ENS 47897
ENS Event | |
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21:13 May 3, 2012 | |
Title | Both Trains of the Controlled Ventilation Area System Inoperable |
Event Description | This is a non-emergency 8 hour9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> notification being made in accordance with 10CFR50.72(b)(3)(ii) Degraded or Unanalyzed Condition and 10CFR50.72(b)(3)(v) Prevented Safety Function. Both trains of the Controlled Ventilation Area System (CVAS) were considered inoperable from 1613 to 1641 CDT on 5/3/2012.
Waterford 3 was performing planned maintenance on CVAS Train A with the train declared inoperable. Operations supervision was informed by maintenance personnel that an electrical conduit near the work area and not related to the work in progress had been found with a conduit connection unthreaded and separated. The contained wires could be seen and appeared intact. Investigation by engineering personnel determined that the conduit was associated with CVAS Train B. Operations declared CVAS Train B inoperable and entered Technical Specification (TS) 3.0.3 at 1613 hours0.0187 days <br />0.448 hours <br />0.00267 weeks <br />6.137465e-4 months <br />. Operations personnel were already restoring CVAS Train A following completion of maintenance. After performing the planned retest, Operations declared CVAS Train A operable and exited TS 3.0.3 at 1641 hours0.019 days <br />0.456 hours <br />0.00271 weeks <br />6.244005e-4 months <br />. No actions were taken to commence a power reduction or reactor shutdown. The CVAS is required following a design basis accident to draw all exhaust air from the CVAS areas of the Reactor Auxiliary Building through HEPA and charcoal filters before discharge to the atmosphere. The CVAS areas contain equipment such as the shutdown cooling heat exchangers, safety injection pumps and other areas with containment penetrations. The CVAS is credited in accident analysis for limiting the radiological release under a Loss of Coolant Accident condition. Following repair of the conduit connection, Operations declared CVAS Train B operable at 1956 hours0.0226 days <br />0.543 hours <br />0.00323 weeks <br />7.44258e-4 months <br />. Waterford 3 remained stable at 100% power during the condition. Both trains of offsite and onsite electrical sources, ECCS, and Containment Cooling safety systems remained operable during the condition. The licensee notified the NRC Resident Inspector.
This is a non-emergency notification from Waterford 3 retracting a previous notification. On 5/3/2012 at 2107 EDT, Waterford 3 communicated Notification Message EN 47897, pursuant to 10 CFR 50.72(b)(2)(ii), Degraded or Unanalyzed Condition and 10 CFR 50.72(b)(3)(v), Prevented Safety Function, stating that both trains of the Controlled Ventilation Area System (CVAS) were considered inoperable from 1613 to 1641 CDT on 5/3/2012. Subsequent engineering evaluation has determined that the as-found condition would not cause the inoperability of CVAS Train B. With one train operable, the plant remained within analyzed conditions and capable of fulfilling safety functions. As such, no condition existed which required reporting. Based on this information, Waterford 3 is retracting notification message EN 47897. The licensee has notified the NRC Resident Inspector. Notified the R4DO (Clark). |
Where | |
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Waterford Louisiana (NRC Region 4) | |
Reporting | |
10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded 10 CFR 50.72(b)(3)(v)(C), Loss of Safety Function - Release of Radioactive Material | |
Time - Person (Reporting Time:+-0.1 h-0.00417 days <br />-5.952381e-4 weeks <br />-1.3698e-4 months <br />) | |
Opened: | Jesse Bohnenkamp 21:07 May 3, 2012 |
NRC Officer: | Donald Norwood |
Last Updated: | Jun 29, 2012 |
47897 - NRC Website | |
Unit 3 | |
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Reactor critical | Critical |
Scram | No |
Before | Power Operation (100 %) |
After | Power Operation (100 %) |
Waterford with 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded, 10 CFR 50.72(b)(3)(v)(C), Loss of Safety Function - Release of Radioactive Material | |
WEEKMONTHYEARENS 568342023-11-05T16:33:0005 November 2023 16:33:00
[Table view]10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded Degraded Condition - Two Steam Generator Tube Failures Identified ENS 538372019-01-18T19:33:00018 January 2019 19:33:00 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded Reactor Coolant System Weld Does Not Meet Acceptance Criteria ENS 538342019-01-17T06:00:00017 January 2019 06:00:00 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded Relevant Indication of Degraded Condition ENS 478972012-05-03T21:13:0003 May 2012 21:13:00 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded, 10 CFR 50.72(b)(3)(v)(C), Loss of Safety Function - Release of Radioactive Material Both Trains of the Controlled Ventilation Area System Inoperable ENS 455262009-11-29T05:44:00029 November 2009 05:44:00 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded Containment Minimum Pathway Leak Rate Was Exceeded ENS 416592005-05-02T12:55:0002 May 2005 12:55:00 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded During Steam Generator Tube Inspection - Greater than 1% (106 Tubes) of the Tubes Were Found Defective ENS 416172005-04-19T22:51:00019 April 2005 22:51:00 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded Degraded Condition Found at Waterford Unit 3 ENS 402952003-11-04T06:00:0004 November 2003 06:00:00 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded Number of Steam Generator Tubes Requiring Repair Exceeds 1 Percent ENS 402782003-10-27T01:00:00027 October 2003 01:00:00 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded Indication of Leakage ENS 402772003-10-25T04:00:00025 October 2003 04:00:00 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded Degradation of the Reactor Coolant System (Rcs) Pressure Boundary 2023-11-05T16:33:00 | |