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:EXHIBIT D-2 Page S 4 Soil Mapping Unit 7e Dark-colored soils with light_colored eubaurface horizons of the cold mountain slopes Most of this unit.is 1n naicional forests et elevations about 7,500 feet. It is all in Colgrado except for one area in Utah bordering the La Sal Mountains. Thi~lunit is extensive, comprising 22.5 percent of the bash. Precipitation is plentiful and the water yield is high. The short growing season limits crop production to hay and pasture. The landscape cons;sC:s of roiling to steep mountainous terrain with intervening canyons, valleys, and outweah fans. There are many springs and perennial streams. 'fhe vegetative cover consists of spruce-fir, ponderosa pine, aspen, oakb:ush, and some open grassland areas. About 69 percent of 'the soils in this unit have dark-colored surface layers, high in organic matter, 7 to 20 inches thick. Underlying tLia is s light-coic:ed, spray, stiosurface layer that is 4 to 16 inches thick. Textures are toderately fine i:o moderately coarse. Below the gray sub- avrface layer is a blocky subsoil that is more clnyey than the overlying layers. These horizons are neatral to slightly ncid. Gravel and stones are often present. The underlying parent material is sometimes calcareous ind is u~i;aliy at depths of 30 inches ~r more. About 18 percent of this unit has sous that Ere leas ctan 20 inches deep over parent materiels. Included with these soils are rack outcrops. Another 15 percent of the soils have dark-colated surface layers less than 6 inches thick overlying a yray.aubsurface layer and blocky subsoils. The soils are slightly acid to ncid. 7oorly drained alluvial soils compose the remaining 3 percent of the v~it. 5oii Kappinq Unit 8: There are seven small delineations of this unit. They encompass high mountain peaks and ridges at elevations above 11,000 feet. This unit is the least extensive in the basin but precipitation and water yield are high. Sediment yield is less than 0.2 acre-feat per square mile per year. The landscape is characterized by rugged mountain peaks with intervening ridges and, valleys, all above timberline. Slopes are steep to very steep. This is a windswept area of alpine meadows and rock. This unit is mainly con+posed of three components. All of the soils have dark-colored surface layers and are acid. About 50 percent of the unit is rock outcrop and talus elopes. Hbout 25 percent is shallow well- drained soils high in organic matter. Surface layers and subsoils ere ~aually rocky or stony with moderately sandy textures overlying bedrock at 20 inches or less. Anoti:er 20 percent consists of moderately deep, foamy textured, well-drained turf soils centeining stone and grovel. :Inderlying parent material is at depths of 20 to 90 inches. The remaining S percent of the Lnit consist of poorly drained peat and bog soils in low depressions and drainages.