A group of conservation organizations sued the Environmental Protection Agency on Monday, saying the agency unlawfully suspended Obama-era rules to cut methane pollution.
The lawsuit is another sign that environmentalists intend to use the courts to block President Donald Trump's effort to roll back energy regulations and climate change initiatives pushed by his predecessor.
Environmental groups have already sued the president over his approval of the Keystone XL pipeline and for seeking to overturn President Barack Obama's ban on offshore drilling in the Arctic. Some nonprofits, including the Natural Resources Defense Council, have also sued over Trump's executive order requiring federal agencies to repeal two regulations for every new one they propose.
Six conservation groups on Monday filed suit after the EPA last week suspended implementation of rules meant to prevent methane leaks from oil and gas operations. They said EPA Administrator Scott Pruitt issued a 90-day stay without giving the public advance notice or the opportunity to comment, as required by law.
"In its haste to do favors for its polluter cronies, the Trump EPA has broken the law," Meleah Geertsma, senior attorney at the Natural Resources Defense Council, said in a statement. "The Trump administration does not have unlimited power to put people's health in jeopardy with unchecked, unilateral executive action like this."
The groups are asking the District of Columbia Circuit Court of Appeals to review the EPA's action and either temporarily block it or throw it out altogether.
The EPA asserted in a press release last week that it has the authority to issue the stay under the Clean Air Act while it reviews the rule. Trump ordered the review as part of a wide-ranging executive order that targeted Obama-era climate policies.
An agency spokesperson told CNBC that the EPA does not comment on ongoing litigation.
This comes after Senate Republicans unsuccessfully attempted to overturn a similar Bureau of Land Management methane rule regulating drilling on federal and Native American land.
Both the EPA and BLM rule have been challenged in court by a number of oil-producing states with backing from the energy industry.
Industry groups such as the American Petroleum Institute say the methane rules are unnecessary, because many drillers are already tackling the problem themselves and the regulation does nothing to help those efforts.
Scientists recently concluded that the oil and gas industry produced far more methane emissions than previously thought, but leaks from the sector did not drive the increase in overall emissions since 2007. That is because the industry has indeed reduced leaks.
But the scientists also concluded that while the industry got better at preventing methane from escaping, increased production of oil and gas in the United States had offset the drop in leaks.
Methane accounts for a smaller share of greenhouse gas emissions from human activity than carbon dioxide and stays in the atmosphere for less time than CO2, but it is more efficient at trapping radiation, according to the EPA.
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