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Toxics Cleanup Program


Lower Duwamish Waterway
Source Control Investigation

Spokane Street to Kellogg Island
River Mile Click on map to view larger size.(RM) 0.0-1.0 West

Site Background 

The Spokane Street to Kellogg Island source control area is located along the western side of the Lower Duwamish Waterway (LDW) Superfund Site between RM 0.0 and 1.0 as measured from the southern end of Harbor Island.

Properties and facilities located adjacent to the LDW that could affect sediments at RM 0.0-1.0 West include the Riverside Mill LLC property and it tenants; Port of Seattle Terminal 103 and its tenants; Port of Seattle Terminal 105; General Recycling of Washington, and the former Seaboard Lumber Property, which includes the Evergreen Trails facility and Herring’s House Park.

There are 14 upland properties in the SW Dakota Street storm drain basin that could potentially affect RM 0.0 to 1.0 West. There are 13 properties or facilities within the SW Idaho Street storm drain basin that could potentially affect RM 0.0 to 1.0 West.

Facilities in the Duwamish West CSO basin that could represent potential sediment recontamination sources are included in this report. Ecology has assigned Facility/Site identification numbers to 143 facilities within the Duwamish West CSO basin.

Contamination

Sediments in the Spokane Street to Kellogg Island portion of the LDW have been impacted by chemical contaminants from various sources. Before reaching the LDW sediments the contaminants first affected upland media including surface water, groundwater, soil, and air.

The following chemicals are considered to be contaminants of concern in the Spokane Street to Kellogg Island source control area because they could possibly recontaminate Lower Duwamish Waterway sediments once it has been cleaned up.


Metals Organics
Mercury Polychlorinated biphenyls (PCBs)
Lead Polynuclear Aromatic Hydrocarbons (PAHs)
Zinc Dioxins/Furans  
  Pesticides
  Phthalates
  Other semi-volatile organic compounds


Source Control

Ecology is the lead for source control for the LDW Superfund site. Source control is the process of finding and then stopping or reducing as much as possible releases of pollution to the river.

Potential sources of sediment recontamination associated with the Spokane Street to Kellogg Island source control area include SDs, CSO outfalls, and discharges from adjacent and upland properties. Transport pathways that could contribute to the recontamination of sediments associated with the Spokane Street to Kellogg Island source control area following remedial activities include direct discharges via outfalls, surface runoff (sheet flow) from adjacent properties, bank erosion, groundwater discharges, air deposition, and spills directly to the LDW.

Source Control Action Plan

Ecology has developed a Source Control Action Plan for the Spokane Street to Kellogg Island source control area. This plan describes the source control actions that are necessary to reduce the potential for sediment recontamination. As part of the Source Control Action Plan, Ecology hired a contractor to put together a Summary of Existing Information and Data Gaps report.

Related Information

Additional Resources