1999-04-26_PERMIT FILE - M1999051 (2)

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EXHIBIT I SOILS INFORMATION The following soils information is submitted as Exhibit I for the Colorado Division of Minerals and Geology Regular (112) Operation Reclamation Permit Application for the AmerAlia Rock School Lease Project. The soils on the Rock School Lease Project area were mapped by the Soil Conservation Service (SCS; now the National Resource Conservation Service) in an Order III soil survey of Rio Blanco County. An Order III survey mainly delineates soil associations, complexes, and consociations with a minimum size map unit of about 6 acres. Complete detailed maps and mapping unit descriptions (from which much of this information was taken) exist in the published survey by the SCS, 1982. SCS Map Sheet No. 29 — (U.S. Geological Survey Wolf Ridge Quadrangle) contains the Project area and soil mapping units occurring on the Rock School Lease are listed in Table I-1, along with the respective acreages. The physical characteristics of the soils are listed in Table I-2. The soil mapping unit delineations are shown on Figure I-1. The soil resource within the project area is extremely variable, depending on the soil parent materials, vegetation, slope, aspect, and time in place. The soils within the area are cold, with a mean annual soil temperature of less than 470F and are dry for a large portion of the time when soil temperatures are warm enough for plant growth. The soils throughout the project area are generally alkaline or saline because the precipitation is insufficient to leach the salts from the soils. The pH values range from near neutral to moderately alkaline (U.S. Bureau of Land Management, 1986), which is typical for areas with low annual precipitation— less than 16 inches per year. The soil mapping units are described below. 1-1 SOIL MAPPING UNIT 36—GLENDIVE FINE SANDY LOAM This soil type is deep (60 inches or more), well drained, and is found along drainage ways on alluvial valley floors. The potential plant community on this soil is mainly basin wildrye, western wheatgrass, Indian ricegrass, and big sagebrush. Typically, the surface layer is pale brown sandy loam 6 inches thick. The underlying material to a depth of 60 inches or more is very pale brown, stratified fine sandy loam that has thin lenses of loamy fine sand to sandy clay loam. The soil is calcareous throughout. Permeability of this Glendive soil is moderately rapid. Available water capacity is moderate. Effective rooting depth is 60 inches or more. Runoff is slow, and hazard of water erosion is slight. G:\LMM78545.002\Reclamation\Reciamexh.DOC I-1