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| Start date | Reporting criterion | Title | Event description | System | LER | |
|---|---|---|---|---|---|---|
| ENS 50454 | 12 September 2014 20:47:00 | Other Unspec Reqmnt | Stored Fuel May Not Meet Fuel Specifications or Loading Conditions for Hi-Storm 100 Cask System | Arkansas Nuclear One (ANO) identified the potential for stored fuel that does not meet the fuel specifications or loading conditions of the Certificate of Compliance (CoC) for the HI-STORM 100 Cask System. Investigation into the cause of a Control Room Emergency Ventilation System (CREVS) actuation on the morning of 9/12/2014 led to sampling of helium circulating through the Multi-Purpose Canister (MPC-24-060) as part of the Forced Helium Dehydration process in the final stages of cask loading. Sample results indicated the presence of Kr-85. Kr-85 is a fission product that indicates the potential for the fuel that does meet the selection criteria for the HI-STORM 100 Cask System. All fuel assemblies loaded into MPC-24-060 were checked to confirm their intact status (a cask Certificate of Conformance requirement) as part of the selection process. Each assembly's status as intact is based on in-mast sipping and/or ultrasonic testing performed subsequent to their final operating cycle. Results of these sipping and ultrasonic test campaigns are maintained in a comprehensive engineering report used to verify assembly status during cask fuel selection. Per the CoC for the Hi-STORM 100 Cask System, Appendix B, Section 1.0, the definition of 'INTACT FUEL ASSEMBLY' is a fuel assembly without known or suspected cladding defects greater than pinhole leaks or hairline cracks, and which can be handled by normal means. Given the presence of Kr-85 along with the fuels history, it cannot be confirmed that all fuel assemblies meet the definition of 'Intact' and would not meet the CoC Requirements for Fuel to be stored in the HI-STORM 100 SFSC System (Section 2.1.1). The NRC Resident Inspector has been notified. | Control Room Emergency Ventilation | |
| ENS 41276 | 20 December 2004 21:30:00 | Other Unspec Reqmnt | Suspected Failed Fuel Assemblies | Arkansas Nuclear One (ANO) was verbally notified at 1530 CST on 12/20/04 by Framatone ANP, Inc. that a secondary review of preliminary results of fuel UT data evaluations resulted in conservative reclassifications of assemblies as now being suspect of containing a failed pin. This verbal notification was documented in subsequent correspondence received from Framatone on 12/21/04. Specifically, rods are now suspected of being failed in ANO Unit 2 fuel assemblies AKC401, AKC504, AKD001, AKF103, and AKF110, which were previously identified as clear of fuel failures based on re-scan data as determined in the preliminary report. The identified assemblies were loaded in Holtec Cask Numbers 10, 11, 12, and 13, during the November and December, 2004 cask loading campaign. Appendix B, Section 2.1.1, of the Certificate of Compliance (CoC) Number 1014 for the Holtec HI-STORM 100 allows for the loading of "intact" fuel assemblies. Based on the new information from Framatone, the suspect fuel assemblies do not meet the requirements of "intact". Section 2.2 of the Holtec CoC requires a 24-hour Notification for the failure to meet fuel specifications or loading conditions. The licensee notified the NRC Resident Inspector. |