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Vantage to Pomona Heights Chapter 4 230 kV Transmission Line Project FEIS Environmental Consequences PAGE 4-116 crowned night heron; great blue heron; Clark’s, western, and eared grebes; tundra swan; American white pelican; and common loon. Common loons and American white pelicans have been specifically documented within one mile of Route Segment NNR-8. Waterfowl and aquatic bird injury and mortality could occur through collision with the new transmission line. Where the proposed route segment ROW corridor crosses the Columbia River, the new transmission line would parallel four existing transmission lines within 350 to 1,300 feet. To the extent that collision potential exists, the additional line will likely not add greater risk than what already occurs at the crossing. RDFs include installing bird flight diverters in locations with known avian mortality through collision with transmission line infrastructure. NNR-8 is expected to have no identifiable impacts to waterfowl or aquatic bird species. Black-tailed jackrabbit has been documented within one mile of Route Segment NNR-8. Potential impacts include a reduction and degradation of habitat, disturbance and displacement from habitats, increased predation from avian predators, increased human activity, introduction and spread of noxious weeds, and injury or mortality due to collision with construction equipment. RDFs to address the impacts are described in Sections 4.3.3.1 and 4.3.3.2. Impact levels to black-tailed jackrabbits are expected to be moderate for 1.5 miles and low for 0.6 mile. A mule deer regular concentration area has been identified on Wanapum Bench within one mile of Route Segment NNR-8, immediately north of the Vantage Substation. The PHS data indicates year-round use of this area. This area comes within approximately 0.1 mile of the proposed route, but does not intersect the route segment ROW corridor. Potential impacts to mule deer include habitat loss, habitat degradation from the spread of invasive weeds, collision with vehicles during construction and maintenance, and disturbance during construction and maintenance. Mule deer are most likely to be impacted by disturbance during winter when increased energy expenditure may lower survival. Adherence to seasonal restrictions from December 1 to March 1 on construction activities within the designated concentration area should minimize disturbance impacts to mule deer. No identifiable impacts are anticipated to occur to mule deer through construction, operation and maintenance of the proposed Project. The majority of the habitat disturbance associated with Route Segment NNR-8 would be located within the Occasionally Occupied Habitat MU for Sage-Grouse (10.6 acres), with the remainder of disturbance within Regularly Occupied Habitat MU (2.7 acres) Construction activities would disturb less than one percent of Regularly Occupied Habitat (Table 4.3-7). Anticipated ground disturbance includes 8.9 acres of suitable Sage-Grouse habitat, and 4.4 acres of marginal habitat (Table 4.3-8). With the implementation of RDFs (Sections 4.3.3.1 and 4.3.3.2), the scale of disturbance and degradation to Sage-Grouse habitat is anticipated to be low for 1.2 miles and moderate for 1.5 mile. Existing perching, roosting, and nesting sites for avian predators are available along Route Segment NNR-8 from buildings, trees, and fences associated with developed areas and existing distribution and 230 kV H-frame transmission lines. Construction of Route Segment NNR-8 would require an estimated 20 new structures, but none of them would be located greater than 0.25 mile from an existing transmission line (Table 4.3-5). The estimated Sage-Grouse population range does not overlap the Route Segment NNR-8 ROW (Figure 3.3-4). No active leks are known to occur within four miles of Route Segment NNR-8 (Table 4.3-6). With the implementation of RDFs (Sections 4.3.3.1 and 4.3.3.2), impacts to lekking Sage-Grouse associated with the construction of Route Segment NNR-8 is anticipated to be low for the entire length of the route segment (2.7 miles). 4.3.4.18 Route Segment MR-1 Approximately 50.7 acres of long-term and 28.5 acres of short-term disturbance would occur through the construction of Route Segment MR-1. Permanently disturbed areas would include 29.3 acres of