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Vantage to Pomona Heights Chapter 4 230 kV Transmission Line Project FEIS Environmental Consequences PAGE 4-104 acres of areas classified as sagebrush/perennial grassland, 2.4 acres of sagebrush/annual grassland, and 1.3 acres of tree habitat. RDFs would be implemented to minimize further habitat degradation, as described in Section 4.3.3.1. Impact levels to habitat are expected to be low for 3.4 miles and moderate for 1.7 miles (0.9 mile of sagebrush/perennial grassland, 0.5 mile of sagebrush/annual grassland, and 0.3 mile of tree habitat). 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-2 would require an estimated 48 structures in a landscape dominated by low growing grasses and shrubs. An estimated 21 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-2, potentially suitable habitat is present for 40 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-2 include the Selah Waterfowl Concentration Area/East Selah Wetlands, cliff bands with high concentrations of nesting raptors including golden eagles and prairie falcons, a burrowing owl nesting site, black-tailed jackrabbits, and pallid bats. Cliff bands occur along Selah Creek and tributaries within one mile of Route Segment NNR-2; the cliffs attract high concentrations of raptors; documented nests include four prairie falcon nests (not a special status species, but sensitive to nest disturbance); and one golden eagle nest documented by PHS in 2013 just under one 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 0.25 mile for prairie falcon; see RDFs in Chapter 2). Impact levels on golden eagles are anticipated to be moderate for 0.4 mile. A historic burrowing owl nesting site (last documented occupancy in 1993) occurs approximately 0.75 mile from Route Segment NNR-2. While this particular nest is not likely to have persisted to the present, it demonstrates potential for burrowing owls to nest within one mile of Route Segment NNR-2. Potential impacts would occur from disturbance during construction activities or from injury or mortality from vehicle strikes or interactions with other equipment used during construction, including mechanical disturbance or crushing of burrows. If an occupied burrowing owl nesting site is found within 0.25 mile of the route segment’s ROW corridor, a seasonal restriction on construction would be enacted from March to August within the 0.25-mile buffer. Additional RDFs to reduce impact on burrowing owls are described in Sections 4.3.3.1 and 4.3.3.2. Impact levels to burrowing owl are expected to be moderate for 1.4 miles. The Selah Waterfowl Concentration Area/East Selah Wetlands associated with the Yakima River are located within one mile—approximately 0.8 mile west of Route Segment NNR-2. Four special status aquatic bird species are likely to utilize the area, including great blue heron, eared grebe, tundra swan, and American white pelican. Waterfowl and aquatic bird injury and mortality could occur through collision with the new transmission line, though it is not very likely because the route segment will not cross the wetlands or cross between the wetlands and likely feeding areas such as agricultural fields. RDFs include installing bird flight diverters in locations with known avian mortality through collision with transmission line infrastructure. Route Segment NNR-2 is expected to have no identifiable impacts to waterfowl or aquatic bird species.