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Once In Always In Guidance for Major Sources under the Clean Air Act

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Quick Take

In January 2021, President Biden issued an executive order requiring EPA to review the Trump-era rule that allowed “major sources” that meet a certain hazardous air pollutant (HAP) emission threshold to be reclassified to no longer require stringent technologies. Environmental NGOs challenged this rule, and in February 2022, the DC Circuit granted EPA’s unopposed motion to hold the case in abeyance until Fall 2022 as EPA continued its review of the rule and considers promulgating a replacement rule. On September 21, 2023 EPA proposed a rule to refine “major source” review under the NESHAP program, proposing to allow major sources that limit emissions to reclassify as “area sources” but to also impose emission limitation safeguards on those sources. Comments are due by November 13, 2023.

Why it Matters

As part of the Clean Air Act (CAA), EPA regulates HAPs. HAPs include benzene, metals, and other pollutants that are known to cause cancer and other serious health effects. A facility is considered a major source if it has the potential to emit 10 tons per year of any one HAP or 25 tons per year of any combination of HAPs. All other facilities are considered area sources. Major sources (such as power plants and petroleum refineries) are subject to Maximum Achievable Control Technology (MACT) standards, which are stringent pollution control requirements based on the technology used in the best-controlled sources in the industry.

MACT standards significantly limit hazardous air pollutants, often reducing emissions to below the major source thresholds of 10 and 25 tons per year. For many years EPA’s policy has been that a major source remains a major source even after MACT is applied and it reduces its emissions. Sources must continue to operate under the more stringent requirements and maintain MACT-level low emissions.

A different approach – allowing the source to reclassify as an area source after it reduces its emissions below the threshold – would replace the source’s initial MACT requirements with less stringent requirements but could result in a large increase in pollution. After first applying the MACT, the source could switch to less effective pollution controls, or operate its controls less frequently or at lower removal efficiencies and release more HAPs up to the major source threshold amounts. This increase could have significant health effects on local communities, especially those that are located near major sources of toxic air pollutants.

Allowing a major source to stop operating with stringent controls would be counter to the primary goal of the Clean Air Act of protecting public health and the environment by minimizing emissions consistent with standards such as MACT-based ones.

Current Status

On Jan. 25, 2018, EPA issued guidance withdrawing the “Once In, Always In” policy and weakening the pollution control technology requirements for major sources of HAPs. On Oct. 1, 2020, EPA released a final rule replacing the “Once In, Always In” policy that allows major sources of HAPS to reclassify to area sources, making them subject to less stringent emissions control and compliance requirements. According to EPA, the rule could increase HAP emissions between 919 to 1,258 tons per year. Multiple groups have sued EPA challenging the final rule. On his first day in office, President Biden issued an Executive Order requiring EPA to review the final rule replacing the “Once In, Always In” policy. According to the administration’s Unified Agenda, EPA planned to issue a proposed rule by December 2021, and a final rule by December 2022 but on February 28, 2022 a federal judge granted EPA’s unopposed motion to hold a case in abeyance until Fall 2022, when it intends to revise or rescind the rule. On September 21, 2023 EPA proposed a rule to refine “major source” review under the NESHAP program, proposing to allow major sources that limit emissions to reclassify as “area sources” but to also impose emission limitation safeguards on those sources.

Timeline of Events

HISTORY
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In May 1995, The Environmental Protection Agency (EPA) issued “once in, always in” guidance for major sources under the Clean Air Act (CAA). This guidance declared that, after the first Maximum Achievable Control Technology (MACT) standard compliance date, a major source could not be reclassified and would always be required to limit its Hazardous Air Pollutants (HAPs) emissions through MACT.

In 2007, EPA proposed a rule to replace the “Once In, Always In” guidance. EPA did not finalize this rule.

TRUMP ADMINISTRATION
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Jan. 25, 2018 EPA issues a guidance memorandum withdrawing the “Once In, Always In” policy. This new guidance establishes that, at any time, “a major source which takes an enforceable limit on its potential to emit and takes measures to bring its HAP emissions below the applicable threshold” may be reclassified and no longer be required to use MACT. The guidance is published in the Federal Register on Feb. 8, 2018.

March 26, 2018 A coalition of environmental groups sues EPA in the D.C. Circuit over the guidance memo that weakens regulation of HAPs.

April 9, 2018 California sues EPA as well. The court later consolidates the cases as California Communities Against Toxics, et al v. EPA, Docket No. 18-1085.

Dec. 21, 2018 EPA states in its brief in California Communities Against Toxics v. EPA that the agency intends to conduct a notice and comment rulemaking to formalize the “Once In, Always In” guidance.

July 26, 2019 EPA publishes a proposed rule to replace the “Once In, Always In” policy it withdrew in January 2018. This proposal formalizes the Jan. 2018 memo that allows a major source that falls below HAP emissions thresholds to reclassify and no longer use MACT.

Aug. 20, 2019 The D.C. Circuit finds that the January 2018 memo is not a final agency action and dismisses the case. California Communities Against Toxics, et al v. EPA, Docket No. 18-1085.

Oct. 4, 2019 California and environmental groups submit a petition for rehearing to the D.C. Circuit in California Communities Against Toxics, et al v. EPA, Docket No. 18-1085.

Jan. 22, 2020 The D.C. Circuit denies the petition for rehearingCalifornia Communities Against Toxics, et al v. EPA, Docket No. 18-1085.

Oct. 1, 2020 EPA releases the final rule replacing the “Once In, Always In” policy. The final rule allows major sources of HAPs to reclassify to area sources, making them subject to less stringent emissions control and compliance requirements. According to EPA’s emissions impact analysis, the rule could increase HAP emissions between 919 to 1,258 tons per year. EPA publishes the final rule replacing the “Once In, Always In” policy in the Federal Register on Nov. 19, 2020; it will become effective 60 days later.

Jan. 15, 2021 Environmental groups file suit challenging the final ruleCalifornia Communities Against Toxics, et al. v. EPA, No. 20-1024 (DC Cir.).

Jan. 18, 2021 A coalition of environmental groups files a petition for reconsideration with EPA, arguing the final rule is arbitrary and capricious and that EPA acted unlawfully by removing existing regulatory requirements without public comment. The groups ask EPA to stay the rule for 90 days, withdraw the rule, and immediately withdraw associated guidance.

Jan. 19, 2021 A coalition of states file suit against EPA over the final ruleState of California, et al. v. EPA, No. 21-1034 (DC Cir.).

biden ADMINISTRATION
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Jan. 20, 2021 President Biden issues an Executive Order requiring EPA to review the final rule replacing the “Once In, Always In” policy.

June 11, 2021 According to the Unified Agenda, EPA plans to issue a proposed rule to suspend, revise, or rescind the Trump administration’s replacement of the Once In, Always In policy by December 2021, and release a final rule by December 2022.

Feb. 18, 2022 EPA files an uncontested motion in State of California, et al. v. EPA, No. 21-01034 (DC Cir.), requesting the D.C. Circuit to hold the case in abeyance until September 19, 2022. EPA explains that it is reviewing the Reclassification Rule and needs additional time to determine whether it will revise or rescind the rule, obviating the need for judicial resolution. The court grants EPA’s motion on Feb. 28, 2022 and requires EPA to file an interim status report by June 21, 2022 and parties to file motions to govern further proceedings by September 19, 2022.

July 17, 2023 EPA sends a draft proposal reconsidering President Trump’s revocation of the “once in, always in” policy to the White House Office of Management and Budget (OMB) for inter-agency review.

Sept. 21, 2023 EPA proposed a rule to refine “major source” review under the NESHAP program, proposing to allow major sources that limit emissions to reclassify as “area sources” but to also impose emission limitation safeguards on those sources. Comments are due by November 13, 2023.