ENS Event | |
|---|---|
23:47 May 25, 2017 | |
| Title | Invalid High Pressure Core Spray (Hpcs) System Actuation in Mode 5 |
| Event Description | At 1647 [PDT] on May 25, 2017, during the performance of a post-maintenance test for replacement of a Reactor Pressure Vessel (RPV) low water level 3 indicator switch (MS-LIS-24A), a pressure perturbation in the common pressure reference line resulted in tripping of the RPV Level 2 instruments and an unplanned start of High Pressure Core Spray (HPCS) pump (HPCS-P-1) and its supporting emergency diesel (DG3). The Reactor Pressure Vessel was flooded up during the refueling outage, thus, the actuations of the HPCS pump and its supporting emergency diesel (DG3) were unplanned and invalid. The HPCS pump did not inject into the RPV due to the RPV level being above Level 8 which is an interlock to close the HPCS RPV injection valve (HPCS-V-4).
During the event, the single train HPCS system initiated normally but did not inject into the reactor pressure vessel as expected due to flooded-up conditions of the reactor pressure vessel for refueling outage activities. The emergency diesel generator started normally in response to the initiation signal of HPCS. Both HPCS and the emergency diesel generator functioned successfully. All systems responded in conformance with their design and there was no safety significance associated with this event. At the time of the event, the licensee notified the NRC Resident [Inspector]. |
| Where | |
|---|---|
Columbia Generating Station  Washington (NRC Region 4) | |
| Reporting | |
| 10 CFR 50.73(a)(1), Submit an LER, Invalid Actuation | |
| Time - Person (Reporting Time:+1429.82 h59.576 days <br />8.511 weeks <br />1.959 months <br />) | |
| Opened: | Sandra Christianson 13:36 Jul 24, 2017 |
| NRC Officer: | Dong Park |
| Last Updated: | Jul 24, 2017 |
| 52869 - NRC Website | |
WEEKMONTHYEARENS 566252023-05-17T10:39:00017 May 2023 10:39:00
[Table view]10 CFR 50.73(a)(1), Submit an LER 60-DAY Optional Telephonic Notification for an Invalid Actuation of an Emergency AC Electrical Power System ENS 528692017-05-25T23:47:00025 May 2017 23:47:00 10 CFR 50.73(a)(1), Submit an LER Invalid High Pressure Core Spray (Hpcs) System Actuation in Mode 5 ENS 494602013-08-23T14:54:00023 August 2013 14:54:00 10 CFR 50.73(a)(1), Submit an LER 60-Day Optional Telephonic Notification for an Invalid Primary Containment Isolation Valve Actuation ENS 481392012-05-31T12:35:00031 May 2012 12:35:00 10 CFR 50.73(a)(1), Submit an LER 60-Day Optional Telephonic Notification for an Invalid Primary Containment Isolation Valve Actuation ENS 469772011-04-23T15:14:00023 April 2011 15:14:00 10 CFR 50.73(a)(1), Submit an LER Invalid Primary Containment Isolation System Actuation Due to Unrecognized Design Conflict ENS 469722011-04-21T20:10:00021 April 2011 20:10:00 10 CFR 50.73(a)(1), Submit an LER Invalid Primary Containment Isolation System Actuation Due to Conflicting Work Activities ENS 468972011-04-01T04:28:0001 April 2011 04:28:00 10 CFR 50.73(a)(1), Submit an LER 60-Day Telephonic Notification of Invalid Specified System Actuation 2023-05-17T10:39:00 | |