EPA Finalizes Change to Area Source Boiler Rule
EPA has revised the National Emissions Standards for Hazardous Air Pollutants (NESHAP) for industrial, commercial and institutional boilers at area sources. The area source boiler NESHAP was initially promulgated on March 21, 2011 and is found at 40 CFR Part 63, Subpart JJJJJJ. The revisions relate to issues on which EPA granted reconsideration.
Area sources are commercial, institutional or industrial facilities that emit or have the potential to emit less than 10 tons per year of a single hazardous air pollutant or less than 25 tons per year of combined hazardous air pollutants. These sources include laundries, apartments, hotels, schools, churches, medical centers, municipal buildings, and manufacturing facilities. EPA estimates there are more than 183,000 boilers used to generate heat at area sources. The NESHAP applies to these facilities if their boiler burns coal, oil or other liquid fuel, biomass or non-waste materials. The NESHAP does not apply to gas-fired boilers, hot water heaters, residential boilers, electric boilers, or boilers that burn solid waste. (Boilers that burn solid waste are subject to the incinerator standards.)
The revisions include an exemption from the requirement to meet the particulate matter (PM) emission limit for new or reconstructed oil-fired boilers that combust only ultra-low-sulfur liquid fuel (less than or equal to 15 parts per million of sulfur). This replaces previous provisions that allowed this exemption for new or reconstructed oil-fired boilers that combust low-sulfur liquid fuel (less than or equal to 0.05 weight percent sulfur). Sources that were using the exemption for low-sulfur liquid fuel now have three years to decide how to comply with the PM limit – either convert to ultra-low-sulfur liquid fuel or conduct performance tests demonstrating compliance with the PM limit provided in the regulation. Sources using the ultra-low-sulfur fuel exemption must monitor and record the type of fuel they combust on a monthly basis. Also, if these sources intend to burn a fuel other than ultra-low-sulfur fuel or gaseous fuels, a performance test is required within 60 days of burning the new fuel.
Another change to the NESHAP applies to the frequency of PM performance testing. Previously, additional PM testing was not required for boilers with initial compliance tests showing that PM emissions were equal to or less than half of the limit provided in the regulation. Now PM performance testing is required every five years for these boilers. Sources that previously demonstrated compliance by showing that PM emissions were equal to or less than half of the limit now have until September 14, 2021 to conduct the additional performance testing.
In addition, a revision was made to the provision applicable to area source coal-fired boilers that use fuel sampling as their initial compliance test to demonstrate compliance with the mercury emission limit. As revised, if the initial performance test shows that mercury in the fuel is equal to or less than half of the mercury emission limit in the NESHAP, then further fuel sampling does not need to be conducted for 12 months as long as the source continues to use the same fuel. Previously, no additional fuel analysis was required if the initial performance test showed that the mercury level in the fuel was equal to or less than half of the mercury emission limit in the NESHAP.
The revisions also include minor changes to the definitions of startup and shutdown as well as some technical corrections and clarifications. The affirmative defense for malfunctions was removed from the NESHAP in light of the decision by the U.S. Court of Appeal for the District of Columbia Circuit in NRDC v. EPA.
81 Fed. Reg. 63112 (Sept. 14, 2016).