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EPA Finds States Meet “Good Neighbor” Obligations for the 2008 Ozone Standard

Eastern States on Track to Attain 2008 Ozone Standards Based on Continued Air Quality Progress

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WASHINGTON — Today, the U.S. Environmental Protection Agency (EPA) acknowledged the progress states have made reducing ozone concentrations. Based on EPA air quality projections, the Agency has determined that the 2016 Cross State Air Pollution Rule (CSAPR) Update satisfies “good neighbor” obligations for the 2008 national ambient air quality standards (NAAQS) for ground-level ozone. “Good neighbor” obligations under the Clean Air Act (CAA) require upwind states to control their emissions so as not to cause air quality problems in downwind states.

“Under President Trump, EPA has reformed the way we set and implement national standards for ground-level ozone. These reforms are helping states meet these standards and avoid additional costly requirements,” said EPA Acting Administrator Andrew Wheeler. “For power plants covered by this program for cross-border ozone, nitrogen oxide emissions dropped by over 20 percent - roughly 80,000 tons - just since the 2016 ozone season.”

The latest EPA air quality data and modeling predict that, by 2023, there will be no remaining nonattainment or maintenance areas for the 2008 Ozone NAAQS in the CSAPR Update region (which encompasses most of the eastern United States). Once the 2016 CSAPR Update is fully implemented, upwind states in this region are not expected to contribute significantly to nonattainment or interfere with the maintenance of the 2008 ozone standards in any downwind state.

Today’s rule therefore determines that EPA and these 20 states have no obligation to establish additional requirements for sources to further reduce transported ozone pollution to satisfy “good neighbor” obligations under the 2008 ozone NAAQS.

In this action, EPA finalizes minor revisions to the existing CSAPR Update regulations to reflect that the federal implementation plans (FIPs) issued for the covered states, as well as any CSAPR Update State Implementation Plans approved by EPA to replace the CSAPR Update FIPs, fully address the CAA’s “good neighbor” provisions for the 2008 ozone NAAQS.

Earlier this year, EPA provided projected air quality modeling results for ozone in 2023, including a list of potential flexibilities, for “good neighbor” state plans under the 2015 ozone NAAQS.

EPA issued the proposal for this action on June 29, 2018. The Agency held a public hearing on August 1, 2018 in Washington, DC, and accepted public comments through August 31, 2018. EPA considered these comments as the final rule was developed.

For more information on today’s announcement, go to: