2015-08-31_GENERAL DOCUMENTS - C1981010

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With the approval of PR6, Task No. 025 of the reclamation cost estimate included a cost to bring material from Horse Gulch Fill back to the pit area. The Division met with Trapper on November 12, 2013 to discuss the adequacy review items raised during the review of PR7 and the reclamation cost estimate. During this meeting, Trapper presented to the Division that the backfilling and grading operation for the K Pit has been modified and the updated plan to backfill K Pit with PR7 allows for a significant reduction in the cost estimated to backfill and grade this pit to the post mine topography. According to Trapper, at the time that PR6 was submitted, approximately 5.6 million cubic yards of material was estimated to be hauled back from the Horse Gulch Fill (task No. 025 in the PR6 cost estimate) to assist with the backfill of K Pit by the truck/loader operation. After the PR6 submittal and the performance bond was estimated, a number of changes were made that impacted the design, volumes, and methods of backfill in K Pit. This resulted in less out-of-pit spoil placed in the Horse Gulch Fill, and Trapper demonstrated with TR106 that a buttress fill on the north limits of K Pit was no longer needed. Thus less material was needed to be hauled back from Horse Gulch Fill and further reduced available dump room for the spoil. To address this issue, a plan was developed to allow the dragline operation to remove the M seam and Q seam interburdens (that were previously planned to be removed by the truck/loader operation and taken to the Horse Gulch Fill) and to place more material in K Pit. As a result of the modified backfilling and grading plan, the liability estimated to backfill K Pit is substantially less than was originally projected with PR6. This accounts for the reduced reclamation liability amount determined for PR7. 20 Trapper MineJuly 9, 2013