The Environmental Protection Agency (EPA) announced that General Motors (GM) must pay $146 million in fines due to the results of an investigation revealing that 5.9 million vehicles made by the company emitted excess greenhouse gas emissions.

"This agreement is the result of an EPA investigation that identified excess CO2 emissions from approximately 5.9 million 2012-2018 model year (MY) GM vehicles currently in use."

The manufacturer must also remove 50 million metric tons of greenhouse gas credits. According to the EPA:

"The U.S. Environmental Protection Agency (EPA) announced that General Motors (GM) has agreed to retire approximately 50 million metric tons (megagrams) of greenhouse gas credits to resolve excess CO2 emissions identified through EPA’s light-duty vehicle in-use testing program."

Vehicles emit 10% more CO2

The result of the investigation is that some GM vehicles manufactured between 2012 and 2018 emitted about 10% more greenhouse gas emissions than their compliance tests had said they did. EPA Administrator Michael Regansaid said in a statement:

"EPA’s vehicle standards depend on strong oversight in order to deliver public health benefits in the real world. ... Our investigation has achieved accountability and upholds an important program that’s reducing air pollution and protecting communities across the country."

The affected vehicles include Chevrolet, GMC and Cadillac models. The EPA stated that the violations were unintentional and that the vehicles will remain on the road and cannot be repaired.