【Technical Overview】
The SPF integrity evaluation framework is based on the seismic hazard data generated through the procedures set by Taiwan Power Company (TPC) using Senior Seismic Hazard Analysis Committee Level 3 (SSHAC Level 3) procedures. The study includes both structural and non- structural analysis. The structural analysis criteria are provided for evaluating potential failure of SFP walls and floors. For non-structural aspects the following items are considered, such as piping connections, fuel gates, and anti-siphoning devices, as well as an evaluation of SFP sloshing and an approach for assessing the heat up and boil-off of SFP water inventory.
 
Based on the requirements of Near-Term Task Force Recommendations 2.1 (NTTF 2.1), this research is to develop a methodology applicable to provide guidelines for use in Taiwan. It investigates evaluation process and acceptance criteria for extreme events such as seismic. Criteria are also provided for SFP seismic-induced sloshing losses and boil-off losses using site-specific parameters to evaluate the ability of SFPs to retain adequate water inventory for 72 hours.


Figure 1.Framework for the integrity assessment of SFPs


Figure 2.SFP Evaluation Results

【Project Planning/Technological Application】
Overall, the study ensures the safety of SFP integrity in Taiwan. Developing a methodology that aligns with the requirements of Nuclear Safety Commission (NSC), NARI systematically considers all seismically induced failures that could result in rapid draining and guarantee the capability of SFPs to deal with extreme events. It would mitigate the public concerns about the nuclear safety. The approach also provides criteria for evaluating both the structural and non-structural aspects of the SFP integrity. It can be applied to the SFPs of any nuclear power plants, regardless of whether they are in operation or undergoing decommissioning. Currently, the results are also being applied to other technical services cases.
 
【Future Planning】
Currently, SFPs remain at the critical first-line of spent fuels storage and management in the future. Therefore, the technology developed in this study can continue to provide crucial expertise for SFPs safety assessment. It can be applied to NPPs that are in operation or decommissioning status and also aids regulatory authorities and owners in clarifying SFPs safety. This ensures that the integrity of SFPs continue to comply with relevant regulatory requirements, thereby enhancing public confidence to the safety of nuclear power plants.

【Contact Information】
Name: Hsu, Hao-Ti
Phone: 03-4711400 Ext. 6126
E-mail：hthsu@nari.org.tw