On March 13, 2012, the U.S. Environmental Protection Agency (EPA; Washington, D.C.; www.epa.gov) issued a “No Action Assurance (NAA) Letter” to area source facilities required to conduct boiler tune-up by March 21, 2012, under the Area Source Rule. This means that the EPA will exercise its discretion not to pursue enforcement action against sources that fail to complete the boiler tune up by the compliance date. The NAA remains in effect for area source boilers until October 1, 2012, or until the effective date of a final rule, whichever comes first.
According to the EPA, many facilities with older affected boilers notified the agency that it was not possible to meet several tune-up requirements by the original March 2012 deadline. The tune-up requires operators to conduct stack testing to measure carbon monoxide and oxygen. However, many operators said they would have to undergo alterations, such as the installation of a sampling port or platform to conduct this type of test. In addition, the tune-up also requires that combustion be optimized consistent with manufacturer specifications, and many older boilers must be repaired in order to meet such specifications.
Area source facilities subject to the tune-up requirement include: existing coal units with heat input capacity of less than 10 million BTU per hour and existing biomass or oil units.
If a facility emits 10 or more tons per year of any single air toxic or 25 tons or more per year of any combination of air toxics, if it considered a major source facility and is subject to Boiler MACT requirements.