05000440/LER-2019-002, Loss of Safety Function Due to Low Pressure Core Spray Inoperability

Loss of Safety Function Due to Low Pressure Core Spray Inoperability

ML19199A150
Person / Time
Site:	Perry
Issue date:	07/18/2019
From:	Payne F FirstEnergy Nuclear Operating Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
L-19-153 LER 2019-002-00
Download: ML19199A150 (5)

LER-2019-002, Loss of Safety Function Due to Low Pressure Core Spray Inoperability

Event date:
Report date:
Reporting criterion:	10 CFR 50.73(a)(2)(v), Loss of Safety Function 10 CFR 50.73(a)(2)(ii)(A), Seriously Degraded 10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition 10 CFR 50.73(a)(2)(iii) 10 CFR 50.73(a)(2)(iv)(A), System Actuation 10 CFR 50.73(a)(2)(viii)(A) 10 CFR 50.73(a)(2)(viii)(B) 10 CFR 50.73(a)(2)(ix)(A) 10 CFR 50.73(a)(2)(x) 10 CFR 50.73(a)(2)(v)(A), Loss of Safety Function - Shutdown the Reactor 10 CFR 50.73(a)(2)(v)(B), Loss of Safety Function - Remove Residual Heat 10 CFR 50.73(a)(2)(i)(A), Completion of TS Shutdown
4402019002R00 - NRC Website

text

FENOC FirstEnergy Nuclear Operating Company Perry Nuclear Power Plant P.O. Box97 10 Center Road

Perry, Ohio 44081 Frank Payne 440-280-5382 Vice President July 18, 2019 L-19-153 10CFR50.73(a)(2)(v)(D)

ATTN:

Document Control Desk U. S. Nuclear Regulatory Commission Washington, DC 20555-0001

SUBJECT:

Perry Nuclear Power Plant Docket No. 50-440, License No. NPF-58 Licensee Event Report Submittal Enclosed is Licensee Event Report (LER) 2019-002, "LER 2019-002, Loss of Safety Function due to Low Pressure Core Spray Inoperability".

There are no regulatory commitments contained in this submittal.

If there are any questions or if additional information is required, please contact Mr. Glendon Burnham, Manager - Regulatory Compliance, at (440) 280-7538.

Sincerely, Frank R. Payne Vice President

Enclosure:

LER 2019-002 cc:

NRC Project Manager NRC Resident Inspector NRC Region III Regional Administrator

Enclosure L-19-153 LER 2019-002

NRC FORM 366 (04-2018)

U.S. NUCLEAR REGULATORY COMMISSION LICENSEE EVENT REPORT (LER)

(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.qov/readinQ-rm/doc-collections/nureas/staff/sr1022/r3/

APPROVED BY OMB:

NO. 3150-0104 EXPIRES:

3/31/2020

, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.

1. Facility Name Perry Nuclear Power Plant

2. Docket Number 05000-440

3. Page 1

OF

4. Title:

Loss of Safety Function Due to Low Pressure Core Spray Inoperability

5. Event Date

6. LER Number

7. Report Date

8. Other Facilities Involved Month Day Year Sequential rear I

Number l

Rev No.

Month Day Facility Name Docket Number 05000 05 24 2019 2019 002 00 07 18 2019 Facility Name Docket Number 05000

9. Operating Mode

11. This Report is Submitted Pursuant to the Requirements of 10 CFR §:

(Check all that apply)

20.2201 (b) 20.2201 (d) 20.2203(a)(1)

20:2203(a)(2)(i)

20.2203(a)(3)(i)

D 20.2203(a)(3)(ii)

20.2203(a)(4)

50.36(c)(1)(i)(A)

50.73(a)(2)(ii)(A)

50.73(a)(2)(ii)(B)

D 50.73(a)(2)(iii) 50.73(a)(2)(iv)(A)

50.73(a)(2)(viii)(A) 50.73(a)(2)(viii)(B)

50.73(a)(2)(ix)(A) 50.73(a)(2)(x)

10. Power Level

20.2203(a)(2)(ii) 50.73(a)(2)(v)(A)

D 73.71 (a)(4)

20.2203(a)(2)(iii)

50.36(c)(2) 50.73(a)(2)(v)(B) 73.71 (a)(5)

20.2203(a)(2)(iv)

50.46(a)(3)(ii) 50.73(a)(2)(v)(C)

73.77(a)(1) 100

20.2203(a)(2)(v)

Q 50.73(a)(2)(i)(A) 50.73(a)(2)(v)(D)

73.77(a)(2)(i)

D Other (Specify in Abstract below or in =

Energy Industry Identification System (EMS) codes are identified in the text as [XX].

INTRODUCTION

(

The inoperability and loss of safety function of Low Pressure Core Spray (LPCS) [BM] system occurred as a result of the inoperability of Emergency Service Water (ESW) [Bl] A based upon the receipt of unexpected alarms in the Control Room for Residual Heat Removal (RHR) [BO] A and Division 1

Diesel Generator (DG)

[EK] out of service, following the start of ESW A pump for pump packing adjustment.

Subsequent investigation discovered that the control power fuses for ESW A pump breaker closing power were not seated properly.

With LPCS being a single train safety system, this resulted in a loss of function, resulting in a 10 CFR 50.72 notification and a 10 CFR 50.73 report.

EVENT DESCRIPTION

On May 24, 2019 at 0730 hours0.00845 days <br />0.203 hours <br />0.00121 weeks <br />2.77765e-4 months <br /> and with the reactor in MODE 1 at 100 percent rated thermal power, unexpected alarms were received for RHR A and Division 1 DG but of service, following the start of ESW pump A for pump packing adjustment.

Control room panel indications were illuminated for ESW Pump A Breaker Out / Power Loss / Overload.

ESW A pump remained running during this time.

Upon investigation of the ESW A pump breaker EH1106, it was discovered that the closing control power fuses (AX) were not seated properly.

This resulted in inoperability of the ESW A system.

As a result of the ESW A inoperability, the LPCS system was declared inoperable along with the other supported systems in accordance with Technical Specifications.

LPCS is described as a single train safety system in site procedures.

As such, when LPCS has an unplanned inoperability, it is reportable to the NRC under 10 CFR 50.72(b)(3)(v)(D) and 10 CFR 50.73(a)(2)(v)(D) as a Loss of Safety Function.

Fuse block AX for breaker EH 1106 was re-seated by the initial responder and further investigation determined that the AX fuse block, when properly and fully seated, had no issue staying properly in place and with adequate tightness.

This demonstrated that the closing power fuse block was not loose and was not jarred out of the seated position during breaker operation.

ESW A pump was then stopped and restarted successfully.

ESW A was declared operable on May 24, 2019 at 1512 hours0.0175 days <br />0.42 hours <br />0.0025 weeks <br />5.75316e-4 months <br />.

On May 24, 2019 at 1309 hours0.0152 days <br />0.364 hours <br />0.00216 weeks <br />4.980745e-4 months <br />, Notification (EN 54085) was made under 10 CFR 50.72(b)(3)(v)(D).

This Licensee Event Report is being reported under 10 CFR 50.73(a)(2)(v)(D) as a loss of safety function.

CAUSE OF EVENT

The cause for ESW A inoperability is that the Non-Licensed Operators (NLO) did not recognize that the control power fuses (AX) for ESW A pump breaker closing power were not fully seated following installation, during recent breaker racking activities in accordance with procedure SOI-R22, Metal Clad Switchgear 5-15 Kilovolt (KV).

EVENT ANALYSIS

A Probabilistic Risk Assessment (PRA) evaluation was performed for the May 24, 2019 loss of safety function event.

A conservative analysis of this condition results in an increase in Core Damage Frequency (CDF) and Large Early Release Frequency (LERF) that is well below the acceptable thresholds discussed in Regulatory Guide 1.174.

The calculated increase in risk for this event is therefore considered to be very small.

CORRECTIVE ACTIONS

Fuse block AX, for breaker EH1106, was re-seated by the initial responder.

Further investigation determined that the AX fuse block, when properly and fully seated, had no issue relative to staying properly in place with adequate tightness.

A corrective action was written to change the 1) Perry Switchgear and 2) Electrical Operator Safety and Administration lesson plans to include a maintenance fundamental discussion of seating fuses and fuse blocks with physical or visual cues, including the importance of fully seated fuses within their receptors and identification of those fuse and fuse block receptors which may be loose and the need to identify the issue in the work management / corrective action processes.

A corrective action for an NLO topic for seating fuses and fuse blocks with physical or visual cues, including the importance of fully seated fuses, will be discussed during an NLO continuing training cycle.

PREVIOUS SIMILAR EVENTS

x None

COMMITMENTS

None(04-2018).'