Maryland has joined several other Northeastern states in suing the U.S. Environmental Protection Agency in an effort to hold other states accountable for pollution that blows into the region, creating hazardous summertime smog.

“Interstate smog doesn’t respect political boundaries, so we need more action by upwind states and the EPA to protect our citizens and level the playing field for our businesses,” said Ben Grumbles, Maryland’s environment secretary.

Maryland and other Northeastern states have been trying since 2013 to add more states to a group known as the Ozone Transport Region, which coordinates efforts to reduce air pollution. They formally petitioned the EPA to require nine “upwind” states — Illinois, Indiana, Kentucky, Michigan, North Carolina, Ohio, Tennessee, Virginia and West Virginia — to join the interstate group.

The agency was slow to act on the request during President Barack Obama’s tenure, spurring some of the states to file a lawsuit to force it to make a decision. The final decision came last month from President Donald J. Trump’s EPA, denying the expansion of the ozone region.

“We were disappointed by the decision, but not surprised,” said Grumbles, who chairs the commission that oversees the ozone region.

Maryland and seven other states — Connecticut, Delaware, Massachusetts, New York, Pennsylvania, Rhode Island and Vermont — filed a lawsuit last week appealing the decision in a federal appeals court in Washington.

“The federal government has a fundamental responsibility to act,” New York Attorney General Eric T. Schneiderman said in a statement announcing the lawsuit. “Yet the Trump EPA has abandoned its responsibilities — repeatedly failing to act to control smog pollution that jeopardizes New Yorkers’ health. Attorneys general will continue to act to protect those we serve.”

An EPA spokesman declined to comment on the lawsuit.

When the EPA made its decision not to expand the ozone region official in November, the agency said there are other ways under the Clean Air Act to reduce air pollution in the additional states.

“The EPA believes that other CAA provisions … provide a better pathway for states and the EPA to develop a tailored remedy that is most effective for addressing any remaining air quality problems” in the other states, the agency wrote.

Maryland environmental officials estimate that up to 70 percent of the air pollution here blows in from other states. That includes ground-level ozone, also known as smog, which is created when summertime heat and sunlight react with emissions from cars, factories and power plants, causing breathing difficulties and worsening heart and lung diseases.

Maryland Attorney General Brian E. Frosh said the EPA’s decision not to expand the ozone region is another example of EPA Administrator Scott Pruitt’s favoring businesses over the health of people who must breathe polluted air.

“They’re interested only in the health of businesses that unfortunately are causing the pollution. They are only looking at one side of the equation,” said Frosh, a Democrat. “They are violating the law. They don’t respect the rule of law.”

Frosh said Maryland has no choice but to file lawsuits to compel the EPA to enforce existing laws such as the Clean Air Act.

“Unless the EPA enforces the Clean Air Act all over the country, Maryland will be suffering from pollution generated outside our borders, over which we have no control,” he said.

Frosh and Grumbles both noted that Maryland has taken significant steps to reduce pollution generated in the state, including requiring emissions reductions at Maryland’s power plants.

“Our goal has been to continue to put pressure on upwind states and on ourselves to reduce ozone, whether it’s from a stationary source like a power plant or from a mobile source like a car or truck,” said Grumbles, who reports to Republican Gov. Larry Hogan.

The Ozone Transport Region currently includes 11 states — Maryland, Connecticut, Delaware, Maine, Massachusetts, New Hampshire, New Jersey, New York, Pennsylvania, Rhode Island, Vermont — and the Washington metro area.

Josh Tulkin, executive director of the Maryland Sierra Club, said he’s encouraged to see states working together “to make up for where the EPA is currently failing.”

“We’re excited to see Maryland and the other states move forward,” he said. “Several other states are blowing pollution into Maryland, and Maryland also has its own pollution to deal with.”

This isn’t the first action by Maryland trying to get the federal government to compel other states to reduce pollution that affects Maryland. Last year, Grumbles petitioned the EPA to require that 19 power plants in five states run certain pollution-reduction controls all summer long to reduce pollution that reaches Maryland.

“We’re not asking for anything we haven’t already done with Maryland’s coal power plants,” Grumbles said.

The EPA hasn’t responded to the request or held any public hearings, and that request is now tied up in court, too, Grumbles said.

Frosh has taken several actions against the Trump administration on environmental issues, particularly after state lawmakers granted him the authority to file lawsuits against the federal government without needing the governor’s support.

Under Frosh’s direction this year, the state has taken actions on more than half a dozen environmental issues before the federal government. They range from filing a lawsuit over a delay in assessing stiffer fines to automakers who violate fuel-efficiency standards to laying the groundwork for a possible lawsuit over how wetlands are defined.

Frosh also has taken steps to support the Clean Power Plan, an Obama-era program to reduce pollution from power plants.

When Pruittwas Oklahoma’s attorney general, he sued to block the Clean Power Plan, and Maryland joined the case in support of the plan. While that lawsuit is tied up in court, the EPA has started to take steps to repeal the plan.

Frosh and General Assembly leaders announced Thursday that they plan to hold their own hearing in Annapolis on the repeal of the Clean Power Plan, after the EPA didn’t schedule any of its “public listening sessions” on the issue in this area. The EPA held two hearings in Charleston, W.Va., last month and is planning more in California, Wyoming and Missouri.

The Maryland hearing is planned for 1 p.m. on Jan. 11 in the Legislative Services Building in Annapolis.

pwood@baltsun.com

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