ENS 46817
ENS Event | |
|---|---|
21:16 Mar 15, 2011 | |
| Title | Invalid Actuation of the Standby Service Water Pump |
| Event Description | On March 15, 2011 with Beaver Valley Power Station Unit 2 in Mode 6 during a scheduled refueling outage, the 'A' Standby Service Water (SWE) pump 2SWE-P21A automatically started at 1716 hours0.0199 days <br />0.477 hours <br />0.00284 weeks <br />6.52938e-4 months <br /> when electrical power was removed from the Secondary Process Rack 'A' . The removal of power from the process rack caused pressure transmitter 2SWS-PT113A (Service Water Pump Discharge Pressure Transmitter) to read low resulting in an invalid automatic start of pump 2SWE-P21A. As a result of the automatic start of the SWE pump, the SWE pump discharge isolation valve (2SWE-MOV116A) also opened to provide a flow path from the SWE header to the main service water supply header. The SWE pump is designed to automatically start on a low service water header pressure (i.e. < 34 psig). At the time of the actuation, the service water header pressure was stable at 93 psig. This invalid actuation resulted in a successful start of the Train 'A' SWE system which functioned properly. Plant operators secured the SWE pump after determining that the pump start was invalid and entered the issue into the corrective action program for evaluation.
The SWE system is required by the Beaver Valley Unit 2 Licensing Requirements Manual requirement number 3.7.5 to be Functional in plant operating Modes 1, 2, 3, and 4. The SWE system is not normally in operation and serves as a backup cooling water supply on a loss of the main intake structure. The non-safety related automatic start of the SWE pump on low service water pressure is provided to prevent an inadvertent plant trip on a loss of a running service water pump and is not required for the design basis event. The plant was in Mode 6 when the invalid actuation occurred. The automatic start of the SWE pump was not initiated in response to any plant event. This event is reportable 10 CFR 50.73(a)(2)(iv)(A) since it involved an actuation of an emergency service water system as per 10 CFR 50.73(a)(2)(iv)(B)(9). Pursuant to 10 CFR 50.73(a)(1), this event is being reported via this telephone notification, in lieu of a written Licensee Event Report, since the automatic actuation of the Train 'A' SWE was invalid. The licensee has notified the NRC Resident Inspector. |
| Where | |
|---|---|
Beaver Valley  Pennsylvania (NRC Region 1) | |
| Reporting | |
| 10 CFR 50.73(a)(1), Submit an LER, Invalid Actuation | |
| Time - Person (Reporting Time:+1189.32 h49.555 days <br />7.079 weeks <br />1.629 months <br />) | |
| Opened: | David Haser 10:35 May 4, 2011 |
| NRC Officer: | Howie Crouch |
| Last Updated: | May 4, 2011 |
| 46817 - NRC Website | |
WEEKMONTHYEARENS 556022021-09-30T14:07:00030 September 2021 14:07:00
[Table view]10 CFR 50.73(a)(1), Submit an LER 60-DAY Optional Telephonic Notification for an Invalid Emergency Diesel Generator Actuation ENS 468172011-03-15T21:16:00015 March 2011 21:16:00 10 CFR 50.73(a)(1), Submit an LER Invalid Actuation of the Standby Service Water Pump ENS 468162011-03-07T15:18:0007 March 2011 15:18:00 10 CFR 50.73(a)(1), Submit an LER Invalid Actuation of the Auxiliary Feedwater System ENS 450992009-05-06T17:52:0006 May 2009 17:52:00 10 CFR 50.73(a)(1), Submit an LER Automatic Actuation of Rps, Eccs and Edg Generated by an Invalid Actuation Signal ENS 450012009-04-20T05:53:00020 April 2009 05:53:00 10 CFR 50.73(a)(1), Submit an LER Unexpected Start of the Steam Driven Auxiliary Feedwater Pump During Plant Cooldown ENS 446612008-10-16T14:07:00016 October 2008 14:07:00 10 CFR 50.73(a)(1), Submit an LER Invalid Actuation of Steam Driven Aux Feed Pump ENS 411192004-09-10T21:30:00010 September 2004 21:30:00 10 CFR 50.73(a)(1), Submit an LER Invalid Actuation of Steam Driven Auxiliary Feedwater Pump 2021-09-30T14:07:00 | |