Cleaning up: An outdoor cleanup plan inside a river bend

Aerial view of Site in riverbend of Skagit River west of Mt Vernon, WA on location of current water treatment plant

Location of site next to the Skagit River

We’re proposing to adopt a cleanup plan that would enable the city of Anacortes to begin cleanup and demolition of its former water treatment plant on River Bend Road at Mount Vernon, on the inside curve of a 180-degree bend of the Skagit River. Anacortes replaced the 1969 plant with a new facility in 2013.

The cleanup will address exterior building materials and immediately adjacent soils on the exterior of two of the former plant’s structures. The city’s water supply itself has been shown to meet all state and federal health standards.

Cleanup Action Plan figure showing removal of building materials adn soil removal around the Sedimentation and Filtration Basins.

Cleanup actions at the Anacortes Former Water Treatment Plant

Outside walls

Exterior coatings on two parts of the old plant contained PCBs, polychlorinated biphenyls. Once commonly used in commercial building coatings, some of the toxic material was absorbed a few millimeters into the concrete walls and mixed into the top inches of soil directly along those walls. PCBs were not used in the plant’s interior.

Figure displaying PCB concentrations in structure exterior walls (more concentrated on exterior, less in interior, none near treated water)

Figure displaying PCB concentrations in structure exterior walls

Based on a detailed study of the site and an evaluation of cleanup options — which we approved last year — the city has proposed a cleanup plan to implement in concert with the overall demolition of the former plant. We’ve reviewed that plan and are proposing to adopt it, subject to public review and comment.

The plan describes a process to demolish and safely dispose of the former filtration basin and sedimentation basin structures. The exterior walls and affected surrounding soils will be removed for disposal at a licensed solid waste landfill. 

Comments welcome

We’re inviting the public to review and comment on these three documents, through June 30, 2021:

  • Cleanup Action Plan: describes the cleanup work to address contamination at the site.
  • Consent Decree:  Our legal agreement with Anacortes requiring design and implementation of the work described in the Cleanup Action Plan.
  • State Environmental Policy Act-Determination of Non-Significance: Our finding — under the State Environmental Policy Act — that the cleanup work is not likely to harm the environment.

After we’ve reviewed all public comments, we’ll finalize the documents, which will enable the cleanup to proceed (subject to other permits needed for a demolition project).

Online public meeting

We will hold an online public meeting to provide more information and answer questions:

Monday, June 7, 2021

4 p.m.

To join the meeting, use this link.