2009-09-14_GENERAL DOCUMENTS - C1981019

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Five valley fills have been permitted for the disposal of excess spoil. There are three valley fills that are already constructed. One valley fill is in the Streeter draw at the north edge of the East Pit, one adjacent to the Taylor Draw northwest of the West Pit and one in a sub-drainage along the West Fork of Goodspring Creek in Section 16. Both the Streeter Fill and the Section 16 Fill have undergone a Phase II Bond Release. As such, with the approval of Technical Revision 64 (approved on 17 October 2006) the requirement for quarterly inspections of the fills has been terminated. Two new valley fills will be constructed with the approval of Permit Revision 02 for the disposal of the initial box-cut spoil for the South Taylor Pit. The West Taylor Fill will be constructed in the West Fork of upper Taylor Creek and the East Taylor Fill will be constructed in the East Fork of upper Taylor Creek. Colowyo has started construction on the East Taylor Fill. This fill has three minor forks of the drainage that come together to form the East Fork of upper Taylor Creek. Each of these inree forks will 'nave a separate underarain. Coiowyo has constructed underdrains in two of the three forks (named the C-C' and B-B' underdrains). The remaining underdrain is not yet completed (named the A-A' underdrain). The current operations in the South Taylor Pit are disposing of excess spoil in the C-C' underdrain area of the East Taylor Fill. Once the C-C' area has been filled, Colowyo will move to the B-B' and A-A' underdrain areas of the fill for excess spoil disposal. Topsoil Topsoil performance standards are found in Section 4.06 of the PAP (Volume 1 for the East Pit, West Pit, Section 16 Pit, Facilities Area and Gossard Loadout and Volume 12 for South Taylor). Additional information on the soil types can be found on Maps 5, 5A, 5B, 5C and 6 of the Permit. Eighteen inches of topsoil was replaced on all graded sites through 2005 except for approved exceptions. One exception is the Section 11 Pit; where 12 inches of topsoil was placed (PAP, page 4.06.4). With the approval of Technical Revision 62 on 29 May 2006, the topsoil replacement depth for all post 2005 remaining reclamation in the East Pit, West Pit, Facilities area and Gossard Loadout was reduced to eight inches. The topsoil replacement depth for the South Taylor Pit, the West Taylor Fill, the East Taylor Fill and all additional disturbances associated with Permit Revision 02 will be 12 inches. Revegetation Native and introduced forbs and grasses will be drill seeded or broadcast seeded (on steep slopes). Shrub and tree species are also drill seeded or broadcast seeded, based on terrain. Revegetation efforts will be monitored to determine vegetative success as described in Section 4.15 of the PAP. Chisel plowing and terrace or contour furrows are the preferred methods of seed bed preparation. Mulching is not in general use at the Colowyo Mine. Proposed Decision and Findings of Compliance 14 September 2009 Permit Renewal 05 Page 29