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Summary of Thurston County Particulate Matter (PM-10) Attainment and Maintenance Plans


The Thurston County, Washington, area was designated nonattainment for PM10 and classified as moderate upon enactment of the Clean Air Act Amendments of 1990.

Washington submitted the PM10 maintenance plan on August 16, 1999. EPA approved the plan on October 4, 2000 (65 FR 59128 (PDF)(8 pp, 239 K, About PDF)).

On July 1, 2013, Washington submitted an updated maintenance plan to fulfill the second 10-year planning requirement of Clean Air Act section 175A (b) to ensure compliance through 2020. The EPA approved the plan on October 3, 2013 (78 FR 61188 (PDF)(4 pp, 240 K)).


The plan relies on control strategies needed to assure attainment of the PM10 National Ambient Air Quality Standards (NAAQS). The strategy focuses on control of residential woodsmoke and open burning.


  • WAC 173-433, Residential Wood Combustion Control Program
  • ORCAA Rule 8.1, Wood Heating
  • WAC 173-425, Outdoor Burn Ban
  • ORCAA Rule 6.2, Outdoor Burning

Contingency Measures

  • ORCAA Rule 8.1.4(e), Further reductions of residential woodsmoke emissions.

EPA Effective Date

November 4, 2013