New Mexico regulators on Saturday hit the U.S. government with more than $54 million in fines for violations at a nuclear waste facility where a fire broke out and radiation was released in two mishaps earlier this year.

The state blamed the energy agency for major procedural problems that led to an improperly maintained salt truck catching fire at the Waste Isolation Pilot Plant near Carlsbad on February 7 and an improperly packaged Los Alamos National Laboratory barrel of waste rupturing at the site a week later, the documents showed.

The leak exposed 22 workers to low levels of radiation that were not expected to threaten their health, according to Nuclear Waste Partnership, a contractor that operates the facility.

The New Mexico Environment Department also found that the response by the contractor and the federal energy agency were "less than adequate."

The Waste Isolation Pilot Plant, a salt mine where radioactive material is buried half a mile below ground, is not expected to be fully operational again for five years because of the incidents. The cost for initial recovery of the dump is estimated at $240 million, according to the U.S. Department of Energy.