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on the Site appears to compare favorably with the following technical standards for cover and <br />species diversity that were adopted by the Division at the Blue Flame Mine, a similar <br />underground coal mine site located approximately nine miles to the southwest of the Site. The <br />Blue Flame Mine site is similar to the Site in terms of climatic conditions, soil erodibility <br />characteristics, and post-mining land use. <br />Blue Flame Mine Cover and Diversity Technical Standards <br />Herbaceous cover: 30% <br />Species diversity: 2 cools season grasses <br />2 warm season grasses <br />2 forbs <br />2 shrubs <br />No single species shall compose more than 40% <br />or less than 3% relative cover <br />The open grassed area on the revegetated part of the Arness-McGriffin Site is surrounded by <br />undisturbed hill slopes that are covered by woody shrubs which provide areas of wildlife cover and <br />forage. No species toxic to wildlife have been found on the Site. <br />Erosion Control and Sediment Yield <br />The vegetative cover on reclaimed areas at the Arness-McGriffin Site appears to be significantly <br />preventing rill and gully formation. During the bond release inspection and recent Division <br />inspections, down-cutting from concentrated flow has been found only on a steep section of the <br />public dirt road that crosses the Arness-McGriffin Site and in gullies on the hillslope that extends <br />from the Site down to the valley bottom on the adjacent Peerless Resources Inc Coal Gulch Mine <br />site. The public road has been regraded in past years, presumably by the Colorado Division of <br />Wildlife who manages the Perins Peak State Wildlife Area to which the road provides access. <br />Sediment from the gullies on the hillslope has been deposited as a sediment fan near the middle of <br />the flat valley bottom of the adjacent Peerless Resources Inc Coal Gulch Mine site. The gullies <br />appear to have stabilized as down-cutting has reached bedrock in most places in the gullies. Gully <br />erosion occurs on a steep section of the public road on the reclaimed portal bench. <br />Using the visually estimated cover values in the Universal Soil Loss Equation, the calculated soil <br />loss rate is 2.6 tons/acre/year, calculated as: 40R X 0.30K X 3.OLs X 0.071 X O1.Op = 2.6 <br />tons/acre/year. The USLE is the product of the following five factors: rainfall-runoff (R), soil <br />erodibility (K), slope-length-steepness (LS), cover-management (C), and erosion control practice (P). <br />The calculated soil loss rate of 2.6 tons/acre/year is a moderate soil loss rate for steep-sloped <br />rangeland in southwest Colorado, and indicates the cover is adequate for erosion control. <br />Support of Post-Mining Land Use <br />The reclaimed lands have vegetative cover composed of a variety of grasses, forbs, and woody <br />6