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Summary of Medford Carbon Monoxide (CO) Maintenance Plan


Medford, Oregon, was designated a nonattainment area for carbon monoxide (CO) and classified as moderate upon enactment of the Clean Air Act Amendments (CAAA) in 1990.

Oregon submitted a CO maintenance plan on May 31, 2001, which EPA approved on July 24, 2002 (67 FR 48388 (PDF)(6 pp, 150 K, About PDF)).

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 On January 22, 2003, EPA approved the recodified version of Oregon's rules to remove and replace the outdated numbering system (68 FR 2891 (PDF)(19 pp, 205 K)).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 plan relies on control strategies needed to maintain the CO National Ambient Air Quality Standards (NAAQS). The strategy focuses on the Federal Motor Vehicle Emission Control Program and an inspection/maintenance program.


  • 40 CFR Part 86 - Federal Motor Vehicle Emission Control Program 
  • OAR 340-024-0309 - Basic Inspection and Maintenance Program
  • OAR 340-204-0090 - Oxygenated Gasoline Control Area - Discontinued for Medford as of September 23, 2002
  • OAR 340-224-0060 - Requirements for Sources in Maintenance Areas
  • Ordinance No. 6484 - Woodstove Curtailment

Contingency Measures

  • Reinstatement of Wintertime Oxygenated Fuels Program
  • Best Available Control Technology will be replaced with requirement to install Lowest Achievable Emission Rate technology.

EPA Effective Date

September 23, 2002