The complaint was filed on behalf of the Environmental Protection Agency and the U.S. Interior Department's Bureau of Safety and Environmental Enforcement against ATP Oil and Gas Corp. and ATP Infrastructure, LP.
Both entities are accused of failing to operate the wastewater treatment facility on its floating oil and gas production platform on the U.S. continental shelf. An undetermined amount of oil was released in May and the company is accused of releasing chemical dispersant to cover the incident.
The Justice Department said chemical dispersants were added in a way that made it undetectable in samples meant to confirm ATP was in compliance with the Clean Water Act.
"According to the complaint, the dispersant had been used from at least October 2010 to March 2012," the department stated.
ATP's offshore facility is in the Mississippi Canyon area in the Gulf of Mexico, about 45 miles off the coast of Louisiana.
Neither of the parties involved issued a statement related to the charges, filed in the District Court for the Eastern District of Louisiana. ATP filed for bankruptcy in August.