Transocean Deepwater Inc., an oil drilling company, formally pleaded guilty on Thursday to a misdemeanor charge and will pay $400 million in criminal penalties, the latest action in the 2010 Gulf of Mexico oil spill.

U.S. District Judge Jane Triche Milazzo in New Orleans accepted the guilty plea to violating the Clean Water Act plea and imposed sentence, the Justice Department announced Thursday. Transocean agreed last month to plead guilty to the misdemeanor charge and to pay $1 billion in civil penalties along with the criminal penalty. Another judge will decide whether to accept the civil penalty portion.

The penalties totaling $1.4 billion represent the second-largest recovery in an environmental case, following the $4 billion criminal sentence imposed on BP Exploration and Production Inc. in connection with the same oil spill, the Justice Department said. Most of the $1.4 billion will fund environmental-restoration projects and spill-prevention research and training.