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• EXHIBIT I -SOILS INFORMATION <br />BACKGROUND <br />Information regarding soils within the project area has been gathered using the published soil survey for <br />the Pueblo azea (Cason et al., 1979), asite-specific soils study for Rio Grand Portland Cement <br />Corporation (Hipwell, 1998), and observations and soil profiles excavated by Greystone during a May <br />2001 site visit. The map included as Exhibit C is based on the Pueblo azea soil survey maps. The 1998 <br />site-specific soils study includes results of a laboratory sample analysis. <br />Exhibit I includes a description of the geologic setting and soil-forming environment and descriptions of <br />the soil mapping units found at the site. The physical and chemical qualities of site soils aze compared <br />with topsoil and overburden suitability guidelines for Wyoming (Wyoming DEQ, 1994) contained in <br />Appendix B. These guidelines are generally applicable to Colorado that has no state soil suitability <br />guidelines for mined land reclamation. The results of the soils description and laboratory analyses are <br />compared with the May 2001 £eld observations. Finally, the suitability of site soils for reclamation and <br />an assessment of the adequacy of the quantity of available soils are discussed. <br />NATURE OF THE SOIL FORMING ENVIRONMENT <br />The project area lies within the Colorado Piedmont physiographic province. Site topography is <br />characterized by a relatively featureless plain that dips gently to the northeast and is cut by very shallow <br />ephemeral drainages. This plain is truncated to the west of the surface mine site by a high escarpment. <br />• Drainage from the site is to the north, reaching the St. Charles River just east of a railroad bridge. Mine <br />site elevations range from 5015 to 5305 feet above sea level. Thus, total surface mine site relief is 290 <br />feet and the ground surface dips 1 to 3 degrees to the northeast. The low point at the surface mine site is <br />approximately 150 feet above the 100-year flood elevation for the St. Charles River. <br />Site soils have formed in weathered limestone, shale, and sandstone of the Fort Hays Limestone member <br />of the Niobrara Formation (upper Cretaceous age). Below the clay loam, silty clay loam, and sandy clay <br />loam soils is a caliche (hard pan) layer Directly below the caliche is a zone of highly weathered and <br />broken fragments of bedrock. <br />SOIL DESCRIPTIONS <br />The Pueblo area soil survey indicates that three soil mapping units aze found at the surface mine, plant, <br />and fill areas. Manvel silt loam, 1-5% slopes, covers more than 75 percent of the surface mine area and all <br />of the plant and fill areas. More than 20 percent of the surface mine area is covered by the Penrose- <br />Minnequa complex, 1-1 S% slopes. About two percent of the surface mine area is covered by the Penrose- <br />Rock outcrop complex, 25-65% slopes. Additionally, an insignificantly small area of Haverson silt loam <br />is found at the northern edge of the surface mine area. <br />Manvel silt loam, 1-5% slopes <br />This is a deep, well-drained soil found on alluvial fans and formed in silty colluvial/alluvial material <br />derived from limestone. Permeability is moderately slow, and the available water capacity is high. Runoff <br />is moderate and the shrink-swell potential is low. This soil has moderate water and wind erosion hazards. <br />• The native vegetation is mainly plains grasses. <br />II80-Mine Permi[Exhibits (Ju1.03.02)FINAL.dac I-1 <br />July 3, 2002 <br />