Disproportionate Clean Air Act violations occur in communities of color throughout the United States

The United States (U.S.) Clean Air Act seeks to prevent and abate ambient air pollution, while also providing a framework to identify and address violations. Little research has examined where or how frequently violations of the Clean Air Act occur and how marginalized communities may bear a disproportionate share of these violations, despite the fact that marginalized communities experience persistent, disproportionate pollution levels and associated health impacts. Here, we leverage data on Clean Air Act enforcement and compliance together with demographic data to show that the most serious violations of the Act—high priority violations (HPVs)—predominantly occur in communities of color throughout the U.S. Specifically, we find that the number of facilities with an HPV within communities with the largest proportion of people of color is nearly two times greater than in communities with the smallest proportion. Only 6% of facilities with an HPV address their violations within the timeframe mandated by the U.S. Environmental Protection Agency, and a larger share of facilities with an HPV in disadvantaged communities do not address their violations within this timeframe compared to facilities with an HPV in non-disadvantaged communities. Enforcing agencies should improve how violations are communicated and addressed. To this end, we suggest several ways to empower individuals and communities with easy-to-access data related to Clean Air Act violations and that enforcement practices and reporting be standardized across enforcing agencies.