Laserfiche WebLink
• <br />Mountain Coal Company Exhibit 27 <br />West Elk Mine Characteristics of West Elk Mine Soil Mapping Units <br />In their native state the soils of this unit are moderately susceptible to water erosion, <br />particularly where the natural vegetation has been destroyed or depleted. but they are not <br />very susceptible to wind erosion. If cleared or disturbed they are very susceptible to <br />water erosion and moderately susceptible to wind erosion. <br />• <br />Chemical Pro~rties and Na[ttral Fertility -These soils are moderately weathered and <br />mature. with distinct genetic horizonation including horizons of silicate clay accumulation <br />and conststen[ horizons of secondary carbonate. The cation exchange complex (ability <br />of some pans of the soil to hold and exchange cations) of the A and B'_t horizons is base <br />saturated with calcium predominating the cations. Under such conditions there is no <br />shortage of essential bases necessary for plant growth, and there is also no excess <br />calcium and magnesium carbonate to depress the availability of other plant nutrients. In <br />the C horizon there is some free carbonate (normally less than IS percent) and some <br />depression of phosphorus may be expected. There is a negligible effect on plants <br />growing on these soils as carbonates are below the root zone. A problem could arise if <br />this highly calcareous material was exposed to the surface of new seedbeds as nutrient <br />availability (especially phosphorus) could become depressed. Mixing of this material <br />with the noncalcareous surface horizon would dilute deleterious accumulations of <br />calcareous material. <br />No evidence of detrimental amounts of sodium or other soluble salt accumulation has <br />been observed for these soils. It is not unusual, however, to find sufficient sodium <br />accumulation in strongly developed horizons of secondary carbonate to affect some <br />plants. Such an accumulation is spotty. <br />Natural soil fertility is average for the area, highest in surface horizons and decreasing <br />with depth of organic matter accumulation. Any practice that destroys the upper soil <br />horizon will result in lower levels of organic matter and coherently lower levels of <br />nitrogen will be available. A fertilization program including nitrogen and phosphorus <br />would insure seedling growth and vigor in areas to be reclaimed. <br />Mapping Unit Number X38 -Moderately deep (20 to 40 inches to bedrock) and deep <br />(more than 40 inches to bedrock), well drained, medium to moderately fine textured (l8 <br />to 35 percent clay), forested soils having mature soil horizon development including light <br />colored surface horizons (thin Al and alluvial A2 horizons) and horizons of silicate clay <br />accumulation (B2t horizons) occurring in parts of the mine area where the mean summer <br />soil temperature (June. July, and August mean temperature measured at '0 inches) is <br />colder than 59°F. <br />• <br />Classification of Major Components -The components listed below comprise the major <br />part of the mapping unit: <br />Exhibit 27-30 <br />