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Summary of Salem Carbon Monoxide (CO) Maintenance Plan


Salem, Oregon, was designated nonattainment for carbon monoxide (CO) on March 3, 1978 (43 FR 9028 (PDF)(2 pp, 67 K, About PDF)).

On June 24, 1980, EPA approved the State of Oregon’s control strategy for the Salem CO nonattainment area (45 FR 42275 (PDF)(1 pg, 136 K)).

Upon enactment of the 1990 Clean Air Act Amendments, the Salem area was designated nonattainment by operation of law and identified as “not-classified” (56 FR 56818 (PDF)(3 pp, 131 K)).

Oregon submitted a CO limited maintenance plan and redesignation request to EPA on August 9, 2007. EPA approved the plan and redesignation request on December 31, 2008 (73 FR 79655 (PDF)(7 pp, 163 K)).


The plan relies on control strategies needed to maintain attainment of the CO National Ambient Air Quality Standards (NAAQS). The strategy focuses on the Federal Motor Vehicle Emissions Control Program and Best Available Control Technology for carbon monoxide emissions from major new or expanding industry.


  • 40 CFR Part 86 - Federal Motor Vehicle Emission Control Program

Contingency Measures

  • Best Available Control Technology will be replaced with requirement to install Lowest Achievable Emission Rate technology.

EPA Effective Date

March 2, 2009