EPA Reaches $668M Settlement Agreement For Continued Cleanup Of Lower Duwamish Waterway Superfund Site In Seattle Area

Today, the U.S. Environmental Protection Agency, U.S. Department of Justice, and the state of Washington reached agreement on a proposed settlement with more than 100 potentially responsible parties to address hazardous substances released into the Lower Duwamish Waterway in Seattle. Cleanup work is estimated to cost $668M and take at least 10 years to complete.

Under the settlement, the Lower Duwamish Waterway Group—which consists of the Boeing Company, city of Seattle, and King County—agreed to design and perform the cleanup plan EPA selected for the in-water portion of the Lower Duwamish Waterway Superfund site.

The cleanup plan requires Boeing, Seattle, and King County to conduct dredging and capping and take other measures to clean up the most contaminated parts of the Waterway. To help fund the required work, the Lower Duwamish Waterway Group will receive about $130M from other responsible parties and about $140M from federal agencies.

“This settlement finally ensures full-scale cleanup of the Lower Duwamish Waterway,” said EPA Office of Enforcement and Compliance Assurance Assistant Administrator Jeffrey A. Hall. “The cost-sharing agreement resulting from negotiations among many parties shows that this Administration will make good on its promise to expedite cleanup of hazardous pollutants while ensuring responsible parties are held accountable and the public is not left with the bill for the cleanup.”

“This settlement demonstrates EPA’s commitment to protecting public health, cleaning up contaminated sites, and advancing cooperative federalism with our state partners,” said EPA Region 10 Administrator Emma Pokon. “Cleaning up this waterway will enhance residents’ use, support safer fishing, protect wildlife, and foster a vibrant industrial core in the heart of Seattle.”

“The Duwamish is a vital asset to Seattle and the surrounding community. By lodging this settlement with the court today and seeking public comment, we take a big step toward restoring the Lower Duwamish,” said Acting Deputy Assistant Attorney General Justin Heminger of the Justice Department’s Environment and Natural Resources Division. “We are proud to play an integral role in negotiating with more than one hundred other parties to achieve this milestone agreement.”

“Ecology has worked with our cleanup partners and the community for many years to control and reduce the pollution entering the Lower Duwamish Waterway. Settling the question of who will pay for the work is critical, especially now that the final stages of active cleanup have begun,” said Washington State Department of Ecology Director Casey Sixkiller. “This is a crucial step toward achieving the community’s vision of a clean river for the people and wildlife living in the Lower Duwamish watershed.”

The Lower Duwamish Waterway Superfund site is a five-mile segment of Seattle’s only river, the Duwamish. The Waterway has served as Seattle’s major industrial corridor since the early 1900s, hosting industries such as airplane manufacturing, timber operations, steel mills, and chemical production. Discharges from these industries, and sewage and stormwater systems, contributed to sediment contamination within the waterway.

EPA identified 41 hazardous substances in sediments that pose significant risks to human health and the environment in the Waterway; These include polychlorinated biphenyls (PCBs), arsenic, carcinogenic polycyclic aromatic hydrocarbons, dioxins, and furans.

The settlement is authorized under the Comprehensive Environmental Response, Compensation, and Liability Act (commonly known as Superfund) and Washington State’s Model Toxics Control Act for releases of hazardous substances.

The consent decree was lodged in U.S. District Court for the Western District of Washington, is subject to a 30-day public comment period, and final court approval. The lodged consent decree and information on submitting public comment is available on the DOJ Proposed Consent Decrees webpage.

For more information, visit Lower Duwamish Waterway Superfund Settlement Summary webpage.

For more information, visit EPA’s Lower Duwamish Waterway Superfund site website, and the Lower Duwamish Waterway Group’s webpage.