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OVERVIEW AND BACKGROUND OF THE RECLAMATION PROJECT <br />The Colowyo Mine (Colowyo) continues to demonstrate its commitment toward <br />contemporaneous reclamation and bond release by completing a multi -year, <br />large scale, reclamation project on the West Pit Permanent Valley Fill within <br />West Pit operation. The West Pit Valley Fill (West Pit Fill) project commenced <br />initially during the box cut of the West Pit in 1995. The valley fill was permitted <br />as a permanent valley fill to compensate for extra overburden material that was <br />schedule to be removed from the West Pit during the initial phase of mining. <br />After topsoil stripping occurred and prior to any out -of -pit material being placed <br />in the valley fill, Colowyo constructed a permanent rock lined under -drain in the <br />heart of the valley. This drain allowed a location for water disseminating <br />through the fill to collect and drain properly to safeguard the long term stability <br />of the fill. Once this drain was complete the first overburden material was <br />placed in the valley. The valley fill was constructed to tight tolerances dictated <br />by approved geo- technical specifications which also guaranteed its' long -term <br />stability. <br />As the face of the fill neared the approved post -mine topography (PMT), it was <br />regraded to the approved elevation, topsoiled, and seeded with the approved <br />reclamation seed mix. Material placement, regrading, topsoil, and seeding have <br />occurred on the valley fill from 1995 to its final completion in the fall of 2013. <br />Since reclamation efforts begun on the West Pit Fill, 78.5 acres on the valley fill <br />have been Phase I released, 73.3 acres Phase II released, and 55.1 acres Phase III <br />released to date. <br />DESCRIPTION OF THE RECLAMATION PROJECT <br />The culmination of excellence in this reclamation project occurred from 2011 to <br />the fall of 2013 when Colowyo employed several differing strategies to finalize <br />the reclamation efforts on the West Pit Fill. Colowyo understood the immense <br />size of the project early on, and the permitted schedule indicated the West Pit <br />Fill had to be reclaimed by the end of the year in 2013. Planning and strategy for <br />a project of this size was developed in late 2010, and in 2011 Colowyo <br />commenced backfill and grading with a Bucyrus -Erie 800W dragline. A dragline <br />for most purposes would not be considered an ideal machine to complete <br />