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The Exceptional Events Rule is Finally Receiving a Makeover by the EPA

Environmental & Regulatory Policy Advisor
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by Amanda Reeve

Crowds watched in mute horror as Phoenix was rapidly overtaken by an ominous thick, dark cloud that swept from ground to sky.  Moving like a giant tidal wave across the Arizona skies, it appeared to be engulfing the sun above as it roared across the state.  The event left behind a brown haze that covered every exposed surface and took days to clear from the local atmosphere.

No, this is not the depiction of the Apocalypse from a Hollywood script.  This is an actual event that occurred on July 5, 2011.  This monstrous storm, known as a haboob, is another example of the power of Mother Nature.  It made headlines across the world as photos and videos of the phenomena flooded airwaves and print media alike.  Naturally, this event caused significant exceedances of the National Ambient Air Quality Standards (“NAAQS”) for course particulate matter (“PM10”) at the air monitoring stations over a course of several days.  For states like Arizona, Nevada, and California, these dust storms greatly interfere with the ability of the state to maintain attainment of the NAAQS.  This puts the state at serious risk of having to implement even more stringent regulations, as well as jeopardizes federal grants for critical transportation and infrastructure projects.

Fortunately, these exceedances qualify as an Exceptional Event (“EE”) under the Treatment of Data Influenced by Exceptional Events final rule, more commonly referred to as the Exceptional Events Rule (“EER”), promulgated on March 22, 2007 (72 FR 13560).  The purpose of the EER is to provide a mechanism for justifying the exclusion of air quality data from regulatory decisions and actions related to an event where the normal planning and regulatory processes established by the Clean Air Act, 42 U.S.C. 7401 et seq., are not sufficient in the controlling or prevention of its occurrence.  A haboob, wildfire, or even an anthropological activity that is unlikely to recur can qualify as an EE as long as the supporting technical data sufficiently meets the criteria established in the EER.  However, since its inception, air regulatory agencies, including the EPA, have struggled with interpreting and implementing the EER consistently, efficiently and fairly.

Over the years, the states’ frustrations increased with each event for which they believed to be clearly exceptional in nature; and yet, required extensive staff hours and a significant chunk of the budget to prepare the supporting technical demonstrations to prove as much.  For instance, while the aforementioned July 2011 event is irrefutably exceptional, and was eventually deemed as such by the EPA, the State of Arizona expended a total of 615 staff hours and a cost of approximately $100,000 to generate a 214-page report demonstrating that the event-related concentrations ought to be excluded from regulatory determinations regarding Arizona’s compliance with the NAAQS (Letter from Eric Massey, Air Quality Division Director, Arizona Department of Environmental Quality, to Gregory Nudd, EPA, Region IX, March 10, 2014).  Sadly, this was considered an “easy demonstration,” especially since the event made headlines across the globe.

With these glaring inefficiencies, the EPA finally decided to revisit the rule and address the substantive concerns and administrative deficiencies.  The official unveiling of its proposed rule revising the “Treatment of Data Influenced by Exceptional Events,” and the “Draft Guidance on the Preparation of Exceptional Events Demonstrations for Wildfire Events that May Influence Ozone Concentrations” occurred on November 10, 2015.  This is certainly timely, as both are especially crucial now in light of the new more stringent ozone NAAQS final rule published on October 26, 2015 (80 FR 65292), particularly for the western states where background ozone, transport, and wildfires are all significant contributors to the ozone levels.

The EPA held a public hearing in Phoenix, Arizona at the headquarter offices of the Arizona Department of Environmental Quality on Tuesday, December 8, 2015 to receive comments on the proposed rule and associated draft guidance.  Members of the public, industry, trade associations, environmental organizations, regulatory agencies, the Western States Air Resources Council (“WESTAR”) representing air regulatory agencies of 15 states, and U.S. Senator Flake attended the hearing to provide their oral and/or written comments.  The vast majority of the comments made/submitted requested that an extension of the public comment period be granted to allow a more substantive review by the stakeholders.  Unless the EPA grants the much requested extension, public comments must be submitted by January 19, 2016 at for either/both of the following dockets:

EPA-HQ-OAR-2013-0572: Treatment of Data Influenced by Exceptional Events; and

EPA-HQ-OAR-2015-0229: Draft Guidance on the Preparation of Exceptional Events Demonstrations for Wildfire Events that May Influence Ozone Concentrations.