Kalispell-Kerr Transmission Line Rebuild Project Draft Environmental Assessment February 2015 DOE/EA-1961 This page deliberately left blank. Contents Chapter 1 Purpose of and Need for the Proposed Action ............................................................................... 1-1 1.1 Need for Action ............................................................................................................................ 1-1 1.2 Purposes of Action ....................................................................................................................... 1-1 1.3 Public Involvement and Issue Summary ...................................................................................... 1-2 Chapter 2 Proposed Action and Alternatives................................................................................................... 2-1 2.1 Existing Transmission Line ........................................................................................................... 2-1 2.1.1 Ongoing Line Maintenance ...................................................................................................... 2-1 2.1.2 Ongoing Vegetation Management ........................................................................................... 2-2 2.2 Proposed Action ........................................................................................................................... 2-2 2.2.1 Transmission Line Structures ................................................................................................... 2-3 2.2.2 Conductors, Optical Ground Wire, and Counterpoise ............................................................. 2-7 2.2.3 Temporary Staging Areas, Tensioning Sites, and Guard Structures ........................................ 2-8 2.2.4 Access Roads ............................................................................................................................ 2-9 2.2.5 Vegetation Removal ............................................................................................................... 2-10 2.2.6 Construction Sequencing and Scheduling .............................................................................. 2-11 2.3 No Action Alternative ................................................................................................................. 2-12 2.4 Alternatives Considered but Eliminated from Detailed Study ................................................... 2-12 2.5 Comparison of Alternatives ....................................................................................................... 2-13 Chapter 3 Affected Environment, Environmental Consequences, and Mitigation Measures ......................... 3-1 3.1 Introduction ................................................................................................................................. 3-1 3.2 Land Ownership, Use, Recreation, and Transportation ............................................................... 3-1 3.2.1 Affected Environment .............................................................................................................. 3-1 3.2.2 Environmental Consequences–Proposed Action ..................................................................... 3-8 3.2.3 Mitigation Measures .............................................................................................................. 3-12 3.2.4 Environmental Consequences–No Action Alternative ........................................................... 3-13 3.3 Geology and Soils ....................................................................................................................... 3-14 3.3.1 Affected Environment ............................................................................................................ 3-14 3.3.2 Environmental Consequences–Proposed Action ................................................................... 3-16 3.3.3 Mitigation Measures .............................................................................................................. 3-17 3.3.4 Environmental Consequences–No Action Alternative ........................................................... 3-18 3.4 Vegetation .................................................................................................................................. 3-19 3.4.1 Affected Environment ............................................................................................................ 3-19 3.4.2 Environmental Consequences–Proposed Action ................................................................... 3-26 3.4.3 Mitigation Measures .............................................................................................................. 3-28 3.4.4 Environmental Consequences–No Action Alternative ........................................................... 3-28 3.5 Wildlife ....................................................................................................................................... 3-30 3.5.1 Affected Environment ............................................................................................................ 3-30 3.5.2 Environmental Consequences–Proposed Action ................................................................... 3-36 3.5.3 Mitigation Measures .............................................................................................................. 3-41 3.5.4 Environmental Consequences–No Action Alternative ........................................................... 3-42 3.6 Wetlands and Floodplains .......................................................................................................... 3-43 3.6.1 Affected Environment ............................................................................................................ 3-43 3.6.2 Environmental Consequences–Proposed Action ................................................................... 3-44 3.6.3 Mitigation Measures .............................................................................................................. 3-49 Bonneville Power Administration i Contents 3.6.4 Environmental Consequences–No Action Alternative ........................................................... 3-49 3.7 Water Resources and Fish .......................................................................................................... 3-50 3.7.1 Affected Environment ............................................................................................................ 3-50 3.7.2 Environmental Consequences–Proposed Action ................................................................... 3-53 3.7.3 Mitigation Measures .............................................................................................................. 3-58 3.7.4 Environmental Consequences–No Action Alternative ........................................................... 3-58 3.8 Visual Quality ............................................................................................................................. 3-60 3.8.1 Affected Environment ............................................................................................................ 3-60 3.8.2 Environmental Consequences–Proposed Action ................................................................... 3-63 3.8.3 Mitigation Measures .............................................................................................................. 3-64 3.8.4 Environmental Consequences–No Action Alternative ........................................................... 3-64 3.9 Air Quality and Climate Change ................................................................................................. 3-65 3.9.1 Affected Environment ............................................................................................................ 3-65 3.9.2 Environmental Consequences–Proposed Action ................................................................... 3-67 3.9.3 Mitigation Measures .............................................................................................................. 3-69 3.9.4 Environmental Consequences–No Action Alternative ........................................................... 3-69 3.10 Socioeconomics and Public Services .......................................................................................... 3-70 3.10.1 Affected Environment ............................................................................................................ 3-70 3.10.2 Environmental Consequences–Proposed Action ................................................................... 3-73 3.10.3 Mitigation Measures .............................................................................................................. 3-75 3.10.4 Environmental Consequences–No Action Alternative ........................................................... 3-75 3.11 Cultural Resources ..................................................................................................................... 3-76 3.11.1 Affected Environment ............................................................................................................ 3-76 3.11.2 Environmental Consequences–Proposed Action ................................................................... 3-78 3.11.3 Mitigation Measures .............................................................................................................. 3-79 3.11.4 Environmental Consequences–No Action Alternative ..........................................................