A common tern guards its nest on Eastern Egg Rock, Thursday, July 18, 2019, off the coast of Maine. Credit: Robert F. Bukaty / AP

The U.S. Supreme Court’s Thursday decision to limit the federal government’s ability to regulate pollution will hamper Maine’s ambitious long-term climate goals.

In a 6-3 vote on Thursday, the court’s conservative majority ruled for West Virginia in a case against the Environmental Protection Agency, finding the Clean Air Act that was championed by the late Maine Sen. Edmund Muskie does not allow broad ability to regulate power-plant emissions from power plants.

It has downstream effects for Maine’s ambitious climate plan under Gov. Janet Mills, which includes net-zero carbon emissions by 2045 and getting 100 percent of its electricity from renewable sources and increasing the share of electric vehicles in new passenger car sales to 100 percent by 2050.

While the state has already taken steps to put the plan into action, advocates who lobbied for it say those efforts can only go so far without federal intervention on emissions and underscores the importance of collective state action going forward.

“Air pollution doesn’t recognize state boundaries,” said Maureen Drouin, the executive director of Maine Conservation Voters.

States are able to enact stricter environmental regulations than the federal government, such as Maine having a stricter standard for “forever chemicals” in drinking water a year before the EPA recently determined no amount of exposure to the chemicals is safe.

Many states typically wait for the federal government to take action before imposing their own limits. Drouin said those efforts will become more important after the court’s ruling as waiting for congressional approval for regulations could slow the process down.

The decision was blasted by Gov. Janet Mills and Attorney General Aaron Frey, who said it would undermine the state’s efforts to reduce climate change effects. His office said it was still processing the ruling and any effects it could have on Maine’s environmental efforts.

“Despite this loss, my office remains committed to enforcing Maine’s environmental protection laws to their fullest extent and preserving our natural resources for future generations,” Frey said.

Congress has moved slowly on more aggressive climate action efforts recently. The Democrats leading the Senate missed a self-imposed Memorial Day deadline to find agreement with Sen. Joe Manchin, D-West Virginia, on President Joe Biden’s Build Back Better bill, which includes significant climate change investments. A budget reconciliation measure connected to the bill expires in September, with the party facing tough midterm elections.

The federal government’s ability to decisively set regulations has been critical to advancing environmental efforts, said Jack Shapiro, the climate and clean energy director for the Natural Resources Council of Maine. He pointed to the Androscoggin River, which used to be choked with noxious foam and fumes that were the impetus for Muskie’s Clean Water Act as well.

“We can’t take any tools out of the toolbox,” he said. “We’ve already delayed for decades taking action on climate to avoid some of the negative impacts.”