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Memo to Dan Mathews Deserado Mine TR-48, Subsidence page 3 longwall panels which underlie the three unnamed D-Seam panels depicted in outline form on Map 1 19. Therefore, no approval can be granted by the Division for development or extraction associated with those panels. In addition, no decision can be rendered and no approval granted by the Division regarding the acceptability or the impacts of superimposed extraction within the D-Seam and B- Seam, if and when it is proposed. While experience in the D-Seam workings has demonstrated that the general impacts of single seam mining can be controlled by the approved subsidence control plan, the magnitude of vertical subsidence and resulting horizontal strains will be significantly larger and mechanical and hydrologic impacts may require different methodology to control. I repeat, however, that the information provided is adequate to approve the subsidence control plan regarding non-superimposed mining within the D-Seam and B-Seam panels LW-1 B through LW-8B. §III.A.7.d Horizontal Strain Prediction (pages III-14 & III-15) This section ends with a statement that cracks at the surface will tend to fill naturally and rapidly after mining ceases. As I stated above, I believe that cracks within the peripheral area of longwall mining and above the chain pillars may tend to take longer to develop, may be wider and deeper, and will tend to remain open longer, then the more transient cracks directly above the panels. In general this should not be of significant additional concern, and the general mitigation plan of filling them should suffice. I would recommend that particular attention be paid to the area within Scullion Gulch immediately above the southeastern corner of panel LW-1 B. Some gradient reversal requiring minor channel regrading might also be expected at this location. §III.A.7.h Damage Mitigation (page III-20) In nineteen years of observing permit areas effected by subsidence I have yet to witness one head of livestock or wildlife injured by subsidence related impacts. If BME were to implement its ultimate mitigation plan of fencing livestock out of impacted surface lands, I assume the grazing lease holder would require reimbursement for lost grazing potential. BME states that its plan has been provided to the BLM for review. Has BLM provided any comment to BME in regard to this mitigation alternative? Similar to my comments above concerning Scullion Gulch, I would expect the