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y <br />3 <br />Exhibit 4.7-5 of the Coal Ridge permit includes a stability analysis of the terrace <br />outslopes which indicates a minimum static safety factor in excess of 1.3. The <br />analysis was conducted by a registered professional engineer. Adequate erosion <br />control is assured by a very thorough and consistent cover of vegetation on the <br />outslopes which has become established since the mine benches were first <br />constructed ten years ago. The vegetative cover consists of a mixture of native and <br />introduced grasses, as well as sage brush plants which are over four feet tall. Photos <br />taken by OSM and Division inspectors reveal that the configuration and the <br />vegetative cover of the terrace outslopes resemble the surrounding area enough that <br />the outslopes are difficult to discern from several vantage points on and near the <br />mine. The reclaimed topography and configuration of the site resemble the alluvial <br />valley and terrace configuration of adjacent areas. <br />As part of its proposed decision to deny the permittee's request for Phase I bond release, <br />the Division required the permittee to address six concerns identified by the Division during <br />and after the bond release inspection. One of those concerns was the relevancy of one of <br />the assumptions used in the stability analysis of the outslopes. Specifically, the analysis in <br />the permit assumes no surface water runoff over the face of the outslopes. In light of a <br />small surficial failure on one of the outslopes, and the possibility that surface runoff may be <br />directed over portions of the outslopes following redistribution of topsoil, the Division asked <br />the permittee to reassess the outslope stability. The permittee has proposed cutting <br />outslopes back to 3h:ly and armoring those areas where surface runoff may affect the <br />outslopes. These plans, as well as responses to the other five concerns raised by the <br />Division, are presently being reviewed. <br />In summary, the Division approved a reclamation plan for the Coal Ridge Mine which <br />specifies the site be reclaimed to approximate original contour, as required by Colorado <br />regulations. That plan incorporates the use of terraces which compliment and enhance the <br />post-mine land use and meet all of the relevant regulatory performance standards. The <br />Division was neither arbitrary or capricious in approving the reclamation plan. Therefore, <br />there is no violation of Rule 4.14.2, as alleged in TDN 95-020-174-003. <br />We believe this teller constitutes an appropriate response to TDN 95-020-179-003. If you <br />have any questions or need additional information, please contact me. <br />Sincerely, <br />Susan J. McC non cc: Barbara Pavlik <br />Coal Program Supervisor Larry Routten <br />m:\coal\Ipr\082995 <br />