A recent move by the EPA puts communities across the country at risk. By rolling back a key policy that protects people against cancer-causing air pollutants, EPA Administrator Scott Pruitt is exposing us all to more toxic air.
For the past twenty years, strict controls on toxic air pollutants emitted by large industrial sources have resulted in significant societal benefits. Industrial sources such as power plants and petrochemical facilities emitting large quantities of hazardous air pollutants (HAPs for short) have been regulated by the EPA as “major sources” of these pollutants and required to apply Maximum Achievable Control Technology (or MACT), the gold standard for reducing emissions of toxics like benzene or perchloroethylene. HAPs are in a different category than greenhouse gases and other non-toxic air pollutants, as they are known to cause cancer and birth defects, as well as have detrimental environmental effects.
In 1995, HAPs were considered by EPA so detrimental to human and environmental health that once a source pollutes beyond a designated threshold, it must always apply MACT, even if at any point in time the source demonstrates it has the potential to emit below the threshold. This is what is known as the “once in, always in” (OIAI) policy. As reported by UCS before, effective implementation of MACT is projected to reduce industrial toxic pollutants by about 1.7 million tons, keeping our air free of these dangerous substances. MACT has been effective because it required major sources emitting at least 10 tons per year (tpy) of any one toxic pollutant, or 25 tpy of any combination of toxic pollutants, to forever apply the maximum achievable control technologies and processes to reduce those emissions. This would guarantee less exposure to toxic pollutants that are known to result in higher rates of cancer.
But the EPA has recently changed the rules that protect the public from major sources of toxic pollutants. Scott Pruitt’s EPA reversed the OIAI policy, allowing sources to petition the EPA to be reclassified from a federally-regulated major source to a state-regulated area source and in the process allow the source to get rid of the MACT requirement to reduce emissions.
While the rule change may appear obscure, it could have large national-scale detrimental impacts on public health. For example, most states adopt another federal air pollution safeguard—the National Emission Standards for Hazardous Air Pollutants (NESHAP), but without major source pollution protections, HAPs may not be regulated as stringently because there may be no MACT requirement. In other words, industrial facilities can avoid having to control pollution like they did as a major source. Under the new policy, Pruitt’s EPA threatens public health by regulating a petrochemical facility as it would a laundromat.
Area sources are still required to control HAP emissions but if done by means other than MACT, those reductions will not be as effective and toxic emissions could increase. Reporting and monitoring requirements are also different for area sources, which raises some questions: How would the EPA or the public know if an area source has increased HAP emissions over the major source thresholds? Thus, when, if ever, would such sources be required to go back to the major source classification? The new policy guidance is silent on these questions, and answers are critical to continued protection of public health. Worst of all, the EPA has changed the policy without any scientific analysis–let alone public input–to assess what the impacts to public health may be. As is typical in this administration’s EPA, no proof of their claims of better protecting public health has been offered.
As of 2016, there are nearly 2,800 major sources of toxic air pollution subject to MACT.
The Union of Concerned Scientists is conducting analysis to assess the potential emissions increase from allowing major sources to backslide into area sources. We are digging into the numbers to help communities nationwide speak up about this dangerous change in the rules. For now, one thing is certain: this move doesn’t serve EPA’s mission of protecting public health and the environment. In the following weeks we will report on the findings of our analysis and provide estimates of potential backslide emissions increase from a policy change that evidently benefits businesses at the expense of public health.
