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Vantage to Pomona Heights Chapter 4 230 kV Transmission Line Project FEIS Environmental Consequences PAGE 4-59 The Required Design Features (RDFs) and environmental protection measures described in Section 2.3 - Required Design Features Common to Action Alternatives have been incorporated into the Project design and would be implemented during construction and operation of the proposed Project. These measures are designed to avoid or minimize environmental impacts from Project construction, operation, and maintenance activities and are items that Pacific Power has committed to implement as part of the Project development. RDFs will be reviewed, revised, and developed further, as appropriate, to reduce impacts associated with specific resource concerns (e.g., cultural, biological, visual resources) and will be included in the Plan of Development (POD) for this Project. The POD will be reviewed and approved by state, county, and federal agencies and made a part of the authorizations to be issued by these agencies for the proposed Project. Initial impacts described below take into account the implementation of these RDFs. 4.3.3.1 Habitat Construction of the proposed Project and associated infrastructure could result in degradation and loss of wildlife habitat through direct and indirect impacts. Habitat loss for a given species would occur in areas where vegetation is completely removed or becomes altered such that a given wildlife species is unlikely to use it. Degradation of habitat could occur if vegetation composition and/or structure within currently suitable habitat becomes altered and does not adequately meet food and cover requirements. The two primary causes of habitat degradation that have potential to occur as a result of the Project are spread of invasive weeds and altered fire regimes. Direct Habitat Loss Direct habitat loss would result from temporary trampling of herbaceous vegetation and removal of vegetation due to construction of the transmission line, access roads, and temporary work spaces. Vegetation would be permanently removed and disturbed at structure bases and along permanent access roads. Vegetation removal could have a variety of effects on habitat including changes in community structure and composition. The degree of impact depends on the type and amount of vegetation affected and the rate at which vegetation would regenerate after construction. Within the Project study area, the recovery of vegetation following revegetation would vary by plant community type following construction. Grasslands and herbaceous wetlands would generally recover within five to seven years, while shrublands (e.g., sagebrush [Artemesia spp.]) may require 30 to 120 years, depending on the subspecies and size of disturbance (Olson et al. 2000; Lesica et al. 2005; Baker 2006; Knick and Connelly 2011). Because all of the Project Action Alternatives parallel existing transmission lines for at least part of their length, utilizing nearby existing roads will reduce the need for new access roads, thus decreasing the amount of direct habitat loss associated with the proposed Project. RDFs implemented during construction and operation are anticipated to be effective at minimizing the amount of vegetation that would be impacted (refer to Section 2.3 - Required Design Features Common to Action Alternatives). RDFs include: minimizing construction sites within native plant communities; maintaining intact vegetation wherever possible; minimizing the blading of native plant communities during construction while being consistent with safe construction practices; utilizing overland travel where feasible; and reseeding disturbed areas using an agency- approved mixture of native and non-native species or seed for revegetation as detailed in the POD. Direct habitat disturbance is presented in Table 4.3-4 and discussed for each route segment in Section 4.3.4. Indirect Habitat Degradation Indirect impacts to habitat could occur during construction through the generation of fugitive dust. High levels of fugitive dust can impact the growth of some organisms (reduced photosynthesis) and can impact drinking water. Most impacts from fugitive dust would last only until the next rain event when the dust is washed away and diluted. Potential impacts from the generation of fugitive dust would be transient as construction progresses and would not occur in one area for a long duration. Prior to construction, a Dust Control Plan would be developed as part of the POD and would identify dust control measures to be