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Four coal zones containing minable seams outcrop along the face of the <br />Bookcliffs in Colorado. The stratigraphically highest zone has been named the <br />"Carbonera coal zone." Two or three seams are usually present in this zone. <br />About 60 feet below the Carbonera coal zone is the Cameo coal zone. One or <br />two seams are commonly present in this zone. Where there are two coal seams, <br />the interval between them is 30 feet or less. The Cameo zone is thick, <br />laterally extensive, and the most productive coal zone in the Bookcliffs <br />field. The Lower Cameo seam immediately overlies the Rollins Sandstone. The <br />interval between the base of the Cameo coal zone and the base of the Palisade <br />coal zone, the next lower coal zone, ranges from 200 to 450 feet, being <br />greater in the east than in the west. The Sego Sandstone underlines the <br />Palisade zone and is a regional formation correlation marker. The interval <br />between the base of the Palisade coal zone and the base of the Anchor coal <br />zone, the lowest of the four, ranges from 45 to 60 feet. <br />Of the four coal seams present in the Bookcliffs coal field, only the Cameo <br />'B' and 'C' seams are recognized as being minable in the permit area. The <br />Cameo 'B' seam is presently being mined at the Roadside mine on the east side <br />of the Colorado River and at the Cameo No. 1 mine on the west side. The Cameo <br />'B' seam varies in thickness from a minimum of four (4) feet to a maximum of <br />eleven (11) feet in the permit area. The minable seam averages about six (6) <br />feet in thickness. The coal has been classified as high volatile bituminous <br />characterized by low sulfur and a moderately high ash content. <br />Further information on the geology of the permit area can be found in Sections <br />2.04.5 and 2.04.6 of Volumes I and V. <br />The analyses of the roof, floor, coal and refuse materials in Appendix 0 of <br />Volume V indicate that the materials are generally high in iron (Fe), and have <br />a high pH and sodium absorption ratio (SAR). The high iron level should not <br />pose a significant problem because iron is relatively insoluble at the high pH <br />values characteristically found in the materials. In addition, the sodic <br />nature of the materials is not a significant problem. The sodium levels are <br />similar to those found in the soils of the area and much lower than those <br />found in the exposed strata, such as Mancos shale, which outcrops in the <br />general vicinity of the mine. The high sodium content would not affect the <br />plant growth characteristics of the materials, since these sodium quantities <br />are not toxic to plants, but rather destroy the structure of soils, <br />particularly in soils of predominantly clay texture. The result of this <br />breakdown is a decrease in the infiltration rate, thus a decrease in water <br />available for plant growth. However, the refuse material, which is the only <br />waste material which may be subject to revegetation activities, is coarse <br />textured (70+% sand size), thus there should be no problems. <br />The proposed operation is in compliance with the requirements of this section. <br />_11_ <br />