Vantage to Pomona FEIS Index 34 - Laserfiche WebLink

Home Browse Search

Vantage to Pomona Heights Chapter 4 230 kV Transmission Line Project FEIS Environmental Consequences PAGE 4-106 The presence of new transmission line structures, which could provide additional perch and/or nesting sites for avian predators, could negatively impact nearby prey species such as small mammals and avian species, particularly when the new structures are built in an area where perching opportunities currently do not exist (i.e., greater than 0.25 mile from existing structures or trees). Construction of Route Segment NNR-3 would require an estimated 69 structures in a landscape dominated by low growing grasses and shrubs. Only an estimated five new structures would be located greater than 0.25 mile from an existing transmission line (Table 4.3-5). Within one mile of Route Segment NNR-3, potentially suitable habitat is present for 49 special status wildlife species that are possible, likely, or known to occur (Tables 3.3-2, 3.3-3, and 3.3-7). Potential impacts and RDFs to address them are discussed in Sections 4.3.3.1 and 4.3.3.2. Species or wildlife resources that have been documented at specific locations within one mile of Route Segment NNR-3 include bull trout critical habitat, steelhead critical habitat (Middle Columbia River DPS), cliff bands with high concentrations of nesting raptors, several golden eagle nests within four breeding territories, a historic ferruginous hawk nest, a pallid bat acoustical detection, and winter range for bighorn sheep, elk, and mule deer. Critical habitat for bull trout occurs within one mile of Route Segment NNR-3 in the Yakima River. Bull trout are not known to spawn within streams within the Project area because the streams are too small and not cold enough over a long enough time period to provide suitable spawning and rearing habitat; however, bull trout could use streams for short periods for foraging (AECOM Environmental 2010). No transmission line structure or road construction work would occur directly within the Yakima River. Erosion would be minimized by applying and maintaining standard erosion and sediment control methods. The implementation of RDFs is anticipated to be effective at eliminating impacts to bull trout. No identifiable impacts to bull trout or bull trout habitat are anticipated to occur through construction, operation, and maintenance of the proposed Project. Within one mile of Route Segment NNR-3, the Yakima River and lower Burbank Creek are designated Critical Habitat for the Middle Columbia River steelhead DPS. No structure or road construction work would occur directly within the Yakima River, which is located greater than or equal to 0.75 mile from the route segment ROW corridor or Burbank Creek, which would be spanned by the route segment. Erosion would be minimized by applying and maintaining standard erosion and sediment control methods. No identifiable impacts to steelhead or its habitat are anticipated to occur through construction, operation, and maintenance of the proposed Project. Cliff bands occur along Selah Creek and tributaries, Lmuma Creek, and the Yakima River Canyon within one mile of Route Segment NNR-3. The cliffs attract high concentrations of raptors, including prairie falcons (not a special status species, but sensitive to nest disturbance) and several golden eagle nests associated with four territories: one on Selah Creek (0.9 mile away from centerline), one on Lmuma Creek (0.1 mile away from centerline), and two in the Yakima River Canyon (0.8 mile away from centerline). A historic ferruginous hawk nest was documented in 1994 on top of a six-foot rock outcrop approximately 0.3 mile from the route segment. Cliffs would be spanned, thus, avoiding direct disturbance to the habitat. Within the breeding season, construction would be avoided within species- specific raptor nest buffers to avoid disturbing nesting birds (0.5 mile for golden eagle and ferruginous hawk and 0.25 mile for prairie falcon; see RDFs in Chapter 2). Impact levels on golden eagles are anticipated to be moderate for 3.8 miles and impact levels on ferruginous hawks are expected to be moderate for 1.8 miles. Two pallid bats were detected in 1994 approximately 0.7 miles east of Route Segment NNR-3 along Selah Creek. Although the detections were near the riparian vegetation in Selah Creek, the species commonly uses upland habitats like sagebrush-steppe, as well. The route segment would span the Selah