheet thickness with digital callipers. Sheet thickness was measured at five random locations along the edge of each geomembrane panel. The average thickness specified for the 80 -mil geomembrane was 80 mils. Project Specifications for 80 -mil geomembrane required that the average of the five thickness measurements be no less than the 80 mils, and that no individual measurement be less than the nominal thickness minus 8 mils (i.e., 72 mils). The thickness monitoring provided by AMEC indicated that all of the panels met or exceeded project requirements. AMEC personnel measured deployed panel lengths using a measuring wheel. Recorded lengths were approximate, and do not reflect any trimming or adjustments made for final placement or anchor trench lengths. AMEC personnel observed the surface of each deployed panel and logged any penetration defects and marked them on the panel. Section 6.5 provides further discussion of repairs. AMEC confirmed the overlap of each panel with adjacent panels was sufficient for seaming; any insufficient panel overlaps were logged as defects and marked for correction. Ames surveyed all panel intersections and destructive seam sample locations. Using these points, AMEC prepared the geomembrane panel layout, Record Drawing No. 4 of 4, in Appendix A. The Project LLDPE geomembrane deployment observations are presented in Appendix J.1. 6.4 Seaming The double wedge fusion weld was the principal seaming method employed by Lone Star for this project. Lone Star fusion seamed (welded) geomembrane on the same day that it was deployed. Lone Star used extrusion welds for seaming where the 80- mil LLDPE geomembrane was tied into 80 -mil LLDPE geomembrane at the temporary anchor trenches, for repairs, and where conditions were unfavourable for fusion welding (e.g., sharp corners). AMEC observed trial seam tests; monitored seaming equipment temperatures and speed; and provided visual observation of the seaming procedures. The entire lengths of all seams, patches, and other repairs during seaming, or shortly after completion, were documented and inspected. 24