The state hazardous air pollutant rules at A.A.C. R18-2-1701 to R18-2-1709 are unenforceable as a result of the final judgment of the Maricopa County Superior Court in Oak Canyon Manufacturing, et al. v. Arizona State Department of Environmental Quality, CV 2006-018439. The rules apply solely to emissions of federally listed hazardous air pollutants (HAPs) that exceed the "de minimis" amounts specified in the rule. The superior court, however, held that ADEQ does not have the authority to adopt de minimis amounts for federal HAPs.
ADEQ retains the statutory authority to designate state HAPs under A.R.S. § 49-426.04 and to specify de minimis amounts for those state HAPs under A.R.S. § 49-426.06(B) . Until ADEQ adopts rules to implement this authority, however, the state HAPs program will remain unenforceable and sources of HAPs seeking a permit need not evaluate whether they are subject to the program.
ADEQ also retains the authority under A.R.S. § 49-462 and 49-426.07 to seek injunctive relief against a source of HAPs that presents an imminent and substantial endangerment to public health and the environment.
The federal HAP standards at 40 C.F.R. Part 61 and Part 63 (incorporated by reference at A.A.C. R18-2-1101 and R18-2-1102 [Title 18 Article 11]) are separate and independent from the state HAP rules and remain fully enforceable. Sources of federal HAPs in Arizona remain obligated to comply with any applicable requirements of the federal program.