Latest information on the Lower Duwamish

Ecology, EPA, King County, and the City of Seattle work continuously to    control sources of contamination to the Lower Duwamish Waterway (LDW). We post the latest source control information on this page, including reports and updates on work underway. 

Super-sack spill at Lafarge

On September 19, we received notification of a contaminated soil release into the Duwamish River at the Lafarge facility located at 5400 West Marginal Way in Seattle. The release occurred as a super-sack of contaminated soil ripped open while being transferred from a barge to the shore facility. The sack that ripped open had approximately 21,300 pounds of soil, and roughly 4,020 pounds of that soil volume fell into the Duwamish River when the sack failed.
The contaminated soil came from an environmental cleanup at the Yakutat Air Base in Alaska, and the generator was the US Army Corps of Engineers. The bagged soils were barged to the Lafarge Seattle facility to transfer the soil into rail cars destined for the Columbia Ridge Disposal Facility in Oregon. According to the waste disposal profile, the waste did not designate as a federal Resource Conservation and Recovery Act (RCRA) hazardous waste, or state dangerous waste, and it did not carry any assigned waste codes.
Lafarge hired a vacuum truck company to recover the spilled soil from the barge and the shore-side dock. In response to Ecology directives, Lafarge also hired a diving company to remove the soil from the Duwamish River to the extent practicable. Contractors were able to recover approximately 4,000 pounds of soil from the river bottom. The staff at the facility cleaned up approximately 10,380 pounds of soil by vactor truck, 5,900 pounds of soil on barge by labor and 1,000 lbs of soil on deck by labor. Lafarge is conducting a thorough review of transloading procedures and updating their best management practices (BMPs) for future barge-to-shore transfer activities. 

West of 4th cleanup site pilot study begins this week

From October 8- 12, we oversaw a pilot study in S. Fidalgo St. as part of the West of 4th site cleanup. The study is located west of East Marginal Way S, a little over 300 hundred feet away from the east bank of the Waterway. If you were in this area, you might've seen a truck and drilling equipment injecting the treatment chemicals. One lane of Fidalgo St., near the injection locations, was closed during this work.

Cleanup chemicals were injected into groundwater contaminated with trichloroethene (TCE) and vinyl chloride at numerous points along a north-to-south line. The cleanup chemicals included a chemical reducing agent (containing iron) and a biodegradation enhancement (to help the natural processes in groundwater reduce the chemical concentrations). Groundwater treatment occurred below ground, and no groundwater was pumped to the surface.  

During the weeks following the treatment, monitoring wells will be sampled. After the initial weekly sampling, the wells will be sampled monthly, then quarterly for at least six months. We will review the results to determine if this method is working. If effective, it will be considered a cleanup option and more fully evaluated in the Feasibility Study.

Industrial Stormwater General Permit reissuance process begins with public listening sessions

The current Industrial Stormwater General Permit expires on Dec. 31, 2019. We are beginning the reissuance process with a series of public listening sessions to discuss potential changes to the permit. These meetings are a chance for you to learn more about the proposed changes to the permit and to ask Ecology staff any questions about permit coverage. Our proposed changes to the permit include:

  • Adding two new industry groups that require coverage
  • Adding language to protect groundwater
  • Changing the timing of First Flush
  • Revising requirements for Consistent Attainment

Join us at an in-person listening session on October 16, 2018, at 6 p.m at the Renton Community Center, 1715 Maple Valley Hwy, Renton, WA. You can also download a previously recorded webinar version.

Visit Ecology’s webpage for more information. We will answer questions and accept informal feedback on the proposed changes until Nov. 26, 2018.

State Supreme Court issues decision on Seattle Iron & Metals permit appeal

On August 30, the Washington State Supreme Court issued their decision on the Puget Soundkeeper Alliance appeal of the NPDES permit issued to Seattle Iron & Metals in 2013. The court ruled in favor of Ecology. The elements of this case are technical. It deals with the analytical methods used by laboratories to quantify how many PCBs are in a sample of water, and which method is legally required to be used to compare the amount of PCBs in discharges to the limits set in the permit.
The decision gives us certainty in our regulatory efforts by using a proven and consistent testing method. We will continue developing and issuing permits in accordance with this decision and best available science. With this decision, we will move forward and issue a new permit to Seattle Iron & Metals that incorporates improvements made on the site and follows our latest permitting guidance to increase protection of the Duwamish River. We expect to provide an update at the Nov. 7, 2018 Lower Duwamish Waterway stakeholder meeting.


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