ENS 50994
From kanterella
Jump to navigation
Jump to search
ENS Event | |
|---|---|
22:45 Apr 19, 2015 | |
| Title | Unanalyzed Condition Due to Non Compliance with 10 Cfr 50 App R |
| Event Description | On April 19, 2015, it was determined that in the event of an Appendix-R fire in the Control Room/Relay Room, fire induced circuit damage can potentially result in Reactor Coolant Pump's (RCP) restarting. Procedure F5 APP B does not take actions to open RCP DC knife switches as required per Appendix R calculation GEN-PI-026, GEN-PI-054, and GEN-PI-055. Neither unit is currently susceptible to this condition due to the installation of improved RCP seals which allow adequate time to restore seal cooling prior to seal failure. However, the condition has occurred within three years of the time of discovery and is reportable under 10 CFR 50.72(b)(3)(ii)(B).
The Appendix R analysis requires that manual actions are taken to ensure that the RCPs are tripped and actions are taken to prevent restarting of the RCPs. The RCPs breaker must be verified open at the associated bus and DC knife switches located in the breaker cubicles are to be opened. These actions are required due to fire induced, loss of remote trip (spurious breaker closure) and loss of RCP seal cooling water and loss of Component Cooling (CC) water to the thermal barrier heat exchanger. These actions are required to achieve and maintain Mode 3, Hot Standby in the event of a catastrophic fire that results in the functional loss and/or evacuation of the Control Room/Relay Room. Current procedures verify the RCP breakers are open; however, they do not open the DC knife switch and therefore a hot short could result in a RCP restarting. This procedure omission meets the reporting criteria for 10 CFR 50.72(b)(3)(ii)(B) as an unanalyzed condition that significantly degrades plant safety. The protection of the health and safety of the public was not affected by this issue. The licensee has notified the NRC Senior Resident Inspector. |
| Where | |
|---|---|
Prairie Island  Minnesota (NRC Region 3) | |
| Reporting | |
| 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition | |
| Time - Person (Reporting Time:+0.32 h0.0133 days <br />0.0019 weeks <br />4.38336e-4 months <br />) | |
| Opened: | Tom Hold 23:04 Apr 19, 2015 |
| NRC Officer: | Mark Abramovitz |
| Last Updated: | Apr 19, 2015 |
| 50994 - NRC Website | |
Unit 1 | |
|---|---|
| Reactor critical | Not Critical |
| Scram | No |
| Before | Cold Shutdown (0 %) |
| After | Cold Shutdown (0 %) |
Unit 2 | |
|---|---|
| Reactor critical | Critical |
| Scram | No |
| Before | Power Operation (100 %) |
| After | Power Operation (100 %) |
WEEKMONTHYEARENS 526382017-03-20T21:39:00020 March 2017 21:39:00
[Table view]10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Historical Event Related to Past Operability ENS 518772016-04-21T20:50:00021 April 2016 20:50:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Missing Fire Barriers ENS 516422016-01-08T01:00:0008 January 2016 01:00:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Unanalyzed Condition - Appendix R Credited Procedures Not in Place ENS 516162015-12-21T22:25:00021 December 2015 22:25:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Unanalyzed Condition Due to Non-Compliant Fire Protection Manual Operator Actions ENS 514982015-10-26T12:03:00026 October 2015 12:03:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Unanalyzed Condition Associated with a High Energy Line Break ENS 509942015-04-19T22:45:00019 April 2015 22:45:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Unanalyzed Condition Due to Non Compliance with 10 Cfr 50 App R ENS 508012015-02-10T08:50:00010 February 2015 08:50:00 10 CFR 50.72(b)(3)(v)(B), Loss of Safety Function - Remove Residual Heat, 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Voids Identified That Result in an Unanalyzed Condition ENS 505312014-10-13T19:25:00013 October 2014 19:25:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Unanalyzed Condition Due to a Missing Fire Barrier ENS 505232014-10-10T22:17:00010 October 2014 22:17:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Missing Fire Barrier ENS 504752014-09-19T18:53:00019 September 2014 18:53:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Unanalyzed Condition Due to Missing Fire Barriers ENS 503622014-08-08T15:26:0008 August 2014 15:26:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Unanalyzed Condition Due to Lack of Appropriate Fuse Protection ENS 496852013-12-31T15:33:00031 December 2013 15:33:00 10 CFR 50.72(b)(3)(v)(B), Loss of Safety Function - Remove Residual Heat, 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Unanalyzed Condition Due to Removal of Multiple Steam Generator Lateral Support Shims and Bumpers ENS 493612013-09-19T17:20:00019 September 2013 17:20:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition No Documented Plan in Place to Receive Additional Fuel Oil During Maximum Probable Flood Condition ENS 491282013-06-17T21:15:00017 June 2013 21:15:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Potential Unanalyzed Condition - Carbon Dioxide Fire Suppression System Does Not Meet Design Requirements ENS 479492012-05-22T21:30:00022 May 2012 21:30:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Unanalyzed Condition Identified During a Fire Protection Review ENS 475222011-12-09T17:59:0009 December 2011 17:59:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Unanalyzed Condition- Degraded Fire Barrier Between Fire Areas ENS 466992011-03-25T15:53:00025 March 2011 15:53:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Potential Unanalyzed Condition Due to Power Level Greater than Limit ENS 465082010-10-23T00:49:00023 October 2010 00:49:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Unanalyzed Condition - Battery Chargers May Lockup During a Design Basis Event ENS 463182010-10-07T18:52:0007 October 2010 18:52:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Degraded Fire Barrier ENS 462612010-09-16T18:43:00016 September 2010 18:43:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Unanalyzed Condition - Degraded Fire Barrier Identified ENS 458552010-04-19T03:25:00019 April 2010 03:25:00 10 CFR 50.72(b)(3)(v)(A), Loss of Safety Function - Shutdown the Reactor, 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 Lco 3.0.3 Entry and Loss of Safety Function Due to Loss of Turbine Building High Energy Line Break Compensatory Measure ENS 455672009-12-14T18:00:00014 December 2009 18:00:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Unanalyzed Condition Related to Certain Fire Conditions ENS 449312009-03-23T22:00:00023 March 2009 22:00:00 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 Unanalyzed Condition for Postulated Missile Hazard That Could Disable Both Trains of Component Cooling ENS 447732009-01-14T17:30:00014 January 2009 17:30:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Manual Actions for Fire Not in Compliance ENS 443792008-07-31T18:45:00031 July 2008 18:45:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Postulated High-Energy Line Break That Could Disable Both Trains of Component Cooling ENS 435922007-08-24T16:30:00024 August 2007 16:30:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Fire Barrier Separation Criteria Not Met for Afwp Rooms ENS 434042007-06-04T21:00:0004 June 2007 21:00:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Unanalyzed Condition Due to Identified Non Compliant Fire Protection Manual Operator Actions ENS 430102006-11-25T01:45:00025 November 2006 01:45:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition Unanalyzed Condition ENS 413772005-02-06T02:46:0006 February 2005 02:46:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition 4160 Volt Relaying and Metering Single Failure Vulnerability 2017-03-20T21:39:00 | |
Retrieved from "https://kanterella.com/w/index.php?title=ENS_50994&oldid=421647"