Closed Rulemaking

Chapter 173-400 WAC - General regulation for air pollution sources

Chapter 173-401 WAC - Operating permit regulation

The U.S. Environmental Protection Agency (EPA) established thresholds for greenhouse gas emissions in June 2010 that Ecology implemented through amendments to Chapter 173-400 WAC, General Regulations for Air Pollution Sources and Chapter 173-401 WAC, Operating Permit Regulation. The EPA is working on amendments that will defer greenhouse gas permitting requirements for carbon dioxide emissions from biomass-fired and other biogenic sources. The state rules need to be revised to assure the consistency of the provisions between the federal and state Clean Air Acts.

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Rule adoption


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Rule pre-proposal


Rule-making suspension
  • Director Sturdevant determined this rule making can move forward (it meets Executive Order 10-06 exemption criteria 3e). See the Rule-Making Suspension Archives page for more information.
Contact:, (360) 407-6875