Status of Exceptional Events Implementation Guidance Colleen McKaughan, Associate Director U.S. EPA, Region 9 Air Program Update for WESTAR Fall Business Meeting November 1, 2011 Disclaimer: Positions and views expressed here represent draft EPA guidance and/or staff recommendations and not final Agency policy

Background 2007 Exceptional Events Rule Provides mechanism by which air quality data can be excluded from regulatory decisions and actions Affects design value calculations, NAAQS designation status, and State Implementation Plan development Since promulgation, S/L/Ts have encouraged EPA to develop guidance to: Clarify expectations Streamline the implementation process May 2, 2011 – EPA releases draft guidance documents Overview note to reviewers Frequently asked questions (~30 pages) High Winds Guidance Document (~60 pages) Website http://www.epa.gov/ttn/analysis/exevents.htm

Comments on Draft Guidance June 30, 2011 – Initial comment period closes 29 commenters 3 tribes, 6 states, 13 local agencies, 4 government associations, 1 industry, 1 OAQPS, 1 FLM Overview of Comments Some commenters questioned appropriateness of 25 mph wind speed threshold (including support for higher and lower thresholds, suggestions of different averaging times, and questioning overall definition) Some commenters disliked use of recurrence to determine rigor of controls analysis Some commenters requested clarification of “reasonable controls” and “not reasonably controllable or preventable.” Some commenters expressed feeling that controls analysis should not be part of EE review. Commenters expressed general support for High Wind Action Plan (HWAP) concept but some also requested clarification of HWAP implementation elements

Comments on Draft Guidance Overview of Comments Some commenters expressed concern regarding complexity of submittals (even with draft guidance) versus resource availability Some commenters emphasized that EPA should review all submittals versus only “prioritized” submittals, others agreed with prioritization Some commenters expressed desire for rulemaking versus issuing final guidance (mostly on the basis of providing clarity) Some commenters expressed desire for a formal dispute resolution process when S/L/Ts disagree with initial concurrence decision Some commenters request that we remove “but for” (some due to our lack of quantitative guidance, but also because of the impact on design values)

Next Steps: Schedule November – send response to comments document to original commenters December – release revised draft guidance documents for formal comment with a series of “charge questions” Early 2012 – finalize guidance documents Rule development (if applicable) to follow comment period Release of revised draft guidance likely to include summary of previous comments and responses Intent of Charge Questions is to reduce number of repeat comments and solicit input on areas of disagreement (e.g., submittal streamlining mechanisms)