ML23103A195

Cycle 26 Core Operating Limits Report Revision 0

ML23103A195
Person / Time
Site:	Sequoyah
Issue date:	04/13/2023
From:	Marshall T Tennessee Valley Authority
To:	Office of Nuclear Reactor Regulation, Document Control Desk
References
Download: ML23103A195 (1)

Text

Sequoyah Nuclear Plant, P.O. Box 2000, Soddy Daisy, Tennessee 37384 April 13, 2023 10 CFR 50.4 ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington, D.C. 20555-0001 Sequoyah Nuclear Plant, Unit 2 Renewed Facility Operating License No. DPR-79 NRC Docket No. 50-328

Subject:

SEQUOYAH UNIT 2 CYCLE 26 CORE OPERATING LIMITS REPORT REVISION 0 In accordance with Sequoyah Nuclear Plant (SQN) Unit 2 Technical Specification (TS) 5.6.3.d, enclosed is the Unit 2 Cycle 26 Core Operating Limits Report (COLR), Revision 0 that was issued on March 29, 2023.

There are no new regulatory commitments in this letter. If you have any questions, please contact Rick Medina, SQN Site Licensing Manager at (423) 843-8129.

Respectfully, Marshall, Digitally signed by Marshall, Thomas B.

Thomas B. Date: 2023.04.13 09:59:44

-04'00' Thomas Marshall Site Vice President Sequoyah Nuclear Plant

Enclosure:

Sequoyah Unit 2 Cycle 26 Core Operating Limits Report, Revision 0 cc (Enclosure):

NRC Regional Administrator - Region II NRC Senior Resident Inspector - SQN

ENCLOSURE SEQUOYAH UNIT 2 CYCLE 26 CORE OPERATING LIMITS REPORT REVISION 0

COLR FOR SEQUOYAH UNIT 2 CYCLE 26 1.0 CORE OPERATING LIMITS REPORT This Core Operating Limits Report (COLR) for Sequoyah Nuclear Plant Unit 2 has been prepared in accordance with the requirements of the Technical Specifications (TS) 5.6.3.

The Technical Specifications affected by this report are listed below:

TS COLR COLR Section Technical Specification COLR Parameter Section Page 2.1.1 Reactor Core Safety Limits Reactor Core Safety Limits 2.1 3 2.2.1 3 3.1.1 SHUTDOWN MARGIN (SDM) SDM 2.2.2 3 BOL MTC Limit 2.3.1 4 Moderator Temperature Coefficient EOL MTC Limit 2.3.1 4 3.1.3 (MTC) 300 ppm Surveillance Limit 2.3.2 4 60 ppm Surveillance Limit 2.3.3 4 3.1.4 Rod Group Alignment Limits SDM 2.2.3 3 Shutdown Bank Insertion Limits 2.4 4 3.1.5 Shutdown Bank Insertion Limits SDM 2.2.4 3 Control Bank Insertion Limits 2.5 4 3.1.6 Control Bank Insertion Limits SDM 2.2.5 3 PHYSICS TESTS Exceptions -

3.1.8 SDM 2.2.6 3 MODE 2 FQRTP 2.6.1 5 K(Z) 2.6.2 5 FQW(Z) 2.6.3 5 Heat Flux Hot Channel Factor [T(Z)]COLR 2.6.4 5 3.2.1 (FQ(Z)) Axy(Z) Factor 2.6.5 5 Rj Penalty Factor 2.6.6 5 Thermal Power Limits 2.6.7 6 UFQ 2.6.8 6 Nuclear Enthalpy Rise Hot Channel 3.2.2 FHN 2.7 6 Factor (FHN) 3.2.3 Axial Flux Difference (AFD) AFD Limits 2.8 6 Overtemperature T Trip Setpoints 2.9.1 7 Reactor Trip System (RTS) Overpower T Trip Setpoints 2.9.2 7 3.3.1 Instrumentation QTNL, QTPL, QTNS, and QTPS 2.9.3 7 QPNL, QPPL, QPNS, and QPPS 2.9.4 8 RCS Pressure, Temperature, and Pressurizer pressure 3.4.1 Flow Departure from Nucleate RCS average temperature 2.10 8 Boiling (DNB) Limits RCS flow 3.9.1 Boron Concentration Refueling Boron Concentration 2.11 8 CORE OPERATING LIMITS 5.6.3 Analytical Methods Table 1 13 REPORT (COLR)

Unit 2 Cycle 26 SEQUOYAH Page 2 of 19 Revision 0

COLR FOR SEQUOYAH UNIT 2 CYCLE 26 2.0 OPERATING LIMITS The cycle-specific parameter limits for the specifications listed in Section 1.0 are presented in the following subsections. These limits have been developed using the NRC approved methodologies specified in the Technical Specifications 5.6.3.

The following abbreviations are used in this section:

BOL -- Beginning of Cycle Life ARO -- All Rods Out HZP -- Hot Zero Thermal Power EOL -- End of Cycle Life RTP -- Rated Thermal Power RCS -- Reactor Coolant System RAOC -- Relaxed Axial Offset Control ROS -- RAOC Operating Space SFCP -- Surveillance Frequency Control Program 2.1 REACTOR CORE SAFETY LIMITS (Safety Limit 2.1.1)

In MODES 1 and 2, the combination of THERMAL POWER, Reactor Coolant System (RCS) highest loop average temperature, and pressurizer pressure shall not exceed the limits in Figure 1.

2.2 SHUTDOWN MARGIN (LCO 3.1.1, 3.1.4, 3.1.5, 3.1.6, 3.1.8) 2.2.1 For TS 3.1.1, SDM shall be 1.6% k/k in MODE 2 with keff < 1.0, MODE 3 and MODE 4.

2.2.2 For TS 3.1.1, SDM shall be 1.0% k/k in MODE 5.

2.2.3 For TS 3.1.4, SDM shall be 1.6% k/k in MODE 1 and MODE 2.

2.2.4 For TS 3.1.5, SDM shall be 1.6% k/k in MODE 1 and MODE 2.

2.2.5 For TS 3.1.6, SDM shall be 1.6% k/k in MODE 1 and MODE 2 with keff 1.0.

2.2.6 For TS 3.1.8, SDM shall be 1.6% k/k in MODE 2.

Unit 2 Cycle 26 SEQUOYAH Page 3 of 19 Revision 0

COLR FOR SEQUOYAH UNIT 2 CYCLE 26 2.3 MODERATOR TEMPERATURE COEFFICIENT - MTC (LCO 3.1.3) 2.3.1 The Moderator Temperature Coefficient (MTC) limits are:

The ARO/HZP - MTC shall be less positive than 0 k/k/°F (upper limit). With the BOL/ARO/HZP - MTC more positive than -3.913 x 10-5 k/k/°F (BOL MTC limit),

establish control rod withdrawal limits to ensure the MTC remains less positive than or equal to 0 k/k/°F (upper limit) for all times in core life.

The EOL/ARO/RTP-MTC shall be less negative than or equal to

-4.35 x 10-4 k/k/°F (lower limit).

2.3.2 The 300 ppm surveillance limit is:

The 300 ppm /ARO/RTP-MTC should be less negative than or equal to

-3.70 x 10-4 k/k/°F.

2.3.3 The 60 ppm surveillance limit is:

The measured 60 ppm /ARO/RTP-MTC should be less negative than or equal to

-4.10 x 10-4 k/k/°F.

2.4 SHUTDOWN BANK INSERTION LIMITS (LCO 3.1.5) 2.4.1 The shutdown banks shall be withdrawn to a position greater than or equal to 225 steps withdrawn.

2.5 CONTROL BANK INSERTION LIMITS (LCO 3.1.6) 2.5.1 The control banks are fully withdrawn or shall be limited in physical insertion as shown in Figure 2.

2.5.2 Each control bank shall be considered fully withdrawn from the core at greater than or equal to 225 steps.

2.5.3 The control banks shall be operated in sequence by withdrawal of Bank A, Bank B, Bank C, and Bank D. The control banks shall be sequenced in reverse order upon insertion.

2.5.4 Each control bank not fully withdrawn from the core shall be operated with the following overlap as a function of park position.

Park Position (steps) Bank Overlap (steps) Bank Difference Tip-to-Tip Separation (steps) 225 97 128 226 98 128 227 99 128 228 100 128 229 101 128 230 102 128 231 103 128 Unit 2 Cycle 26 SEQUOYAH Page 4 of 19 Revision 0

COLR FOR SEQUOYAH UNIT 2 CYCLE 26 2.6 HEAT FLUX HOT CHANNEL FACTOR - FQ(Z) (LCO 3.2.1)

() () > 0.5

() () 0.5

0.5 where

() = () U

=

2.6.1 = 2.62 2.6.2 K(Z) is provided in Figure 3.

2.6.3

() () > 0.5

() () 0.5

0.5 where

[()]

() = [ ()] () U > 0.5

[()]

() = [ ()] () U 0.5 0.5 and, [ ()] is the measured planar radial peaking factor.

() evaluations are not applicable for axial core regions, measured in percent of core height:

a. Lower core region, from 0 to 10% inclusive,

b. Upper core region, from 90 to 100% inclusive,

c. Grid plane regions, +/-2% inclusive, and

d. Core plane regions, within +/-2% of the bank demand positions of the control banks.

2.6.4

[()] values are provided in Tables 2 and 3 for RAOC operating space one (ROS1) and RAOC operating space two (ROS2).

Unit 2 Cycle 26 SEQUOYAH Page 5 of 19 Revision 0

COLR FOR SEQUOYAH UNIT 2 CYCLE 26 2.6.5 The () factors adjust the surveillance to the reference conditions assumed in generating the [()] factors. () may be assumed to equal 1.0 or may be determined for specific surveillance conditions using the approved methods listed in TS 5.6.3.

2.6.6 The penalty factors account for the potential decrease in transient FQ margin between surveillances. The factors for ROS1 and ROS2 are provided in Tables 4 and 5 respectively.

2.6.7 Table 6 provides the required limits on THERMAL POWER and the required AFD reductions for each ROS in the event that additional margin is required.

2.6.8 The uncertainty, UFQ, to be applied to measured FQ(Z) shall be calculated by the following:

UFQ = Uqu

• Ue where:

Uqu = Base FQ measurement uncertainty = 1.05 when PDMS is inoperable (Uqu is defined by PDMS and cannot be less than 1.05 when OPERABLE)

Ue = Engineering uncertainty factor = 1.03 2.7 NUCLEAR ENTHALPY RISE HOT CHANNEL FACTOR - FHN (LCO 3.2.2)

FHN

• UH FHRTP * ( 1 + PFH * ( 1-P))

where P = Thermal Power / Rated Thermal Power FHRTP = 1.70 for RFA-2 fuel, and 1.61 for HTP fuel PFH = 0.3 The uncertainty, UH, to be applied to measured FHN shall be 1.04 when PDMS is inoperable (UH is defined by PDMS and cannot be less than 1.04 when OPERABLE).

2.8 AXIAL FLUX DIFFERENCE - AFD (LCO 3.2.3)

The AFD limits for Cycle 26 are provided in Figure 4.

Unit 2 Cycle 26 SEQUOYAH Page 6 of 19 Revision 0

COLR FOR SEQUOYAH UNIT 2 CYCLE 26 2.9 REACTOR TRIP SYSTEM (RTS) INSTRUMENTATION (LCO 3.3.1) 2.9.1 Overtemperature T Trip Setpoints Parameter Value Overtemperature T reactor trip setpoint K1 1.15 Overtemperature T reactor trip setpoint Tavg coefficient K2 0.015/°F Overtemperature T reactor trip setpoint pressure coefficient K3 = 0.0008/psig Nominal Tavg at RTP T' 578.2°F Nominal RCS operating pressure P' = 2235 psig Measured RCS T lead/lag time constants 4 5 sec 5 3 sec Measured RCS average temperature lead/lag time constants 1 33 sec 2 4 sec 2.9.2 Overpower T Trip Setpoints Parameter Value Overpower T reactor trip setpoint K4 1.087 Overpower T reactor trip setpoint Tavg rate/lag coefficient K5 0.02/°F for increasing Tavg 0/°F for decreasing Tavg Overpower T reactor trip setpoint Tavg heatup coefficient K6 0.0011/°F when T > T 0/°F when T T Nominal Tavg at RTP T" 578.2°F Measured RCS T lead/lag time constants 4 5 sec 5 3 sec Measured RCS average temperature rate/lag time constant 3 10 sec 2.9.3 Trip Reset Term [f1(I)] for Overtemperature T Trip The following parameters are required to specify the power level-dependent f1(I) trip reset term limits for TS Table 3.3.1-1 (function 6), Overtemperature T trip function:

2.9.3.1 QTNL = -20%

where QTNL = the maximum negative I setpoint at RATED THERMAL POWER at which the trip setpoint is not reduced by the axial power distribution.

2.9.3.2 QTPL = +5%

where QTPL = the maximum positive I setpoint at RATED THERMAL POWER at which the trip setpoint is not reduced by the axial power distribution.

2.9.3.3 QTNS = 2.50%

where QTNS = the percent reduction in Overtemperature T trip setpoint for each percent that the magnitude of I exceeds its negative limit at RATED THERMAL POWER (QTNL).

2.9.3.4 QTPS = 1.40%

where QTPS = the percent reduction in Overtemperature T trip setpoint for each percent that the magnitude of I exceeds its positive limit at RATED THERMAL POWER (QTPL).

Unit 2 Cycle 26 SEQUOYAH Page 7 of 19 Revision 0

COLR FOR SEQUOYAH UNIT 2 CYCLE 26 2.9.4 Trip Reset Term [f2(I)] for Overpower T Trip The following parameters are required to specify the power level-dependent f2(I) trip reset term limits for TS Table 3.3.1-1 (function 7), Overpower T trip function:

2.9.4.1 QPNL = 0%

where QPNL = the maximum negative I setpoint at RATED THERMAL POWER at which the trip setpoint is not reduced by the axial power distribution.

2.9.4.2 QPPL = 0%

where QPPL = the maximum positive I setpoint at RATED THERMAL POWER at which the trip setpoint is not reduced by the axial power distribution.

2.9.4.3 QPNS = 0%

where QPNS = the percent reduction in Overpower T trip setpoint for each percent that the magnitude of I exceeds its negative limit at RATED THERMAL POWER (QPNL).

2.9.4.4 QPPS = 0%

where QPPS = the percent reduction in Overpower T trip setpoint for each percent that the magnitude of I exceeds its positive limit at RATED THERMAL POWER (QPPL).

2.10 RCS PRESSURE, TEMPERATURE, AND FLOW DEPARTURE FROM NUCLEATE BOILING (DNB) LIMITS (LCO 3.4.1)

Parameter Indicated Value Pressurizer pressure 2220 psia RCS average temperature 583F RCS flow 378,400 gpm 2.11 REFUELING BORON CONCENTRATION (LCO 3.9.1)

The refueling boron concentration shall be 2000 ppm.

Unit 2 Cycle 26 SEQUOYAH Page 8 of 19 Revision 0

COLR FOR SEQUOYAH UNIT 2 CYCLE 26 Figure 1 Reactor Core Safety Limits RCS T-avg Versus Rated Thermal Power Unit 2 Cycle 26 SEQUOYAH Page 9 of 19 Revision 0

COLR FOR SEQUOYAH UNIT 2 CYCLE 26 Figure 2 Control Bank Insertion Limits Versus Rated Thermal Power Four Loop Operation Note: the above control bank insertion limits are applicable to both ROS1 and ROS2.

• Fully withdrawn region shall be the condition where shutdown and control banks are at a position within the interval of 225 and 231 steps withdrawn.

Unit 2 Cycle 26 SEQUOYAH Page 10 of 19 Revision 0

COLR FOR SEQUOYAH UNIT 2 CYCLE 26 1.2 1.1 1

0.9 0.8 Normalized FQ

• Power 0.7 0.6 Core Height K(Z) 0.000 1.000 6.000 1.000 0.5 12.000 1.000 0.4 0.3 0.2 0.1 0

0 1 2 3 4 5 6 7 8 9 10 11 12 Core Height (feet)

Figure 3 K(Z) - Normalized FQ(Z) as a Function of Core Height Unit 2 Cycle 26 SEQUOYAH Page 11 of 19 Revision 0

COLR FOR SEQUOYAH UNIT 2 CYCLE 26 110 100 Unacceptable Unacceptable 90 ROS 1 RA-1 80 ROS 2 RA-2 70 Acceptable

% of Rated Thermal Power 60 50 40 30 20 10 0

-40 -35 -30 -25 -20 -15 -10 -5 0 5 10 15 20 25 30 Axial Flux Difference (I %)

Figure 4 Axial Flux Difference Acceptable Operation Limits as a function of Rated Thermal Power (RAOC)

Unit 2 Cycle 26 SEQUOYAH Page 12 of 19 Revision 0

COLR FOR SEQUOYAH UNIT 2 CYCLE 26 Table 1 COLR Methodology Topical Reports

1. WCAP-8745-P-A, Design Bases for the Thermal Overpower T and Thermal Overtemperature T Trip Functions, September 1986.

(methodology for OTT and OPT Reactor Trip System setpoints in TS 3.3.1)

2. WCAP-9272-P-A, Westinghouse Reload Safety Evaluation Methodology, July 1985.

(methodology for Shutdown Margin, Moderator Temperature Coefficient, Shutdown Bank Insertion Limit, Control Bank Insertion Limits, Axial Flux Difference, Heat Flux Hot Channel Factor, Nuclear Enthalpy Rise Hot Channel Factor, DNB Limits, Refueling Pool Boron Concentration)

3. WCAP-10216-P-A, Revision 1A, Relaxation of Constant Axial Offset Control - FQ Surveillance Technical Specification, February 1994.

(methodology for Axial Flux Difference limits with Relaxed Axial Offset Control and Heat Flux Hot Channel Factor (W(z)) Surveillance Requirements for FQ)

4. WCAP-10444-P-A, Reference Core Report VANTAGE 5 Fuel Assembly, September 1985.

(methodology for Axial Flux Difference and Heat Flux Hot Channel Factor Limits)

5. WCAP-10444-P-A Addendum 2-A, VANTAGE 5H Fuel Assembly, February 1989.

(methodology for Axial Flux Difference and Heat Flux Hot Channel Factor Limits)

6. WCAP-10965-P-A, ANC: A Westinghouse Advanced Nodal Computer Code, September 1986.

(methodology for Shutdown Margin, Moderator Temperature Coefficient, Shutdown Bank Insertion Limit, Control Bank Insertion Limits, Axial Flux Difference, Heat Flux Hot Channel Factor, Nuclear Enthalpy Rise Hot Channel Factor, Refueling Pool Boron Concentration)

7. WCAP-10965-P-A, Addendum 2-A, Revision 0, Qualification of the New Pin Power Recovery Methodology, September 2010.

(methodology for Shutdown Margin, Moderator Temperature Coefficient, Shutdown Bank Insertion Limit, Control Bank Insertion Limits, Heat Flux Hot Channel Factor, Nuclear Enthalpy Rise Hot Channel Factor, Axial Flux Difference, TS 3.4.1 DNB Limits, Refueling Pool Boron Concentration)

8. WCAP-11397-P-A, Revised Thermal Design Procedure, April 1989.

(methodology for Reactor Core Safety Limits, Nuclear Enthalpy Rise Hot Channel Factor, TS 3.4.1 DNB Limits)

9. WCAP-12610-P-A, VANTAGE+ Fuel Assembly Reference Core Report, April 1995.

(methodology for Axial Flux Difference and Heat Flux Hot Channel Factor Limits)

10. WCAP-12610-P-A & CENPD-404-P-A, Addendum 1-A, Optimized ZIRLOTM, July 2006.

(methodology for Axial Flux Difference and Heat Flux Hot Channel Factor Limits)

11. WCAP-14565-P-A, VIPRE-01 Modeling and Qualification for Pressurized Water Reactor Non-LOCA Thermal-Hydraulic Safety Analysis, October 1999.

(methodology for Reactor Core Safety Limits, Nuclear Enthalpy Rise Hot Channel Factor, and TS 3.4.1 DNB Limits)

Unit 2 Cycle 26 SEQUOYAH Page 13 of 19 Revision 0

COLR FOR SEQUOYAH UNIT 2 CYCLE 26

12. WCAP-14565-P-A, Addendum 1-A, Revision 0, Addendum 1 to WCAP 14565-P-A Qualification of ABB-NV Critical Heat Flux Correlations with VIPRE-01 Code, August 2004.

(methodology for Axial Flux Difference)

13. WCAP-14565-P-A, Addendum 2-P-A, Revision 0, Addendum 2 to WCAP-14565-P-A Extended Application of ABB-NV Correlation and Modified ABB-NV Correlation WLOP for PWR Low Pressure Applications, April 2008.

(methodology for TS 3.4.1 DNB Limits)

14. WCAP-15025-P-A, Modified WRB-2 Correlation, WRB-2M, for Predicting Critical Heat Flux in 17x17 Rod Bundles with Modified LPD Mixing Vane Grids, April 1999.

(methodology for Reactor Core Safety Limits and Nuclear Enthalpy Rise Hot Channel Factor)

15. WCAP-16045-P-A, Qualification of the Two-Dimensional Transport Code PARAGON, August 2004.

(methodology for Shutdown Margin, Moderator Temperature Coefficient, Shutdown Bank Insertion Limit, Control Bank Insertion Limits, Heat Flux Hot Channel Factor, Nuclear Enthalpy Rise Hot Channel Factor, Axial Flux Difference, TS 3.4.1 DNB Limits, Refueling Pool Boron Concentration)

16. WCAP-16045-P-A, Addendum 1-A, Qualification of the NEXUS Nuclear Data Methodology, August 2007.

(methodology for Moderator Temperature Coefficient)

17. WCAP-16996-P-A, Revision 1, Realistic LOCA Evaluation Methodology Applied to the Full Spectrum of Break Sizes (FULL SPECTRUM LOCA Methodology), November 2016.

(methodology for FQ and FNH limits)

18. WCAP-17661-P-A, Revision 1, "Improved RAOC and CAOC FQ Surveillance Technical Specifications," February 2019.

(methodology for control bank insertion limits, FQ limits, and AFD limits)

Unit 2 Cycle 26 SEQUOYAH Page 14 of 19 Revision 0

COLR FOR SEQUOYAH UNIT 2 CYCLE 26 Table 2

[T(Z)]COLR Factors for ROS1 Elevation 150 4000 6000 10000 14000 18000 Point (ft) MWD/MTU MWD/MTU MWD/MTU MWD/MTU MWD/MTU MWD/MTU 1 12.2067 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 2 12.0033 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 3 11.7998 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 4 11.5964 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 5 11.3929 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 6 11.1895 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 7 10.9860 1.3892 1.0490 1.0184 1.0934 1.2470 1.2653 8 10.7826 1.3530 1.0621 1.0406 1.1179 1.2668 1.2844 9 10.5791 1.3913 1.1208 1.1114 1.2008 1.3390 1.3383 10 10.3757 1.3609 1.1372 1.1412 1.2224 1.3444 1.3314 11 10.1723 1.3651 1.1810 1.1866 1.2494 1.3524 1.3348 12 9.9688 1.2768 1.2090 1.2146 1.2480 1.3121 1.2800 13 9.7654 1.3416 1.2253 1.2478 1.2875 1.3221 1.3162 14 9.5619 1.2238 1.2384 1.2422 1.2652 1.2871 1.2866 15 9.3585 1.2094 1.2159 1.2420 1.2716 1.2846 1.2836 16 9.1550 1.1609 1.2097 1.2142 1.2374 1.2460 1.2511 17 8.9516 1.2221 1.2707 1.2698 1.2753 1.2664 1.2629 18 8.7481 1.2421 1.3104 1.3021 1.3152 1.2847 1.2702 19 8.5447 1.2727 1.3319 1.3357 1.3264 1.2883 1.2668 20 8.3412 1.2856 1.3802 1.3747 1.3693 1.3145 1.2948 21 8.1378 1.3084 1.4049 1.3997 1.3851 1.3205 1.3019 22 7.9344 1.2924 1.3749 1.3714 1.3499 1.2801 1.2665 23 7.7309 1.3005 1.3883 1.3852 1.3556 1.2810 1.2693 24 7.5275 1.2662 1.3695 1.3672 1.3336 1.2612 1.2523 25 7.3240 1.2641 1.3554 1.3529 1.3133 1.2421 1.2355 26 7.1206 1.3143 1.4079 1.4006 1.3495 1.2725 1.2631 27 6.9171 1.2995 1.3989 1.3878 1.3322 1.2562 1.2473 28 6.7137 1.3192 1.4269 1.4107 1.3475 1.2705 1.2614 29 6.5102 1.2977 1.3943 1.3820 1.3113 1.2332 1.2364 30 6.3068 1.3098 1.4255 1.4031 1.3291 1.2552 1.2478 31 6.1034 1.2816 1.3862 1.3686 1.2888 1.2196 1.2157 32 5.8999 1.2586 1.3737 1.3591 1.2727 1.2076 1.2059 33 5.6965 1.2196 1.3313 1.3174 1.2257 1.1652 1.1717 34 5.4930 1.2521 1.3634 1.3464 1.2425 1.1812 1.1865 35 5.2896 1.2952 1.4110 1.3914 1.2825 1.2172 1.2162 36 5.0861 1.2967 1.4124 1.3948 1.2848 1.2229 1.2170 37 4.8827 1.2903 1.4055 1.3902 1.2838 1.2235 1.2128 38 4.6792 1.2935 1.4063 1.3933 1.2911 1.2316 1.2146 39 4.4758 1.3009 1.4094 1.3993 1.3076 1.2433 1.2237 40 4.2723 1.2929 1.3961 1.3896 1.3012 1.2450 1.2230 41 4.0689 1.2518 1.3484 1.3440 1.2718 1.2216 1.2010 42 3.8655 1.2399 1.3294 1.3260 1.2679 1.2208 1.1996 43 3.6620 1.2884 1.3754 1.3683 1.3194 1.2707 1.2412 44 3.4586 1.3083 1.3780 1.3736 1.3361 1.2928 1.2603 45 3.2551 1.3029 1.3564 1.3551 1.3367 1.2986 1.2647 46 3.0517 1.3033 1.3449 1.3485 1.3439 1.3151 1.2833 47 2.8482 1.3043 1.3411 1.3475 1.3600 1.3424 1.3147 48 2.6448 1.3052 1.3294 1.3399 1.3704 1.3666 1.3446 49 2.4413 1.3199 1.3313 1.3414 1.3930 1.4042 1.3808 50 2.2379 1.3036 1.2956 1.3042 1.3788 1.4094 1.3893 51 2.0345 1.3055 1.2748 1.2924 1.3774 1.4282 1.4206 52 1.8310 1.3847 1.2886 1.2952 1.4072 1.4761 1.4726 53 1.6276 1.3414 1.2585 1.2643 1.3908 1.4803 1.4901 54 1.4241 1.3199 1.2078 1.2188 1.3500 1.4604 1.4875 55 1.2207 1.2907 1.1472 1.1609 1.2916 1.4190 1.4642 56 1.0172 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 57 0.8138 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 58 0.6103 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 59 0.4069 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 60 0.2034 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 61 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 Unit 2 Cycle 26 SEQUOYAH Page 15 of 19 Revision 0

COLR FOR SEQUOYAH UNIT 2 CYCLE 26 Table 3

[T(Z)]COLR Factors for ROS2 Elevation 150 4000 6000 10000 14000 18000 Point (ft) MWD/MTU MWD/MTU MWD/MTU MWD/MTU MWD/MTU MWD/MTU 1 12.2067 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 2 12.0033 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 3 11.7998 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 4 11.5964 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 5 11.3929 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 6 11.1895 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 7 10.9860 1.3811 1.0099 1.0009 1.0738 1.2259 1.2629 8 10.7826 1.3536 1.0291 1.0326 1.1121 1.2652 1.2817 9 10.5791 1.3911 1.1058 1.1114 1.1916 1.3350 1.3364 10 10.3757 1.3609 1.1280 1.1412 1.2033 1.3321 1.3316 11 10.1723 1.3651 1.1706 1.1866 1.2284 1.3384 1.3337 12 9.9688 1.2768 1.1894 1.2146 1.2477 1.3120 1.2800 13 9.7654 1.3412 1.2253 1.2478 1.2673 1.3092 1.2959 14 9.5619 1.2227 1.2116 1.2422 1.2649 1.2778 1.2686 15 9.3585 1.1963 1.2117 1.2420 1.2534 1.2746 1.2577 16 9.1550 1.1614 1.2097 1.2142 1.2200 1.2430 1.2250 17 8.9516 1.2221 1.2610 1.2698 1.2751 1.2662 1.2528 18 8.7481 1.2421 1.3104 1.3021 1.3018 1.2847 1.2553 19 8.5447 1.2727 1.3173 1.3357 1.3264 1.2883 1.2668 20 8.3412 1.2849 1.3802 1.3747 1.3566 1.3145 1.2917 21 8.1378 1.3034 1.4049 1.3997 1.3730 1.3205 1.3016 22 7.9344 1.2924 1.3749 1.3714 1.3388 1.2801 1.2665 23 7.7309 1.3005 1.3883 1.3852 1.3453 1.2792 1.2693 24 7.5275 1.2525 1.3695 1.3672 1.3242 1.2562 1.2523 25 7.3240 1.2641 1.3554 1.3529 1.3049 1.2343 1.2355 26 7.1206 1.3143 1.4079 1.4006 1.3418 1.2615 1.2631 27 6.9171 1.2995 1.3989 1.3878 1.3255 1.2446 1.2473 28 6.7137 1.3192 1.4269 1.4107 1.3418 1.2603 1.2614 29 6.5102 1.2977 1.3943 1.3821 1.3113 1.2332 1.2364 30 6.3068 1.3029 1.4255 1.4005 1.3256 1.2485 1.2458 31 6.1034 1.2815 1.3862 1.3649 1.2865 1.2150 1.2114 32 5.8999 1.2575 1.3738 1.3573 1.2717 1.2047 1.1996 33 5.6965 1.2198 1.3308 1.3171 1.2252 1.1648 1.1657 34 5.4930 1.2480 1.3584 1.3421 1.2426 1.1798 1.1791 35 5.2896 1.2903 1.4007 1.3806 1.2750 1.2102 1.2059 36 5.0861 1.2889 1.3969 1.3742 1.2746 1.2055 1.2042 37 4.8827 1.2793 1.3836 1.3606 1.2685 1.2020 1.1975 38 4.6792 1.2780 1.3786 1.3576 1.2703 1.2074 1.1970 39 4.4758 1.2786 1.3792 1.3647 1.2760 1.2205 1.1991 40 4.2723 1.2640 1.3643 1.3450 1.2699 1.2130 1.1921 41 4.0689 1.2176 1.3132 1.2967 1.2349 1.1727 1.1641 42 3.8655 1.2040 1.2899 1.2768 1.2274 1.1784 1.1590 43 3.6620 1.2464 1.3260 1.3165 1.2754 1.2276 1.2010 44 3.4586 1.2575 1.3308 1.3224 1.2918 1.2413 1.2130 45 3.2551 1.2425 1.3093 1.3039 1.2904 1.2402 1.2160 46 3.0517 1.2477 1.2916 1.2906 1.2929 1.2475 1.2282 47 2.8482 1.2611 1.2839 1.2858 1.2924 1.2684 1.2530 48 2.6448 1.2623 1.2729 1.2746 1.2925 1.2847 1.2766 49 2.4413 1.2757 1.2737 1.2742 1.3125 1.3155 1.3129 50 2.2379 1.2592 1.2390 1.2384 1.2966 1.3173 1.3243 51 2.0345 1.2601 1.2185 1.2241 1.2931 1.3318 1.3496 52 1.8310 1.3620 1.2310 1.2254 1.3191 1.3737 1.4006 53 1.6276 1.2929 1.2017 1.1950 1.3022 1.3752 1.4159 54 1.4241 1.2715 1.1528 1.1509 1.2626 1.3546 1.4121 55 1.2207 1.2425 1.0944 1.0952 1.2068 1.3146 1.3888 56 1.0172 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 57 0.8138 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 58 0.6103 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 59 0.4069 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 60 0.2034 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 61 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 Unit 2 Cycle 26 SEQUOYAH Page 16 of 19 Revision 0

COLR FOR SEQUOYAH UNIT 2 CYCLE 26 Table 4 Rj Margin Decrease Factors for ROS1 Cycle Burnup Cycle Burnup Cycle Burnup (MWD/MTU) Rj (MWD/MTU) Rj (MWD/MTU) Rj 150 1.0170 7767 1.0071 15385 1.0094 340 1.0215 7958 1.0065 15575 1.0093 531 1.0254 8148 1.0008 15766 1.0094 721 1.0286 8339 1.0013 15956 1.0094 912 1.0308 8529 1.0126 16146 1.0093 1102 1.0317 8720 1.0197 16337 1.0091 1293 1.0311 8910 1.0233 16527 1.0089 1483 1.0305 9100 1.0240 16718 1.0089 1673 1.0316 9291 1.0247 16908 1.0091 1864 1.0301 9481 1.0256 17099 1.0092 2054 1.0275 9672 1.0268 17289 1.0094 2245 1.0250 9862 1.0226 17480 1.0095 2435 1.0218 10053 1.0158 17670 1.0097 2626 1.0178 10243 1.0147 17860 1.0099 2816 1.0135 10433 1.0136 18051 1.0099 3007 1.0099 10624 1.0151 18241 1.0097 3197 1.0081 10814 1.0141 18432 1.0094 3387 1.0083 11005 1.0130 18622 1.0090 3578 1.0088 11195 1.0120 18813 1.0092 3768 1.0108 11386 1.0109 19003 1.0095 3959 1.0131 11576 1.0103 19193 1.0099 4149 1.0154 11766 1.0099 19384 1.0103 4340 1.0166 11957 1.0096 19574 1.0108 4530 1.0168 12147 1.0071 19765 1.0112 4720 1.0162 12338 1.0068 19955 1.0112 4911 1.0147 12528 1.0065 20146 1.0113 5101 1.0143 12719 1.0063 20336 1.0119 5292 1.0117 12909 1.0065 20526 1.0124 5482 1.0091 13100 1.0069 20717 1.0133 5673 1.0066 13290 1.0073 5863 1.0045 13480 1.0078 6053 1.0063 13671 1.0082 6244 1.0079 13861 1.0087 6434 1.0070 14052 1.0091 6625 1.0115 14242 1.0096 6815 1.0107 14433 1.0097 7006 1.0099 14623 1.0096 7196 1.0091 14813 1.0095 7386 1.0083 15004 1.0095 7577 1.0076 15194 1.0094 Values may be interpolated to the surveillance cycle burnup.

Unit 2 Cycle 26 SEQUOYAH Page 17 of 19 Revision 0

COLR FOR SEQUOYAH UNIT 2 CYCLE 26 Table 5 Rj Margin Decrease Factors for ROS2 Cycle Burnup Cycle Burnup Cycle Burnup (MWD/MTU) Rj (MWD/MTU) Rj (MWD/MTU) Rj 150 1.0170 7767 1.0016 15385 1.0046 340 1.0215 7958 1.0015 15575 1.0045 531 1.0254 8148 1.0000 15766 1.0043 721 1.0286 8339 1.0001 15956 1.0041 912 1.0308 8529 1.0118 16146 1.0037 1102 1.0317 8720 1.0192 16337 1.0033 1293 1.0329 8910 1.0232 16527 1.0029 1483 1.0368 9100 1.0242 16718 1.0029 1673 1.0375 9291 1.0251 16908 1.0048 1864 1.0365 9481 1.0262 17099 1.0088 2054 1.0338 9672 1.0274 17289 1.0097 2245 1.0294 9862 1.0227 17480 1.0099 2435 1.0259 10053 1.0111 17670 1.0101 2626 1.0252 10243 1.0039 17860 1.0103 2816 1.0238 10433 1.0004 18051 1.0104 3007 1.0219 10624 1.0000 18241 1.0102 3197 1.0197 10814 1.0000 18432 1.0099 3387 1.0176 11005 1.0007 18622 1.0096 3578 1.0148 11195 1.0025 18813 1.0092 3768 1.0125 11386 1.0044 19003 1.0089 3959 1.0131 11576 1.0063 19193 1.0087 4149 1.0154 11766 1.0028 19384 1.0089 4340 1.0166 11957 1.0022 19574 1.0094 4530 1.0168 12147 1.0171 19765 1.0099 4720 1.0162 12338 1.0161 19955 1.0105 4911 1.0147 12528 1.0142 20146 1.0111 5101 1.0143 12719 1.0122 20336 1.0118 5292 1.0117 12909 1.0101 20526 1.0121 5482 1.0091 13100 1.0079 20717 1.0124 5673 1.0069 13290 1.0060 5863 1.0076 13480 1.0043 6053 1.0067 13671 1.0043 6244 1.0056 13861 1.0062 6434 1.0044 14052 1.0060 6625 1.0048 14242 1.0057 6815 1.0038 14433 1.0055 7006 1.0031 14623 1.0052 7196 1.0025 14813 1.0050 7386 1.0021 15004 1.0048 7577 1.0018 15194 1.0047 Values may be interpolated to the surveillance cycle burnup.

Unit 2 Cycle 26 SEQUOYAH Page 18 of 19 Revision 0

COLR FOR SEQUOYAH UNIT 2 CYCLE 26 Table 6 Required Thermal Power Limits and AFD Reductions Required Required FQW(Z) THERMAL RAOC Operating Margin POWER Limit Required AFD Space Improvement (%) (%RTP) Reduction 4.4 90 See Figure 4 RA-1 ROS1

> 4.4 < 50 N/A 3.0 90 See Figure 4 RA-2 ROS2

> 3.0 < 50 N/A Unit 2 Cycle 26 SEQUOYAH Page 19 of 19 Revision 0