2010-12-17_REVISION - C1981019 (161)

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3.0 RESULTS 3.1 Existing Field Conditions at the Time of Survey Field conditions at the time of site evaluations in 2005 (August) were ideal for the evaluation of all three variables (vegetation, hydrology and soils). Floral growth in most areas was mature, highly productive, readily identifiable, and had not been overly grazed by domestic livestock or wildlife. Given the streamside nature of the majority of wetlands, hydrology (typically soil saturation) was also ideal for observation. In addition to experiencing ideal field conditions during August, the new CIR aerial imagery that was exposed during late September, 2005 while wetland vegetation was still actively growing, but upland vegetation was senescing, was ideal for mapping in this manner. In fact, the accuracy of wetland delineation was significantly improved over "on-the-ground" techniques given the aerial perspective afforded and the highly reflective (bright red signature) wetland vegetation in comparison to the senescing upland vegetation (blue, gray, or tan signature). 3.2 Summary of Proiect Area Characteristics The overall study area occupies the south headwater rim of the Axial basin (along the Danforth Hills) and generally drains to the northeast, eventually into the Yampa River which is tributary to the Green then Colorado Rivers. Elevations in the study area range from just below 6,400 feet +/- above mean sea level where Jubb Creek exits the study area to 8,567 at a high point along the ridge to the south. Typical stream gradients in the headwaters range from 3 to 5 percent but occasionally exhibit steeper reaches, and 1 to 3 percent along the alluvial floodplains lower in the watershed. Adjacent upland slopes range from moderately steep to steep (>35 % slope). Land uses noted in the area include: wildlife habitat, agriculture (grazing by cattle and sheep), coal exploration, and recreation. Most of the recreational land use is related to big game hunting that draws clientele from across Colorado and the United States. At the time of sampling perennial stream reaches were noted to include: Wilson Creek, Jubb Creek, and Collom Creek (including a majority of the East Fork of Collom). All other drainages were observed to be intermittent or ephemeral. It's possible that the upper portions of the main stem of Jubb Creek and Collom Creek are intermittent in most years as elevated moisture in 2005 may have led to an extension of annual flows. Perennial reaches generally exhibited a defined bed and bank and as such classify as a WUS, although some areas (especially Jubb Creek and lower Collom Creek) routinely exhibited a grass- lined channel that facilitates classification of the water course as a wetland rather than WUS. CEDAR CRZIZIXASMOAUSS, INC. Page 6 Colowyo Coal Co. - Collom Project Wetlands