Facilities must meet work practice standards by March 21.

The District of Columbia Circuit Court of Appeals has reinstated the original compliance date for the Boiler MACT ‑- also known as BMACT or Major Source Rule ‑- that the EPA published in the Federal Register in March 2011. The rule, which calls for the maximum achievable control technology for boilers, specifies specific emission control equipment and documenting requirements.

In a ruling on January 9, 2012, District Court Judge Paul Friedman said that a delay of the rules was “arbitrary and capricious” and negated the delay. As a result, owners and operators of certain boilers and process heaters are required to meet work practice standards outlined in the rule by March 21, 2012, and the equipment owners and operators also must install MACT equipment by March 2014.

Major source facilities are the ones affected by the newly reinstated Boiler MACT. As defined by the rule, a major source facility is one that emits 10 tons or more per year of any single air toxic, or 25 tons or more per year of any combination of air toxics. A comprehensive list of the regulated air toxics can be found on the EPA website. Very large industrial facilities such as refineries, chemical and large manufacturing plants, and large institutional facilities such as universities typically are classified as major source facilities.

If a facility is not a major source, it is classified as an area source and is required to meet a different set of regulations that are in effect. For more information about the Area Source Rule, visit http://www.epa.gov/airquality/combustion/. Milwaukee-based Cleaver-Brooks, a boiler manufacturer, also has compiled an extensive Boiler MACT wiki at www.cleaverbrooks.com/epa.

Requirements for both major source and area source facilities vary depending upon: the type of fuel combusted, boiler commissioning date and boiler size. For the Major Source Rule, EPA has identified 15 different subcategories of boilers and process heaters based on the design of the various types of units. The final rule includes specific requirements for each subcategory. Necessary actions range from conducting regular tuneups to meeting numeric emissions limits. Facilities also must maintain records and file periodic reports to demonstrate compliance.

Below is a summary of the requirements of the Boiler MACT for major source facilities. For the complete rule that is published in the Federal Register, visit http://www.gpo.gov/fdsys/pkg/FR-2011-03-21/pdf/2011-4494.pdf.
  • For all new and existing gas- and refinery gas-fired units, the operator must perform an annual tuneup for each unit. Units combusting other gases can qualify for work practice standards by demonstrating that they burn “clean fuel,” with contaminant levels similar to natural gas.

  • For all new and existing units with a heat input capacity less than 10 MMBTU/hr, the operator is required to perform a tuneup for each unit once every two years.

  • For all new and existing “limited use” boilers ‑- defined as those operated less than 10 percent of the year as emergency and back-up boilers to supplement process power needs -‑ the operator is required to perform a tuneup for each unit once every two years.

  • The final rule establishes numeric emission limits for all other existing and new boilers and process heaters located at major sources. The final rule establishes emissions limits for:

    • Mercury.
    • Dioxin.
    • Particulate matter (PM) as a surrogate for non-mercury metals.
    • Hydrogen chloride (HCI) as a surrogate for acid gases.
    • Carbon monoxide (CO) as a surrogate for non-dioxin organic air toxics.

  • The largest major source boilers are required to continuously monitor their particle emissions. All units larger than 10 MMBTU/hr must monitor oxygen as a measure of good combustion.

  • Existing major source facilities are required to conduct a one-time energy assessment to identify cost-effective energy conservation measures.
While the Area Source Rule has been in effect since being published in March 2011, the Major Source Rule has not. In May 2011, EPA issued a notice of delay and asked for a stay of the rules to give the agency more time to evaluate feedback from the industry.