ENS 55231
ENS Event | |
---|---|
13:30 May 3, 2021 | |
Title | |
Event Description | At 0930 EDT on 5/3/2021, it was determined that during entries into the Fermi 2 Reactor Building Steam Tunnel (RBST) on 4/17/2021, 4/18/2021, and 4/21/2021 that the door was not controlled according to site procedures. The RBST door is credited as a hazard barrier for various high-energy line break (HELB) scenarios. On the identified dates, the RBST door was left open for brief periods during maintenance related activities in the RBST. This condition is not bounded by existing analyses as the door is assumed to be closed throughout a HELB event. The time period that the door was open was less than one hour in each case, as stay times in the room are inherently limited by industrial and radiological conditions. Individuals remained in the area to close the door if needed, but existing analyses do not address the ability to perform those actions under all HELB scenarios.
There is no impact to the health and safety of the public or plant personnel as the door is currently closed and latched and access into the area has been restricted to normal ingress and egress per site procedures, which ensures consistency with existing analyses. Therefore, this event is being reported as an eight-hour, non-emergency notification per 10 CFR 50.72(b)(3)(ii)(B). Investigation into the cause is ongoing. Preliminary review of the extent of this condition identified entries into the RBST on other occasions during the past three years where the conditions may also have not been bounded by existing analyses. The additional occasions where the door may have been held open were on 9/22/2018 (MODE 3), 10/26/2018 (MODE 1 ), 11/2/2018 (MODE 1), and 3/21/2020 (MODE 3). Each of these instances was also less than one hour with the exception of the occurrence beginning on 10/26/2018 which lasted approximately 10 hours1.157407e-4 days <br />0.00278 hours <br />1.653439e-5 weeks <br />3.805e-6 months <br /> to support packing leak repairs on a HPCI [High Pressure Coolant Injection] Outboard Isolation Valve. The licensee notified the NRC Resident Inspector. |
Where | |
---|---|
Fermi ![]() Michigan (NRC Region 3) | |
Reporting | |
10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition | |
Time - Person (Reporting Time:+2.15 h0.0896 days <br />0.0128 weeks <br />0.00295 months <br />) | |
Opened: | Jeff Myers 15:39 May 3, 2021 |
NRC Officer: | Brian Lin |
Last Updated: | May 3, 2021 |
55231 - 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 55231\u003C/a\u003E - \u003Ca href=\"/Fermi\" title=\"Fermi\"\u003EFermi\u003C/a\u003E\n\u003C/p\u003E\u003C/div\u003E\u003C/b\u003E\u003Cdiv class=\"mw-parser-output\"\u003E\u003Cp\u003E\u003Ca href=\"/Unanalyzed_Condition\" title=\"Unanalyzed Condition\"\u003EUnanalyzed Condition\u003C/a\u003E\n\u003C/p\u003E\u003C/div\u003E","title":"ENS 55231 - Fermi\n","link":"","lat":41.96295277777778,"lon":-83.25779444444444,"icon":"/w/images/5/5b/DTE_Energy_icon.png"}],"imageoverlays":null} | |
Unit 2 | |
---|---|
Reactor critical | Critical |
Scram | No |
Before | Power Operation (100 %) |
After | Power Operation (100 %) |
WEEKMONTHYEARENS 552312021-05-03T13:30:0003 May 2021 13:30:00
[Table view]10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Unanalyzed Condition ENS 537122018-11-01T04:00:0001 November 2018 04:00:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition En Revision Imported Date 12/31/2018 ENS 536742018-10-19T04:00:00019 October 2018 04:00:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Low Pressure Core Injection Pumps Incapable of Automatic Startup ENS 527242017-05-02T21:00:0002 May 2017 21:00:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Unanalyzed Condition for Combustion Turbine Generator Configuration ENS 523422016-11-02T14:34:0002 November 2016 14:34:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Unanalyzed Condition for Control Rod Drop Accident at Low Power ENS 522142016-08-31T23:50:00031 August 2016 23:50:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Unanalyzed Condition with a Potential Tornado ENS 522022016-08-25T20:29:00025 August 2016 20:29:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Mechanical Draft Cooling Tower Declared Inoperable ENS 514402015-10-02T12:25:0002 October 2015 12:25:00 10 CFR 50.72(b)(3)(v)(A), Loss of Safety Function - Shutdown the Reactor, 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Loose Safety Relief Valve Discharge Flange Bolts ENS 422242005-12-23T03:25:00023 December 2005 03:25:00 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident, 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Eecw Temperature Control Valve Not Fully Open ENS 418472005-07-18T02:31:00018 July 2005 02:31:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Unanalyzed Condition of Maintenance Bus Tie Breakers ENS 418162005-06-30T23:31:00030 June 2005 23:31:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Unanalyzed Condition Related to the Standby Feedwater Pumps and Control Circuits ENS 417142005-05-18T22:50:00018 May 2005 22:50:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Identification of Design and Operating Procedure Deficiencies Related to Appendix R Events ENS 415512005-03-30T21:00:00030 March 2005 21:00:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Identification of Design and Operating Procedure Deficiencies 2021-05-03T13:30:00 | |