Together with community, we have secured commitment to clean up cPAHs to the 2014 ROD levels (despite EPA's willingness to accept a lesser cleanup).
The public agencies (the Port of Seattle, City of Seattle, and King County) who are working on the cleanup design with EPA oversight (as part of the Lower Duwamish Waterway Group or LDWG) made an announcement at the March 2022 Roundtable meeting that they would “use the original cPAH remedial action level that was included in the 2014 ROD…” The full link to this statement from the LDWG is included below, so you can review it whenever you have time.
Please read FULL official letter from LDGW regarding cPAH standards HERE
We appreciate the input we’ve received from the community regarding the EPA’s updated cPAH action levels and clean up standard for the Lower Duwamish Waterway, as detailed in the Final Explanation of Significant Differences for cPAHs issued on September 30, 2021 (ESD). Scientific understanding of the risks from a particular toxin can change as more scientific studies are done.EPA uses information like this to update the toxicity levels that are used to determine health risks and inform Superfund cleanup designs. Sometimes a level is increased, meaning that it is found to be more harmful to human health, and sometimes the level is decreased, meaning that the science shows that the substance is less harmful to human health than previously thought.
When EPA updated the toxicity level of cPAHs after a multi-year process that included independent scientific review, work on the cleanup design for the Lower Duwamish Waterway had not started.
Therefore, it made sense to include the new national levels in the cleanup design of the Lower Duwamish Superfund Site. To do so, EPA released a Proposed Explanation of Significant Differences, a document that explains why a change is being made. After a comment period, EPA
finalized the decision they had proposed in the Explanation of Significant Differences, meaning these new levels would be incorporated in the remedy for the Lower Duwamish Waterway. (Note: These same levels had previously been incorporated into the cleanup of the Portland Harbor
Superfund site through an Explanation of Significant Differences process). We support the EPA’s updated scientific understanding of cPAH toxicity. However, we also recognize that some members of the community did not support a change to the cPAH action levels and cleanup level in the 2014 Record of Decision (ROD).
To address these concerns, the Lower Duwamish Waterway Group (LDWG) will use the original cPAH remedial action level that was included in the 2014 ROD as a basis for the engineering designs for the cleanup of the upper and middle reaches of the Lower Duwamish Waterway. The designs will include additional cleanup actions for the areas where cPAHs are above the original remedial action level, but below the current EPA-approved level.
We strongly support public involvement in the clean-up of the Lower Duwamish Waterway and look forward to working in partnership with the community to reach our common goal of protecting the environment and the health of the community.