2012-04-20_REVISION - C1981012 (2)

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Page 5 of 7 21. Based on the mine plan shown on proposed Map 3, it appears as though NECC is proposing to pull pillars in the Allen Seam under several houses and other structures, as shown in details 44- 47 on the Map 20 series. If this is, in fact, the plan, NECC will need to address the subsidence control and mitigation plan for these structures. In addition, NECC will need to contact the property owners and inform them of the plan to subside their houses and other structures within six months of any planned mining, pursuant to Rule 4.20.0. If the proposed mine plan is no correct and NECC is not planning on pulling pillars in the Allen Seam under the houses and other structures in details 44 -47 on the Map 20 series, please correct Map 3 as necessary. 22. Based on the mine plan shown on proposed Map 3, NECC is planning on mining right up to the permit boundary, including pulling pillars, in several locations in both the Allen and Blue Seams. Please provide the Division with the proposed angle of draw for each of these seams and provide the Division with written verification that there will be no subsidence outside of the permit boundary. This information should also be included in the subsidence monitoring and control plan update, which is being requested in questions 34 -36 below. 23. The proposed mine plan map, Map 3, shows the rough timing of mining in one year blocks. Pursuant to Rule 2.05.3(2)(b), please provide more detailed information regarding the timing of mining on Map 3. Additionally, the timing is difficult to see. Please make the timing of mining more clear on Map 3. 24. Proposed Map 3 shows corridors under gas pipelines and roads where pillars will not be pulled. This will lead to a no subsidence mine plan for these areas. However, based on the fact that NECC will be pulling pillars on both sides of these corridors, there will possibly be some subsidence along these corridors, based on the projected angle of draw. Since there will be pillars pulled on each side of these corridors, it is possible that the two projected angles of draw (one on each side of the corridor) could cross -over. This could lead to subsidence along the gas pipeline and road corridors. Please provide the Division with the projected angle of draw for the subsidence for each coal seam to be mined and please discuss the possibility of subsidence along these corridors that could be caused by pulling pillars on each side of the corridors. If it is determined that these corridors are not wide enough to prevent subsidence, please correct proposed Map 3 as necessary. 25. Proposed Map 3 includes all active gas wells within the permit area, which will be protected with a 150 -foot barrier pillar. Please show all inactive and abandoned wells on Map 3 as well and please include a barrier pillar to protect these structures from damage from subsidence and mining activities. 26. Please provide the Division with the date of the last structural inventory (gas well and pipeline corridor search). If this was not a recent search, please ensure that no new wells or pipelines have been drilled or installed since the date of the last search. Please update proposed Map 3 accordingly if any new gas wells or pipelines have been added to the permit area. Please add a note to proposed Map 3 indicating when the last structural inventory was completed. Rule 2.10 — Maps and Plans 27. With the submittal of PR -04, NECC has provided numerous maps with the updated mine plan and permit boundary. However, there are maps in the permit document that show the permit New Elk Mine PR -04 PAR Letter 5 20 April 2012