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Vantage to Pomona Heights Chapter 4 230 kV Transmission Line Project FEIS Environmental Consequences PAGE 4-112 slopes are probably heavily used during winter. This area overlaps the route segment ROW corridor for 1.6 miles. Potential impacts 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 and during parturition when fawns are relatively immobile and vulnerable. 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. Impact levels to mule deer are anticipated to be moderate for the 1.6 miles of the route segment that overlap the designated concentration area. All habitat disturbance associated with Route Segment NNR-6o/NNR-6u would be located within the Regularly Occupied Habitat MU for Sage-Grouse. For either option construction activities would disturb less than1 percent of Regularly Occupied Habitat (Table 4.3-7). For Route Segment NNR-6o, anticipated disturbance includes 26.5 acres of suitable Sage-Grouse habitat and 4.1 acres of marginal habitat. Undergrounding Route Segment NNR-6u would increase the anticipated disturbance to 50.1 acres of suitable habitat and 7.3 acres of marginal habitat (Table 4.3-8). With the implementation of RDFs (Sections 4.3.3.1 and 4.3.3.2), habitat impact levels would be low for 2.3 miles and moderate for 4.1 miles. Existing perching, roosting and nesting sites for avian predators are available along Route Segment NNR- 6/NNR-6u from buildings, trees, and fences associated with developed areas and existing distribution and 230 kV H-frame transmission lines. Construction of Route Segment NNR-6o would require an estimated 48 new structures, all of which would be located within 0.25 mile of an existing transmission line (Table 4.3-5). Although the underground option would not require transmission towers, at both transitions between above-ground and underground transmission, a transition station would be required, resulting in approximately five acres of disturbance at each transition station. The estimated Sage-Grouse population range does not overlap the Route Segment NNR-6/NNR-6u ROW (Figure 3.3-4). Approximately 3.7 miles of Route Segment NNR-6/NNR-6U is within 4.0 miles of an active lek (Table 4.3-6). All new structures within 4.0 miles of the active lek would be visually obstructed by terrain and therefore not visible from the lek. The lek is described in Section 4.3.3.3 Sage-Grouse. With the implementation of RDFs (Sections 4.3.3.1 and 4.3.3.2), lek impact levels are anticipated to be low for 2.7 miles and moderate for 3.7 miles. 4.3.4.16 Route Segment NNR-7 All disturbance (38.1 acres) would occur within areas classified as sagebrush/perennial grassland; therefore, it was all considered long-term impact because sagebrush would recover very slowly following disturbance (Table 4.3-4). In 2014, a 23,261-acre fire burned the majority of Route Segment NNR-7. Because perennial bunchgrasses typically recover quickly after a fire and sagebrush typically recovers much more slowly. Currently much of the route segment is probably perennial grassland rather than shrubland—though depending on burn severity, over the next several years to several decades the sagebrush cover will likely return. RDFs would be implemented to minimize habitat loss and degradation, as described in Section 4.3.3.1. Impact levels to special status species habitat are expected to be low for 7.1 miles and moderate for 1.1 miles. The presence of new transmission 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