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Md., Other States Push EPA to Force Stricter Pollution Standards for Pa. Power Plants

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An advisory commission of 13 Northeastern states has approved a recommendation to the Environmental Protection Agency that Pennsylvania’s power plants, whose emissions have been a major source of ozone and air pollution in Maryland, must add more pollution control measures.

The regional Ozone Transport Commission voted 9-2 on June 3 to send Maryland’s petition to the EPA. Pennsylvania and Virginia voted no, while New York and Maine abstained.

“This sends a very strong and timely message that the Clean Air Act needs to be enforced and that we all need to benefit from that,” said Maryland Environment Secretary Ben Grumbles.

Ground-level ozone is a major pollutant. On a hot day, nitrogen oxides (NOx) and volatile organic compounds react and create ground-level ozone, or smog. This makes the air difficult to breathe, especially for people with underlying respiratory diseases like asthma.

Maryland Environment Secretary Ben Grumbles

Up to 70% of ozone and air pollution in Maryland comes from an upwind state, according to a 2020 report on air by Maryland Department of the Environment. Transported air pollution and ozone from upwind states makes it hard for downwind states, like Maryland, to meet federal standards for air quality.

Air pollution from cars, power plants and factories can be carried by the wind and travel long distances, frequently across states.

A section of the Clean Air Act allows any state in the OTC to petition and recommend additional control measures for all or some states. This is the second time in history that OTC approved a petition to target pollution from another state — the route Maryland took to target pollution from Pennsylvania power plants.

And it’s not the first time that Maryland has asked the EPA to intervene to address Pennsylvania pollution. Last month, Maryland, Virginia and the District of Columbia announced their intention to sue EPA to get the federal agency to force Pennsylvania and New York to meet water pollution standards set by the federal Chesapeake Bay Watershed Agreement of 2014.

Pennsylvania coal plants

After analyzing excess emissions in 2017-2018, Maryland concluded that much of the state’s air pollution problems came from Pennsylvania’s coal-fired power plants, which had not been running their pollution controls every day of the ozone season.

In May 2019, the Maryland Department of the Environment submitted a petition to the OTC, asking the regional agency to recommend the EPA to require Pennsylvania coal plants to run their existing control equipment every day during the summer months, when smog is at its worst.

When EPA conducted ozone transport modeling for 2008 and 2015 ozone standards, it showed that Pennsylvania was the most significant contributor to Maryland’s air pollution.

If Pennsylvania power plants ran their existing pollution controls every day, they would reduce up to 47 tons of excess nitrogen oxide emissions, according to Jay Apperson, a spokesman for MDE. Such a reduction would allow Maryland to meet the current federal air quality standard for ozone.

“The Chesapeake Bay ecosystem will benefit as well,” Grumbles said, because about a third of nitrogen oxide pollution that enters into the Chesapeake Bay is atmospheric.

However, the Pennsylvania Chamber of Business and Industry questioned Maryland’s claim that Pennsylvania’s coal plants were the main culprit of Maryland’s air pollution problems. Pennsylvania did not exceed federal ozone standards recorded on 23 of the 50 days that Maryland’s levels did, according to the business group. This suggests that there may have been no correlation between Pennsylvania’s emissions and the excess of ozone that Maryland had measured, said Kevin Sunday, the Director of Government Affairs at the Pennsylvania Chamber.

Maryland is a significant importer of power from other states — not just the Pennsylvania coal plants that Maryland is targeting with its petition, Sunday said.

The Pennsylvania Department of Environmental Protection is currently updating and improving its regulations, called RACT III, which would require coal-fired power plants to meet daily ozone limits during the summer season. These updates must go into effect no later than 2023.

“Pennsylvania is in compliance with EPA requirements regarding the ozone transport region petition,” Neil Shander, a spokesman for Pennsylvania DEP said. “The information used in the OTC petition is dated and was determined by both EPA and federal courts to be unsuitable for measuring the current status of Pennsylvania’s efforts to reduce air pollution.”

Grumbles acknowledges that Pennsylvania is making progress.

“I am encouraged by Pennsylvania’s commitment to move forward with the regulations that they started at the state level,” he said. “It’s all about driving positive change and cleaner air at those Pennsylvania coal plants.”

Grumbles argued the petition is necessary because in the event that Pennsylvania does not finalize its new regulations, Maryland will have its request to EPA on record — as a way to ensure federal oversight and accountability over Pennsylvania’s coal plants.

Next steps for the petition

EPA received the petition on June 8 and has 90 days to hold a public hearing at the federal level, Grumbles said. Then, EPA has up to nine months to make a final decision.

Maryland and other members of the Ozone Transport Commission could sue the EPA if federal officials deny the petition. This would not be the first time that Maryland has sued EPA for denial of a petition under the Clean Air Act, however.

One section of the Clean Air Act gives a state the authority to ask EPA to set emission limits for specific sources of air pollution from other states. In 2016, Maryland submitted a similar petition, asking EPA to require 19 power plants from five upwind states to run their pollution controls every day during the summer ozone season. When EPA denied this request in 2018, Maryland sued.

If EPA approves Maryland’s petition, the federal agency will be responsible for requiring Pennsylvania to revise its state plan to include approved additional control measures within one year after EPA’s ratification of the recommendations. Pennsylvania would be responsible for making sure that each power plant runs pollution controls every day.

However, Sunday from the PA Chamber does not think the petition is necessary. By the time EPA makes a decision, he said, Pennsylvania would have already addressed excess emissions from coal plants through its new state regulations, RACT III. There are only six coal plants left in Pennsylvania, and marketplace dynamics will probably further reduce or completely eliminate the operations of these coal facilities in the near future as well, Sunday said.

But Grumbles believes Maryland’s argument to the EPA is “compelling,” and that the state will prevail with its bureaucratic maneuver.

“Science that shows that air quality benefits occur when controls are run every day during the hot summer is compelling,” he said. “We are committed to working with Pennsylvania, but we are also committed like other states in OTC to the enforcement of the Clean Air Act.”

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Md., Other States Push EPA to Force Stricter Pollution Standards for Pa. Power Plants