ENS 53858
ENS Event | |
|---|---|
22:05 Feb 1, 2019 | |
| Title | En Revision Imported Date 4/3/2019 |
| Event Description | EN Revision Text: NO SEISMIC ANALYSIS FOR CANISTER TRANSPORT PROCESS
During follow-up reviews resulting from the Aug. 3, 2018 canister downloading event (EN#53605), Southern California Edison [SCE] became aware of a condition where, during short periods of the canister transport process, the Vertical Cask Transporter (VCT) could have been operated without a supporting seismic analysis while transporting loaded canisters for storage. SCE has decided to conservatively report this issue. The VCT is a mobile gantry crane that is used to transport and download fuel canisters into an Independent Spent Fuel Storage Installation (ISFSI) enclosure. Twenty-nine canisters have been downloaded into the San Onofre nuclear plant ISFSI in this manner since January, 2018. The Holtec UMAX Certificate of Compliance requires that lifting of a loaded spent fuel canister must be performed with redundant (i.e., single-failure-proof) load drop protection features. Inherent in the definition is the ability to withstand seismic loading. SCE identified that although applicable rigging and downloading procedures were followed, a supporting seismic analysis should be developed for the short duration periods in the process where the canisters are transitioned to rigging. Southern California Edison has directed its vendor, Holtec, to perform this further seismic analysis. While the additional analysis may conclude that the VCT is stable and functional during these transitioning periods, SCE will work with the vendor should modifications to the canister transport process become necessary. SCE is making this notification in accordance with the requirements of 10 CFR 72.75(d)(1). There was no seismic event that resulted in damage to the VCT or a spent fuel canister during the fuel transfer campaign. All 29 spent fuel canisters are currently in safe storage within the ISFSI.
On 4/2/19, Southern California Edison (SCE) is retracting San Onofre Nuclear Generating Station (SONGS) Event Report 53858 dated February 2, 2019 for the Independent Spent Fuel Storage Installation (ISFSI). SCE conservatively submitted the event report under 72.75(d)(1) after it was initially determined the Vertical Cask Transporter (VCT) may have been operated for short periods of time during the canister transport process without a supporting seismic evaluation, contrary to the requirements of the Certification of Compliance (COC). A revision to the calculation by the vendor has subsequently confirmed the transport process and VCT operation met the seismic requirements of the Holtec COC. Therefore, Event Report No. 53858 is retracted. Notified R4DO (Gaddy) and via E-mail IRD MOC (Kennedy) and NMSS Events Notification E-mail group. |
| Where | |
|---|---|
| Southern California Edison Company San Clemente, California (NRC Region 4) | |
| License number: | GL |
| Organization: | San Onofre |
| Reporting | |
| 10 CFR 72.75(d)(1), ISFSI Safety System Functional Failure | |
| Time - Person (Reporting Time:+15.65 h0.652 days <br />0.0932 weeks <br />0.0214 months <br />) | |
| Opened: | Michael Johnson 13:44 Feb 2, 2019 |
| NRC Officer: | Ossy Font |
| Last Updated: | Apr 2, 2019 |
| 53858 - NRC Website | |
Southern California Edison Company with 10 CFR 72.75(d)(1), ISFSI Safety System Functional Failure | |
WEEKMONTHYEARENS 538582019-02-01T22:05:0001 February 2019 22:05:00
[Table view]10 CFR 72.75(d)(1), ISFSI Safety System Functional Failure En Revision Imported Date 4/3/2019 ENS 537982018-12-19T08:00:00019 December 2018 08:00:00 10 CFR 72.75(d)(1), ISFSI Safety System Functional Failure Spent Fuel Transfer Vehicle Outside Seismic Analysis Limits ENS 536052018-08-03T08:00:0003 August 2018 08:00:00 10 CFR 72.75(d)(1), ISFSI Safety System Functional Failure Spent Fuel Canister Became Bound During Download Into Dry Storage 2019-02-01T22:05:00 | |