Indiana is one of nearly two dozen states affected by a new U.S. Environmental Protection Agency rule limiting the air pollution that travels from those states and degrades the air quality in states downwind.
Under the Clean Air Act, the EPA must establish emission standards, known as National Ambient Air Quality Standards, for several harmful air pollutants, known as “criteria pollutants.”
The CAA contains a “good neighbor” provision that requires the EPA to prohibit states from emitting pollution in amounts that could affect air quality in other states and prevent them from attaining and maintaining pollutant standards.
The Biden administration’s updated “good neighbor” rule will further limit nitrogen oxide pollution from power plants and factories that produce cement, steel, iron, glass, petroleum and coal products in 23 states, including Indiana, in order to reduce their impact on the ozone levels in downwind states.
According to the EPA, emissions from these 23 states have worsened the air quality of multiple other states, causing them to violate the 2015 Ozone National Ambient Air Quality Standards.
Ground level ozone is created by chemical reactions that happen when nitrogen oxides mix with volatile organic compounds in heat and sunlight.
Higher ozone levels can cause coughing and sore throats, can make it difficult to breathe deeply and can cause pain when taking a deep breath. Ozone can also worsen existing health problems, like asthma, emphysema and chronic bronchitis.
The rule sets yearly limits, called budgets, for the amount of nitrogen oxides emitted by facilities in designated states.
Under the rule, the state of Indiana could reduce its nitrogen oxide pollution by nearly half by 2029.
“Every community deserves fresh air to breathe. EPA’s ‘Good Neighbor’ plan will lock in significant pollution reductions to ensure cleaner air and deliver public health protections for those who’ve suffered far too long from air quality-related impacts and illness,” said EPA administrator Michael Regan. “We know air pollution doesn’t stop at the state line. Today’s action will help our state partners meet stronger air quality health standards beyond borders, saving lives and improving public health in impacted communities across the United States.”
Indiana provided the fourth-largest contribution to downwind 2015 ozone standard nonattainment. Only California, New York and Illinois contributed more to helping make downwind air pollution worse.
The EPA projects that in 2026 alone the rule will help prevent about 1,300 premature deaths and 2,300 hospital and emergency rule visits. The agency said the rule could cut asthma symptoms cases by 1.3 million, help avoid 430,000 school absence days and avoid 25,000 lost work days.
“For years, states have failed to live up to their ‘Good Neighbor’ obligations,” said Earthjustice attorney Kathleen Riley. “We are pleased that EPA has responded to calls from overburdened communities to require pollution reductions from industrial sources in addition to power plants and to ensure the largest coal-fired power plants run their pollution controls every day of the ozone season. Communities across the country have too long suffered from harmful smog pollution originating in upwind states.”
Several electric utilities serving Indiana and their trade organizations, including the Northern Indiana Public Service Co., American Electric Power Company Inc., Ohio Valley Electric Corp., Indiana Energy Association and the Indiana Municipal Power Agency, have come out against the rule in comments to the EPA.
The rule will come into effect later this year and will most likely face legal challenges.
In 2019, a federal court ruled in favor of downwind states that sued after the Trump administration did not set timeframes for states to implement the rule.