Plain-English summary
Court reverses Tenth Circuit, limits EPA's joint disapproval of 21 ozone plans
The Court reversed the Tenth Circuit and remanded, holding that EPA's single Federal Register notice disapproving 21 states' ozone implementation plans violated procedural or statutory requirements. The decision narrows how EPA can bundle multiple state-plan decisions in one notice under the Clean Air Act.
Why this matters
The ruling restricts how EPA can announce and finalize multiple state-plan decisions at once. That affects the timing and legal effect of EPA disapprovals, which can trigger federal consequences for states (like federal implementation plans or other federal actions). The decision clarifies administrative process under the Clean Air Act and may affect future EPA rulemaking and enforcement across many states.
Who may feel it
- State governments and state environmental agencies
- The Environmental Protection Agency and federal regulators
- Industries subject to state ozone controls (power plants, refineries, manufacturers)
- Communities in areas with ozone pollution
- Environmental and public-health advocacy groups
Key questions
- Does the Clean Air Act and relevant administrative procedure allow EPA to issue a single, combined Federal Register notice that disapproves multiple states' implementation plans?