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Mountain Coal Company Exhibit 27 <br />S West Elk Mine Characteristics of West Elk Mine Soil Mapping Units <br />B. Vertic Cryoboroll (.Chernozem). <br />1. Fine, montmorillonitic family. <br />(Kissick Series) <br />?. Very fine, montmorillonitic family. <br />(Castle Series) <br />Extent and Iyta~or areas of Occurrence - This mapping unit has a small total acreage <br />in the mine area and occurs on the southern extensions of Lion Mesa (Sections 4. 5, and <br />9; T14S, R90W). <br />Characteristic Toooeraohv - Mapping unit number X32 occurs on the gently to <br />moderately sloping tops of mesa-like landforms and intertluvial divides where the fine <br />and very fine textured sedimentary bedrocks lie moderately close to the surface. <br />Physical Properties - The soils of this unit are very fine textured and hale very wide <br />shrinWswell ratios. These two properties outweigh most of their other physical <br />properties in determining the ability to be used for most purposes. These soils are <br />subject to dense packing if traversed by heavy machinery when moist and are easily <br />• puddled to a dense impermeable mass if manipulated when wet. If disturbed when dry <br />they are extremely hard to move and tend to form large extremely hard clods that are <br />very difficult to work into good seedbeds. They can be handled over only a very narrow <br />range of soil moisture without loss of good physical properties. <br />Tonal extensibility of a 40-inch section is estimated to range from about 3.2 to 8.0 <br />inches. Under normal conditions grumasolic types of genesis (vertical soil movement <br />due to pressures created by expansion of heavy clays against crack ftllings) are not <br />pronounced; however, this is only because of the infrequency of wetting and drying. The <br />potential for such movement exists. <br />Because of their large shrink/swell ratios and their extremely fine textures. the soils of <br />this group are considered poor materials for seedbeds. <br />No evidence of mass movement is seen in these soils but their potential for such <br />movement is great. The present lack of evidence of movement is probably due to the <br />low water intake characteristic of the unit. Any practice involving the addition of large <br />amounts of water to aeas of mapping unit number X32 will enhance this potential for <br />mass movement. <br />Chemical Properties and Natural Fertility -The soils of mapping unit number X32 have <br />for the most part the same chemical properties and natural fertility as the soils of <br />. mapping unit numbers X31 and 31, with the exception of heavy, dense, expanding, and <br />contracting materials which have an effect on plan[ nutrient availability. Laboratory <br />analysis may vary, however. <br />Exhibit 27-28 <br />