ENS 42072
ENS Event | |
|---|---|
13:00 Oct 21, 2005 | |
| Title | Unanalyzed Condition Due to Relocation of a Fire Door Boundary |
| Event Description | This event is being reported as 10CFR50.72(b)(3)(ii)(B), an unanalyzed condition that significantly degrades plant safety. A postulated fire water system line break did not take into consideration the movement of a fire door boundary. Consequently, the break may affect safe shutdown of the plant. The door boundary was moved in May 1999.
While assessing a calculation to update fire pump curves (CR 04-00422-04) it was found that the calculation does not appear to have been updated for the tornado depressurization event modifications (DCP 99-05014). Specifically, door DG-112 was moved to the control complex wall from the diesel generator wall. This door movement isolates the rattle space that was previously credited as a relief path for this internal flood. A full break is postulated for this line as the result of a safe shutdown earthquake. As the result of the postulated pipe break, both fire protection pumps are expected to auto start resulting in a break flow rate into the hallway of approximately 6,000 gpm. Standard Perry design practice is to assume a 30 minute duration for the pipe break flow isolation unless justified otherwise. The line in question was isolated at 2027 on 10/21/05. The valves are being maintained closed under administrative controls. The licensee notified the NRC Resident Inspector.
An 8-hour notification was made on October 24, 2005 under 10 CFR 50.72(b)(3)(ii)(B) for an unanalyzed condition that significantly degrades plant safety. The report was made due to a postulated break for a non-safety non-seismic fire water pipe that could possibly affect safe shutdown of the plant. An evaluation was completed on October 28, 2005. This evaluation confirmed that the current plant configuration is consistent with the design basis. The evaluation used for the original event notification assumed a full break of the involved piping. Perry design basis for this moderate energy system is a leakage crack. The postulated leakage from the crack in the piping remains within design basis and does not significantly degrade plant safety. Since Perry remains in compliance with design basis and there is no unanalyzed condition that significantly degrades plant safety, there is no reportable condition. Therefore, ENF 42072 is retracted. The licensee notified the NRC Resident Inspector. Notified R3DO (Lipa). |
| Where | |
|---|---|
| Perry Ohio (NRC Region 3) | |
| Reporting | |
| 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition | |
| Time - Person (Reporting Time:+71.68 h2.987 days <br />0.427 weeks <br />0.0982 months <br />) | |
| Opened: | Robert Kidder 12:41 Oct 24, 2005 |
| NRC Officer: | Arlon Costa |
| Last Updated: | Oct 28, 2005 |
| 42072 - 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 42072\u003C/a\u003E - \u003Ca href=\"/Perry\" title=\"Perry\"\u003EPerry\u003C/a\u003E\n\u003C/p\u003E\u003C/div\u003E\u003C/b\u003E\u003Cdiv class=\"mw-parser-output\"\u003E\u003Cp\u003EUnanalyzed Condition Due to Relocation of a Fire Door Boundary\n\u003C/p\u003E\u003C/div\u003E","title":"ENS 42072 - Perry\n","link":"","lat":41.79572777777778,"lon":-81.145375,"icon":"/w/images/a/ad/FirstEnergy_icon.png"}],"imageoverlays":null} | |
Unit 1 | |
|---|---|
| Reactor critical | Critical |
| Scram | No |
| Before | Power Operation (100 %) |
| After | Power Operation (100 %) |
WEEKMONTHYEARENS 570922024-04-25T21:55:00025 April 2024 21:55:00
[Table view]10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Configuration of B and C Residual Heat Removal Loops in an Unanalyzed Condition ENS 564552023-04-06T20:46:0006 April 2023 20:46:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Main Steam Line 'B' Leakage in Excess of Tech Spec Limits ENS 536752018-10-19T04:00:00019 October 2018 04:00:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Postulated Hot-Short Fire Event That Could Adversely Impact Safe Shutdown Equipment ENS 536442018-10-04T04:00:0004 October 2018 04:00:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Postulated Hot Short Fire Event That Could Adversely Impact Safe Shutdown Equipment ENS 502132014-06-19T20:28:00019 June 2014 20:28:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Unanalyzed Condition Due to a Postulated Hot Short That Could Affect Safe Shutdown Equipment ENS 494462013-10-17T17:00:00017 October 2013 17:00:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Postulated Hot Short Fire Event That Could Adversely Impact Safe Shutdown Equipment ENS 475452011-12-21T18:59:00021 December 2011 18:59:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Groundwater Level May Exceed Design Assumptions ENS 475082011-11-17T01:00:00017 November 2011 01:00:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Postulated Flooding Scenario Results in Unanalyzed Condition ENS 470242011-07-05T22:15:0005 July 2011 22:15:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Two Appendix R Wiring Issues That Could Potentially Affect the Ability to Shutdown ENS 436032007-08-27T20:45:00027 August 2007 20:45:00 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 Grating Inside Containment Found Unsecured ENS 420722005-10-21T13:00:00021 October 2005 13:00:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Unanalyzed Condition Due to Relocation of a Fire Door Boundary ENS 414172005-02-17T22:30:00017 February 2005 22:30:00 10 CFR 50.72(b)(3)(v)(A), Loss of Safety Function - Shutdown the Reactor, 10 CFR 50.72(b)(3)(v)(B), Loss of Safety Function - Remove Residual Heat, 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 Emergency Diesel Generators Declared Inoperable Due to Unanalyzed Condition ENS 413442005-01-19T07:37:00019 January 2005 07:37:00 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 Emergency Diesel Generators Declared Inoperable Due to an Unanalyzed Condition ENS 404042003-12-22T01:21:00022 December 2003 01:21:00 10 CFR 50.72(b)(3)(v)(A), Loss of Safety Function - Shutdown the Reactor, 10 CFR 50.72(b)(3)(v)(B), Loss of Safety Function - Remove Residual Heat, 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 Potential Impact to Safe Shutdown Due to Control Complex Ventilation Inoperability 2024-04-25T21:55:00 | |