Holtec Palisades, the nuclear power plant that is scheduled to make history by restarting operations after being shut down forever, will also go down in history for another reason. The U.S. Nuclear Regulatory Commission has granted it a one-time license amendment to handle the fuel assembly with special equipment after a mishap on August 30 left the assembly tilted at a 30-degree angle. Located on a 432-acre site, five miles away from South Haven, Michigan, the Palisades nuclear power plant is home to a single pressurized water reactor. It can produce upto 725 megawatts of electricity. Entergy operated the plant, shut it down in 2022, and sold it to Holtec for dismantle and remove radioactive waste. Soon after the acquisition, though, Holtec received financial backing to restart operations and even secured a power-purchase agreement to facilitate the restart. In early August, fuel loading began at the reactor site, marking a major milestone toward the restart. However, for several weeks, the company did not disclose anything about a mishap that prevented it from completing the work. Why does Palisades need an exemption? During a regular refueling operation, a machine moves the fuel assembly through an underwater transfer tube connecting the reactor cavity to the spent fuel pool. However, during its refueling operation at Palisades, one nuclear fuel assembly tilted from its upright position inside the reactor vessel. It remained lodged at a 30-degree angle, with its lower end resting on the reactor core and its upper end against the core shroud. Even though the fuel rods and cladding of the reactor vessel remain intact, the assembly frame has been affected by screws in the facing damage that hamper the team’s ability to lift it with normal equipment. Holtec wants to move the fuel assembly with a specially designed movement device and use the facility’s polar crane to lift the assembly from its tilted position and then move it onto a custom fuel transfer canister positioned in the reactor’s cavity. To do this, Palisades sought a one-time exemption from the U.S. NRC for its license, which the NRC has now granted, and Holtec has 10 days to complete the job. Mitigating risks of the procedureThe U.S. NRC has called this a ‘first-of-its-kind fuel movement process, where workers plan to lift a 49,000-pound loaded canister from the water that provides radiation shielding. Once drained, workers will move the canister through the containment building’s open equipment hatch and into an auxiliary building on an existing rail system. Here, another crane will rotate it vertically and lower it into the spent fuel pool. The operation is unusual because the fuel assembly will spend some time outside the water, where it is shielded but not sealed and risks contamination exposure if a fuel rod ruptures. After reviewing Holtec’s calculations of potential worker risk in such an event, the NRC is convinced exposure remains within federal limits and is therefore allowing the request under exigent circumstances, since fuel loading has stalled. A former engineer at Palisades has questioned whether the NRC must make such exemptions to favor a faster facility restart. Holtec, on its part, has said that the entire operation will be carried out under cameras, and workers will stop and evaluate their steps if the cameras show a gap of more than two inches between the assembly and canister support pedestals.