Press Release Mar 29, 2024

Proposed Haze Pollution Consent Decree Sets Schedule to Improve Visibility in National Parks and Wilderness Areas

"From Acadia to Joshua Tree, parks will continue to suffer from hazy skies and unhealthy air until EPA ensures their protection.” - Ulla Reeves, Interim Director, NPCA's Clean Air Program

WASHINGTON – In response to legal action by Earthjustice, Environment Integrity Project, the National Parks Conservation Association and Sierra Club, the Environmental Protection Agency published notice of a proposed consent decree that includes deadlines for the agency to take action on 33 states’ plans to reduce haze pollution that harms air quality in national parks and wilderness areas.

After over a decade of urging EPA and state agencies to protect clean air in and around public lands, the proposed consent decree represents a tangible, welcome step forward in fulfilling the Clean Air Act’s mandate to eliminate haze pollution in national parks and wilderness areas.

Haze, centered in the groups’ legal challenge, is a major concern for 98 percent of national parks in the United States. The same pollutants responsible for the widespread air pollution also harm public health, particularly in communities experiencing targeted, systemic racism from polluting industries. Air pollution from burning fossil fuels and other sources worsens community health, increases healthcare costs and harms nature and sensitive ecosystems on public lands.

EPA’s Regional Haze Rule was established to address air pollution from coal-fired power plants and industrial sources that harm visibility in designated national parks and wilderness areas, otherwise known as Class I areas. Under the Clean Air Act, states must submit and update plans detailing how they will comply with the Regional Haze Rule every ten years. EPA is required to approve or reject these State Implementation Plans (SIPs) within 18 months, but EPA has failed to act on Regional Haze SIPs submitted by 33 states.

In June 2023, the Sierra Club and the National Parks Conservation Association, represented by Earthjustice and Sierra Club’s Environmental Law Program, filed a lawsuit against EPA for the agency’s failure to issue decisions on the state SIPs. The consent decree, published in the Federal Register today, establishes a timeline for EPA to approve, deny, or partially approve the outstanding state plans at assigned dates between 2024 and 2026, beginning with Massachusetts. If EPA rejects a SIP, the agency must issue a Federal Implementation Plan (FIP) detailing how the state must address haze pollution.

Earthjustice, EIP, NPCA and Sierra Club, alongside communities relying on parks and wilderness areas for their livelihoods and health, continue to underscore the need for not only stronger protections against haze, but a stronger consideration of environmental justice factors.

This interactive dashboard shows where EPA will take action on Regional Haze plans and which coal plants contribute the most haze pollution. Sierra Club, with support from Bloomberg Philanthropies’ Beyond Carbon campaign, is working to retire all remaining U.S. coal plants, including the 149 plants within states on this list. To date, their efforts have secured the retirement of 381 of the nation’s 530 coal-fired power plants.

“While the Regional Haze Rule was created to return our country’s most iconic parks to their natural visibility, the same pollution that impairs views harms public health, especially in communities already overburdened by fossil fuel pollution,” said Sierra Club Beyond Coal Director Laurie Williams. “This settlement is a step forward for communities who have already waited years for action on smog and particulate matter pollution that harms lung function, worsens asthma attacks and puts sensitive groups at extreme risk. Now, every deadline in this settlement helps ensure EPA follows the laws established by Congress, disapproves of do-nothing plans and restores clean air to national parks and communities across the country.”

“We are pleased to finally have a schedule for action given EPA is long overdue in responding to these 33 state plans for haze,” said National Parks Conservation Association Clean Air Program Interim Director Ulla Reeves. “Every day we delay, parks and people breathe dirty, dangerous air. Many states have submitted terribly weak plans, and we need EPA to act swiftly to hold polluters accountable for emission reductions from park-polluting energy and industrial facilities. From Acadia to Joshua Tree, parks will continue to suffer from hazy skies and unhealthy air until EPA ensures their protection.”

“EPA must ensure that these 33 plans cut air pollution to protect the health of people downwind and to restore the views in America’s parks and wilderness areas,” said Earthjustice Senior Attorney Charles McPhedran.

The consent decree was published in the Federal Register and can be found here.

In chronological order of EPA’s deadline to issue determinations, the 33 states are: Massachusetts, Kansas, New York, Connecticut, New Hampshire, Delaware, Wisconsin, Georgia, North Carolina, Utah, Wyoming, West Virginia, Arizona, Ohio, Idaho, Michigan, Texas, California, Florida, Oregon, Colorado, Montana, South Carolina, South Dakota, Tennessee, North Dakota, Indiana, Washington, Hawaii, Nevada, Alaska, Arkansas and Oklahoma.


About Earthjustice: Earthjustice is the premier nonprofit environmental law organization. We wield the power of law and the strength of partnership to protect people’s health, to preserve magnificent places and wildlife, to advance clean energy, and to combat climate change. We are here because the earth needs a good lawyer.

About The Environmental Integrity Project: The Environmental Integrity Project is a nonprofit organization dedicated to protecting public health and our natural resources by holding polluters and government agencies accountable under the law, advocating for tough but fair environmental standards, and empowering communities fighting for clean air and clean water.

About the National Parks Conservation Association: Since 1919, the nonpartisan National Parks Conservation Association has been the leading voice in safeguarding our national parks. NPCA and its more than 1.6 million members and supporters work together to protect and preserve our nation’s most iconic and inspirational places for future generations. For more information, visit

About the Sierra Club: The Sierra Club is America’s largest and most influential grassroots environmental organization, with millions of members and supporters. In addition to protecting every person’s right to get outdoors and access the healing power of nature, the Sierra Club works to promote clean energy, safeguard the health of our communities, protect wildlife, and preserve our remaining wild places through grassroots activism, public education, lobbying, and legal action. For more information, visit

Read more from NPCA

  • Magazine Article

    Code Red

    Summer 2024 | By Katherine DeGroff

    NPCA’s latest report on national park pollution paints a dire picture.

  • Blog Post

    Clearing the Air in the Smokies

    May 2024 | By Kelsey Barnett-Fischels

    Great Smoky Mountains National Park is starting to win its decades-long fight against dangerous haze, adding hope to the park’s horizon. 

  • Blog Post

    FAQs: Air Quality in National Parks

    Mar 2024 | By Lam Ho, Linda Coutant

    NPCA has released its 2024 “Polluted Parks” report, showing 97% of national parks suffer from air pollution. Meanwhile, the Environmental Protection Agency recently strengthened its air quality standards, which will…