Cleaning up: Sampling at Gas Works Park slated to begin in April

After last summer’s public review and Ecology's finalization of the cleanup plan for the Gas Works Park cleanup site, sampling to collect additional information to design the cleanup is about to begin. 

The future cleanup will address contaminated groundwater and soil along a portion of the shoreline and in-water contaminated sediment. Scientists will collect groundwater, soil, and sediment samples to refine the limits of the contamination and design the cleanup. You may see workers, vehicles, and environmental sampling equipment such as drill rigs in the park and boats and barges offshore of the park.

When is the work happening?

Upland sampling work is expected to begin April 1 and last through the end of the year. In-water sampling work can only occur during specific timeframes to protect migrating salmon and other fish species in Lake Union. Some in-water sampling work may occur this spring but most of it will occur in the fall and winter. 

What happens next?

The sampling information will be used to develop an engineering design report, which will be followed by preparation of detailed design drawings and construction permit applications for the cleanup. Design and permitting is expected to take two years, with construction slated to begin in late 2027.  

Map of Gas Works Park cleanup site. The site include both land and in water areas, extending into Lake Union by about twice the length of nearby docks.

The area of investigation for the contamination cleanup