Lower Duwamish Waterway
Ecology, the City of Seattle, King County and the EPA work
continuously on source control. Ecology posts the latest source control
information on this page, including reports and updates on work
Ecology partners with zoo to study PCBs in river otter scat,
and you can help!
Ecology provided funding to Michelle Wainstein, a researcher at Woodland
Park Zoo, to analyze PCBs in river otter scat (poop). Her team collected
samples from West Seattle, Duwamish River, Des Moines, east of Auburn,
and Black Diamond. They found higher levels of PCBs in samples collected
from the Duwamish, and lower levels in samples from upstream areas.
the final report here.
The North American River Otter can serve as an indicator of the
Green-Duwamish River’s health. Studying the otter population and the
toxins in their scat can help us understand how contamination moves
through the ecosystem. In fact, the Duwamish cleanup plan specifically
includes a cleanup level for PCBs to protect river otters.
If you’d like to help with this research,
sign up with the Zoo to be an “Otter Spotter”! Anyone can
participate by recording observations of otters and their behavior along
the length of the Green-Duwamish River.
Duwamish River Long-term Stewardship: Request for Proposals
The Elliott Bay/Duwamish River Restoration Program is a program
that oversees a natural resource damage settlement with the City of
Seattle and King County. They are seeking a stewardship partner to
provide habitat stewardship services for four habitat restoration sites
on the Duwamish River near Seattle, Washington. Funding is available for
regular inspections, maintenance activities, qualitative monitoring,
adaptive management activities and community involvement on these
Duwamish restoration sites.
The first phase in the process is a request for information from
interested parties to see if they are eligible for funding. During the
second phase, eligible parties submit detailed proposals. The
eligibility information and proposals will be reviewed by the program
members including NOAA, US Fish and Wildlife Service, Ecology,
Muckleshoot Tribe, the Suquamish Tribe, City of Seattle, and King
The request for proposals is available here:
The deadline for submissions of answers to Phase One eligibility
questions is Thursday, July 6, 2017. For more information, please
For more information about Natural Resource Damage Assessment and
Restoration in Washington, visit our website at:
New groundwater pilot studies to begin for
Burlington-Environmental Georgetown site*
Starting in May, contractors working for Stericycle will study methods
that would enhance the breakdown of 1,4 dioxane found in groundwater
under Georgetown (east of 4th Ave). The studies will test two different
below ground cleanup methods. The studies will be done along 6th Avenue
South and near the intersection of Maynard Avenue South and South Lucile
Questions? Contact Ed Jones,
Ecology’s PSC-Georgetown site manager, with questions about these
studies or other aspects of the cleanup. Email him at
email@example.com, or call
Learn more at
website and check out our handouts available in
Spanish (en español), and
*Burlington Environmental LLC, a wholly owned subsidiary of PSC
Environmental Services, LLC (PSC), which is a wholly owned subsidiary of
Stericycle Environmental Solutions, Inc. (Stericycle).
Ecology is sampling groundwater on cleanup sites for low
levels of PCBs
Ecology’s Toxic Cleanup Program sampled groundwater and surface water
for polychlorinated biphenyls (PCBs) at 14 cleanup sites in March. This
is part of the larger
Green-Duwamish River Watershed PCB Congener Study, to determine what
types of PCBs are found and where.
In this study, we are using a method that can detect PCB congeners
(specific PCB molecules) at very low levels. Previous analytical methods
could not measure low enough concentrations to determine if groundwater
meets water quality standards.
For more information, see the
Sampling Analysis Plan (SAP) and Quality Assurance Project Plan (QAPP).
Green-Duwamish Pollutant Loading Assessment meeting for
interested parties was held March 15, 2017
For more information on the Pollutant Loading Assessment, visit
Seattle metal recycler fined $64,000 for pollution discharges
to Duwamish River
fined Seattle Iron and Metals Corporation $64,000 for discharging
stormwater with excessive levels of several pollutants into the Duwamish
River. The company’s monitoring records showed 27 violations of
pollutant limits from February 2015 through December 2016. On June 20
and 21, 2016, stormwater was allowed to bypass the treatment system,
which resulted in four additional violations. Seattle Iron and Metals
Corporation also failed to submit monitoring reports for the fourth
quarter in 2015. The company paid the fine.
Ecology’s water quality penalties go to the state’s
Coastal Protection Fund which issues grants to public agencies and
tribes for water quality restoration projects.
Site Work begins for the Georgetown Wet Weather Treatment
King County is beginning site demolition and soil remediation work at
the home of the future Georgetown Wet Weather Treatment Station. The
station will treat combined sewage and stormwater flows from the
Michigan and Brandon combined sewer overflow basins. Ecology’s Water
Quality Program reviewed the plans for this project to ensure that it
meets the state’s water quality laws. Ecology is reviewing the 90%
design documents for the treatment facility, conveyance system
improvements, and the facility’s outfall in the Duwamish River (where
treated wastewater will discharge). King County’s project website:
City of Seattle has begun testing stormwater treatment
technologies at Riverside Drive as part of the
South Park Water Quality project.
This stormwater treatment facility will treat runoff from the 7th Avenue
storm drain basin in South Park. The project is part of Seattle’s
Plan to protect Seattle’s waterways, approved by Ecology and EPA,
which addresses control of
sewer overflows (CSOs)
and includes stormwater projects.
2017 Lower Duwamish Cleanup Sites Update
Ecology is mailing an
cleanup sites managed by our Toxics Cleanup Program in the LDW. It explains
the status of each site and how these cleanups fit into Ecology’s Source Control
Strategy. If you would like to receive a paper copy of such mailings in the
future, contact Amy White at 425-649-7052 or
Save the Date: March 15, 2017 is the next Green-Duwamish Pollutant
Loading Assessment meeting for interested parties
Tukwila Community Center Banquet Hall, 12424 42nd Avenue South, Tukwila
- When: 1pm to 4pm.
- What: Update on the status of watershed model set-up and results from the PCB Congener
Assessment Phase 2.
For more information on the Pollutant Loading Assessment, visit
Waste Management’s Duwamish Reload facility is ready to accept
Waste Management (WM) has all necessary permits to transfer
contaminated soils and sediments from trucks and barges to railcars on the
property known as the Crowley 8th Avenue Cleanup Site. WM has been accepting
contaminated soils since October. They plan to load contaminated dredged
sediments from barges to the facility in early 2017. Ecology and other local
regulatory agencies will continue to inspect the facility regularly for
Byproduct PCBs Study
In November, Ecology released the second of three planned studies looking at the
presence of byproduct PCBs in common consumer products, such as paper and
packaging. The study looked for detectable levels of PCBs in 201 products. Read
full report, or download the
PCBs in Sampling Equipment
Ecology has posted a
memo about the potential for PCB contamination from sampling equipment
tubing materials. This factor should be considered when planning to conduct
laboratory analyses using Method 1668 (for low-level PCB congener analyses).
Carbon Amendment Pilot Study
The Lower Duwamish Waterway Group (LDWG) is conducting an Enhanced Natural
Recovery (ENR) Activated Carbon pilot study. Construction started on November
28, 2016 and is expected to complete in January 2017.
ENR means covering contaminated sediments (river mud) with a thin layer of
sand to speed up the process of natural recovery – the natural deposition of
cleaner sediments to cover contaminated sediments. The goal of the pilot study
is to determine whether adding activated carbon to the sand layer can reduce PCB
bioavailability in sediment as part of ENR. PCB bioavailability is the amount of
PCBs that can be taken up by fish and other living things in the river.
Monitoring will continue for three years following construction. For more
information, see the
Assurance Project Plan.
Phase 3 Begins for USGS Green River Loading Study
The purpose of this research project is to find out how much suspended
sediment and chemical pollution is coming down the river into the cleanup
site. Phase 1 and 2 seem to show that the sediments coming downstream have
lower levels of PCBs than previous estimates, and there is less total
material coming down than other previous estimates. The
Quality Assurance Project Plan (QAPP) has been approved. USGS will
continue collection of water and suspended sediment samples at River Mile
10.8 (Foster Golf Links) until April 2017. Additionally in this phase, they
will analyze the samples to estimate the concentration of PCBs dissolved in
Whitehead Tyee Agreed Order Signed
In August 2016, Ecology entered into a legal agreement called
an Agreed Order (AO) with Seattle Iron & Metals Corporation and 730
Myrtle LLC (the Potentially Liable Parties or PLPs) for the site located
at 730 South Myrtle Street in the Georgetown area of Seattle. Click here
to view the web page for the
Whitehead Tyee Cleanup Site.
Phase I Municipal Stormwater Permit Modified
Ecology’s modification to the
Phase I Municipal Stormwater Permit took effect in August 2016. It
includes requirements for Seattle to adaptively manage their municipal
stormwater discharges to the Lower Duwamish Waterway.
Ecology Updates Source Control Strategy
Ecology made significant updates to their
Strategy for the Lower Duwamish Waterway, which include developing a
procedure to let EPA know when source control is sufficient for river
cleanup to begin, and requesting Source Control Implementation Plans
from other local regulatory agencies.
City of Seattle Publishes Draft Final Source Control
Draft Final Source Control Implementation Plan describes their
planned activities to control sources within their authorities over a
five year period (2015-2020).
See their website for the Plan,
Appendices, and Map Atlas, along with a video that highlights their
source control activities.
Progress Report: USGS Green River Loading Study
The U.S. Geological Survey submitted a
Progress Report and
Tables to document the status of the project, which was suspended in autumn 2015 due to a
Green-Duwamish River Watershed PCB Congener Study: Phase 1
Ecology published a
summary of available information on PCB congeners and Aroclors,
dated April 27, 2016. The report identifies important issues to consider
when evaluating historical PCB congener and/or Aroclor data or when
collecting new data.
Technical Memo on Groundwater Cleanup Levels
Ecology produced a
technical memorandum, revised March 1, 2016, for establishing
groundwater cleanup levels for upland sites along the Lower Duwamish
Phase 2 Report: USGS Green River Loading Study
Between November 2013 and March 2015, the U.S. Geological
Survey collected representative samples of water, suspended sediment, or
bed sediment from the Duwamish River upstream of the Superfund site.
Samples were analyzed for a large suite of compounds, including metals,
dioxins/furans, polycyclic aromatic hydrocarbons, pesticides,
polychlorinated biphenyl (PCB) Aroclors and the 209 PCB congeners, and
other chemicals. For more information see the
2 Report and its
Phase 1 Report: USGS Green River Loading Study
Between February and June 2013, the U.S. Geological Survey collected
representative samples of whole water, suspended sediment, and (or) bed
sediment from a single strategically located site on the Duwamish River,
during seven periods of different flow conditions. For more information, see
Phase 1 Report.
Stakeholders' Meeting Presentations: