Text

Fifth Ten-Year Inservice Inspection Interval Revised Relief Request Nos. 8 and 9 Proposed Alternative in Accordance with 10 CFR 50.55a(z)(l), Extension of Inspection Interval for Turkey Point Units 3 and 4 Reactor Pressure
	ML21134A151
Person / Time
Site:	Turkey Point
Issue date:	05/13/2021
From:	Hess R; Florida Power & Light Co
To:	; Document Control Desk, Office of Nuclear Reactor Regulation
Shared Package
ML21134A150	List: L-2021-107, Fifth Ten-Year Inservice Inspection Interval Revised Relief Request Nos. 8 and 9 Proposed Alternative in Accordance with 10 CFR 50.55a(z)(l), Extension of Inspection Interval for Turkey Point Units 3 and 4 Reactor Pressure;
References
	L-2021-107
	Download: ML21134A151 (22)
	v • d • e

F=PL ..

MAY 1 3 2021 L-2021-107 10 CFR 50.55a 10 CFR 2.390 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D. C. 20555-0001 Re: Turkey Point Unit 3 and Unit 4 Docket Nos. 50-250 and 50-251 Subsequent Renewed License No. DPR-31 Fifth Ten-Year Inservice Inspection Interval Revised Relief Request Nos. 8 and 9 Proposed Alternative in Accordance with 10 CFR 50.55a(z)(l), Extension of Inspection Interval for Turkey Point Unit 3 and Unit 4 Reactor Pressure Vessel Welds from 10 to 20 Years In accordance with the provisions of 10 CFR 50.55a(z)(l), Florida Power & Light Company (FPL) requests approval to extend the Inservice inspection interval for the Turkey Point Units 3 and 4 reactor pressure vessel (RPV) welds from 2023 to 2033 for Unit 3 and 2034 for Unit 4. FPL proposes to implement an alternative to the requirement of ASME Section XI IWB-2411, Inspection Program, that volumetric examination of RPV Examination categories B-A and B-D be performed once each 10-year ISI interval. The cmrent Fifth Ten-Year Inservice Inspection (ISI) interval ends on Februaiy 21, 2024 for Unit 3 and April 14, 2024 for Unit 4. FPL proposes to

<-perform the fifth ASME Section XI Category B-A and B-D examinations in the sixth ISI interval no later than 2033 for Unit 3 and 2034 for Unit 4.

The enclosed Relief Requests 8 and 9, for Turkey Point Units 3 and 4 respectively, contain proprietaiy information. Enclosure 1 contains the nonproprietaiy Relief Requests 8 and 9, in Attachments 1 and 2 respectively. The pages which contain the proprietaiy info1mation are submitted in Enclosure 2, in Attachments 1 and 2 for Relief Requests 8 and 9, respectively.

Together Enclosures 1 and 2 provide the basis and supporting information for the proposed alternative.

Enclosure 3 contains the Affidavit of Gayle Elliott, the Director of Licensing and Regulato1y Affairs, for Framatome Inc. (Framatome) ce1tifying that the material provided in Attachments 1 and 2 are proprietaiy in nature and FPL requests that the material in Enclosure 2 Attachments 1 and 2 be withheld from public disclosure under the provisions of 10 CFR 2.390, Public Inspections, Exemptions, Requests for Withholding.

FPL requests NRC review and approval of the proposed alternative by May 2022 to supp01t the use of the proposed alternative during the refueling outage in the fall of 2023.

Florida Power & Light Company 9760 S.W. 344th Street Homestead, FL 33035

L-2021-107 Enclosure 1, Attachment 1 Page 1 L-2021-107 Turkey Point Unit 3 Enclosure 1 Non-Proprietary Submission Attachment 1 Relief Request Number RR8 Proposed Alternative for the Extension of Turkey Point Unit 3 RPV Welds from 10 to 20 Years In Accordance with 10 CFR 50.55a(z)(1)

L-2021-107 Enclosure 1, Attachment 1 Page 2 Relief Request RR8 Proposed Alternative for the Extension of Turkey Point Unit 3 RPV Welds from 10 to 20 Years In Accordance with 10 CFR 50.55a(z)(1)

-Alternative Provides Acceptable Level of Quality and Safety-

1. ASME Code Component(s) Affected The affected component is the Turkey Point Unit 3 reactor vessel (RV), specifically, the following American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel (BPV)

Code,Section XI (Reference 1) examination categories and item numbers covering examinations of the RV. These examination categories and item numbers are from IWB-2500 and Table IWB-2500-1 of the ASME BPV Code,Section XI.

Category B-A welds are defined as Pressure Retaining Welds in Reactor Vessel.

Category B-D welds are defined as Full Penetration Welded Nozzles in Vessels.

Examination Category Item No. Description B-A B1.10 Shell Welds B-A B1.11 Circumferential Shell Welds B-A B1.20 Head Welds B-A B1.21 Circumferential Head Welds B-A B1.30 Shell-to-Flange Weld B-D B3.90 Nozzle-to-Vessel Welds B-D B3.100 Nozzle Inside Radius Section (Throughout this request, the above examination categories are referred to as the subject examinations and the ASME BPV Code,Section XI, is referred to as the Code.)

2. Applicable Code Edition and Addenda

ASME Code Section XI, Rules for Inservice Inspection of Nuclear Power Plant Components, 2007 Edition though 2008 Addenda (Reference 1).

3. Applicable Code Requirement

IWB-2411, Inspection Program, requires volumetric examination of essentially 100% of reactor vessel pressure-retaining welds identified in Table IWB-2500-1 once each 10-year interval. The Turkey Point Unit 3 fifth 10-year Inservice inspection (ISI) interval is scheduled to end on February

L-2021-107 Enclosure 1, Attachment 1 Page 3 21, 2024. The applicable Code for the sixth 10-year ISI interval will be selected in accordance with the requirements of 10 CFR 50.55a.

4. Reason for Request

An alternative is requested from the requirement of the IWB-2411 Inspection Program, that volumetric examination of essentially 100% of reactor vessel pressure-retaining Examination Category B-A and B-D welds be performed once each 10-year interval. Extension of the interval between examinations of Category B-A and B-D welds from 10 years to up to 20 years will result in a reduction in man-rem exposure and examination costs.

5. Proposed Alternative and Basis for Use

Florida Power and Light Co. (FPL) proposes not to perform the ASME Code required volumetric examination of the Turkey Point Unit 3 reactor vessel full penetration pressure-retaining Examination Category B-A and B-D welds for the fifth Inservice inspection, currently scheduled for 2023. FPL will perform the fifth ASME Code required volumetric examination of the Turkey Point Unit 3 reactor vessel full penetration pressure-retaining Examination Category B-A and B-D welds in the sixth Inservice inspection interval in 2033. The proposed inspection date is consistent with the latest revised implementation plan, OG-10-238 (Reference 2).

In accordance with 10 CFR 50.55a(z)(1), an alternate inspection interval is requested on the basis that the current interval can be revised with negligible change in risk by satisfying the risk criteria specified in Regulatory Guide 1.174 (Reference 3).

The methodology used to conduct this analysis is based on that defined in the study WCAP-16168-NP-A, Revision 3, Risk-Informed Extension of the Reactor Vessel In-service Inspection Interval (Reference 4). This study focuses on risk assessments of materials within the beltline region of the RV wall. The results of the calculations for Turkey Point Unit 3 were compared to those obtained from the Westinghouse pilot plant evaluated in WCAP-16168-NP-A, Revision 3.

Appendix A of the WCAP identifies the parameters to be compared. Demonstrating that the parameters for Turkey Point Unit 3 are bounded by the results of the Westinghouse pilot plant qualifies Turkey Point Unit 3 for an ISI interval extension.

L-2021-107 Enclosure 1, Attachment 1 Page 4 Table 1 below lists the critical parameters investigated in the WCAP and compares the results of the Westinghouse pilot plant to those of Turkey Point Unit 3. Tables 2 and 3 provide additional information that was requested by the NRC and included in Appendix A of Reference 4.

Table 1: Critical Parameters for the Application of Bounding Analysis for Turkey Point Unit 3 Plant-Specific Additional Parameter Pilot Plant Basis Evaluation Basis Required?

Dominant Pressurized Thermal NRC PTS Risk Shock (PTS) Transients in the PTS Generalization Study No NRC PTS Risk Study are Study (Reference 6)

(Reference 5)

Applicable 1.76E-08 Events (( ))

Through-Wall Cracking Frequency Events per year per year No (TWCF) (Calculated per (Reference 4)

Reference 4) 7 heatup/cooldown Bounded by 7 Frequency and Severity of Design cycles per year heatup/cooldown No Basis Transients (Reference 4) cycles per year Single Layer Cladding Layers (Single/Multiple) Single Layer No (Reference 4)

Table 2 below provides a summary of the latest reactor vessel inspection for Turkey Point Unit 3 and an evaluation of the recorded indications. This information confirms that satisfactory examinations have been performed on the Turkey Point Unit 3 reactor vessel.

L-2021-107 Enclosure 1, Attachment 1 Page 5 Table 2: Additional Information Pertaining to Reactor Vessel Inspection for Turkey Point Unit 3 The latest ISI for Turkey Point Unit 3 was conducted in accordance with the ASME Code,Section XI, 1998 Edition, with 2000 Addenda. Examinations of Category B-A and B-D Inspection welds were performed to ASME Section XI, Appendix VIII, 1998 Edition with 2000 methodology: Addenda as modified by 10 CFR 50.55a(b)(2)(xiv, xv, and xvi). Future Inservice inspections will continue to be performed to ASME Section XI, Appendix VIII methodology.

Number of past Four 10-year Inservice inspections and a preservice inspection have been performed.

inspections:

There were 19 indications identified in the beltline and extended beltline regions of the RV during the most recently completed Inservice inspection. These subsurface indications are located in the upper shell forging to intermediate shell forging circumferential (circ.) weld seam and the intermediate shell forging to lower shell forging circumferential weld seam; all the subsurface indications are acceptable per Table IWB-3510-1 of Section XI of the ASME Code. One of these indications is within the inner 1/10th or 1 inch of the reactor vessel thickness and required further evaluation. This indication is acceptable per the requirements of the Alternate PTS Rule, 10 CFR 50.61a (Reference 7).

A disposition of the flaw against the limits of the Alternate PTS Rule is shown in the table below. The flaw is located within the forging material of the reactor vessel.

Through-Wall Extent, Scaled Maximum number of flaws per 3793 Number of TWE (in) square-inches of inside surface area in the Turkey inspection volume that are greater than or Point Unit 3 TWEMIN TWEMAX equal to TWEMIN and less than TWEMAX. Flaws This flaw density does not include Evaluated underclad cracks in forgings. (Axial/Circ.)

Number of indications found: 0 0.075 No Limit 0 0.075 0.375 30 1 (0/1) 0.125 0.375 11 0 0.175 0.375 3 0 0.225 0.375 1 0 0.275 0.375 0 0 0.325 0.375 0 0 0.375 Infinite 0 0 The plant-specific total surface area (3793 square-inches) of reactor vessel beltline forgings that were volumetrically inspected are comprised of the intermediate to lower shell forgings circumferential weld. While the upper shell to intermediate shell forging circumferential weld and the lower shell forging to lower head ring circumferential weld were inspected and evaluated, the area associated with these welds are conservatively excluded from the calculation of the total inspected area.

Proposed The fifth Inservice inspection is currently scheduled for 2023. This inspection will instead inspection schedule be performed during the 2033 refueling outage. The proposed inspection date is for balance of plant consistent with the latest revised implementation plan OG-10-238 (Reference 2).

life:

L-2021-107 Enclosure 1, Attachment 1 Page 6 Table 3 summarizes the inputs and outputs for the calculation of through-wall cracking frequency (TWCF).

Table 3: Details of TWCF Calculation for Turkey Point Unit 3 at 72 Effective Full Power Years (EFPY)

Inputs (1)

Twall [inches]: 9.156 2

Material Copper Nickel R.G. 1.99 Chemistry RTNDT(u) Fluence (n/cm ,

No. Region and Component Description Identification (weight %) (weight %) Position Factor (ºF) (ºF) E > 1.0 MeV) 1 Upper Shell Forging 122S146VA1 (( )) 0.68 1.1 (( )) 50 1.13E+19 2 Intermediate Shell Forging 123P461VA1 0.058 0.70 1.1 37 40 1.08E+20 3 IS Forging using Surveillance Data 123P461VA1 0.058 0.70 2.1 6.9 40 1.08E+20 4 Lower Shell Forging 123S266VA1 0.079 0.67 1.1 51 30 9.86E+19 5 LS Forging using Surveillance Data 123S266VA1 0.079 0.67 2.1 48.7 30 9.86E+19 6 Lower Head Ring (Transition) ZV-2785 (( )) 0.69 1.1 (( )) (( )) 1.36E+17 7 Upper Shell to Intermediate Shell Weld SA-1484 0.26 0.60 1.1 180 -33.2 1.13E+19 8 Intermediate Shell to Lower Shell Weld SA-1101 0.23 0.59 1.1 167.6 -53.5 9.86E+19 9 IS to LS Weld Surveillance Data SA-1101 0.23 0.59 2.1 151.1 -53.5 9.86E+19 10 Lower Shell to Lower Head Ring Weld SA-1135 0.23 0.52 1.1 157.4 (( )) 1.36E+17 Outputs Methodology Used to Calculate T30: Regulatory Guide 1.99, Revision 2 (Reference 8)

Controlling Fluence FF Material Region RTMAX-XX 2 (n/cm , E >1.0 (Fluence T30 (ºF) TWCF95-XX xx (°R)

No. (From Above) MeV) Factor)

Limiting Axial Weld - AW N/A - - - - - -

Limiting Plate - PL N/A - - - - - -

Limiting Circumferential Weld - CW 8 2.2927 659.55 9.86E+19 1.5118 253.38 5.211E-14 Limiting Forging - FO 1 2.5 (( )) 1.13E+19 1.0341 (( )) (( ))

TWCF95-TOTAL = (AWTWCF95-AW + PLTWCF95-PL + CWTWCF95-CW + FOTWCF95-FO): (( ))

1. Material properties and fluence inputs are based on the subsequent license renewal application (Reference 9) and Framatome Letter (Reference 10).

L-2021-107 Enclosure 1, Attachment 1 Page 7

6. Duration of Proposed Alternative

This request is applicable to the Turkey Point Unit 3 Inservice inspection program for the Fifth and Sixth 10-year inspection intervals.

7. Precedents

1. Surry Power Station Units 1 and 2 - Relief Implementing Extended Reactor Vessel Inspection Interval (TAC Nos. ME8573 and ME8574), dated April 30, 2013, Agencywide Document Access and Management System (ADAMS) Accession Number ML13106A140.

2. Vogtle Electric Generating Plant, Units 1 and 2 - Request for Alternatives VEGP-ISI-ALT-05 and VEGP-ISI-ALT-06 (TAC Nos. MF2596 and MF2597), dated March 20, 2014, ADAMS Accession Number ML14030A570.

3. Catawba Nuclear Station Units 1 and 2: Proposed Relief Request 13-CN-003, Request for Alternative to the Requirement of IWB-2500, Table IWB-2500-1, Category B-A and Category B-D for Reactor Pressure Vessel Welds (TAC Nos. MF1922 and MF1923), dated March 26, 2014, ADAMS Accession Number ML14079A546.

4. Sequoyah Nuclear Plant, Units 1 and 2 - Requests for Alternatives 13-ISI-1 and 13-ISI-2 to Extend the Reactor Vessel Weld Inservice Inspection Interval (TAC Nos. MF2900 and MF2901), dated August 1, 2014, ADAMS Accession Number ML14188B920.

5. Byron Station, Unit No. 1 - Relief from Requirements of the ASME Code to Extend the Reactor Vessel Inservice Inspection Interval (TAC No. MF3596), dated December 10, 2014, ADAMS Accession Number ML14303A506.

6. Wolf Creek Generating Station - Request for Relief Nos. I3R-08 and I3R-09 for the Third 10-Year Inservice Inspection Program Interval (TAC Nos. MF3321 and MF3322), dated December 10, 2014, ADAMS Accession Number ML14321A864.

7. Callaway Plant, Unit 1 - Request for Relief I3R-17, Alternative to ASME Code Requirements Which Extends the Reactor Vessel Inspection Interval from 10 to 20 Years (TAC No.

MF3876), dated February 10, 2015, ADAMS Accession Number ML15035A148.

8. Braidwood Station, Units 1 and 2 - Request for Relief from the Requirements of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME Code) (CAC Nos.

MF8191 and MF8192), dated March 15, 2017, ADAMS Accession Number ML17054C255.

9. South Texas Project, Units 1 and 2 - Relief from the Requirements of the ASME Code Regarding the Third 10-Year Inservice Inspection Program Interval (EPID L-2018-LLR-0010),

dated July 24, 2018, ADAMS Accession Number ML18177A425.

10. Donald C. Cook Nuclear Plant, Unit No. 1 - Approval of Alternative to the ASME Code Regarding Reactor Vessel Weld Examination - Relief Request ISIR-4-08 (EPID: L-2018-LLR-0106), dated October 26, 2018, ADAMS Accession Number ML18284A310.

L-2021-107 Enclosure 1, Attachment 1 Page 8

11. R. E. Ginna Nuclear Power Plant - Issuance of Relief Request ISI-18 Regarding Fifth 10-year Inservice Inspection Program Interval (EPID L-2018-LLR-0104), dated April 22, 2019, ADAMS Accession Number ML19100A004.

12. Point Beach Nuclear Plant, Units 1 and 2 - Approval of Relief Requests 1-RR-13 and 2-RR-13 Regarding Extension of Inspection Interval for Reactor Pressure Welds from 10 to 20 years (EPID L-2019-LLR-0060), dated March 4, 2020, ADAMS Accession Number ML20036F261.

8. References

1. ASME Boiler and Pressure Vessel Code,Section XI, 2007 Edition through 2008 Addenda, American Society of Mechanical Engineers, New York.

2. PWROG Letter OG-10-238, Revision to the Revised Plan for Plant Specific Implementation of Extended Inservice Inspection Interval per WCAP-16168-NP, Revision 1, Risk-Informed Extension of the Reactor Vessel In-Service Inspection Interval. PA-MSC-0120, July 12, 2010 (ADAMS Accession Number ML11153A033).

3. NRC Regulatory Guide 1.174, Revision 1, An Approach for Using Probabilistic Risk Assessment in Risk-Informed Decisions on Plant-Specific Changes to the Licensing Basis, U.S. Nuclear Regulatory Commission, November 2002, (ADAMS Accession Number ML023240437).

4. Westinghouse Report, WCAP-16168-NP-A, Revision 3, Risk-Informed Extension of the Reactor Vessel In-service Inspection Interval, October 2011 (ADAMS Accession Number ML11306A084).

5. NUREG-1874, Recommended Screening Limits for Pressurized Thermal Shock (PTS), U.S.

Nuclear Regulatory Commission, March 2010, (ADAMS Accession Number ML15222A848).

6. NRC Letter Report, Generalization of Plant-Specific Pressurized Thermal Shock (PTS) Risk Results to Additional Plants, U.S. Nuclear Regulatory Commission, December 14, 2004 (ADAMS Accession Number ML042880482).

7. Code of Federal Regulations, 10 CFR Part 50.61a, Alternate Fracture Toughness Requirements for Protection Against Pressurized Thermal Shock Events, U.S. Nuclear Regulatory Commission, Washington D. C., Federal Register, Volume 75, No. 1, dated January 4, 2010 and No. 22 with corrections to part (g) dated February 3, 2010, March 8, 2010, and November 26, 2010.

8. NRC Regulatory Guide 1.99, Revision 2, Radiation Embrittlement of Reactor Vessel Materials, U.S. Nuclear Regulatory Commission, May 1988, (ADAMS Accession Number ML003740284).

9. Subsequent License Renewal Application, Docket Nos. 50-250 and 50-251, L-2018-082 Enclosure 3, Turkey Point Nuclear Plant Units 3 and 4 Subsequent License Renewal Application, Revision 1, April 2018, (ADAMS Accession Number ML18113A146)

10. Framatome Letter, 20-01243, Framatome Inc. Proprietary Reactor Vessel Data to Support Turkey Point Units 3 & 4 for MSC-0943, May 29, 2020.

L-2021-107 Page 2 This letter contains no new regulatory commitments or revisions to existing regulatory commitments If you have any questions or require additional information, please contact Robert J. Hess, Licensing Manager, at (305) 246-4112.

Sincerely, Licensin Manager Turkey Point Nuclear Plant Enclosures Attachments cc: USNRC Regional Administrator, Region II, USNRC USNRC Senior Resident Inspector, USNRC, Turkey Point Nuclear Plant USNRC Project Manager, Turkey Point Nuclear Plant

L-2021-107 Enclosure 1, Attachment 2 Page 1 L-2021-0107 Enclosure 1 Non-Proprietary Submission Attachment 2 Relief Request Number RR9 Proposed Alternative for the Extension of Turkey Point Unit 4 RPV Welds from 10 to 20 Years In Accordance with 10 CFR 50.55a(z)(1)

L-2021-107 Enclosure 1, Attachment 2 Page 2 Relief Request Number RR9 Proposed Alternative for the Extension of Turkey Point Unit 4 RPV Welds from 10 to 20 Years In Accordance with 10 CFR 50.55a(z)(1)

-Alternative Provides Acceptable Level of Quality and Safety-

1. ASME Code Component(s) Affected The affected component is the Turkey Point Unit 4 reactor vessel (RV), specifically, the following American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel (BPV)

Code,Section XI (Reference 1) examination categories and item numbers covering examinations of the RV. These examination categories and item numbers are from IWB-2500 and Table IWB-2500-1 of the ASME BPV Code,Section XI.

Category B-A welds are defined as Pressure Retaining Welds in Reactor Vessel.

Category B-D welds are defined as Full Penetration Welded Nozzles in Vessels.

Examination Category Item No. Description B-A B1.10 Shell Welds B-A B1.11 Circumferential Shell Welds B-A B1.20 Head Welds B-A B1.21 Circumferential Head Welds B-A B1.30 Shell-to-Flange Weld B-D B3.90 Nozzle-to-Vessel Welds B-D B3.100 Nozzle Inside Radius Section (Throughout this request, the above examination categories are referred to as the subject examinations and the ASME BPV Code,Section XI, is referred to as the Code.)

2. Applicable Code Edition and Addenda

ASME Code Section XI, Rules for Inservice Inspection of Nuclear Power Plant Components, 2007 through 2008 Addenda Edition (Reference 1).

3. Applicable Code Requirement

IWB-2411, Inspection Program, requires volumetric examination of essentially 100% of reactor vessel pressure-retaining welds identified in Table IWB-2500-1 once each 10-year interval. The Turkey Point Unit 4 fifth 10-year inservice inspection (ISI) interval is scheduled to end on April 14, 2024. The applicable Code for the sixth 10-year ISI interval will be selected in accordance with the requirements of 10 CFR 50.55a.

L-2021-107 Enclosure 1, Attachment 2 Page 3

4. Reason for Request

An alternative is requested from the requirement of the IWB-2411 Inspection Program, that volumetric examination of essentially 100% of reactor vessel pressure-retaining Examination Category B-A and B-D welds be performed once each 10-year interval. Extension of the interval between examinations of Category B-A and B-D welds from 10 years to up to 20 years will result in a reduction in man-rem exposure and examination costs.

5. Proposed Alternative and Basis for Use

Florida Power and Light Co. (FPL) proposes not to perform the ASME Code required volumetric examination of the Turkey Point Unit 4 reactor vessel full penetration pressure-retaining Examination Category B-A and B-D welds for the fifth inservice inspection, currently scheduled for 2023. FPL will perform the fifth ASME Code required volumetric examination of the Turkey Point Unit 4 reactor vessel full penetration pressure-retaining Examination Category B-A and B-D welds in the sixth inservice inspection interval in 2034. The proposed inspection date is consistent with the latest revised implementation plan, OG-10-238 (Reference 2).

In accordance with 10 CFR 50.55a(z)(1), an alternate inspection interval is requested on the basis that the current interval can be revised with negligible change in risk by satisfying the risk criteria specified in Regulatory Guide 1.174 (Reference 3).

The methodology used to conduct this analysis is based on that defined in the study WCAP-16168-NP-A, Revision 3, Risk-Informed Extension of the Reactor Vessel In-service Inspection Interval (Reference 4). This study focuses on risk assessments of materials within the beltline region of the RV wall. The results of the calculations for Turkey Point Unit 4 were compared to those obtained from the Westinghouse pilot plant evaluated in WCAP-16168-NP-A, Revision 3.

Appendix A of the WCAP identifies the parameters to be compared. Demonstrating that the parameters for Turkey Point Unit 4 are bounded by the results of the Westinghouse pilot plant qualifies Turkey Point Unit 4 for an ISI interval extension.

L-2021-107 Enclosure 1, Attachment 2 Page 4 Table 1 below lists the critical parameters investigated in the WCAP and compares the results of the Westinghouse pilot plant to those of Turkey Point Unit 4. Tables 2 and 3 provide additional information that was requested by the NRC and included in Appendix A of Reference 4.

Table 1: Critical Parameters for the Application of Bounding Analysis for Turkey Point Unit 4 Additional Plant-Specific Parameter Pilot Plant Basis Evaluation Basis Required?

Dominant Pressurized Thermal Shock NRC PTS Risk Study PTS Generalization (PTS) Transients in the NRC PTS No (Reference 5) Study (Reference 6)

Risk Study are Applicable Through-Wall Cracking Frequency 1.76E-08 Events per (( )) Events per year (Calculated No (TWCF) year (Reference 4) per Reference 4)

Frequency and Severity of Design 7 heatup/cooldown Bounded by 7 cycles per year heatup/cooldown No Basis Transients (Reference 4) cycles per year Cladding Layers (Single/Multiple) Single Layer Single Layer No (Reference 4)

L-2021-107 Enclosure 1, Attachment 2 Page 5 Table 2 below provides a summary of the latest reactor vessel inspection for Turkey Point Unit 4 and an evaluation of the recorded indications. This information confirms that satisfactory examinations have been performed on the Turkey Point Unit 4 reactor vessel.

Table 2: Additional Information Pertaining to Reactor Vessel Inspection for Turkey Point Unit 4 The latest ISI for Turkey Point Unit 4 was conducted in accordance with the Inspection methodology: ASME Code,Section XI, 1998 Edition, with 2000 Addenda. Examinations of Category B-A and B-D welds were performed to ASME Section XI, Appendix VIII, 1998 Edition with 2000 Addenda as modified by 10 CFR 50.55a(b)(2)(xiv, xv, and xvi). Future Inservice inspections will continue to be performed to ASME Section XI, Appendix VIII methodology.

Number of past Four 10-year Inservice inspections and a preservice inspection have been inspections: performed.

There were 26 indications identified in the beltline and extended beltline Number of indications regions of the RV during the most recently completed Inservice inspection. One found:

of these indications is a surface indication on the outside surface of the RV and the other 25 indications are subsurface indications. The 26 indication are located in the upper shell forging to intermediate shell forging circumferential (circ.) weld seam, the intermediate shell forging to lower shell forging circumferential weld seam, and the lower shell forging to the lower head ring circumferential weld seam; all the indications are acceptable per Table IWB-3510-1 of Section XI of the ASME Code. None of these indications are within the inner 1/10th or 1 inch of the reactor vessel thickness.

Therefore, the Inservice inspection results inherently satisfy the requirements of the Alternate PTS Rule, 10 CFR 50.61a (Reference 7).

Proposed inspection The Fifth Inservice inspection is currently scheduled for 2023. This inspection schedule for balance of is proposed to be performed during the 2034 refueling outage. The proposed plant life: inspection date is consistent with the latest revised implementation plan, OG-10-238 (Reference 2).

L-2021-107 Enclosure 1, Attachment 2 Page 6 Table 3 summarizes the inputs and outputs for the calculation of through-wall cracking frequency (TWCF).

Table 3: Details of TWCF Calculation for Turkey Point Unit 4 at 72 Effective Full Power Years (EFPY)

Inputs (1)

Twall [inches]: 9.156 2

Material Copper Nickel R.G. 1.99 Chemistry RTNDT(u) Fluence (n/cm ,

No. Region and Component Description Identification (weight %) (weight %) Position Factor (ºF) (ºF) E > 1.0 MeV) 1 Upper Shell Forging 124S309VA1 (( )) 0.70 1.1 (( )) 40 1.15E+19 2 Intermediate Shell Forging 123P481VA1 0.054 0.69 1.1 33.4 50 1.08E+20 3 Lower Shell Forging 122S180VA1 0.056 0.74 1.1 34.6 40 9.81E+19 4 LS Forging using Surveillance Data 122S180VA1 0.056 0.74 2.1 4.9 40 9.81E+19 5 Lower Head Ring (Transition) ZV-2743 (( )) 0.69 1.1 (( )) (( )) 1.36E+17 Upper Shell to Intermediate Shell Weld 6 (Inner 67%) WF-67 0.26 0.60 1.1 180 -33.2 1.15E+19 Upper Shell to Intermediate Shell Weld 7 (Outer 33%) WF-70 0.32 0.58 1.1 199.3 -31.1 1.15E+19 8 Intermediate Shell to Lower Shell Weld SA-1101 0.23 0.59 1.1 167.6 -53.5 9.81E+19 9 IS to LS Weld using Surveillance Data SA-1101 0.23 0.59 2.1 151.1 -53.5 9.81E+19 10 Lower Shell to Lower Head Ring Weld SA-1135 0.23 0.52 1.1 157.4 (( )) 1.36E+17 Outputs Methodology Used to Calculate T30: Regulatory Guide 1.99, Revision 2 (Reference 8)

Controlling Fluence FF Material Region RTMAX-XX (n/cm 2

, E (Fluence xx (°R) T30 (ºF) TWCF95-XX No. (From Above) >1.0 MeV) Factor)

Limiting Axial Weld - AW N/A - - - - - -

Limiting Plate - PL N/A - - - - - -

Limiting Circumferential Weld - CW 8 2.2933 659.45 9.81E+19 1.5112 253.28 5.097E-14 Limiting Forging - FO 1 2.5 (( )) 1.15E+19 1.0390 (( )) (( ))

TWCF95-TOTAL = (AWTWCF95-AW + PLTWCF95-PL + CWTWCF95-CW + FOTWCF95-FO): (( ))

1. Material properties and fluence inputs are based on the subsequent license renewal application (Reference 9) and Framatome Letter (Reference 10).

L-2021-107 Enclosure 1, Attachment 2 Page 7

6. Duration of Proposed Alternative

This request is applicable to the Turkey Point Unit 4 Inservice inspection program for the Fifth and Sixth 10-year inspection intervals.