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-6- On pages 41.1 and 41.2 of the amended Appendix 4.5-1, the consultant describes a proposed visual monitoring program which will specifically observe slope characteristics considered indicative of slope movement, such as "... surface cracking, movement of large rock blocks and the development of bulging ground near the base of the slope." The amended application's Appendix 4.5-1 also presents a detailed proposed program for mitigation of slope stability problems. Simplistically, in areas where no danger is presented to structures, mine personnel or the public, the applicant proposes to restrict access and visually observe manifested slope instability phenomena. In any areas where a hazard exists to structures, mine personnel or the public, the operator will also, "... as necessary and appropriate, provide slope stabilization techniques". As amended, however, vagueness exists concerning the role of the Division in the decision of whether or not a hazard to structures, mine personnel or the public exists. To avoid possible future disagreement, our eventual findings will have to impose a stipulation which clearly states that the Division shall review and concur with any decision of whether a hazard is represented by any specific slope movement event and whether a slope stabilization program should be developed and implemented. (3) As mentioned above, in response to earlier Division adequacy comments, the consultant significantly amended the discussion of the proposed visual monitoring program contained in the original version of Appendix 4.5-1. The amended visual monitoring program's description has been expanded to include observations designed to determine development of sinkhole collapse and slope instability. The consultant also amended the application to state that monitoring, both visual and survey, would continue until cessation is approved by the Division, in writing. The application's proposed survey subsidence monitoring program has not been amended in response to our earlier adequacy comments. The application proposes the installation of one linear set of widely-spaced subsidence monitoring monuments, oriented perpendicular to the spine of Coal Ridge. Considering the importance of verifying subsidence projections contained within the application (Appendix 4.5-1), reliance upon only one limited set of monuments is considered imprudent. Our eventual findings should impose a stipulation specifically requiring the installation of a second analogous set of subsidence monitoring monuments at another agreed location on Coal Ridge. (4) It will be important to clearly present the results of the visual and survey monitoring programs at the Coal Ridge No. 1 Mine. The amended application presents no detail regarding the format of the semi-annual subsidence monitoring reports. In the interest of facilitating complete and efficient presentation of the accumulated subsidence monitoring data, our eventual findings could include a stipulation requiring the submission of a proposed subsidence report format within six months following issuance of the permit.