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12 Deep well drained soils with moderate to high available water capacities overlie • the fans and associated landforms of the project area. Alluvium and landslide materials from mixed rock sources are the dominant parent materials. Slopes range from nearly level to 40 percent with lesser slopes predomination. Soil textures range from loamy to stony loams for surface soils and from clays to extremely cobbly loamy sands for subsurface soil horizons. The mass movement potential is rated as low to medium. Rock outcrops occur across the project area and are expressed as bare rock exposures of canyon walls, escarpments, and very steep upland side slopes. Little in the way of soil is included in these map units. Vegetation The following is obtained from the Final Environmental Impact Statement, Iron Point Exploration License, Iron Point Coal Lease Tract, Elk Creek Coal Lease Tract, Delta and Gunnison Counties, Colorado, February 2000, formulated by the USDA-Forest Service, USDI-Bureau of Land Management and USDI-Office of Surface Mining Reclamation & Enforcement. The Oak Vegetation community is essentially ubiquitous across the project are occurring on ridge slopes, along ephemeral drainages, and over level to moderately rolling mountain meadows. Near pure stands of Gamble oak . (Quercus gambelir~ dominate drier ridge slopes. Where the community occurs in larger meadow and along drainages, it is more of a mixed shrub community composed of a wide variety of shrub species. This is a reflection of more mesic site conditions and wetter soil moisture regimes. The dominant shrub species is Gambel oak. Other shrubs which can be co- or sub-dominant depending upon growing conditions inclue snowberry (Symphoricarpos oreophilus or S. rotundifolis) and serviceberry (Amelanchieralnifolia). Herbaceous species such as lupine (Lupinus argenteus), white-flowered peavine (Lathyrus leucanthus), and various upland sedge (Carex) species are common in the understory (Johnson, 1997). Chokecherry (Prunus virginiana) is also a common community component while small, sub-dominant aspen (Populus tremuloides), stands may become established in wetter areas where this community borders the aspen community. Occurring across the project area over a variety of elevations and aspects is the Aspen Vegetation Type. This type inhabits less steep slopes overall than the other tree-dominated vegetation types on site, though its presence on somewhat steeper slopes under the proper soil conditions is not uncommon. It intergrades with most of the other vegetation types on site, excepting the Pinyon/Juniper, and characteristically has a more open, highly productive understory. The dominant tree species is aspen. Common understory species include Woods rose (Rosa woodsi~), mountain brome (Bromus marginatus), elk sedge (Carex geyen),white- flowered peavine, Fendler meadow-rue (Thalictrum fenlen), and American vetch (Vicia americana) (Johnston, 1997). Wetter expressions of this type, in • depressions or adjacent to seeps and springs, often form transition wetland vegetation communities.