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Vegetation Information <br />Threatened and Endangered Plant Species <br />The federal list of threatened and endangered (T&E) plant species for Colorado includes thirteen species <br />of which six are endangered and seven are threatened. Three species of concern are also listed. Of these <br />only one, the Knowlton cactus (Pediocactus knowltonii; endangered), is known to occur in, and is listed <br />for, La Plata County. This cactus inhabits pinyon juniper woodlands with mixed sagebrush. This habitat <br />is not present within the May Day Idaho Mine Complex permit boundary. Therefore no T&E plant spe- <br />cies are of concern for this project. <br />6.4.10(1)(b) Relationship of Vegetation Type to Soil Type <br />Soil type is reported by USGS as ten soil mapping units with a single unit, the Nordicol stony loam, com- <br />prising the majority of the permit area (Exhibit I — Soils Information). This soil unit is formed on sand- <br />stones of the Morrison Formation with slopes approximately 30-35° with weathered sandstone <br />predominate throughout the profile and topsoil generally less than 6" mixed with weathered sandstone <br />gravels and cobbles. The second significant soil unit is the floodplain of the La Plata River where the <br />Riverwash soil unit is formed from sandy and/or cobbly or gravelly alluvium. <br />As detailed above, the dominant vegetation is a mixed coniferous and deciduous forest with Douglas fir <br />and quaking aspen as the dominant tree species. The vegetation within the floodplain is predominantly <br />narrowleaf cottonwood with willow tree/shrub and blue spruce. Five vegetation types were mapped. <br />A comparison of soil types to vegetation types (Figure J-1) does not reveal any correlation between spe- <br />cific soil type and the vegetation type growing within it. <br />6.4.10(1)(c) Potential for Reclamation to Recreational Land Use <br />Reclamation of the affected lands will be to recreational use. For this land use, the disturbed areas will be <br />graded, seeded, and planted to match the surrounding natural topography and vegetation composition as <br />much as practical. Exhibit E - Reclamation Plan details methods of reclamation and performance stand- <br />ards for post -mine revegetation. Since future land use is not range or agriculture, an annual production or <br />carrying capacity determination is not relevant. <br />6.4.10(2) Relationship of Vegetation Type to Topography <br />Exhibit C Figure C-5 provides a map of existing vegetation within the permit area and includes the exist- <br />ing topography. This section relates vegetation type to three aspects of topography: elevation, slope, and <br />orientation. The mosaic pattern of vegetation types within the May Day Idaho Mine Complex does not <br />seem related to elevation change other than within the La Plata River riparian zone. The forested riparian <br />vegetation type is only present at the lowest elevation. All other vegetation types are present in relatively <br />equal proportions at all elevation levels with no significant change. However, the riparian vegetation type <br />may be related more to slope than elevation. <br />Vegetation type is significantly related to topographic slope mainly within the riparian zone. Other than <br />the riparian zone, the slope within the permit area is consistently between 30 to 35 degrees. Within the <br />riparian zone, the slope is relatively flat (less than 5 degrees) allowing soil moisture retention and devel- <br />Sunrise Mining, LLC <br />112(d) Permit <br />Revised July 8, 2011 <br />Exhibit J — Rule 6.4.10 <br />Page 4 of 5 <br />