2024-05-17_REVISION - M1977493 (3)

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Permit M-1977-493—Climax Mine Technical Revision 37 (TR-37) 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. 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 Cryochrepts include the Hechtman, Leighcan and Scout soil mapping units. 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 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 noted. Organic matter levels were low. Potassium, zinc and iron levels were tolerable. The pH ranged within levels suitable for good grass growth and salt levels posed no problems for revegetation. Climax has continued to conduct annual topsoil, subsoil, biosolids and rock cap soil testing to determine appropriate amendments for final reclamation. Soil pH, nutrient and organic matter deficiencies are currently being ameliorated by amending waste rock cap materials with salvaged soil materials, lime products such as agricultural lime and quick lime, and composted biosolids. 1-6 Soil Handling Estimated remaining soil salvage areas by soil map unit are contained in Tables I-1, I-2 and I-3 for the McNulty and North 40 OSF, Mayflower TSF, and pit area, respectively, with a mass balance summary contained in Table I-4. The tables contain a listing of the soil map units, series and inclusions predicted to be affected by mining activities within select areas within the affected area boundary. Soils with similar physical and chemical parameters that are best suited for a vegetation type associated with a particular postmining land use (upland grass, alpine, forest or riparian) may be salvaged together and either stockpiled or direct hauled. Due to the mixing of these similar soils during the stripping and stockpiling operations, the respread soils may not exhibit exactly the same physical and chemical constituents as the Exhibit 1 I-2 March 2024