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Clean Air Markets

Proposed CSAPR Close-Out

Rule Summary

Determination Regarding Good Neighbor Obligations for the 2008 Ozone National Ambient Air Quality Standard

On June 29, 2018, EPA proposed to determine that the CSAPR Update Rule fully addressed 20 states' interstate pollution transport obligations for the 2008 national ambient air quality standards (NAAQS) for ground-level ozone.

EPA held a public hearing on the proposed rule on August 1, 2018, and the public comment period for the proposal ended on August 31, 2018.

Rule History

June 29, 2018 - Proposed Cross-State Air Pollution Rule Close-Out

EPA proposed that the CSAPR Update Rule fully addresses certain states’ interstate pollution transport obligations for the 2008 ozone NAAQS. 

Technical Support Documents (TSDs)

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Additional Resources