EPA posted its final implementation rule for the 2015 ozone standard on its website November 8, 2018, the day after it was signed by Andrew Wheeler. The final rule, like the proposed rule published in November 2016, retains many of the provisions from the implementation rule for the 2008 ozone standard, including provisions related to SIP submittal deadlines, modeling and attainment demonstration requirements, Reasonable Further Progress (RFP), Reasonably Available Control Technology (RACT), and Reasonably Available Control Measure (RACM) requirements, and ambient monitoring requirements.
New provisions from the 2016 proposal that were retained in the final rule include allowing states to use inter-precursor emissions trading and requiring state agencies to consider the impacts of in-state emission sources located outside the nonattainment area and require control measures on those sources if necessary to achieve attainment by the deadline. EPA’s final rule also addresses state concerns about international transport impacts and makes clear that nonattainment areas do not have to adjoin international borders for states to make a claim under Section 179B of the Clean Air Act that international transport affects their ability to attain the 2015 ozone standard.
The final rule specifically sidesteps addressing a February 2018 ruling by the D.C. Circuit in South Coast Air Quality Management District v. EPA which stayed certain anti-backsliding requirements in the 2008 implementation rule that were also contained in the 2016 proposal. EPA has indicated that it will address any revocation of the 2008 ozone standard and related anti-backsliding requirements in a separate future rulemaking. The final implementation rule will become effective 60 days after its eventual publication in the Federal Register.