05000369/LER-2023-001, Automatic Actuation of the 1A Motor Driven Auxiliary Feedwater Pump Due to Human Error
| ML23347A120 | |
| Person / Time | |
|---|---|
| Site: | McGuire  |
| Issue date: | 12/13/2023 |
| From: | Pigott E Duke Energy Carolinas |
| To: | Office of Nuclear Reactor Regulation, Document Control Desk |
| References | |
| RA-23-0322 LER 23-001-00 | |
| Download: ML23347A120 (1) | |
| Event date: | |
|---|---|
| Report date: | |
| 3692023001R00 - NRC Website | |
text
£ 9, DUKE
~ ENERGY Serial No: RA-23-0322 December 13, 2023 U.S. Nuclear Regulatory Commission Washington, D.C. 20555 ATTENTION: Document Control Desk
Subject:
Duke Energy Carolinas, LLC McGuire Nuclear Station, Unit 1 Docket No. 05000369 Renewed License No. NPF-9 Licensee Event Report 2023-001-00 Nuclear Condition Report Number 02491016 Edward R. Pigott Site Vice President McGuire Nuclear Station Duke Energy MG01VP 112700 Hagers Ferry Road Huntersville, NC 28078 o: 980.875.4805 Edward.Pigott@duke-energy.com 10 CFR 50.73 Pursuant to 10 CFR 50.73 Section (a)(2)(iv)(A), attached is Unit 1 Licensee Event Report (LER) 2023-001-00, regarding automatic actuation of the 1A Motor Driven Auxiliary Feedwater Pump due to human error.
This event is considered to have no significance with respect to the health and safety of the public. There are no regulatory commitments contained in this LER.
If questions arise regarding this LER, please contact Jeff Sanders at 980-875-4680.
Sincerely, Edward R. Pigott Duke Energy McGuire Nuclear Station Site Vice President Attachment
U.S. Nuclear Regulatory Commission RA-23-0322 Page2 cc:
Laura A. Dudes Administrator Region II U.S. Nuclear Regulatory Commission Marquis One Plaza 245 Peachtree Center Avenue NE Suite 1200, 30303-1257 J. Klos Project Manager (McGuire)
U.S. Nuclear Regulatory Commission Mail Stop O-9-E3 11555 Rockville Pike Rockville, MD 20852 Chris Safouri NRG Senior Resident Inspector McGuire Nuclear Station
Abstract
On October 18, 2023, an actuation of the A Train Auxiliary Feedwater (AFW) pump occurred while Unit 1 was in Mode 5 during a planned refueling outage. Maintenance technicians were performing PT/0/A/4600/012 A (Train A Reactor Trip Breakers Actuating Device Operational Test for Manual Trip Function) and removed the incorrect fuse in the 1A Solid State Protection System (SSPS) cabinet, temporarily deenergizing Train A SSPS Slave Relays. This caused the 1A AFW Auto-Start Defeat circuit to reset, and in turn, start the 1A AFW pump. The Automatic Recirculation Valve (ARV) provided the required flow path for pump protection. Auxiliary Feedwater was not supplied to the respective Steam Generators due to the motor operated discharge isolation valves (MOVs) being closed as required for current plant conditions.
At the time of the 1A AFW actuation, the Main Feedwater (MFW) pumps were in a tripped condition, and decay heat removal was being provided by the 1A Residual Heat Removal (RHR) System. Both MFW pumps being in tripped status provided the logic for the AFW actuation signal once the 1A AFW Auto-Start Defeat circuit was reset.
Corrective actions included personnel accountability and reinforcement of human performance tools.
(See Page 2 for required number of digits/characters for each block)
(See NUREG-1022, R.3 for instruction and guidance for completing this form http://www.nrc.gov/reading-rm/doc-collections/nuregs/staff/sr1022/r3/)
Page 4 of 4 CAUSAL FACTORS:
Causal factors include inadequate human performance behaviors specifically related to procedure use and adherence and verification practices. Additionally, maintenance leadership did not effectively reinforce the importance of correct human performance behaviors in accordance with site standards.
CORRECTIVE ACTIONS
Immediate:
- 1. Operations verified a satisfactory pump start including an adequate recirculation flow path of the 1A Auxiliary Feedwater pump.
Planned:
- 1. Appropriate accountability and remediation actions will be performed for the technicians involved.
- 2. Maintenance leadership will perform deliberate observations to reinforce adherence to site human performance standards.
SAFETY ANALYSIS
At the time of the AFW actuation, the MFW system was shut down and the steam generators were not being relied upon for heat removal. Decay heat removal was being provided by the 1A RHR system. The plant was in Mode 5 making preparations to enter Mode 4 from an extended refueling outage with new fuel in the reactor and therefore, low decay heat. The AFW actuation signal that caused the 1A AFW actuation was not required to be operable in Mode 5.
In conclusion, this event is considered to be of very low safety significance. The 1A AFW system responded as designed to the inadvertent actuation. This event had no impact on the health and safety of the public.
ADDITIONAL INFORMATION
A search of previous similar events over the past three years revealed no other AFW automatic actuation resulting from human performance error; therefore, this event is not recurring.