2009-07-07_REPORT - M1980244 (6)

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Cripple Creek & Victor Gold Mining Company Cresson Project ameO Quality Assurance Monitoring and Test Results Load Out Bin Relocation July 7, 2009 2.5 LOB Liner System A single geomembrane composite liner system was installed on the LOB pad. The composite liner system on the LOB pad consists of a minimum of 12 inches of compacted SLF overlain by a single layer consisting of both 100 -mil single sided texture and 80 -mil smooth LLDPE geomembrane. The installation of the geomembrane in the LOB began on April 15, 2009 and was completed on April 28, 2009. Ames anchored geomembrane at the limits of the LOB in a 3 feet deep by 2 feet wide anchor trench. Ames backfilled the anchor trenches with suitable anchor trench backfill material. Ames placed anchor trench backfill in maximum 12- inch -thick compacted lifts. Anchor trench backfill was compacted with a hand - operated, 500 -lb. vibratory compactor and "Jumping Jacks." The LOB geomembrane liner overlapped and was extrusion welded to the Phase IVc VLF liner system, as detailed in IFC Drawing No. A250. The geomembrane as -built panel layout is shown on Figure 6. Upon completion, a 2 -foot layer of DCF was then placed over the geomembrane. 2.6 Drain Cover Fill Ames began placing DCF in the LOB on April 29, 2009 and completed placement on May 6th, 2009. Ames processed DCF from April 10th, 2009 to April 14th, 2009 and from May 4th, 2009 to May 5th, 2009 by screening crushed Cresson Ore over a vibrating one and one -half inch screen to remove oversize material from the borrow source. Ames placed approximately 3,224 cubic yards of DCF on the LOB pad. DCF was placed in a minimum 2 -foot thick lift over the geomembrane and in a 10 -foot thick lift where 777 haul trucks traveled over the geomembrane. During fill placement, PVC grade markers were placed at grade breaks and on a maximum 50 -foot by 50 -foot grid. After DCF placement, PVC grade markers were removed, and Ames performed any additional grading required. Ames placed DCF in an uphill direction on any slopes steeper than 4H:1V. An isopach showing thickness of the DCF is shown on Figure 7. SIPROJECTS\1125E CCV COXH3 - CONSTRUCTION\LOB CERT REPORT\REPORT BODY\LOB CERT REPORT 2009.07.01.DOC 8