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Comment period

Boeing Isaacson Thomson cleanup site, Tukwila

Comment on remedial investigation and feasibility study

Nov. 6, 2023 - Jan. 4, 2024, 11:59 p.m.

A draft environmental study and a comparison of cleanup options are available for comment.

The Boeing Isaacson Thompson cleanup site is next to the Duwamish River in South Seattle. Past industrial activities contaminated the soil and groundwater. 

We invite you to review and comment on the following documents:

  • Remedial Investigation: an environmental study done to find where the contamination is and what kinds of contamination are present at the site.
  • Feasibility Study: this identifies and evaluates a range of cleanup action options and identifies a preferred way to address the cleanup.

See the cleanup site page above for documents. 

We will host an open house in-person and online on Tuesday, Dec. 5 to answer questions about these documents.

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Comment online

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Comment by mail

David Butler
PO Box 330316
Shoreline, WA 98133-9716
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Meredith Waldref
Senior Outreach Planner

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