2012-01-06_PERMIT FILE - C1982057A (3)

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• understory species including western wheatgrass, bluebunch wheatgrass, arrowleaf balsamroot, silvery lupine, and American vetch. A discussion of various vegetative parameters generally associated with this type may be found in Appendix 10-8. Meadow (disturbed). In the spring of 1985, the failure of the Sage Creek Reservoir dam caused extensive flooding on the downstream course of Sage Creek. The 7.6 acres of the disturbed meadow type shown on revised Exhibit 10-2 reflects the area affected by the Sage Creek floodwaters and associated sediment deposition. After the sediment and surrounding areas had sufficiently dried out, minor rehabilitation work was carried out. This included repair of any necessary fences, tillage of areas where possible, and either seeding permanent vegetation or allowing natural regeneration to reestablish vegetation. Though it has been four growing seasons since the flood affected the area, the species composition of much of the area is still indicative of disturbance. Commonly occurring species are Canada thistle, cocklebur (Xanthi um sp.), dogba ne (Apocynum sp.), wild lettuce, knotweed, western wheatgrass, meadow and foxtail barley, and quackgrass. Common species in the seeded areas include smooth brome, timothy, and orchardgrass. This disturbed vegetation type will be completely affected by the haul road and associated • construction and will be reclaimed as shown on Exhibit 22-2 in Tab 22. Riparian (disturbed). The disturbed riparian type reflects a zone of vegetation of varying area that occurs adjacent to the channel of Sage Creek. This type is found on approximately 2.2 acres in the haul road corridor permit area (see revised Exhibit 10-2 ). Like the disturbed meadow type, it was heavily affected by the Sage Creek flood in 1985. Since that time, the aggressive species sandbar willow (Salix exigua), has established a near monoculture in the type. Other common species include Canada thistle and Kentucky bluegrass. This type will not be greatly affected by the established haul road because of the final alignment location, stream buffer zone considerations, and the proximity of Sage Creek. See Tab 12, Transportation Facilities (page 12-19) for a discussion of Stream Buffer Zones. Existing Roads. Approximately 3.0 acres of roads are found in the far eastern portion of the haul road corridor permit area. These include the permanent county road and the existing haul road used to deliver coal to the Hayden Station. • Plant Species List. Presented in Table 10-5 are the plant species observed during May 1974, June-AUgust 1979, August-September 1980, and the 1983 field studies. Included are 29