Final Rule To Implement the 1997 8-Hour Ozone National Ambient Air Quality Standard: Classification of Areas That Were Initially Classified Under Subpart 1; Revision of the Anti-Backsliding Provisions To Address 1-Hour Contingency Measure Requirements; Deletion of Obsolete 1-Hour Ozone Standard Provision

The EPA is revising the rules for implementing the 1997 8-hour ozone national ambient air quality standards (NAAQS) to address certain limited portions of the rules vacated by the U.S. Court of Appeals for the District of Columbia Circuit. This final rule assigns Clean Air Act (CAA or Act) classifications and associated state planning and control requirements to selected ozone nonattainment areas. This final rule also addresses three vacated provisions of the 1997 8-hour NAAQS--Phase 1 Implementation Rule (April 30, 2004) that provided exemptions from the anti-backsliding requirements relating to nonattainment area New Source Review (NSR), CAA section 185 penalty fees, and contingency measures, as these three requirements applied for the 1-hour standard. This rule also reinstates the 1-hour contingency measures as applicable requirements that must be retained until the area attains the 1997 8- hour ozone standard. Finally, this rule deletes an obsolete provision that stayed the EPA's authority to revoke the 1-hour ozone standard pending the Agency's issuance of a final rule that revises or reinstates its revocation authority and considers and addresses certain other issues. That rule has now been issued.