NL-25-0177, Cycle 31 Core Operating Limits Report

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Cycle 31 Core Operating Limits Report
ML25128A190
Person / Time
Site: Farley Southern Nuclear icon.png
Issue date: 05/08/2025
From: Coleman J
Southern Nuclear Operating Co
To:
Office of Nuclear Reactor Regulation, Document Control Desk
References
NL-25-0177
Download: ML25128A190 (1)
v • d • e


Text

Regulatory Affairs 3535 Colonnade Parkway Birmingham, AL 35243 205 992 5000 May 8, 2025 Docket No.:

50-364 NL-25-0177 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D. C. 20555-0001 Joseph M. Farley Nuclear Plant - Unit 2 Cycle 31 Core Operating Limits Report Ladies and Gentlemen:

In accordance with Technical Specification 5.6.5.d, Southern Nuclear Operating Company (SNC) submits the enclosed Core Operating Limits Report (COLR) for the Joseph M.

Farley Nuclear Plant (FNP) - Unit 2 Cycle 31 Version 1.

This letter contains no NRC commitments. If you have any questions, please contact Ryan Joyce at 205.992.6468.

Respectfully submitted, Jamie Coleman Regulatory Affairs Director JC/was/cbg

Enclosure:

Core Operating Limits Report for FNP Unit 2 Cycle 31 Version 1 cc: Regional Administrator, Region ll NRR Project Manager - Farley Nuclear Plant Senior Resident Inspector - Farley Nuclear Plant RTYPE: CFA04.054

Joseph M. Farley Nuclear Plant - Unit 2 Cycle 31 Core Operating Limits Report Enclosure Core Operating Limits Report for FNP Unit 2 Cycle 31 Version 1

Joseph M. Farley Nuclear Plant Core Operating Limits Report Unit 2 - Cycle 31 Version 1 January 2025

CORE OPERATING LIMITS REPORT, FNP UNIT 2 CYCLE 31 January 2025 Page 1 of 20 1.0 CORE OPERATING LIMITS REPORT This Core Operating Limits Report (COLR) for FNP UNIT 2 CYCLE 31 has been prepared in accordance with the requirements of Technical Specification 5.6.5.

The Technical Requirement affected by this report is listed below:

13.1.1 SHUTDOWN MARGIN - MODES 1 and 2 (with keff t1)

The Technical Specifications affected by this report are listed below:

2.1.1 Reactor Core Safety Limits for THERMAL POWER 3.1.1 SHUTDOWN MARGIN - MODES 2 (with keff < 1), 3, 4 and 5 3.1.3 Moderator Temperature Coefficient 3.1.5 Shutdown Bank Insertion Limits 3.1.6 Control Bank Insertion Limits 3.2.1 Heat Flux Hot Channel Factor -

3.2.2 Nuclear Enthalpy Rise Hot Channel Factor -



3.2.3 Axial Flux Difference 3.3.1 Reactor Trip System Instrumentation Overtemperature 'T (OT'T) and Overpower 'T (OP'T) Setpoint Parameter Values for Table 3.3.1-1 3.4.1 RCS DNB Parameters for Pressurizer Pressure, RCS Average Temperature, and RCS Total Flow Rate 3.9.1 Boron Concentration

CORE OPERATING LIMITS REPORT, FNP UNIT 2 CYCLE 31 January 2025 Page 2 of 20 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 NRC-approved methodologies as specified in Technical Specification 5.6.5.

2.1 SHUTDOWN MARGIN - MODES 1 and 2 (with keff t1.0) (Technical Requirement 13.1.1) 2.1.1 The SHUTDOWN MARGIN shall be greater than or equal to 1.77 percent 'k/k.

2.2 SHUTDOWN MARGIN - MODES 2 (with keff < 1.0), 3, 4 and 5 (Specification 3.1.1) 2.2.1 Modes 2 (keff < 1.0), 3 and 4 - The SHUTDOWN MARGIN shall be greater than or equal to 1.77 percent 'k/k.

2.2.2 Mode 5 - The SHUTDOWN MARGIN shall be greater than or equal to 1.0 percent 'k/k.

CORE OPERATING LIMITS REPORT, FNP UNIT 2 CYCLE 31 January 2025 Page 3 of 20 2.3 Moderator Temperature Coefficient (Specification 3.1.3) 2.3.1 The Moderator Temperature Coefficient (MTC) limits are:

The BOL/ARO-MTC shall be less than or equal to +0.7 x 10-4 'k/k/qF for power levels up to 70 percent RTP with a linear ramp to 0 'k/k/qF at 100 percent RTP.

The EOL/ARO/RTP-MTC shall be less negative than -4.3 x 10-4 'k/k/qF.

2.3.2 The MTC Surveillance limits are:

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

-3.65 x 10-4 'k/k/qF.

The revised predicted near-EOL 300 ppm MTC shall be calculated using Figure 5 and the following algorithm:

Revised Predicted MTC = Predicted MTC* + AFD Correction** + Predictive Correction***

where,
  • Predicted MTC is calculated from Figure 5 at the burnup corresponding to the measurement of 300 ppm at RTP conditions,
    • AFD Correction is the more negative value of:

{0 pcm/°F or (AFD

  • AFD Sensitivity)}

where: AFD is the measured AFD minus the predicted AFD from an incore flux map taken at or near the burnup corresponding to 300 ppm, AFD Sensitivity = 0.07 pcm/°F / AFD

      • Predictive Correction is -3 pcm/°F.

The 100 ppm/ARO/RTP-MTC should be less negative than -4.0 x 10-4'k/k/qF.

where: BOL stands for Beginning of Cycle Life ARO stands for All Rods Out EOL stands for End of Cycle Life RTP stands for RATED THERMAL POWER

CORE OPERATING LIMITS REPORT, FNP UNIT 2 CYCLE 31 January 2025 Page 4 of 20 2.4 Shutdown Bank Insertion Limits (Specification 3.1.5) 2.4.1 The shutdown banks shall be withdrawn to a position greater than or equal to 225 steps.

2.5 Control Bank Insertion Limits (Specification 3.1.6) 2.5.1 The control rod banks shall be limited in physical insertion as shown in Figure 1.

2.6 Heat Flux Hot Channel Factor - (Specification 3.2.1) 2.6.1

for P > 0.5

for P d 0.5 where:



§

is the measured value of







2.6.2 2.6.3

is provided in Figure 2.

2.6.4

for P > 0.5

for P d 0.5 where:



§ for P > 0.5



§ for P d 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 8% inclusive,
b. Upper core region, from 92 to 100% inclusive,
c. Grid plane regions, +/- 2% inclusive, and

§ The uncertainty factor (

) used during the Fq surveillance must be consistent with Technical Specification B 3.2.1.

CORE OPERATING LIMITS REPORT, FNP UNIT 2 CYCLE 31 January 2025 Page 5 of 20

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

2.6.5 values are provided in Table 4-1 for ROS1 and Table 4-2 for ROS2.

2.6.6 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 Technical Specification 5.6.5.

2.6.7 The penalty factors account for the potential decrease in transient margin between surveillances. The factors are provided in Table 1-1 for ROS1 and Table 1-2 for ROS2.

2.6.8 Table 5 provides the required limits on THERMAL POWER and the required AFD reductions in the event that additional margin is required.

2.6.9 Either ROS1 or ROS2 may be implemented at any time during the Cycle.

2.6.10 If ROS1 is implemented and entering LCO 3.2.1 Condition B for not within limits, take Action B.1.1 by implementing ROS2.

2.6.11 If ROS2 is implemented and entering LCO 3.2.1 Condition B for not within limits, take Action B.2.1 by using Table 5 to determine required THERMAL POWER and AFD limits based on Required

margin improvement available in ROS2.

2.7 Nuclear Enthalpy Rise Hot Channel Factor -

(Specification 3.2.2)

2.7.1 where



2.7.2

2.7.3 2.8 Axial Flux Difference (Specification 3.2.3) 2.8.1 The Axial Flux Difference (AFD) acceptable operation limits for each RAOC Operating Space (ROS1 and ROS2), and corresponding Required Action (RA1 and RA2) are provided in Figure 3.

CORE OPERATING LIMITS REPORT, FNP UNIT 2 CYCLE 31 January 2025 Page 6 of 20 2.9 Boron Concentration (Specification 3.9.1) 2.9.1 The boron concentration shall be greater than or equal to 2000 ppm.1 2.10 Reactor Core Safety Limits for THERMAL POWER (Specification 2.1.1) 2.10.1 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 safety limits specified in Figure 4.

2.11 Reactor Trip System Instrumentation Overtemperature T (OTT) and Overpower T (OPT)

Setpoint Parameter Values for Table 3.3.1-1 (Specification 3.3.1) 2.11.1 The Reactor Trip System Instrumentation Overtemperature T (OTT) and Overpower T (OPT) setpoint parameter values for TS Table 3.3.1-1 are listed in COLR Tables 2 and 3.

2.12 RCS DNB Parameters for Pressurizer Pressure, RCS Average Temperature, and RCS Total Flow Rate (Specification 3.4.1) 2.12.1 RCS DNB parameters for pressurizer pressure, RCS average temperature, and RCS total flow rate shall be within the limits specified below:

a. Pressurizer pressure t 2209 psig;
b. RCS average temperature d 580.3qF; and
c. The minimum RCS total flow rate shall be t 273,900 GPM when using the precision heat balance method and t 274,800 GPM when using the elbow tap method.

1 This concentration bounds the condition of keff d 0.95 (all rods in less the most reactive rod) and subcriticality (all rods out) over the entire cycle. This concentration includes additional boron to address uncertainties and B10 depletion.

CORE OPERATING LIMITS REPORT, FNP UNIT 2 CYCLE 31 January 2025 Page 7 of 20 Table 1-1 Margin Decrease Factors for ROS1 Cycle Burnup (MWD/MTU)

Cycle Burnup (MWD/MTU)

Cycle Burnup (MWD/MTU) 150 1.0185 7214 1.0112 14278 1.0001 358 1.0201 7422 1.0129 14486 1.0000 566 1.0193 7630 1.0163 14694 1.0000 773 1.0151 7838 1.0184 14902 1.0000 981 1.0115 8045 1.0165 15110 1.0000 1189 1.0084 8253 1.0145 15317 1.0000 1397 1.0060 8461 1.0136 15525 1.0000 1604 1.0032 8669 1.0113 15733 1.0000 1812 1.0046 8876 1.0093 15941 1.0000 2020 1.0074 9084 1.0090 16148 1.0000 2228 1.0111 9292 1.0073 16356 1.0000 2435 1.0141 9500 1.0056 16564 1.0000 2643 1.0168 9707 1.0042 16772 1.0000 2851 1.0182 9915 1.0030 16979 1.0000 3059 1.0179 10123 1.0020 17187 1.0000 3267 1.0165 10331 1.0012 17395 1.0001 3474 1.0144 10539 1.0009 17603 1.0001 3682 1.0131 10746 1.0015 17811 1.0000 3890 1.0118 10954 1.0024 4098 1.0125 11162 1.0057 4305 1.0123 11370 1.0102 4513 1.0109 11577 1.0112 4721 1.0092 11785 1.0118 4929 1.0074 11993 1.0122 5137 1.0056 12201 1.0122 5344 1.0039 12409 1.0117 5552 1.0023 12616 1.0108 5760 1.0011 12824 1.0096 5968 1.0003 13032 1.0048 6175 1.0000 13240 1.0035 6383 1.0000 13447 1.0024 6591 1.0031 13655 1.0016 6799 1.0060 13863 1.0009 7006 1.0082 14071 1.0004 Notes:

1. The Burnup Dependent Transient Margin Decrease Factor, to be applied to in accordance with Technical Specification Surveillance Requirement (SR) 3.2.1.2, is the maximum factor by which is expected to increase over a 39 Effective Full Power Day (EFPD) interval (surveillance interval of 31 EFPD plus the maximum allowable extension not to exceed 25% of the surveillance interval per SR 3.0.2) starting from the burnup at which the was determined.
2. Values may be interpolated to the surveillance cycle burnup.

CORE OPERATING LIMITS REPORT, FNP UNIT 2 CYCLE 31 January 2025 Page 8 of 20 Table 1-2 Margin Decrease Factors for ROS2 Cycle Burnup (MWD/MTU)

Cycle Burnup (MWD/MTU)

Cycle Burnup (MWD/MTU) 150 1.0238 7214 1.0000 14278 1.0202 358 1.0195 7422 1.0000 14486 1.0196 566 1.0161 7630 1.0000 14694 1.0183 773 1.0137 7838 1.0009 14902 1.0165 981 1.0143 8045 1.0041 15110 1.0077 1189 1.0129 8253 1.0067 15317 1.0057 1397 1.0115 8461 1.0098 15525 1.0040 1604 1.0140 8669 1.0132 15733 1.0026 1812 1.0178 8876 1.0135 15941 1.0015 2020 1.0189 9084 1.0099 16148 1.0007 2228 1.0208 9292 1.0103 16356 1.0002 2435 1.0214 9500 1.0148 16564 1.0000 2643 1.0183 9707 1.0152 2851 1.0167 9915 1.0156 3059 1.0144 10123 1.0149 3267 1.0116 10331 1.0148 3474 1.0088 10539 1.0151 3682 1.0081 10746 1.0133 3890 1.0118 10954 1.0112 4098 1.0132 11162 1.0053 4305 1.0134 11370 1.0037 4513 1.0125 11577 1.0024 4721 1.0110 11785 1.0014 4929 1.0093 11993 1.0007 5137 1.0075 12201 1.0002 5344 1.0055 12409 1.0000 5552 1.0023 12616 1.0000 5760 1.0009 12824 1.0000 5968 1.0001 13032 1.0057 6175 1.0000 13240 1.0081 6383 1.0000 13447 1.0169 6591 1.0000 13655 1.0186 6799 1.0000 13863 1.0198 7006 1.0000 14071 1.0203 Notes:

1. The Burnup Dependent Transient Margin Decrease Factor, to be applied to in accordance with Technical Specification Surveillance Requirement (SR) 3.2.1.2, is the maximum factor by which is expected to increase over a 39 Effective Full Power Day (EFPD) interval (surveillance interval of 31 EFPD plus the maximum allowable extension not to exceed 25% of the surveillance interval per SR 3.0.2) starting from the burnup at which the was determined.
2. Values may be interpolated to the surveillance cycle burnup.

CORE OPERATING LIMITS REPORT, FNP UNIT 2 CYCLE 31 January 2025 Page 9 of 20 Table 2 Reactor Trip System Instrumentation - Overtemperature T (OT'T)

Setpoint Parameter Values Tc d 577.2qF Pc = 2235 psig K1 = 1.17 K2 = 0.017/qF K3 = 0.000825/psi W1 t 30 sec W2 d 4 sec W4 = 0 sec W5 d 6 sec W6 d 6 sec f1('I) =

-2.48 {23 + (qt - qb)}

when (qt - qb) d -23% RTP 0% of RTP when -23% RTP < (qt -qb) d 15% RTP 2.05 {(qt - qb) - 15}

when (qt - qb) > 15% RTP

CORE OPERATING LIMITS REPORT, FNP UNIT 2 CYCLE 31 January 2025 Page 10 of 20 Table 3 Reactor Trip System Instrumentation - Overpower T (OP'T)

Setpoint Parameter Values Tcc d 577.2qF K4 = 1.10 K5 = 0.02/qF for increasing Tavg K6 = 0.00109/qF when T > Tcc K5 = 0/qF for decreasing Tavg K6 = 0/qF when T d Tcc W3 t 10 sec W4 = 0 sec W5 d 6 sec W6 d 6 sec f2('I) = 0% RTP for all 'I

CORE OPERATING LIMITS REPORT, FNP UNIT 2 CYCLE 31 January 2025 Page 11 of 20 Table 4-1 Factors for ROS1 Axial Point Elevation (feet) 150 MWD/MTU 1000 MWD/MTU 2000 MWD/MTU 3000 MWD/MTU 4000 MWD/MTU 5000 MWD/MTU 6000 MWD/MTU 1

12.00 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 2

11.80 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 3

11.60 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 4

11.40 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 5

11.20 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 6

11.00 1.1470 1.0919 1.0508 1.0154 1.0051 1.0166 1.0145 7

10.80 1.1298 1.0851 1.0524 1.0249 1.0166 1.0315 1.0346 8

10.60 1.1729 1.1336 1.1133 1.0899 1.0821 1.1002 1.1034 9

10.40 1.2410 1.2051 1.1921 1.1754 1.1689 1.1849 1.1897 10 10.20 1.2560 1.2269 1.2200 1.2111 1.2073 1.2247 1.2358 11 10.00 1.2085 1.1914 1.1876 1.1886 1.1942 1.2005 1.2256 12 9.80 1.2152 1.2024 1.2101 1.2177 1.2192 1.2251 1.2511 13 9.60 1.2804 1.2702 1.2812 1.2941 1.2908 1.2910 1.3145 14 9.40 1.2854 1.2790 1.2864 1.3075 1.3056 1.2993 1.3204 15 9.20 1.2375 1.2352 1.2494 1.2557 1.2583 1.2580 1.2748 16 9.00 1.2189 1.2195 1.2335 1.2335 1.2414 1.2412 1.2611 17 8.80 1.2763 1.2786 1.2917 1.2906 1.2982 1.3092 1.3149 18 8.60 1.3313 1.3352 1.3454 1.3452 1.3501 1.3644 1.3654 19 8.40 1.3219 1.3296 1.3402 1.3465 1.3480 1.3609 1.3632 20 8.20 1.2825 1.2936 1.3082 1.3172 1.3181 1.3285 1.3317 21 8.00 1.3358 1.3494 1.3681 1.3760 1.3758 1.3817 1.3838 22 7.80 1.4400 1.4000 1.4146 1.4214 1.4204 1.4227 1.4238 23 7.60 1.3462 1.3647 1.3890 1.3959 1.3957 1.3967 1.3979 24 7.40 1.2885 1.3090 1.3347 1.3421 1.3430 1.3439 1.3458 25 7.20 1.3009 1.3235 1.3496 1.3564 1.3573 1.3581 1.3587 26 7.00 1.3534 1.3783 1.4037 1.4100 1.4096 1.4112 1.4083 27 6.80 1.4000 1.3865 1.4105 1.4171 1.4196 1.4199 1.4145 28 6.60 1.2990 1.3269 1.3489 1.3586 1.3647 1.3648 1.3588 29 6.40 1.2722 1.3012 1.3204 1.3356 1.3419 1.3412 1.3338 30 6.20 1.3162 1.3467 1.3663 1.3824 1.3876 1.3842 1.3734 31 6.00 1.3047 1.3361 1.3569 1.3738 1.3789 1.3743 1.3620 32 5.80 1.2387 1.2700 1.2918 1.3098 1.3156 1.3114 1.2995 33 5.60 1.1897 1.2263 1.2437 1.2626 1.2688 1.2650 1.2556 34 5.40 1.2164 1.2606 1.2776 1.2984 1.3021 1.2992 1.2834 35 5.20 1.2447 1.2856 1.3163 1.3377 1.3415 1.3384 1.3166 36 5.00 1.2411 1.2801 1.3116 1.3338 1.3381 1.3362 1.3153 37 4.80 1.2355 1.2744 1.3052 1.3278 1.3328 1.3323 1.3120 38 4.60 1.2388 1.2774 1.3072 1.3301 1.3356 1.3363 1.3166 39 4.40 1.2487 1.2866 1.3151 1.3381 1.3440 1.3460 1.3270 40 4.20 1.2321 1.2685 1.2953 1.3180 1.3246 1.3285 1.3114 41 4.00 1.1790 1.2131 1.2374 1.2598 1.2675 1.2739 1.2600 42 3.80 1.1777 1.2099 1.2331 1.2536 1.2618 1.2697 1.2590 43 3.60 1.2232 1.2545 1.2806 1.2946 1.3022 1.3126 1.3043 44 3.40 1.2353 1.2630 1.2901 1.2981 1.3069 1.3201 1.3124 45 3.20 1.2239 1.2474 1.2735 1.2767 1.2869 1.3028 1.2960 46 3.00 1.2253 1.2453 1.2646 1.2749 1.2850 1.2929 1.2925 47 2.80 1.2452 1.2601 1.2764 1.2907 1.3007 1.3017 1.3059 48 2.60 1.2650 1.2782 1.2971 1.3034 1.3132 1.3184 1.3172 49 2.40 1.2466 1.2573 1.2782 1.2769 1.2865 1.2962 1.2901 50 2.20 1.2098 1.2176 1.2391 1.2302 1.2392 1.2531 1.2438 51 2.00 1.2475 1.2551 1.2724 1.2535 1.2609 1.2779 1.2672 52 1.80 1.3057 1.3112 1.3226 1.2938 1.2971 1.3163 1.3037 53 1.60 1.3217 1.3217 1.3258 1.2896 1.2866 1.3073 1.2934 54 1.40 1.3067 1.3003 1.2968 1.2543 1.2451 1.2663 1.2519 55 1.20 1.2944 1.2760 1.2640 1.2144 1.1989 1.2192 1.2033 56 1.00 1.3150 1.2857 1.2590 1.1972 1.1719 1.1878 1.1677 57 0.80 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 58 0.60 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 59 0.40 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 60 0.20 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 61 0.00 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 Notes (per Technical Specification B 3.2.1-11):

1. Top and bottom 5 Axial Points (8%) are excluded.
2. Axial points within +/- 2% of the active core height of a grid location or a bank demand position are excluded.

CORE OPERATING LIMITS REPORT, FNP UNIT 2 CYCLE 31 January 2025 Page 12 of 20 Table 4-1 (Continued)

Factors for ROS1 Axial Point Elevation (feet) 8000 MWD/MTU 10000 MWD/MTU 12000 MWD/MTU 14000 MWD/MTU 16000 MWD/MTU 18000 MWD/MTU 1

12.00 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 2

11.80 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 3

11.60 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 4

11.40 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 5

11.20 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 6

11.00 1.0426 1.0927 1.1276 1.1712 1.1911 1.2210 7

10.80 1.0656 1.1105 1.1448 1.1851 1.2002 1.2299 8

10.60 1.1412 1.1774 1.2059 1.2372 1.2465 1.2789 9

10.40 1.2307 1.2630 1.2837 1.2966 1.2984 1.3354 10 10.20 1.2638 1.2857 1.3029 1.3100 1.3036 1.3397 11 10.00 1.2388 1.2478 1.2630 1.2752 1.2689 1.2917 12 9.80 1.2603 1.2501 1.2659 1.2754 1.2663 1.2750 13 9.60 1.3190 1.3010 1.3076 1.3160 1.3073 1.2923 14 9.40 1.3238 1.3041 1.3061 1.3138 1.3045 1.2843 15 9.20 1.2784 1.2586 1.2635 1.2679 1.2575 1.2528 16 9.00 1.2637 1.2345 1.2443 1.2529 1.2347 1.2402 17 8.80 1.3135 1.2727 1.2854 1.2945 1.2668 1.2781 18 8.60 1.3596 1.3003 1.3229 1.3292 1.2882 1.3026 19 8.40 1.3547 1.2970 1.3199 1.3220 1.2803 1.2911 20 8.20 1.3223 1.2694 1.2911 1.2936 1.2593 1.2748 21 8.00 1.3688 1.3134 1.3315 1.3319 1.2998 1.3165 22 7.80 1.4038 1.3463 1.3610 1.3608 1.3305 1.3483 23 7.60 1.3769 1.3222 1.3353 1.3376 1.3120 1.3322 24 7.40 1.3254 1.2753 1.2877 1.2939 1.2735 1.2964 25 7.20 1.3351 1.2838 1.2932 1.3017 1.2825 1.3061 26 7.00 1.3793 1.3235 1.3284 1.3398 1.3180 1.3411 27 6.80 1.3830 1.3267 1.3284 1.3441 1.3211 1.3440 28 6.60 1.3292 1.2774 1.2784 1.2999 1.2790 1.3023 29 6.40 1.3043 1.2564 1.2542 1.2794 1.2583 1.2816 30 6.20 1.3397 1.2940 1.2864 1.3091 1.2858 1.3093 31 6.00 1.3280 1.2884 1.2778 1.2987 1.2806 1.3024 32 5.80 1.2690 1.2388 1.2278 1.2478 1.2373 1.2584 33 5.60 1.2297 1.2034 1.1894 1.2090 1.2085 1.2236 34 5.40 1.2566 1.2366 1.2286 1.2280 1.2423 1.2577 35 5.20 1.2800 1.2677 1.2599 1.2562 1.2688 1.2818 36 5.00 1.2811 1.2654 1.2598 1.2541 1.2669 1.2776 37 4.80 1.2789 1.2626 1.2576 1.2524 1.2631 1.2703 38 4.60 1.2864 1.2702 1.2638 1.2565 1.2647 1.2690 39 4.40 1.2989 1.2824 1.2743 1.2652 1.2702 1.2701 40 4.20 1.2868 1.2718 1.2634 1.2535 1.2560 1.2524 41 4.00 1.2444 1.2304 1.2234 1.2143 1.2158 1.2097 42 3.80 1.2517 1.2368 1.2247 1.2147 1.2144 1.2033 43 3.60 1.3006 1.2851 1.2665 1.2495 1.2472 1.2345 44 3.40 1.3146 1.3005 1.2827 1.2608 1.2539 1.2439 45 3.20 1.3050 1.2941 1.2793 1.2552 1.2415 1.2353 46 3.00 1.3002 1.2922 1.2808 1.2621 1.2462 1.2383 47 2.80 1.3093 1.3030 1.2962 1.2897 1.2693 1.2660 48 2.60 1.3293 1.3260 1.3201 1.3184 1.2982 1.2973 49 2.40 1.3139 1.3162 1.3130 1.3159 1.3005 1.3015 50 2.20 1.2779 1.2865 1.2915 1.3008 1.2912 1.2960 51 2.00 1.3063 1.3189 1.3223 1.3361 1.3300 1.3366 52 1.80 1.3460 1.3617 1.3667 1.3849 1.3821 1.3910 53 1.60 1.3388 1.3590 1.3681 1.3931 1.3965 1.4104 54 1.40 1.2993 1.3244 1.3390 1.3715 1.3826 1.4030 55 1.20 1.2506 1.2789 1.2982 1.3376 1.3562 1.3834 56 1.00 1.2101 1.2381 1.2600 1.3049 1.3307 1.3654 57 0.80 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 58 0.60 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 59 0.40 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 60 0.20 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 61 0.00 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 Notes (per Technical Specification B 3.2.1-11):

1. Top and bottom 5 Axial Points (8%) are excluded.
2. Axial points within +/- 2% of the active core height of a grid location or a bank demand position are excluded.

CORE OPERATING LIMITS REPORT, FNP UNIT 2 CYCLE 31 January 2025 Page 13 of 20 Table 4-2 Factors for ROS2 Axial Point Elevation (feet) 150 MWD/MTU 1000 MWD/MTU 2000 MWD/MTU 3000 MWD/MTU 4000 MWD/MTU 5000 MWD/MTU 6000 MWD/MTU 1

12.00 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 2

11.80 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 3

11.60 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 4

11.40 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 5

11.20 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 6

11.00 1.0944 1.0613 1.0076 0.9706 0.9640 0.9708 0.9684 7

10.80 1.0783 1.0547 1.0091 0.9800 0.9752 0.9855 0.9893 8

10.60 1.1200 1.0994 1.0676 1.0426 1.0386 1.0516 1.0603 9

10.40 1.1872 1.1650 1.1435 1.1251 1.1224 1.1408 1.1498 10 10.20 1.2071 1.1777 1.1707 1.1600 1.1592 1.1737 1.1830 11 10.00 1.1666 1.1434 1.1402 1.1375 1.1392 1.1441 1.1623 12 9.80 1.1722 1.1539 1.1563 1.1579 1.1608 1.1662 1.1900 13 9.60 1.2292 1.2173 1.2265 1.2339 1.2323 1.2359 1.2538 14 9.40 1.2362 1.2282 1.2342 1.2509 1.2502 1.2499 1.2631 15 9.20 1.1920 1.1886 1.2016 1.2057 1.2087 1.2111 1.2232 16 9.00 1.1763 1.1760 1.1890 1.1883 1.1959 1.1930 1.2137 17 8.80 1.2361 1.2377 1.2499 1.2488 1.2558 1.2529 1.2712 18 8.60 1.2936 1.2974 1.3079 1.3065 1.3119 1.3119 1.3269 19 8.40 1.2851 1.2923 1.3039 1.3056 1.3100 1.3121 1.3259 20 8.20 1.2480 1.2586 1.2711 1.2798 1.2805 1.2848 1.2974 21 8.00 1.3012 1.3143 1.3269 1.3404 1.3400 1.3403 1.3504 22 7.80 1.3425 1.3580 1.3707 1.3883 1.3869 1.3841 1.3918 23 7.60 1.3145 1.3325 1.3460 1.3670 1.3663 1.3627 1.3689 24 7.40 1.2599 1.2799 1.2941 1.3177 1.3182 1.3150 1.3203 25 7.20 1.2741 1.2963 1.3111 1.3355 1.3359 1.3327 1.3357 26 7.00 1.3277 1.3523 1.3686 1.3917 1.3910 1.3876 1.3875 27 6.80 1.4000 1.3628 1.3811 1.4018 1.4010 1.3991 1.3967 28 6.60 1.2791 1.3068 1.3271 1.3453 1.3460 1.3476 1.3448 29 6.40 1.2553 1.2843 1.3061 1.3209 1.3223 1.3274 1.3233 30 6.20 1.3017 1.3321 1.3553 1.3679 1.3695 1.3732 1.3660 31 6.00 1.2933 1.3277 1.3492 1.3626 1.3643 1.3669 1.3582 32 5.80 1.2308 1.2682 1.2877 1.3023 1.3049 1.3077 1.2992 33 5.60 1.1853 1.2263 1.2424 1.2580 1.2616 1.2639 1.2553 34 5.40 1.2170 1.2609 1.2723 1.2889 1.2946 1.2918 1.2813 35 5.20 1.2431 1.2840 1.3032 1.3249 1.3281 1.3173 1.3101 36 5.00 1.2298 1.2671 1.2961 1.3179 1.3220 1.3064 1.3011 37 4.80 1.2203 1.2555 1.2858 1.3082 1.3128 1.2984 1.2926 38 4.60 1.2216 1.2569 1.2861 1.3087 1.3138 1.2999 1.2943 39 4.40 1.2285 1.2633 1.2913 1.3139 1.3193 1.3060 1.3016 40 4.20 1.2094 1.2432 1.2694 1.2918 1.2979 1.2871 1.2838 41 4.00 1.1549 1.1867 1.2106 1.2326 1.2398 1.2356 1.2312 42 3.80 1.1511 1.1815 1.2038 1.2244 1.2320 1.2341 1.2279 43 3.60 1.1932 1.2228 1.2473 1.2625 1.2695 1.2770 1.2693 44 3.40 1.2011 1.2285 1.2543 1.2627 1.2713 1.2829 1.2749 45 3.20 1.1868 1.2110 1.2356 1.2384 1.2486 1.2632 1.2560 46 3.00 1.1846 1.2039 1.2211 1.2348 1.2440 1.2491 1.2505 47 2.80 1.2039 1.2154 1.2256 1.2474 1.2558 1.2512 1.2607 48 2.60 1.2251 1.2321 1.2387 1.2612 1.2689 1.2613 1.2726 49 2.40 1.2090 1.2110 1.2159 1.2370 1.2441 1.2364 1.2474 50 2.20 1.1752 1.1719 1.1739 1.1932 1.1994 1.1915 1.2027 51 2.00 1.2139 1.2033 1.2007 1.2174 1.2214 1.2113 1.2218 52 1.80 1.2713 1.2521 1.2435 1.2568 1.2575 1.2442 1.2532 53 1.60 1.2865 1.2580 1.2425 1.2511 1.2485 1.2325 1.2400 54 1.40 1.2714 1.2343 1.2118 1.2154 1.2092 1.1912 1.1974 55 1.20 1.2590 1.2086 1.1782 1.1757 1.1653 1.1445 1.1486 56 1.00 1.2786 1.2156 1.1724 1.1581 1.1399 1.1132 1.1126 57 0.80 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 58 0.60 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 59 0.40 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 60 0.20 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 61 0.00 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 Notes (per Technical Specification B 3.2.1-11):

1. Top and bottom 5 Axial Points (8%) are excluded.
2. Axial points within +/- 2% of the active core height of a grid location or a bank demand position are excluded.

CORE OPERATING LIMITS REPORT, FNP UNIT 2 CYCLE 31 January 2025 Page 14 of 20 Table 4-2 (Continued)

Factors for ROS2 Axial Point Elevation (feet) 8000 MWD/MTU 10000 MWD/MTU 12000 MWD/MTU 14000 MWD/MTU 16000 MWD/MTU 18000 MWD/MTU 1

12.00 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 2

11.80 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 3

11.60 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 4

11.40 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 5

11.20 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 6

11.00 0.9976 1.0470 1.0769 1.1078 1.1243 1.1567 7

10.80 1.0172 1.0672 1.0940 1.1196 1.1342 1.1622 8

10.60 1.0820 1.1303 1.1517 1.1722 1.1858 1.2060 9

10.40 1.1668 1.2087 1.2245 1.2367 1.2450 1.2573 10 10.20 1.1998 1.2374 1.2482 1.2524 1.2543 1.2636 11 10.00 1.1715 1.2106 1.2184 1.2160 1.2126 1.2246 12 9.80 1.1849 1.2191 1.2247 1.2176 1.2198 1.2160 13 9.60 1.2445 1.2643 1.2736 1.2664 1.2606 1.2417 14 9.40 1.2524 1.2742 1.2751 1.2656 1.2573 1.2321 15 9.20 1.2115 1.2300 1.2323 1.2217 1.2174 1.2030 16 9.00 1.1935 1.2086 1.2193 1.2078 1.1964 1.1898 17 8.80 1.2441 1.2512 1.2611 1.2480 1.2410 1.2303 18 8.60 1.2935 1.2911 1.2958 1.2793 1.2767 1.2739 19 8.40 1.2901 1.2875 1.2906 1.2727 1.2689 1.2727 20 8.20 1.2641 1.2620 1.2619 1.2472 1.2449 1.2546 21 8.00 1.3134 1.3072 1.3021 1.2860 1.2817 1.2947 22 7.80 1.3513 1.3414 1.3325 1.3157 1.3099 1.3261 23 7.60 1.3290 1.3185 1.3096 1.2951 1.2906 1.3111 24 7.40 1.2827 1.2728 1.2656 1.2546 1.2523 1.2774 25 7.20 1.2948 1.2824 1.2750 1.2645 1.2620 1.2897 26 7.00 1.3401 1.3232 1.3147 1.3030 1.2989 1.3280 27 6.80 1.3464 1.3267 1.3192 1.3082 1.3054 1.3349 28 6.60 1.2994 1.2774 1.2742 1.2664 1.2673 1.2978 29 6.40 1.2816 1.2562 1.2541 1.2479 1.2510 1.2813 30 6.20 1.3234 1.2938 1.2864 1.2788 1.2813 1.3094 31 6.00 1.3188 1.2881 1.2778 1.2709 1.2744 1.3009 32 5.80 1.2670 1.2386 1.2278 1.2235 1.2296 1.2553 33 5.60 1.2294 1.2024 1.1910 1.1890 1.1958 1.2210 34 5.40 1.2562 1.2263 1.2185 1.2197 1.2278 1.2477 35 5.20 1.2758 1.2459 1.2455 1.2459 1.2495 1.2704 36 5.00 1.2675 1.2437 1.2411 1.2423 1.2442 1.2649 37 4.80 1.2609 1.2400 1.2357 1.2374 1.2378 1.2566 38 4.60 1.2630 1.2435 1.2369 1.2386 1.2382 1.2545 39 4.40 1.2724 1.2527 1.2434 1.2445 1.2419 1.2545 40 4.20 1.2582 1.2401 1.2293 1.2305 1.2265 1.2362 41 4.00 1.2146 1.1976 1.1867 1.1898 1.1858 1.1937 42 3.80 1.2189 1.2013 1.1870 1.1880 1.1816 1.1859 43 3.60 1.2638 1.2459 1.2281 1.2203 1.2103 1.2086 44 3.40 1.2750 1.2588 1.2413 1.2274 1.2121 1.2099 45 3.20 1.2628 1.2501 1.2346 1.2170 1.2077 1.1991 46 3.00 1.2564 1.2503 1.2343 1.2199 1.2149 1.2050 47 2.80 1.2578 1.2674 1.2554 1.2350 1.2408 1.2311 48 2.60 1.2695 1.2843 1.2791 1.2568 1.2688 1.2599 49 2.40 1.2509 1.2668 1.2702 1.2525 1.2688 1.2632 50 2.20 1.2126 1.2314 1.2480 1.2357 1.2581 1.2570 51 2.00 1.2356 1.2555 1.2762 1.2671 1.2942 1.2955 52 1.80 1.2694 1.2897 1.3176 1.3113 1.3434 1.3472 53 1.60 1.2593 1.2812 1.3177 1.3172 1.3562 1.3651 54 1.40 1.2193 1.2436 1.2884 1.2953 1.3417 1.3572 55 1.20 1.1711 1.1966 1.2481 1.2620 1.3152 1.3375 56 1.00 1.1313 1.1552 1.2105 1.2301 1.2899 1.3194 57 0.80 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 58 0.60 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 59 0.40 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 60 0.20 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 61 0.00 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 Notes (per Technical Specification B 3.2.1-11):

1. Top and bottom 5 Axial Points (8%) are excluded.
2. Axial points within +/- 2% of the active core height of a grid location or a bank demand position are excluded.

CORE OPERATING LIMITS REPORT, FNP UNIT 2 CYCLE 31 January 2025 Page 15 of 20 Table 5 Required THERMAL POWER Limits and AFD Reductions RAOC Operating Space Required FQW(z) Margin Improvement (%)

Required THERMAL POWER Limit (%RTP)

Required AFD Reduction ROS1

> 0

< 50 N/A ROS2 0.3 95 See Figure 3

> 0.3 and 2.5 90

> 2.5

< 50

CORE OPERATING LIMITS REPORT, FNP UNIT 2 CYCLE 31 January 2025 Page 16 of 20 Figure 1 Rod Bank Insertion Limits versus Rated Thermal Power Fully Withdrawn - 225 to 231 steps, inclusive Fully Withdrawn shall be the condition where control rods are at a position within the interval t 225 and d 231 steps withdrawn.

Note: The Rod Bank Insertion Limits are based on the control bank withdrawal sequence A, B, C, D and a control bank tip-to-tip distance of 128 steps.

0 25 50 75 100 125 150 175 200 225 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 Rod Bank Position (Steps Withdrawn)

Fraction of RATED THERMAL POWER Bank D

(.070, 0)

(1, 187)

Bank C (0, 114)

(.552, 225)

CORE OPERATING LIMITS REPORT, FNP UNIT 2 CYCLE 31 January 2025 Page 17 of 20 Figure 2 K(Z) - Normalized FQ(Z) as a Function of Core Height 0

0.2 0.4 0.6 0.8 1

1.2 0

2 4

6 8

10 12 K(Z) - Normalized Peaking Factor Core Height (feet)

Core Height (ft.)

0.000 6.000 12.000 K(Z) 1.000 1.000 1.000 FQ = 2.50

CORE OPERATING LIMITS REPORT, FNP UNIT 2 CYCLE 31 January 2025 Page 18 of 20 Figure 3 Axial Flux Difference Limits as a Function of Rated Thermal Power for ROS1, ROS2, RA1 and RA2 0

10 20 30 40 50 60 70 80 90 100 110

-50

-40

-30

-20

-10 0

10 20 30 40 50 Power (% of RATED THERMAL POWER)

Axial Flux Difference (Delta I) %

ROS1 ROS2 RA1 RA2 ACCEPTABLE OPERATION UNACCEPTABLE OPERATION UNACCEPTABLE OPERATION

CORE OPERATING LIMITS REPORT, FNP UNIT 2 CYCLE 31 January 2025 Page 19 of 20 Figure 4 Reactor Core Safety Limits 560 580 600 620 640 660 680 0

0.2 0.4 0.6 0.8 1

1.2 Tavg (degree F)

Power (Fraction of RATED THERMAL POWER) 2425 psig 2235 psig 1985 psig 1831 psig UNACCEPTABLE OPERATION ACCEPTABLE OPERATION

CORE OPERATING LIMITS REPORT, FNP UNIT 2 CYCLE 31 January 2025 Page 20 of 20 Figure 5 Predicted HFP 300 ppm MTC versus Cycle Burnup Cycle Burnup Moderator Temperature (MWD/MTU)

Coefficient (pcm/°F) 14000

-24.46 15000

-24.71 16000

-24.94 17000

-25.17 18000

-25.41

-25.5

-25.0

-24.5

-24.0 14000 15000 16000 17000 18000 Moderator Temperature Coefficient (pcm/°F)

Cycle Burnup (MWD/MTU)

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