Lower Duwamish Waterway Superfund Site | Region 10 | US EPA

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Lower Duwamish Waterway Superfund Site

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Julie Congdon (congdon.julie@epa.gov)

Contacto en Espaņol:
Michael Ortiz (ortiz.michael@epa.gov)

Community Advisory Group:
Duwamish River Cleanup Coalition Exit EPA Disclaimer

Lead State Agency:
Dept. of Ecology's Lower Duwamish Cleanup Program Exit EPA Disclaimer

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Fishers Study

The final report for the Lower Duwamish Waterway Fishers Study is available. The study collected information about fishing on the Duwamish River. Based on the results, Public Health Seattle-King County (PHSKC) will establish a community-based Healthy Seafood Consumption "Institutional Control" Program for the LDW Superfund Site, overseen by EPA.

For more information about the Fishers Study and the next steps, please contact:

  • EPA: Rebecca Chu (chu.rebecca@epa.gov), 206-553-1774
  • PHSKC: Sinang Lee (sinang.lee@kingcounty.gov), 206-263-1192

Read the report:

Fact sheet:

Final Cleanup Plan (Record of Decision)

The Record of Decision - or "ROD" - is the EPA’s cleanup plan to reduce risks to people’s health and the environment from toxic chemicals in the river.

The plan includes details of the cleanup of about 177 acres in the waterway. Cleanup will involve dredging, capping, and natural sedimentation. The cleanup will cost an estimated $342 million.

These cleanup actions complement the work of state, county and city agencies to improve the health of the Green/Duwamish watershed. All of these actions together will remove over 90 percent of contamination in the waterway.

GIS Mapping Data - GIS mapping data files for the selected remedy are available by request. Contact Julie Congdon (congdon.julie@epa.gov) at 206-553-2752 if you are interested in using these files.

Fact Sheets:

"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 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 was completed in 2012.
  • 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.
State/Local Cleanup Work
Who Pays for the Cleanup?

The 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 should pay 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 Exit EPA Disclaimer

General Notice Letters - General notice letters inform recipients that they are identified as "potentially responsible parties" at Superfund sites, that they may be liable for cleanup costs at the site, and explain the process for negotiating the cleanup with the EPA.

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.

Site History

The Lower Duwamish Waterway Superfund Site is a 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 (NPL) 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).

The EPA and the Washington Department of Ecology are working to clean up contaminated sediment and control sources of additional contamination in the waterway.

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