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Summary of Northern Ada County (Boise) Second 10-Year Carbon Monoxide Limited Maintenance Plan


Northern Ada County (Boise), Idaho, was designated nonattainment for carbon monoxide (CO) and classified as “not classified” upon enactment of the Clean Air Act Amendments in 1990.

Idaho submitted a CO maintenance plan on January 17, 2002 and EPA approved the plan on October 28, 2002 (67 FR 65713 (PDF)(6 pp, 148 K, About PDF)).

On February 10, 2011, Idaho submitted a second 10-year CO maintenance plan. EPA approved the second 10-year CO maintenance plan on August 2, 2012 (77 FR 45962 (PDF)(4 pp, 243 K)).


  • 40 CFR Part 86 - Federal Motor Vehicle Emission Control Program
  • Motor Vehicle Emissions Control Ordinance, Air Quality Board (January 1, 2010)
  • Ada County, 1999 Motor Vehicle Emissions Control Ordinance (June 15, 1999)
  • City of Boise, 1999 Motor Vehicle Emissions Control Ordinance (July 20, 1999)
  • City of Eagle, 1999 Motor Vehicle Emissions Control Ordinance (April 27, 1999)
  • Garden City, 1991 Motor Vehicle Emissions Control Ordinance (August 13, 1996)
  • City of Meridian, 1999 Motor Vehicle Emissions Control Ordinance (June 1, 1999)
  • Boise City Woodburning Ordinance and Boise City Burning Ban Enforcement Procedures, January 1, 1990
  • Wood Smoke Control Ordinances for the Cities of Garden City, Meridian, and Eagle, and for unincorporated Ada County