05000389/LER-2022-001, Reactor Shutdown Required by Technical Specifications Due to a Misaligned Control Element Assembly

Reactor Shutdown Required by Technical Specifications Due to a Misaligned Control Element Assembly

ML22063A075
Person / Time
Site:	Saint Lucie
Issue date:	03/04/2022
From:	Deboer D Florida Power & Light Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
L-2022-024 LER 2022-001-00
Download: ML22063A075 (4)

LER-2022-001, Reactor Shutdown Required by Technical Specifications Due to a Misaligned Control Element Assembly

Event date:
Report date:
Reporting criterion:	10 CFR 50.73(a)(2)(iv), System Actuation 10 CFR 50.73(a)(2)(x) 10 CFR 50.73(a)(2) 10 CFR 50.73(a)(2)(vii), Common Cause Inoperability 10 CFR 50.73(a)(2)(i)(A), Completion of TS Shutdown
3892022001R00 - NRC Website

text

U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555 Re: St. Lucie Unit 2 Docket No. 50-March 4, 2022 Reportable Event: 2022-001-00 Date of Event: January 6, 2022 L-2022-024 10 CFR 50.73 Reactor Shutdown Required by Technical Specifications due to a Misaligned Control Element Assembly The attached Licensee Event Report 2022-001 is being submitted pursuant to the requirements of 10 CFR 50.73 to provide notification of the subject event.

Respectfully,

()JO A-Daniel DeBoer Site Vice President St. Lucie Plant DD/res Attachment cc: St. Lucie NRC Senior Resident Inspector St. Lucie NRC Program Manager Florida Power& Light Company 6501 S. Ocean Drive, Jensen Beach, FL 34957 NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPR OVED B Y OM B : N O. 3150-0104 EXPI RES: 08/ 31/ 2023

( 08-2020) Estim ated S t. Luc i e Uni t 2 050003 89 1 of 3

4. Title Reac t o r S hut down Requi red by Tec hni cal Spec if i cati ons d ue t o a M i sal igned Co ntrol E l em ent A ss embl y

5. Event Date 6. LE R Numbe r 7. Report Date 8. Other Facilities Involved R evi s i on Facility Name Doc k et Number M onth D ay Year Year Seq uenti al N um ber Num ber M onth D ay Year n/ a 05000

Facility Name Doc k et Number 01 06 202 2 202 2 - 001 - 00 03 04 202 2 n/ a 05000

9. O pe ra ti ng Mode 10. Power Level 1 68%

1 1. THI S RE P O RT I S S UBMI TTE D P URS UANT TO THE RE Q UI RE ME NTS O F 1 0 CFR § : (Check all that apply)

10 CFR Part 20 20.2203(a)(2)(vi) 50.36(c)(2) 50.73(a)(2)(iv) (A ) 50.73(a)(2)(x)

20.2201(b) 20.2203(a)(3)(i) 50.46(a)( 3 )(ii) 5 0. 7 3 (a )(2 )(v)(A ) 10 CFR Part 73

20.2201(d) 20.2203(a)(3)(ii) 50.69(g) 5 0. 7 3 (a )(2 )(v)(B ) 73.71(a)(4)

20.2203(a)(1) 20.2203(a)(4) 5 0. 7 3 (a )(2 )(i)(A ) 50.73(a)(2)(v )(C) 73.71(a)(5)

20.2203(a)(2)(i) 10 CFR Part 21 5 0. 7 3 (a )(2 )(i)(B ) 5 0. 7 3 (a )(2 )(v)(D) 73.77(a)( 1)

20.2203(a)(2)(ii) 21.2(c) 5 0. 7 3 (a )(2 )(i)(C) 50.73(a)(2)(vii) 73.77(a)(2)(i)

20.2203(a)(2)(iii) 10 CFR Part 50 5 0. 7 3 (a )(2 )(ii)(A ) 5 0. 7 3 (a )(2 )(viii)(A ) 73.77(a)(2)(ii)

20.2203(a)(2)(iv) 5 0. 3 6 (c)(1 )(i)(A ) 50.73(a)( 2 )(ii)(B ) 5 0. 7 3 (a )(2 )(viii)(B )

20.2203(a)(2)(v) 5 0. 3 6 (c)(1 )(ii)(A ) 5 0. 7 3 (a )(2 )(iii) 5 0. 7 3 (a )(2 )(ix)(A )

O THE R ( Spec i fy her e, i n abs tr ac t or i n N R C 366A)

12. Licensee Contact for this LE R Li c ens ee C ontac t T el ephone N um ber ( Inc l ude ar ea code)

Ri c hard S c i scent e, Li c ensi ng E ngi neer (772) 4 67 -7156 1 3. Compl e te O ne Li ne for e a c h Compone nt Fa i l ure De s c ri be d i n thi s Re port C aus e System C om ponent M anuf ac tur er R epor tabl eT o IR IS C aus e System C om ponent M anuf ac tur er R epor tabl eT o IR IS

X AA MO W120 Y

1 4. S uppl e me nta l Re port Expected 15. Expected M onth D ay Year YES (If yes, complete 15. Expected Submission Date) NO S ubmis s ion Da te

Abstract (Limit t o 1560 s paces, i.e., approximat ely 15 s ingle -s pac ed ty pewritt en lines )

On J an u ar y 6, 2022 at 1937 EST with Unit 2 in Mode 1 at 68% power, the reactor was manually shutdown as required by Technical Specif ication Action Statement 3.1.3.1.e, due to Control Element Assembly ( CEA) #27 misaligned f rom its CEA Group and unable to be realigned with its group with in prescribed time limits.

Initial troubleshooting determined that the direct cause was a malf unction of the CEA #27 Control Element Drive Mechanism (CEDM) motor. The #27 CEDM motor was replaced while Un it 2 w as in Mode 5.

Reactor shutdowns ar e an al y z e d events in the Updated Final Saf ety Analysis Report. The shutdown was uncomplicated. Therefore, this event had no impact on the health and saf ety of the public.

Descr iption On January 6, 2022 at 1937 EST with Unit 2 in Mode 1 at 68% power, the reactor was manually shutdown as required by Technical Specif ication Action Statement 3.1.3.1.e, due to Control Element Assembly (CEA) #27 [AA:ROD] misaligned f rom its CEA Group and una ble to be realigned with its group with in p r e scr ib e d time limits.

On January 6, 2022 at 0824, CEA #27 slipped f rom 133 inches to 120 inches withdrawn while being exercised f or surveillance testing. The condition resulted in a position deviation of greater than 15 inches and entry into Techn i c al Specif ication Action Statement (TSAS) 3.1.3.1. e. Attempts to withdraw CEA #27 were not successf ul and Unit 2 was downpowered to 70% in accordance with T SAS 3.1.3.1.e. Subsequent attempts to r ealign t h e CEA while at 70% power and within time limitations of TSAS 3.1.3.1.e were unsuccessful, and Unit 2 was shutdown to Mode 3 t o e x it T SAS 3.1.3.1.e.

Cause of the Event

Initial troubleshooting determined that the direct cause was a malf unction of the CEA #27 Contr ol Element Drive Mechanism (CEDM) motor [AA:MO]. The #27 CEDM motor was replaced while Un it 2 w as in Mode 5.

Upon removal, the CEA #27 CEDM motor was inspected onsite to document initial f indings. This inspection identified a cylindrical metallic object f ound between the upper gripper s movable latch magnet and the top of the pull - down magnet. The CEDM motor was packaged and shipped to an o f f site facility f o r c o nf i r mat o r y inspection, disassembly and analysis.

Analysis of the Event

This licensee event report is being submitted in accordance with 10 CFR 50.73(a)(2)(i)(A) as The completion of any nuclear plant shutdown required by the plants Technical Specif ications. During this event, the reactor was operated with in th e limits o f TSAS 3.1.3.1.e; therefore, t his event had no signif icant saf ety consequence.

Saf ety Signif icance Reactor shutdowns ar e described in the UFSAR as anticipated operational occurrences.

There were no complications, and all saf ety related systems f unctioned as designed. There were no saf ety system actuations as a r esult of the event. Given the response of the plant and the plant design that can accommodate this anticipated operational oc currence, the health and saf ety of the public were not af f ected by this event.

Corrective Actions

Operability of CEA #27 was restored by the initial corrective action to replace the #27 CEDM motor.

If the additional f orensic evaluation described above identifies significant additional inf ormation, this LER will be supplemented.

Failed Components Identif ied

1) CEDM #27 motor

Description

CEDM mag n e tic jack asse mb ly

Part Number: E-13172-163- 0 01-1

Description

CEDM motor assembly

Part Number: SCEDM-163-202

Serial Number: N4720 S/N 158

Manuf acturer: Westinghouse

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