Jump to main content or area navigation.

Contact EPA Pacific Southwest Air Program

Pacific Southwest, Region 9

Serving: Arizona, California, Hawaii, Nevada, Pacific Islands, Tribal Nations

Air Actions, Arizona

Particulate Matter Actions in Yuma, AZ

Actions on this page:

May 2007: PM-10 Adequacy Finding

On May 30, 2007, EPA found that the motor vehicle emissions budgets for PM-10 in the Yuma PM-10 Maintenance Plan are adequate for transportation conformity purposes. As a result of our finding, the Yuma Metropolitan Planning Organization and the Federal Highway Administration must use the motor vehicle emissions budgets from the submitted Yuma PM10 Maintenance Plan for future conformity determinations.

For more information, and to view a copy of the adequacy notice that was published in the Federal Register, please visit the Office of Transportation and Air Quality's adequacy web page: Conformity Adequacy Review: Region 9.

March 2006: Particulate Matter in Yuma, Arizona

EPA has signed a direct final rule determining that the Yuma area in Arizona has attained the short-term (24-hour) and long-term (annual) primary National Ambient Air Quality Standards (NAAQS) for particulate matter (PM-10) based on ambient monitoring data. Yuma has not violated the PM-10 NAAQS since 1991, but gaps in the monitored data precluded a formal attainment determination for the area until the 1998-2000 period. The Clean Air Act and our regulations require three years of clean data to make this finding. Once this clean data finding is effective, the State will be relieved of certain attainment, reasonable further progress, and related requirements so long as the NAAQS continues to be met. Our action will streamline the process for the Arizona Department of Environmental Quality (ADEQ) to request redesignation of this area to attainment.

Jump to main content.