ML21258A101
| ML21258A101 | |
| Person / Time | |
|---|---|
| Site: | Saint Lucie  |
| Issue date: | 09/15/2021 |
| From: | Michael Mahoney NRC/NRR/DORL/LPL2-2 |
| To: | Godes W Florida Power & Light Co |
| References | |
| L-2021-LLR-0065 | |
| Download: ML21258A101 (5) | |
Text
From: Mahoney, Michael Sent: Wednesday, September 15, 2021 8:44 AM To: Godes, Wyatt Cc: Falkiewicz, Timothy; Jarrett.Mack@fpl.com
Subject:
St. Lucie Nuclear Plant, Unit 2 - Verbal Authorization of Relief Request 19, FP&L letter L-2021-184 (EPID L-2021-LLR-0065)
Attachments: Verbal Authorization Script - St Lucie U2 ASME Code Case 729 RCPHP 85 (L-2021-LLR-0065).docx Mr. Godes, In accordance with NRR Office Instruction LIC-102, Relief Request Reviews, the NRR staff provided verbal authorization on September 14, 2021 for St. Lucie Nuclear Plant, Unit 2, for the alternative relief request 19 in FP&L, as described in your letter L-2021-184 to the NRC dated September 13, 2021 (Agencywide Documents Access and Management System (ADAMS)
Accession No. ML21256A094).
The script read this afternoon that provides verbal authorization is attached. The NRC staff intends to follow-up this verbal authorization with a written safety evaluation within 150 days.
A copy of this email and attached verbal authorization will become publicly available in ADAMS, and I will provide the accession number to you.
Please let me know if you have any questions.
The following NRC and FP&L personnel participated in the call:
NRC David Wrona - Chief, Plant Licensing Branch II-2 (LPL2-2), Division of Operating Reactor Licensing (DORL), Office of Nuclear Reactor Regulation (NRR)
Matthew Mitchell - Chief, Piping and Head Penetrations Branch (NPHP), Division of New and Renewed Licenses (DNRL), NRR Michael Dudek - Acting Deputy Director (NRR/DORL)
Jay Collins - Senior Materials Engineer (NRR/DNRL/NPHP)
Mike Mahoney - Project Manager (NRR/DORL/LPL2-2)
Alexander Butcavage - Reactor Inspector (Region II)
Dan Orr - Senior Resident Inspector, St. Lucie Luke Haeg - Project Manager (NRR/DORL/LPL2-2)
Florida Power & Light Wyatt Godes - Licensing Manager Kathy Paez - Licensing Analyst Tim Falkiewicz - Licensing Engineer Paul Rasmus - Engineering Site Director Chris Martin - Radiation Protection/Chemistry Manager Boyd Beltz - Safety Assurance and Learning Site Director Harry Anderson - Performance Improvement Analyst Cheryl Eddy - Engineering Programs Manager Steve Catron - Fleet Licensing Manager Jarret Mack - Fleet Licensing
Don Church - Fleet Programs Manager Scott Boggs - Materials Engineer Donna Slivon - Engineering Analyst Mike Mahoney Project Manager, LPL2-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Desk: (301)-415-3867 Mobile: (301)-250-0450 Email: Michael.Mahoney@nrc.gov
Hearing Identifier: NRR_DRMA Email Number: 1348 Mail Envelope Properties (BLAPR09MB6017BCE894846418DEAEB654E5DB9)
Subject:
St. Lucie Nuclear Plant, Unit 2 - Verbal Authorization of Relief Request 19, FP&L letter L-2021-184 (EPID L-2021-LLR-0065)
Sent Date: 9/15/2021 8:44:04 AM Received Date: 9/15/2021 8:44:05 AM From: Mahoney, Michael Created By: Michael.Mahoney@nrc.gov Recipients:
"Falkiewicz, Timothy" <Timothy.Falkiewicz@fpl.com>
Tracking Status: None "Jarrett.Mack@fpl.com" <Jarrett.Mack@fpl.com>
Tracking Status: None "Godes, Wyatt" <Wyatt.Godes@fpl.com>
Tracking Status: None Post Office: BLAPR09MB6017.namprd09.prod.outlook.com Files Size Date & Time MESSAGE 2250 9/15/2021 8:44:05 AM Verbal Authorization Script - St Lucie U2 ASME Code Case 729 RCPHP 85 (L-2021-LLR-0065).docx 36000 Options Priority: Normal Return Notification: No Reply Requested: No Sensitivity: Normal Expiration Date:
VERBAL AUTHORIZATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION FOR RELIEF REQUEST NUMBER 19 REQUEST FOR AN ALTERNATE TO ASME CODE CASE N-729-6 FOR REPLACEMENT REACTOR VESSEL CLOSURE HEAD PENETRATION NOZZLE 85 FLORIDA POWER & LIGHT COMPANY ST. LUCIE NUCLEAR PLANT, UNIT NO. 2 DOCKET NO. 50-389 Technical Evaluation read by Matthew Mitchell, Chief of the Piping and Head Penetrations Branch, Office of Nuclear Reactor Regulation By letter L-2021-184, dated September 13, 2021, (Agencywide Documents Access and Management System (ADAMS) Accession No. ML21256A094), Florida Power and Light Company (the licensee, FPL) requested relief from Paragraphs -3142.2 and -3200 of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME Code)
Case N-729-6, Alternative Examination Requirements for PWR Reactor Vessel Upper Heads With Nozzles Having Pressure-Retaining Partial-Penetration Welds,Section XI, Division 1, as required by Title 10 of the Code of Federal Regulations (10 CFR), Part 50, Section 50.55a(g)(6)(ii)(D), related to supplemental examinations of reactor vessel closure head (RVCH) penetration number 85 at the St. Lucie Nuclear Plant, Unit 2 (St. Lucie, Unit 2). The licensee submitted Relief Request Number 19, for the proposed alternative, during the current fall 2021 refueling outage.
The licensee requested authorization for this alternative in accordance with the requirements of 10 CFR 50.55a(z)(2), on the basis that performing the supplemental examinations represents a hardship or unusual difficulty without a compensating increase in the level of quality and safety.
In performance of the current refueling outage bare metal visual examination (VE) of the RVCH, the licensee found a relevant condition on the head surface near RVCH penetration number 85.
After light cleaning and evaluation, the licensee took several actions to identify the source of the leakage and confirm it was not active pressure boundary leakage by isotopic analysis.
However, the licensee was not able to conclusively identify the source of the leakage.
Therefore, the licensee considered the indication on the head surface to be a relevant condition of possible nozzle leakage in accordance with Paragraph -3142.1 of ASME Code Case N-729-
- 6. Under these provisions, the licensee is required to perform either a repair/replacement activity or supplemental volumetric examinations in accordance with Paragraph -3200(b) of ASME Code Case N-729-6. Instead of the supplemental volumetric examinations, the licensee stated that it would clean the remaining area of the RVCH surface and verify the structural integrity of the RVCH. During the upcoming cycle of operation, the licensee stated that it would monitor for leakage in a manner which will continue to ensure the structural integrity of the RVCH. Finally, at the end of operating cycle 26, the licensee would perform an additional bare metal VE of the RVCH near penetration 85 to ensure no leakage is occurring.
The U. S. Nuclear Regulatory Commission (NRC) staff reviewed the licensees identified hardship and found the licensees estimation of radiological dose to perform the supplemental volumetric examinations during this outage was consistent with estimates at other facilities. The NRC staff finds that the radiological dose estimate of 7.5 person-REM for this work is a hardship on the licensee consistent with 10 CFR 50.55a(z)(2).
The NRC notes that the nozzle and weld material (alloy 690/52/152) of the RVCH at St. Lucie, Unit 2 has demonstrated no cracking in service in pressurized water reactor environments,
which supports the conclusion that it is unlikely that cracking is currently present. Further, even if minor leakage of a RVCH penetration was currently occurring, the known resistance of alloy 690/52/152 to crack-growth provides additional assurance that any cracking currently present would be unlikely to increase to the point of challenging the structural integrity of the RVCH over one additional operating cycle. Finally, the licensees identified leakage monitoring actions enable detection of the onset of, or increase in, leakage through a RVCH penetration prior to it presenting a challenge to structural integrity of the RVCH. Hence, the NRC finds that the licensees proposed alternative provides reasonable assurance of the structural integrity of the RVCH for the next operating cycle at St. Lucie, Unit 2 without requiring the licensee to perform supplemental volumetric examinations during the current refueling outage.
Therefore, the NRC staff finds, given the actions of the licensees proposed alternative, under Relief Request Number 19, there would be limited value in quality and safety in requiring additional supplemental volumetric examinations to verify no indications of cracking in these materials during the current refueling outage. Given the hardship, the NRC staff finds that (1) there is reasonable assurance that the licensees proposed alternative has a minimal impact on quality and safety; and (2) the licensees hardship justification is acceptable.
NRC Staff Conclusion read by Dave Wrona, Branch Chief, Plant Licensing Branch II, Office of Nuclear Reactor Regulation As Chief of Plant Licensing Branch II, I concur with the Piping and Head Penetration Branch's evaluation.
The NRC staff has determined that complying with the specified requirements described in the licensees Relief Request Number 19 would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety. Further, the licensees proposed alternative provides reasonable assurance of structural integrity of the RVCH and penetration nozzle number 85. Accordingly, the NRC staff concludes that the licensee has adequately addressed all of the regulatory requirements set forth in 10 CFR 50.55a(z)(2).
Therefore, as of September 14, 2021, the NRC authorizes the use of Relief Request Number 19 until the end of operating cycle 26 at St. Lucie, Unit 2, scheduled for Spring 2023.
All other requirements of ASME Code and 10 CFR 50.55a(g)(6)(ii)(D) for which relief was not specifically requested and authorized by the NRC staff remain applicable, including the third-party review by the Authorized Nuclear lnservice Inspector.
This verbal authorization does not preclude the NRC staff from asking additional questions and clarifications regarding Relief Request Number 19 while preparing the subsequent written safety evaluation.