ML22062B023

NRR E-mail Capture - EPID-L-2022-LLR-0028, LaSalle Unit 1, Request for Additional Information (Rai), LaSalle Unit 1, Relief Request I4R-13 Relief from Code Examinations for 1B33-F060A and 1B33-F060B Repairs

ML22062B023
Person / Time
Site:	LaSalle
Issue date:	03/03/2022
From:	Bhalchandra Vaidya NRC/NRR/DORL/LPL3
To:	Taken J Exelon Generation Co
References
L-2022-LLR-0028
Download: ML22062B023 (3)

Text

From: Vaidya, Bhalchandra Sent: Thursday, March 3, 2022 10:59 AM To: Taken, Jason C:(Constellation Nuclear)

Cc: Cumblidge, Stephen; Mitchell, Matthew; Reichelt, Eric; Salgado, Nancy; Schaup, William; Wiebe, Joel

Subject:

EPID-L-2022-LLR-0028, LaSalle Unit 1, Request for Additional Information (RAI), LaSalle Unit 1, Relief Request I4R-13 Relief from Code Examinations for 1B33-F060A and 1B33-F060B Repairs

SUBJECT:

LASALLE UNITS 1 AND 2 -REQUEST FOR ADDITIONAL INFORMATION (RAI)

RE: Relief Request I4R-13 Relief from Code Examinations for 1B33-F060A and 1B33-F060B Repairs (EPID-L-2022-LLR-0028)

Jason, By letter to the U.S. Nuclear Regulatory Commission (NRC) dated March 2, 2022 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML22061A000),

Constellation Energy Generation, LLC (CEG, the licensee) submitted a Relief Request I4R-13 Relief associated with repair of the LSCS Unit 1 Reactor Recirculation flow control valves, 1B33-F060A and 1B33-F060B, which is currently in progress.

Specifically, I4R-13 requests authorization of alternative examination requirements for the repair of the valves in accordance with ASME Section XI, paragraph IWA-4000. Additionally, I4R-13 requests relief from the radiography examination requirements required by NB-2539 for the 1B33-F060A and 1B33-F060B.

The U.S. Nuclear Regulatory Commission (NRC) staff currently reviewing your submittal. The NRC staff has identified areas where additional information is needed to complete its review. The Request For Additional Information (RAI) is provided below.

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REQUEST FOR ADDITIONAL INFORMATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION FOR PROPOSED ALTERNATIVE NUMBER I4R-13 ALTERNATIVE EXAMINATION REQUIREMENTS FOR REPAIR OF REACTOR RECIRCULATION FLOW CONTROL VALVES CONSTELLATION ENERGY GENERATION, LLC LASALLE COUNTY STATION, UNIT 1 DOCKET NO. 50-373 By letter to the U.S. Nuclear Regulatory Commission (NRC) dated March 2, 2022, Constellation Energy Generation, LLC (the licensee) proposed an alternative to certain requirements of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME Code),

Section III and Section XI, related to the repair of degraded Reactor Recirculation Flow Control Valves at LaSalle County Station, Unit 1 (LaSalle Unit 1). The licensee submitted Relief

Request No. I4R-13, for the proposed alternative Enhanced Visual testing (EVT) examination requirements in lieu of the required Penetrant Testing (PT) for the repairs.

The NRC has determined that the following additional information is necessary to complete its review and make a regulatory decision.

1. The 2021 Relief Request I4R-12 for LaSalle Unit 2 (ADAMS Accession No. ML21085A874) discussed the unusual wear of similar valve bodies in Unit 2 and stated that it was attributed to an atypical low-power operating condition that occurred in 2015.

Relief Request 14R-13, for Lasalle Unit 1, described wear in the valve bodies but does not give any specific reason for the wear. Discuss whether the root cause of the wear for LaSalle Unit 1 is understood to be the same as for Unit 2, or whether a different cause of the wear is present for Unit 1.

2. In Relief Request 14R-13, the wear rate in the valves after the repairs is expected to be 0.00015 inches per operating cycle. Please provide details on this wear rate calculation and the uncertainties in the calculation.

3. In Relief Request 14R-13, the licensee stated that, notwithstanding the observed wear, Valve Bodies 1B33-F060A and 1B33-F060B remain above the minimum wall thickness.

It is stated that at this time 1B33-F060B does not require welding, however, in the event that the repair plans require welding, welding would be conducted in accordance with the ASME Code. Valve Body 1B33-F060A requires repair welding and machining.

In the Relief Request I4R-12 for Unit 2, it was stated that surface conditioning of the valve surfacing prior to welding reduced the total thickness to below the minimum required wall thickness. Please specify if surface conditioning for Unit 1 will be performed prior to welding on these valves, and what plans are in place if the wall thickness is reduced to below the minimum wall thickness.

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During the clarification telephone conference on March 3, 2022, you have committed to provide the responses to these RAIs by COB today, March 3, 2022.

Please contact me, if you have any questions.

Bhalchandra K. Vaidya US Nuclear Regulatory Commission Office of Nuclear Reactor Regulation Division of Operating Reactor Licensing LPL3 301-415-3308 Bhalchandra.vaidya@nrc.gov

Hearing Identifier: NRR_DRMA Email Number: 1543 Mail Envelope Properties (DM8PR09MB6181F98FFAF3A74CA1BF2EC28D049)

Subject:

EPID-L-2022-LLR-0028, LaSalle Unit 1, Request for Additional Information (RAI),

LaSalle Unit 1, Relief Request I4R-13 Relief from Code Examinations for 1B33-F060A and 1B33-F060B Repairs Sent Date: 3/3/2022 10:59:22 AM Received Date: 3/3/2022 10:59:00 AM From: Vaidya, Bhalchandra Created By: Bhalchandra.Vaidya@nrc.gov Recipients:

"Cumblidge, Stephen" <Stephen.Cumblidge@nrc.gov>

Tracking Status: None "Mitchell, Matthew" <Matthew.Mitchell@nrc.gov>

Tracking Status: None "Reichelt, Eric" <Eric.Reichelt@nrc.gov>

Tracking Status: None "Salgado, Nancy" <Nancy.Salgado@nrc.gov>

Tracking Status: None "Schaup, William" <William.Schaup@nrc.gov>

Tracking Status: None "Wiebe, Joel" <Joel.Wiebe@nrc.gov>

Tracking Status: None "Taken, Jason C:(Constellation Nuclear)" <Jason.Taken@constellation.com>

Tracking Status: None Post Office: DM8PR09MB6181.namprd09.prod.outlook.com Files Size Date & Time MESSAGE 4468 3/3/2022 10:59:00 AM Options Priority: Normal Return Notification: No Reply Requested: No Sensitivity: Normal Expiration Date: