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Summary of Northern Ada County (Boise) PM-10 Second 10-Year Maintenance Plan


Northern Ada County (Boise), Idaho, was designated as a moderate PM10 nonattainment area upon enactment of the Clean Air Act Amendments of 1990.

Idaho submitted a maintenance plan and redesignation request on September 27, 2002, and on October 27, 2003, the EPA approved the Northern Ada County PM-10 Maintenance Plan and redesignation request (68 FR 61106 (PDF)(6 pp, 149 K, About PDF)).

On March 11, 2013 Idaho submitted a second 10-year PM10 maintenance plan, and the EPA approved the second 10-year plan on October 2, 2014. (79 FR 59435 (PDF)(4 pp, 247 K)).


The plan relies on control strategies in the September 2002 maintenance plan to maintain attainment of the PM10 National Ambient Air Quality Standards (NAAQS). The strategy focuses on major stationary sources; paved and unpaved roads; fugitive dust; residential wood combustion; and on-road and off-road mobile sources.

EPA Effective Date

November 3, 2014