On October 26, 2015, the EPA strengthened the NAAQS for ground-level ozone to 70 parts per billion (ppb). Murray Energy Corporation sued the EPA in September 2016 challenging the new NAAQS. On August 1, 2018, the EPA filed a final status report for this case stating it does not intend to revisit the 2015 NAAQS. Instead, the EPA stated it intends to consider topics related to background ozone as part of the next ozone NAAQS review due in October 2020. Specifically, the review will include assessments of the relative contribution of natural and anthropogenic ozone to design values (i.e., values used to determine whether areas are attaining the NAAQS).

In accordance with the Clean Air Act, each state is required to submit a State Implementation Plan (SIP) to the EPA to provide for the implementation, maintenance, and enforcement of a newly promulgated or revised NAAQS. As stated in its August 20, 2018 Potpourri notice, the Louisiana Department of Environmental Quality (LDEQ) will submit a draft SIP revision for the ozone NAAQS in two parts: Part I will include all elements except for Section 110(a)(2)(D), and Part II will include the good neighbor provisions outlined in Section 110(a)(2)(D). A copy of the draft SIP may be viewed online at the LDEQ Electronic Document Management System (EDMS) under Agency Interest #174156 or at the LDEQ headquarters in Baton Rouge. Written comments regarding the SIP revisions are due no later than 4:30 p.m. on September 20, 2018.

If you have any questions about this article, please contact the Baton Rouge office.