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Summary of Portland-Vancouver (Portland portion) and Salem-Keizer Ozone Maintenance Plan


The Portland-Vancouver air quality maintenance area (AQMA) was designated an interstate ozone nonattainment area and was further classified as marginal upon enactment of the Clean Air Act Amendments in 1990.

The Salem-Keizer Area was designated “nonattainment/insufficient data”.

On August 30, 1996 the State of Oregon submitted an ozone maintenance plan for the Portland portion of the AQMA and requested redesignation of the area to attainment. The State of Washington submitted an ozone maintenance plan on June 13, 1996 for the Vancouver portion of the AQMA. The EPA approved the plans on May 19, 1997 (62 FR 27204 (PDF)(6 pp, 141 K, About PDF)).

On April 30, 2004 (69 FR 23858 (PDF)(95 pp, 537 K)), the EPA designated areas for the 1997 8-hour ozone standard and the Portland portion of the AQMA and the Salem-Keizer area were designated attainment/unclassifiable.

On June 15, 2005, the 1 hour ozone standard was revoked. The EPA had set forth anti-backsliding provisions that required maintenance plans under section 110(a)(1) of the Clean Air Act (CAA) for areas that were designated attainment/unclassifiable for the 8-hour ozone standard if the area had also been previously designated nonattainment for the 1-hour ozone standard. Areas like the Portland portion of the AQMA and the Salem-Keizer area were required to submit maintenance plans to demonstrate maintenance of the 1997 8-hour ozone standard for at least 10 years. The 110(a)(1) maintenance plan requirement did not include conformity obligations (unlike maintenance plans required under section 175A of the CAA).

On May 22, 2007, the EPA received 110(a)(1) maintenance plans prepared by the State of Oregon to maintain the 8-hour ozone standard in the Portland portion of the AQMA and the Salem-Keizer Area. The EPA proposed to approve the maintenance plans on May 6, 2010 (75 FR 24844 (PDF)(5 pp, 147 K)) and took final action on December 19, 2011 (76 FR 78751 (PDF)(33 pp, 566 K)).

On November 5, 1999, Oregon submitted a complete rule renumbering and relabeling package to EPA for approval in the SIP. On January 22, 2003, EPA approved the recodified version of Oregon's rules to remove and replace the outdated numbering system (68 FR 2891 (PDF)(19 pp, 205 K)). The following list refers to the currently approved SIP rules.


The plans rely on control strategies needed to assure maintenance of the National Ambient Air Quality Standards (NAAQS) for ozone. The strategy focuses on emission reductions from on-road vehicles, non-road vehicles, paints and household products, and industry.


  • OAR 340-024-0100 to 0360 - Oregon Motor Vehicle Inspection and Maintenance
  • OAR 340-200-0020 - General Air Quality Definitions
  • OAR 340-224-0010 - to 0070 Major New Source Review
  • OAR 340-225-0070 - Requirements for Compliance with AQRV Protection
  • OAR 340-225-0090 - Requirements for Net Air Quality Benefit
  • OAR 340-242-0500 to 520 - Gasoline Vapors from Gasoline Transfer & Dispensing Operations
  • OAR 340-242-0600 to 630 - Motor Vehicle Refinishing
  • OAR 340-022-0800 to 0860 - Repealed July 5, 2000 (65 FR 41346)
  • OAR 340-242-0700 to 0750 - Spray Paint
  • OAR 340-022-1000 to 1050 - Repealed July 5, 2000 (65 FR 41346)
  • OAR 340-242-0760 to 0790 - Area Source Common Provisions
  • OAR 340-242-0010 to 0290 - Employee Commute Options Program
  • OAR 340-242-0300 to 390 - Voluntary Maximum Parking Ratio Program
  • OAR 340-242-0400 to 440 - Industrial Emission Management Program
  • OAR 340-204-0010 to 0040 - Designation of Air Quality Areas

Contingency Measures

  • OAR 340-224-0060 - Requirements for Sources in Maintenance Areas

EPA Effective Date

June 18, 1997