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ephemeral Streams or by creating a depression within incipient drainageways. They are all in poor condition with incised emergency spillways. These ponds are discussed in [he Surface Water Rights • section of Tab 7. Condition, Capability, and Productivity. The Mine Permit Area is essentially classified as rangeland and is used by livestock for grazing from late June to mid-October and by wildlife (including deer and elkl for forage during the winter season, Elk and deer which winter on the Mine Permii Area have generally been observed on the southerly exposures or windblown ridges where snow does not accumulate and browse or dried forage such as grass or fortis are available. Again, big game aerial census flights do not indicate a preference for the mine or expansion area by big game during the winter. Small mammals and birds tend to utilize the study site throughout the year. On the south- and southwest-facing slopes and ridgetops, vegetation of the upland areas is composed primarily of sagebrush grassland communities Isee Photo 5, Appendix 4-11. Mixed brush and aspen communities appear on the more moist north- and northeast-facing slopes, however, mixed brush may occur on any area. Within the Mine Permit Area, sagebrush grassland and mixed brush are the dominant vegetation communities. Table 4-2 summarizes the forage production and carrying capacity for each vegetation community. These estimates are based an 1983, 1990, and 1997 clipped production data gathered by Western Resource Development Corp. and ESCO Associates, Inc. (see Tab 10, Vegetationl. The production • values presented in Table 4-2 reflect herbaceous production values only. Historically, this area has been used for grazing sheep, but a recent shift to cattle grazing has resulted in a relatively even balance of utilization between the two types of livestock. In the past, rather heavy grazing by livestock in the summer and browsing by wildlife in the winter has caused a deterioration in the range condition of the area. According to the Soil Conservation Service in 1974, rangeland in the Mine Permit Area was classified in "fair" condition, which is consistent for much of the rangeland in the area. It appears that current vegetation production rates in the Mine Permit Area exceed to some degree present grazing rates. If this is the case, range condition may eventually improve and result in an increased carrying capacity. For mare detailed information on this interface material, see Tab 10, Vegetation Survey and Tab 11, Wildlife Survey. • 13 Revised 9/98