The U.S. Environmental Safety Company (EPA) has denied an business petition looking for to delist stationary combustion generators from the company’s record of hazardous air pollution (HAP) main supply classes regulated below part 112 of the Clear Air Act (CAA).
The company’s remaining motion on April 11 responds to an August 2019 petition filed by a number of commerce teams that urged the company to take away the Stationary Combustion Generators supply class from its record of HAP main sources. Teams that filed the petition embody the American Gas & Petrochemical Producers, the American Petroleum Institute, the American Public Energy Affiliation, the Fuel Turbine Affiliation, the Interstate Pure Fuel Affiliation of America, and the Nationwide Rural Electrical Cooperative Affiliation.
The EPA’s denial of the petition will imply no adjustments—for now—to the Nationwide Emission Requirements for Hazardous Air Pollution (NESHAP) for Stationary Combustion Generators (40 CFR half 63, subpart YYYY). In accordance to company estimates, the supply class consists of about 1,015 stationary combustion generators at 310 services, largely at energy crops, compressor stations, and chemical crops.
Nevertheless, as POWER reported in March, the EPA may embody a proposed revision to the rule as a part of a extra “complete method” to manage “local weather, poisonous, and standards air air pollution” from “your complete fleet of pure gas-fired generators.” The method, introduced on Feb. 29, stems from the company’s latest transfer to drop necessities overlaying current pure gas-fired energy crops in its remaining Part 111 rule regulating energy sector greenhouse gasoline (GHG) emissions, which is predicted within the coming weeks.
A Vital Denial
The 2004-promulgated NESHAP for Stationary Combustion Generators stems from the EPA’s 1992 motion to determine a listing of HAP supply classes. Subpart YYYY applies to stationary combustion generators at main sources of HAP and consists of generators which might be typically operated utilizing pure gasoline, distillate oil, landfill gasoline, jet gasoline, or course of gasoline.
Because the EPA explains, “Emissions of HAP within the exhaust gases of generators are the results of combustion of the gaseous and liquid fuels.” HAP current in these exhaust gases embody formaldehyde, toluene, benzene, acetaldehyde, and metallic HAP ( for instance, cadmium, chromium, manganese, lead, and nickel). “These pollution are identified to trigger—or are suspected to trigger—most cancers or different critical hostile well being and environmental results. Formaldehyde and acetaldehyde are possible human carcinogens,” it notes.
At the moment, the EPA’s Stationary Combustion supply class consists of eight subcategories: lean premix gas-fired generators; lean premix oil-fired generators; diffusion flame gas-fired generators; diffusion flame oil-fired generators, generators that burn landfill or digester gasoline or gasified municipal stable waste; generators of lower than 1 MW rated peak energy output; emergency generators, and generators operated on the North Slope of Alaska.
Throughout the company’s 2004 rulemaking, in response to business petitions, the EPA proposed to delist the lean premix gas-fired generators, diffusion flame gas-fired generators, emergency generators, and generators situated on the North Slope of Alaska classes. On the identical time, it moved to remain the effectiveness of the NESHAP for brand new lean premix gas-fired and diffusion flame gas-fired generators. However whereas the EPA in the end acted to finalize the keep on NESHAP for brand new lean premix-gas fired and diffusion-flame generators, it by no means finalized its proposal to delist the 4 subcategories given a 2007 D.C. Circuit court docket choice. In 2022, in the meantime, the EPA eliminated the 2004-promulgated keep for new lean premix and diffusion flame gas-fired generators that have been promulgated in 2004.
In August 2019, a number of commerce teams requested the EPA to take away the Stationary Combustion Generators supply class from the record of main supply classes regulated below Part 112. The teams pointed to a danger and know-how (RTR) that the EPA proposed in April 2019 (and in the end finalized in March 2020), whose outcomes indicated that the utmost lifetime particular person most cancers danger is 3-in-1 million. Beneath Part 112, the EPA has the authority to delist supply classes if the EPA finds that the most cancers danger from HAP emissions from all stationary combustion generators is lower than the 1-in-1 million delisting threshold, they famous.
Whereas petitioners submitted revised variations to appropriate estimates, they primarily argued that delisting of the Stationary Combustion Generators supply class was warranted as a result of their analyses confirmed that each one the evaluated dangers—together with lifetime most cancers danger, acute and persistent inhalation hazards, and multi-pathway dangers for probably the most uncovered people—have been beneath acceptable thresholds. These analyses indicated compliance with statutory standards for delisting, together with displaying dangers considerably beneath the 1-in-1 million threshold for lifetime most cancers danger, they argued.
Nevertheless, on Monday, the EPA denied the petition as a result of it deemed the petition incomplete. “We have discovered that the submitted data is insufficient to find out that no supply within the class emits HAP in portions that will trigger a lifetime danger of most cancers higher than 1-in-1 million to the person within the inhabitants who’s most uncovered to emissions of such pollution from the supply,” it stated. “Now we have reached this choice based mostly on assessment of the danger evaluation and different data submitted by petitioners and on consideration of turbine testing outcomes acquired from a CAA data request.”
EPA Engaged on Future Proposals to Regulate Emissions From Fuel Generators
For now, denial of the petition “will be sure that stationary combustion generators topic to the NESHAP will proceed to be regulated, defending human well being and the setting,” the EPA confirmed on Monday.
Nevertheless, as POWER reported in March, the EPA is contemplating a proposed revision to the NESHAP for Stationary Combustion Generators to incorporate new and current sources (40 CFR half 63 subpart YYYY). It additionally plans to problem its 8-year Evaluation of the Standards Pollutant New Supply Efficiency Requirements for Stationary Combustion Generators (40 CFR half 60 subpart KKKK), alongside a rule that can deal with Part 111(d), which can cowl the GHG portion.
In the end, the three proposals shall be a part of a “suite of rulemakings” that can totally deal with GHG emissions, air toxics, and emissions of nitrogen oxides from energy sector gasoline generators. The “complete method” stems from a Feb. 29 announcement by EPA Administrator Michael Regan that seeks to maintain the forthcoming remaining Part 111 rule tightly targeted on current coal and new gas-fired energy crops.
The EPA’s Might 2023 proposed emission tips, which included stringent necessities for current gasoline generators, have been fiercely contested by business. Amongst contentions voiced by business have been that the proposed guidelines would have required sources to finally meet an emission commonplace based mostly on both the usage of carbon seize and sequestration (CCS) or co-firing with low-GHG hydrogen. Business additionally particularly railed in opposition to the EPA’s “unrealistic” timeframe, which proposed a compliance deadline of Jan. 1, 2035, for sources assembly a CCS-based commonplace and Jan. 1, 2032, for sources to satisfy a 30% hydrogen co-firing deadline (and 96% by 20238).
Whereas the EPA has not confirmed a timeline for its new method, on March 26, it opened a non-regulatory docket (EPA-HQ-OAR-2024-0135) to gather enter from the general public and stakeholders. The non-regulatory docket shall be open for public remark for 60 days – by way of Might 28, 2024.
The EPA has up to now justified the method by suggesting GHG emissions from gas-fired combustion generators will must be addressed. “Fossil-fired steam-electric EGUs are at present the most important supply of GHG emissions amongst fossil fuel-fired EGUs. In 2021, coal-fired EGUs emitted 909 MMT CO2e. However GHG emissions from these predominantly coal-fired EGUs have been reducing and are projected to proceed to take action,” it notes in a doc connected to the docket.
“In distinction, GHG emissions from pure gas-fired combustion generators have been 613 MMT CO2e in 2021 and are projected to proceed to extend, not less than into the 2030s. Most evaluation means that someday within the later 2020s, GHG emissions from pure gas-fired EGUs will surpass these from coal-fired EGUs,” it says. “For these causes, EPA believes it’s important to maneuver ahead expeditiously to develop emission tips that embody all current pure gas-fired combustion generators.”
The doc urges business and different stakeholders to share their views on seven “key framing” questions. The EPA, for instance, is looking for suggestions on varied applied sciences as a part of the Greatest System of Emission Discount (BSER) for decreasing GHG emissions from current combustion generators, together with by way of CCS, hydrogen co-firing, battery integration, and effectivity enhancements.
The questions additionally search extra enter on the incorporation of market mechanisms, reminiscent of mass-based buying and selling. Moreover, the EPA is exploring methods to subcategorize the various current combustion turbine fleet, present compliance flexibilities, and deal with issues reminiscent of reliability, environmental impacts, and new infrastructure for hydrogen and carbon dioxide. It additionally seeks enter on workforce adjustments, whereas concurrently updating associated emissions tips and requirements.
Lastly, the company asks about potential interactions between the three separate rulemakings. “Together with growing proposed emission tips for current stationary combustion turbine [electric generating units], the EPA can also be, on an identical timeline, growing proposals to assessment the factors pollutant NSPS (40 CFR 60 KKKK) for stationary combustion generators and to assessment and replace the NESHAP (40 CRF 63 YYYY) for stationary combustion generators. Are there interactions between these three rulemakings that the EPA ought to pay attention to and take into accounts?” it asks.
—Sonal Patel is a POWER senior editor (@sonalcpatel, @POWERmagazine).
