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r <br />Geology <br />The geology of the permit area is typical Cretaceous Dakota formation with interbedded <br />sandstones and shale. The Dakota formation lies below the well known Mancos shale <br />formation. Within the formation are the Upper and Lower Dakota coal seams, <br />historically mined in the area. The Dakota formation is exposed on the surface in some <br />areas but in most areas it is covered with a thin covering of soils and topsoils. In the <br />mining permit area, the topsoil ranges from 0 to 10'. Mapping of soil for the mine shows <br />an average salvageable topsoil thickness of 2.0'. The overburden of sandstones and shale <br />above the first minable coal seam, Upper Dakota, ranges from 10 to 90' thick. The <br />Ask Upper Dakota coal seam thickness ranges from 0.75 to 2.0'. The inter-burden between <br />the Upper and Lower Dakota is typically 8-10' of predominately sandstone. The lower <br />Dakota coal seam has a thickness of 4.0-7.5'. <br />Alk <br />Equipment Move <br />-- Most of the equipment used in the mining operations is off-road equipment and cannot be <br />easily relocated to the new mine site on the County roads. Upon completion of mining in <br />the current location, the majority of the equipment will be moved overland through a <br />previously mined and reclaimed area to the new site. The 4200' route will include <br />crossing Tuttle Draw near the south end and crossing County Road AA on the north end. <br />The proposed route for the move is shown on Sheet 2 of 6, Exhibit A. The route will be <br />permitted with a 50' width and the minimum disturbance necessary to move the <br />equipment. Minor clearing and grading may be done along the route but the move will <br />not require removal and replacement of topsoil. Upon completion of the move, grading <br />will be done to eliminate rutting that may occur and the path will be seeded and mulched. <br />The creek crossing will include the temporary placement of a 30" steel pipe with <br />approximately 5' of cover over the pipe. The County road crossing will be coordinated <br />with the County Road and Bridge Department to ramp over the existing road with a <br />minimum of 3' of soil. During the road crossing, traffic will be detoured north on 2650 <br />Road to Z Road and down 2600 Road to AA Road. The move is expected to take a week, <br />including two days for the road crossing. <br />Mining Methods <br />The mining method to be employed is referred to as surface mining or open pit mining. <br />Sheet 6 of 6, Exhibit A, shows a typical section of the mining and reclamation area. The <br />operation advances through the reserve area by first removing topsoil in advance of the <br />next cut to be mined, and transporting the material around the existing pit to the area <br />being reclaimed or to a stockpile. The operation disturbs and reclaims approximately 25 <br />acres per year. The next step is drilling and shooting the overburden above the upper <br />coal seam. By a method referred to as "cast-blasting", 20-25% of the material shot lands <br />in the adjacent mined out pit. The remaining rock is moved to the previously mined area <br />using a shovel, trucks and large dozers. The rock is removed to expose the coal in a long <br />strip. A dozer is used as necessary to loosen the coal, which is loaded into highway rated <br />trucks with a front-end loader for transport to the power plant. The inter burden between <br />the coal seams is drilled and shot or ripped with a dozer and moved to the adjacent <br />backfill area. The lower seam is then mined using the dozer, loader and trucks. <br />Page 4