As we previously reported, the Nuclear Regulatory Commission (NRC) established a Working Group to provide risk-informed enhancements to the Independent Spent Fuel Storage Installation (ISFSI) inspection program. NRC released its recommendations to the NRC’s Office of Nuclear Material Safety and Safeguards earlier this month. If adopted, the recommendations would, among other things, reduce the frequency and time spent conducting recurring, routine ISFSI inspections while increasing inspections during initial and extended loading campaigns and maintaining existing oversight of new construction activities.
During 2018, the NRC received public comments about the need to improve ISFSI inspections, including a recommendation from the Nuclear Energy Institute to forego routine recurring inspections of ISFSIs due to the inherently passive nature of spent fuel storage. In June 2019, the NRC established a working group to evaluate the current ISFSI inspection program. The working group was tasked with developing a clearer, risk-informed, comprehensive, and consistent approach to ISFSI inspections across the NRC’s four regions. It consisted of a representative from each of the regions, the Office of Nuclear Material Safety and Safeguards, and the Office of Nuclear Reactor Regulation, and its scope included onsite ISFSI construction, loading operations and dry-runs of loading, and ISFSI monitoring. Topics such as spent fuel transportation, vendor inspections, aging management, and ISFSI security were outside of the working group’s purview. In March 2020 and after several public meetings, the working group released its final recommendations.
Proposed changes to the inspection program include the following:
- Routine recurring inspections would change from 132 hours every two years to 96 hours (plus 10 in-office hours) every three years.
- Routine monitoring inspections would change from 24 hours every two years to 24 hours every three years.
- Quarterly inspections of extended loading campaigns would change from as-needed to 96 hours every quarter.
- Oversight inspections of new construction activities would change from 420 hours to 480 hours. New construction activities include design reviews, preoperational testing, initial loading oversight, changes to dry cask storage systems, and ISFSI construction or expansion. The change in the level of effort, however, does not impose new requirements.
- All other inspections will continue to occur on an as-needed basis.
The working group also proposed changes to ISFSI inspector training and qualifications. One proposal is to develop a cross-qualification program for reactor inspectors already qualified as a resident or regional engineering inspector. The recommendations would allow for greater flexibility for regions to decide who conducts the inspections by allowing a streamlined qualification process for NRC inspectors qualified to perform other inspections.
While some members of the public have criticized NRC’s proposals as a purported reduction in safety, the working group’s efforts recognize the inherently passive and safe nature of spent fuel storage at an ISFSI. The working group informed its recommendations using probabilistic risk analyses, byproduct material radiation exposure studies relating to irradiators and fixed radiographic installations, subject matter expertise, operating experience, and lessons learned from 30 years of ISFSI inspection history.
The final decision will be made by the director of the NRC’s Division of Fuel Management. The working group’s implementation goal is fiscal year 2021.