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Room and Pillar Minine <br />Due to uncertainties concerning marketing, economics, and availability of the longwall system, EC reserves the right <br />to reemploy room and pillar mining at any given time and any given location of the No. 5 and the No. 6 mines. <br />Presented below is a general discussion of the mining methods and equipment utilized in standard room and pillar <br />mining. <br />The room and pillar mining method employed by EC develops mains and submains on advance, and large areas or <br />panels are developed for pillaring. A list of the major equipment utilized in room and pillar mining is presented in <br />Table 54, Room and Pillar Equipment List. <br />Each coal seam has been engineered for extraction by developing an entry, with the height and width based upon [he <br />immediate strength characteristics of the roof, floor, and coal. The pillars are then designed to accommodate [he <br />readjusted load of the overburden strata. Certain areas are designed for full extraction of the pillars where the roof is <br />allowed to cave behind the pillared areas. <br />EC has maximized resource recovery by adopting a maximum recovery rate compatible to the anticipated stress loads <br />in accordance with prudent mining practices. <br />A continuous miner and shuttle car system is used to cut and haul the coal to the belt conveyor systems. In <br />conjunction with the standard room and pillar mining system, EC uses a pillar extraction system to optimize resource <br />recovery. During the many years of its operation, EC has employed the use of several room and pillar mining plans. <br />EC has used a three entry, four entry, and five entry system. To give a better understanding of how these entry <br />systems work, EC has included within this permit several figures to explain the function of room and pillar mining. <br />These figures are the following: <br />• Figure 48, Typical Three Entry System <br />• Figure 49, Typical Four Entry System <br />• Figure 50, Typical Five Entry System <br />• Figure 51, Typical Room and Pillar Mining Section <br />• Figure 52, Typical Partial Pillaring Plan <br />Contingent on mining conditions, the room and pillar method may follow the general patterns shown on these figures. <br />EC will use the previously mentioned major equipment in its extraction of coal, whether it is a three entry, four entry, <br />or five entry room and pillar section. This equipment is coordinated at the face to develop the number of entries <br />necessary for the specific development or mining according to several parameters determined as mining occurs. <br />These parameters include coal seam height, consistency, fault location, type of panels being driven, water conditions, <br />and overlying surface structures. <br />Room widths are generally 20 feet, but may vary depending on roof and floor conditions. Pillar size, length of rooms, <br />coal for roof support, room widths, and angles of cross cuts may vary according [o the approved MSHA plan. The <br />anticipated sizes are determined and set forth in this section. <br />Three entry systems are generally used to develop inside panels. Generally, mains are developed by five entry <br />sections and remain for the duration of the mine. Occasionally, four entry systems are used when severe roof, floor, or <br />coal conditions are encountered requiring the operator to drop one of the five entries. However, this does not preclude <br />[he use of four entries for panel development. <br />Permit Revision 04-34 2.05-5 Revised 7/2/04 <br />