On January 2, states began the implementation of new pollution control measures designed to reduce greenhouse gas (GHG) emissions from new large power plants and refineries that emit GHGs—a leading cause of human-induced climate change—as outlined by the Environmental Protection Agency (EPA). What are the new GHG standards and who do they apply to? What changes are coming in the months and years ahead? Here is a brief background and timeline of the new GHG regulations.

The new GHG standards fall under the Clean Air Act (CAA), which was passed in 1970 during the Nixon administration, and updated in 1990 during the George H.W. Bush administration. This law defines the EPA’s roles and responsibilities to protect and improve the nation’s air quality. It is important to note that while the EPA oversees compliance with the CAA, individual states are in control of issuing air permits that abide by the CAA. (Arizona and Texas did not adapt their air permit programs to comply with GHG standards of the CAA, so the EPA decided it would take over the issuing of air permits in those states until such a time that the state can resume compliance.)

Under the new GHG standards, newly-constructed or modified facilities that would have to obtain air permits anyway based on previous non-GHG pollution standards now are required to go through an added GHG analysis for their air permit. This applies to facilities that would add more than 75,000 tons of carbon dioxide (or mix of an equivalent amount of CO2 and other GHGs). Starting in July 2011, all new facilities that emit more than 100,000 tons of CO2 (or equivalent GHG mix) per year have to do the analysis, which would determine if GHG pollution controls are warranted, feasible and cost-effective. The same requirement will apply to existing facilities undergoing major modification that would result in an annual increase of more than 75,000 tons of CO2 (or a mix).

The analysis is called Best Available Control Technology, or BACT. BACT is a five-step process, that begins with identifying available technologies that could lower GHG emissions. For example, a coal plant could explore energy efficiency improvements to its operations as well as carbon capture and sequestration (CCS) — a process of pumping carbon dioxide into underground formations. The second step assesses the technical feasibility of applying the technology to the facility. Air permit applicants would have to answer questions like, “has this technology already been demonstrated elsewhere?”, “is it commercially available?”, and “can it be reasonably installed?” This step eliminates technically infeasible measures.

The third step in BACT ranks the options based on overall effectiveness at regulating the GHG emissions from the plant or refinery. The fourth step analyses the economic, energy, and environmental impacts of each remaining measure. However, the economic impact has to be assessed relative to the cost of the pollutant removed by the technology, not solely the affordability of the emissions control technology. Some options may be eliminated in this step. The fifth step in BACT is selection. Whichever option is left at the top of the ranking is then considered the best available. It is up to the permitting authority (usually state air quality agencies) to issue the air permit based on the outcome of the BACT process.

The new air permits for GHGs do not apply to all existing sources of GHGs, like cars, trucks, or even smaller power plants (see timeline below).

A short timeline of EPA action on GHGs

May 2007: The U.S. Supreme Court ruled in Massachusetts v. EPA that GHGs are air pollutants covered by the CAA. The EPA may regulate GHGs if they find them to be a danger to human health.

December 2009: The EPA issued its “Endangerment Finding” on GHGs, which found that current and projected levels of six GHGs threaten the health and human welfare of current and future generations.

May 2010: The EPA issued its “Tailoring Rule”, which limits the GHG air permitting guidelines to stationary sources (i.e., not transportation related sources like cars and trucks).

December 2010: EPA issued guidance to states on implementing the new GHG guidelines.

January 2, 2011: New GHG air permitting began for facilities that would have to go through air permitting for non-GHG pollutants anyway.

July 2011: New GHG permitting begins for new facilities that will emit more than 100,000 tons of GHGs per year and for facilities that will undergo major modification that would result in an increase of more than 75,000 tons of GHG per year.

EPA will issue its proposed GHG guidelines under the “New Source Performance Standard” (NSPS), which states will use to develop plans for reducing emissions from existing power plants.

December 2011: EPA will propose GHG NSPS standards for existing oil refineries.

May 2012: EPA will issue final GHG standards for existing power plants.

November 2012: EPA will issue final GHG standards for existing oil refineries.

2015: EPA will complete a five-year study to examine GHG permitting for smaller sources of emissions.

For more information:

EPA and the CAA: http://www.epa.gov/air/caa/

Technical guidance: http://www.epa.gov/nsr/ghgdocs/epa-hq-oar-2010-0841-0001.pdf

EPA’s timeline: http://www.epa.gov/nsr/documents/20100413timeline.pdf

Supreme Court ruling: http://www.supremecourt.gov/opinions/06pdf/05-1120.pdf