Figure 6.— Waste coal clumped below the entry of the abandoned Reminger coal mine in Utah. A single 8- to 10-foot coal- 

 bed was mined and transported to bins through wooden chutes. The mine ceased production in the late 1940's. This scene 

 is typical of the entrances of old abandoned underground coal mines. Sparse clumps of ricegrass grow on the base of the 

 slack coal. The woody debris consists mainly of juniper trees that were killed by landslides. These steep slopes are not con- 

 ducive to revegetation. The rockfall has partly covered the old access road in the foreground. October 1978. 



summer months, usually during short, high- 

 intensity storms. Mean annual temperatures 

 (degrees Fahrenheit) generally are in the 40's, ex- 

 tending into the 50's in New Mexico and Arizona. 

 The range in latitude and elevation is reflected in 

 changes in evaporation rates (fig. 16) which gen- 

 erally increase from north to south and, more 

 specifically, in the length of the growing season, 

 which can be as short as 60 days (in Colorado) 

 and as long as 145 days (in Arizona). 



burden of the Fort Union Formation in North 

 Dakota and Montana. Soils vary from clayey to 

 sandy depending on the underlying rock type. 

 They are usually shallow and contain thin "top- 

 soil" layers and limited organic matter. Subsoils 

 are typically finer textured than the surface soils 

 and often have accumulations of calcium car- 

 bonate or calcium sulfate (gypsum). Soils having 

 high sodium content may be present in depres- 

 sions and where soils have formed from shales. 

 Moderate salinity in soils is common. 



GEOLOGY AND SOILS 



Most of the western coalbeds are thick and 

 relatively flat, have a low sulfur and ash content, 

 and are of similar geologic age— Cretaceous 

 through early Tertiary. They are usually overlain 

 by shales and sandstones, some of which have 

 high salinity and (or) sodium content. Sodic 

 swelling clays commonly characterize the over- 



VEGETATION 



The natural vegetation in the western coal 

 region is typically western zonal, responding to 

 precipitation, latitude, altitude, and aspect. 

 Overall, plant species and density are closely 

 related to soil characteristics and climate. The 

 lands to be mined are grassland, shrubland, or 



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