2009-05-22_PERMIT FILE - C1981044A (6)

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Subsidence Barriers. Although no subsidence barriers are anticipated during the next Five years of mining, EC plans to protect the State Highway 13 from subsidence as indicated on the Life-of-Mine Plan Map (Map 22). This will be done by leaving pillars in place, in addition to keeping the highway outside of the angle of draw. Current estimates of angle of draw of subsidence as well as experience gained within the next five years will be used to help design the subsidence barriers. Further information on subsidence and subsidence effects on renewable resources are detailed later in this section. The projected annual production from the No. 5 mine was approximately 2.5 million tons, while the projected production of the No. 6 mine is approximately 4.0 million tons annually. This includes historic No. 5 Mine production. Economic and marketing constraints will eventually dictate the total annual production from the mines. The anticipated annual production from the mines is presented on Table 53, Eagle Mines Annual Coal Production. Sections may be added or deleted from any part of the mine to meet production requirements so long as the operational activities are within the permit boundary and the performance standards are met. The system set forth in this permit represents the best engineered estimates of operation, but in no way restricts the number of sections used, location of sections or production tonnage to be produced in the permit area. Mine Sequence As currently envisioned by EC, Longwall mining will continue in the No. 6 mine until completion of all longwall panels. Reserves from the No. 5 mine have been exhausted and no further production is planned from this mine. The sequence of major development and mining events are shown graphically on the No. 5 Mine Plan Map (Map 23) and the No. 6 Mine Plan Map (Map 24). The general sequence of mining is described below. ' As stated above, all longwall and development mining has been completed in the No. 5 Mine. Only the SA portal remains from the No. 5 Mine, as it provides access via rock slope, to the No. 6 Mine. As described above, longwalling is a full extraction method of mining; therefore, caving and most subsidence have occurred directly behind the longwall machine. During late 1986 and 1987, although there will be no full extraction longwalling occurring in the No. 6 mine, development will occur in preparation of moving the longwall machine. In the No. 5 mine, the longwall machine extracted the panels from East to West, although the mining operation proceeded in a northerly direction. The sequence of mining in the No. 5 mine will repeat itself through the first six panels of the No. 5 mine. Once the panels are mined out in the No. 5 mine, the longwall system over a period of 1 to 2 months will be moved and installed in panel No. 1 of the No. 6 mine. With completion of mining of the No. 5 mine, approximately 8 million tons of coal have been removed. The first panel to be mined at the No. 6 mine will be panel No. 1, Longwall mining will proceed in approximately a southeast to northwest direction in panel No. 1. Longwall mining and panel development will then proceed as shown on the No. 6 Mine Plan Map (Map 24). Like the No. 5 mine, the longwall machine will proceed in an east to west direction although general mining sequence will proceed in a northerly direction. In order to help the Division visualize how a longwall panel operates, a longwall panel is presented in Figure 47, Typical Longwall Panel. The current five year permit term will conclude in 1998 with longwall mining in Panel No. 3 and development mining in panel No. 4 of the No. 6 mine (Map 24). Mining, as described, will continue for the life of the mine in the "E" coal seam of the No. 6 mine. Details of the life-of-mine sequencing is shown graphically on the Life-of-Mine Plan Map (Map 22). Permit Revision 04-34 2.05-4 Revised 7/2/04