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Exhibirl mmhos/cm. The saturation percent of 47.2 is within the suitable range of 25 to 80 percent. The texture • was determined to be clay loam and is considered suitable. Boron concentration was 0.81 ppm, well below the upper suitability limit of 5.0 ppm. The sodium absorption ratio (SAR) was 0.6, much below the upper suitability limit of 10. The selenium concentration was 0.12 ppm. This result was slightly above the upper limit of suitability (0.1 ppm) and was within the low end of the marginal range. The remaining suitability criterion, coarse fragments as a percentage of total sample volume, was not measured. A visual examination was made of soil profiles in pits excavated during the May 2001 site visit and profile photogaphs taken for the 1998 study. Based on these observations, it appears that the percentage of coarse fragments from the surface to an average depth of 30 inches is well below the upper limit of 25 percent coarse fragments for a soil to be considered "suitable." Below a depth of 30 inches, the soil appears to have greater than 25 percent coarse fragments, making it marginal or unsuitable for use as topsoil. Based on soil survey mapping and the 1998 and 2001 field examinations, it appeazs that suitable soils from the surface to a depth of 24 inches aze available for use as growth medium during reclamation. Outside the areas mapped as Manvel silt loam, soil material appears to be less suitable. However, because more than 75 percent of the site is covered by Manvel silt loam, between 12 and 24 inches of suitable plant growth medium should be available for spreading over the disturbed azea during reclamation. Appendix B includes soil descriptions from the Pueblo County Soil Survey (MRCS). CONCLUSIONS From the NRCS soil survey, there appears to be an adequate volume of suitable growth medium available for reclamation of the surface mine, plant, and fill areas. It is recommended that the surface topsoil • (approximately 0 to 6-inches) and the upper 18 to 24 inches of subsoil be separated from the lower overburden and conserved in piles for use in reclamation. Suitable reclamation seed mixes are discussed in the vegetation information section (Exhibit J) of this report. REFERENCES Hipwell, Richard. 1998. Rio Grande Portland Cement Corp. Soils Study. Spectra Environmental, Houston, Texas. Larson, Roy J., Thomas J. Wiggins, Dale L. Holden, M. Bruce McCulloch, and Rodney E. Preator. 1979. Soil Survey of Pueblo Area, Colorado, Parts of Pueblo and Custer Counties. U.S. Soil Conservation Service. Wyoming Department of Environmental Quality. 1994. Guideline No. 1, Topsoil and Overburden. Land Quality Division. 1180-Mine Permit Exhibits (Ju1.03.@)FWAL.doc l-3 July 3, 2002