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Vantage to Pomona Heights Chapter 4 230 kV Transmission Line Project FEIS Environmental Consequences PAGE 4-119 desired biological objectives are not achieved with the existing RDFs, additional mitigation measures may be implemented. 4.3.6 Impact Summary By Alternative 4.3.6.1 No Action Alternative Under the No Action Alternative, the proposed Project would not be constructed or operated. No Project- related impacts to wildlife would occur, but changes in habitat and species composition would continue as a result of current conditions and future development. JBLM YTC would continue to use the majority of the Project area for military maneuvers and live fire training. Refer to Section 4.17 - Cumulative Effects for a discussion of potential future development. 4.3.6.2 Action Alternatives Table 4.3-9 presents a summary of the impacts for the Action Alternatives on all wildlife and Table 4.3- 10 presents a comparison of the impacts to Sage-Grouse. Each comparison includes nine Action Alternatives (Alternatives A-H and the NNR Alternative) and three design options under the NNR Alternative (NNR Alternative - Overhead Design Option, NNR Alternative - Underground Design Option, and NNR Alternative - MR Subroute). The NNR-Overhead Design Option is the Agency Preferred Alternative. The tables also tally the number of miles for each overall impact level (high, medium, low) that would be attributed to the Project following the implementation of RDFs for all wildlife species (Table 4.3-9) and for Sage-Grouse (Table 4.3-10). The NNR Alternative – Overhead Design Option and the NNR Alternative - Underground Design Option is the shortest Action Alternative (40.3 miles). Alternatives A-H are all longer than 60 miles, with Alternative H being the longest at 66.7 miles. As a result, the Agency Preferred Alternative (NNR Alternative - Overhead Design Option) would result in the least amount of direct disturbance to wildlife habitat (204 acres) and Sage-Grouse habitat (192 acres; suitable and marginal habitat) and the second fewest number of transmission line structures (328). While the NNR Alternative - Underground Design Option would require the fewest number of new structures (251), compared with the Agency Preferred Alternative, it would disturb more wildlife habitat (254 acres vs. 204 acres) and more Sage-Grouse habitat (243 acres vs. 192 acres) because it would require more vegetation removal through the excavation of a continuous trench for the underground portions and would require a permanent road to access the underground portions. Because the NNR Alternative – Overhead Design Option and the NNR Alternative - Underground Design Option closely parallel Pacific Power’s existing Pomona-Wanapum 230 kV transmission line for the majority of its total length, utilizing nearby existing roads will greatly reduce the need for the construction of new access roads, decreasing the amount of direct habitat loss associated with the proposed Project. The NNR Alternative - MR Subroute is 47.7 miles long and would result in 260 acres of direct disturbance to wildlife habitat, 230 acres of direct disturbance to Sage-Grouse habitat, and 383 new structures. The much lengthier Alternatives A-H would each result in at least 317 acres of direct wildlife habitat loss, at least 477 new transmission line structures, and from 203 acres (Alternative C) to 296 acres (Alternative F) of direct Sage-Grouse habitat loss. For all Action Alternatives, disturbed areas would be restored following construction; however, because of the long recovery times for restoring sagebrush communities (30 to 120 years), any direct disturbance to sagebrush-steppe would be considered a long-term impact. Indirect habitat loss through the spread of noxious weeds and invasive species and potential increased fire frequency would occur for all Action Alternatives. Ground disturbance and vegetation removal increase the potential for the introduction and spread of noxious and invasive weeds, with disturbed areas, such as roads and construction work areas, acting as conduits for weeds to become established in native habitats adjacent to the disturbed areas. Thus, indirect habitat loss through weed spread would be expected to