Department of Ecology News Release - June 14, 2019

Soil cleanup planned for Duwamish shoreline site

Owner also agrees to cleanup process for entire property

The Snopac site is located next to Slip 1, an inlet of the Duwamish Waterway.

The owner of an industrial property along the Duwamish Waterway in Seattle has negotiated an agreement with the Washington Department of Ecology to clean a portion of the site and test all of it for soil and groundwater contamination, a step toward planning a future final cleanup.
Ecology invites the public to review and comment on the agreement, called an agreed order, and the cleanup plan, called an interim action, through July 9, 2019. A draft public participation plan, which describes how Ecology will inform people about the cleanup process, is also available for review. (All document links are PDF files.)
The order, interim action work plan and public participation plan cover the 1.3 acre Snopac Property at 5055 East Marginal Way S. Under the order, 5055 Properties LLC will investigate and report on contamination at the site, study cleanup alternatives, and propose a cleanup action plan. The interim action plan covers the removal of contaminated soil adjacent to a warehouse the owners plan to demolish.  

History and contamination

Various businesses have occupied the site since 1935, including a towing company that operated underground storage tanks for 30 years. A shipbuilding and repair company disposed of sandblast grit, using the material as fill on part of the property. The site has been vacant since 2008.
Soil samples show concentrations of metals, carcinogenic polycyclic aromatic hydrocarbons (cPAHs), and polychlorinated biphenyls (PCBs). Groundwater samples contain metals, and waterway sediments near the site contain metals, PAHs and PCBs. All of these contaminants are toxic.

 Part of the Lower Duwamish Waterway cleanup

The cleanup will contribute to a larger effort to control sources of contamination in Lower Duwamish Waterway sediments. Ecology and the U.S. Environmental Protection Agency (EPA) jointly manage the Lower Duwamish Waterway cleanup, along the approximately 5 miles of waterway upstream from Harbor Island. 
Ecology oversees a variety of efforts to control sources of pollution that could re-contaminate waterway sediments after cleanup. This source control work includes cleanups at contaminated sites along or near the Duwamish. The agreed order and interim action for the Snopac property adds this site to a list that includes 21 other formal Ecology cleanup sites along or near the Duwamish Waterway as well as five sites managed by EPA.

 Cleanup and commenting information

Information about the site’s contamination and cleanup process is available at:

  • Ecology’s website.

  • Seattle Public Library New Holly Branch, 7058 32nd Ave. S.

  • Ecology’s Northwest Regional Office, 3190 160th Ave. S.E., Bellevue. By appointment: 425-649-7190. 

Submit comments with Ecology’s online comment form. Or, submit comments or technical questions to Sandra Matthews, site manager, 426-649-7206, Department of Ecology, 3190 160th Ave. S.E., Bellevue WA, 98004-5452.
An Ecology fact sheet in English, Spanish, and Vietnamese, provides additional information about the site.

 Community Open House

Ecology and EPA will host an open house which will include information about the Snopac Property Site, as well as other Lower Duwamish Waterway cleanup sites:

  • Tue., June 18, 2019; 5:30 to 7:30 p.m.

  • South Seattle College – Georgetown Campus, Room C122

  • 6737 Corson Ave. S.

Contact information

Larry Altose
425-649-7009 or
Twitter: ecyseattle
Sandra Matthews
Site manager
425-649-7206 or