Apr 24 -- The EPA is proposing to amend the National Emission Standards for Hazardous Air Pollutants (NESHAP) for Coal- and Oil-Fired Electric Utility Steam Generating Units (EGUs), commonly known as the Mercury and Air Toxics Standards (MATS). Specifically, the EPA is proposing to amend the surrogate standard for non-mercury (Hg) metal HAP (filterable particulate matter (fPM)) for existing coal-fired EGUs; the fPM compliance demonstration requirements; the Hg standard for lignite-fired EGUs; and the definition of startup. These proposed amendments are the result of the EPA's review of the May 22, 2020 residual risk and technology review (RTR) of MATS. Comments must be received on or before June 23, 2023. The EPA will hold a virtual public hearing on May 9, 2023.
Exposure to hazardous air pollution (“HAP,” sometimes known as toxic air pollution, including Hg, chromium, arsenic, and lead) can cause a range of adverse health effects including harming people's central nervous system; damage to their kidneys; and cancer. Recognizing the dangers posed by HAP, Congress enacted Clean Air Act (CAA) section 112. Under CAA section 112, the EPA is required to set standards (known as “MACT” (maximum achievable control technology) standards) for major sources of HAP that “require the maximum degree of reduction in emissions of the hazardous air pollutants . . . (including a prohibition on such emissions, where achievable) that the Administrator, taking into consideration the cost of achieving such emission reduction, and any non-air quality health and environmental impacts and energy requirements, determines is achievable.” 42 U.S.C. 7412(d)(2). To ensure a minimum level (or “floor”) of emissions reductions, Congress required that MACT standards for existing sources “shall not be less stringent than . . . the average emission limitation achieved by the best performing 12 percent of existing sources”; and MACT standards for new sources “shall not be less stringent than the emission control that is achieved in practice by the best controlled similar source[.]” 42 U.S.C. 7412(d)(3). These requirements effectively obligated all sources to reduce emissions as well as the best sources in their category. Congress did not stop there, however. First, it required the EPA, 8 years after setting the standard, to address any residual risks posed by the source category (called the “residual risk review”). Second, and as explained in more detail below, it required the EPA, at least every 8 years on an ongoing basis, to review and revise as necessary the MACT standard taking into account developments in practices, processes and control technologies (called the “technology review”). For EGUs, Congress also required the EPA to make a one-time determination of whether it is “appropriate and necessary” to regulate this source category under CAA section 112. The EPA found regulation of EGUs “appropriate and necessary” in 2000 and reaffirmed that finding in 2012 and 2016. MACT standards were originally set for EGUs in 2012, and those standards remain in place today. In 2020, the EPA conducted the 8-year residual risk and technology review and determined not to update the MACT standard.
On January 20, 2021, President Biden signed Executive Order 13990, “Protecting Public Health and the Environment and Restoring Science to Tackle the Climate Crisis” (86 FR 7037; January 25, 2021). The Executive order, among other things, instructed the EPA to review the 2020 final rule titled, “National Emission Standards for Hazardous Air Pollutants: Coal- and Oil-Fired Electric Utility Steam Generating Units—Reconsideration of Supplemental Finding and Residual Risk and Technology Review” (85 FR 31286; May 22, 2020) (2020 Final Action) and to consider publishing a notice of proposed rulemaking suspending, revising, or rescinding that action. The 2020 Final Action included a finding that it is not appropriate and necessary to regulate coal- and oil-fired EGUs under CAA section 112 as well as the RTR for the MATS rule. The results of the EPA's review of the 2020 appropriate and necessary finding were proposed on February 9, 2022 (87 FR 7624) (2022 Proposal) and finalized on March 6, 2023 (88 FR 13956). In the 2022 Proposal, the EPA also solicited information on the performance and cost of new or improved technologies that control hazardous air pollutant (HAP) emissions, improved methods of operation, and risk-related information to further inform the EPA's review of the 2020 MATS RTR. This action presents the proposed results of the EPA's review of the MATS RTR.
In particular, with respect to the standard for fPM (as a surrogate for non-Hg metals), and the standard for Hg from EGUs that burn lignite coal, the EPA proposes to conclude that developments since 2012—and in particular the fact that the majority of sources are vastly outperforming the MACT standards with control technologies that are cheaper and more effective than the EPA forecast while a smaller number of sources' performance lags behind—warrant strengthening these standards. While the 2012 MATS drove critical HAP reductions at much lower cost than estimated, coal-fired EGUs still emit a substantial amount of HAP and developments since 2012 provide opportunities to address these emissions and ensure that all coal-fired EGUs are performing at levels achievable by the fleet. These proposed revisions would ensure that the EPA's standards continue to fulfill Congress's direction to require the maximum degree of reduction of HAP while taking into account the statutory factors. . . .
C. What are the cost impacts? The power industry's compliance costs are represented in this analysis as the change in electric power generation costs between the baseline and policy scenarios. . . .
D. What are the economic impacts? This proposed action has energy market implications. The power sector analysis supporting this action indicates that there are important power sector impacts that are worth noting, although they are small relative to recent market-driven changes in the sector and compared to some other EPA air regulatory actions for EGUs. . . .
E. What are the benefits? Pursuant to E.O. 12866, the RIA for this action analyzes the benefits associated with the projected emissions reductions under this proposal to inform the EPA and the public about these projected impacts. This proposed rule is projected to reduce emissions of Hg and non-Hg metal HAP, PM2.5, SO2, NOX, and CO2 nationwide. . . .
We solicit comments on this proposed action. In addition to general comments on this proposed action, we are also interested in additional data that may improve the analyses. We are specifically interested in receiving any information regarding developments in practices, processes, and control technologies that reduce HAP emissions. We are also interested in comments on any reliance interests stakeholders may have that would be affected by this proposed action. . . .
FRN:
https://www.federalregister.gov/d/2023-07383 [43 pages]
