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The Leadville Mill • Deposits were originally deposited as sulfides, and probably as a mixture, in varying proportions, of galena, and pyrite; • Deposits were deposited from aqueous solutions; • The process of deposition was a metasomatic interchanging between the materials brought in by the solutions and those forming the country rocks, consequently they do not fill pre- existing cavities; • Ore currents from which they were deposited did not come directly from below, but were more probably descending currents; and • Currents probably derived the material of which the ore deposits are formed mainly from the porphyry bodies which occur at horizons above the Blue Limestone. The geology is described in greater detail in USGS Professional Paper 148 by Emmons, Irving & Laughlin, 1927. 3.4 SOILS (SEC 6.3.2(A)) The mill site soils, as described by USDA - Salida, Colorado District office, were formed on glacial outwash sedimentary rock with slopes ranging from 3% to 35 %. The soils have stony characteristics which predominate throughout the soils profile. Soil is generally less than 6in thick. Areas that have been historically cleared (roads, benches) show very good re- growth without fertilizer or other amendments. Soils are described in greater detail in Section 5. 3.5 VEGETATION (SEC 6.3.2(B)) 3.6 WILDLIFE (SEC 6.3.2(D)) M 1990 -057 EXHIBIT B — SITE DESCRIPTION Page 3 -4 Coniferous trees cover the site, except the area where the Leadville Mill building, access roads and TSF are located. Lodgepole Pine is the predominant tree species. Approximately 1.7ac of trees and underlying vegetation were removed during construction of the new TSF. UMC contacted the Colorado Department of Wildlife (CDOW) to determine an effective mitigation plan to prevent impacts from milling operations on local wildlife which includes deer and elk. CDOW recommended modification to a 4- strand Version 1.0 April 2013