GHG Mitigation under the Clean Air Act

GHG Emission Standards for Stationary Sources

Fossil Fuel-Fired Power Plants

Section 111(b) of the Clean Air Act requires EPA to set new source performance standards (NSPS) for new and modified stationary sources of emissions that cause or contribute significantly to air pollution that may reasonably be anticipated to endanger public health or welfare. The NSPS must be based on the “degree of emissions limitation achievable through the application of the best system of emission reduction [BSER] which . . . the Administrator determines has been adequately demonstrated.” 42 U.S.C. § 7411(a)(1).

Once NSPS are established for a particular type of stationary source, EPA must (with limited exception) then adopt emissions guidelines to regulate existing sources of the same type under section 111(d) of the Clean Air Act.  42 U.S.C. § 7411(d). The emissions guidelines are typically implemented by states, which must develop, and have approved by EPA, plans for controlling emissions from existing facilities in the source category. If a state fails to develop a plan, or the state plan is not approved by EPA, a federal plan will apply.

On May 9, 2024, EPA adopted a final rule establishing new NSPS for greenhouse gas emissions from certain new fossil fuel power plants and emissions guidelines for certain existing plants. 89 Fed. Reg. 39,798 (May 9, 2024). The final rule repealed the Trump-era Affordable Clean Energy Rule (discussed below) and established stricter emissions standards for certain new and existing fossil fuel-fired power plants. EPA established different standards for different sub-categories of fossil fuel power plants based on plant longevity and capacity. A summary of the new standards can be found here. (See West Virginia v. EPA in "Litigation" below.)

Litigation

Challenge to 2024 NSPS - West Virginia v. EPA

On May 9, 2024, a group of 25 states, led by West Virginia, and various private parties filed for review in the U.S. Court of Appeals for the D.C. Circuit, contending that EPA’s final rule “exceeds [EPA’s] statutory authority, and otherwise is arbitrary and capricious, an abuse of discretion, and not in accordance with law.”

On May 13, 2024, the Petitioners filed a motion to stay EPA’s final rule pending completion of the litigation. The motion to stay was unanimously denied by a three-judge panel of the D.C. Circuit on July 19, 2024. On October 16, 2024, the Supreme Court also denied an emergency stay request from the Petitioners, meaning that the final rule will remain in effect during the litigation. The case has been briefed and oral argument took place on December 6, 2024.

Biden Administration (2021-2024)

Standards for New & Existing Sources

On May 9, 2024, EPA adopted a final rule establishing new NSPS for greenhouse gas emissions from certain new fossil fuel power plants and emissions guidelines for certain existing plants. 89 Fed. Reg. 39,798 (May 9, 2024). The final rule repealed the Trump-era Affordable Clean Energy Rule (discussed below) and established stricter emissions standards for certain new and existing fossil fuel-fired power plants. EPA established different standards for different sub-categories of fossil fuel power plants based on plant longevity and capacity. A summary of the new standards can be found here. (See West Virginia v. EPA in "Litigation" below.)

First Trump Administration (2017-2020)

Standards for New Sources

On January 13, 2021, EPA finalized its revised NSPS for new fossil fuel EGUs. 86 Fed. Reg. 2,542 (Jan. 13, 2021). The final rule did not increase the carbon dioxide emissions limits for fossil fuel EGUs (as originally proposed). Notably however, in the final rule, EPA articulated a new limit on the use of section 111 of the Clean Air Act, indicating that the section could only be used to regulate GHG emissions from stationary sources if the source category is responsible for at least 3% of U.S. GHG emissions. Other sectors that are currently regulated under section 111 of the Clean Air Act—such as oil and gas facilities—could be affected, and the rule could limit EPA’s ability to issue additional regulations to control GHG emissions on new stationary sources. (See California v. EPA in "Litigation" below.)

The final rule was part of a rulemaking process prompted by an executive order from President Trump to review past regulations (discussed below). In response to the order, EPA published a notice announcing that it was reviewing and, if appropriate, would initiate proceedings to suspend, revise or rescind the rule on April 4, 2017. On December 20, 2018, EPA proposed revisions that would weaken the NSPS, allowing fossil fuel EGUs to release more carbon dioxide per megawatt hour of electricity generated. 83 Fed. Reg. 65,424 (Dec. 20, 2018).

Standards for Existing Sources

On July 8, 2019, EPA published a final rule to repeal and replace the Clean Power Plan, called the Affordable Clean Energy (ACE) Rule. 84 Fed. Reg. 32,520 (July 8, 2019). The ACE Rule did not establish any numeric emissions guidelines or targets for existing fossil fuel power plants and instead gives states wide latitude in deciding how to regulate emissions from those facilities. It defines the BSER for greenhouse gas emissions from power plants as on-site, heat-rate efficiency improvements. This definition excludes fuel switching and improvements to demand-side energy efficiency. (See West Virginia v. EPA in "Litigation" below.)

The final rule was part of a rulemaking process prompted by an executive order from President Trump to review past regulations (discussed below). In response to the order, EPA published a notice announcing that it was reviewing and, if appropriate, would initiate proceedings to suspend, revise or rescind the rule on April 4, 2017. On October 16, 2017, EPA published a proposed rule to repeal the Clean Power Plan. 82 Fed. Reg. 48,035 (Oct. 16, 2017). The proposal did not specify whether EPA would promulgate a new rule to regulate carbon dioxide emissions from existing power plants. However, on December 28, 2017, EPA issued a proposed rule to replace the Clean Power Plan with what would come to be the ACE Rule. 84 Fed. Reg. 32,520 (Dec. 28, 2017).

Executive Order to Review Past Regulation

On March 28, 2017, President Trump issued an executive order instructing EPA to review the NSPS for fossil fuel power plants and rescind or revise them as needed to promote the President’s goals of energy independence and economic growth. This order prompted EPA's rulemakings to set performance standards for both new and existing sources, discussed above. The order also directed EPA to review and rescind or re-write the proposed rule establishing federal implementation plans and model trading rules. On April 3, 2017, EPA officially withdrew that rule proposal as well as the rule proposal establishing details for the Clean Energy Incentive Program (CEIP).

Obama Administration (2009-2016)

Standards for New Sources

On October 23, 2015, EPA published a final rule establishing NSPS for carbon dioxide emissions for both new and modified power plants. 80 Fed. Reg. 64,510 (Oct. 23, 2015). The standards set numerical emissions limits for new and reconstructed coal- and natural gas-fired plants. EPA declined to set standards for certain modified coal- and natural gas-fired plants, based in part upon a need to gather more information. (See North Dakota v. EPA in “Litigation” below.)

On April 13, 2012, EPA proposed NSPS for carbon dioxide emissions from new fossil fuel-fired  EGUs. 77 Fed. Reg. 22,392 (Apr. 13, 2012). In January 2014, EPA withdrew the proposal, and then published a new proposed rule with separate standards for modern natural gas plants (combined-cycle) and other facilities, chiefly coal-fired plants. 79 Fed. Reg. 1,430 (Jan. 8, 2014). In June 2014, EPA proposed carbon dioxide emission standards for modified and reconstructed power plants. 79 Fed. Reg. 34,960 (June 18, 2014).

In December 2010, EPA entered into a settlement agreement in New York v. EPA in which it agreed to develop NSPS for GHG emissions from EGUs.

Standards for Existing Sources

On October 23, 2015, EPA published the final Clean Power Plan rule which aims to reduce carbon dioxide emissions from existing power plants by 30% below 2005 levels by 2030. 80 Fed. Reg. 64,662 (Oct. 23, 2015). To accomplish this, the rule establishes carbon dioxide emission performance rates representing the best system of emission reduction (BSER) for fossil fuel-fired electric utility steam generating units and stationary combustion turbines within each state. The rule also establishes guidelines for the development, submittal and implementation of state plans to achieve the carbon dioxide emission performance rates. (See West Virginia v. EPA in “Litigation” below.)

Prior to promulgating the final rule, EPA also proposed two associated rules which were ultimately withdrawn. The first proposal would have established two types of federal implementation plans that could take effect where states failed to submit satisfactory plans for Clean Power Plan compliance – a rate-based emission trading program and a mass-based emission trading program. Both types of plans were also presented as model trading rules that states could adopt or tailor for implementation within their energy sector. The rule would have thus created a clear pathway for compliance with the Clean Power Plan. The second proposal, the Clean Energy Incentive Program (CEIP), was originally established in the Clean Power Plan final rule to provide a mechanism whereby states could incentivize early investments in renewable energy and energy efficiency projects in low-income communities (and receive credit for these investments in their compliance plans). This rule would have established parameters for CEIP participation and implementation. For example, it would have established limits on the number of allowances or emission rate credits (ERCs) that could be allocated or issued by a state to a CEIP-eligible project per MWh generated or saved.

Litigation

Challenge to 2024 NSPS - West Virginia v. EPA

On May 9, 2024, a group of 25 states, led by West Virginia, and various private parties filed for review in the U.S. Court of Appeals for the D.C. Circuit, contending that EPA’s final rule “exceeds [EPA’s] statutory authority, and otherwise is arbitrary and capricious, an abuse of discretion, and not in accordance with law.”

On May 13, 2024, the Petitioners filed a motion to stay EPA’s final rule pending completion of the litigation. The motion to stay was unanimously denied by a three-judge panel of the D.C. Circuit on July 19, 2024. On October 16, 2024, the Supreme Court also denied an emergency stay request from the Petitioners, meaning that the final rule will remain in effect during the litigation. The case has been briefed and oral argument took place on December 6, 2024.

Challenge to 2021 NSPS - California v. EPA

On January 19, 2021, a coalition of states and cities challenged the EPA’s final rule  in the D.C. Circuit. On March 18, 2021, EPA asked the court to vacate the rule and allow the agency to rewrite it. The court granted EPA’s motion on April 5, 2021.

Challenge to 2019 ACE Rule - West Virginia v. EPA

On July 8, 2019, a coalition public health and environmental group challenged the ACE Rule in the D.C. Circuit. A coalition of states and cities followed suit on August 13, 2019. On January 19, 2021, the D.C. Circuit vacated the ACE Rule and directed EPA to go back to the drawing board to issue a new rule. On February 22, the court took final action to vacate the ACE Rule, but agreed to stay a mandate that would vacate the EPA's repeal of the Clean Power Plan so that it is clear that it would not come into effect.

On April 29, 2021, a coalition of states asked the Supreme Court to review the D.C. Circuit's ruling. The North American Coal Corporation also filed a petition with the Supreme Court. On June 30, 2022, the Supreme Court held that the Clean Air Act did not provide EPA with authority to promulgate the Clean Power Plan, resting its decision on the "major questions doctrine."

Challenge to 2015 NSPS - North Dakota v. EPA 

The 2015 NSPS were challenged by states and industry parties. One of the key issues in the case is whether partial carbon capture and storage is an adequately demonstrated technology for reducing GHG emissions from coal-fired power plants. The Sabin Center submitted an amicus brief on behalf of eleven CCS experts asserting that the technology is in fact adequately demonstrated and thus the coal NSPS is lawful.

On March 30, 2017, the D.C. Circuit Court of Appeals issued an order to delay oral argument and hold the case in abeyance indefinitely. On August 10, 2017, the court issued another order to continue holding the cases in abeyance pending further action from the administration.  As of October 2019, the case is still being held in abeyance.

Challenge to 2015 Clean Power Plan - West Virginia v. EPA

On October 23, 2015, a coalition of states, led by West Virginia, and various Industry groups challenged the final Clean Power Plan. On February 9, 2016, the U.S. Supreme Court stayed the Clean Power Plan pending review in the D.C. Circuit Court of Appeals. On January 23, 2017, State opponents of the EPA’s Clean Power Plan filed a petition for a new lawsuit, asking the D.C. Circuit Court of Appeals to review EPA’s denial of requests for reconsideration of the rule (which were filed after the rule was finalized but before the Supreme Court stayed its implementation).

On March 28, 2017, EPA submitted a motion to hold the case in abeyance pending it’s reconsideration of the Clean Power Plan rule. On April 28, 2017, the court granted EPA’s request and ordered a 60-day stay of the litigation as well as supplemental briefings on whether the case should be remanded to the agency rather than held in abeyance. The court subsequently extended the stay several times. On September 17, 2019 the court dismissed the case as moot in light of EPA’s adoption of the Affordable Clean Energy (ACE) Rule, which formally rescinds the Clean Power Plan (see above).

Oil and Gas Sector

Section 111(b) of the Clean Air Act requires EPA to set new source performance standards (NSPS) for new and modified stationary sources of emissions that cause or contribute significantly to air pollution that may reasonably be anticipated to endanger public health or welfare. The NSPS must be based on the “degree of emissions limitation achievable through the application of the best system of emission reduction [BSER] which . . . the Administrator determines has been adequately demonstrated.” 42 U.S.C. § 7411(a)(1).

Once NSPS are established for a particular type of stationary source, EPA must (with limited exception) then adopt emissions guidelines to regulate existing sources of the same type under section 111(d) of the Clean Air Act.  42 U.S.C. § 7411(d). The emissions guidelines are typically implemented by states, which must develop, and have approved by EPA, plans for controlling emissions from existing facilities in the source category. If a state fails to develop a plan, or the state plan is not approved by EPA, a federal plan will apply.

On March 8, 2024, the EPA finalized a rule to reduce air pollution emissions from certain oil and natural gas facilities. 89 Fed. Reg. 16,820 (Mar. 8, 2024). The rule regulates GHG and volatile organic compounds ("VOCs") emitted from the "Crude Oil and Natural Gas" source category, which includes various facilities used in the production, processing, and long-distance transportation of oil and natural gas. It also revises the NSPS for new and modified facilities and the emissions guidelines for existing facilities. Finally, the rule includes regulatory amendments to fill gaps left by Congress’s joint resolution of disapproval of the 2020 rule. (See Texas v. EPA in “Litigation” below.)

Litigation

Challenge to 2024 Rule - Texas v. EPA

In March 2024, two petitions for review were filed in the D.C. Circuit Court of Appeals to challenge EPA's March 2024 rule. The first petition was filed by the State of Texas and the Texas Commission on Environmental Quality. The second petition was filed by 24 states, led by Oklahoma, along with the Arizona Legislature. The Oklahoma petition contended that the final rule exceeded EPA’s authority and was arbitrary, capricious, an abuse of discretion, and not in accordance with law. As of April 12, 2024, these petitions remain pending. On October 4, 2024, the Supreme Court denied states’ application to stay the rule.

Biden Administration (2021–2024)

On March 8, 2024, the EPA finalized a rule to reduce air pollution emissions from certain oil and natural gas facilities. 89 Fed. Reg. 16,820 (Mar. 8, 2024). The rule regulates GHG and volatile organic compounds ("VOCs") emitted from the "Crude Oil and Natural Gas" source category, which includes various facilities used in the production, processing, and long-distance transportation of oil and natural gas. It also revises the NSPS for new and modified facilities and the emissions guidelines for existing facilities. Finally, the rule includes regulatory amendments to fill gaps left by Congress’s joint resolution of disapproval of the 2020 rule. (See Texas v. EPA in “Litigation” below.)

On April 28, 2021, the Senate passed a resolution under the Congressional Review Act to repeal the Trump EPA's 2020 rule eliminating methane emissions controls for the oil and gas sector. The House passed the resolution on June 25, 2021 and President Biden signed it on June 30, 2021.

First Trump Administration (2017-2020)

On September 15, 2020, EPA published a final rule with various changes to the volatile organic compound standards that limit their effectiveness in controlling pollution. 85 Fed. Reg. 57,398 (Sept. 15, 2020).

On September 14, 2020, EPA published a final rule rescinding the NSPS for methane from oil and gas production, processing, transmission, and storage facilities. 85 Fed. Reg. 57,018 (Sept. 14, 2020). Read more on the Climate Law Blog. (See California v. Regan in “Litigation” below.)

On November 8, 2017, EPA issued a notice of data availability in support of its proposed two year stay of the NSPS requirements. 82 Fed. Reg. 51,788 (Nov. 8, 2017).

On June 16, 2017, EPA proposed a two-year stay of the NSPS requirements. 82 Fed. Reg. 27,645 (June 16, 2017).

On June 5, 2017, EPA published a notice stating that it would reconsider additional requirements in the 2016 NSPS, and was staying the requirements for three months pending reconsideration. 82 Fed. Reg. 25,730 (June 5, 2017). (See Clean Air Council v. Pruitt in “Litigation” below.)

On April 4, 2017, EPA published a notice announcing that it was reviewing and, if appropriate, would initiate proceedings to suspend, revise or rescind the 2016 NSPS. 82 Fed. Reg. 16,331 (Apr. 4, 2017).

On March 28, 2017, President Trump issued an executive order instructing EPA to review the 2016 NSPS adopted during the Obama administration to control methane and volatile organic compound emissions from certain oil and gas facilities. 82 Fed. Reg. 16,093 (Mar. 28, 2017).

Obama Administration (2009-2016)

On June 3, 2016, EPA published a final rule setting NSPS for methane and volatile organic compound emissions from new, modified, and reconstructed facilities in the oil and gas sector. 81 Fed. Reg. 35,824 (June 3, 2016). Affected facilities include well sites, gathering and boosting stations, processing plants, and compressor stations. (See North Dakota v. EPA in “Litigation” below.)

Litigation

Challenge to 2024 Rule - Texas v. EPA

In March 2024, two petitions for review were filed in the D.C. Circuit Court of Appeals to challenge EPA's March 2024 rule. The first petition was filed by the State of Texas and the Texas Commission on Environmental Quality. The second petition was filed by 24 states, led by Oklahoma, along with the Arizona Legislature. The Oklahoma petition contended that the final rule exceeded EPA’s authority and was arbitrary, capricious, an abuse of discretion, and not in accordance with law. As of April 12, 2024, these petitions remain pending. On October 4, 2024, the Supreme Court denied states’ application to stay the rule.

Challenge to 2020 Rule - California v. Regan

On September 14, 2020, a coalition of states and environmental organizations filed petitions for review of EPA’s 2020 rule to rescind the NSPS for methane from oil and gas facilities. The following day, the petitioners filed an emergency motion to stay the rule pending the court’s review, which the court denied. The case was ultimately held in abeyance and then dismissed following Congress’s joint resolution of disapproval.

Challenge to Stay of 2016 NSPS - Clean Air Council v. Pruitt

On June 5, 2017, environmental organizations filed a petition for review of the notice of reconsideration and partial stay of the 2016 NSPS. On July 3, 2017, the U.S. Court of Appeals for the District of Columbia Circuit vacated the initial three month stay of the rules, holding that the EPA lacked authority under the Clean Air Act to issue the stay. The court issued a mandate, requiring EPA to begin implementing the rules. The mandate was delayed for 14 days on July 13, 2017, “to give EPA time to determine whether to seek panel rehearing, rehearing en banc, or pursue other relief.” The 14 day period ended on July 28, 2017. On July 31, 2017, a majority of the full court of the U.S. Court of Appeals for the District of Columbia Circuit ordered “the Clerk to issue the mandate . . . forthwith,” requiring EPA to begin implementing the rules.

Challenge to 2016 NSPS - North Dakota v. EPA

The methane emission standards were challenged in the D.C. Circuit Court of Appeals. State and industry petitioners argued that the rule exceeded EPA’s statutory authority, was unconstitutional, and was arbitrary, capricious, an abuse of discretion, and not in accordance with law. On January 24, 2017, state and industry petitioners filed a motion asking the D.C. Circuit Court of Appeals to delay the briefing schedule to “allow time for new administration personnel to be briefed on the rules, issues, and history of this litigation, and it would allow them to provide meaningful input on the parties’ discussions regarding the briefing schedule and format.”  On April 7, 2017, EPA filed a motion to hold the case in abeyance in light of its review of the rule (discussed below), which the Court granted.  As of March 2021 the case continues to be held in abeyance.

Petroleum Refineries

Section 111(b) of the Clean Air Act requires EPA to set new source performance standards (NSPS) for new and modified stationary sources of emissions that cause or contribute significantly to air pollution that may reasonably be anticipated to endanger public health or welfare. The NSPS must be based on the “degree of emissions limitation achievable through the application of the best system of emission reduction [BSER] which . . . the Administrator determines has been adequately demonstrated.” 42 U.S.C. § 7411(a)(1).

Once NSPS are established for a particular type of stationary source, EPA must (with limited exception) then adopt emissions guidelines to regulate existing sources of the same type under section 111(d) of the Clean Air Act.  42 U.S.C. § 7411(d). The emissions guidelines are typically implemented by states, which must develop, and have approved by EPA, plans for controlling emissions from existing facilities in the source category. If a state fails to develop a plan, or the state plan is not approved by EPA, a federal plan will apply.

Obama Administration (2009-2016)

On November 21, 2011, EPA announced that it would not meet the December 10 deadline for issuing proposed rules and was in negotiations to set a new deadline.

In December 2010, the EPA entered into a settlement agreement in New York v. EPA which it agreed to develop rules to control greenhouse gas emissions from petroleum refineries. Under the terms of the agreement, EPA was to issue proposed NSPS and emissions guidelines for new and existing refineries by December 10, 2011 and final regulations by November 10, 2012.

Municipal Landfills

Section 111(b) of the Clean Air Act requires EPA to set new source performance standards (NSPS) for new and modified stationary sources of emissions that cause or contribute significantly to air pollution that may reasonably be anticipated to endanger public health or welfare. The NSPS must be based on the “degree of emissions limitation achievable through the application of the best system of emission reduction [BSER] which . . . the Administrator determines has been adequately demonstrated.” 42 U.S.C. § 7411(a)(1).

Once NSPS are established for a particular type of stationary source, EPA must (with limited exception) then adopt emissions guidelines to regulate existing sources of the same type under section 111(d) of the Clean Air Act.  42 U.S.C. § 7411(d). The emissions guidelines are typically implemented by states, which must develop, and have approved by EPA, plans for controlling emissions from existing facilities in the source category. If a state fails to develop a plan, or the state plan is not approved by EPA, a federal plan will apply.

On May 10, 2021, EPA issued federal plan requirements for existing municipal solid waste landfills operated by any state, tribe or locality that has not submitted a satisfactory plan to reduce emissions of landfill gas in accordance with the 2016 Municipal Solid Waste Landfills Emission Guidelines. 86 Fed. Reg. 27,756 (May 21, 2021).

Biden Administration (2021-2024)

On May 10, 2021, EPA issued federal plan requirements for existing municipal solid waste landfills operated by any state, tribe or locality that has not submitted a satisfactory plan to reduce emissions of landfill gas in accordance with the 2016 Municipal Solid Waste Landfills Emission Guidelines. 86 Fed. Reg. 27,756 (May 21, 2021).

First Trump Administration (2017-2020)

On August 26, 2019, EPA published a final rule to amend the methane emissions guidelines for existing municipal landfills, and postpone the due date for state plans promulgated pursuant to those guidelines. 84 Fed. Reg. 44,547 (Aug. 26, 2019). (See Environmental Defense Fund v. EPA in “Litigation” below.)

On May 5, 2017, EPA had announced that it would reconsider certain provisions of two rules establishing methane emissions standards for new and existing landfills. On May 31, 2017, EPA published a 90-day administrative stay of the two rules, pending their reconsideration pursuant to Executive Order 13783. (See NRDC v. Pruitt in “Litigation” below.) EPA published the proposed rule to amend the methane emissions guidelines for existing municipal landfills on October 30, 2018. 83 Fed. Reg. 54,527 (Oct. 30, 2018).

Obama Administration (2009-2016)

On August 29, 2016, EPA published final NSPS for methane emissions from new, modified, and reconstructed municipal solid waste landfills. 81 Fed. Reg. 59,332 (Aug. 29, 2016). In a separate rule, EPA issued emission guidelines for existing facilities. 81 Fed. Reg. 59,276 (Aug. 29, 2016).

Litigation

Challenge to 2017 Stay - NRDC v. Pruitt

On June 16, 2017, the Natural Resources Defense Council, Clean Air Council, Clean Wisconsin, and Conservation Law Foundation filed a petition for review, challenging EPA’s decision to stay the landfill methane standards.  On January 31, 2018, petitioners voluntarily dismissed the case, explaining that the stay period had passed, and no new or existing landfills appeared to have been affected.

Challenge to 2019 Rule - Environmental Defense Fund v. EPA

The EPA rule postponing the due date for state plans was challenged by environmental groups on October 23, 2019 and by a coalition of states on October 25, 2019. On April 5, 2021, the court granted a request by EPA to vacate the rule.