Site Description
Terminal 18 (T-18) is located on the eastern side of Harbor Island at 1050 SW Spokane St, Seattle, Washington, and makes up a large portion of the Harbor Island Superfund Site Cleanup Operable Unit (OU) 01 – Soil and Groundwater (S&G-OU1 or just OU1). It is bordered by East Waterway to the east and Elliott Bay to the north and spans approximately 106-acres of Harbor Island. T-18 is zoned for industrial use and is covered by an asphalt cap. The site is currently leased for shipping container storage, rail lines, roadways, and administrative buildings.
Site History
Harbor Island was one of the first sites that EPA listed as a Superfund site in 1983. Harbor Island was divided into seven OUs, with OU1 containing T-18. As part of the cleanup work, contaminated soils were removed in 1996. The Port acquired an additional 90-acres of the island in 2003 and expanded T-18. The expanded area contained contaminated soil that the Port excavated and capped completing the cleanup in 2011.
Contamination Issue
Contaminants at the site included lead, arsenic, and petroleum hydrocarbons. A smelter used on-site until 1984 was identified as a source of high metal concentrations on the property. Spills and leaks from petroleum tanks from historical operations led to localized soil contamination.
What is the Port’s Role in this Cleanup?
As the property owner, the Port led efforts to address contamination at the site, along with several other parties represented by the Harbor Island Soil & Groundwater OU Group.
Contaminated soil hot spots that exceeded cleanup goals were removed, treated on-site, or capped. Following the cleanup, a long-term groundwater monitoring program was implemented.
Status
Active cleanup work has been completed and the Site is currently in long-term groundwater monitoring, which is expected to continue through 2035 along with five-year reviews. Although contamination has been found in some wells, it has remained localized and stable since 2015.
Contact Information
Brick Spangler | Senior Environmental Program Manager | [email protected]
Additional Resources
Visit EPA’s Harbor Island Superfund Cleanup page for more information and updates on the East Waterway cleanup.
