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| Start date | Reporting criterion | Title | Event description | System | LER | |
|---|---|---|---|---|---|---|
| ENS 51809 | 21 March 2016 01:54:00 | 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded | Technical Specification (Ts) Required Shutdown Due to Pressure Boundary Leakage | During a planned Unit 1 shutdown for a refueling outage, a 0.5 gpm 'pressure boundary leak' was identified on a 1 inch pipe connected to the '1A' RHR-Shutdown Cooling return line by the drywell leak inspection team during a drywell inspection at approximately 15% power. The leak exceeded the TS 3.4.3.2 'Operational Leakage' LCO of no pressure boundary leakage. TS action 'a' was entered which requires to be in at least Hot Shutdown within 12 hours and Cold Shutdown within the next 24 hours. Therefore, the event is reportable within 4 hours per 10CFR50.72(b)(2)(i) due to the initiation of a plant shutdown required by the plant's TS. The event is also reportable within 8 hours per 10CFR50.72(b)(3)(ii) due to an event that resulted in the condition of the nuclear power plant, including its principal safety barriers, being seriously degraded. TS 1.28 defines Pressure Boundary Leakage as leakage through a nonisolable fault in a reactor coolant system component body, pipe wall or vessel wall; therefore, the leak is a 'pressure boundary leak' as defined in TS. The licensee notified the NRC resident Inspector. | Reactor Coolant System | 05000352/LER-2016-003 |
| ENS 50007 | 8 April 2014 10:18:00 | 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown | Shutdown Action Initiated Because Hpci and Rcic Were Simultaneously Inoperable | U1 entered Technical Specification 3.0.3, and initiated actions to reduce power via control rod insertion in preparations to enter startup within the following 6 hours. Entry into Tech Spec 3.0.3 was a result of both HPCI and RCIC injection systems being inoperable at the same time. During startup from the U1 refueling outage, RCIC and HPCI full flow testing was unable to be completed at rated reactor pressure prior to the expiration of the 12 hour allowance per Tech Spec Surveillances 4.7.3.b* and 4.5.1.b.3** respectively. This occurred due to testing issues encountered while attempting to perform the rated pressure pump valve and flow tests. U1 HPCI testing was completed satisfactorily at 0830, and HPCI was restored to operable. Plant shutdown was terminated at 0830 (EDT) as conditions for 3.0.3 no longer existed. The licensee will notify the NRC Resident Inspector. | Control Rod |