2013-04-05_GENERAL DOCUMENTS - C1981019

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4.10 Vegetation Baseline vegetation information is found in Section 2.04.10 Map 4 and Exhibit 10 of the PAP original volumes. Vegetation information associated with the PR -02 Lower Wilson and South Taylor expansion areas can be found in Section 2.04. 10 of Volume 12, Exhibit 10 of Volume 13, and Maps 3, 4A, and 4B of Volume 14. Six vegetation communities and a small amount of cropland exist within the Mine permit boundary. The major communities are sagebrush and mountain shrub. Communities of lesser extent include a juniper community in the vicinity of Streeter Mountain; aspen groves in the upper reaches of Streeter, Taylor and Wilson Creeks; a limited riparian community along Good Spring, West Fork Good Spring, Wilson, and Taylor Creeks; and a small western wheatgrass community in the southern portion of the permit area. The sagebrush community occurs throughout the permit area on all elevations, slopes and soils. The community has developed wherever soil moisture retention and soil depth have become limiting to other vegetation communities. Big sagebrush (Artemisia tridentata) and snowberry (Symphoricarpos oreophilus) dominate the overstory. Dominant grasses are western wheatgrass (Agropyron smithii), mountain brome (Bromus mar inatus) and green needlegrass (Stipa viridula). Major forbs include lupine (Lu inus caudatus), wild onion (Allium sVp.), yarrow (Achillea lanulosa), and arrowleaf balsam root (Balsamorrhiza sa itg tata). The mountain shrub community is typically found on areas of higher soil moisture and deeper soils throughout the permit area. Serviceberry (Amelanchier alnifolia) and Gambel's oak ( uercus gambelii) are the dominant overstory species in the community, with fairly dense stands of chokecherry (Prunus vir ing iana) occurring on north slopes and along drainages. The most abundant grasses are Kentucky bluegrass (Poa pratensis), western wheatgrass and needle and thread (Stipa comata). Forbs include lupine, yarrow, bedstraw (Galium R.) and American vetch (Vicia americana). The aspen communities occur primarily on northwest facing slopes at elevations above 7,400 feet, in the South Taylor Pit area of the mine. Large continuous stands of aspen occurred along the upper portions of the West Fork of the Good Spring Creek in Sections 6, 31 and 32 and on the slopes leading to the East Fork of Wilson Creek in Sections 19 and 20. Aspen accounted for 13.6 percent of the vegetation in the Danforth Hills study area. In the South Taylor Pit disturbance area, aspen communities account for approximately 15 percent of the disturbed area. These aspen communities are concentrated in 10 individual communities ranging in size from approximately one acre to 122 acres. The individual communities are shown on Map 4A, Vegetation — South Taylor Mining Area. More information regarding the aspen communities can be found in Volume 12, Section 2.04. 10 and in Exhibit 10, Item 5. Proposed Decision and Findings of Compliance January 2012 Permit Renewal 06 Page 117