EPA and the Washington Department of Ecology (DOE) have released a draft study of cleanup alternatives for the five-mile Lower Duwamish Waterway CERCLA site in Seattle, Washington. The study presents a range of six alternatives with a timetable for each and compares the pros and cons of various combinations of cleanup methods, including costs and construction timelines.

The 44-acre site runs along the northern five miles of the Duwamish River, an area engineered in the early 1990s into an industrial waterway that lost much of its shoreline wetlands, marshlands and mudflats. Industrial activity and storm water runoff have since contaminated sediment in the waterway and its banks with polychlorinated biphenols (PCBs) dioxins, carcinogenic polycyclic aromatics hydrocarbons (CPAHs), and arsenic.

The draft study’s primary authors include the city of Seattle, King County, the Port of Seattle, and the Boeing Company. EPA and Washington DOE will accept comments on the draft study until December 23, 2010, and public meetings will be held December 7 and 9 in Seattle.