2009-02-10_PERMIT FILE - C1981022 (5)

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Saner - 2.04.7 well-drained materials, however, sodium is rapidly leached through the soil profile and does not limit • plant growth. Weathering and leaching of the spoil material will result in increased calcium and magnesium concentrations and reduced SAR with time. This is supported by the high acid-base potentials (discussed above) which indicate the presence of CaCO3. In addition, provisions for effective control of surface drainage and infiltration in the waste pile design (i.e. underdrains and diversion channels) will effectively provide for free drainage which will prevent any significant accumulations of sodium in the waste pile material profile. No problems are, therefore, anticipated with respect to sodium concentrations in the coal mining waste materials. Texture (Tex) - Most of the materials are classified as sandy loamy, sandy clay loamy or loamy sands. No problems are, therefore, anticipated with respect to soil texture. In summary, based on analysis results, potential coal mining waste materials are expected to have neutral to moderately alkaline pH with little or no potential for acid-generation; moderate to coarse texture with limited potential for swelling or drainage problems; little or no potential for mobilization of soluble metals; and minor potential, based on texture and other factors, for development of saline conditions. Coal Seams - Five economically significant coal horizons have been identified and developed in the mine permit and adjacent areas. Two of these horizons, containing the D and E coal seams, occur in the Paonia Member of the Mesa Verde Formation, while the remaining A, B, and C coal horizons occur in the Bowie Member of the Mesa Vence Formation. The following sections describe the economically significant coal units in descending order, designated by both seam designation and local designations based on the primary mine on each seam E Horizon (Hawks Nest) - The E coal horizon occurs approximately 150 feet above the base of the Paonia Member and consists of two delineated coal seams. The E-1 coal seam is approximately 6 feet thick and is relatively continuous over the thine permit area. The E-2 coal seam is relatively continuous but reaches a mineable thickness of approximately 7 feet only in the Somerset - Hawks Nest Creek area. The E coal seam has been mined at the Hawks Nest Mine by Western Slope Carbon. Estimated coal quality parameters are; Percent ash (E-1 - 4.3, E-2 - 15.1 (includes un- sampled partings at 100%)); Percent volatile matter on a moisture/ash free basis (E-1 - 39.7, E-2 - 41.9); and Percent fixed carbon on a moisture/ash free basis (E-1 - 60.3, E-2 - 58.1). D Horizon (Oliver) - The D coal horizon occurs immediately above the massive sandstone which caps the Bowie Member and consists of four delineated coal seams, the D-lA, D-1, D-2 and a3 seams. The D horizon lies approximately 200 feet above the C seam and is laterally continuous. While the D Coal Seams may be relatively thick in certain areas, they are generally not persistent over the mine permit area, with the D-1A and D-1 seams generally being un-minable due to variations in thickness and continuity. The D-2 coal seam is approximately 10.4 feet thick and the D-3 coal seam reaches an average mineable thickness of approximately 8.8 feet. The D Coal Seam has been mined at the Oliver Mine and OlvII is proposing future D seam operations for the Elk Creek Mine. Exploration drilling did not encounter any igneous intrusives in the D horizon but drilling results did indicate that the lowermost D- IA seam had been metamorphosed in-place to natural coke. Estimated coal quality parameters are; Percent ash (D-2 - 5.6, D-3 - 11.2 (includes un-sampled partings at 100%)); Percent volatile matter on a moisture/ash free basis (D-2 - 40.6, D-3 - 42.3); and Percent fixed carbon on a moisture/ash free basis (D-2 - 59.4, D-3 - 57.7). JC Horizon (Bear) - The C coal horizon occurs approximately 70 to 200 feet above the Rollins Sandstone Member and consists of a single delineated coal seam The C coal seam ranges from approximately 1 to 13 feet in thickness, with an average mineable thickness of approximately 7.8 feet. In the Terror Creek area, the C coal seam is cut by igneous intrusive sills which have replaced much of the coal and metamorphosed the remainder to natural coke. The C coal seam has been mined at the Bear Mute, across the North Fork of the Gunnison River by Bear Coal Company. Estimated coal quality parameters are; Percent ash (C - 7.8 (includes un-sampled partings at 100%)); Percent volatile PR04 2.04-17 Revised August 2000