State environmental regulators are beginning to develop plans designed to meet more stringent air quality standards under the Clean Air Act (CAA), including standards to protect against unhealthful levels of ground-level ozone. In doing so, many states are looking more closely at a factor that contributes to their air quality problems but that they lack any authority to address: the phenomenon of air pollution carried by prevailing winds into their jurisdictions from emission sources located not only outside their own state borders but outside the US itself. The issue of international contributions to air quality concerns has gained currency in part due to the many challenges states face in meeting the stringent nationwide air quality standards for ground-level ozone that the US Environmental Protection Agency (EPA) adopted in 2015.
Continue Reading The Foreign Factor: Accounting for International Emissions in Air Quality Planning