05000250/LER-2021-003, Regarding Auxiliary Feedwater Actuation Due to Feedwater Isolation During Plant Shutdown
| ML21336A205 | |
| Person / Time | |
|---|---|
| Site: | Turkey Point  |
| Issue date: | 12/02/2021 |
| From: | Pearce M Florida Power & Light Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| L-2021-229 LER 2021-003-00 | |
| Download: ML21336A205 (1) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(iv)(A), System Actuation 10 CFR 50.73(a)(2) |
| 2502021003R00 - NRC Website | |
text
U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D.C. 20555-0001 RE: Turkey Point Unit 3 Docket No. 50-250 Reportable Event: 2021-003-00 Date of Event: October 9, 2021 10 CFR 50.73 L-2021-229 December 2, 2021 Title: Auxiliary Feedwater Actuation due to Feedwater Isolation During Plant Shutdown The attached Licensee Event Report 05000250/2021-003-00 is submitted pursuant to 10 CFR 50.73 (a)(2)(iv)(A), due to automatic actuation of the Auxiliary Feedwater System.
If there are any questions, please call Mr. Robert Hess at 305-246-4112 or e-mail Ro bert.Hess@fpl.com.
Sincerely, wM,{J~
Michael Pearce Site Vice President - Turkey Point Nuclear Plant Florida Power & Light Company Attachments: USNRC Forms 366 and 366A, current revision cc: USNRC Senior Resident Inspector, Turkey Point Plant USNRC Regional Administrator, Region II Florida Power & Light Company 9760 SW 344th St., Homestead, FL 33035
Abstract
Turkey Point Unit 3 250 3
Auxiliary Feedwater Actuation due to Feedwater Isolation During Plant Shutdown 10 09 2021 2021 003 00 12 02 2021 Mode 3 0
David Stoia - Licensing Engineer 305-246-6538 B
SJ FCV Y
On 10/9/2021 at 03:00, with Unit 3 in Mode 3 at 0% power, an actuation of the Auxiliary Feedwater (AFW) system occurred when level in the 3A Steam Generator increased to 80%, causing a Feedwater isolation signal, which tripped the running Steam Generator Feedwater Pump. The AFW system automatically started in response to the trip of the last running feedwater pump.
All systems responded as designed to the 3A S/G high level condition. This event is reportable pursuant to 10 CFR 50.73(a)(2)
(iv)(A) as a condition that resulted in the auto-start of the AFW system.
~~--~-
\\ ~)
I ID Page of 05000-
- 3. LER NUMBER YEAR SEQUENTIAL NUMBER REV NO.
CORRECTIVE ACTIONS
- 1. FCV-3-478 was overhauled to correct the excessive seat leakage. PM frequency returned to every 4 outages.
- 2. Performed borescope inspection of MOV-3-1407 seating surfaces and verified no visible deficiencies.
- 3. Maintenance strategies and valve overhaul PM frequencies will be reviewed for adequacy.
- 4. A revision to the Operating Procedure was issued that provides guidance to Operations for closing the manual isolation valves if excessive seat leakage becomes evident during plant startup and shutdown.
ADDITIONAL INFORMATION
EIIS Codes are shown in the format [IEEE system identifier, component function identifier, second component function identifier (if appropriate)].
SIMILAR EVENTS
A review of automatic AFW start events over the previous 5 years was performed to identify similar events or patterns.
Although automatic AFW actuation normally occurs in Mode 3 after a trip from higher power levels due to S/G level shrink, these events are not caused or influenced by valve seat leakage. No events were identified that involved an automatic AFW actuation that was potentially caused by feedwater flow control valve seat leakage.
3 3
Turkey Point Unit 3 250 2021 003 00 r;;)"all("Ot,<,t
.. ~
"h,.,
i
=
i..,.,
.. ~"
- f!*
I I
I I I I D