05000387/LER-2022-001, Main Steam Isolation Valve Leakage

Main Steam Isolation Valve Leakage

ML22152A249
Person / Time
Site:	Susquehanna
Issue date:	06/01/2022
From:	Cimorelli K Susquehanna
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
LER 2022-001-00
Download: ML22152A249 (3)

LER-2022-001, Main Steam Isolation Valve Leakage

Event date:
Report date:
Reporting criterion:	10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications
3872022001R00 - NRC Website

text

Kevin Cimorelli Susquehanna Nuclear, LLC Site Vice President 769 Salem Boulevard Berwick, PA 18603 TALEN~.

Tel. 570.542.3795 Fax 570.542.1504 Kevin.Cimorelli@TalenEnergy.com ENERGY

June 1, 2022

Attn: Document Control Desk 10 CPR 50.73 U.S. Nuclear Regulatory Commission Washington, DC 20555-0001

SUSQUEHANNA STEAM ELECTRIC STATION LICENSEE EVENT REPORT 50-387/2022-001-00 UNIT 1 LICENSE NO. NPF-14 PLA-8002 Docket No. 50-387

Attached is Licensee Event Report (LER) 50-387/2022-001-00. The LER reports an event involving inoperability of a Main Steam Line Isolation Valve (MSIV) that was determined to be rep01iable in accordance with 10 CPR 50.73(a)(2)(i)(B) as a condition prohibited by Technical Specifications.

There were no actual consequences to the health and safety of the public as a result of this event.

This letter contains no new or revised regulatory commitments.

K. Cimorelli

Attachment: LER 50-387/2022-001-00

Copy: NRC Region I Mr. C. Highley, NRC Senior Resident Inspector Ms. A. Klett, NRC Project Manager Mr. M. Shields, PA DEP/BRP

Abstract

On April 02, 2022, during Local Leak Rate Testing (LLRT) conducted during the Unit 1 refueling outage, as-found leakage through the inboard Main Steam Isolation Valve (MSIV) (HV141 F022B) was 107,133 standard cubic centimeters per minute (seem) which exceeded the Technical Specification (TS) 3.6.1.3 limit of 100 standard cubic feet per hour (47,194 seem) for individual valve leakage.

Based on preliminary information, there is evidence that the condition existed during the last operating cycle for longer than allowed by TS 3.6.1.3. The condition is being reported in accordance with 1 O CFR 50.73(a)(2)(i)(B) as a condition prohibited by Technical Specifications.

The cause of the event is under investigation and will be provided in a supplement to this report. Repairs to the valve resulted in an acceptable as-left LLRT value. Additional corrective actions, as applicable, will be reported in the supplement. There were no actual consequences to the health and safety of the public as a result of this event.

U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY 0MB: NO. 3160-0104 EXPIRES: 08/31/2023 YEAR SEQUENTIAL NUMBER REV NO.

Susquehanna Steam Electric Station, 05000-387 Unit 1 2022 - 001 00

NARRATIVE

CONDITIONS PRIOR TO EVENT

Unit 1 - Mode 5, approximately O percent Rated Thermal Power (RTP)

Unit 2 - Mode 1, approximately 100 percent RTP

EVENT DESCRIPTION

On April 02, 2022, during Local Leak Rate Testing (LLRT) conducted during the Unit 1 refueling outage, as-found leakage through the inboard Main Steam Isolation Valve (MSIV) (HV141F022B) [EIIS System/Component Code: SB/ISV] was 107,133 standard cubic centimeters per minute (seem) which exceeded the Technical Specification (TS) 3.6.1.3 limit of 100 standard cubic feet per hour (47,194 seem) for individual valve leakage.

HV141 F022B was repaired resulting in an as-left individual valve LLRT value of 39,750 seem.

Based on preliminary information, there is evidence that the condition existed during the last operating cycle for longer than allowed by TS 3.6.1.3. The condition is being reported in accordance with 10 CFR 50.73(a)(2)(i)(B) as a condition prohibited by Technical Specifications.

CAUSE OF EVENT

The cause of the event is under investigation and will be provided in a supplement to this LER.

ANALYSIS/SAFETY SIGNIFICANCE

Analysis/Safety significance will be provided in a supplement to this LER.

CORRECTIVE ACTIONS

HV141 F022B was repaired resulting in a leak rate within TS 3.6.1.3 allowable value. Any additional corrective actions will be provided in a supplement to this LER.

COMPONENT FAILURE INFORMATION

Component Identification - HV141 F022B Component Name - Unit 1 Main Steam Line 'B' Inboard Isolation Valve Valve Manufacturer - Atwood & Morrill Co.

Valve Type - Wye Globe Valve Size - 26" Actuator Manufacturer - S&P Actuator Type - Tandem Cylinder

PREVIOUS OCCURRENCES

Previous occurrences, if any, will be provided in a supplement to this LER.