Background

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)).

Summary

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.

Rules

• 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