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. EXHIBIT I -SOILS INFORMATION BACKGROUND Information regarding soils within the project area has been gathered using the published soil survey for the Pueblo area (Cason et al., 1979), asite-specific soils study for Rio Grand Portland Cement Corporation (Hipwell, 1998), and observations and soil profiles excavated by Greystone during a May 2001 site visit. The map included as Exhibit C is based on the Pueblo area soil survey maps. The 1998 site-specific soils study includes results of a laboratory sample analysis. , Exhibit I includes a description of the geologic setting and soil-forming environment and descriptions of the soil mapping units found at the site. The physical and chemical qualities of site soils are compared with topsoil and overburden suitability guidelines for Wyoming (Wyoming DEQ, 1994). These guidelines are generally applicable to Colorado that has no state soil suitability guidelines for mined land reclamation. The results of the soils description and laboratory analyses are compared with the May 2001 field observations. Finally, the suitability of site soils for reclamation and an assessment of the adequacy of the quantity of available soils are discussed. NATURE OF THE SOIL FORMING ENVIRONMENT . The project area lies within the Colorado Piedmont physiographic province. Site topography is chazacterized by a relatively featureless plain that dips gently to the northeast and is cut by very shallow ephemeral drainages. This plain is truncated to the west of the surface mine site by a high escarpment. Drainage from the site is to the north, reaching the St. Chazles River just east of a railroad bridge. Mine site elevations range from 5015 to 5305 feet above sea level. Thus, total surface mine site relief is 290 feet and the ground surface dips I to 3 degrees to the northeast. The low point at the surface mine site is approximately 150 feet above the 100-year flood elevation for.the St. Charles River. Site -soils have formed in weathered limestone, shale, and sandstone of the Fort Hays Limestone member of the Niobrara Formation (upper Cretaceous age). Below the clay loam, silty clay loam, and sandy clay loam soils is a caliche (hazd pan) layer. Directly below the caliche is a zone of highly weathered and broken fragments of bedrock. SOIL DESCRIPTIONS The Pueblo area soil survey indicates that three soil mapping units are found at the surface mine, plant, and fill areas. Manvel silt loam, 1-5% slopes, covers more than 75 percent of the surface mine azea and all of the plant and fill areas. -More than 20 percent of the surface mine azea is covered by the Penrose-Minnequa complex, 1-15% slopes. About two percent of the surface mine area is covered by the Penrose-Rock outcrop • complex, 25-65% slopes. Additionally, an insignificantly small area of Haverson silt loam is found at the northern edge of the surface mine azea. APPExhibitsA-T-APPQ I B°)RevB/Ianuary 17, 2002 1-1