L-2023-036, Notification of Deviation from Pressurized Water Owners Group (PWROG) Report WCAP-17451-P, Revision 1, Reactor Internals Guide Tube Wear - Westinghouse Domestic Fleet Operational Projections
| ML23055A292 | |
| Person / Time | |
|---|---|
| Site: | Point Beach  |
| Issue date: | 02/24/2023 |
| From: | Strand D Point Beach |
| To: | Office of Nuclear Reactor Regulation, Document Control Desk |
| References | |
| L-2023-036, WCAP-17451-P, Rev 1 | |
| Download: ML23055A292 (1) | |
Text
NEXTeraM February 24, 2023 ENERGY. L-2023-036
~
U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington DC 20555-0001 RE: Point Beach Nuclear Plant, Unit 2 Docket No. 50-301 Renewed Facility Operating Licenses DPR-27 Notification of Deviation from Pressurized Water Owners Group (PWROG) Report WCAP-17451-P, Revision 1, Reactor Internals Guide Tube Wear - Westinghouse Domestic Fleet Operational Projections
References:
- 1. Pressurized Water Owners Group (PWROG) Report WCAP-17451-P, Reactor Internals Guide Tube Wear - Westinghouse Domestic Fleet Operational Projections, Revision 1, October 2013
- 2. Nuclear Energy Institute (NEI) 03-08 Guideline for the Management of Materials Issues, Revision 4, October 2020 NextEra Energy Point Beach, LLC (NextEra) hereby provides notification of a change to the Control Rod Guide Tube (CRGT) guide card examination frequency for Point Beach Nuclear Plant Unit 2 (Point Beach).
The change represents a deviation from PWR Owners Group report WCAP-17451-P (Reference 1), which establishes the CRGT Guide Card Wear Measurement (GCWM) examination requirements as a "Needed" work product element for licensee reactor internals aging management programs. Nuclear Energy Institute (NEI) 03-08 (Reference 2), which provides requirements for "Needed" (versus mandatory) work product elements, allows deviations with the appropriate justification and documentation.
On February 8, 2023, NextEra approved an extension of the CRGT guide card examination frequency from 1O Effective Full Power Years (EFPY) to 20 EFPY in order to align with the latest industry approved CRGT guide card evaluation methodology (WCAP-17451-P, Revision 2). In NextEra letter ENG/JW-FPE-23-001, dated February 23, 2023, NextEra notified the PWROG of the intended deviation from the examination
- requirements of WCAP-17451-P, Revision 2, for Point Beach Unit 2.
The attachment to this letter provides NextEra report, "Point Beach Unit 2 Guide Card Wear Measurements Technical Justification Deviation from Examination Schedule in PWROG WCAP-17451-P, Revision 1". In accordance with NEI 03-08, Revision 4, this notification is being provided for information only and no action is being requested from the NRC staff.
NextEra Energy Point Beach, LLC 6610 Nuclear Road, Two Rivers, WI 54241
Point Beach Nuclear Plant, Unit 2 L-2023-036 Docket No. 50-301 Page 2 of 2 If you have any questions regarding th is submittal, please contact Mr. Kenneth Mack, Licensing Manager at (561) 904-3635.
This letter contains no new regulatory commitments.
Sincerely, D, ~ -:S t.7 Dianne Strand General Manager Regulatory Affairs Attachment - Point Beach Unit 2 Guide Card Wear Measurements Technical Justification Deviation from Examination Schedule in PWROG WCAP-17451-P Revision 1 cc: USNRC Regional Administrator, Region Ill Project Manager, USNRC, Point Beach Nuclear Plant Resident Inspector, USNRC, Point Beach Nuclear Plant Public Service Commission of Wisconsin
Point Beach Nuclear Plant, Unit 2 Docket No. 50-301 ATTACHMENT Point Beach Unit 2 Notification of Deviation from Pressurized Water Reactor Owners Group (PWROG) Report WCAP-17 451 -P, Revision 1, "Reactor Internals Guide Tube Wear - Westinghouse Domestic Fleet Operational Projections 4 pages follow
Point Beach Unit 2 Guide Card Wear Measurements Technical Justification Deviation from Examination Schedule in PWROG WCAP-17451-P Revision 1 Reason for Evaluation:
Point Beach Unit 2 has elected to defer the re-inspection of the Control Rod Guide Tube
. (CRGT) guide cards from the spring 2023 refueling outage (P2 R39) to the fall 2033 outage (P2 R46) or prior to 20 Effective Full Power Years (EFPY) from the last inspection. The CRGT guide cards were last inspected during the spring 2014 refueling outage (P2 R33) . This evaluation provides a technical justification for deviation from the NEI 03-08 "Needed" requirement specified in WCAP-17451-P, Revision 1 [Ref. 1]. A similar deviation was implemented for Point Beach Unit 1. [Ref. 9]
The CRGT guide card wear measurements (GCWM) require re-inspection no later than 10 calendar years after the baseline inspections per WCAP-17451-P, Revision 1, "unless adequate justification allows additional time," [Ref. 1]. The CRGT GCWM and CRGT guide card inspections are used interchangeably herein. The worst worn guide tube is at core location KO?,
and it was limited to 14.5 EFPY from the spring 2014 refuel outage per WCAP-18494-P, Revision 0
[Ref. 7].
In lieu of the 10-year maximum re-inspection limit, this deviation defers the Point Beach Unit 2 CRGT guide card re-inspection to a maximum of 20 EFPY after the baseline inspections per
- WCAP-17451-P, Revision 2 [Ref. 2], which is the latest industry approved revision of the CRGT guide card evaluation guidance. The industry approved 20 EFPY re-inspection frequency in Rev. 2 ofWCAP-17451-P, and it is referenced in MRP-227 Rev. 2, which is currently being reviewed by the NRC. The baseline CRGt guide card inspection data was evaluated for PBN Unit 2 using WCAP-18494-P Revision 0, and it supports a re-inspection interval of 20 EFPY from the spring 2014 refuel outage for all the CRGTs including the limiting CRGT at KO? [Ref. 7].
This is a change from the NEI 03-08 "Needed" requirement to use WCAP-17451-P Revision 1, which is referenced in WCAP-17096-NP-A Revision 2 [Ref. 4]. WCAP-17096-NP-A Revision 2 contains acceptable evaluation methodologies for reactor vessel internals for implementing MRP-227 Rev. 1-A, including the CRGT guide cards. The NRC acceptance ofWCAP-17096-NP Revision 3 [Ref. 5], which references use of WCAP-17451-P Revision 2 for the CRGT guide cards, is currently delayed due to ongoing issue resolution with other acceptance criteria methodologies within WCAP-17096-NP Revision 3.
Per NEI 03-08 [Ref. 6], a "Needed" work product is "to be implemented wherever possible, but alternative approaches are acceptable". When a utility determines that a "Needed" work product will not be fully implemented or will not be implemented in a manner consistent with their intent, or when a work product will not be implemented within the timeframe specified, a technical justification for the deviation shall be developed. This evaluation justifies deferring the Point Beach Unit 2 CRGT guide card inspections.
Expected Duration for which Justification/Deviation applies:
This deviation will apply until 2033 or when 20 EFPY is reached from the spring 2014 refuel outage for Point Beach Unit 2. It is anticipated the industry guidance, WCAP~17096-NP Revision 3, will be approved in the subsequent 1-2 years, which includes endorsement of WCAP-17451-P Revision 2. Once WCAP-17096-NP Rev. 3 is approved by the NRG, the 20 EFPY Deviation would be in accordance with the latest guidance.
Detailed Evaluation:
In support of license renewal activities, there are nine Primary Components that must be inspected for a Westinghouse Pressurized Water Reactor (PWR) in accordance with MRP-227 Revision 1-A industry guidance [Ref. 3]. The CRGT guide cards are considered one Primary component in MRP-227 Rev. 1-A. The CRGTs are part of the upper internals and provide guidance of the Rod Cluster Control Assemblies (RCCAs) above the core fuel assemblies. Each CRGT houses one RCGA that is made up of long, slender rodlets attached to a driv.e rod by a coupling fixture called a spider. The drive rod steps the RGCA into and out of the fuel assemblies . If needed for core shutdown, the RCGAs can also be released to allow them to drop into the fuel assembly. The individual rodlets are guided inside the CRGTs by approximately one-inch-thick guide cards . The guide cards are located about one foot apart and .
are guided by a continuous guidance assembly located at the bottom of the lower CRGT assembly. Guide card wear is a primary concern due to the possibility of the loss of guidance for the control rodlets inside of a CRGT. The unsupported length of a rodlet will increase if a loss of guidance occurs .
The current CRGT guide card inspection frequency is driven by WGAP-17451-P, Revision 1 by reference in MRP-227 Rev. 1-A for implementation of the CRGT guide card exams, and in WCAP-17096-NP-A, Rev. 2 for acceptable evaluation methodologies. Both documents are the latest NRG-approved documents. MRP-227 Rev. 1-A states GRGT guide card re-inspections may have, "flexible subsequent examination regimens correlating to initial baseline sample size, accuracy of wear estimation, and examination results", [Ref. 3]. In WGAP-17451-P Revision 1, the re-inspection interval for CRGT guide card inspections is limited to 10 years . However, the industry approved a 20 EFPY maximum re-inspection frequency in Rev. 2 of WCAP-17451-P, and it is referenced in MRP-227 Rev. 2. MRP-227 Rev. 2 is currently being reviewed by the NRG.
Similarly, the Rev. 2 ofWCAP-17451-P is referenced in WCAP-17096-NP Rev. 3, which is also currently being reviewed by the NRC.
During the spring 2023 outage, Point Beach Unit 2 plans to perform a full core offload and plans to complete VT-3 and EVT-1 visual examinations of the reactor vessel and internals along with ultrasonic
. testing (UT) examinations of the baffle former bolts in accordance with MRP-227 Rev. 1-A. The GRGT guide card inspections are not planned since a technical justification using the guidance in WGAP-17451-P Revision 2 supports a 20 EFPY re-inspection interval. It was also anticipated the new methodology would be endorsed by the NRC via reference in WGAP-17096-NP Rev. 3 before the spring 2023 refueling outage (P2 R39). The CRGT gu ide card inspections add an additional level of risk in the spring 2023 refuel outage associated with coordination and execution of the large scope of inspection activities. There is significant added cost without any technical benefit. Deferring the CRGT guide card inspections to the 2033 refueling outage (P2 R46) or within 20 EFPY from the spring 2014 refueling outage, facilitates a favorable outage work risk profile and cost with no compromise on safety.
The appropriateness of the 20 EFPY frequency allowed by Revision 2 of WCAP-17451-P was evaluated by WCAP-18494, Revision 0 [Ref. 7], which evaluated wear measurements obtained during the P2R33 outage utilizing the methodology of WCAP-17096, Revision 3. This evaluation confirmed that the wear projection methodology resulted in an acceptable level of margin for all CRGT guide cards after applying an additional 20 EFPY from the date of the P2R33 wear measurements.
As part of the ongoing review for WCAP-17096-NP, Revision 3 [Ref. 5], the U.S. Nuclear Regulatory Commission (NRC) is currently reviewing WCAP-17451-P, Revision 2, which allows for a re-inspection interval of up to 20 EFPY. The intent for the Point Beach GGWM re-inspection plan is to use the 20 EFPY maximum re-inspection interval per WGAP-17451-P, Revision 2. Point Beach Unit 2's current operating license expires March 8, 2033; however, Point Beach has submitted a subsequent license renewal (SLR) application , which may extend the license an additional 20 years or until March 8, 2053. This would place
the CRGT guide card re-inspections during the subsequent period of operation (SPEO). Due to delay of the NRC's review *ofWCAP-17096-NP, Revision 3 and anticipated endorsement ofWCAP-17451-P, Revision 2 via reference in WCAP-17096-NP, Revision 3, Point Beach U2 requires a deviation from the 10-year re-inspection interval specified in WCAP-17451-P, Revision 1.
Conclusion/Findings:
This deviation documents deferral of the Point Beach Unit 2 CRGT guide card inspections from *10 EFPY to 20 EFPY from the spring 2014 refueling outage by applying the latest industry approved CRGT guide card evaluation methodology, WCAP-17451-P Revision 2. It is anticipated that this WCAP will be endorsed by the NRC within the next year via review and approval of WCAP-17096-NP Rev. 3, at which point this deviation will no longer be needed.
References:
- 1. WCAP-17451-P Revision 1, "Reactor Internals Guide Tube Wear- Westinghouse Domestic Fleet Operational Projections," October 2013.
- 2. WCAP-17451-P Revision 2, "Reactor Internals Guide Tube Wear-Westinghouse Domestic Fleet Operational Projections," November 2018.
- 3. MRP-227, Revision 1-A, "Materials Reliability Program: Pressurized Water Reactor Internals Inspection and Evaluation Guidelines", Product ID 3002017168, December 2019.
- 4. WCAP-17096-NP-A, Revision 2, "Reactor Internals Acceptance Criteria Methodology and Data Requirements," August 2016
- 5. WCAP-17096-NP, Revision 3, "Reactor Internals Acceptance Criteria Methodology and Data Requirements," July 2019
- 6. NEI 03-08, Revision 4, "Guideline for Management of Materials Issues," October 2020.
- 7. WCAP-18494-P, Revision 0, Point Beach Unit 2 - Upper Internals 14x14 Guide Tube -
Guide Card Wear Evaluation; December, 2019.
- 8. PBN-2FJF-21-126; Point Beach Unit 2 Cycle 39 Reload EC - Vessel Fluence Assessment; August 6, 2021.
- 9. AR 2415348, PB-1 CRGT Guide Card NEI 03-08 Deviation Prepared By: =S.:...:.h=an=e==-W..:....:....::e=b=b'-/---=-)L
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Technical Review: Ronald L. Barker Jr./
Programs Director Approval: =D-=o-'-'n-'C=h.:..::u::.:..r=ch=/___,~c,,,c-+.r-
. -'-'---;,,d="""-L-""'-r.,o<..,;~.,.---=0=1-~_.;J.._:;,._-::i~0~;1.,._.3 Site Eng. Director Approval: Chad Mynhier/ Chad myn h ,er
- ' Digitally signed by chad mynhier DN: cn=chad mynhier, o=PBN, ou, email=chad.mynhier@fpl.com,c=US
. Date: 2023.01.27 14:40:59 -05'00'
,=;,_.,.....__ Dlg!tally signed by 1-US0WJX DN:cn=t.VSOWJX.
emall"'Mlchael5trope@nexterae Site VP Approval:* Michael Strope/ ~ ~~,t~i~2~.01.2116:s!l<l~-06*00*
Fleet Executive Approval: =D~a"""'n-=Dc....:e:...=Bc....:oc..=e-'-'r/_-"={),,,.,,__o--
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NRC Notification Required? Yes, Letter Number# See AR 2445846-01 IP Notification Required? Yes, Letter Number # __S=-e=e=--A:,__:_:__;R'--=2=--4'-'4-=5-"-8-'-46-"---=0=2_ _ __