2011-10-28_PERMIT FILE - C1981012A (7)

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2.04.6 (2) Surface Mining No surface mining of coal is planned within the permit area or surrounding holdings at this time. 2.04.6 (3a) Underground Mining The coal to be mined at the New Elk Mine lies within the Upper Cretaceous - Tertiary Raton Formation, a heterogeneous sequence of lenticular, argillaceous sandstone, siltstone, mudstone, and coal. Lithology types are highly variable, both laterally and vertically, with correlations being best established through the occurrence of coal seams. Surface and near- surface bedrock in the mine area is limited to the Tertiary Poison Canyon Formation and the Raton Formation as shown by Map 5, Geology. The Poison Canyon Formation intermittently tops the hills in the mine vicinity. The mine plan area lies on the west flank of the Raton Basin, an asymmetric, north -south trending structural trough. In the proposed permit area, the rocks dip gently to the east - northeast at 2 to 4 degrees and averages 2.2 degrees. Easterly trending normal faults were encountered during previous mining and were successfully traversed without significant adverse effects. A complex of dikes and sills have been identified in an area just 3 miles northeast of the current New Elk Mine and within the area around the town of Weston which is east of the New Elk Mine. A thin dike was encountered in the old workings of the Allen Mine but was crossed with minimal impact to the mining operations. 2.04.6 (3a) (i) Four coals seams are of mining interest in the proposed permit area and include, from bottom to top, the Allen, Apache, Maxwell and Blue seams. Both the Allen and Apache seams attain mineable thickness throughout most of the proposed permit area, whereas the Blue and Maxwell seams are more local in extent. The thickness of the Allen Seam varies from 2 to 8 feet, with significant areas having thicknesses exceeding minimum mineable height (see Map 6A -Sheet 4). The Allen Seam averages about 5.5 feet thick in the proposed permit area. This seam was extracted in the old Allen mine and extensive workings prove its continuity and mineability. Some local channeling and slumping were encountered during mining and will likely be present in the proposed permit area. The structure and overburden of the Allen Seam is shown on Map 6A -Sheet 12 and Map 6A -Sheet 8, respectively. The Apache Seam is stratigraphically located 20 to 50 feet above the Allen Seam (see Map 6A -Sheet 15) and has a thickness ranging from 1 to 6 feet (see Map 6A -Sheet 3). The Apache seam averages about 4.5 feet within the proposed permit area. The Apache Seam has not been previously mined in the area, albeit locally when Allen Seam anomalies arose. The TR56 2.04-11 c Revised 5111