The Disposal of Coal Combustion Residuals (CCR) from Electric Utilities Rule of 2015 finalized national regulations for the safe disposal of CCRs, including coal ash, from coal-fired power plants. The rule establishes technical requirements for CCR landfills and surface impoundments under subtitle D of the Resource Conservation and Recovery Act (RCRA), the nation's primary law for regulating solid waste.

Arizona Department of Environmental Quality (ADEQ) began working on a state permit program which would replace the Federal CCR Program. Oklahoma has a similar EPA-approved state permit program for CCR, which allows facilities to comply with the state program in lieu of the Federal CCR program. Although, due to recent legal proceedings of EPA-approved state program in Oklahoma, Arizona will not pursue a state CCR program in the near future. As a result, utilities shall have to comply with the self-implementing federal CCR rule.