Water Quality

On January 24, 2020, the Environmental Quality Commission adopted rules that that established a multiple discharger variance for methylmercury in the Willamette Basin. The variance proposes a temporary change in the water quality standard because the current standard is not achievable due to global sources of pollution. The EQC also approved amendments to the state variance authorization rule to ensure it is consistent with recent federal variance regulations. On April 13, 2020, U.S. EPA approved adopted changes to the variance authorization rule (see attachment). U.S. EPA is still evaluating the mercury multiple discharger variance.

Related documents and links


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For more information about this rulemaking contact Aron Borok by email or phone at 503-229-5050 or Debra Sturdevant by email or phone at 503-229-6691 (toll-free at 800-452-4011).