05000416/LER-2017-006
| 10-12-2017 | On August 22, 2017 at 2321 hours0.0269 days <br />0.645 hours <br />0.00384 weeks <br />8.831405e-4 months <br /> central daylight time, Grand Gulf Nuclear Station entered Technical Specification (TS) conditions for three Limiting Condition for Operations (LCOs) not met due to Residual Heat Removal 'A' (RHR A) being declared inoperable. Entergy Operations Inc. (Entergy) made the decision to shut down the plant based on the results of troubleshooting performed on the RHR A pump. The A RHR pump TS differential pressure was out of specification (low) and could not be returned to acceptable limits.
Grand Gulf Nuclear Station initiated plant shutdown required by Technical Specifications 3.5.1, 3.6.1.7, and 3.6.2.3 at 1200 hours0.0139 days <br />0.333 hours <br />0.00198 weeks <br />4.566e-4 months <br /> CDT on August 29, 2017, due to expected restoration of RHR A exceeding the completion time of 7 days prior to restoring Operability. The shutdown was completed and entry into MODE 3 occurred at 2217 hours0.0257 days <br />0.616 hours <br />0.00367 weeks <br />8.435685e-4 months <br /> CDT on August 29, 2017. The cause is under investigation and this LER will be supplemented upon completion of the causal analysis. Corrective Actions included the replacement of the A RHR pump and the successful retesting of the. A RHR pump and restoration of the pump to operable status. This condition is reportable as a completion of a plant shutdown required by the TS. (4-2017) 366A U.S. NUCLEAR REGULATORY COMMISSION ContentsCONTINUATION SHEET(See NUREG-1022, R.3 for instruction and guidance for completing this form htio://www.nrcoovireadino-rm/dcc-collectionenureosistafffsr1022;r31 APPROVED BY OMB: NO. 3150-0104 EXPIRES: 3/31/2020 Reported lessons learned are incorporated into the licensing process and fed back to Industry. Send comments regarding burden estimate to the Information Services Branch (T-2 F43), U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, or by e-mail to Regulatory Affairs, NEOB-10202, (3150-0104), Office of Management and Budget, Washington, DC 20503. If a means used to impose an information collection does not display a currently valid OMB control number, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection. Grand Gulf Nuclear Station, Unit 1 05000 416 3. LER NUMBERDescription On August 22, 2017 at 2321 hours0.0269 days <br />0.645 hours <br />0.00384 weeks <br />8.831405e-4 months <br /> central daylight time (CDT), Grand Gulf Nuclear Station entered Technical Specification (TS) conditions for three Limiting Condition for Operations (LCOs) not met due to Residual Heat Removal [BO] 'A' (RHR A) being declared inoperable. LCOs not met: 1) TS 3.5.1 for one low pressure ECCS injection/spray subsystem. 2) TS 3.6.1.7 for one RHR containment spray subsystem, and 3) TS 3.6.2.3 for one RHR suppression pool cooling subsystem. Entergy Operations Inc. (Entergy) made the decision to shut down the plant based on the results of troubleshooting performed on the RHR A pump. Grand Gulf Nuclear Station initiated plant shutdown required by Technical Specifications 3.5.1, 3.6.1.7, and 3.6.2.3 at 1200 hours0.0139 days <br />0.333 hours <br />0.00198 weeks <br />4.566e-4 months <br /> CDT on August 29, 2017, due to expected restoration of RHR A exceeding the TS completion time of 7 days prior to restoring Operability. The shutdown was completed and entry into MODE 3 occurred at 2217 hours0.0257 days <br />0.616 hours <br />0.00367 weeks <br />8.435685e-4 months <br /> CDT on August 29, 2017. REPORTABILITYEntergy completed Event Notification 52936 notifying the Nuclear Regulatory Commission of the commencement of a plant shutdown in accordance with 10CFR50.72(b)(2)(i), due to the anticipated inability to complete the required A RHR Pump repairs prior to exceeding the TS LCO time limits. The completion of the shutdown reported in Event Notification 52936 is reportable in accordance with 10CFR50.73(a)(2)(i)(A), the completion of any nuclear plant shutdown required by the plant's Technical Specifications. LCOs not met: 1) TS 3.5.1 for one low pressure ECCS [BO] injection/spray subsystem. 2) TS 3.6.1.7 for one RHR containment spray subsystem, and 3) TS 3.6.2.3 for one RHR suppression pool cooling subsystem. CAUSEThe A RHR pump TS differential pressure was out of specification (low) and could not be returned to acceptable limits prior to exceeding the 7 day limiting condition for operation time. The A RHR pump was shipped to a vendor for the determination of the cause of the A RHR pump being out of specification limits. This causal analysis is not anticipated to be completed prior to the 60 day report time for this licensee event report (LER). This LER will be supplemented upon completion of the causal analysis. CORRECTIVE ACTIONSReplacement of the A RHR pump. Successful retesting of the A RHR pump and restoration of the pump to operable status. NRC FORM(4-2017) 366A U.S. NUCLEAR REGULATORY COMMISSION CONTINUATION SHEET(See NUREG-1022, R.3 for instruction and guidance for competing thIs.form httplAvww.nrc.dovireadino-rm(doc-coRectionsinurectsistaff/sr1022/r3/) APPROVED BY OMB: NO. 3150-0104 EXPIRES: 3/31/2020 Reported lessons learned are incorporated into the licensing process and fed back to industry. Send comments regarding burden estimate to the Information Services Branch (T-2 F43), U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, or by e-mail to Regulatory Affairs, NEOB-10202, (3150-0104), Office of Management and Budget, Washington, DC 20503. If a means used to impose an information colIection does not display a currently valid OMB con:rol number, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection. 05000 416 SAFETY SIGNIFICANCEThe event posed no threat to the health and safety of the general public or to nuclear safety as safety-systems performed as designed. No Technical Specification safety limits were violated. Industrial safety was not challenged, and there was no potential or actual radiological release during the event. PREVIOUS SIMILAR OCCURRENCESRemoval Pump The causes and corrective actions associated with these previous similar events was reviewed and it is believed that the corrective actions could not have prevented the cause of this event. |
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| Grand Gulf Nuclear Station, Unit 1 | |
| Event date: | 8-29-2017 |
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| Report date: | 10-12-2017 |
| Reporting criterion: | 10 CFR 50.73(a)(2)(i)(A), Completion of TS Shutdown |
| Initial Reporting | |
| ENS 52936 | 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown |
| 4162017006R00 - NRC Website | |
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