ENS 51348
ENS Event | |
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12:40 Aug 26, 2015 | |
Title | Both Emergency Diesel Generators Declared Inoperable |
Event Description | This is a non-emergency notification from Waterford 3. On August 26, 2015, at 0111 CDT, Emergency Diesel Generator (EDG) 'A' was declared inoperable following a trip of EDG 'A' on Generator Differential. Technical Specification (TS) 3.8.1.1 actions b. and d. were entered. EDG 'A' was being routinely run in accordance with OP-903-115, 'Train A Integrated Emergency Diesel Generator/Engineering Safety Features Test', Section 7.4, '24 hr EDG A Run with Subsequent Diesel Start' to satisfy Technical Specification Surveillance Requirement 4.8.1.1.2 6. EDG 'B' was subsequently started per TS 3.8.1.1 action b. (1). At 0740 CDT, EDG 'B' was declared inoperable and TS 3.8.1.1 f. was entered due to the exhaust fan not starting when the diesel engine was started.
Troubleshooting determined that the EDG B exhaust fan did not start due to HVR-501B (EG B ROOM OUTSIDE AIR INTAKE DAMPER) not opening. Action was taken to isolate air and fail HVR-501B to its open safety position. At 1001 CDT, EDG 'B' was declared operable and TS 3.8.1.1.f. was exited following verification of proper operation of the EDG 'B' exhaust fan. Waterford 3 is currently in TS 3.8.1.1 actions b. and d. Actions to verify a temporary EDG is available and restore EDG 'A' to operable status are in progress. This event is reportable pursuant to 10 CFR 50.72(b)(3)(v) (A) and 10 CFR 50.72 (b)(3)(v) (D), 'event or condition that could have prevented fulfillment of a safety function of structures or systems that are needed to (A) shut down the reactor and maintain it in a safe shutdown condition' and (D) 'mitigate the consequences of an accident due to both emergency diesel generators being inoperable.' The NRC Resident Inspector has been notified.
The following is a correction to a non-emergency event notification from Waterford 3 originally made on 8/26/2015: On August 26, 2015, at 0111 CDT, Emergency Diesel Generator (EDG) 'A' was declared inoperable following a trip of EDG 'A' on Generator Differential. Technical Specification (TS) 3.8.1.1 actions b and d were entered. EDG 'A' was being routinely run in accordance with OP-903-115, 'Train A Integrated Emergency Diesel Generator/Engineering Safety Features Test,' Section 7.4, '24 hr EDG A Run with Subsequent Diesel Start' to satisfy Technical Specification Surveillance Requirement 4.8.1.1.2(e)6. EDG 'B' was subsequently started per TS 3.8.1.1 action b.(1). At 0740 CDT, EDG 'B' was declared inoperable and TS 3.8.1.1 f was entered due to the room exhaust fan not starting when the diesel engine was started. Troubleshooting determined that the EDG B room exhaust fan did not start due to HVR-501B (EDG B ROOM OUTSIDE AIR INTAKE DAMPER) not opening. Action was taken to isolate air and fail HVR-501B to its open safety position. At 1001 CDT, EDG 'B' was declared operable and TS 3.8.1.1.f was exited following verification of proper operation of the EDG 'B' room exhaust fan. Waterford 3 is currently in TS 3.8.1.1 actions b and d. Actions to verify a temporary EDG is available and restore EDG 'A' to operable status are in progress. This event is reportable pursuant to 10 CFR 50.72(b)(3)(v)(A) and 10 CFR 50.72(b)(3)(v)(D), Event or Condition that Could Have Prevented Fulfillment of a Safety Function of structures or systems that are needed to (A) shut down the reactor and maintain it in a safe shutdown condition and (D) mitigate the consequences of an accident due to both emergency diesel generators being inoperable. The NRC Resident Inspector has been notified. Notified R4DO (Warnick) |
Where | |
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Waterford Louisiana (NRC Region 4) | |
Reporting | |
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 | |
Time - Person (Reporting Time:+3.12 h0.13 days <br />0.0186 weeks <br />0.00427 months <br />) | |
Opened: | Maria Zamber 15:47 Aug 26, 2015 |
NRC Officer: | Jeff Herrera |
Last Updated: | Aug 31, 2015 |
51348 - NRC Website | |
Unit 3 | |
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Reactor critical | Critical |
Scram | No |
Before | Power Operation (100 %) |
After | Power Operation (100 %) |