NL-20-1374, Cycle 28 Core Operating Limits Report

Cycle 28 Core Operating Limits Report

ML20344A408
Person / Time
Site:	Farley
Issue date:	12/09/2020
From:	Gayheart C Southern Nuclear Operating Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
NL-20-1374
Download: ML20344A408 (18)

Text

Cheryl A. Gayheart Regulatory Affairs Director 3535 Colonnade Parkway Birmingham, AL 35243 205 992 5316 tel 205 992 7601 fax cagayhea@southernco.com December 9, 2020 Docket No.:

50-364 NL-20-1374 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D. C. 20555-0001 Joseph M. Farley Nuclear Plant - Unit 2 Cycle 28 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 28 Version 1.

This letter contains no NRC commitments. If you have any questions, please contact Jamie Coleman at 205.992.6611.

Respectfully submitted, Cheryl A. Gayheart Regulatory Affairs Director CAG/was

Enclosure:

Core Operating Limits Report for FNP Unit 2 Cycle 28 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 28 Core Operating Limits Report Enclosure Core Operating Limits Report for FNP Unit 2 Cycle 28 Version 1

SOUTHERN<<\\

COMPANY Energy tio Serore Your Wor.ld'i Joseph M. Farley Nuclear Plant Core Operating Limits Report Unit 2 - Cycle 28 Version 1 July 2020

CORE OPERATING LIMITS REPORT, FNP UNIT 2 CYCLE 28 July 2020 Page 1 of 15 1.0 CORE OPERATING LIMITS REPORT This Core Operating Limits Report (COLR) for FNP UNIT 2 CYCLE 28 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 -

)

(Z FQ 3.2.2 Nuclear Enthalpy Rise Hot Channnel Factor -

N H

F' 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 28 July 2020 Page 2 of 15 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, including those 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 28 July 2020 Page 3 of 15 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)}

ZKHUH¨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/°)¨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 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.

CORE OPERATING LIMITS REPORT, FNP UNIT 2 CYCLE 28 July 2020 Page 4 of 15 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 -

)

(Z FQ (Specification 3.2.1) 2.6.1

)

(

)

(

Z K

P F

Z F

RTP Q

Q d

for P > 0.5

)

(

5.0

)

(

Z K

F Z

F RTP Q

Q d

for P d 0.5 where:

POWER THERMAL RATED POWER THERMAL P

2.6.2 50

.2 RTP Q

F 2.6.3 K(Z) is provided in Figure 2.

2.6.4

)

(

)

(

)

(

Z W

P Z

K F

Z F

RTP Q

Q d

for P > 0.5

)

(

5.0

)

(

)

(

Z W

Z K

F Z

F RTP Q

Q d

for P d 0.5 2.6.5 Full Power W(Z) values are provided in Table 4.

Part Power (48% RTP) W(Z) values are provided in Table 5.

2.6.6 The

)

(Z FQ penalty factors are provided in Table 1.

CORE OPERATING LIMITS REPORT, FNP UNIT 2 CYCLE 28 July 2020 Page 5 of 15 2.7 Nuclear Enthalpy Rise Hot Channel Factor -

N H

F' (Specification 3.2.2) 2.7.1









P PF F

F H

RTP H

N H





d 1

1 where:

POWER THERMAL RATED POWER THERMAL P

2.7.2 70

.1 RTP H

F 2.7.3 3

0

'H PF 2.8 Axial Flux Difference (Specification 3.2.3) 2.8.1 The Axial Flux Difference (AFD) acceptable operation limits are provided in Figure 3.

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 (OT'T) and Overpower 'T (OP'T)

Setpoint Parameter Values for Table 3.3.1-1 (Specification 3.3.1) 2.11.1 The Reactor Trip System Instrumentation Overtemperature 'T (OT'T) and Overpower

'T (OP'T) 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 28 July 2020 Page 6 of 15 Table 1 FQ(Z) Penalty Factor Cycle Burnup (MWD/MTU)

FQ(Z) Penalty Factor 0

1.0216 150 1.0216 358 1.0225 566 1.0221 773 1.0206 981 1.0200 2643 1.0200 2851 1.0211 3059 1.0209 3267 1.0207 3475 1.0205 3682 1.0202 3890 1.0200 10331 1.0200 10539 1.0366 10747 1.0379 10955 1.0388 11163 1.0393 11370 1.0392 11578 1.0381 11786 1.0367 11994 1.0348 12201 1.0200 Notes:

1.

The Penalty Factor, to be applied to FQ(Z) in accordance with SR 3.2.1.2, is the maximum factor by which FQ(Z) is expected to increase over a 39 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 FQ(Z) was determined.

2.

Linear interpolation is adequate for intermediate cycle burnups.

3.

For all cycle burnups outside the range of the table, a penalty factor of 1.0200 shall be used.

CORE OPERATING LIMITS REPORT, FNP UNIT 2 CYCLE 28 July 2020 Page 7 of 15 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 28 July 2020 Page 8 of 15 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 28 July 2020 Page 9 of 15 Table 4 RAOC W(Z)

Axial Point Elevation (feet) 150 MWD/MTU 3000 MWD/MTU 6000 MWD/MTU 10000 MWD/MTU 14000 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 1.1742 1.1886 1.2072 1.2466 1.2200 1.2438 7

10.80 1.1708 1.1846 1.2084 1.2429 1.2163 1.2295 8

10.60 1.1660 1.1791 1.2041 1.2369 1.2102 1.2099 9

10.40 1.1609 1.1729 1.2018 1.2304 1.2036 1.1969 10 10.20 1.1553 1.1715 1.1985 1.2236 1.1972 1.1906 11 10.00 1.1491 1.1653 1.1940 1.2164 1.1925 1.1848 12 9.80 1.1499 1.1659 1.1977 1.2087 1.1908 1.1792 13 9.60 1.1508 1.1647 1.2012 1.2008 1.1881 1.1780 14 9.40 1.1495 1.1614 1.2010 1.1939 1.1927 1.1765 15 9.20 1.1460 1.1565 1.1965 1.2027 1.1981 1.1762 16 9.00 1.1457 1.1506 1.1984 1.2195 1.2110 1.1856 17 8.80 1.1631 1.1421 1.2014 1.2307 1.2225 1.1922 18 8.60 1.1768 1.1375 1.2152 1.2413 1.2349 1.1951 19 8.40 1.1878 1.1417 1.2242 1.2530 1.2473 1.2042 20 8.20 1.1964 1.1508 1.2313 1.2632 1.2624 1.2246 21 8.00 1.2028 1.1577 1.2357 1.2701 1.2741 1.2418 22 7.80 1.2073 1.1630 1.2380 1.2744 1.2831 1.2563 23 7.60 1.2087 1.1659 1.2374 1.2755 1.2890 1.2679 24 7.40 1.2087 1.1677 1.2353 1.2749 1.2932 1.2779 25 7.20 1.2060 1.1671 1.2298 1.2701 1.2928 1.2833 26 7.00 1.2016 1.1660 1.2234 1.2626 1.2897 1.2852 27 6.80 1.1959 1.1642 1.2160 1.2537 1.2860 1.2865 28 6.60 1.1882 1.1607 1.2067 1.2427 1.2800 1.2860 29 6.40 1.1796 1.1564 1.1960 1.2299 1.2718 1.2832 30 6.20 1.1701 1.1513 1.1841 1.2155 1.2613 1.2779 31 6.00 1.1596 1.1453 1.1713 1.2000 1.2493 1.2709 32 5.80 1.1482 1.1384 1.1577 1.1836 1.2359 1.2625 33 5.60 1.1379 1.1307 1.1462 1.1675 1.2206 1.2521 34 5.40 1.1300 1.1232 1.1354 1.1584 1.2027 1.2381 35 5.20 1.1296 1.1317 1.1253 1.1583 1.1997 1.2350 36 5.00 1.1383 1.1388 1.1248 1.1582 1.1979 1.2337 37 4.80 1.1456 1.1459 1.1298 1.1589 1.1971 1.2306 38 4.60 1.1527 1.1523 1.1337 1.1584 1.1946 1.2256 39 4.40 1.1591 1.1582 1.1373 1.1569 1.1907 1.2187 40 4.20 1.1647 1.1633 1.1402 1.1544 1.1855 1.2102 41 4.00 1.1694 1.1676 1.1427 1.1511 1.1791 1.2004 42 3.80 1.1736 1.1709 1.1442 1.1461 1.1704 1.1874 43 3.60 1.1767 1.1748 1.1454 1.1400 1.1595 1.1720 44 3.40 1.1811 1.1792 1.1472 1.1370 1.1499 1.1560 45 3.20 1.1840 1.1833 1.1483 1.1346 1.1424 1.1440 46 3.00 1.1966 1.1981 1.1542 1.1341 1.1410 1.1401 47 2.80 1.2183 1.2259 1.1722 1.1356 1.1523 1.1483 48 2.60 1.2450 1.2561 1.1933 1.1368 1.1668 1.1623 49 2.40 1.2727 1.2861 1.2141 1.1452 1.1808 1.1761 50 2.20 1.3007 1.3167 1.2354 1.1575 1.1951 1.1902 51 2.00 1.3287 1.3472 1.2562 1.1690 1.2081 1.2029 52 1.80 1.3563 1.3773 1.2766 1.1801 1.2206 1.2156 53 1.60 1.3826 1.4058 1.2963 1.1912 1.2333 1.2295 54 1.40 1.4076 1.4329 1.3151 1.2023 1.2460 1.2438 55 1.20 1.4310 1.4581 1.3328 1.2130 1.2585 1.2578 56 1.00 1.4524 1.4810 1.3490 1.2233 1.2708 1.2717 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 Top and bottom 5 axial points excluded per Technical Specification B3.2.1.

CORE OPERATING LIMITS REPORT, FNP UNIT 2 CYCLE 28 July 2020 Page 10 of 15 Table 5 Part Power (48%) RAOC W(Z)

Axial Point Elevation (feet) 150 MWD/MTU 1

12.00 1.0000 2

11.80 1.0000 3

11.60 1.0000 4

11.40 1.0000 5

11.20 1.0000 6

11.00 1.3184 7

10.80 1.3052 8

10.60 1.2827 9

10.40 1.2575 10 10.20 1.2295 11 10.00 1.2111 12 9.80 1.1929 13 9.60 1.1684 14 9.40 1.1495 15 9.20 1.1282 16 9.00 1.1099 17 8.80 1.1130 18 8.60 1.1157 19 8.40 1.1164 20 8.20 1.1180 21 8.00 1.1180 22 7.80 1.1181 23 7.60 1.1156 24 7.40 1.1135 25 7.20 1.1107 26 7.00 1.1072 27 6.80 1.1027 28 6.60 1.0980 29 6.40 1.0914 30 6.20 1.0802 31 6.00 1.0721 32 5.80 1.0660 33 5.60 1.0637 34 5.40 1.0578 35 5.20 1.0619 36 5.00 1.0760 37 4.80 1.0886 38 4.60 1.1012 39 4.40 1.1131 40 4.20 1.1243 41 4.00 1.1348 42 3.80 1.1462 43 3.60 1.1567 44 3.40 1.1682 45 3.20 1.1783 46 3.00 1.1980 47 2.80 1.2269 48 2.60 1.2601 49 2.40 1.2946 50 2.20 1.3295 51 2.00 1.3663 52 1.80 1.4027 53 1.60 1.4378 54 1.40 1.4724 55 1.20 1.5062 56 1.00 1.5373 57 0.80 1.0000 58 0.60 1.0000 59 0.40 1.0000 60 0.20 1.0000 61 0.00 1.0000 Top and bottom 5 axial points excluded per Technical Specification B3.2.1.

CORE OPERATING LIMITS REPORT, FNP UNIT 2 CYCLE 28 July 2020 Page 11 of 15 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 28 July 2020 Page 12 of 15 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 28 July 2020 Page 13 of 15 Figure 3 Axial Flux Difference Limits as a Function of Rated Thermal Power for RAOC

(-12, 100)

(-25, 50)

(+9, 100)

(+24, 50) 0 10 20 30 40 50 60 70 80 90 100 110 120

-60

-50

-40

-30

-20

-10 0

10 20 30 40 50 60 Power (% of RATED THERMAL POWER)

Axial Flux Difference (Delta I) %

UNACCEPTABL E OPERATION UNACCEPTABL E OPERATION UNACCEPTABLE OPERATION UNACCEPTABLE OPERATION ACCEPTABLE OPERATION

CORE OPERATING LIMITS REPORT, FNP UNIT 2 CYCLE 28 July 2020 Page 14 of 15 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 28 July 2020 Page 15 of 15 Figure 5 Predicted HFP 300 ppm MTC versus Cycle Burnup Cycle Burnup Moderator Temperature (MWD/MTU)

Coefficient (pcm/°F) 16000

-25.12 17000

-25.34 18000

-25.60 19000

-25.85 20000

-26.11

-26.5

-26.0

-25.5

-25.0 16000 17000 18000 19000 20000 Moderator Temperature Coefficient (pcm/°F)

Cycle Burnup (MWD/MTU)