2014-02-07_REPORT - M1980244 (7)

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Cripple Creek & Victor Gold Mining Company Mill Site Earthworks Project Final Report ameO Quality Assurance Monitoring &Test Results January 31, 2014 6.4.1 Trial Seam Monitoring Lone Star performed trial seams to monitor the performance of the seaming apparatus and operator under actual site conditions. Each welding operator and his apparatus produced trial seams prior to the beginning of each day's seaming operation, after all work activity stoppages, and in the event that devices were disconnected from power and re- energized. Lone Star cut 1- inch -wide samples (coupons) from each trial seam and tested the coupons with a field tensiometer. Lone Star tested each double wedge fusion trial seam twice for peel adhesion (peel) and once for bonded seam strength (shear). Tests were conducted on fusion welds on both the inner and outer tracks of each peel coupon. Lone Star tested each extrusion trial seam twice for peel and once for shear. AMEC personnel observed trial seam sample testing and documented test results. Tensile testing of each trial seam coupon was observed to verify project yield strengths were met during shear testing and failure did not occur in the weld during peel testing. When trial seams did not meet Project Specifications, AMEC verified the welding apparatus was not used until two consecutive trial seams performed by the same technician /apparatus combination met Project Specifications. The trial seam test results for extrusion and fusion seaming are presented in Appendix J.2. Lone Star used one tensiometer during the project and one spare tensiometer was maintained on site. Tensiometer certifications are presented in Appendix L. Figures 3 and 4 show the codes used to designate passing and failing test results. 6.4.2 Seaming Observations AMEC personnel observed seams before, during, and after welding. Each seam was checked for adequate overlap prior to welding and to verify the seam area was clean and dry. AMEC documented Lone Star personnel performing the seaming and the seaming equipment used. Following the completion of seaming and routine repairs, AMEC checked the full length of each seam to verify no additional repairs were required. In the event additional repairs were needed, AMEC marked the location on the geomembrane, documented the location, and brought the area to the attention of Lone Star. Once Lone Star made repairs, AMEC checked the repair location to verify completion. All seams were inspected for quality and completion. AMEC personnel conducted a final walk through to verify completion of the entire geomembrane system and to identify any additional damage that may have occurred during construction operations. AMEC recorded observations made during seaming. The geomembrane layer and the fusion and extrusion welding met Project Specifications; and a summary is presented in Appendix J.3. 25