PHX Reporter

Maricopa County is seeking an administrative review regarding a recent report by the Arizona Department of Environmental Quality (ADEQ). The report, dated January 7, 2025, identifies a significant portion of Maricopa County as a nonattainment area for PM2.5 particulate matter. The county argues that ADEQ's recommended boundary includes areas with businesses not contributing to PM2.5 pollution.

The Maricopa County Air Quality Department (MCAQD) has formally appealed to the Office of Administrative Hearings. They argue that ADEQ’s final report overlooked their comments, analyses, and data supporting a smaller nonattainment area.

"ADEQ’s decision has significant economic and regulatory consequences, impacting our ability to develop targeted air quality rules and permitting programs that effectively address the actual sources of PM2.5 emissions,” said Thomas Galvin, Chairman of the Maricopa County Board of Supervisors, District 2. He added that Maricopa County is committed to ensuring regulatory decisions are based on validated research and urged ADEQ to collaborate on correcting these issues.

The accuracy of the state's recommendation is crucial as it informs the U.S. Environmental Protection Agency's (EPA) final boundary designations under the Clean Air Act. These designations could impact transportation funding and influence business decisions in Maricopa County.

Data submitted by MCAQD suggests that the nonattainment boundary should be smaller since PM2.5 exceedances are mainly linked to specific sources like fireworks and wood burning.

The appeal requests that ADEQ's final report be vacated and revised using all relevant data. MCAQD remains dedicated to protecting air quality in Maricopa County through science-based and transparent regulatory decisions. They seek collaboration with ADEQ to develop an accurate boundary recommendation reflecting PM2.5 sources for effective air quality management.

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