INDIANAPOLIS (WISH) — Columbus, Indiana-based Cummins Inc. has agreed in principle to pay nearly $1.7 billion to settle claims it violated the Clean Air Act, the U.S. Department of Justice said Friday.

Under the agreement, Cummins will pay a penalty of $1.675 billion for installing emissions defeat devices on hundreds of thousands of engines.

The Clean Air Act requires automakers and engine manufacturers to ensure their products meet U.S. emissions standards.

Defeat devices are parts or software that bypass, defeat, or render inoperative emissions controls such as emission sensors and onboard computers.

“The types of devices we allege that Cummins installed in its engines to cheat federal environmental laws have a significant and harmful impact on people’s health and safety,” U.S. Attorney General Merrick Garland said in a release.

The Justice Department accused Cummins of installing defeat devices on 630,000 model year 2013 to 2019 RAM 2500 and 3500 pickup truck engines and of adding auxiliary emission control devices to 330,000 model year 2019-2023 RAM 2500 and 3500 pickup truck engines.

“In this case, our preliminary estimates suggest that defeat devices on some Cummins engines have caused them to produce thousands of tons of excess emissions of nitrogen oxides. The cascading effect of those pollutants can, over long-term exposure, lead to breathing issues like asthma and respiratory infections,” Garland said.

The $1.675 billion penalty would be the largest ever for a Clean Air Act violation and the second-largest environmental penalty ever secured by the DOJ.

Cummins designs, manufactures, sells, and services diesel and alternative fuel engines, generators, and related equipment. The company has several thousand workers at its facilities in Indiana and more than 60,000 employees worldwide.