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1 ' bedrock at 40 inches or, in places, alluvial gravelly or loamy sand to indefinite depths. A contrasting soil that may occur in this unit is very cobbly looms. Shallow bedrock areas may occur near the foothills. The top 24 inches of soil is suitable as growth medium except in the shallow bedrock areas. Runoff on disturbed soils is moderately rapid and the hazard is moderate for water erosion. The principal vegetation type on ' the Blackhall is sagebrush with some thin stands of pinyon or juniper. The site is designated a Sandstone Foothills range ' site by the SCS. ' I.2.3 Uracca-Morval Complex, 15 to 50 Percent Slopes This complex occurs on the foothills, sideslopes, and ridges on and around the site and is common on the ridges around the lower Rito Seco Valley. This is a deep, well drained ' soil farmed in alluvium and colluvium derived from a conglomerate of igneous granitic rock. Both soil types making up this complex have a dark reddish brown cobbly loam surface layer four- to six-inches thick, underlain by a light brown cobbly sandy or sandy clay loam underlain by a sandy clay loam with visible calcium carbonate. The substratum at 50 to 60 inches is a weathered sandy clay conglomerate. Soils on upper ' slopes or ridge crest may be shallower to bedrock. The upper 18 to 24 inches is suitable as growth medium, except in areas where bedrock is very shallow. Limitations on use of this soil for reclamation are rapid runoff and moderately severe erosion hazard. The vegetation type on this soil complex is a pinyon ' juniper woodland and this is also the SCS site designation. I.2.4 Comodore-Blackhall Complex, 15 to 55 Percent Slopes This soil complex occurs on foothills, l~~wer mountain slopes, and ridges formed in colluvium and residuum from various substrates including sandstone, igneous rock, and altered or metamorphic rock. The main portion of the mine pit I-5