|Beginning January 2, 2011, Greenhouse Gases (GHG) became a regulated pollutant and thus became subject to the air pollution permitting programs. Mississippi has adopted the “Tailoring Rule” for GHG’s which set thresholds for Greenhouse Gas (GHG) emissions that define when permits under the New Source Review Prevention of Significant Deterioration (PSD) and Title V Operating Permit programs are required for new and existing industrial facilities. The tailoring rule increases the GHG applicability threshold so that only the larger emitting sources will be subject to regulation. |
To be subject to GHG permitting, facility emissions must trigger GHG’s on both a mass and a Global Warming Potential (GWP) basis. GHG’s refer to a group of six pollutants. Emissions of gases other than CO2 are translated into CO2e by using the gases’ global warming potentials. Total GHG emissions will be calculated by summing the CO2e emissions of all of the six constituent GHGs (see Table A-1 of 40 CFR Part 98 for GWPs).
Global Warming Potential
|Carbon dioxide (CO2)|
|Nitrous oxide (N2O)|
varies (12 - 11700)
varies (6500 - 17,340)
|Sulfur hexafluoride (SF6)|
GHG permitting will be implemented in two phases. More information on GHG permitting is available in the GHG Permitting Implementation Fact Sheet.
On November 10, 2010, EPA published the BACT GHG guidance for those projects subject to PSD permitting. More information on GHG permitting and the BACT GHG guidance can be found on EPA’s website at www.epa.gov/nsr/ghgpermitting.html .
Facilities subject to air permitting must report GHG emissions on the Greenhouse Gas Emissions Summary Form. More information on Air Permitting Requirements can be found on the Environmental Permits Division Page.