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<br />-3- <br />In response to Division adequacy comments, the consultant amended pages 39.3 <br />through 39.7 of Appendix 4.5-1 to present a comprehensive discussion of slope <br />stability and subsidence relationships on Coal Ridge. The amended application <br />observes that moderate slumping and landsliding is limited to areas "outside <br />and below the anticipated areas of surface subsidence effects." (page 39.5) <br />The Division concurs with that opinion. There appears, however, to be <br />extensive geomorphic evidence that ancient slope movements have occurred <br />throughout large portions of the slopes on the northeast face of Coal Ridge. <br />On pages 41.1 and 41.2 of the amended Appendix 4.5-1, the consultant describes <br />a proposed visual monitoring program which will specifically observe slope <br />characteristics considered indicative of slope movement, such as .surface <br />cracking, movement of large rock blocks and the development of bulging ground <br />near the base of the slope." The amended application's Appendix 4.5-1 also <br />presents a detailed proposed program for mitigation of slope stability <br />problems. Simplistically, in areas where no danger is presented to <br />structures, mine personnel or the public, the applicant proposes to restrict <br />access and visually observe manifested slope instability phenomena. In any <br />areas where a hazard exists to structures, mine personnel or the public, the <br />operator will also, "... as necessary and appropriate, provide slope <br />stabilization techniques". As amended, however, vagueness exists concerning <br />the role of the Division in the decision of whether or not a hazard to <br />structures, mine personnel or the public exists. To avoid possible future <br />confusion the Division deems it appropriate to impose the following <br />stipulation upon permit approval. <br />STIPULATION: <br />THE DIVISION REQUIRES STORM KING MINING, IN THE EVENT THAT ANY SLOPE <br />INSTABILITY IS DETERMINED, BY THE DIVISION, TO HAVE DEVELOPED WITHIN THE <br />AFFECTED AREA, TO COMPLETE, AND SUBMIT TO THE DIVISION FOR REVIEW, AN ANALYSIS <br />OF THE CAUSES AND RESULTANT HAZARDS OF ANY SUCH UNSTABLE SLOPE AREA. USING <br />THIS ANALYSIS, THE DIVISION SHALL DECIDE WHETHER A HAZARD IS REPRESENTED BY <br />ANY SPECIFIC SLOPE MOVEMENT EVENT AND WHETHER A SLOPE STABILIZATION PROGRAM <br />SHOULD BE DEVELOPED AND IMPLEMENTED BY STORM KING MINING. <br />In response to Division adequacy comments, the consultant significantly <br />amended the discussion of the proposed visual monitoring program contained in <br />the original version of Appendix 4.5-1. The amended visual monitoring <br />program's description has been expanded to include observations designed to <br />determine development of sinkhole collapse and slope instability. The <br />consultant also amended the application to state that monitoring, both visual <br />and survey, would continue until cessation is approved by the Division, in <br />writing. <br />The amended application also proposes a survey subsidence monitoring program. <br />The original application proposed the installation of one linear set of <br />widely-spaced subsidence monitoring monuments, oriented perpendicular to the <br />spine of Coal Ridge. Considering the importance of verifying subsidence <br />projections contained within the application (Appendix 4.5-1), reliance upon <br />