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separated the Green River Basin into two parts. Its upward movement was reactivated during <br />the Tertiary and since then most of the Tertiary -age rocks have been eroded away (Young and <br />Young 1977: 57). Within the study area the Cretaceous -age sedimentary rocks including <br />sandstones and shales along with major coal beds of the Williams Fork Formation form the <br />bedrock. <br />The study unit lies within the Williams Fork Mountains, which form the divide <br />between the Yampa River Valley to the north and the Williams Fork Valley to the south. <br />Buck Peak lies to the northeast. These mountains are heavily dissected by tributary drainages <br />that flow northeast to the Yampa River and southwest to the Williams Fork River. <br />Permanent and intermittent drainages occurring near or within the project area include <br />Jeffway Gulch, Deal Gulch and Spring Gulch, which drain into the Williams Fork River to <br />the south, and Deacon Gulch, which drains into the Yampa River to the north. The <br />headwaters of many of these are fed by unnamed springs located throughout the study area. <br />Soils in the project area include Bulkley silty clay, an alluvium derived from shale <br />located on hills and alluvial fans (USDA NRCS 2004:43); Foidel loam, found on <br />mountainsides and formed from loess and colluvium derived from fine grained sandstone and <br />shale (ibid.:78); Herperus fine sandy loam, located on hills and plateaus and formed from <br />loess and in alluvium derived from sandstone and shale (ibid.:97-99); Lamphier fine sandy <br />loam, a colluvium and residuum derived from sandstone found on mountainsides (ibid.:109); <br />Lamphier-Jerry complex, found on plateaus and mountainsides, with Jerry being formed from <br />residuum derived from shale (ibid.:110); Morapos loam, located on plateaus and formed from <br />residuum derived from shale and in loess (ibid.:123, 124); Torriorthents-Rock outcrop, <br />located on the backslopes of hills and mountainsides with Torriorthents formed from <br />residuum and colluvium derived from sandstone and shale (ibid.:171); Ustorthents, frigid- <br />Borolls complex, located on footslopes and backslopes of mountainsides and both formed <br />from residuum and colluvium derived from sedimentary rocks (ibid.:177); and Winevada- <br />Spiltro complex located on plateaus and mountainsides and both formed from residuum <br />derived from sandstone (ibid.:184). <br />Elevations within the project area range from approximately 6880 to 7640 feet. The <br />dominant vegetation within the project area is comprised of Transitional Zone brush <br />including oakbrush, serviceberry, Gamble oak, and chokecherry. Aspen, dogwood, prickly <br />pear, sagebrush, yarrow, mules ears, manzanita, aster, globe mallow, snap dragons, sego lily, <br />wild pea, saw grass, thistle, Indian paintbrush, snakeweed, lupine, mint, wild rose, wetland <br />grasses, and wild sunflower are also present in some parts of the study area. Overall, ground <br />visibility was poor to moderate. This biome supports a variety of wildlife species. Mule deer, <br />elk, coyote, and black bear are locally common as are jack rabbits, cottontail rabbits, and <br />various other rodents. Mountain lion, bobcat, fox, beaver, skunk, badger, and weasel are also <br />area inhabitants. Observed bird species include the pinyon jay, raven, red -shafted flicker, <br />red-tailed hawk, golden eagle, bald eagle, and various other raptors. <br />2 <br />