Lower Duwamish Waterway
Source Control Investigation

Terminal 117
Early Action Area 5

Aerial Photo of Terminal-117Terminal 117 is located on the west side of the river, approximately 3.5 miles south of Harbor Island. The 5.5 acre site is adjacent to the former Basin Oil Company to the west off of Dallas Avenue, the Boeing Company to the south, and the South Park Marina to the north.

Site Background

The Malarkey asphalt manufacturing plant operated on this property from 1937 until 1993. In the early 1970s, the manufacturing plant used waste oil from Seattle City Light as fuel. The waste oil contained polychlorinated biphenyls (PCBs). Site investigations from 2003 to 2008 revealed high levels of PCBs in the soil, groundwater, and sediments at this site.

Terminal 117 from the west (Ecology, 2005).  Click on photo for larger view.

Previous Cleanup Work

The Port of Seattle conducted a Superfund cleanup action with EPA oversight in 1999 and 2006 to remove PCB contaminated soil from the upland portion of the property. The Port of Seattle and the city of Seattle are currently implementing a cleanup action of the entire 5.5 acre site and portions of the surrounding residential neighborhood. This cleanup is designed to remove materials that pose a threat to the community and the environment. Ecology and EPA are overseeing this project.

Planned Sediment Cleanup Work

The proposed cleanup action of the entire 5.5 acre site is tentatively scheduled to begin in spring 2012. This cleanup action includes excavation and dredging of approximately 5,000- 10,000 cubic yards of sediment and 50,000 cubic yards of soil. Once the contaminated soil and sediments are removed, a cap will be installed and the area will be covered with clean soil. A revised Engineering Evaluation Cost Analysis will be available in the early spring of 2010. This document will be posted on the EPA website.

Source Control Action Plan Completed

As part of our ongoing source control efforts, Ecology’s consultant, reviewed information for properties located within the Terminal 117 source control area.  These property reviews provide us with information that we used to develop the Source Control Action Plan (SCAP).

South Park Marina

The South Park Marina is located adjacent to the north boundary of Terminal 117.  Ecology has determined the South Park Marina has been impacted by contamination from Terminal 117 and the site has residual contamination from a barrel reconditioning company that operated on the site in the 1950s.  Ecology’s consultant prepared a Summary of Existing Information and Identification of Data Gaps report in May 2007. 

Ecology also hired SAIC to prepare a Site Reconnaissance Plan for South Park Marina in June 2007.  Sufficient funds were available and site reconnaissance sampling and testing occurred in late summer or early fall of 2007.

Ecology’s consultant, prepared a Final Additional Site Characterization Activities Data Report for South Park Marina in June 2008.  

Ecology’s consultant, SAIC also prepared a South Park Marina, Sediment Recontamination Assessment.  The report evaluates the potential for the contamination left over from the barrel reconditioning company to recontaminate sediments after the Terminal 117 cleanup. 

Web sites related to Terminal-117 EPA

Port of Seattle T-117 Documents

This page last updated 01/04/2017