States Face New Clean Air Rules

Clean Air Act regulations continue to roll out with the Environmental Protection Agency’s latest proposed rule coming the day before Thanksgiving.  

The proposed rule revises the National Ambient Air Quality Standards for ground-level ozone from 75 parts per billion, where it has been since 2008, to a range of 65 to 70 parts per billion.

The Clean Air Act requires the EPA to set National Ambient Air Quality Standards for ozone and other pollutants that allow for an adequate margin of safety to protect public health. While the EPA sets the standards, state regulators monitor the pollutants and develop implementation plans to meet the standards.

The proposed new standard, however, could be tough for many states to meet, said Clint Woods, executive director for the Association of Air Pollution Control Agencies, a membership organization focused on assisting state and local air quality agencies with implementation and technical issues associated with the federal Clean Air Act.

“When it comes to ozone, states have done a great job and much of the low-hanging fruit is gone,” he said. “When a state has to go even further, especially for a pollutant like ozone that is also naturally occurring, it could stretch very limited resources and may be difficult to bring certain areas into compliance.” 

Tropospheric ozone—or ground-level ozone—is located up to seven miles from the earth’s surface and is a colorless, invisible gas, according to the U.S. Environmental Protection Agency. It is formed when volatile organic compounds and nitrogen oxides are exposed to heat and sunlight. Both industrial sources, like storage tanks, and combustion sources—like heaters, engines, turbines and flares—can contribute to ground-level ozone.

The American Lung Association believes ozone is a human health and environmental concern. It can complicate respiratory ailments at low level exposure and can cause permanent lung damage after long-term exposure, the association contends. The people most at risk include children, people with respiratory disease, like asthma, and people who are active outdoors.

According to an EPA fact sheet, ozone levels have decreased 33 percent since 1980 thanks, in part, to control strategies developed by states 

While groups argue for the need for reduction of ozone levels, Woods said states have little room left for compliance, since many states have implemented the easier control strategies. In addition, he said some states struggle with growing background ozone.  

“Background ozone can come from a variety of sources, including emissions from Asia, the intrusion of ‘good’ stratospheric ozone to ground-level in higher elevation sites, and forest fires,” he said. “There is very little states can do to address these sources. While the Clean Air Act theoretically offers a get-out-of-jail-free card for these so-called ‘exceptional events,’ in practice this policy has required a challenging amount of work for any single state to prove their case.” 

More non-attainment areas add to the cost of the regulation and puts additional strain on state resources, according to Woods. 

“Ozone pollution is a national problem and lower standard could impact many counties that have traditionally met EPA standards. As a result, this could end up being the costliest regulation in history,” said Woods.  “In addition to the potential costs for additional emissions controls, areas that are deemed to be in non-attainment with the standard can face severe economic penalties.” 

“We all know that state budgets are tight, and the monitoring, paperwork and plan development that will be required under a tighter standard could cause additional strain for state environmental agencies that are also having to undertake resource-intensive work in new frontiers like greenhouse gases.”

States have 90 days to comment on the proposed rule; the EPA will finalize the rule by next fall.