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Mountain Coal Company Exhibit ~7 <br />• West Elk Mine Characteristics of West Elk Mine Soil Ivtapping Units <br />Iytorpholo~ical Croup 3 <br />Soils in morphological group 3 are weakly developed and well drained, have dark surface <br />horizons (A horizons). and occur in the somewhat more moist intermediate elevations <br />(6,800 - 7,000 feeq. This group includes mapping units 6, 26, and 27. <br />The soils of this group occur on valley sideslopes, alluvial drain bottoms, river terraces, <br />and on crests and shoulders of ridges and hills below 7.800 feet throughout much of the <br />mine area. Landscape positions below 6,800 feet that accumulate runoff waters, or <br />receive overtlow may develop dark surface horizons due to leaching of organic materials. <br />The soils of group 3 have only slightly greater degrees of development than do those of <br />group 1, and represent the least well-developed of the well-drained soils at intermediate <br />elevations (6,800 - 7,000 feet). Normally they have friable, granular, noncalcareous, <br />neutral to mildly alkaline surface horizons (A horizons) eight to 30 inches thick that are <br />grayish brown to dark brown or black when moist. Subsurface horizons are massive and <br />usually noncalcareous for at least 40 inches with lighter colors and usually brighter <br />chroma. Like the soils of group I, subsurface horizons may occasionally have weak to <br />moderate prismatic or blocky structure. <br />• Morohol~ical Group 4 <br />Soils in morphological group 4 are weakly developed and poorly drained, have dark <br />surface horizons (A horizons), and occur at intermediate elevations (6,800 - 7,800 feet). <br />This group includes mapping unit 20. <br />Although this is a very minor group, it is unique in character. It occurs in mappable <br />acreage only on the floodplain of the Dry Fork of Minnesota Creek where it has <br />developed as a result of poor soil drainage caused by beaver activity. Normally these <br />soils have thick, dark colored, highly organic, granular surface horizons (A horizons) <br />that are mottled with hydrated or deoxidized organic and mineral matter in their lower <br />part. At depths of 15 to 50 inches these grade to mottled and sometimes gleyed parent <br />materials. Water tables are within two feet of the around surface most of the year; <br />however, it is a moving table and apparently carries sufficient oxygen to prevent intense <br />gleying in a subsoil horizon. <br />Morphol~ical Group 5 <br />Soils in morphological group 5 are mature, have dark surface horizons (A horizons). and <br />occur at intermediate elevations (6,800 - 7,800 feet). This group includes mapping units <br />. 30, 31. and 33. <br />Exhibit '_7-35 <br />