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Cripple Creek & Victor Gold Mining Company November 9, 2006 <br />Mr. Gary Goodrich -2- 063-2269 <br />2006 Tertiary Pipeline Extension <br />In July, 2006, the 6-inch PCPE pipe was extended approximately 750 feet to further augment solution <br />drainage along the northwestern edge of the VLF. The location of the 6-inch PCPE pile extension <br />completed in 2006 is shown on Figure 1. This augmentation of the VLF solution collection system <br />was conducted in part to mitigate saturation that was observed after heavy rains where flow in the <br />drain cover fill (DCF) encountered zones of compaction which resulted in saturation and pooling near <br />the perimeter of the VLF. The 6-inch pipe was installed by carefully trenching (hand excavating the <br />lower 6 inches) into We DCF, placing the PCPE pipe into the trench at the primary liner, and <br />backfilling the trench with DCF. Photographs of this extension are provided as Figures 2 through 5. <br />During the installation of the PCPE pipe, the VLF liner was damaged in two locations, one by the <br />bucket of the backhoe, and one by a rock. The small defects were repaired by placing a patch over <br />the damaged area. The patch was welded to the primary liner via extrusion welding, as shown on <br />Figure 6. The two patches were then vacuum tested after welding. CCBcV personnel completed the <br />liner patching and testing. The vacuum test sheet for the patch is provided as Attachment 1. Golder <br />inspected the area after installation of the 6-inch PCPE pipe, reviewed the repair documentation, and <br />approved the installation. <br />Closure <br />The modifications to the Phase IVc solution collection piping system were completed by CC&V <br />personnel and inspected and approved by Golder. The modifications will augment solution collection <br />along the northwestern edge of the VLF and therefore improve primary containment in the Phase IVc <br />area. <br />Golder appreciates the opportunity to provide technical services for the Cresson Project. Please <br />contact the undersigned with any questions. <br />Sincerely, <br />GOLDER ASSOCIATES INC. <br />.~ <br />Brent R. Bronson, P.E. <br />Principal <br />34969 <br />-~9~0~ <br />,vKUewumv,vou~reowomvanwrK,.=xws:uuourwaw,wsmrGolder ,4ssociates <br />