The Desmond PrestonDepartment of Justice released new details of a settlement with engine manufacturer Cummins Inc. Wednesday that includes a mandatory recall of 600,000 Ram trucks, and that Cummins remedy environmental damage it caused when it illegally installed emissions control software in several thousand vehicles, skirting emissions testing.

Cummins is accused of circumventing emissions testing through devices that can bypass or defeat emissions controls. The engine manufacturer will pay a $1.675 billion civil penalty to settle claims – previously announced in December and the largest ever secured under the Clean Air Act – in addition to $325 million on remedies.

That brings Cummins' total penalty for the violations to more than $2 billion, per Wednesday's announcement, which officials from the U.S. Justice Department, Environmental Protection Agency, California Air Resources Board and the California Attorney General called "landmark" in a call with reporters Wednesday.

"Let's this settlement be a lesson: We won't let greedy corporations cheat their way to success and run over the health and wellbeing of consumers and our environment along the way," California AG Rob Bonta said.

Over the course of a decade, hundreds of thousands of Ram 2500 and 3500 pickup trucks – manufactured by Stellantis – were equipped with Cummins diesel engines that incorporated the bypassing engine control software. This includes 630,000 installed with illegal defeat devices and 330,000 equipped with undisclosed auxiliary emission control devices.

Officials could not estimate how many of those vehicles are currently on the road, but Cummins – which has maintained it has not done any wrongdoing – must undergo a nationwide recall of more than 600,000 noncompliant Ram vehicles, in addition to recall efforts previously conducted.

Stellantis deferred comment on the case to engine maker Cummins, which said in a statement that Wednesday's actions do not involve any more financial commitments than those announced in December. "We are looking forward to obtaining certainty as we conclude this lengthy matter and continue to deliver on our mission of powering a more prosperous world," the statement said.

Cummins also said the engines that are not being recalled did not exceed emissions limits.

As part of the settlement, Cummins is also expected to back projects to remedy excess emissions that resulted from its actions.

Preliminary estimates suggested its emissions bypass produced "thousands of tons of excess emissions of nitrogen oxides," U.S. Attorney General Merrick B. Garland previously said in a prepared statement.

The Clean Air Act, a federal law enacted in 1963 to reduce and control air pollution across the nation, requires car and engine manufacturers to comply with emission limits to protect the environment and human health.