The Environmental Protection Agency and Department of Justice said the settlement requires Marathon to reduce climate- and health-harming emissions from those facilities and will result in over 2.3 millions tons worth of pollution reduction.

“This historic settlement — the largest ever civil penalty for violations of the Clean Air Act at stationary sources — will ensure cleaner air for the Fort Berthold Indian Reservation and other communities in North Dakota, while holding Marathon accountable for its illegal pollution,” said Attorney General Merrick B. Garland.

Marathon officials did not immediately respond to a request for comment.

While Marathon is the country’s 22nd-largest oil producer based on 2022 data, the federal agencies said, it’s also the seventh-largest emitter of greenhouse gas emissions in the oil and gas industry. Much of its emissions come from flaring, the industry practice of burning off waste gases, which also releases methane, a particularly potent contributor to climate change.

The settlement calls for Marathon to eliminate the equivalent of over 2.25 million tons of carbon-dioxide emissions over the next five years, which the agencies said was tantamount to taking 487,000 cars off the road for one year, and will also eliminate nearly 110,000 tons of volatile organic compound missions.