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Some issues with the ditches were observed: <br />• In the North Tributary East Pit Ditch, there is a bare spot below the NTEP Pond. This <br />reach of the channel should have riprap armoring per the design in the PAP. However, <br />there is no erosion in the channel. <br />• The Prospect Ditch channel reach between the ponds (PD1 and PD2) is not well shaped <br />and is eroded. Below the lower pond (PD1) riprap is sparse in some areas. <br />• In Taylor Ditch, rock needs to be moved from the middle of the channel to the sides in <br />some areas. In other areas (near the bottom) riprap is sparse in the middle of the channel, <br />and little to no vegetation has grown in the channel. <br />• In Taylor Tributary Ditch, there are areas with sparse riprap in the middle of the channel. <br />However, this ditch is well vegetated. <br />These issues have been addressed by Colowyo: <br />• Regarding the North Tributary East Pit Ditch, Colowyo has shown with SEDCAD <br />modeling that it is sufficient that the reach in question is lined with vegetation rather than <br />riprap. This was done with TR -97. <br />• Regarding Prospect Ditch, the channel reach between the ponds has been re- shaped. For <br />the reach below the PD pond, it has been shown that a vegetation lining is sufficient for <br />stability (see TR -97). <br />• In Taylor Ditch, rock has been moved from the middle of the channel to the sides in the <br />areas in question. <br />• Regarding Taylor Tributary Ditch, Colowyo has shown with SEDCAD modeling that it is <br />sufficient that the reach in question is lined with vegetation rather than riprap. This was <br />done with TR -97. <br />In addition to the channels discussed above, the Division inspected stock tank ponds and contour <br />ditches. The following stock tank ponds were observed: EP 1, NTEP 1, PD 1, and PD2. All <br />embankments were 10 feet in width or greater (per design), and the slopes were all <br />approximately 3:1 (H:V). They all appeared stable and had riprap lined spillways. No problems <br />were identified with contour ditches. <br />Summary and Conclusions <br />The Division has completed its review and evaluation of the SL -06 Phase I Bond Release <br />application submitted by Colowyo for the Colowyo Mine. The Division proposes a partial Phase I <br />Bond Release on 692.37 acres. The Division is also proposing Phase I bond release for sections of <br />post- mining drainage channels as well as stock tank ponds that fall within these 692.37 acres. <br />Based upon a review of the mine permit, the applicant's bond release application, and site <br />inspections, the Division finds that Colowyo has completed backfilling, grading, and drainage <br />reestablishment at the Colowyo Mine for which Phase I Bond Release was requested in accordance <br />with the approved reclamation plan. The reclaimed areas included within the SL -06 bond release <br />request have been restored to the approximate original contour of the pre- mining landscape. <br />Proposed Decision and Findings of Compliance April 2013 <br />Partial Phase I Bond Release SL -06 Pagel <br />