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Memo to Dan Mathews Deserado Mine TR-48, Subsidence page 2 I have a few specific concerns and comments which follow. For ease of location, I have identified my comments by application section, page, and paragraph. § III.A.7.b Subsidence Control (pages III-11 & III-12) BME discusses the general benefits of longwall versus room-and-pillar mining in this application section. BME states; "No truly long-term subsidence hazards are associated with longwall mining". I believe BME intends to state that subsidence hazards associated with longwall mining are all manifested in a fairly short time frame. In fact, some of the impacts of longwall mining, such as ground cracking in the peripheral areas around the subsided panels, can remain in effect for relatively extended periods of time (decades) following the cessation of actual ground movement. § III.A.7.c Subsidence Prediction (pages III-12 through III-14) This section and associated table III-1 present the methodology and results of the basic NCB-style vertical subsidence and strain predictions above the D-Seam and a portion of the proposed B-Seam mining. Table III-1, however, only contains predictions for panels LW-1 B through LW-8B. These are the panels projected to be extracted through the year 2023. This is a long period, approximately 25 years, and more than satisfies the requirements for permit submittal. Coincidentally none of these first eight projected B-Seam panels happen to be superimposed beneath D- Seam panels. However, the mine plan as depicted on Maps 119 (D-Seam) and 120 IB-Seam) will eventually include superimposed D-Seam and B-Seam workings. Only three depicted B-Seam panels, the unnamed panels in Section 35 bearing only the dates 2012, 2013 1 nd 2014, which I assume are depicted on Map 120 for "illustrative" purposes, will eventually be superimposed beneath unnamed D-Seam panels depicted as outlines in Section 35 on Map 1 19. However, no dates or panel labels are included on Map 1 19. The Operator may have intended to delete these panels from the D-Seam mine plan. The subsidence predictions presented in Table III-1 appear to be appropriately completed. My point is that no discussion or subsidence predictions of the additive effects of subsidence of superimposed mine workings in the D-Seam and underlying B-Seam is presented anywhere in the application. Therefore, the application's subsidence prediction can be found adequate for those panels predicted, i.e. all of the D-Seam workings and longwall panels LW-1 B through LW-8B within the B- Seam. However, predictions have not been presented for the three B-Seam