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Exceptional Events Rule and Guidance

Contact:      Beth W. Palma
                    palma.elizabeth@epa.gov
                    (919) 541-5432

Exceptional Events Rule and Guidance Background

The EPA promulgated the Exceptional Events Rule in March of 2007. In May of 2013, the EPA released Interim Exceptional Events Implementation Guidance to assist air agencies in interpreting and implementing the provisions of the 2007 rule. At the same time, the EPA acknowledged the need to consider additional changes that could only be accomplished through a notice-and-comment rulemaking. This rulemaking effort resulted in proposing revisions to the 2007 Exceptional Events Rule and issuing draft implementation guidance for wildfires that may influence ozone concentrations in November of 2015. The EPA finalized these rule revisions and finalized the wildfire/ozone guidance in September of 2016. We list below the 2016 final rule revisions and guidance, the 2015 proposed rule revisions and draft guidance and the 2013 Interim Exceptional Events Implementation Guidance. We also include materials from our September 21, 2016 informational public webinar, which provide an overview of the final Exceptional Events Rule revisions and the final wildfire/ozone implementation guidance.

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