The U.S. Environmental Protection Agency (EPA) has issued a final rule setting thresholds for greenhouse gas (GHG) emissions that defines when permits under the Clean Air Act are required for new and existing industrial facilities. The rule’s phase-in approach exempts all but the nation’s largest GHG emitters and reflects an increase in the threshold laid out in EPA’s 2009 proposal. Starting in January 2011, facilities already subject to the Prevention of Significant Deterioration (PSD) permitting program or the Title V operating permit program for other pollutants will be required to include GHGs in their permits if they increase their GHG emissions by at least 75,000 tons per year.  

In July 2011, the requirements will expand to all new facilities with GHG emissions of at least 100,000 tons per year and existing facility modifications that would increase GHG emissions by at least 75,000 tons per year. The rule also requires that regulated emitters use the best available control technologies to minimize GHG emissions. EPA estimates that about 550 sources will need to obtain title V permits for the first time due to their GHG emissions, and that the rule will trigger approximately 900 additional PSD permitting actions each year. The final rule and other resources are available here.