ML22206A035
| ML22206A035 | |
| Person / Time | |
|---|---|
| Site: | Quad Cities  |
| Issue date: | 07/13/2022 |
| From: | Robert Kuntz NRC/NRR/DORL/LPL3 |
| To: | Steinman R Exelon Generation Co |
| References | |
| L-2022-LLR-0036 | |
| Download: ML22206A035 (4) | |
Text
From:
Kuntz, Robert Sent:
Wednesday, July 13, 2022 7:19 AM To:
Steinman, Rebecca L:(Constellation Nuclear)
Subject:
DRAFT RAI RE: Quad Cities Alternative related to SBLC nozzle inspection (EPID L-2022-LLR-0036)
By letter dated March 25, 2022 Constellation Energy Generation, LLC, (Constellation) submitted an alternative for inspection of standby liquid control nozzle inner radius at Quad Cities Nuclear Power Station, Units 1 and 2. The Nuclear Regulatory Commission (NRC) staff has determined that additional information is required to complete its review. The NRC staffs DRAFT request for additional information (RAI) is included. If Constellation requires clarification of the included DRAFT RAI contact me to set up a discussion with the NRC staff. If no clarification is required then this DRAFT RAI will be considered a formal RAI and a 30 day response from the date of this e-mail would be expected.
Robert Kuntz Senior Project Manager NRC/NRR/DORL/LPL3 (301) 415-3733 DRAFT REQUEST FOR ADDITIONAL INFORMATION REQUEST FOR ALTERNATIVE REGARDING AMERICAN SOCIETY OFMECHANICAL ENGINEERS, BOILER AND PRESSURE VESSEL CODE, SECTION XI EXAMINATION REQUIREMENTS FOR CLASS 1 NOZZLE INNER RADII DOCKET NOS. 50-254, AND 50-265 QUAD CITIES NUCLEAR POWER STATION, UNITS 1 AND 2 EPID NO. L-2022-LLR-0036 By letter dated March 25, 2022 (Agencywide Documents Access and Management System (ADAMS) ML22084A597), Constellation Energy Generation, LLC (the licensee) requested U.S.
Nuclear Regulatory Commission (NRC) approval of alternative I6R-01 pursuant to Title 10 of the Code of Federal Regulations (10 CFR) 50.55a(z)(2) to the requirements of American Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME Code) at Quad Cities Nuclear Power Station, Units 1 and 2 (Quad Cities 1 and 2). The proposed alternative would allow the licensee to forego American Society of Mechanical Engineers (ASME) Code, Section XI-required examination of the standby liquid control (SBLC) nozzle inner radius (IR) for the sixth inservice inspection interval (ISI) of the subject units.
Specifically, pursuant to Title 10 of the Code of Federal Regulations (10 CFR), Part 50, Paragraph 50.55a(z)(2), the licensee proposed to perform a VT-2 visual examination and monitor the technical specification surveillance requirement 3.4.4.1 for reactor coolant leakage instead of the required ultrasonic examination. 10 CFR 50.55a(z)(2) requires the licensee to demonstrate that conforming to the examination requirement would result in a hardship or
unusual difficulty without a compensating increase in the level of quality and safety. The NRC staff (the staff) requires additional information (RAI) to complete its review of the alternative request.
RAI 1
Issue: The alternative request did not specify the relevant materials of the SBLC nozzle and associated nozzle-to-vessel weld pictured in Figures I6R-01.1 of the submittal. This information is relevant to the request because it allows the staff to assess potential degradation mechanisms.
Request: Describe the materials of construction for the nozzle and weld at Quad Cities 1 and 2.
RAI 2
Issue: The alternative request did not address the operating experience and examination history of the nozzle-to-vessel weld of the SBLC nozzles of the subject units. This information is relevant to the request because it allows the staff to understand the overall performance of the SBLC nozzles.
Request: Describe the operating history and examination history of the nozzle-to-vessel weld of the SBLC nozzles, including a description of the ultrasonic examination coverage obtained, at Quad Cities 1 and 2.
RAI 3
Issue: The alternative request described partial examination history of the SBLC nozzle inner radius of the subject units, including the NRC-approved alternative for the fifth ISI interval.
However, the alternative request does not describe the examination history for the first through the fourth ISI intervals. This information is relevant to the request because it allows the staff to understand the full examination history of the SBLC nozzle inner radius.
Request: Describe the full examination history of the SBLC nozzle inner radius locations at Quad Cities 1 and 2.
RAI 4
Issue: The alternative request stated that performing an ultrasonic examination of the SBLC nozzle inner radius location would constitute a hardship or unusual difficulty without a compensating increase in quality or safety. However, the 2017 Edition of ASME Code,Section XI (the applicable code edition for the sixth ISI interval of the subject units) allows a VT-1 visual examination in lieu of an ultrasonic examination, provided the nozzle meets certain geometric conditions and provided the licensee meets the conditions specified in 10 CFR 50.55a(b)(2)(xxi)(B). The alternative request did not address the potential for performing the VT-1 examination. This information is relevant to the request because the licensee should analyze the entirety of the Section XI requirement as part of requesting an alternative.
Request: Describe the feasibility of performing the VT-1 examination for the SBLC nozzle inner radius specified in IWB-2500(g) in Section XI of the ASME Code, 2017 Edition, including all the relevant provisos in IWB-2500 and 10 CFR 50.55a(b)(2)(xxi)(B).
Hearing Identifier:
NRR_DRMA Email Number:
1723 Mail Envelope Properties (SA9PR09MB46406F888A607D180DA13D9299899)
Subject:
DRAFT RAI RE: Quad Cities Alternative related to SBLC nozzle inspection (EPID L-2022-LLR-0036)
Sent Date:
7/13/2022 7:19:25 AM Received Date:
7/13/2022 7:19:00 AM From:
Kuntz, Robert Created By:
Robert.Kuntz@nrc.gov Recipients:
"Steinman, Rebecca L:(Constellation Nuclear)" <Rebecca.Steinman@constellation.com>
Tracking Status: None Post Office:
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