Clean Air Act Federal ruling could force state to work harder to regulate oil refineries By Bellamy Pailthorp • Dec 6, 2011 A big ruling in a federal suit brought against the state aims to force more regulation of one of the biggest sources of air pollution: oil refineries. Groups seek regulation for livestock air pollution By Liam Moriarty • Apr 6, 2011 EPA.gov Listen Listening... / If you put thousands of cows or chickens or hogs in a confined area, it’s likely to produce a powerful aroma. But can it harm your health? A coalition of community and environmental groups says "yes." And they're asking for regulations on high-intensity livestock operations they say violate air pollution standards.