Greenhouse Gas (GHG) Emissions & Permitting

Contact: Jim Ostrowski, 517-284-6870
Agency: Environmental Quality

On June 3, 2010, the U.S. Environmental Protection Agency (USEPA) issued a final rule that sets applicability thresholds for greenhouse gas (GHG) emissions defining when permits under the New Source Review (NSR) Prevention of Significant Deterioration (PSD) program are required for new and existing sources. This rule is known as the "Tailoring Rule."

The Tailoring Rule primarily targets sources of combustion, but it may affect other sources that are modifying or applying for new Permits to Install (PTIs). If you have emissions of any of the following pollutants, you may be affected by the Tailoring Rule:

  • carbon dioxide (CO2),
  • hydrofluorocarbons (HFCs),
  • methane (CH4),
  • nitrous oxide (N2O),
  • perfluorocarbons (PFCs), and
  • sulfur hexafluoride (SF6).

The Tailoring Rule may also affect sources that received Permits to Install before July 1, 2011 but did not begin construction by that date.

PSD Permitting

PSD permitting requirements will cover for the first time new construction projects that emit GHG emissions of at least 100,000 tons per year (tpy) even if they do not exceed the permitting thresholds for any other pollutant. Modifications at existing facilities that increase GHG emissions by at least 75,000 tpy will be subject to permitting requirements, even if they do not significantly increase emissions of any other pollutant.

Guidance Documents

GHG Calculation Tools