The U.S. Nuclear Regulatory Commission (NRC) has completed follow-up onsite reviews of selected nuclear power plants undergoing decommissioning and found no problems with their Y2K program activities.
The primary Year 2000 (Y2K)-related health and safety concern at plants that no longer generate power and are being decommissioned is to assure sufficient cooling and shielding of the spent fuel in water-filled spent fuel pools.
Currently, there are 19 permanently shut down nuclear power plants, 14 of which have spent fuel remaining on site.
Starting in early December, NRC reviewed the six facilities that have been shut down in the last four years and thus have the highest level of heat generated from the natural decay of spent fuel.
Reviews covered management controls, staffing, system and component repairs or replacements and plans for responding to any unexpected event.
The remaining eight plants (shut down for more than four years) have spent fuel that generates relatively low levels of heat and can remain in a safe state for three to four weeks, if there is an interruption in the cooling system.
Early this year, the NRC staff contacted all decommissioning reactor licensees and determined that they were addressing Y2K readiness, but no onsite reviews of Y2K activities were conducted.
The likelihood of Y2K-related problems causing hazardous conditions at a nuclear power plant undergoing decommissioning is relatively low because heat loads are low, procedures are in place to respond to off-normal situations, and systems in the plant are mostly analog and unaffected by Y2K computer issues.