Regulatory Actions - Final Mercury and Air Toxics Standards (MATS) for Power Plants
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EPA Finalizes Mercury and Air Toxics Electronic Reporting Provisions
July 17, 2020 - EPA finalized minor revisions to the 2012 Coal- and Oil-Fired Electric Utility Steam Generating Units National Emission Standards for Hazardous Air Pollutants, known as the Mercury Air Toxics Standards. This final action identifies data elements to be reported electronically by power plants using the Emissions Compliance and Monitoring Plan System Client Tool and extends the submission of certain reports using portable document format file through December 31, 2023. While this final action changes the format and mechanism for electronic reporting, it does not change the compliance information already required by the current rule.
EPA Finalizes Supplemental Cost Finding and Risk and Technology Review
May 22, 2020 - EPA published the completed reconsideration of the appropriate and necessary finding for the Mercury and Air Toxics Standards, correcting flaws in the 2016 supplemental cost finding while ensuring that power plants will emit no more mercury to the air than before. After primarily considering compliance costs relative to the HAP benefits of MATS, EPA is concluding that it is not "appropriate and necessary" to regulate electric utility steam generating units under section 112 of the Clean Air Act (CAA).
EPA is also taking final action on the residual risk and technology review (RTR) that is required by CAA section 112. The results from the RTR show that emissions of HAP have been reduced such that residual risk is at acceptable levels, that there are no developments in HAP emissions controls to achieve further cost-effective reductions beyond the current standards, and, therefore, no changes to the MATS rule are warranted.
Mercury and Air Toxics Standards: Subcategory of Certain Existing Electric Utility Steam Generating Units Firing Eastern Bituminous Coal Refuse for Emissions of Acid Gas Hazardous Air Pollutants Final Rule
April 15, 2020 - After evaluating information on the acid gas hazardous air pollutant emissions from electric utility steam generating units (EGUs) that burn eastern bituminous coal refuse (EBCR), EPA has established a new subcategory in the Mercury and Air Toxics Standards for these units. Coal refuse includes low-quality coal mixed with rock, clay and other material. It is usually piled near coal mines.
EPA also is establishing emission standards for these facilities to control acid gas hazardous air pollutant emissions. The new subcategory and emission standards will affect six existing EGUs that burn EBCR. All are small units operating in Pennsylvania or West Virginia. As a result of this final rule, EPA does not expect emissions to increase above current levels.
Mercury and Air Toxics Standards for Power Plants Electronic Reporting Revisions
April 3, 2020 - EPA proposed minor revisions to the 2012 Coal- and Oil-Fired Electric Utility Steam Generating Units National Emission Standards for Hazardous Air Pollutants (NESHAP), known as the Mercury Air Toxics Standards (MATS). This proposed action identifies data elements to be reported electronically by power plants using the Emissions Collection and Monitoring Plan System (ECMPS) Client Tool and extends the submission of certain reports using portable document format (PDF) file through December 31, 2023. While this proposed action would change the format and mechanism for electronic reporting, it would not change the compliance information already required by the current rule.
EPA Proposes Revised Cost Finding for MATS and Completes Risk and Technology Review
December 27, 2018 - EPA issued a proposed revised Supplemental Cost Finding for the Mercury and Air Toxics Standards, as well as the Clean Air Act required “risk and technology review.” After taking account of both the cost to coal- and oil-fired power plants of complying with the MATS rule (costs that range from $7.4 to $9.6 billion annually) and the benefits attributable to regulating hazardous air pollutant (HAP) emissions from these power plants (quantifiable benefits that range from $4 to $6 million annually), as EPA was directed to do by the United States Supreme Court, the Agency proposes to determine that it is not “appropriate and necessary” to regulate HAP emissions from power plants under Section 112 of the Clean Air Act. The emission standards and other requirements of the MATS rule, first promulgated in 2012, would remain in place, however, since EPA is not proposing to remove coal- and oil-fired power plants from the list of sources that are regulated under Section 112 of the Act.
EPA Extends E-Reporting Until July 1, 2020
June 26, 2018 - EPA extended the period during which certain electronic reports required by the Mercury and Air Toxics Standards can by submitted as PDFs. Power plants will continue to be able to submit these reports as PDF files until July 1, 2020. The extension does not change the responsibility to report compliance information and ensures the compliance information can be made available to the public.
Final Rule Extends E-Reporting
March 29, 2017 - EPA finalized portions of its proposal to streamline “e-reporting” in MATS. The final rule allows power plants to submit certain emissions reports as PDFs until July 1, 2018, while EPA works to put a single e-reporting system in place for MATS. The final rule also clarifies two mercury measurement quality assurance instructions. EPA continues to review comments on the other issues that were part of the MATS e-reporting streamlining proposal.
Proposed Rule to Streamline E-Reporting Requirements
August 23, 2016 – EPA is proposing changes to the electronic reporting requirements for MATS. This is the next step toward streamlining the “e-reporting” requirements in MATS so power plants can submit all the required emissions data through a single, familiar electronic system -- rather than two separate systems.
Denials of Petitions for Reconsideration – Startup and Shutdown Provisions
August 8, 2016 -- EPA denied two petitions for reconsideration of the startup and shutdown provisions in MATS. This means that the startup and shutdown provisions that EPA finalized in November 2014 remain in place. Following a process outlined in the Clean Air Act, EPA carefully considered the petitions which asked EPA to provide an additional opportunity for public comment on certain aspects of the work practice standards for power plants during startup and shutdown periods, among other issues. EPA denied the requests for reconsideration because the public had ample opportunity to comment on the issues during the public comment period.
Final Finding: Consideration of Cost in the Appropriate and Necessary Finding for the Mercury and Air Toxics Standards for Power Plants
April 14, 2016 - EPA is issuing a final finding that it is appropriate and necessary to set standards for emissions of air toxics from coal- and oil-fired power plants. This finding responds to a decision by the U.S. Supreme Court that EPA must consider cost in the appropriate and necessary finding supporting the Mercury and Air Toxics Standards (MATS).
March 17, 2016 - EPA finalized a number of clarifying changes and corrections to the final Mercury and Air Toxics Standards.
November 20, 2015 – After assessing costs in several different ways, EPA is proposing to find that considering costs does not alter the determination that it is appropriate to regulate the emissions of toxic air pollution from power plants. EPA is proposing this supplemental finding in response to a decision by the U.S. Supreme Court.
April 21, 2015 – EPA completed the review of the remaining requests to reconsider certain aspects of the Mercury and Air Toxics Standards (MATS) for power plants. After careful consideration, EPA has decided to deny all remaining requests - a step that affirms the agency’s approach in the final MATS rule and provides stakeholders with certainty moving forward.
March 9, 2015 – EPA issued an interim final rule that will allow owners or operators of electric generating units to submit to EPA, in PDF format, emissions and compliance reports for the Mercury and Air Toxics rule. This rule clarifies that these reports should include complete (not summary) performance test data.
December 19, 2014 – EPA is proposing a technical corrections memo on the Mercury and Air Toxics Standards for power plants that would resolve conflicts between preamble and regulatory text and clarify some of the language in the regulatory text. The public will have 30 days to review and comment on the proposal after publication in the Federal Register.
November 7, 2014 – EPA completed its reconsideration of the startup and shutdown provisions applicable to coal- and oil-fired electric utilities under the Mercury and Air Toxics Standards (MATS). This final rule includes updated definitions and work practice standards. EPA is also adjusting certain monitoring and testing requirements related to periods of startup and shutdown.
November 7, 2014 – EPA issued a direct final rule and a parallel proposed rule to allow sources to comply with the MATS reporting requirements while we revise the Emissions Collection Monitoring Plan System (ECMPS) to accept all reporting that is required in the MATS rule. The rule is the first of two rulemakings that are designed to provide a single place for industry to submit their reports and data electronically. This action allows industry to submit data in PDF form for an interim time period. EPA is publishing these reporting requirements as a direct final rule because the changes are noncontroversial and no adverse comments are anticipated. If adverse comments are received, EPA will withdraw the direct final rule and address the comments when issuing a final rule based on the parallel proposal that is being issued in conjunction with the direct final rule.
June 25, 2013 – EPA is reopening, for 60 days, the public comment period on the startup and shutdown provisions included in the November 2012 proposed updates to pollution limits for new power plants under Mercury and Air Toxics Standards. Interested groups will have the opportunity to review new information provided during the original public comment period and subsequent EPA analysis of that information.
March 28, 2013 - EPA updated emission limits for new power plants under the Mercury and Air Toxics Standards (MATS). The updates only apply to future power plants; do not change the types of state-of-the-art pollution controls that they are expected to install; and will not significantly change costs or public health benefits of the rule.
December 12, 2012 - EPA has extended the comment period on the MATS reconsideration proposal by one week - until January 7, 2013. The Office of the Federal Register mistakenly published the MATS reconsideration proposal in the "final rules" section of the Nov. 30, 2012, Federal Register, and published a correction notice stating the inaccuracy on Dec. 5, 2012. Also, EPA did not receive any requests to hold a public hearing on this proposal, so no public hearing will be held.
November 16, 2012 - EPA proposed to update emission limits for new power plants under the Mercury and Air Toxics Standards (MATS). The updates would only apply to future power plants; would not change the types of state-of-the-art pollution controls that they are expected to install; and would not significantly change costs or public health benefits of the rule. The public will have the opportunity to comment for 30 days after publication in the Federal Register and at a public hearing in Washington D.C. if one is requested.
July 20, 2012 - EPA will review new technical information that is focused on toxic air pollution limits for new power plants under the Mercury and Air Toxics Standards. This reconsideration does not cover the standards set for existing power plants.
December 21, 2011 - EPA announced standards to limit mercury, acid gases and other toxic pollution from power plants.