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I-405 Corridor Program - NE 8th St. to SR 520 Improvement Project Environmental Assessment

I-405, NE 8th St. to SR 520 Improvement Project Environmental Assessment

On May 7, 2008, WSDOT published an Environmental Assessment for the SR 520 to NE 8th St. Improvement Project. The Environmental Assessment contains the results of our studies on how this project may affect the environment.

We published the Finding of No Significant Impact (FONSI) for the NE 8th Street to SR 520 Improvement Project on September 17, 2008. Below you can download the FONSI in Adobe Acrobat portable document format (pdf).

NE 8th Street to SR 520 Improvement Project FONSI
(pdf 4.96 mb)



*All sections are bookmarked in the provided links below.

Environmental Assessment Chapters 1-4 (pdf 5 mb)
    Environmental Assessment Cover 
    Fact Sheet 
    Title VI Language 
    Table of Contents  
    Chapter 1: Executive Summary 
    Chapter 2: Why do we need this project?  
    Chapter 3: Developing the Alternatives 
    Chapter 4: Description of the Project
Chapter 5, Part 1: The Environment: What's There Now, Project Effects, and Mitigation (pdf 3 mb)
    5.1: Traffic and Transportation 
    5.2: Noise and Vibration Analysis 
    5.3: Communities, Businesses and Public Services 
Chapter 5, Part 2 (pdf 2.6 mb)
    5.4: Visual Quailty
    5.5: Water Resources
    5.6: Ecosystems
Chapters 6-9 (pdf 769 kb)
    Chapter 6: Avoidance and Minimization Measures
    Chapter 7: List of Preparers 
    Chapter 8: Glossary
    Chapter 9: References 

Appendix A (part 1): Agency and Tribal Correspondence (pdf 4 mb)
Appendix A (part 2): Correspondence (pdf 3.4 mb)

Discipline Reports, I-405 NE 8th St. to SR 520 Improvement Project

Air Quality 
Cover; Summary; Sections 1 and 2a; Exhibit 2-3; Exhibit 2-3b; Section 2b-8; Appendix B; Appendix Bi; Appendix Bii

Cultural Resources
Cover; Exhibits 1-5-Project Description; Exhibits 6-8-Methods; Exhibits 9-14; Exhibits 15-17-Glossarya; Glossaryb-Appendix Ai; Appendix Aii-Appendix Bi; Appendix Bii; Appendix Biii; Appendix Biv-Appendix Ci; Appendix Cii-Appendix D

Cumulative Effects Analysis

Economics
Cover; Section 1 and 2a; Exhibit 2-3; Section 2b-8 (Exhibits included)

Ecosystems
Cover; Summary-Section 2a; Exhibit 2-3a; Exhibit 2-3b; Section 2b-4a; Section 4b-Appendix C; Appendix Ci; Appendix Cii; Appendix Ciii; Appendix Civ-Appendix D; Appendix Di; Appendix Dii

Environmental Justice 

Cover; Summary-Section 7; Exhibit 2-3a; Exhibit 3.1-4.1; Exhibit 4.2-5.3; Exhibit 5.4-5.5; Exhibit 5.5; Section 8-Appendix C

Geology, Soils & Groundwater 

Hazardous Materials 
Cover, Discipline Report

Land Use, Patterns, Plans & Policies
Cover-Section 1; Exhibits 2.1-2.3-Section 2a; Exhibit 2-3; Section 2b-4; Section 5-8

Noise and Vibration
Cover; Summary-Section 2a; Exhibit 2-3; Section 2b-Appendix C
 
Section 4 (f) Resources
Cover; Summary-Section 2a; Exhibit 2-3; Section 2b-4a; Section 4b-Appendix A

Traffic and Transportation
Cover; Section 1-2a; Exhibits; Section 2b-Appendix D

Visual Quality
Summary-Appendix B; Appendix Bi; Appendix Bii; Appendix Biii; Appendix Biv; Appendix Bv-Appendix D

Water Resources
Summary-Section 2a; Exhibit 2-3Section 2b-4a; Exhibits 4-2-Section 4b; Exhibit 4-3a; Exhibit 4-3b; Section 4c-Appendix A