The Environmental Protection Agency (EPA) has released a final guidance document intended to help state, local, and tribal air agencies demonstrate how international emissions affect local air quality standards under the Clean Air Act's Section 179B. This guidance provides examples of information and analyses that agencies should consider using, and it explains a "weight of evidence" approach for evaluations. While it doesn't create regulatory requirements, it could assist agencies in meeting air quality standards by offering flexibility in the development of demonstrations showing an area's potential compliance had it not been for international emissions. The document emphasizes cooperation with existing regulatory frameworks and other suitable mechanisms without directly creating new regulations.
Simple Explanation
The EPA has shared a guide to help places in the U.S. show how pollution coming from other countries affects their air and makes it hard to be clean. This doesn't make new rules but gives them ideas on how to prove pollution problems are not all their fault.