05000325/LER-2022-001, High Pressure Coolant Injection (HPCI) Inoperable
| ML22255A164 | |
| Person / Time | |
|---|---|
| Site: |  |
| Issue date: | 09/12/2022 |
| From: | Krakuszeski J Duke Energy Progress |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| RA-22-0242 LER 2022-001-00 | |
| Download: ML22255A164 (5) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(v), Loss of Safety Function |
| 3252022001R00 - NRC Website | |
text
~~ DUKE
~ ENERGY September 12, 2022 Serial: RA-22-0242 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555
Subject:
Brunswick Steam Electric Plant, Unit No. 1 Renewed Facility Operating License No. DPR-71 Docket No. 50-325 Licensee Event Report 1-2022-001 John A. Krakuszeski Vice President Brunswick Nuclear Plant 8470 River Rd SE Southport, NC 28461 o: 910.832.3698 10 CFR 50.73 In accordance with the Code of Federal Regulations, Title 10, Part 50.73, Duke Energy Progress, LLC, is submitting the enclosed Licensee Event Report (LER). This report fulfills the requirement for a written report within sixty (60) days of a reportable occurrence.
This document contains no regulatory commitments.
Please refer any questions regarding this submittal to Mr. Mark DeWire, Manager - Nuclear Support Services, at (910) 832-6641.
Sincerely, John A. Krakuszeski SBY/sby
Enclosure:
Licensee Event Report
U.S. Nuclear Regulatory Commission Page 2 of 2 cc (with enclosure):
Ms. Laura Dudes, NRC Regional Administrator, Region II Mr. Luke Haeg, NRC Project Manager Mr. Gale Smith, NRC Senior Resident Inspector Chair - North Carolina Utilities Commission
Abstract
At 20:20 Eastern Daylight Time (EDT) on July 15, 2022, with Unit 1 in Mode 1 at approximately 96% power for planned maintenance on the 1A Condensate Deep-bed Demineralizer (unrelated to this event), the High Pressure Coolant Injection (HPCI) system was declared inoperable upon discovering the HPCI flow controller without power.
The HPCI flow controller lost power as a result of an intermittent connection in the flow controller fuse holder. The fuse was secured in the fuse holder and HPCI was declared operable on July 16, 2022, at 12:10 EDT following associated post maintenance testing. The Reactor Core Isolation Cooling (RCIC) System and Automatic Depressurization System (ADS) remained operable during this event.
There was no impact on the health and safety of the public or plant personnel. The safety significance of this event is minimal.
This event is being reported in accordance with 10 CFR 50.73(a)(2)(v)(D).
(See Page 3 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 3 of 3 The safety significance of this event is minimal.
Corrective Actions
The fuse was secured in the fuse holder and the Unit 1 HPCI system was declared operable on July 16, 2022, at 12:10 EDT following associated post maintenance testing. Also, as part of an extent of condition review, the Unit 2 HPCI flow controller fuse holder was ensured to be secured and, since RCIC uses the same made/model controller, the Unit 1 and Unit 2 RCIC flow controller fuse holders will be checked to ensure tightness.
In addition, instructions will be added to the associated maintenance procedure to check the fuse holder tightness prior to returning the HPCI and RCIC flow controllers to service following replacement and calibration. This action is planned to be completed by November 14, 2022.
Any revisions to corrective actions will be made in accordance with the sites corrective action program.
Previous Similar Events
A review of events for the past three years identified the following previous similar events related to HPCI inoperability.
Event Notification 54116, completed on June 13, 2019, reported HPCI System inoperability due to the required response time not being met during routine testing. This event was the result of the HPCI turbine experiencing an overspeed trip during the initial ramp up to achieve rated conditions. In this event, the overspeed trip was caused by a momentary failure of the Electric Governor - Remote (EG-R) as a result of internally generated debris causing binding within the EG-R and preventing proper speed control.
Event Notification 55780, completed on March 9, 2022, reported Unit 2 HPCI System inoperability following evaluation of routine HPCI surveillance testing data indicating that the required response time for reaching rated conditions was not met.
It was determined that this was caused by sluggish operation (i.e., sticking) of the remote servo associated with the HPCI turbine speed control system. Event Notification 55780 was retracted on May 4, 2022, after it was determined that the required response time was overly conservative for assuring the safety function of the system could be fulfilled and there was not a condition that could have prevented the system from fulfilling the safety function.
The corrective actions associated with these previous similar events could not have reasonably been expected to prevent the condition reported herein.
Commitments
No regulatory commitments are contained in this report.