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White Salmon Interstate Bridge Replacement Project TS&L Type, Size, and Location TSP Transportation System Plan TSS Total Suspended Solids U.S

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White Salmon Interstate Bridge Replacement Project TS&L Type, Size, and Location TSP Transportation System Plan TSS Total Suspended Solids U.S ODOT Key No.: 21280 This page intentionally left blank. This page intentionally left blank. Notice of Document Availability This Supplemental Draft EIS is available for review at the following locations: Port of Hood River (by appointment) 1000 E. Port Marina Drive Hood River, OR 97031 Note: Washington residents can contact the Port to schedule an appointment to view the document in Klickitat County White Salmon Valley Community Library (limited services during the COVID-19 pandemic) 77 NE Wauna Avenue White Salmon, WA 98672 Stevenson Community Library (limited services during the COVID-19 pandemic) 120 NW Vancouver Avenue Stevenson, WA 98648 These documents are also available on the Project website: https://portofhoodriver.com/bridge/bridge-replacement- project/. At the time of publication, Port of Hood River offices are closed due to COVID-19. If you would like to review a hard copy of the Supplemental Draft EIS, please contact the Port at [email protected] or 541-386-1645 to make arrangements for review of the hard copy. The Supplemental Draft EIS can also be viewed at the White Salmon Valley Community Library and the Stevenson Community Library which are open with limited services during the COVID-19 pandemic. How to Submit Comments Written comments on the Supplemental Draft EIS can be submitted during the public comment period (November 20, 2020, through January 4, 2021) by email to [email protected] or regular mail to: Hood River Bridge Supplemental Draft EIS Kevin Greenwood Port of Hood River 1000 E. Port Marina Drive Hood River, OR 97031 Comments can be submitted orally and in writing at the public hearing for the Supplemental Draft EIS on December 3, 2020. Comments may also be submitted by leaving a voice message on the Port’s Supplemental Draft EIS comment line at 833-215- 2352 (toll-free). Table of Contents Executive Summary .......................................................................................................................................... ES-1 Project Description and Location .............................................................................................................. ES-1 Purpose and Need .................................................................................................................................... ES-2 Lead and Cooperating Agencies ................................................................................................................ ES-2 Tribal Consultation .................................................................................................................................... ES-3 Public Involvement ................................................................................................................................... ES-4 Alternatives Considered ............................................................................................................................ ES-4 Construction of the Build Alternatives .................................................................................................... ES-17 Beneficial and Adverse Impacts .............................................................................................................. ES-17 Permits and Approvals Needed .............................................................................................................. ES-20 Additional Compliance Processes Underway and Unavailable Information ........................................... ES-20 Next Steps ............................................................................................................................................... ES-21 1. Purpose and Need for Proposed Action ................................................................................................ 1-1 1.1. Introduction to the Project ........................................................................................................... 1-1 1.2. Purpose and Need ........................................................................................................................ 1-4 1.3. Goals and Objectives .................................................................................................................... 1-6 1.4. Organization of the Supplemental Draft EIS ................................................................................. 1-7 1.5. Next Steps ..................................................................................................................................... 1-7 2. Alternatives .......................................................................................................................................... 2-1 2.1. Description of Alternatives ........................................................................................................... 2-1 2.2. Construction of the Build Alternatives ........................................................................................ 2-15 2.3. Alternatives Development and Screening ................................................................................... 2-18 2.4. Alternatives Considered but Dismissed ...................................................................................... 2-20 2.5. Identification of Preferred Alternative ........................................................................................ 2-22 2.6. Status of the Short-term and Mid-term Improvements Identified in the Draft EIS .................... 2-22 2.7. Additional Compliance Processes Underway and Unavailable Information ............................... 2-23 2.8. Permits and Approvals ................................................................................................................ 2-24 3. Affected Environment, Environmental Consequences, and Mitigation ................................................... 3-1 3.1. Traffic Operations ......................................................................................................................... 3-1 3.2. Safety: Vehicle Travel, Emergency Response, River Navigation, and Seismic Resiliency ............ 3-10 3.3. Pedestrian, Bicycle, and Regional Transit Access ........................................................................ 3-13 3.4. Land Use ..................................................................................................................................... 3-16 3.5. Treaty Fishing Rights ................................................................................................................... 3-26 3.6. Geology and Soils ........................................................................................................................ 3-38 3.7. Waterways and Water Quality .................................................................................................... 3-41 Hood River – White Salmon Interstate Bridge Replacement Supplemental Draft EIS i 3.8. Community and Social Resources ............................................................................................... 3-45 3.9. Environmental Justice Populations ............................................................................................. 3-49 3.10. Local and Regional Economies .................................................................................................... 3-57 3.11. Park and Recreation .................................................................................................................... 3-60 3.12. Section 6(f) Properties ................................................................................................................ 3-65 3.13. Historic Resources ...................................................................................................................... 3-67 3.14. Archaeological Resources and Traditional Cultural Properties ................................................... 3-72 3.15. Energy ......................................................................................................................................... 3-75 3.16. Vegetation and Wetlands ........................................................................................................... 3-77 3.17. Fish and Wildlife ......................................................................................................................... 3-83 3.18. Air Quality and Greenhouse Gases ............................................................................................. 3-93 3.19. Visual .......................................................................................................................................... 3-96 3.20. Noise and Vibration .................................................................................................................. 3-107 3.21. Hazardous Materials ................................................................................................................. 3-111 3.22. Irreversible and Irretrievable Commitment of Resources ......................................................... 3-115 3.23. Relationship between Local Short-Term Uses of the Human Environment and the Maintenance and Enhancement of Long-Term Productivity .................................................... 3-116 4. Cumulative Impacts .............................................................................................................................. 4-1 4.1. Analysis of Cumulative Impacts .................................................................................................... 4-1 4.2. Results of Cumulative
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