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<br />III. AFFECTED ENVIRONMENT AND ENVIRONMENTAL
<br />CONSEQUENCES
<br />
<br />
<br />A. WATERSHED RESOURCES
<br />
<br />1. Affected Environment
<br />
<br />six watersheds comprise the project assessment area: Owl Creek, Spring Creek,
<br />East Fork, West Fork, Mainstem of Brush Creek and Snowmass Creek, Of these
<br />basins, the Spring Creek watershed, the eastern portion of the East Fork
<br />watershed, and the western portion of the Owl Creek watershed are undeveloped,
<br />
<br />No severe geologic hazards which might result in loss of life are present in the
<br />project area, but numerous lesser hazards exist which may affect the placement
<br />and design of structures, These hazards include unstable slopes, rockfall areas,
<br />and potentially unstable slopes, Landslide deposits are extensive with three
<br />areas of slope failures mapped on the upper slopes of Burnt Mountain, Two
<br />rockfall areas are present in the upper slopes of the project area, one just
<br />below Burnt Mountain and a second near the center of Burnt Mountain,
<br />
<br />Four areas of shallow groundwater are found along Spring Creek on upper Burnt
<br />Mountain, All alluvium in the East Village area is considered as having possible
<br />shallow groundwater, Artificial hazards such as upstream dams, underground
<br />mines, and large open pits do not occur in the project area, Earthquake hazards
<br />are moderate.
<br />
<br />Soil erosion is generally not a problem, except where runoff becomEos concentrated
<br />or the protective vegetation is removed or destroyed, RevegEotation can be
<br />difficult because of the high elevation, short and harsh growing season and lack
<br />of organic matter in the surface layers, Cirques and cliffs and large deposits
<br />of rock are found in the upper portions of the project area,
<br />
<br />Colorado River
<br />
<br />No aquatic species of concern (i.e., ColC)rado River cutthroat trout or threatened
<br />or endangered species) are found in the small streams within the Snowmass area,
<br />Four endanger$d species are, however, found downstream- in the Colorado River:
<br />the Colorado squawfish, humpback chub, bony tail chub, and razorback sucker,
<br />These species can be indirectly affected by flow depletions associated with
<br />snowmaking, on-mountain facilities, and off-site municipal uses,
<br />
<br />
<br />As discussed under "Related Permits, Plans and Actions" above, the Forest Service
<br />has received a draft Biological Opinion from USFWS which concluded that the
<br />proposed project is likely to jeopardize the continued existence of certain
<br />Colorado endangered fishes but that "reasonable and prudent alternatives"
<br />developed by the USFWS will offset this jeopardy,
<br />
<br />Sorina Creek Watershed
<br />
<br />Spring Creek, tributary to Owl Creek, has a watershed area of 2,034 acres (3,17
<br />square miles), There are 6,25 miles of streamcourses within this watershed, of
<br />which approximately one mile is the willow and Owl Creek Ditch, aIld 2,3 miles are
<br />intermitteIlt, Of the 1,018 acres on NFSL, 754 are withiIl the Burnt Mountain
<br />portion of the permit area,
<br />
<br />Spring Creek is a well-vegetated, largely undisturbed watershed with a high
<br />drainage density and a high percentage of wetland/riparian habitats, Some of the
<br />
<br />Summary . 26
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