Map of "Early Action" cleanup areas.
Timeline of key milestones in the Superfund cleanup process (click on image for larger view).
Next steps in the cleanup process following the Record of Decision (click on image for larger view).
Site History: The Lower Duwamish Waterway Superfund Site is a 5.5 mile stretch of the Duwamish River that flows into Elliott Bay in Seattle, Washington. The waterway is flanked by industrial corridors, as well as the South Park and Georgetown neighborhoods. The site was added to EPA's National Priorities List in 2001.
A century of heavy industrial use has left the waterway contaminated with toxic chemicals from many sources – industries along its banks, stormwater pipes, and runoff from upland activities, streets and roads. Pollution in the river sediments includes polychlorinated biphenyls (PCBs), dioxins/furans, carcinogenic polycyclic aromatic hydrocarbons (cPAHs), and arsenic. Many of these chemicals stay in the environment for a long time, and have built up to unsafe levels in resident fish and shellfish. Because of contamination, state and local health departments warn against eating crab, shellfish, or bottom-feeding fish from the Lower Duwamish River (salmon are ok because they move quickly through the waterway).
EPA and the Washington Department of Ecology are working to clean up contaminated sediment and control sources of additional contamination in the waterway.
Feasibility Study Update
Draft Feasibility Study (cleanup alternatives) available: The draft Feasibility Study 
is available for review. The study, developed by the Lower Duwamish Waterway Group, looks at a range of alternatives to clean up the waterway, how the alternatives work, and the pros and cons of various combinations of cleanup methods, including costs and construction timelines.
EPA and Ecology received public comments on the draft cleanup alternatives through January 14, 2011. Those comments are being considered in developing the final Feasibility Study. The Feasibility Study will be part of the Administrative Record and available for public review along with EPA and Ecology’s recommendation for the cleanup. That recommendation is called the Proposed Plan and will be available for public comment in 2012.
"Early Action" Cleanup Areas
Early Action cleanup areas are parts of a Superfund site that may become a threat to people or the environment before the long-term cleanup is completed. The following areas within the Lower Duwamish Superfund Site have already begun or completed cleanup activities.
- Slip 4 - Sediment cleanup project to remove PCB-contaminated sediments from about 4 acres of the waterway near the Boeing Plant 2 site.
- Terminal 117 - Sediment and upland cleanup project to remove PCB contamination from the site of the former Duwamish Manufacturing and Malarkey Asphalt Company, in the South Park neighborhood.
- Boeing Plant 2 - Sediment and upland cleanup project at former Boeing airplane manufacturing facility.
- Jorgensen Forge - Sediment and upland cleanup project at site of several former steel-related industrial operations. This site is jointly managed by EPA and Ecology.
- Duwamish Diagonal - Sediment cleanup project just upstream from Harbor Island, completed in 2005 by King County's Sediment Management Program.
- Norfolk CSO - Sediment cleanup project around the Norfolk Combined Sewer Overflow (CSO) near the south end of Boeing Field. The site is being managed by King County's Sediment Management Program.
Who Pays for the Cleanup?
EPA's policy is to have the polluters pay for cleaning up pollution they created. Since pollution has been entering the Duwamish River for over 100 years from many different sources, it can be difficult to determine who is responsible for paying for the cleanup.
Lower Duwamish Waterway Group - In the interim, four organizations have stepped forward to pay for the Remedial Investigation and Feasibility Study: City of Seattle, King County, Port of Seattle, and the Boeing Company, collectively known as the Lower Duwamish Waterway Group
Information Collection Requests - To help us learn more about known or suspected releases of contamination, we're continuing to send Superfund Information Collection Requests (also called "CERCLA 104e letters") to current and former property owners near the site.