2013-11-04_PERMIT FILE - C1981022 (18)

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3.0 RESULTS ANO DISCUSSION 3.1 ENVIRONMENTAL CHARACTERISTICS The Somerset Mine is located in the valley of the North fork of the Gunnison River at an elevation of approximately 6100 feet. The area overlapping the underground working includes several steep south-facing ridges which range to approximately 8000 feet in elevation. The ridges are dissected by south-flowing drainages such as Hubbard, Bear, and Elk Creeks, respectively fran west to east. These small streams have carved steep east-facing and west-facing slopes in the major ridges. The climate of the area is semi-arid and receives an annual precipi- tation of approximately 12 to 15 inches. See Table 1. Precipitation is rather evenly distributed throughout the year with peaks In the late summer-early fall end spring months. Mean temperature below freezing extends from December through February. This periotl represents the snow accumulation season. The growing season, approximately 140 days duration, is relatively short, However, the variation in the aspect of ridges at the mine area modify this figure. The south- and west- facing slopes have a longer growing season. The mine area is located in a region mapped as Pinyon-Juniper by • Kuchler 119661 and Shelford 119631. This broad scale mapping is generally accurate for west- and southwest-facing slopes. The pinyon pine Pinuo edalia element of the vegetation type is, however, missing from the community of the mine area. East- and southeast-facing slopes, the moister exposures, are characterized by a Mountain Shrubland vege- tation type dominated by GamDel oak fl~~e~cua gumGe~ii. Woody trees characteristic to riparian areas are sparsely represented along the drainages. A true riparian vegetation type, however, has not developed due to the scarcity of wafer in the stream and the general absence of suitable alluvium. The higher elevations and moist east-facing slopes support a conifer community of Douglas-fir pneudulnuya m¢n~ieeii and some subalpine fir ,iGie~ .(aniucuapu. Aspen ~u~wLu.+ t.avmuLu%de~ occur at nigher elevations and on north-facing slopes at lower elevations. See Figure 1, Vegetation Map. These native vegetation types Historically have been used as renge- land for the grazing of livestock while providing habitat for wildlife and serving as a hunting area For sportsmen. In general, the mine area has been overgrazed in the past. Many of the more palatable native grass species nave been eliminated and replaced by less valuable introduced species. 3.2 DESCRIPTION OF VEGETATION • ' Mining activities have created disturbances in the Mountain ShrUb- tend and Juniper Woodland vegetation types. See Table 2. The following -ti-