17:10 Jan 1, 2022
High Pressure Core Spray System Declared Inoperable
The Licensee provided the following information via fax:
During performance of a surveillance of the High Pressure Core Spray (HPCS) service water system on January 1, 2022, the HPCS system was declared inoperable for performance of the surveillance. During the surveillance, pump discharge pressure and flow were above the action range curve specified in the surveillance. For the given flow rate, pump discharge pressure was too high. This condition prevents declaring the HPCS service water system and HPCS system operable. The HPCS service water and HPCS systems remain inoperable.
The station entered Technical Specification (TS) 3.7.2.A and TS 3.5.1.B at 0910 [PST] on January 1, 2022. In accordance with TS 3.5.1.B, the Reactor Core Isolation Cooling (RCIC) system was verified to be operable. TS 3.5.1 Action B provides a 14-day completion time to restore HPCS to an operable status.
All other Emergency Core Cooling systems (ECCS) are operable. This event is being reported as an event or condition that could have prevented the fulfillment of a safety function credited for mitigating the consequences of an accident per 10 CFR 50.72(b)(3)(v)(D). The HPCS system is a single train system at Columbia.
The NRC resident has been notified.
The following additional information was obtained from the licensee in accordance with Headquarters Operations Officers Report Guidance:
The licensee is investigating the cause of the high pump discharge pressure and verifying instrumentation accuracy.
This Notification is to retract EN 55682, Unplanned High Pressure Core Spray (HPCS) Inoperability. On 1/1/2022 at [1735 EST], Columbia Generating Station notified the NRC under 10 CPR 50.72(b)(3)(v)(D) of the inoperability of a single train of safety system (HPCS) for performance of the surveillance. During the surveillance pump discharge pressure and flow were above the action range curve specified in the surveillance.
Engineering performed an analysis of this event and concluded the HPCS was operable during the event and would have performed its required safety function.
The results of initial IST testing of HPCS-P-2 via OSP-SW/IST-Q703 on 01/01/22 resulted in measured parameters falling outside of the acceptable range specified for this pump. Systematic error was suspected as the cause of the failure and the test was reperformed following taking actions to eliminate the suspected systematic errors. The second performance of the test on 01/01/22 resulted in acceptable pump performance. Evidence exists that the initial performance of the test failed due to imprecise averaging techniques due to difficulties in averaging continuously changing values on the test instrument. The second performance of OSP-SW/IST-Q703 should be considered a successful test and the test of record as the systematic error was eliminated and measured parameters are considered valid.
The NRC Resident Inspector has been notified.The HOO notified R4DO (Rolando-Otero).
|Columbia Generating Station |
Washington (NRC Region 4)
|10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident|
|Time - Person (Reporting Time:+0.42 h0.0175 days <br />0.0025 weeks <br />5.75316e-4 months <br />)|
17:35 Jan 1, 2022
|NRC Officer:||Karen Cotton-Gross|
|Last Updated:||Jan 6, 2022|
|55682 - NRC Website|