Today, EPA issued its long-awaited new National Ambient Air Quality Standard (NAAQS) proposal for ground level ozone, the federal health-based standard that states must decide how to meet. The new primary 8-hour ozone NAAQS, which EPA is proposing to set at between 65 and 70 parts per billion (ppb), represents a significant tightening of the standard from the current level of 75 ppb and would put a significant portion of the country in non-attainment. The agency is also taking comment on setting the primary NAAQS as low as 60 ppb, which could drastically expand non-attainment designations even further. The agency has also proposed tightening the secondary ozone standard, which exists to protect “public welfare” (as opposed to public health) values such as soils, water, crops, wildlife, weather, economic values, visibility and climate, and personal well-being.
Today’s proposal marks yet another substantial federal air quality action by EPA in a year that has seen, perhaps, as many significant air quality rules or court decisions as any on record. These include the U.S. Supreme Court’s validation of EPA’s Cross State Air Pollution Rule (CSPR), the Court’s ruling on the extent of EPA’s authority to regulate CO2 from stationary sources in the Utility Air Regulatory Group case, EPA’s proposed Clean Power Plan focusing on CO2 reductions from coal-fired power plants, the proposed reversal of EPA’s policy on affirmative defenses for startups, shutdowns, and malfunctions; and the Supreme Court’s recent acceptance of certiorari to review the legality of the Mercury Air Toxics Standard (MATS). Of these, it is perhaps the ozone NAAQS that poses the most serious and important consequences for businesses as well as state regulators, and even the EPA itself. A further lowering of the ozone NAAQS (it was last lowered in 2008) will significantly impact nearly every industrial sector, necessitating, in our view, widespread participation in EPA’s notice and comment process. Comments will be due 90 days after publication of the proposal in the Federal Register; although, given the significance and breadth of the rule’s potential impacts, it is possible the comment deadline will be extended. A final rule is expected by October, 2015.