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SEPA/NEPA

What is SEPA?

The Washington State Environmental Policy Act (SEPA) provides a way to identify possible environmental impacts that may result from governmental decisions. These decisions may be related to issuing permits for private projects, constructing public facilities, or adopting regulations, policies or plans. Information provided during the SEPA review process helps agency decision-makers, applicants, and the public understand how a proposal will affect the environment. This information can be used to change a proposal to reduce likely impacts. For more information about the SEPA process, visit the Washington State Department of Ecology.

What is NEPA?

The National Environmental Policy Act (NEPA) was enacted by Congress in December of 1969, and signed into law by President Nixon on January 1, 1970. Federal agencies must comply with the NEPA process, which examines the environmental impact of projects resulting from government decisions. The Port of Seattle works with Federal Aviation Administration and Environmental Protection Agency surrounding NEPA decisions. For more information on the NEPA process, visit the Council of Environmental Quality.

Documents

Title Sort ascending Category
2024-01 Sea-Tac Airport (SEA) – Aquatic Mosquito Control Program Threshold Determination of Non-Significance Sea-Tac Airport
2024-01 Sea-Tac Airport (SEA) – Aquatic Mosquito Control Program Environmental Checklist Sea-Tac Airport
2023-02 Sea-Tac Airport (SEA) – PCS Facility Improvements Threshold Determination of Non-Significance Sea-Tac Airport
2023-02 Sea-Tac Airport (SEA) – PCS Facility Improvements Final Determination of Non-Significance Sea-Tac Airport
2023-02 Sea-Tac Airport (SEA) – PCS Facility Improvements Environmental Checklist Sea-Tac Airport
2023-01 Terminal 91 Uplands Redevelopment Final Determination of Non-significance (Final DNS) Maritime
2023-01 Terminal 91 Uplands Redevelopment Environmental Checklist Maritime
2022-02 Sea-Tac Airport (SEA) — Tyee Pond Pipe Replacement: Final Determination of Non-Significance Sea-Tac Airport
2022-02 Sea-Tac Airport (SEA) — Tyee Pond Pipe Replacement Threshold Determination of Non-Significance (DNS) Sea-Tac Airport
2022-01 Sea-Tac Airport (SEA) Snow Storage Expansion: Final Mitigated Determination of Non-Significance Sea-Tac Airport
2022-01 Sea-Tac Airport (SEA) – Snow Storage Expansion: Modified Final Mitigated Determination of Non-Significance Sea-Tac Airport
2022-01 Sea-Tac Airport (SEA) – Snow Storage Expansion: Environmental Checklist Sea-Tac Airport
2021-09 Harbor Island Marina Dock E Floats and North Pier Improvements FINAL DNS Maritime
2021-08 SEPA Final DNS for Terminal 30 Central Substation Replacement Project Maritime
2021-08 SEPA DRAFT DNS for Terminal 30 Central Substation Replacement Project Maritime
2021-08 SEPA Checklist for Terminal 30 Central Substation Replacement Project Maritime
2021-07 Charting the Course to Zero: Port of Seattle’s Maritime Climate and Air Action Plan Environmental Checklist Maritime
2021-06 Terminal 91 Berths 6 & 8 Redevelopment Project FINAL Determination of Non-Significance (DNS) Maritime
2021-06 Pier 66 Shore Power Threshold DNS Final Maritime
2021-05 Pier 66 Shore Power Project Environmental Checklist and Attachments Maritime
2021-05 Pier 66 Shore Power Project DNS Threshold Determination Maritime
2021-04 Sea-Tac Airport (SEA) – Widen Arrivals Drive: Enviornmental Checklist Sea-Tac Airport
2021-03 Sea-Tac Airport – Widen Arrivals: Final Determination of Non-Significance Sea-Tac Airport
2021-03 Sea-Tac Airport - North Runway Protection Zone Emergency Access Culvert Replacement Environmental Checklist Sea-Tac Airport
2021-02 Northwest Ports Clean Air Strategy Environmental Checklist Maritime
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