As major sources gear up to meet the January 31, 2016, compliance deadline for the Boiler MACT regulation, EPA has finalized a number of revisions to the rule that might affect your facility’s compliance plans.  On November 5, 2015, EPA issued final revisions to the Boiler MACT rule, EPA’s regulation addressing HAP emissions from Industrial, Commercial, and Institutional Boilers and Process Heaters at major HAP sources.  EPA’s revisions include a number of important changes that facilities should consider when planning for compliance.  The revisions include:

Most Significant Revisions:

  • Elimination of the affirmative defense for violation of emission standards during malfunctions;
  • Definitions of “startup” and “shut down” are revised.  Definition of useful thermal energy is added.  Second option to define the end of startup is now available;
  • Clarification of the output-based emission limits for co-generation boilers;
  • Existing biomass hybrid suspension grate unit CO limit revised to 3,500 ppm;
  • Added monthly fuel moisture sampling requirement for existing biomass hybrid suspension grate units;
  • Clarification that the 10% opacity standard is not an emission standard and, instead, is an operating parameter that will be established at 10% or the highest hourly average opacity recorded during the PM performance test; and
  • Clarification that pH monitoring is not required for HCL compliance for wet scrubbers that are not acid gas scrubbers.

Additional Significant Revisions:

  • Sources may request an alternative test method such that compliance with the CO emissions limit be determined using CO2 as a diluent correction in place of oxygen at 3% and procedures for correcting for moisture when CO2 is measured on a wet basis;
  • Clarification that natural gas-fired electric generating units firing at least 85% natural gas on an annual heat input basis are exempt;
  • Clarification that boilers that become subject to a different sub-category after January 31, 2016, must be in compliance with the applicable existing source provisions for the new sub-category on the date of the fuel switch or physical change, and demonstrate compliance within 60 days of the switch;
  • Clarification that for facilities performing fuel analysis, the initial compliance demonstration requires three composite samples and for monthly fuel analysis, a single composite sample must be obtained.  For fuel analysis conducted as a part of a performance stack test, a composite fuel sample must be taken during each performance test run; and
  • Clarification of recordkeeping requirements for periods of startup.