ML17355A011

NRR E-mail Capture - Request for Additional Information Regarding Relief Request I5R-11, Revision 2

ML17355A011
Person / Time
Site:	Quad Cities
Issue date:	12/20/2017
From:	Kimberly Green Plant Licensing Branch III
To:	Nicely K Exelon Generation Co
References
Download: ML17355A011 (5)

Text

NRR-DMPSPEm Resource From: Green, Kimberly Sent: Wednesday, December 20, 2017 1:32 PM To: Nicely, Ken M.:(GenCo-Nuc)

Cc: Mathews, Mitchel A:(GenCo-Nuc); Steinman, Rebecca L:(GenCo-Nuc)

Subject:

Request for Additional Information Regarding Relief Request I5R-11, Revision 2 Attachments: Final RAI.docx

Dear Mr. Nicely:

By letter dated February 14, 2017, Exelon Generation Company, LLC (EGC) submitted a request for alternatives for Quad Cities Nuclear Power Station, Unit 2 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML17045A681). The proposed request seeks alternatives for the penetration N-11B repair, including the subsequent examination requirements, for the N-11B nozzle to be examined at least once each nine years starting in refueling outage Q2R27 (i.e., spring 2024) for the remaining life of the plant.

The U.S Nuclear Regulatory Commission (NRC) staff is reviewing your submittal and has identified an area where additional information is needed to complete its review. Attached, please find a request for additional information (RAI). The specific information requested is addressed in the attachment to this email. A draft RAI was transmitted to you by email dated December 19, 2017. You indicated that EGC does not need a clarification call regarding the request.

1

In order to support the requested approval date of February 14, 2018, the NRC requests a response to the RAI by January 12, 2018. The NRC staff considers that timely responses to RAIs help ensure sufficient time is available for staff review and contribute toward the NRC's goal of efficient and effective use of staff resources.

If circumstances result in the need to revise the requested response date, please contact me at (301) 415-1627.

Sincerely, Kimberly Green (301) 415-1627 kimberly.green@nrc.gov 2

Hearing Identifier: NRR_DMPS Email Number: 64 Mail Envelope Properties (Kimberly.Green@nrc.gov20171220133100)

Subject:

Request for Additional Information Regarding Relief Request I5R-11, Revision 2 Sent Date: 12/20/2017 1:31:32 PM Received Date: 12/20/2017 1:31:00 PM From: Green, Kimberly Created By: Kimberly.Green@nrc.gov Recipients:

"Mathews, Mitchel A:(GenCo-Nuc)" <Mitchel.Mathews@exeloncorp.com>

Tracking Status: None "Steinman, Rebecca L:(GenCo-Nuc)" <Rebecca.Steinman@exeloncorp.com>

Tracking Status: None "Nicely, Ken M.:(GenCo-Nuc)" <ken.nicely@exeloncorp.com>

Tracking Status: None Post Office:

Files Size Date & Time MESSAGE 1574 12/20/2017 1:31:00 PM Final RAI.docx 22569 Options Priority: Standard Return Notification: No Reply Requested: No Sensitivity: Normal Expiration Date:

Recipients Received:

REQUEST FOR ADDITIONAL INFORMATION EXELON GENERATION COMPANY, LLC QUAD CITIES NUCLEAR POWER STATION, UNIT 2 DOCKET NUMBER 50-265 CAC NUMBER MF9286; EPID L-2017-LLR-0004

Background:

Paragraph 50.55a(g)(4)(ii) of Title 10 of the Code of Federal Regulations (10 CFR) requires, in part, that licensees examinations and tests conducted during successive 120-month inspection intervals comply with the requirements of the latest edition and addenda of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME Code) incorporated by reference in 10 CFR 50.55a(a) 12 months before the start of the 120-month inspection interval (or the optional ASME Code Cases listed in NRC Regulatory Guide (RG) 1.147, when using ASME BPV Code,Section XI, or RG 1.192, when using the ASME OM Code, as incorporated by reference in paragraphs 50.55a(a)(3)(ii) and (iii)), subject to the conditions listed in 10 CFR 50.55a(b).

Based on this regulation, the NRC has generally limited the duration of alternatives to the ASME Code proposed under 10 CFR 50.55a(z) that involve inspection requirements to the licensees current 10-year inservice inspection (ISI) interval. The NRC staff has, on limited occasions, authorized alternatives that extend into the subsequent ISI interval: (1) when the request was made toward the end of the current interval and the NRC staff was certain that the code requirements affected by the request were the same in both intervals, or (2) when supported by a flaw analysis demonstrating the acceptability of operation into the next ISI interval. In case (2) the duration of the authorized alternative has generally been to the end of the period supported by the flaw evaluation. For continued use of the proposed alternative beyond the end date of the flaw analysis, a subsequent proposal has been submitted and evaluated by the NRC staff.

In the request dated February 14, 2017, Exelon Generation Company, LLC (EGC) requested authorization of three alternatives for the life of plant. In support of the previous revision of the alternative request, EGC performed a flaw evaluation, which concluded that the postulated circumferential and axial flaws are acceptable for at least 9 years of operation. This analysis was reviewed and approved by the NRC. During refueling outage Q2R23 (i.e., spring 2016),

EGC examined the J-groove weld flaw using a non-destructive examination (NDE) technique that showed there were no indications extending into the ferritic low-alloy reactor pressure vessel base metal. Therefore, EGC concluded that an additional 9-year period of operation, from the spring 2016 refueling outage until a required examination during the 2024 refueling outage would be performed, was supported. EGC requested authorization of one of the alternatives until the end of plant life based on performing a demonstrated NDE technique every 9 years to verify that the flaw is bounded by the assumptions of the flaw evaluation. However, the staff cannot authorize the requested alternative beyond 9 years based on the results of future NDE.

Request:

Please revise Relief Request I5R-11, Revision 2, to reflect a duration supported by the flaw evaluation (e.g., 9 years beyond the date when the NDE technique was performed in 2016) or provide justification to demonstrate that a longer interval can be technically supported without relying on future unknown NDE results.