BONNEVILLEPOWERADMINISTRATION Midway-Moxee Rebuild and Midway-Grandview Upgrade Transmission Line Project Draft Environmental Assessment July 2015 DOE/EA-1951 This page left intentionally blank Table of Contents Page List of Appendices ................................................................................................................................. vi List of Tables ........................................................................................................................................ vii List of Figures ....................................................................................................................................... ix Chapter 1 Purpose of and Need for Action ............................................................................................ 1-1 1.1. Introduction ............................................................................................................................ 1-1 1.2. Background ............................................................................................................................ 1-1 1.3. Need for Action ...................................................................................................................... 1-1 1.4. Purposes of Action ................................................................................................................. 1-2 1.5. Agency Roles ......................................................................................................................... 1-4 1.5.1. Lead and Cooperating Agencies ...................................................................................... 1-4 1.5.2. Other Agencies that may Use this Environmental Assessment ....................................... 1-4 1.6. Public Involvement ................................................................................................................. 1-5 1.6.1. Project Scoping Process ................................................................................................... 1-5 1.6.2. Distribution, Review, and Comment for the Draft Environmental Assessment ............ 1-10 1.7. Draft Environmental Assessment Content and Organization ............................................... 1-10 Chapter 2 Proposed Action and Alternatives ........................................................................................ 2-1 2.1. Overview of the Proposed Action and No Action alternatives .............................................. 2-1 2.2. Elements of the Proposed Action ........................................................................................... 2-2 2.2.1. Transmission Line Rights-of-Way ................................................................................... 2-8 2.2.2. Transmission Line Structures ........................................................................................ 2-11 2.2.3. Guy Wires and Anchors ................................................................................................. 2-15 2.2.4. Conductor, Overhead Ground Wire, Fiber Optic Cable, and Counterpoise .................. 2-15 2.2.5. Access Road Work ......................................................................................................... 2-18 2.2.6. Vegetation Management During Construction .............................................................. 2-20 2.2.7. Staging Areas ................................................................................................................. 2-22 2.2.8. Revegetation of Areas Disturbed by Construction ........................................................ 2-22 2.2.9. Waste Management ........................................................................................................ 2-22 2.2.10. Proposed Construction Schedule ................................................................................... 2-22 2.2.11. Ongoing Maintenance and Vegetation Management ..................................................... 2-23 2.3. No Action Alternative .......................................................................................................... 2-24 2.4. Alternatives Considered but Eliminated from Detailed Study ............................................. 2-25 2.5. Comparison of Alternatives .................................................................................................. 2-27 2.6. Summary of Impacts Table .................................................................................................. 2-28 Bonneville Power Administration i Chapter 3 Affected Environment, Environmental Consequences, and Mitigation Measures ......................................................................................................................... 3-1 3.1. Introduction ............................................................................................................................ 3-1 3.2. Land Use and Recreation ....................................................................................................... 3-2 3.2.1. Affected Environment ...................................................................................................... 3-2 3.2.2. Environmental Consequences – Proposed Action ........................................................... 3-6 3.2.3. Mitigation Measures – Proposed Action .......................................................................... 3-8 3.2.4. Unavoidable Impacts Remaining After Mitigation – Proposed Action ........................... 3-9 3.2.5. Environmental Consequences – No Action Alternative .................................................. 3-9 3.3. Transportation ........................................................................................................................ 3-9 3.3.1. Affected Environment ...................................................................................................... 3-9 3.3.2. Environmental Consequences – Proposed Action ......................................................... 3-10 3.3.3. Mitigation Measures – Proposed Action ........................................................................ 3-10 3.3.4. Unavoidable Impacts Remaining After Mitigation – Proposed Action ......................... 3-11 3.3.5. Environmental Consequences – No Action Alternative ................................................ 3-11 3.4. Socioeconomics, Environmental Justice, and Public Services ............................................. 3-11 3.4.1. Affected Environment .................................................................................................... 3-11 3.4.2. Environmental Consequences – Proposed Action ......................................................... 3-15 3.4.3. Mitigation Measures – Proposed Action ........................................................................ 3-18 3.4.4. Unavoidable Impacts Remaining After Mitigation – Proposed Action ......................... 3-19 3.4.5. Environmental Consequences – No Action Alternative ................................................ 3-19 3.5. Noise ..................................................................................................................................... 3-19 3.5.1. Affected Environment .................................................................................................... 3-19 3.5.2. Environmental Consequences – Proposed Action ......................................................... 3-23 3.5.3. Mitigation Measures – Proposed Action ........................................................................ 3-25 3.5.4. Unavoidable Impacts Remaining After Mitigation – Proposed Action ......................... 3-25 3.5.5. Environmental Consequences – No Action Alternative ................................................ 3-25 3.6. Public Health and Safety ...................................................................................................... 3-26 3.6.1. Affected Environment .................................................................................................... 3-26 3.6.2. Environmental Consequences – Proposed Action ......................................................... 3-29 3.6.3. Mitigation Measures – Proposed Action ........................................................................ 3-32 3.6.4. Unavoidable Impacts Remaining After Mitigation – Proposed Action ......................... 3-33 3.6.5. Environmental Consequences – No Action Alternative ................................................ 3-33 3.7. Geology and Soils ................................................................................................................ 3-34 3.7.1. Affected Environment .................................................................................................... 3-34 3.7.2. Environmental Consequences – Proposed Action ......................................................... 3-35 3.7.3. Mitigation Measures – Proposed Action ........................................................................ 3-37 3.7.4. Unavoidable Impacts Remaining After Mitigation – Proposed Action ......................... 3-38 ii Midway-Moxee Rebuild and Midway-Grandview Upgrade Transmission Line Project EA 3.7.5. Environmental Consequences – No Action Alternative ................................................ 3-38 3.8. Vegetation ............................................................................................................................ 3-38 3.8.1. Affected Environment ...................................................................................................