The announcement came hours after a presidential commission urged federal officials to generate local support for alternative sites to the contentious Yucca Mountain repository in Nevada and suggested building regional storage sites to warehouse spent nuclear fuel in the meantime.
This year, a federal appeals court in Washington, D.C., threw out a lawsuit from Washington state and South Carolina, finding it was not an appropriate time to intervene because the NRC hadn't made a final decision on the status of Yucca Mountain.
The Obama administration canceled a plan to bury waste at the repository 100 miles from Las Vegas and sought to withdraw its license application before the agency. The NRC has yet to rule.
The latest lawsuit asks the court to determine that the NRC has unreasonably delayed consideration of the license application, to compel the agency to immediately resume consideration and provide a timeline for a decision.
Washington and South Carolina are home to millions of gallons of highly radioactive waste.