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Regulations & Permits > Laws, rules, & rulemaking > Rulemaking > WAC 173-400-401-Air pollution sources

Chapters 173-400 and 173-401 WAC, General Regulations for Air Pollution Sources

On February 12, 2025, Ecology adopted two rules:

  • Chapter 173-400 WAC, General Regulations for Air Pollution Sources – establishes standards and rules to control and prevent pollution from air contaminant sources
    • Update references to a new publication date for Ecology's Source Test Manual:  Procedures for Compliance Testing, a technical manual used in source testing and certification.
    • Update adoption by reference date in section -025 to adopt federal rules by reference.
  • Chapter 173-401 WAC, Operating Permit Regulation – establishes Washington's air operating permit program to comply with Title V of the federal Clean Air Act
    • Repeal the emergency affirmative defense provisions in section -645 to align with EPA's July 2023 removal of these provisions from federal operating permit regulations.

This adoption also made minor administrative updates, including updating references in two chapters of the RCW that were recodified in 2020.

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Rulemaking timeline

Timeline

Announcement phase (CR-101)

Filing date:
Jan. 18, 2024


Announcement documents

Rule development phase

Jan. 18, 2024 – Sept. 17, 2024

Public input & involvement

Public comment period (informal)
April 18, 2024, 8 a.m. – May 31, 2024, 11:59 p.m.

Comment on the draft rule and the draft source test manual
Read comments.

Ecology's meetings with stakeholders

Date Documents Location
Thursday
April 18, 2024
10 a.m. – 11:30 a.m.		 Agenda
Presentation
Draft rule language (173-400)
Draft rule language (173-401)
Draft source test manual

webinar 1
Wednesday
May 15, 2024
10 a.m. – 11:30 a.m.		 Agenda
Presentation
Draft source test manual		 webinar 1


1 Webinar information:
   Register for each webinar to get your meeting ID and passcode.
   To hear the webinar better or to call in only, use your phone (instead of the computer) to call 253‑215‑8782.

Rule proposal phase (CR-102)

Filing date:
Sept. 18, 2024

Rule proposal documents:

Comment period

Comments were due by October 31, 2024, 11:59 p.m. We accepted comments in the following ways:

  • Read comments.

  • Attend a public hearing online (webinar):  October 22, 2024, 10 a.m.

  • Mail to:  Linda Kildahl
       Department of Ecology
       Air Quality Program
       P.O. Box 47600
       Olympia, WA  98504-7600

Public hearing

Date/Time: October 22, 2024, 10 a.m. online (webinar)

Location: online (webinar)
    Register for the webinar to get your meeting ID and passcode.
    To hear the webinar better or to call in only, use your phone (instead of the computer) to call 253‑215‑8782.

Agenda: Presentation, question-and-answer session, followed by public hearing

Accessibility:  To request ADA accommodation for the public hearing, email Ecology’s ADA coordinator by October 18, 2024. Or call 360-407-6831, 711 (relay service), or 877-833-6341 (TTY).

Rule adoption phase (CR-103)

Adoption date:
Feb. 12, 2025


Rule effective date:
March 15, 2025


Rule adoption documents:

Additional languages

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Related links

Contact information

Linda Kildahl
Rulemaking Lead
linda.kildahl@ecy.wa.gov
360-706-3038

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Accessibility

To request ADA accommodation for disabilities, or printed materials in a format for the visually impaired, contact Ecology's ADA Coordinator by email at ecyadacoordinator@ecy.wa.gov, or call 360-407-6831. People with impaired hearing may call Washington Relay Service at 711. People with speech disability may call TTY at 877-833-6341.