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Impaired Waters and TMDLs

Willamette Basin Mercury TMDL

The public comment period on this TMDL closed on February 4, 2020.

On December 30, 2019, EPA established the Willamette Basin Mercury TMDL (see documents below). We are currently reviewing the comments received during the public comment period from January 6 through February 4, 2020.

EPA’s TMDL incorporates much of Oregon’s 2019 TMDL, with the major changes being revisions of some of the load and wasteload allocations to ensure that the TMDL meets the mercury water quality standards. We encourage individuals and organizations to focus your comments on these changes and the accompanying rationale.

Questions? Contact Alan Henning (, 541-687-7360, or Keyyana Blount (, 206-553-0850.

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