ML21162A332
| ML21162A332 | |
| Person / Time | |
|---|---|
| Site: | Calvert Cliffs, Dresden, Peach Bottom, Nine Mile Point, Byron, Braidwood, Limerick, Ginna, Clinton, Quad Cities, FitzPatrick, LaSalle  |
| Issue date: | 06/11/2021 |
| From: | Tom Loomis Exelon Generation Co |
| To: | Rhoades D Exelon Generation Co, Exelon Nuclear |
| Purnell B | |
| References | |
| Download: ML21162A332 (5) | |
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Exelon BWR Fleet Relief Request Associated with RPV Instrument Nozzle Repairs June 15, 2021
Exelon Fleet BWR Relief Request for Nozzle Repair The purpose of this pre-emptive relief request is to provide a repair technique for the instrument nozzles in the Exelon BWR fleet for the duration of the operating cycle in which the indication is identified.
This pre-emptive relief request would mimic the two previously approved half-nozzle repairs for a 2-inch instrument line nozzle at Limerick Generating Station, Unit 2 and Peach Bottom Atomic Power Station, Unit 2.
Three previous NRC Safety Evaluation Reports (SERs) for a nozzle repair:
Quad Cities Nuclear Power Station, Unit 2 dated January 30, 2013 (ML13016A454)
Limerick Generating Station, Unit 2 dated March 5, 2019 (ML19009A002)
Peach Bottom Atomic Power Station, Unit 2 dated April 23, 2021 (ML21110A680) 2
Exelon Fleet BWR Relief Request for Nozzle Repair The previous relief requests and the proposed relief request will address the following elements of the repair evolution:
Examination of the j-groove welds and the RPV low alloy steel interface.
Technical details of the repair with referenced ASME Code Cases.
One-cycle flaw analytical evaluation with referenced ASME Code Cases.
Planned steps of the repair.
Commitments for the final one-cycle flaw analytical evaluation, evaluation of repair, and corrosion evaluation.
A similar pre-emptive repair relief request was obtained for Byron Station, Units 1 and 2, and Braidwood Station, Units 1 and 2 concerning alternative requirements for the repair of reactor Vessel Head Penetrations (VHPs) and J-groove Welds (ML16007A185, dated January 21, 2016).
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Exelon Fleet BWR Relief Request for Nozzle Repair This relief request does not support a bounding analysis / evaluations for the fleet.
Plant specific analyses will be submitted for each plant as was done for the Limerick and Peach Bottom Relief Request.
The flaw cannot be removed therefore a relief request would be needed and submitted in accordance with 50.55a(z)(2).
This relief request does not change the bases used in approved relief requests from Quad Cities Unit 2, Limerick Unit 2, and Peach Bottom Unit 2.
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Exelon Fleet BWR Relief Request for Nozzle Repair QUESTIONS?
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