ML24332A090
| ML24332A090 | |
| Person / Time | |
|---|---|
| Site: | Ginna  |
| Issue date: | 11/27/2024 |
| From: | Para W Constellation Energy Generation |
| To: | Office of Nuclear Reactor Regulation, Document Control Desk |
| References | |
| Download: ML24332A090 (1) | |
Text
200 Energy Way Kennett Square, PA 19348 www.constellation.com 10 CFR 50.55a November 27, 2024 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555-0001 R. E. Ginna Nuclear Power Plant Renewed Facility Operating License Nos. DPR-18 NRC Docket No. 50-244
Subject:
Alternative Request Associated with Inservice Testing of Loop B Letdown Relief Valve In accordance with 10 CFR 50.55a, Codes and standards, paragraph (z)(2), Constellation Energy Generation, LLC (CEG) requests NRC approval of a proposed Alternative Request associated with the Inservice Testing (IST) Program for the R. E. Ginna Nuclear Power Plant (Ginna). The IST Program for the sixth 10-year interval began on January 1, 2020, and adopted the 2012 Edition of the American Society of Mechanical Engineers (ASME) Code for Operation and Maintenance of Nuclear Power Plants (OM Code) with no Addenda. This request is associated with the testing of the Loop B Letdown Relief Valve, 203 (RV-203).
Replacement of RV-203 requires the plant to be shutdown therefore RV-203 is normally replaced with a pre-tested spare every 3 years to align with refueling outages and meet the ASME OM Code requirement in Mandatory Appendix I, Subsection I, I-1350(a) of 48-months. The currently installed relief valve was installed during Ginnas 2021 refueling outage and was scheduled for replacement during Ginnas 2024 refueling outage, however the spare valve failed pre-installation testing. Efforts to repair the spare valve or identify a suitable replacement were unsuccessful and the installed relief valve (Serial Number 50998) remained in service. RV-203 will exceed the Mandatory Appendix I, Subsection I, I-1350 48-month requirement on March 22, 2026 which is before the scheduled start of the Spring 2026 Ginna refueling outage (G1R46). Compliance with Mandatory Appendix I, Subsection I-1350(a) would cause a hardship or unusual difficulty without a compensating increase in the level of quality or safety due to the need to perform a mid-cycle shutdown in order to perform the required testing. Therefore, CEG is requesting a one-time extension for the test interval of RV-203 until no later than the end of G1R46.
CEG requests your approval of this request by November 30, 2025.
There are no regulatory commitments contained in this letter.
Alternative Request Associated with Inservice Testing of Loop B Letdown Relief Valve November 27, 2024 Page 2 If you have any questions, please contact Steven Bowers at 267-533-5101.
Respectfully, Wendi Para Sr. Manager - Licensing Constellation Energy Generation, LLC
Attachment:
Alternative Request VR Inservice Testing of Loop B Letdown Relief Valve cc:
USNRC Region I, Regional Administrator USNRC Senior Resident Inspector, Ginna Nuclear Power Plant USNRC Project Manager, Ginna Nuclear Power Plant
Alternative Request Associated with Inservice Testing of Loop B Letdown Relief Valve November 27, 2024 Page 3 bcc:
Sr. Vice President, MidAtlantic Operations w/attachment Senior Vice President, Engineering and Technical Services Vice President, Licensing and Regulated Site Vice President - Ginna Plant Manager - Ginna Director, Site Operations - Ginna Director, Site Engineering - Ginna Director, Site Maintenance - Ginna Manager, Regulatory Assurance - Ginna Director, Licensing - KSA (S. Mokkapati)
Sr. Manager, Licensing - KSA (W. Para)
Records Management - KSA Licensing - KSA (S. Bowers)
ATTACHMENT Alternative VR Inservice Testing of Loop B Letdown Relief Valve
10 CFR 50.55a Alternative: VR-04 Revision 0 Page 1 of 3 Request for Alternative VR-04 Inservice Testing of Loop B Letdown Relief Valve In Accordance with 10 CFR 50.55a(z)(2)
- 1. ASME Code Component(s) Affected Component ID Description Code Class Category 203 Loop B Letdown to Non-Regenerative Heat Exchanger Relief Valve to Pressurizer Relief Tank 2
C The Loop B Letdown relief valve provides overpressure protection for Class 2 Chemical Volume Control System (CVCS) letdown piping, the Residual Heat Removal (RHR) low head safety injection/shutdown cooling header, and the letdown line containment penetration.
- 2. Applicable Code Edition and Addenda American Society of Mechanical Engineers (ASME) Code for Operation and Maintenance of Nuclear Power Plants (OM Code) 2012 Edition with no Addenda.
3. Applicable Code Requirement
Mandatory Appendix I, Subparagraph I, I-1350(a) states, in part, a minimum of 20% of the valves from each valve group shall be tested within any 48-mo interval.
4. Reason for Request
Pursuant to 10 CFR 50.55a, Codes and Standards, paragraph (z)(2), an alternative to the requirement of ASME OM Code I-1350(a) is proposed. The basis of the request is that compliance with the specified requirements would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety.
RV-203 is a group of 1 (i.e., the only relief valve in the group). Replacement of RV-203 requires the plant to be shutdown therefore RV-203 is normally replaced with a pre-tested spare every 3 years to align with refueling outages and meet the ASME OM Code requirement in Mandatory Appendix I, Subparagraph I-1350(a) of 48-months. The currently installed relief valve, serial number 50998, had been installed during Ginnas 2021 refueling outage and was scheduled for replacement during Ginnas 2024 refueling outage, however the spare valve failed pre-installation testing. The spare valve had tested satisfactory when removed from service in 2021 and was returned to inventory without in-body repairs. After failing the pre-installation test in 2024, parts for repair were obtained but were deemed insufficient. The reinstallation of the valve without these parts would have presented undue risks for boric acid leaks. Further, the additional necessary parts for repairing the valve were not readily available and the associated delay would have been a significant impact to the duration of the refueling outage.
10 CFR 50.55a Alternative: VR-04 Revision 0 Page 2 of 3 With no replacement valve readily available, the station evaluated the currently installed relief valve to determine if it could be left in service. Based on the valves consistent and satisfactory test history, as provided in Section 5, the site left the currently installed relief valve, serial number 50998, in service.
This valve cannot be replaced on-line as RV-203 relieves to the Pressurizer Relief Tank (PRT). The Power Operated Relief Valves and Pressurizer Safety Valves also relieve to the PRT making full energy isolation not achievable.
Based on the pre-service test date of September 22, 2021 for the currently installed relief valve, and using Code Case OMN-20, Inservice Test Frequency, which permits a six-month grace period for test frequencies that are greater than or equal to two years, RV-203 will exceed the Mandatory Appendix I, Subparagraph I, I-1350 48-month requirement on March 22, 2026, which is before the scheduled start of the Spring 2026 Ginna refueling outage (G1R46). Compliance with Mandatory Appendix I, Subparagraph I-1350(a) would cause a hardship or unusual difficulty without a compensating increase in the level of quality or safety due to the need to perform a mid-cycle shutdown in order to perform the required testing.
5. Proposed Alternative and Basis for Use
The proposed alternative pursuant to 10 CFR 50.55a(z)(2) is for a one-time extension to the current test interval to allow replacement of RV-203 with a rebuilt and pre-tested spare valve during G1R46.
A review going back to 2009 of the currently installed valve, serial number 50998, shows that all As-Found testing was satisfactory.
Date Serial Number As Found Test Result 2018 50998 SAT 2015 50998 SAT 2009 50998 SAT
6. Duration of Proposed Alternative
This request, upon approval, will be applied until the end of G1R46. This provides an adequate window of opportunity to obtain parts, rebuild the spare relief valve, and install the spare during Ginnas scheduled 2026 refueling outage.
- 7. Precedent The NRC authorized H. B. Robinson Steam Electric Plant, Unit No. 2, for a one-time extension of the testing interval for a Code Class 3 Pressure Relief Valve due to a hardship resulting from the Units September Refueling Outage being rescheduled to November 2020.
H. B. Robinson Steam Electric Plant Unit No. 2 - Relief Request RA-19-0428 for One-Time Pressure Relief Valve Test Frequency Extension (EPID-L-2019-LLR-0019), dated August 19, 2020 (ML20199M275)
10 CFR 50.55a Alternative: VR-04 Revision 0 Page 3 of 3 The NRC authorized Watts Barr Nuclear Plant, Unit 1, for a one-time extension of the testing interval for three relief valves due to a hardship resulting from timing of the Units planned November 2021 refueling outage.
Watts Bar Nuclear Plant, Unit 1 - Authorization and Safety Evaluation for Alternative Request No. IST-RR-9 (EPID L-2021-LLR-0031), dated September 20, 2021 (ML21244A345)
- 8. References None