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Mine Access • No. 5 Mine. Currently, access to and ventilation of the No. 5 Mine is provided by the existing No. SA portal as shown on the No. 5 Mine Plan Map (Map 22). Previously, both No. 5 and No. SA were used for ventilation and the transport of men and materials. The No. SA portals has a coal transport conveyor connected to the outside coal handling facilities. The overland belt connects the SA Portal to the coal stockpile located at the surface facilities in the Williams Fork River valley. No. 6 Mine. Access to the No. 6 Mine is from within the existing areas of the No. 5 Mine, as shown on the No. 6 Mine Plan Map (Map 23). The access is from just inside the SA portals consisting of three (3) rock tunnels and two (2} seam to seam air shafts located approximately 1500 feet inside the portals. This access resulted in no new surface disturbance. Also, a shaft will be installed above the No. SA portal highwall. This shaft will connect both seams with the surface. The surface location is within the existing sediment control system and is on previously disturbed ground. The approved technical revision for this activity is included as Exhibit 40,E -Seam Access & Development. A short rock slope runs northwest to meet the main and west entries. The No. SA portal and surface facilities will be used for the life of the No. 6 Mine. The coal transport system associated with the No. SA portal will be used. The anticipated timing for the first set of ramps and seam to seam shafts is 1986 and 1987. The second set of ramps and are scheduled for about 1989. The shaft to the surface will be installed at a later date. Longwall Mining As stated earlier in this section, longwall mining is the primary extraction method useda[ the Eagle No. 5 and Eagle • No. 6 mines. In the area shown on the No. 5 Mine Plan Map (Map 23) and [he No. 6 Mine Plan Map (Map 24), continuous miners are used to develop panel entries and outline a coal block. The longwall mining unit is then used to fully extract the coal block in retreat. Atypical cross section of the longwall equipment is shown on Figure 45, Longwall Face Cross-Section Equipment. RAG EC uses the retreat method of longwall mining that consists of two sets of parallel entries driven in the coal seam separated by a distance equal to the longwall face width. When these sets of entries have reached a predetermined distance or boundary, they are connected to form the face, which is then retreated by extracting the coal. A large block, approximately 600 to 800 feet wide and 3,000 to 7,000 feet long, is developed in the coal seam. The coal is then continually extracted by taking predetermined slices (or cuts) along the full width of the block. The cutting of the coal is achieved with ashearer-loader, traversing the face. The coal that is cut from the face is transported from the face by a chain conveyor. The coal is then fed to a stageloader, which is located in the entry adjacent to, and at right angles, to the chain conveyor. The stageloader feeds the coal onto a belt conveyor, which delivers the coal onto the main coal clearance system. A schematic of the longwall system is presented on Figure 46, Typical Three Entry Longwall Development. As the slices or cuts are taken, the newly exposed roof is supported by roof canopies of a hydraulically operated powered support system, During this operation, the previously supported roof furthest from the face line collapses behind [he roof support system. This cycle of operation is repeated until the entry panel has been extracted. The longwall equipment is then transferted to the next longwall panel. A list of the major equipment used in the longwall development and mining system is presented in Table 52, Longwall Equipment List. . In the event general underground mining activities encounter adverse conditions, blasting may be required. The amount of blasting that may be required is insignificant to the operation. If blasting is necessary, it will be performed using a permissible powder and in accordance with Mine Safety and Health Administration (MSHA) regulations. MidTerm Response ~lPPR.n~~n ", ^ , ~ 2002 2.05-2 ~~.~~ Revised 12/05/01