2011-03-14_REVISION - M1977493 (63)

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Permit Amendment (AM-06) - Climax Mine CM0000128 a subsoil argillic horizon. The typical Great Group is the Cryoboralfs, which are cold, forested soils on mountain slopes in the Climax area and are included the Leadville map unit (Appendix I-A). These soils vary in depth, but often there is a shallow depth to lithic contact. If the soil is intact on a surface-disturbed site, it naturally is suitable for reclamation purposes; but shallow depths of suitable horizons may result in low soil salvage volumes for subsequent use or stockpiling. The unaffected Leadville map unit has a typic soil profile with an O, A and E-Horizon that occurs between 0 and 22 inches in depth and a B- Horizon between 22 and 60 inches (Appendix I-A). Inceptisols are found both below and above timberline on steep and/or exposed landscapes and have limited soil development (immature). On steep slopes, weathering of the solum normally provides for a steady state relative to geologic erosion. However, over time soil development may eventually become directed toward various soil types including Alfisols. These more developed soils can provide an anchor for trees, woody plants and herbaceous species below timberline. Above timberline, the soils are vegetated with cushion plants, grasses and other herbaceous species, and represent such Great Groups as Cryumbrepts and Cryochrepts (cold alpine soil). The Cryumbrepts include the Moran and Teewinot soil mapping units (Appendix I-A). The Moran soil profile has O and A-Horizons that occur between 0 and 25 inches in depth and a B-Horizon that occurs between 25 and 60 inches from the surface. The Teewinot soil is shallow with an A-horizon that occurs between 0 and 7 inches in the profile and the B- horizon that occurs between 7 and 16 inches over rock. The Cryochrepts include the Hechtman, Leighcan and Scout soil mapping units. The Hechtman soil profile is shallow and has O, A and E-Horizons that occurs between 0 and 7 inches in the profile and the B-Horizon that occurs between 7 and 16 inches over rock. The Leighcan soil map unit has O, A and E-Horizons that occur between 0 and 14 inches in the profile and the B-Horizon that occurs between 14 and 52 inches. The Scout map unit is deeper with O, A and E-Horizons that occur between 0 and 32 inches in the profile and the B-Horizon between 32 and 74 inches. These soils are suitable for reclamation purposes in the Climax area. However, topographic position and slope may limit their salvage. Entisols are also found below and above timberline, and include soils recently exposed to the weathering process. Weathering processes include, mass wasting or erosion areas in which surficial materials are removed more quickly than soil development can occur. These soils are shallow, sandy and gravelly, and are able to support limited trees and certain herbaceous species. A typical Great Group in the alpine, the Cryorthents, include the rubble and rock outcrop lands that have only a few forbs, (such as cushion plants) and are shallow. (Appendix I-A). The soils are not suitable for reclamation purposes due to their location on steep slopes and little if any salvageable soils over rock. Mollisols have developed on the well-drained meadow areas dominated by grasses, sedges and forbs and include the Eyre and Handran map units (Appendix I-A). Thick root systems and accumulations of organic matter provide a dark, stable, base-rich surface soil. The Eyre soil mapping unit has an O and A- Horizons that occur between 0 and 13 inches in depth and a B-Horizon that occurs between 13 and 18 inches from the surface over rock. The Handran soil mapping unit has an A-Horizon that occurs between 0 and 10 inches in depth and a B-Horizon that occurs between 10 and 60 inches from the surface. The Great Groups, Cryaquolls, Cryoborolls and Haploborolls, develop both above and below timberline, and provide for a fair to good vegetation cover. The soils are suitable for reclamation purposes, but their distribution is very limited. Wetland soils and plant communities at Climax are primarily found along the Arkansas River, Tenmile Creek, and Eagle River drainages outside of the affected area mining boundary. Additional small isolated wetlands exist in various areas in the alpine and subalpine zones within the affected area boundary, but they are limited in extent. Disturbance to potential jurisdictional wetlands on the property will be addressed with regional Army Corps of Engineers (ACOE) representatives as well as DRMS as necessary. Delineation, permitting, and mitigation activities associated with disturbance to jurisdictional wetlands will be coordinated with the ACOE as appropriate. 1-5 Soil Fertility In 1976, Climax conducted a very limited soil and subsoil survey of disturbed sites over its property (31 sample sites) for purposes of fertility determination. Soil chemical analysis was performed by the Colorado State University Soil Testing Laboratory. Overall deficiencies in phosphorus and nitrogen were 0 Exhibit 1 I-2 May 2010