2011-10-28_PERMIT FILE - C1981012A (4)

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and Roads - West Portal and Map 21, Non Coal Waste Disposal Area). As per Division request, the Applicant plugged and abandoned the cased well in the area of the non -coal waste disposal site. In addition, the east -west drainage on the north side of the dump will be maintained rather than filled in as shown on Map 14, Sediment and Surface Water Control Plan-West Portal. Maintaining this drainage will allow flow on the north side of the dump into the eastern most evaporation pond. Other waste material such as machinery, scrap iron, equipment, which has some salvage value, is placed in the scrap storage area shown on Map 12, Surface Facilities and Roads -West Portal. The non -coal waste disposal area will be routinely compacted and covered to prevent combustion and airborne wastes. The Applicant will place a maximum of 2 feet of soil or underground development waste over the dump. The Applicant understands the area must be vegetated to meet the standards of Rule 4.15.8. In addition, operation of the dump will meet state, federal and county standards. Petroleum products which are used in the normal mining operation will be collected and recycled where possible. Where recycling of the petroleum products is not possible, they will be sold to local petroleum dealers as waste oil. The Applicant will also dispose of all hazardous materials according to all state and federal regulations. Refuse Disposal Area The refuse disposal area was permitted and construction began in 1984. Both the RDA and Development Waste Pile have been undermined as shown on Map 3, Mine Plan and Map 22 Mine Progress. No vertical or differential displacement was observed as a result of subsidence. Old Allen Mine workings range from 320 to 900 feet below the RDA. The area was partially undermined about 1963 by room and pillar methods. Extraction percentages within the area are estimated at less than 50 %. It is believed that the limited extraction has retarded subsidence and that the 35+ years that has elapsed since mining is sufficient time for any adverse effects to become evident. As a result, no adverse effects of underground mining on stability of the waste piles are anticipated. The refuse disposal area has a design capacity of approximately 12.7 million cubic yards. This should be sufficient capacity to continue operations for approximately 10 years operation. The refuse belt extends to an elevation of approximately 7,610 feet, as shown on Map 24, Refuse Area. In 2011 a 200 foot long 36 inch wide rigid conveyor was installed at the end of the existing refuse conveyor to bring the belt up to an elevation of 7,645. The conveyor was placed in an eighty foot long 10 foot diameter steel tube where it crosses over the east perimeter rip -rap ditch to eliminate the accumulation of belt dribble in the rip rap channel. Two 150 foot long radial stackers and a 500 foot long portable belt are used in series to spread the refuse over wide areas on the active bench. Refuse on the active bench is spread, placed and compacted to 90 percent of its maximum dry density to prevent spontaneous combustion and to provide the strength required for stability of the coal mine waste pile. Dry densities are determined in accordance with AASHTO T99 -74, Standard Proctor. Compaction can be performed with a variety of equipment. The compaction specification may be attained by wheel MR -97 2.05-27 Revised 09/28/11