ML20259A298

Issuance of Amendment No. 205 Regarding Modification of the Reactor Coolant Pump Flywheel Inspection Program

ML20259A298
Person / Time
Site:	Saint Lucie
Issue date:	11/18/2020
From:	Natreon Jordan Plant Licensing Branch II
To:	Moul D Florida Power & Light Co
Jordan N
References
EPID L-2019-LLA-0227
Download: ML20259A298 (14)

Text

November 18, 2020 Mr. Don Moul Executive Vice President, Nuclear Division and Chief Nuclear Officer Florida Power & Light Company Mail Stop: EX/JB 700 Universe Blvd.

Juno Beach, FL 33408

SUBJECT:

ST. LUCIE PLANT, UNIT NO. 2 - ISSUANCE OF AMENDMENT NO. 205 REGARDING MODIFICATION OF THE REACTOR COOLANT PUMP FLYWHEEL INSPECTION PROGRAM (EPID L-2019-LLA-0227)

Dear Mr. Moul:

The U.S. Nuclear Regulatory Commission (NRC or the Commission) has issued the enclosed Amendment No. 205 to Renewed Facility Operating License No. NPF-16 for the St. Lucie Plant, Unit No. 2, in response to your application dated October 9, 2019, as supplemented by letters dated April 30, 2020, and June 26, 2020.

The amendment modifies the St. Lucie Plant, Unit No. 2, Technical Specifications by revising the Reactor Coolant Pump Flywheel Inspection Program requirements to be consistent with the conclusions and limitations specified in the NRC safety evaluation of Topical Report SIR-94-080, Relaxation of Reactor Coolant Pump Flywheel Inspection Requirements, dated May 21, 1997.

A copy of the related safety evaluation is also enclosed. Notice of Issuance will be included in the Commissions monthly Federal Register notice.

Sincerely,

/RA/

Natreon J. Jordan, Project Manager Plant Licensing Branch II-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-389

Enclosures:

1. Amendment No. 205 to NPF-16

2. Safety Evaluation cc: Listserv

FLORIDA POWER & LIGHT COMPANY ORLANDO UTILITIES COMMISSION OF THE CITY OF ORLANDO, FLORIDA AND FLORIDA MUNICIPAL POWER AGENCY DOCKET NO. 50-389 ST. LUCIE PLANT UNIT NO. 2 AMENDMENT TO RENEWED FACILITY OPERATING LICENSE Amendment No. 205 Renewed License No. NPF-16

1. The U.S. Nuclear Regulatory Commission (the Commission) has found that:

A. The application for amendment by Florida Power & Light Company dated October 9, 2019, as supplemented by letters dated April 30, 2020, and June 26, 2020, complies with the standards and requirements of the Atomic Energy Act of 1954, as amended (the Act), and the Commissions rules and regulations set forth in 10 CFR Chapter I; B. The facility will operate in conformity with the application, the provisions of the Act, and the rules and regulations of the Commission; C. There is reasonable assurance (i) that the activities authorized by this amendment can be conducted without endangering the health and safety of the public, and (ii) that such activities will be conducted in compliance with the Commissions regulations; D. The issuance of this amendment will not be inimical to the common defense and security or to the health and safety of the public; and E. The issuance of this amendment is in accordance with 10 CFR Part 51 of the Commissions regulations and all applicable requirements have been satisfied.

Enclosure 1

2. Accordingly, by Amendment No. 205, Renewed Facility Operating License No. NPF-16 is amended by changes to the Technical Specifications as indicated in the attachment to this license amendment, and by amending paragraph 3.B to read as follows:

B. Technical Specifications The Technical Specifications contained in Appendices A and B, as revised through Amendment No. 205, are hereby incorporated in the renewed license. FPL shall operate the facility in accordance with the Technical Specifications.

3. This license amendment is effective as of its date of issuance and shall be implemented within 90 days of issuance.

FOR THE NUCLEAR REGULATORY COMMISSION Digitally signed by Undine Undine S. S. Shoop Date: 2020.11.18 Shoop 16:00:49 -05'00' Undine S. Shoop, Chief Plant Licensing Branch II-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation

Attachment:

Changes to the Renewed Facility Operating License and Technical Specifications Date of Issuance: November 18, 2020

ATTACHMENT TO LICENSE AMENDMENT NO. 205 ST. LUCIE PLANT, UNIT NO. 2 RENEWED FACILITY OPERATING LICENSE NO. NPF-16 DOCKET NO. 50-389 Replace page 3 of Renewed Facility Operating License No. NPF-16 with the attached page 3.

The revised page is identified by amendment number and contains a marginal line indicating the area of change.

Replace the following page of the Appendix A Technical Specifications with the attached page.

The revised page is identified by amendment number and contains marginal lines indicating the area of change.

Remove Insert 6-15j 6-15j

neutron sources for reactor startup, sealed sources for reactor instrumentation and radiation monitoring equipment calibration, and as fission detectors in amounts as required.

D. Pursuant to the Act and 10 CFR Parts 30, 40, and 70, FPL to receive, possess, and use in amounts as required any byproduct, source, or special nuclear material without restriction to chemical or physical form, for sample analysis or instrument calibration or associated with radioactive apparatus or components; and E. Pursuant to the Act and 10 CFR Parts 30, 40, and 70, FPL to possess, but not separate, such byproduct and special nuclear materials as may be produced by the operation of the facility.

3. This renewed license shall be deemed to contain and is subject to the conditions specified in the following Commissions regulations: 10 CFR Part 20, Section 30.34 of 10 FR Part 30, Section 40.41 of 10 CFR Part 40, Section 50.54 and 50.59 of 10 CFR Part 50, and Section 70.32 of 10 CFR Part 70; and is subject to all applicable provisions of the Act and to the rules, regulations, and orders of the Commission now or hereafter in effect; and is subject to the additional conditions specified below:

A. Maximum Power Level FPL is authorized to operate the facility at steady state reactor core power levels not in excess of 3020 megawatts (thermal).

B. Technical Specifications The Technical Specifications contained in Appendices A and B, as revised through Amendment No. 205, are hereby incorporated in the renewed license.

FPL shall operate the facility in accordance with the Technical Specifications.

Renewed License No. NPF-16 Amendment No. 205

ADMINISTRATIVE CONTROLS (continued)

n. Diesel Fuel Oil Testing Program A diesel fuel oil testing program to implement required testing of both new fuel oil and stored fuel oil shall be established. The program shall include sampling and testing requirements, and acceptance criteria, all in accordance with applicable ASTM Standards. The purpose of the program is to establish the following:

(i) Acceptability of new fuel oil for use prior to addition to storage tanks by determining that the fuel oil has:

1. An API gravity or an absolute specific gravity within limits,

2. A flash point and kinematic viscosity within limits for ASTM 2D fuel oil, and

3. A clear and bright appearance with proper color or a water and sediment content within limits; (ii) Other properties for ASTM 2D fuel oil are within limits within 31 days following sampling and addition to storage tanks; and (iii) Total particulate concentration of the fuel oil is 10 mg/l when tested every 31 days.

The provisions of SR 4.0.2 and SR 4.0.3 are applicable to the Diesel Fuel Oil Testing Program test frequencies.

o. Reactor Coolant Pump Flywheel Inspection Program This program shall provide for the inspection of each reactor coolant pump flywheel by either a 100% volumetric inspection of the upper flywheel over the volume from the inner bore of the flywheel to the circle of one-half the outer radius or a surface examination (magnetic particle testing and/or penetrant testing) of exposed surfaces defined by the volume of the disassembled flywheel at least once every 10 years.

p. Snubber Testing Program This program conforms to the examination, testing and service life monitoring for dynamic restraints (snubbers) in accordance with 10 CFR 50.55a inservice inspection (ISI) requirements for supports. The program shall be in accordance with the following:

1. This program shall meet 10 CFR 50.55a(g) ISI requirements for supports.

2. The program shall meet the requirements for ISI of supports set forth in subsequent editions of the Code of Record and addenda of the American Society of Mechanical Engineers (ASME) Boiler and Pressure (BPV) Code and the ASME Code for Operation and Maintenance of Nuclear Power Plants (OM Code) that are incorporated by reference in 10 CFR 50.55a(b) subject to limitations and modifications listed in 10 CFR 50.55a(b) and subject to Commission approval.

3. The program shall, as required by 10 CFR 50.55a(b)(3)(v)(B), meet Subsection ISTA, General Requirements and Subsection ISTD, Preservice and Inservice Examination and Testing of Dynamic Restraints (Snubbers) in Light-Water Reactor Nuclear Power Plants.

4. The 120-month program updates shall be made in accordance with 10 CFR 50.55a(g)(4), 10 CFR 50.55a(g)(3)(v) and 10 CFR 50.55a(b) (including 10 CFR 50.55a(b)(3)(v)(B)) subject to the limitations and modifications listed therein.

ST. LUCIE - UNIT 2 6-15j Amendment No. 155, 159, 169, 205

SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO. 205 TO RENEWED OPERATING LICENSE NO. NPF-16 FLORIDA POWER & LIGHT COMPANY ST. LUCIE PLANT, UNIT NO. 2 DOCKET NO. 50-389

1.0 INTRODUCTION

By letter dated October 9, 2019 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML19282D338), as supplemented by letters dated April 30, 2020, and June 26, 2020 (ADAMS Accession Nos. ML20121A170 and ML20178A463, respectively),

Florida Power & Light Company (FPL, the licensee), submitted to the U.S. Nuclear Regulatory Commission (NRC, the Commission), a license amendment request (LAR) to revise Technical Specification (TS) 6.8.4.o Reactor Coolant Pump Flywheel Inspection Program, for the St. Lucie Nuclear Plant, Unit No. 2 (St. Lucie Unit 2), pursuant to Title 10 of the Code of Federal Regulations (10 CFR) Section 50.90. As discussed in Section 3.1 of this safety evaluation (SE), the licensee proposed to modify the St. Lucie Unit 2 Reactor Coolant Pump (RCP) Flywheel Inspection Program requirements to be consistent with the conclusions and limitations specified in the NRCs May 21, 1997, SE of Topical Report SIR-94-080, Revision 1 Relaxation of Reactor Coolant Pump Flywheel Inspection Requirements (ADAMS Accession No. ML20013C086). 1 The supplements dated April 30, 2020, and June 26, 2020, provided additional information that clarified the application, did not expand the scope of the application as originally noticed, and did not change the NRC staffs original proposed no significant hazards consideration determination as published in the Federal Register on March 24, 2020 (85 FR 16683).

2.0 REGULATORY EVALUATION

The NRC staff (the staff) evaluated the acceptability of the licensees proposed LAR based on the following NRC regulations and guidance. The regulation in 10 CFR 50.36, Technical Specifications, requires that TSs include items in the following categories: (1) safety limits, limiting safety system settings, and limiting control settings; (2) limiting conditions for operation; 1

Topical Report SIR-94-080, Revision 1, Relaxation of Reactor Coolant Pump Flywheel Inspection Requirements, (ADAMS Accession No. ML18065B260)

Enclosure 2

(3) surveillance requirements; (4) design features; (5) administrative controls; (6) decommissioning; (7) initial notification; and (8) written reports. The regulation in 10 CFR 50.36(c)(5), Administrative controls, provide provisions relating to organization and management, procedures, recordkeeping, review and audit, and reporting necessary to assure the operation of the facility in a safe manner.

General Design Criterion (GDC) 4, Environmental and dynamic effects design bases, of Appendix A to 10 CFR Part 50 states, in part, that structures, systems, and components (SSCs) important to safety shall be designed to accommodate the effects of and to be compatible with the environmental conditions associated with normal operation, maintenance, testing, and postulated accidents, including loss-of-coolant accidents. GDC 4 further states, in part, that SSCs shall be appropriately protected against dynamic effects, including the effects of missiles, pipe whipping, and discharging fluids, that may result from equipment failures. The RCP flywheel is a large solid metallic disk that is part of the RCP motor. It is used to provide rotational inertia when the RCP motors are turned off to ensure slow decrease in reactor coolant flow. If the RCP flywheel fails during normal operation, it has sufficient kinetic energy to produce high-energy missiles that could damage SSCs important to safety in the reactor coolant system. Thus, structural integrity of the RCP flywheels must be maintained in order to meet the design criterion of GDC 4.

Regulatory Guide (RG) 1.14, Reactor Coolant Pump Flywheel Integrity, dated August 1975, describes a method acceptable to the NRC staff of implementing this requirement with regard to minimizing the potential for failures of the flywheels of reactor coolant pump motors in light-water-cooled power reactors.

3.0 TECHNICAL EVALUATION

3.1 Licensees Proposed Changes The licensee proposed to modify the St. Lucie Unit 2 RCP Flywheel Inspection Program requirements in the St. Lucie Unit 2 TS 6.8.4.o Reactor Coolant Pump Flywheel Inspection Program, to be consistent with the conclusions specified in the staffs SE of Topical Report SIR-94-080, Revision 1. The overall conclusion in Section 4 of the SE of Topical Report SIR-94-080, Revision 1 states, in part:

Licensees meeting (1) above should either conduct a qualified in-place UT

[ultrasonic testing] volumetric examination over the volume from the inner bore of the flywheel to the circle of one-half the outer radius or conduct a surface examination (MT and/or PT) of exposed surfaces defined by the volume of the disassembled flywheels once every 10 years.

Thus, the licensee proposed to modify St. Lucie Unit 2 TS 6.8.4.o to reflect volumetric examination of the RCP flywheel every 10 years in accordance with the above. This proposed modification would replace the RCP flywheel inspection specified in TS 6.8.4.o from the inspection schedule recommended in RG 1.14 to the inspection schedule recommended in the staffs SE of Topical Report SIR-94-080, Revision 1, as summarized above. In Section 4.0 of the SE of Topical Report SIR-94-080, Revision 1, the NRC staffs conclusion (1) lists specific plants, including St. Lucie Unit 2 that must verify the reference temperature (RTNDT) of the RCP flywheel and justify the use of the fracture toughness (KIC) curve in Appendix A of Section XI of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME Code).

The licensee verified the RTNDT of the St. Lucie Unit 2 RCP flywheel using the methodology

specified in NB-2331(a)(4) of the ASME Code,Section III, and justified the use of the KIC curve in Appendix A of the ASME Code,Section XI, by comparing the KIC value determined from Appendix A with values determined from empirical correlations of KIC with Charpy V-Notch (CVN) energy of the St. Lucie Unit 2 RCP flywheels.

The licensee stated that the St. Lucie Unit 2 RCP flywheels are made of American Society for Testing & Materials (ASTM) material ASTM-A 516-69 Grade 65, and that ASTM-A 516-69 Grade 65 exceeds the requirements of ASTM/ASME A-516 Grade 70. The NRC staff verified the licensees assertion that, as a result of a refurbishment effort between 2011 and 2017, each RCP motor and flywheel at St. Lucie Unit No. 1 were relocated to St. Lucie Unit 2.

In Section 3.3 Criterion 1: Reference Temperature - RTNDT of the enclosure to the licensees submittal, the licensee stated that it determined RTNDT per the procedures for pressure-retaining material in NB-2331(a)(4) of Section III of the ASME Code. NB-2331(a)(4) specifies that RTNDT may be determined from the temperature that represents 50 ft-lb and 35 mils lateral expansion from a full CVN curve. The licensee provided the CVN curves for transverse and longitudinal specimens of the St. Lucie Unit 2 RCP flywheel and determined a RTNDT value of -50°F for the flywheel material. The licensee stated that the CVN curves are from the Certified Mill Test Report (CMTR) for ASTM-A 516-69 Grade 65, dated June 1, 1971. Using the RTNDT value of

- 50°F, the licensee calculated a KIC value of 449.65 ksiin from the KIC equation in A-4000 of the ASME Code,Section XI, where T is the flywheel operating temperature of 100°F, as used in Topical Report SIR-94-080, Revision 1. The licensee also calculated KIC using empirical correlations of KIC with CVN and stated that the resulting values are of greater toughness than the lower bound ASME KIC vs. T-RTNDT curve.

The licensee estimated 2000 RCP start/stop cycles for the St. Lucie Unit 2 RCPs during the 60-year period of extended operation, which are bounded by the 4000 start/stop cycles analyzed in the fracture mechanics evaluation in Topical Report SIR-94-080, Revision 1. The licensee stated that the number of heatup and cooldown cycles is 500 based on the original 40-year design life (later confirmed by NRC staff to be applicable to a 60-year design life), with an additional one fill and vent activity per heatup and cooldown cycle, and each fill and vent activity comprising of three RCP start/stop cycles.

3.2 Staffs Evaluation The NRC staff reviewed the information contained in the licensees LAR and the supplemental information. The licensee proposed to modify the St. Lucie Unit 2, RCP Flywheel Inspection Program requirements in the St. Lucie Unit 2 TS 6.8.4.o to be consistent with the conclusions specified in the NRC staffs SE of Topical Report SIR-94-080, Revision 1. Topical Report SIR-94-080, Revision 1 contains fracture mechanics evaluations to justify inspection intervals for the RCP pump flywheel longer than those specified in RG 1.14. In Section 4.0 of the staffs SE of Topical Report SIR-94-080, Revision 1, staffs conclusion (1) specifies that licensees meeting the first condition stated in the SE should either conduct a volumetric examination through a qualified in-place [ultrasonic testing] UT examination or perform a surface examination. However, in the markup of St. Lucie Unit 2 TS 6.8.4.o in the licensees LAR, the licensee stated that the RCP flywheel be inspected 100% volumetric inspection and did not state the type of volumetric inspection to be a qualified in-place UT examination, as specified in the staffs SE of Topical Report SIR-94-080, Revision 1. In the April 30, 2020, supplement to the LAR, the licensee clarified that qualified in-place refers to calibrating the search probe on the component to be examined at a known location. The licensee stated that it uses qualified volumetric procedure NDE 5.15, Ultrasonic Examination of Reactor Coolant Pump Flywheels

for examining the RCP flywheels, which specifies calibrating the search probe on the RCP flywheel. The NRC staff finds that the UT procedure that the licensee is using to examine the RCP flywheel meets the intent of the meaning of qualified in-place in the staffs conclusion found in Section 4.0 of the staffs SE of Topical Report SIR-94-080, Revision 1. NRC staff made this determination because the UT procedure is considered to be a qualified procedure that uses search probes calibrated on the flywheel. Therefore, the staff finds the licensees clarification acceptable.

The NRC staff noted that the St. Lucie Plant, Unit No. 1 (St. Lucie Unit 1) RCP flywheel, that is made of ASTM-516-69 Grade 65, was relocated to St. Lucie Unit 2 between 2011 and 2017, as described in the enclosure to the licensees submittal. The staff verified that before 2011, the material of the St. Lucie Unit 1 RCP flywheel was, in fact, ASTM A-516-69 Grade 65 by confirming the material specification listed in a pre-2011 version of Table 5.5-9 of the St. Lucie Unit 1 Updated Final Safety Analysis Report (UFSAR). The NRC staff also noted that the -69 in the material name is from the older naming convention for SA-516 materials. The 1971 Edition of Section II Part A of the ASME Code, for example, indicates that SA-516 is identical to ASTM A 516-69. The newer naming convention does not have the -69. The 2013 edition of Section II Part A of the ASME Code, for example, indicates, also, that SA-516 is identical to ASTM A 516. The staff, therefore, determined that the current material of the St. Lucie Unit 2 RCP flywheel is ASTM A-516-69 Grade 65, as identified by the licensee. The NRC staff also noted that before the relocation, the St. Lucie Unit 2 RCP flywheel was made of ASTM A-543 Class 1 Type B, as indicated in the pre-2011 version of Table 5.4-1 of the St. Lucie Unit 2 UFSAR.

The NRC staff verified that the fracture toughness of ASTM A-516-69 Grade 65 exceeds the value of 90 ksiin (the minimum value analyzed in Topical Report SIR-94-080, Revision 1 for the two St. Lucie units), as described in the following four paragraphs.

The NRC staff noted that the licensee established RTNDT in accordance with NB-2331(a)(4) of Section III of the ASME Code, which is intended for pressure-retaining materials, even though the RCP flywheel is not a pressure-retaining component. The staff determined that this is acceptable since (1) the material that the St. Lucie Unit 2 RCP flywheel is made of is ASTM A-516-69 Grade 65, and according to the material specifications in Section II Part A of the ASME Code (2013 Edition), SA-516 materials (equivalent to ASTM A-516) are carbon steel plates intended primarily for service in welded pressure vessels; and (2) using pressure-retaining standards for non-pressure-retaining components is generally a conservative practice.

The NRC staff noted that the licensee used the CVN curve for the transverse data to determine the temperature at 50 ft-lb of absorbed energy, in accordance with NB-2331(a)(4), as the licensee described in the submittal. The staff noted that the licensee used the formula in NB-2331(a)(3) to calculate the value of RTNDT, which is specified as RTNDT = TCV - 60°F. TCV is the temperature at which the three test specimens of the St. Lucie Unit 2 RCP flywheel material exhibit a minimum of 50 ft-lb of absorbed energy and 35 mils lateral expansion. The staff reviewed the plot of CVN test data in the enclosure to the submittal and verified that the licensee calculated the RTNDT value of -50°F in accordance with NB-2331(a)(3) and NB-2331(a)(4) of Section III of the ASME Code.

Using the value of -50°F for RTNDT, the NRC staff verified the KIC value of 449.65 ksiin that the licensee calculated from the equation A-4000 of ASME Code,Section XI. The staff noted that the ASME Code,Section XI, uses a KIC equation with a maximum value of 200 ksiin. Despite

the difference between 449.65 ksiin and 200 ksiin, the staff noted that the 90 ksiin used in the fracture mechanics evaluation in Topical Report SIR-94-080, Revision 1 is substantially less than the licensees KIC values calculated from A-4000 of the ASME Code,Section XI, and from formulas using CVN test data specific to the St. Lucie Unit 2 RCP flywheel (discussed in the next paragraph) and is, therefore, conservative. Based on this, and the fact that the NRC staff have endorsed Topical Report SIR-94-080, Revision 1, the NRC staff determined that the licensees calculation of KIC is acceptable.

The NRC staff also verified the licensees calculation of KIC using the formulas the licensee provided in Section 3.5 of the enclosure to the submittal, which are based on empirical correlations (developed by Sailors and Corten as well as Roberts and Newton) of KIC with CVN.

While the NRC staff has not endorsed the use of these formulas for all applications, the staff has previously evaluated a licensees use of these formulas for a similar application. For example, in a February 1, 2002, SE for Millstone Power Station, Unit No. 2 (MPS2) (ADAMS Accession No. ML013370406), the NRC staff stated that the formulas were conservatively derived excluding the strain-rate effect, and that there was approximately an 18 percent additional margin of fracture toughness for the subject RCP flywheel relative to the Topical Report SIR-94-080, Revision 1, to account for uncertainties associated with using the formulas.

The staffs conclusion in the SE for MPS2, was that use of the formulas was adequate for the subject RCP flywheel because the RTNDT and KIC values provided for adequate resistance to fracture using a revised 10-year inspection interval. In addition, for that application, the staff evaluated a fracture toughness value of 90 ksiin, which is equivalent to the minimum fracture toughness value used in Topical Report SIR-94-080, Revision 1 for the St. Lucie Unit 2 RCP flywheels. The staff noted that the formula-based KIC values reported in the St. Lucie Unit 2 submittal were higher than those reported in the MPS2 application, which used approximately an 18 percent higher fracture toughness margin. Therefore, there is at least an 18 percent fracture toughness margin that exists relative to the St. Lucie Unit 2 RCP flywheels.

Accordingly, the NRC staff finds the use of the empirical formulas for the St. Lucie Unit 2 RCP flywheels acceptable.

The licensee presented a table of the resulting KIC values using the formulas discussed in Section 3.1 of this SE, which the NRC staff verified were correctly calculated. The licensee stated that the KIC values using the formulas are of greater toughness than the lower bound ASME KIC vs. T-RTNDT curve. The staff determined this conclusion to be inconsistent with the licensees calculation of KIC using equation A-4000 of ASME Code,Section XI, as discussed in the previous paragraph. The NRC staff noted that all of the KIC values using the empirical formulas were less than the ASME Code KIC values discussed in this SE. However, the staff also noted that the resulting formula-based KIC values were greater than the 90 ksiin used in the fracture mechanics evaluation in Topical Report SIR-94-080, Revision 1. In the supplements to the LAR, the licensee provided additional information regarding the ASME Code KIC calculations. The licensee conservatively used the temperatures of 72°F (room temperature) and 110°F for RTNDT, which were the temperatures at which the CVN values were taken for the formula-based KIC calculations. The licensee calculated a resulting ASME Code KIC value of 69.5 ksiin at T = 100°F and RTNDT = 72°F, and an ASME Code KIC value of 50 ksiin at T = 100°F and RTNDT = 110°F. The NRC staff verified that both calculations are correct and noted that the formula-based KIC values are greater than both the ASME Code KIC values and the 90 ksiin used in the fracture mechanics evaluation in Topical Report SIR-94-080, Revision 1.

The NRC staff confirmed that in Table 3.9-2, Transients Used in Design and Fatigue Analysis, of the St. Lucie Unit 2 UFSAR, the unit is designed for 500 heatup and cooldown cycles and that

500 cycles is acceptable for the license renewal period of 60 years. Thus, with the additional one fill and vent activity per heatup and cooldown cycle and each fill and vent activity comprising of three RCP start/stop cycles, the total number of RCP start/stop cycles is 500 +

(500 x 3) = 2000 RCP start/stop cycles. Therefore, the NRC staff finds that the fracture mechanics evaluation in Topical Report SIR-94-080, Revision 1 can be applied to the St. Lucie Unit 2 RCP flywheel for 60 years of operation since 2000 RCP start/stop cycles is less than the 4000 cycles evaluated in Topical Report SIR-94-080, Revision 1.

The NRC staff also noted that there have been no flaws in the St. Lucie Unit 2 RCP flywheels, as documented in the summary of a public meeting with the licensee, held on March 13, 2019 (ADAMS Accession No. ML19149A594). Specifically, staff noted in the public meeting summary that [t]he licensee stated that the RCP flywheels have been periodically inspected in accordance with applicable requirements, with no flaws noted.

Based on the above discussion, the NRC staff determined that the licensee has adequately addressed the staffs conclusion described in Section 4 of the SE of Topical Report SIR-94-080, Revision 1. The staff determined that the licensees proposed volumetric examination of the St. Lucie Unit 2 RCP flywheels, performed every 10 years, provides reasonable assurance of structural integrity of the RCP flywheels for the following reasons: (1) the fracture toughness value of the St. Lucie Unit 2 RCP flywheels is greater than the lowest fracture toughness value in the fracture mechanics evaluation in Topical Report SIR-94-080, Revision 1, (2) the number of start/stop cycles of the St. Lucie Unit 2 RCP for 60 years of operation is less than the number of RCP start/stop cycles used in the fracture mechanics evaluation in Topical Report SIR-94-080, Revision 1, and (3) the inspection of the RCP flywheels have reported no flaws to date.

3.3 Technical Conclusion The NRC staff reviewed the licensees LAR to change the inservice inspection requirements in TS 6.8.4.o for the RCP flywheel for the St. Lucie Unit 2 facility. Based on the evaluation in Section 3.2 of this SE, the staff concludes that the licensees proposed change meets the requirements of GDC 4 of Appendix A to 10 CFR Part 50 by providing adequate protection against cracking of the St. Lucie Unit 2 RCP flywheels and, thus, ensuring their structural integrity. The NRC staff also finds that the proposed change continues to meet 10 CFR 50.36(c)(5) by providing provisions necessary to assure operation of the facility in a safe manner. Therefore, the staff finds the licensees proposed change in the St. Lucie Unit 2 TS 6.8.4.o acceptable.

4.0 STATE CONSULTATION

In accordance with the Commission's regulations, the NRC staff notified the State of Florida official on September 14, 2020, of the proposed issuance of the amendment. The State official had no comments.

5.0 ENVIRONMENTAL CONSIDERATION

The amendment changes requirements with respect to the installation or use of facility components located within the restricted area, as defined in 10 CFR Part 20. The NRC staff has determined that the amendment involves no significant increase in the amounts, and no significant change in the types, of any effluents that may be released off-site, and that there is no significant increase in individual or cumulative occupational radiation exposure. The Commission has previously issued a proposed finding, which was published in the Federal

Register on March 24, 2020 (85 FR 16683), that the amendment involves no significant hazards consideration, and there has been no public comment on such finding. Accordingly, the amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9).

Pursuant to 10 CFR 51.22(b), no environmental impact statement or environmental assessment need be prepared in connection with the issuance of the amendment.

6.0 CONCLUSION

The Commission has concluded, based on the considerations discussed above, that: (1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, (2) there is reasonable assurance that such activities will be conducted in compliance with the Commissions regulations, and (3) the issuance of the amendment will not be inimical to the common defense and security or to the health and safety of the public.

Principal Contributor: D. Dijamco Date: November 18, 2020

ML20259A298 *by e-mail **by memorandum OFFICE DORL/LPL2-2/PM* DORL/LPL2-2/LA* DSS/STSB/BC* DNRL/NVIB/BC**

NAME NJordan BAbeywickrama VCusumano HGonzalez DATE 08/18/2020 09/17/2020 11/18/2020 07/17/2020 OFFICE OGC (NLO)* DORL/LPL2-2/BC* DORL/LPL2-2/PM*

NAME MWoods UShoop NJordan DATE 11/13/2020 11/18/2020 11/18/2020