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requirements or highwall reclamation requested or allowed in the permit area. Exhibit D, Post Mine <br />Cross-Sections of the bond release application, provides representative cross-sections showing final <br />topography configuration. <br />The approved Post-Mining Topography Map, Exhibit 20-2 was compared with USGS 7.5 minute <br />Quadrangle Maps of Mount Harris and Dunckley, Colorado to determine if post-mine drainages were <br />constructed in appropriate locations with adequate drainage density. Pre-mining topography was also <br />compazed with the approved Post-Mining Topography Map to verify that regraded slopes achieved <br />AOC. All regraded slopes were inspected and evaluated for erosional stability during the Phase I <br />bond release inspection and routinely during normal monthly inspections. Results of these <br />evaluations are discussed below in Section III Observations and Findings. <br />The final reclamation plan for the Yoast Mine includes retention of numerous postmine drainage <br />channels. To date, the Division has not received requests for retention of sediment ponds or stock tanks <br />as permanent impoundments at the Yoast Mine. One pond, Sediment Pond O11A is located at the east <br />end of the North Pit and was included in the Phase I bond release azea. The Division's findings <br />regarding Pond O11A aze presented below in Section III. <br />The structures approved as permanent facilities in the North Pit were evaluated as part of this Phase I <br />bond release and include Postmine Drainage Channels PM-9, PM-10, and PM-13. The postmine <br />channels are shown on Exhibit 20-2 and certified designs are provided in Appendix 13-12.3 of the PAP. <br />Postmine channels in the North Pit are designed to safely convey the peak discharge from the 10-yeaz, <br />24-hour storm event in accordance with Rule 4.05.3. <br />The Yoast Mine drains to Sage Creek on the west side and to Grassy Creek on the east side. Sage <br />Creek and Grassy Creek aze perennial tributaries to the Yampa River. Armand Draw and Scotchmans <br />Gulch are intermittent drainages which drain from the northern side of the proposed permit azea into <br />Grassy Creek. The Yampa River then flows to the Green River and eventually the Colorado River. <br />Postmine Channel PM-9 and PM-13 flow to Pond O11A which dischazges to Pond 011 and <br />subsequently dischazges to Grassy Creek. Postmine Channel PM-10 flows to Armand Draw which <br />drains to Grassy Creek. <br />6 <br />