ENS 48616
ENS Event | |
|---|---|
22:00 Dec 20, 2012 | |
| Title | Unanalyzed Condition Due to an Identified Degraded Fire Barrier |
| Event Description | During a walkdown on December 20, 2012 at 1600 CST, two degraded Appendix R fire barriers (walls) were identified. These barriers separate the Torus Room (Fire Area IV)/ 'A' RHR Room (Fire Area I) and the Torus Room (Fire Area IV)/ 'B' RHR Room (Fire Area II). The walls separate Appendix R fire safe shutdown divisional equipment.
A fire watch was established as a compensatory measure immediately following identification of the issue on December 20, 2012. The barrier affecting the 'B' RHR Room has been repaired on both sides. The barrier affecting the 'A' RHR Room has been repaired on the Torus Room side. The discovery of this non-compliance is being reported as an unanalyzed condition as defined by 10CFR50.72(b)(3)(ii)(B). The fire watch remains in place until verification of the completed repair is performed. The licensee notified the NRC Resident Inspector.
An eight hour report per 10 CFR 50.72(b)(3)(ii)(B) was conservatively reported on December 21, 2012 for degraded fire barriers between the Torus Room (Fire Area IV) and 'A' RHR Room (Fire Area I), and the Torus Room (Fire Area IV) and 'B' RHR Room (Fire Area II). Subsequent engineering analysis determined that the degraded fire barriers maintained the required degree of separation for redundant safe shutdown trains and plant safety was not significantly degraded. The 10 CFR 50.72(b)(3)(ii)(B) report is retracted. The licensee will notify the NRC Resident Inspector. Notified R3DO (Kunowski). |
| Where | |
|---|---|
Monticello  Minnesota (NRC Region 3) | |
| Reporting | |
| 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition | |
| Time - Person (Reporting Time:+2.1 h0.0875 days <br />0.0125 weeks <br />0.00288 months <br />) | |
| Opened: | Rick Davidson 00:06 Dec 21, 2012 |
| NRC Officer: | Vince Klco |
| Last Updated: | Feb 7, 2013 |
| 48616 - NRC Website
Loading map... {"minzoom":false,"maxzoom":false,"mappingservice":"leaflet","width":"350px","height":"250px","centre":false,"title":"","label":"","icon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"zoom":6,"defzoom":14,"layers":["OpenStreetMap"],"image layers":[],"overlays":[],"resizable":false,"fullscreen":false,"scrollwheelzoom":true,"cluster":false,"clustermaxzoom":20,"clusterzoomonclick":true,"clustermaxradius":80,"clusterspiderfy":true,"geojson":"","clicktarget":"","imageLayers":[],"locations":[{"text":"\u003Cb\u003E\u003Cdiv class=\"mw-parser-output\"\u003E\u003Cp\u003E\u003Ca class=\"mw-selflink selflink\"\u003EENS 48616\u003C/a\u003E - \u003Ca href=\"/Monticello\" title=\"Monticello\"\u003EMonticello\u003C/a\u003E\n\u003C/p\u003E\u003C/div\u003E\u003C/b\u003E\u003Cdiv class=\"mw-parser-output\"\u003E\u003Cp\u003EUnanalyzed Condition Due to an Identified Degraded Fire Barrier\n\u003C/p\u003E\u003C/div\u003E","title":"ENS 48616 - Monticello\n","link":"","lat":45.333647222222226,"lon":-93.8490361111111,"icon":"/w/images/6/6c/Xcel_Energy_icon.png"}],"imageoverlays":null} | |
Unit 1 | |
|---|---|
| Reactor critical | Critical |
| Scram | No |
| Before | Power Operation (100 %) |
| After | Power Operation (100 %) |