Regional Haze Rule - Harvard Law School

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Quick Take

After superseding Trump-era guidance that gave states significant discretion to determine appropriate regional haze compliance measures, EPA missed the July 31, 2021 deadline to review states’ regional haze state implementation plans (SIPs). A coalition of environmental groups is pursuing litigation against the agency for failing to enforce recent deadlines for SIP submissions. On August 30, 2022 EPA issued its “findings of failure to submit” adequate regional haze SIPs, which starts the two-year clock for states to revise those SIPs or for EPA to issue federal implementation plans (FIPs).

Why it Matters

Congress enacted Section 169A of the Clean Air Act to decrease haze and protect visibility in national parks and wilderness areas. The primary pollutants that cause regional haze, including particulate matter, nitrogen oxides (NOx), sulfur dioxide (SO²), and volatile organic compounds (VOCs), are linked to serious health effects including premature death. Some of these pollutants also contribute to acid rain.

The Environmental Protection Agency (EPA) promulgated the Regional Haze Rule in 1999, directing states to implement pollution control plans to improve visibility and air quality at national parks. States must also work toward interim, short-term progress goals, with a long-term goal of returning targeted areas to their natural visibility conditions by 2064. States have an obligation to consult with the relevant federal land managers during the plan development process. Since the implementation of the regional haze program, the average visual range has increased from 90 to 120 miles in some western parks and from 50 to 70 miles in some eastern parks.

EPA estimates that during the first implementation period (2007-2018), there was a reduction in SO₂ emissions of 500,000 tons per year and in NOx emissions of 300,000 tons per year. These reductions have resulted from the requirement that certain older polluting facilities, like power plants, adopt pollution abatement technology that is determined to be the Best Available Retrofit Technology (BART). EPA allows this technology requirement to be met through a variety of methods including installing and operating specific technology, like scrubbers; requiring that sections of the facility periodically shut down to decrease overall annual emissions, known as “seasonal curtailment;” or integrating the power plants into the interstate emissions trading program such as the Cross-State Air Pollution Rule.

The first state regional haze plans were due to EPA in 2007. Progress reports are required every 5 years and plan revisions are required every decade, with the first full revision originally due by 2018. If states fail to submit a satisfactory plan, EPA is required to develop a federal plan for the state. At the close of the Trump Administration, EPA was in the final stages of implementing an April 12, 2018 presidential directive to review all existing FIPs and to develop options to replace those plans with SIPs.

EPA is also involved in ongoing litigation with multiple states and regulated industries regarding the adequacy of the states’ SIPs and the consequent FIPs that EPA promulgated. In many cases, the litigation and the FIP involve only a portion of the state’s plan, including pollution controls for specific power plants.

Current Status

On September 10, 2018, the Trump Administration released a Regional Haze Rule reform roadmap, which prioritizes states’ determining emissions controls and relying on other Clean Air Act programs to improve visibility. Now, under the Biden administration, EPA will review SIPs, which were due July 31, 2021, consistent with guidance EPA released on July 8, 2021.

On April 13, 2022, a coalition of environmental groups sued EPA for failing to enforce a July 2021 deadline for states to submit regional haze implementation plans; litigation is ongoing. On August 30, 2022 EPA issued its “findings of failure to submit” adequate regional haze SIPs, which starts the two-year clock for states to revise those SIPs or for EPA to issue FIPs.

Timeline of Events

obama administration

May 30, 2012 EPA issues a rule allowing states to include certain older power plants that emit haze-causing pollutants in a their CSAPR plan, in which case the facility would meet its requirements under the Regional Haze Rule and not need to install Best Available Retrofit Technology pollution controls.

May 4, 2016 EPA issues a separate proposed rule to strengthen the Regional Haze Rule by updating and amending the requirements for state plans, Protection of Visibility: Amendments to Requirements for State Plans.

Dec. 14, 2016 EPA issues a final rule that includes a number of significant technical, measurement, and definitional changes to the Regional Haze Rule. It also includes a proposal to enhance the federal land manager consultation requirements and to better integrate states’ progress goals for visibility. The rule extends the next deadline for state implementation plans from 2018 to July 31, 2021.

Jan. 18, 2017 The State of Texas petitions the U.S. Court of Appeals for the D.C. Circuit to review the Dec. 14, 2016 final rule. No. 17-1021.

Trump administration

Feb. 22, 2017 The National Parks Conservation Association and the Sierra Club move to intervene in Texas’ case on behalf of EPA.

March 10-24, 2017 Alaska, Arkansas, North Dakota, the Utility Air Regulatory Group (UARG), the Chamber of Commerce, the National Parks Conservation Association, a coalition of environmental groups, and four industry representatives file separate petitions for review of the final rule. The court consolidates the 11 cases as State of Texas, et al v. EPA, et al, No. 17-1021 (D.C. Cir.). Industry groups, UARG, and Alaska also send letters to EPA directly, petitioning the agency to reconsider the rule.

April 12, 2017 UARG files a motion to intervene on behalf of EPA in the environmental groups’ challenge to the rule, No. 17-1078, consolidated with No. 17-1021.

Jan. 17-30, 2018 EPA responds to the three petition letters and announces its decision to review the final rule. EPA also announces that it plans to finalize additional guidance documents for the state plans that are due in 2021. EPA files a motion to hold the case in abeyance pending its review of the final rule, which the court grants.

April 12, 2018 President Trump directs EPA to review EPA’s engagement with states as part of the regional haze program.

Sep. 10, 2018 EPA releases a Regional Haze Reform Roadmap, which prioritizes giving more power to the states to determine emissions controls and relying on other Clean Air Act programs to improve visibility.

Aug. 20, 2019 EPA releases guidance for state implementation plan development under the regional haze program. The guidance is intended to implement the 2018 Reform Roadmap by leaving emissions controls to other Clean Air Act programs and state emission control programs. Critics argue that this guidance allows states to simply ignore how pollution impacts visibility in parks and offers little advice on how to identify pollution sources for emission reduction analysis.

biden administration

July 8, 2021 EPA issues a guidance memo to regional directors regarding the second planning period for regional haze SIPs, and includes for the first time a section encouraging states to consider equity and environmental justice impacts when developing strategies.

Jan. 18, 2022 EPA proposes to disapprove Wyoming’s 2020 SIP revision, which would have required less stringent emission limits for Jim Bridger Units 1-4, including removing an obligation to install and operate SCR pollution control equipment on Units 1 and 2. Comments are due Feb. 17. 2022.

Feb. 7, 2022 A coalition of environmental NGOs files a notice of intent to sue EPA for its failure to issue a finding that 39 states did not submit SIPs as required by the Regional Haze rule by the July 31, 2021 deadline.

Apr. 7-13, 2022 EPA announces it will make findings that states failed to submit SIPs by August 31, 2022 and that states should submit SIPs before that date. However, NGOs file suit in the Northern District of California challenging EPA’s failure to take action against the 34 states that failed to submit regional haze SIPs by the January 31, 2022 deadline, arguing that EPA did not have authority to extend the deadline to August 31, 2022. Sierra Club, et al. v. EPA, Docket 22-cv-02302 (N.D. Cal.).

May 20, 2022 Plaintiffs in Sierra Club, et al. v. EPA file a motion for summary judgment, requesting that the court require that EPA determine whether the states failed to submit adequate regional haze SIPs within 30 days.

June 1, 2022 In Sierra Club, et al. v. EPA, a federal judge rejects the environmentalists’ petition seeking an expedited ruling, reasoning that their request would not result in significantly faster outcomes.

Aug. 30, 2022 EPA publishes its “findings of failure to submit” regional haze SIPs for fifteen states. This finding triggers a deadline for EPA to approve the states’ revised SIPs or promulgate FIPs within two years. While this decision was initially due in July 2021, EPA satisfied its April commitment to make these findings before August 31, 2022.

March 28, 2023 A coalition of environmental groups led by the Sierra Club file a notice of intent to sue EPA for its failure to take final action on SIP revisions submitted by eight states within one year of the SIP being deemed complete. Deadlines for EPA to take final action by approving or disapproving the states’ SIPs ranged between November 2021 and February 2023.

May 4, 2023 EPA proposed to affirm the continued validity of the Cross-State Air Pollution Rule (CSAPR) trading programs as an alternative for Best Available Retrofit Technology (BART). In doing so, EPA denies a petition for partial reconsideration submitted by environmental groups who objected to CSAPR as a BART alternative. At the same time EPA also proposed a rule to reduce sulfur emissions at six Texas facilities and disapprove of a portion of the Texas Regional Haze SIP that was originally submitted in 2009.

June 15, 2023 Environmental groups filed a lawsuit against EPA for failing to approve or disapprove the SIPs submitted by eight states. Sierra Club, et al. v. EPA, Docket 23-cv-01744 (D.D.C. June 15, 2023).

July 26, 2023 EPA proposed to disapprove portions of the Texas and Oklahoma Regional Haze SIPs that it previously disapproved of in 2016. EPA’s previous disapproval was subject to litigation.

Aug. 25, 2023 EPA proposed to approve Maryland’s Regional Haze SIP submitted in February 2022. Maryland is not one of the eight states whose SIPs are of concern in the Sierra Club suit filed earlier in 2023.

Nov. 10, 2023 Environmental groups amend their complaint in Sierra Club, et al. v. EPA, to expand suit to include additional states’ SIPs. Docket 23-cv-01744 (D.D.C. June 15, 2023).

Jan. 8 2024 The D.C. District Court granted the North Dakota Attorney General’s motion to intervene as defendant and Pacificorp, a power company, to intervene as plaintiff. North Dakota hopes to avoid a settlement that might affect approval requirements for its SIP. Docket 23-cv-01744 (D.D.C. June 15, 2023).