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Rule Making

Chapter 173-400 WAC
General Regulations for Air Pollution Sources

Chapter 173-401 WAC
Operating Permit Regulation

Overview of Rulemaking

In 2015, Ecology proposed to amend General Regulations for Air Pollution Sources, and revise the State Implementation Plan (SIP) (WSR 15-15-162). We withdrew that notice on December 16, 2016 and refiled a preproposal notice with an expanded scope and SIP revision.

Scope of rule development:

The changes focus on the General Regulations for Air Pollution Sources, Operating Permit Regulation and revising the State Implementation Plan (SIP). Because of court rulings, EPA told Ecology (and 44 other agencies) to change their current rules (a SIP Call). Under existing rules, facilities are allowed extra emissions during periods of startup, shutdown, and malfunction (SSM). EPA says industry must have emission limits during SSM.

Changes will:

  • Remove exceptions for emissions during startup, shutdown, and malfunction to comply with EPA’s direction in the startup, shutdown, malfunction SIP call. This includes provisions such as affirmative defense, director’s discretion and automatic exemption
  • Allow public notices to be posted on an agency website instead of exclusively requiring newspaper notice.
  • Simplify application of nonroad engine requirements.
  • Update federal rule language in our rules and include the definition of volatile organic compounds (VOC).
  • Correct errors.
  • Make the rules easier to understand.

Why it matters:
EPA Determinations

  • State Implementation Plan (SIP) Deficiency:
    We are doing this rulemaking because EPA determined that rules in Washington and 44 other states are inadequate to meet Clean Air Act requirements. Our existing rules exempt excess emissions during periods of startup, shutdown and malfunction from emission limitations or allow a company to avoid an enforcement action for these emissions. EPA interprets our rule as limiting the scope of EPA and citizens in any enforcement actions they may pursue in the federal courts.
    EPA directs states to correct their rule deficiencies and submit them into the SIP by November 22, 2016. Ecology will not meet this deadline. We anticipate completing rulemaking and submitting a revised SIP to EPA during the summer 2017.

  • Title V – Operating Permit Program:
    EPA extended the rationale for the SIP determination to the Tile V program and proposed to remove affirmative defense provisions that shield a source from an enforcement action. Consequently, we have expanded our rulemaking to amend Chapter 173-401 WAC on this topic.

  • Public Notice:
    EPA expanded the requirement to provide public notice of a draft Prevention of Significant Deterioration and an air operating permit. Previously, notice was required in a newspaper and documents must have been available at a physical location. Now, an agency can choose to post notice and documents on their website. Electronic public notice enables us to communicate to the public more quickly.

Nonroad Engines

Ecology received requests to revise this provision to address trivial-scale nonroad engines and other adjustments to simplify application of the requirements.

Other Background Information

The EPA SIP Call also affects the Southwest Clean Air Agency and the Energy Facility Site Evaluation Council. These two agencies must change their rules based on our new rules and send their SIP revision to EPA, which we will submit on their behalf. Neither agency can proceed with rulemaking until Ecology has finished this rule amendment.


Ecology’s process for developing a rule includes gathering input from affected stakeholders and the public, and following the steps for rule adoption.



Elena Guilfoil
(360) 407-6855

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Washington Clean Air Act
Air Quality Rules


Current Rulemaking
Closed Rulemaking