Marathon Oil agreed to spend $241.5 million to resolve federal allegations that it unlawfully emitted methane, a planet-warming greenhouse gas, and other pollutants from oil and gas facilities in North Dakota.
Under the proposed settlement announced on Thursday, the oil and gas producer, based in Houston, would pay a $64.5 million civil penalty. The federal government said it was the largest-ever fine for alleged violations of the Clean Air Act that took place at stationary infrastructure.
Marathon also agreed to spend $177 million to reduce future emissions in North Dakota, including on the Fort Berthold Indian Reservation, where the Environmental Protection Agency said the company had violated permitting requirements and other rules in recent years.
The settlement is part of a wider effort by the E.P.A. to rein in greenhouse gas emissions at oil and gas facilities.
Methane, the main ingredient in natural gas, can trap much more heat in the atmosphere over the short term than carbon dioxide can. As a result, regulators have made it a priority to reduce the release of methane, which can leak from pipes, gas terminals, cooking stoves and other equipment.
“E.P.A. is committed to doing everything possible to limit climate change and ensure a sustainable future,” David M. Uhlmann, an assistant administrator at the agency, said in a statement.
Marathon, which did not admit liability as part of the agreement, said it was pleased to resolve the matter without litigation. The company also produces oil and gas in Texas, New Mexico and Oklahoma.
The Justice Department, which brought a lawsuit against the company on behalf of the E.P.A., said Marathon failed to obtain the necessary permits or comply with emissions regulations at dozens of oil and gas production facilities in North Dakota.
Marathon has released an outsize share of the greenhouse emissions that are warming the planet, according to the Justice Department, which said the company ranked seventh in the industry for such emissions despite being the 22nd-largest oil producer as of 2022.
Marathon agreed to limit releases of volatile organic compounds, a class of pollutants that can harm humans and wildlife, and install equipment that would monitor flaring, the practice of burning natural gas that energy companies cannot easily dispose of or pipe to where it is needed. The company also said it would perform more frequent inspections and additional preventive maintenance. Marathon agreed to have an independent auditor review its permit applications.
“Findings from such inspection, monitoring and auditing activities may result in decisions to temporarily shut in or reduce production from certain wells and facilities,” Marathon said in a securities filing.
Taken together, Marathon’s new investments would, over five years, reduce emissions equivalent to taking 487,000 cars off the road, the E.P.A. said.
Marathon recently agreed to be acquired by its larger rival ConocoPhillips, part of a trend of consolidation in the U.S. oil industry.
The all-stock deal announced in May valued Marathon at around $17 billion, not including debt. The two companies said at the time that they expected to complete the transaction in the fourth quarter of this year.
The proposed settlement will be open for public comment for 30 days. Marathon said it did not expect the agreement to adversely affect its deal with ConocoPhillips.