On December 21 (2012), the US Environmental Protection Agency (EPA) announced that it has finalized revised air emissions standards for boilers and certain incinerators. The EPA announcement seemed to emphasize a “business-friendly” approach in the new rules, noting that 99 percent of the approximately 1.5 million boilers in the US will not be covered or can meet the new standards with periodic maintenance or regular tune-ups. (The total number of existing boilers subject to regulation will be about 200,000.)
Originally published in March 2011, the rule was met by an angry response from regulated industries, arguing that the proposed emission limits were unrealistic. EPA agreed to reconsider after further review.
The rules apply to boilers and process heaters that burn fuels such as natural gas, fuel oil, biomass (wood), coal, or other fuel gas, but not those that burn solid waste (unless they are exempt from emissions standards for incinerators). Separate rule revisions apply to boilers at major sources and those at area sources of hazardous air pollutants (unlike area sources, major sources have the potential to emit more than 10 tons per year of a single hazardous air pollutant, or HAP, or more than 25 tons per year of total HAPs).
For all of the 14,000 or so boilers at major sources of hazardous air pollutants, periodic tune-ups will be required. Numerical emission limits and other requirements that will apply to the “worst” of these boilers (based on fuel type and consumption) include:
- emission limits for particulate matter that are specific to the type of fuel burned in the unit
- new emission limits for carbon monoxide
- total metals emission limits as an alternative to using particulate matter as a surrogate for toxic metals
- work practice standards in lieu of numerical limits for dioxin emissions
- work practice standards instead of numerical emission limits for units burning “clean gas”, as determined by mercury content of the gaseous fuel
Existing sources will have three (3) years from the date of rule publication to achieve compliance – and may request an additional year’s delay if necessary. New sources, commencing operation on or after June 4, 2010, must comply by the date of publication or upon startup, whichever is later.
For industrial, commercial and institutional boilers at area sources:
- Boilers that burn natural gas as fuel are exempt from the rule.
- Periodic tune-ups will be required for most of the remaining boilers, and some will also require a one-time “energy assessment.
- For the few existing boilers that burn coal as fuel and for new sources (constructed on or after June 4, 2010), certain emissions limits will apply.
The initial notification date for covered boilers at area sources has been extended to January 20, 2014. The initial compliance date for boilers subject to the periodic tune-up requirement is March 21, 2014.
We will have a more detailed analysis of the compliance requirements for boilers under each of these revised rules shortly. Until then, you can obtain more information on the final standards for boilers and incinerators at the EPA webpage, www.epa.gov/airquality/combustion.