Superfund Information Systems: Site Profile

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Health & Environment

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What Are the Risks at the Site?

The greatest health risk to people is by ingesting contaminated resident fish and seafood. Unfortunately, the river has harmful chemicals, such as PCBs, that can cause health problems in humans. You cannot see these chemicals in the fish. They get into fish, shellfish and crab that spend their entire lives in the river (“resident fish”). The Washington State Department of Health recommends salmon as the healthiest choice to eat because they spend a short time in the river. There is also risk by coming into direct contact with contaminated sediment.

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Contaminant Information

There are many chemical contaminants in LDW sediment, fish and shellfish. Most of the human health risk comes from polychlorinated biphenyls (PCBs), arsenic, carcinogenic polycyclic aromatic hydrocarbons (cPAHs), as well as dioxins and furans.

PCBs (polychlorinated biphenyls) are human-made chemicals (for example, used in electrical equipment, transformers, caulk and paint) banned from use in most applications in 1979, PCBs stay in the environment for a long time and can build up in fish and shellfish. PCBs may cause cancer in people who have been exposed over a long time. They can also affect learning abilities in children. PCBs are linked to other adverse health effects such as low birth weight, thyroid disease, and immune system disorders.

Arsenic is naturally present at low levels in Puget Sound area rock and soil. Industrial activities have spread additional arsenic over much of the Puget Sound region. Long-term exposure to toxic forms of arsenic may cause skin, bladder, and other cancers.

CPAHs (carcinogenic polycyclic aromatic hydrocarbons) are formed during the burning of substances such as coal, oil, gas, wood, garbage, and tobacco. Long periods of breathing, eating, or skin contact with high levels of some cPAHs may increase a person’s risk of cancer.

Dioxins and furans are by-products of burning, chemical manufacturing, and metal processing. Dioxins last a long time and can build up in fish and shellfish. Toxic effects related to dioxins include reproductive problems, problems in fetal development or in early childhood, immune system damage, and cancer.

View a full list of contaminants of concern for this site.

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

See EPA's mapping database for environmental information about the Duwamish area.

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Performance Measures

EPA uses performance measures to track environmental results at Superfund sites. If you have any questions or concerns about the measures at this site, please contact the site team members listed under Site Contacts.

Read more about Superfund Remedial Performance Measures.

Status at this
Superfund Site
What does this mean?
Human Exposure Under Control No Yes means assessments indicate that across the entire site:
  1. There are currently no unacceptable human exposure pathways; and
  2. EPA has determined the site is under control for human exposure.

No means an unsafe level of contamination has been detected at the site and a reasonable expectation exists that people could be exposed.

Insufficient data means that, due to uncertainty regarding exposures, one cannot draw conclusions as to whether human exposures are controlled, typically because:
  1. Response to the contamination has not begun; or
  2. The response has begun, but it has not yet generated information sufficiently reliable to evaluate whether there are currently any unacceptable human exposure pathways at the site.
Groundwater Migration Under Control No

Yes means EPA reviewed all information on known and reasonably expected groundwater contamination. EPA concluded the migration of contaminated groundwater is stabilized and there is no unacceptable discharge to surface water. EPA will conduct monitoring to confirm that affected groundwater remains in the original area of contamination.

No means EPA has reviewed all information on known and reasonably expected groundwater contamination, and the migration of contaminated groundwater is not stabilized.

Insufficient data means that due to uncertainty regarding contaminated groundwater migration, EPA cannot draw conclusions as to whether the migration of contaminated groundwater is stabilized.

Construction Complete No

Yes means the physical construction of the cleanup is complete for the entire site.

No means either physical construction is not complete or actions are still needed to address contamination.

Sitewide Ready for Anticipated Use No Yes means:
  1. All cleanup goals affecting current and reasonably anticipated future land uses of the entire site have been achieved, so there are no unacceptable risks;
  2. All required land-use restrictions or other controls have been put in place; and
  3. The site has achieved Construction Complete status.

No means that one or more of these three criteria have not been met. However, a site listed as no may still have redevelopment occurring on portions of the site and may be eligible for additional redevelopment.

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