Yesterday, November 2, 2016, EPA released a pre-publication version of proposed regulations that spell out how the Agency’s 2015 ozone National Ambient Air Quality Standard (NAAQS) will be implemented. The proposed regulations apply to states with areas that are classified as nonattainment for the 2015 standard of 70 parts per billion (ppb), as well as to states in an Ozone Transport Region.

EPA’s proposed implementation regulations closely track the implementation regulations for the 2008 ozone NAAQS, which are currently being challenged in the D.C. Circuit. South Coast Air Quality Management District v. EPA, et. al. EPA has requested comment on a number of issues presented in the proposed regulations, including:

  • ozone thresholds for determining the classifications for nonattainment areas (marginal, moderate, serious, severe and extreme),
  • attainment deadlines for each classification,
  • RACT planning and implementation deadlines,
  • whether states can consider pollution sources that are in-state, but not inside the nonattainment area, for purposes of attainment planning, and
  • whether EPA should retain optional trading provisions that allow sources required to obtain NOx or VOC emission offsets to use either NOx or VOC emission reductions to satisfy the offset requirement.

EPA has also proposed two options for revocation of the 2008 ozone NAAQS. Under the first option, the 2008 NAAQS would be revoked in all areas one year after the effective date of area designations under the 2015 standard.  Under the second option, the 2008 ozone NAAQS would continue to apply in each area designated nonattainment under the 2008 standard until that area is redesignated to attainment.  This approach mirrors the approach taken with the PM2.5 NAAQS.

There will be a 60-day comment period once the proposed regulations are published in the Federal Register.

For more information or questions related to the proposed regulations, please contact Margaret Campbell or Melissa Trimble.