2009-10-30_PERMIT FILE - C1982056 (4)

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Twenty Mile Coal Company — West Mining District Vegetation Mapping Report The Peabody Twenty Mile Coal mine proposes to expand underground operations into the West Mining District area. The riparian bottomland corridor along Fish Creek was mapped in October of 2007 to establish a baseline vegetation community boundary to be used in future underground mining subsidence monitoring and vegetation communities were mapped on the proposed disturbance area for proposed surface facilities in September of 2008. The boundary of the Fish Creek riparian corridor was mapped by Wayne Erickson and Noel Weisenbacher of Habitat Management, Inc. Initial vegetation community mapping was completed using aerial photographs, verified in -field through site inspection and adjusted as necessary using Trimble GeoXT GPS units. The riparian complex is associated with bottomland areas along stream channels in alluvial deposits. Areas of wet meadow and emergent marsh within the riparian complex were mapped. Dominant plant species found in this complex include: Rocky Mountain alder, Wyoming big sagebrush, silver sage, smooth brome, redtop, bluegrass, inland saltgrass, spikerush, cattails and Nebraska sedge. Within the West Mining District permit boundary 188.3 acres of riparian complex were identified, with an additional 38.9 acres within the underground mining subsidence buffer zone (outside of the district boundary). There are 2.2 acres of wet meadow and 0.9 acres of emergent marsh within the riparian complex. Another 1.13 acres of wet meadow occurs adjacent to, but not contiguous with the riparian complex as shown on the map, "Fish Creek Riparian Complex." Inclusions of Wyoming big sagebrush upland were mapped when they occurred within the bottomland. The big sagebrush upland vegetation community is an upland rangeland dominated by dense patches of Wyoming big sagebrush. Some native graminoids, forbs, and shrubs occur in the shrub understory and inner -space in the shrub mosaic. Typical grasses include crested wheatgrass, several bluegrass species and mountain brome. Forbs include white yarrow, common dandelion and a variety of mustard. Shrubs include big sagebrush, silver sage, and Woods' rose. While there is a great deal of this vegetation community present in the West Mining district, only inclusions within the riparian corridor were mapped. These inclusions make up about 1.1 acres of the riparian area, 0.8 acres within the West Mining District Boundary and 0.3 acres in the subsidence buffer area. The riparian complex and associated communities are shown on "Map 1. Fish Creek Riparian Complex." The 51.5 -acre proposed surface facilities area was mapped by Wayne Erickson and Lindsey Brandt of Habitat Management, Inc in September of 2008. The proposed facilities area is comprised almost entirely of improved pasture with the exception of the southern edge. The improved pasture is comprised of crested wheatgrass, smooth brome, timothy and orchardgrass, with composition varying with aspect and degree of slope. The southern edge of this area follows a drainage made up of riparian bottomland, a sagebrush transition zone between the pasture and the riparian zone, and a few seep areas. The seeps appear to be alkaline as evidenced by surface precipitate and crusting, and are heavily impacted by cattle trampling. The northeast portion of the shaft area is intersected by the highway corridor, and a small area of sagebrush grassland and a small grove of cottonwood trees are present. The Improved Pasture portion of the area comprises 45.4 acres; the road corridor occupies 3.8 acres, and the small cottonwood stand Habitat Management, Inc. 1 April 17, 2009