EPA Finalizes Amendments to the Boiler MACT; Definitions of “Startup” and “Shutdown” are Revised

EPA recently issued a final rule that amends the Boiler MACT, the regulation that addresses emissions of HAPs from industrial, commercial, and institutional boilers and process heaters located at major sources of HAPs.  The amendments were made in response to 13 petitions for reconsideration of amendments to the rule made in 2013.  Major sources of HAPs that have affected units must comply with the rule by January 31, 2016, so owners and operators of these sources should review the changes now. 

While the amendments make a number of changes and clarifications, this article focuses on revisions made to the definitions of “startup” and “shutdown” and the work practices that apply during these periods.  The definition of “startup” now includes an alternative definition that extends startup for four hours after the boiler either supplies “useful thermal energy” for heating, cooling, or process purposes, or produces electricity, whichever is sooner.  Those using the alternative startup definition must meet enhanced recordkeeping requirements.  The definition of “shutdown” is amended to begin either when the boiler no longer supplies useful thermal energy or when “no fuel is being fed to the boiler,” whichever is sooner.  This change was made to addresses the circumstance where fuel remaining in a boiler on a grate or elsewhere continues to combust, even though fuel is no longer being fed to the boiler and useful thermal energy is no longer being generated.  Revisions to work practice standards during these periods include use of clean fuel and engagement of all applicable control devices so that emissions standards are met no later than four hours after useful thermal energy is first supplied.  

The changes to the definitions should make it easier for owners and operators of these emission units to implement the rule.  With the compliance date less than two months away, it’s important that they know how the nuances of the final rule will affect their operations.