Written by Sarah Langeliers, P.E., Senior Engineer at BBJ Group
On August 23, 2019, the Environmental Protection Agency (EPA) took final action on 11 ”Moderate” nonattainment areas for the 2008 Ozone national ambient air quality standards (NAAQS). First, the EPA determined that two of the Moderate areas (Baltimore, Maryland and Mariposa County, California) attained the Ozone NAAQS by the applicable July 20, 2018 attainment date. Second, the EPA granted an extension for two of the Moderate areas in Sheboygan County, Wisconsin (Inland Sheboygan County, Wisconsin and Shoreline Sheboygan County, Wisconsin), allowing these areas one additional year to attain the Ozone NAAQS. Third, the EPA determined that seven Moderate areas (Chicago-Naperville, Illinois-Indiana-Wisconsin; Dallas-Fort Worth, Texas; Greater Connecticut, Connecticut; Houston-Galveston-Brazoria, Texas; Nevada County (Western part), California; New York-North New Jersey-Long Island, New York-New Jersey-Connecticut; and San Diego County, California) failed to attain the Ozone NAAQS by the applicable attainment date. For failing to attain by the applicable attainment date, by operation of law, these seven areas have been reclassified as “Serious” nonattainment areas for the Ozone NAAQS.
Let’s focus on the third determination: Serious nonattainment. What does this ruling mean for owners and operators of emission sources in these seven areas?
For facilities that emit Nitrogen Oxides (NOx) or Volatile Organic Compounds (VOCs), the precursor chemicals for Ozone, the impacts are significant. As of September 23, 2019, the applicability threshold for Title V Major Source classification will drop from 100 tons per year (tpy) to 50 tpy for NOx and VOCs. As a result, affected sources in these areas will be required to either obtain a Title V Operating Permit or reduce their emissions. The threshold for major modifications will also be reduced from 40 tpy to 25 tpy. Any future project at a Major Source in these seven areas that increases NOx and/or VOC emissions by 25 tpy on or after September 23, 2019 will be subject to Nonattainment New Source Review (NNSR).
Additionally, the state local agencies implementing the Clean Air Act Title V program for the seven areas must submit State Implementation Plan (SIP) revisions to the EPA, proposing new pollution controls and/or emissions limitations in order to satisfy the statutory and regulatory requirements associated with Serious nonattainment. This will likely lead to implementation of reasonably available control technology (RACT) requirements for the newly-classified Major Sources in the seven Serious nonattainment areas (i.e., those sources that currently emit between 50 and 100 tpy of NOx and/or VOC). Lastly, the emissions offset requirements for the construction of new Major Sources in the seven areas will increase from 1.15:1 to 1.2:1.
With the Title V Major Source thresholds for NOx and VOC reduced from 100 tpy to 50 tpy, sources will be looking to reduce emissions and modify permits to avoid Title V Major Source status. This could mean adding control devices and/or taking enforceable operational limitations (sometimes referring to as taking “synthetic minor limits”). Otherwise, sources that are unable to reduce their NOx and/or VOC emissions below 50 tpy in an enforceable manner will need to apply for a Title V permit. In addition, the NNSR major modification thresholds will be a key consideration for facilities with expansion projects or other upcoming changes.
We will be following this EPA action closely and communicating with relevant state and local permitting agencies to stay informed regarding proactive permitting and compliance processes for affected sources.
The final rule published in 84 Federal Register 44238, Aug. 23, 2019 may be found here.
The author recognizes Matthew Cohn of Greensfelder, Hemker & Gale for reviewing a draft of this article.