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Aspen Highltmds SA; Are. - Draft En.irorunelllaJ Impac' Slale""'IIl In order 10 minimize disturbance of ground cover along lift lines. cleared timber will be removed using environmentally sensitive techniques. including helicopters where there is no road access. In addition. glading will be limited in stands that have been ideotified as potential or recruiunent old growth to [Tlinimi7e the loss of shade-tolerant species in dense forested stands. WETLAND RESOURCES AFFECTED ENVIRONMENT Three classes of jurisdictional WlIIaS of the U.S. (wetlands. streams. and channels) occur in the Aspen Highlands analysis area. In addition. riparian zooes commonly occur in association with streams and channels. Few jurisdictional wetlands were identified in areas potentially affected by the proposed expansion. In the analysis area. wetlands occur as groundwater seep/spring areas and as narrow corridors along several of the stream courses. There are five perennial and intermittent streams fed by groundwater in the analysis area; three occur on the east side of Aspen Highlands Mountain, one is on the west side. and one occurs near the base area. During normal years. there is typically surface water present over portions or all of the stream courses during most of the seasons. The two types of riparian zones occurring in the analysis area include those that border streams beyond the narrow wetland fringe. and those found in swales and ravines that occur across the mountain. Often ravines occur in the bottom of avalanche chutes and arc dominated by dense willow thickets. ENVIRONMENTAL CONSEQUENCES Uoder the No Action Alternative, there would be 00 identifiable impact to wetlands in the analysis area. Five acres of wetland/riparian areas could be affected under Alternative B by (ow intensity glading or ski over. Direct impacts on jurisdictional wetlands would potentially affect two small intermittent streams with a small adjacent wetland (two crossings about 10 feet long and 22 feet wide). and one channel which is a dry watercourse except during precipitation or run-off events (two crossings 10 feet long and 22 feet wide). Together these crossings would necessitate about 0.02 acres of dredge and fill. The same 5 acres of wetland/riparian areas would be affected WIder Alternatives B and C by low intensity glading or ski over. Direct impacts under Alternative C would affect at least three features with six separate crossings. These include two intermittent streams (with a total of four crossings 10 feet long and 22 feet wide) and the same channel as affected in Alternative B (four crossings 10 feet long and 22 feet wide). Together these disturbances would require 0.04 acres of dredge and flll. POTENTIAL MITIGATION MEASURES To reduce dredging and fllling impacts to wetlands, wetlands should be avoided whenever possible. by minimizing size of individual impacts. and by constructing bridges to cross linear wetland features. Wetland losses would also be mitigated as required by the ACOE during Section 404 permitting. WILDLIFE AFFECTED ENVIRONMENT The determination of whether or not a given vegetation cover type comprises suitable wildlife habitat depends largely on the structural attributes of individual stands or patches of that type. including tree size and density. percent canopy coverage. snag (dead tree) density, and stand area. The WRNF has identified management indicator species (MIS) to help monitor specific habitat types and the group of species associated with each habitat type. They include the southern red-backed vole. snowshoe hare. white-tailed ptarmigan. golden eagle. yellow warbler. and the mountain chickadee. Elk. mule deer. highorn sheep. black bear. and blue grouse are also 20 Seclion III Wildlife