Under new rules, Michigan facilities that were minor sources may now become major sources solely because of their greenhouse gas (GHG) emissions. Michigan is amending its air quality rules to comply with recent federal changes that would require facilities that were not subject to Title V permit requirements (known as Renewable Operating Permits (ROPs) in Michigan) to apply for a Title V ROP by July 2012 if their GHG potential to emit exceeds the thresholds. The rules also incorporate new emissions thresholds for the pollutant PM 2.5.

Facilities must calculate source-wide potential to emit GHGs on a mass basis and a carbon dioxide-equivalent (CO2e) basis . The major source thresholds are source-wide potential to emit of greater than or equal to 100 tpy GHG on a mass basis, and 100,000 tpy CO2e. If these thresholds are exceeded, the facility may have to submit an ROP application by July 1, 2012. The DEQ has announced a public hearing on these rule changes for May 3, 2012, 1:00 PM in the Art Iverson conference room, Constitution Hall, Lansing. Written comments will be accepted until 5:00 PM on May 3.