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1. The face-up structures for protecting the mouths of the portal tunnels (i.e., mine entries). <br />2. The mine service buildings. <br />3. The fuel storage facilities. <br />IV.6.1 Mine Entries The "D" portal consists of atwo-tunnel system. The first of these tunnel entries <br />is divided into an upper compartment for the conveyor and a tower compartment for personnel and <br />equipment access and ventilation intake. The second tunnel is used for ventilation exhaust. The entry <br />system at the East Portal ventilation area (see Map 139) consists of two tunnels used for ventilation <br />exhaust. The two tunnels at the ventilation area were extended from underground working in the "D" <br />seam. They reach the surface at the outcrop of the "D" seam coal. <br />The two tunnels at the "D" Portal area have similar characteristics. They penetrate the ground surface <br />as a rock tunnel and descend to the coal seam at a slope of 14 to 16 degrees. They were constructed <br />by conventional means (blasting and mucking) followed by installation of steel tunnel supports with steel <br />or wood lagging. <br />A "B" portal and access slope is driven from near the bath house structure down to the B Seam. (See <br />Map 101). <br />The conveyor and equipment tunnel entry and the "B" Portal are used to transport men and materials in <br />• and out of the mine. Rubber-tired vehicles are used for transportation of both men and materials. <br />The D portal tunnel entry areas are protected by a reinforced concrete face-up structure approximately <br />20 feet high and 2 feet thick. A tunnel structure consisting of structural steel members covered with <br />corrugated steel plates extends from the concrete face-up structures into the hillside. Protection from <br />falling rock is provided by a barrier fence and bench above the entries. A similar structure is in place for <br />the "B" Portal. <br />All mine entries are inspected regularly for cracks in the concrete walls, breaks in the barrier fences and <br />excessive loose stone on the benches. The bare rock slopes are also inspected for large pieces of rock <br />which could break loose. In such cases, these pieces will be broken loose and removed. Should an <br />excessive number of small rocks become a problem, the related rock face will be covered with chain-link <br />fence held in place with rock bolts and sprayed with concrete. <br />When a set of entries is no longer required, it will be sealed in an acceptable manner (see Reclamation <br />Plan). The concrete face up walls and the steel structures will be removed. The entry area will then be <br />backfilled and regraded. <br />Mine Permit Renewal #3 (Rev. 13/99) IV-3 <br /> <br />