Environmental Manual M 31‑11.25 September 2021 Engineering and Regional Operations Development Division, Environmental Services Office Americans with Disabilities Act (ADA) Information: This material can be made available in an alternate format by emailing the Office of Equal Opportunity at [email protected] or by calling toll free, 855-362-4ADA(4232). Persons who are deaf or hard of hearing may make a request by calling the Washington State Relay at 711. Title VI Notice to Public: It is the Washington State Department of Transportation’s (WSDOT) policy to assure that no person shall, on the grounds of race, color, or national origin, as provided by Title VI of the Civil Rights Act of 1964, be excluded from participation in, be denied the benefits of, or be otherwise discriminated against under any of its programs and activities. Any person who believes his/her Title VI protection has been violated, may file a complaint with WSDOT’s Office of Equal Opportunity (OEO). 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Contents Chapter 100 Purpose and Overview . 100-1 Chapter 200 Environmental considerations in transportation planning . 200-1 200.01 Introduction and overview ........................................200-1 200.02 Environmental considerations in transportation planning ..............200-1 200.03 Right-sizing .....................................................200-2 200.04 Federal Planning and Environmental Linkages (PEL) studies............200-4 Chapter 300 Project scoping and programming . 300-1 300.01 Introduction.....................................................300-1 300.02 Project scoping ..................................................300-2 300.03 Project types with special requirements.............................300-4 300.04 Project classification..............................................300-9 300.05 NEPA classifications ..............................................300-9 300.06 SEPA classifications .............................................300-10 300.07 Revision of project scope and classification .........................300-11 300.08 Highways Over National Forest Lands .............................300-11 300.09 Environmental database resources ................................300-12 300.10 Applicable statutes and regulations................................300-13 300.11 Abbreviations and acronyms......................................300-13 300.12 Glossary .......................................................300-14 Chapter 400 Environmental review (NEPA/SEPA) and transportation decision making . 400-1 400.01 Environmental review in project development .......................400-1 400.02 Roles and responsibilities .........................................400-3 400.03 Identifying the type of environmental document ....................400-10 400.04 NEPA/SEPA procedures .........................................400-10 400.05 Ensuring environmental document quality..........................400-12 400.06 Using existing environmental documents...........................400-13 400.07 Documenting an Environmental Impact Statement (EIS) ..............400-17 400.08 Documenting an Environmental Assessment (EA) ...................400-24 400.09 Categorical Exclusions/Exemptions (CEs)...........................400-25 400.10 Environmental document legal considerations ......................400-26 400.11 Applicable statutes and regulations................................400-29 400.12 Abbreviations and acronyms......................................400-30 400.13 Glossary .......................................................400-31 WSDOT Environmental Manual M 31-11.25 Page 5 September 2021 Contents Chapter 412 Indirect and cumulative impacts . 412-1 412.01 Introduction.....................................................412-1 412.02 Applicable statutes, regulations, & executive orders ..................412-3 412.03 Considerations during project development .........................412-3 412.04 Analysis & documentation requirements ............................412-4 412.05 External engagement .............................................412-9 412.06 Internal Roles and responsibilities ..................................412-9 412.07 Mitigation.......................................................412-9 412.08 Applicable permits & approval process ..............................412-9 412.09 Abbreviations and acronyms.......................................412-9 412.10 Glossary ........................................................412-9 Chapter 420 Earth (Geology and Soils) . 420-1 420.01 Introduction.....................................................420-1 420.02 Applicable statutes, regulations, executive orders, & agreements .......420-2 420.03 Considerations during project development .........................420-2 420.04 Analysis & documentation requirements ............................420-3 420.05 External engagement .............................................420-4 420.06 Internal roles and responsibilities...................................420-4 420.07 Applicable permits & approval process ..............................420-5 420.08 Mitigation.......................................................420-5 420.09 Abbreviations and acronyms.......................................420-6 420.10 Glossary ........................................................420-6 Chapter 425 Air Quality, Greenhouse Gases, Energy . 425-1 425.01 Introduction.....................................................425-1 425.02 Applicable statutes, regulations, executive orders, & agreements .......425-2 425.03 Considerations during project development .........................425-3 425.04 Analysis & documentation requirements ............................425-3 425.05 External engagement .............................................425-9 425.06 Internal roles and responsibilities..................................425-10 425.07 Applicable permits & approval process .............................425-10 425.08 Mitigation......................................................425-10 425.09 Abbreviations and acronyms......................................425-11 425.10 Glossary .......................................................425-12 425.11 Exhibit.........................................................425-14 Page 6 WSDOT Environmental Manual M 31-11.25 September 2021 Contents Chapter 430 Stormwater and Water quality . 430-1 430.01 Introduction.....................................................430-1 430.02 Applicable statutes, regulations, executive orders, & agreements .......430-1 430.03 Surface water quality considerations during project development ......430-4 430.04 Analysis & documentation requirements ............................430-8 430.05 External engagement ............................................430-10 430.06 Internal roles and responsibilities..................................430-10 430.07 Applicable permits & approval process .............................430-12 430.08 Mitigation......................................................430-13 430.09 Abbreviations and acronyms......................................430-13 430.10 Glossary .......................................................430-15 Chapter 431 Wetlands . 431-1 431.01 Introduction.....................................................431-1 431.02 Applicable statutes, regulations, executive orders, & agreements .......431-2 431.03 Considerations during project development .........................431-2 431.04 Analysis & documentation requirements ............................431-7 431.05 External engagement .............................................431-8 431.06 Internal roles and responsibilities...................................431-8 431.07 Applicable permits & approval process .............................431-10 431.08 Mitigation......................................................431-12 431.09 Abbreviations and Acronyms .....................................431-16 431.10 Glossary .......................................................431-16 431.11 Exhibits........................................................431-19 Chapter 432 Special Flood Hazard Area . 432-1 432.01 Introduction.....................................................432-1 432.02 Applicable statutes, regulations, executive orders, & agreements .......432-2 432.03 Considerations during project development .........................432-3 432.04 Analysis & documentation requirements ............................432-5 432.05 External engagement .............................................432-6 432.06 Internal roles and responsibilities...................................432-6 432.07 Applicable permits & approval process ..............................432-7 432.08 Mitigation.......................................................432-7 432.09 Abbreviations and acronyms.......................................432-8 432.10 Glossary ........................................................432-8 432.11 Exhibits........................................................432-11 WSDOT Environmental Manual M 31-11.25 Page 7 September 2021 Contents Chapter 433 Groundwater . 433-1 433.01 Summary of Requirements for Groundwater .........................433-1 433.02 Groundwater Policy Guidance .....................................433-2 433.03 Groundwater Related Interagency Agreements.......................433-2 433.04 Applicable Statutes and Regulations ................................433-3