04/23/2018 - Regulatory Rollback

Regional Haze Rule

by EELP Staff

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Why it Matters

Haze occurs when small particles of air pollution scatter and absorb sunlight, blurring scenic views and decreasing the distance that can be seen from overlooks. In response to this problem, Congress enacted Section 169A of the Clean Air Act to protect visibility in national parks and wilderness areas. The Environmental Protection Agency (EPA) subsequently promulgated the Regional Haze Rule in 1999. The program directs states to implement pollution control plans to improve visibility and air quality at national parks, such as the Grand Canyon. 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.

In addition to the benefits for visitors at national parks, the regional haze program delivers public health benefits. 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. Implementation of the Regional Haze Rule and associated regulations has produced sharp declines in the emissions of those pollutants, resulting in improved air quality as well as improved visibility in scenic areas. In fact, 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.

Current Status

The Obama administration updated and strengthened the Regional Haze Rule on December 14, 2016. Texas challenged the rule, and a number of states, industry, and environmental groups joined the suit on both sides. On January 17, 2018, EPA decided to revisit the rule. On September 10, 2018, EPA released a Regional Haze Rule reform roadmap, indicating its intent to devolve more regulatory authority to the states.

Overview of the Regional Haze Program

The Regional Haze Rule requires that states develop and implement comprehensive plans to reduce human-caused regional haze in designated areas. States also must calculate and work towards 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 – which could include the National Park Service, the U.S. Forest Service, the Bureau of Land Management, and others.

Substantively, the Clean Air Act and the Regional Haze Rule mandate that certain older polluting facilities, like power plants, adopt pollution abatement technology that is determined to be the “Best Available Retrofit Technology.” Similarly, if a federal land manager certifies that visibility impairment is reasonably attributed to a specific facility’s emissions, the state is required to assess the facility and determine whether it should install and operate Best Available Retrofit Technology.

The first state plans were due 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.

Separate from the Regional Haze program, other Clean Air Act programs aim to curb the interstate air pollution that can lead to visibility concerns.  One key program is the Cross-State Air Pollution Rule (CSAPR), which is an interstate emissions trading program that regulates SO2 and NOx emissions from power plants across a large portion of the country to prevent pollution in one state from adversely affecting air quality in another state.


May 30, 2012 EPA issues a rule allowing states to include certain older power plants that emit haze-causing pollutants in a state’s CSAPR plan. If the state chooses to regulate the facility under CSAPR, the facility would meet its requirements under the Regional Haze Rule and thus not need to install Best Available Retrofit Technology pollution controls. There is ongoing litigation regarding the legality of this final rule, Utility Air Regulatory Group v. EPA, No. 12-1342. Oral argument was held in the U.S. Court of Appeals for the D.C. Circuit on Nov. 16, 2017.

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. After an extension to the comment period, comments are due on Aug. 10, 2016.

Dec. 14, 2016 EPA issues a final rule with an effective date of Jan. 10, 2017. The rule 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’ long-term and reasonable 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 Era

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

March 10, 2017 The State of Alaska, the Utility Air Regulatory Group (UARG), and the Chamber of Commerce file separate petitions for review of the final rule, Nos. 17-1074, 17-1075, 17-1076 respectively.

March 13, 2017 The State of North Dakota, No. 17-1080, the State of Arkansas, No. 17-1079, National Parks Conservation Association and a coalition of environmental groups, No. 17-1078, as well as four additional industry representatives, Nos. 17-1077, 17-1082, 17-1083, 17-1084, file petitions for review. In addition, industry groups and UARG send letters to EPA directly, petitioning the agency to reconsider the rule.

March 15, 2017 The court consolidates the 11 cases as State of Texas, et al v. EPA, et al, No. 17-1021 (D.C. Cir.).

March 24, 2017 The State of Alaska petitions EPA to reconsider and stay the rule, citing provisions regarding the impact of international air emissions on states’ visibility goals.

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.

May 16, 2017 EPA files an unopposed motion to delay the case. EPA files, and the court grants, similar motions on July 18, 2017, Sep. 15, 2017, and Dec. 15, 2017.

Jan. 17, 2018 EPA responds to the three petition letters and announces its decision to review the final rule, including the federal land manager consultation requirements and the provisions related to the determination that regional haze is reasonably attributed to a particular source. EPA also announces that it plans to finalize additional guidance documents for the state plans that are due in 2021.

Jan. 19, 2018 EPA files a motion to hold the case in abeyance pending its review of the final rule. Environmental groups support this motion.

Jan. 30, 2018 The court grants EPA’s motion to hold the case in abeyance.

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

Sep. 10, 2018 Acting Administrator of the EPA Andrew Wheeler announces EPA’s new Regional Haze Reform Roadmap. The Roadmap prioritizes giving more power to the states to determine emissions controls and relying on other Clean Air Act programs to improve visibility. A memo to staff indicated that EPA is developing a rulemaking to modify portions of the Regional Haze Rule.

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.