ALBUQUERQUE, N.M. — New Mexico regulators have received a formal proposal from the U.S. Department of Energy to close part of the nation's only underground nuclear waste repository due to safety and contamination concerns.
The repository has been shuttered since February 2014, when a chemical reaction inside an inappropriately packed drum of waste triggered a radiation release.
The closure halted the shipment of tons of Cold War-era waste from sites across the country, stalling a multibillion-dollar cleanup campaign by the Energy Department.
The incident also resulted in an overhaul of policies and procedures, costly work to mitigate the contamination, and a multimillion-dollar settlement with the state of New Mexico for numerous permit violations.
Under the proposal to close part of the underground area, federal officials want to install a series of steel barriers that would permanently seal off disposal rooms and other main corridors in the southern end, reducing the chance of waste disposal and mining activities stirring up dust and contamination.
The barriers would reduce the footprint of the contaminated areas by about 60 percent, officials said.
Maintenance and monitoring work underground have been limited due to the contamination and reduced ventilation, leaving workers to wear special protective gear and carry bulky monitoring equipment.
The closure plan was first announced in October and officials with the New Mexico Environment Department say they recently received hundreds of pages of documents that make up the federal government's formal request.
The documents cover changes to the state permit that governs the Waste Isolation Pilot Plant in southern New Mexico.
State Environment Secretary Butch Tongate said it will take some time for state regulators to review the proposal so it's unclear when a final decision will be made.
"We're going to get to it as soon as we can because I think if they do close it, it will enhance their ability to get restarted in an efficient way," he said.
The state is also awaiting a readiness report from the Energy Department and the contractor that manages the repository. Tongate said that will be reviewed to ensure everything required has been done to begin handling waste again.
State regulators also are preparing for their first inspection of the underground area since the radiation release occurred nearly three years ago.
"We'll be looking at safety aspects not only for their workforce but for the general public," Tongate said. "It all needs to be addressed to make sure everything they've done is aligned with that message of safety."
The federal Energy Department had hoped to resume some operations by the end of the year, but watchdogs are calling on Energy Secretary Ernest Moniz to follow federal environmental laws as his agency works to reopen the troubled repository.
The Natural Resources Defense Council and the Southwest Research and Information Center sent Moniz a letter this week, saying there hasn't been a public process under the National Environmental Policy Act with regards to resuming operations.
The groups are asking for a broad environmental review that would look at everything from corrective action plans to the potential effects of another catastrophic incident. They contend the department hasn't looked at alternatives as required by law.
Moniz has said repeatedly that reopening the waste plant is a top priority. His agency said Wednesday the letter was being reviewed but did not comment on the timing of reopening the facility.