ML17324B383

Revision 0 of the Unit 2 Cycle Core Operating Limits Report (COLR)

ML17324B383
Person / Time
Site:	Watts Bar
Issue date:	11/20/2017
From:	Simmons P Tennessee Valley Authority
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
Download: ML17324B383 (13)

Text

Tennessee Valley Authority, Post Office Box 2000, Spring City, Tennessee 3738 1-2000 November 20, 20 17 10 CFR 50.4 ATTN: Document Control Desk U.S. Nuclear Regu latory Com mission Washington, D.C. 20555-0001 Watts Bar Nuclear Plant, Unit 2 Faci lity Operating License No. NPF-96 NRC Docket No. 50-391

Subject:

REVISION 0 OF THE UNIT 2 CYCLE 2 CORE OPERATING LIMITS REPORT (COLR)

Pursuant to Watts Bar Nuclear Plant Techn ical Specifications Section 5.9.5.d, Tennessee Valley Authority (TVA) has enclosed Revision 0 of the Unit 2 Cycle 2 COLR. The ana lytica l methods used to determine the core operating limits were previously reviewed and approved by the NRC.

There are no regu latory comm itments contained in th is letter or the enclosu re.

Should you have questions regard ing this submittal, please contact Kim Hulvey at (423) 365-7720.

Respectful ly,

~

Paul Simm ons Site Vice President Watts Bar Nuclear Pla nt

Enclosure:

Watts Bar Nuclear Plant, Unit 2, Cycle 2 Core Operating Limits Report Revision 0 November 201 7

U.S. Nuclear Regulatory Commission Page 2 November 20, 2017 cc (Enclosure):

NRC Regional Administrator - Region II NRR Project Manager - Watts Bar Nuclear Plant NRC Senior Resident Inspector - Watts Bar Nuclear Plant

ENCLOSURE Watts Bar Nuclear Plant, Unit 2, Cycle 2 Core Operating Limits Report Revision 0 November 2017

QA Record L36171016 801 WATTS BAR NUCLEAR PLANT, UNIT 2, CYCLE 2 CORE OPERA TING LIMITS REPORT Revision 0 November 2017 Prepared by:

~~ \ \ - (o ... 201 ::r Date

.11/6/2011 I

W. Andrew Whitener. Nuclear Fuel Programs & Oversight Date Reviewed by:

Christine A. Setter. Manager: PWR\lel Engineering Date

/l/)L/ 17 Date Approved by:

~,,. c_'

, N~~

Plant Manager Date Date of PORC Affected Revision Approval Pages Reason for Revision 0 See above All Initial issue Unit 2 Cycle 2 Watts Bar Page 1 of 10 Revision 0

1.0 CORE OPERATING LIMITS REPORT This Core Operating Limits Report (COLR) for Watts Bar Unit 2 Cycle 2 has been prepared in accordance with the requirements of the Technical Specifications 5.9.5.

The Technical Specifications affected by this report are listed below:

3.1.4 Moderator Temperature Coefficient (MTC) 3.1.6 Shutdown Bank Insertion Limits 3.1.7 Control Bank Insertion Limits 3.2.1 Heat Flux Hot Channel Factor (FQ(Z))

3.2.2 Nuclear Enthalpy Rise Hot Channel Factor (FHN) 3.2.3 Axial Flux Difference (AFD) 3.9.1 Boron Concentration 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 Section 5.9.5.

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 Unit 2 Cycle 2 WATTS BAR Page 2 of 10 Revision 0

2.1 MODERATOR TEMPERATURE COEFFICIENT - MTC (LCO 3.1.4) 2.1.1 The MTC limits are:

The ARO/HZP - MTC shall be less positive than or equal to 0 k/k/F (upper limit).

With the measured BOL/ARO/HZP - MTC more positive than -2.25 x 10-5 k/k/F (as-measured 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

-4.50 x 10-4 k/k/F (lower limit).

2.1.2 The 300 ppm surveillance limit is:

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

-3.65 x 10-4 k/k/F.

2.1.3 The 60 ppm surveillance limit is:

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

-4.18 x 10-4 k/k/F.

2.2 SHUTDOWN BANK INSERTION LIMITS (LCO 3.1.6) 2.2.1 The shutdown banks shall be withdrawn to a position greater than or equal to 225 steps withdrawn.

2.3 CONTROL BANK INSERTION LIMITS (LCO 3.1.7) 2.3.1 The control banks are fully withdrawn or shall be limited in physical insertion as shown in Figure 1.

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

2.3.3 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.

Unit 2 Cycle 2 WATTS BAR Page 3 of 10 Revision 0

2.3.4 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 (steps) 225 109 116 226 110 116 227 111 116 228 112 116 229 113 116 230 114 116 231 115 116 2.4 HEAT FLUX HOT CHANNEL FACTOR - FQ(Z) (LCO 3.2.1)

FQ(Z) [CFQ / P]

• K(Z) for P > 0.5 FQ(Z) [CFQ / 0.5]

• K(Z) for P 0.5 Where P = Thermal Power / Rated Thermal Power 2.4.1 CFQ = 2.50 2.4.2 K(Z) is provided in Figure 2.

2.4.3 FQW(Z) = FQc(Z)

• W(Z)/P for P > 0.5 FQW(Z) = FQc(Z)

• W(Z)/0.5 for P 0.5 where: W(Z) values are provided in Table A.1. The table provides sufficient information to determine W(Z) versus core height for all cycle burnups.

2.4.4 Part power W(Z) values are only required to be used when the part power surveillance is performed using the fixed incore detector system.

2.4.5 FQW(Z) Penalty Factor The FQW(Z) penalty factor is provided in Table A.2.

Unit 2 Cycle 2 WATTS BAR Page 4 of 10 Revision 0

2.5 NUCLEAR ENTHALPY RISE HOT CHANNEL FACTOR - FHN (LCO 3.2.2)

FHN FHRTP * ( 1 + PF * ( 1-P))

where P = Thermal Power / Rated Thermal Power FHRTP = 1.65 for RFA-2 fuel, and PF = 0.3 2.6 AXIAL FLUX DIFFERENCE - AFD (LCO 3.2.3) 2.6.1 The AFD limits for Cycle 2 are provided in Figure 3.

2.7 REFUELING BORON CONCENTRATION (LCO 3.9.1) 2.7.1 The refueling boron concentration shall be 2000 ppm.

Unit 2 Cycle 2 WATTS BAR Page 5 of 10 Revision 0

250 BANK A (ALL POWERS, 225) 225 (0.197, 225) (0.703, 225) 200 BANK B (1.0, 177)

ROD BANK STEP POSITION (STEPS WITHDRAWN) 175 (0.0, 180) 150 BANK C 125 100 BANK D 75 (0.0, 64) 50 25 (0.227, 0) 0 0.0 0.2 0.4 0.6 0.8 1.0 FRACTION OF RATED THERMAL POWER Figure 1 Control Bank Insertion Limits Versus Thermal Power Four Loop Operation

• 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 2 WATTS BAR Page 6 of 10 Revision 0

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 2 K(Z) - Normalized FQ(Z) as a Function of Core Height Unit 2 Cycle 2 WATTS BAR Page 7 of 10 Revision 0

120 110

(-12, 100) (7, 100) 100 90 Acceptable Operation 80 Unacceptable Unacceptable Operation Operation

% of Rated Thermal Power 70 60 50

(-28, 50) (21, 50) 40 30 20 Figure 3 Axial Flux Difference Acceptable Operation Limits as a 10 Function of Rated Thermal Power (RAOC) 0

-50 -40 -30 -20 -10 0 10 20 30 40 50 Flux Difference ( I) %

Figure 3 Figure 3 Axial Flux Difference Acceptable Operation Limits as a function of Rated Thermal Power (RAOC)

Unit 2 Cycle 2 WATTS BAR Page 8 of 10 Revision 0

Table A.1 RAOC W(Z) Surveillance Factors Height (ft) Max W(z) Max W(z) Max W(z) Max W(z) Max W(z) Max W(z) Max W(z) Max W(z) at 150 at 150 at 150 at 2000 at 6000 at 10000 at 14000 at 16000 MWD/MTU MWD/MTU MWD/MTU MWD/MTU MWD/MTU MWD/MTU MWD/MTU MWD/MTU (30% Power) (75% Power) (100% Power) (100% Power) (100% Power) (100% Power) (100% Power) (100% Power) 12.0720 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 11.8708 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 11.6696 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 11.4684 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 11.2672 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 11.0660 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 10.8648 1.4084 1.4573 1.3286 1.3235 1.3275 1.1820 1.1574 1.1531 10.6636 1.3886 1.4287 1.3221 1.3185 1.3127 1.1773 1.1526 1.1487 10.4624 1.3626 1.3906 1.3150 1.3166 1.2897 1.1718 1.1469 1.1435 10.2612 1.3419 1.3633 1.3060 1.3114 1.2662 1.1651 1.1405 1.1378 10.0600 1.3171 1.3310 1.2952 1.3032 1.2594 1.1574 1.1332 1.1363 9.8588 1.2934 1.3014 1.2879 1.2941 1.2318 1.1495 1.1255 1.1340 9.6576 1.2774 1.2876 1.2822 1.2843 1.2230 1.1417 1.1173 1.1311 9.4564 1.2529 1.2636 1.2746 1.2728 1.2229 1.1387 1.1180 1.1292 9.2552 1.2254 1.2344 1.2653 1.2599 1.2213 1.1456 1.1264 1.1386 9.0540 1.2019 1.2085 1.2586 1.2507 1.2188 1.1508 1.1370 1.1465 8.8528 1.1866 1.2133 1.2640 1.2580 1.2126 1.1532 1.1444 1.1529 8.6516 1.1766 1.2171 1.2719 1.2614 1.2131 1.1557 1.1584 1.1655 8.4504 1.1639 1.2139 1.2763 1.2628 1.2261 1.1621 1.1803 1.1847 8.2492 1.1554 1.1989 1.2784 1.2662 1.2377 1.1704 1.1991 1.2052 8.0480 1.1440 1.2113 1.2858 1.2751 1.2464 1.1778 1.2156 1.2244 7.8468 1.1366 1.2222 1.2939 1.2809 1.2525 1.1881 1.2297 1.2410 7.6456 1.1296 1.2185 1.2967 1.2824 1.2547 1.1955 1.2405 1.2542 7.4444 1.1238 1.2126 1.2968 1.2813 1.2548 1.2012 1.2494 1.2654 7.2432 1.1152 1.2074 1.2936 1.2770 1.2517 1.2042 1.2549 1.2729 7.0420 1.1046 1.2055 1.2883 1.2706 1.2465 1.2053 1.2577 1.2775 6.8408 1.0953 1.1977 1.2801 1.2616 1.2392 1.2043 1.2581 1.2794 6.6396 1.0883 1.1873 1.2687 1.2500 1.2298 1.2015 1.2561 1.2785 6.4384 1.0843 1.1782 1.2561 1.2370 1.2189 1.1976 1.2523 1.2760 6.2372 1.0678 1.1667 1.2420 1.2227 1.2065 1.1922 1.2464 1.2709 6.0360 1.0577 1.1543 1.2259 1.2066 1.1924 1.1851 1.2383 1.2634 5.8348 1.0505 1.1407 1.2075 1.1885 1.1768 1.1765 1.2280 1.2535 5.6336 1.0458 1.1274 1.1880 1.1695 1.1602 1.1667 1.2157 1.2414 5.4324 1.0318 1.1132 1.1695 1.1537 1.1485 1.1599 1.2051 1.2294 5.2312 1.0266 1.1062 1.1585 1.1462 1.1413 1.1591 1.2067 1.2304 5.0300 1.0316 1.1052 1.1528 1.1403 1.1382 1.1599 1.2081 1.2301 4.8288 1.0351 1.1029 1.1455 1.1334 1.1372 1.1636 1.2083 1.2281 4.6276 1.0375 1.1001 1.1376 1.1257 1.1354 1.1660 1.2079 1.2244 4.4264 1.0391 1.0962 1.1288 1.1173 1.1329 1.1677 1.2064 1.2189 4.2252 1.0397 1.0907 1.1190 1.1081 1.1297 1.1684 1.2035 1.2127 4.0240 1.0455 1.0861 1.1084 1.0982 1.1257 1.1683 1.1993 1.2060 3.8228 1.0506 1.0811 1.0973 1.0875 1.1210 1.1674 1.1936 1.1975 3.6216 1.0439 1.0727 1.0860 1.0789 1.1159 1.1651 1.1862 1.1870 3.4204 1.0456 1.0669 1.0758 1.0775 1.1109 1.1682 1.1844 1.1797 3.2192 1.0556 1.0661 1.0698 1.0774 1.1111 1.1714 1.1851 1.1760 3.0180 1.0666 1.0694 1.0685 1.0799 1.1150 1.1777 1.1882 1.1773 2.8168 1.0865 1.0820 1.0766 1.0958 1.1296 1.1880 1.2031 1.1943 2.6156 1.1158 1.1038 1.0937 1.1178 1.1542 1.2035 1.2225 1.2124 2.4144 1.1444 1.1246 1.1097 1.1387 1.1777 1.2252 1.2405 1.2303 2.2132 1.1803 1.1476 1.1261 1.1604 1.2020 1.2484 1.2586 1.2482 2.0120 1.2165 1.1715 1.1429 1.1824 1.2265 1.2710 1.2758 1.2652 1.8108 1.2460 1.1940 1.1596 1.2043 1.2505 1.2927 1.2919 1.2811 1.6096 1.2780 1.2149 1.1752 1.2249 1.2732 1.3130 1.3072 1.2962 1.4084 1.3122 1.2344 1.1897 1.2439 1.2941 1.3318 1.3219 1.3108 1.2072 1.3431 1.2528 1.2030 1.2614 1.3132 1.3488 1.3355 1.3246 1.0060 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 0.8048 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 0.6036 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 0.4024 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 0.2012 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 0.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 Unit 2 Cycle 2 WATTS BAR Page 9 of 10 Revision 0

Table A.2 FQW(Z) Penalty Factor Burnup Penalty (MWD/MTU) Factor 150 1.0237 300 1.0244 451 1.0250 601 1.0254 751 1.0253 902 1.0248 1052 1.0237 1203 1.0221 1353 1.0201 1503 1.0200 11715 1.0200 11863 1.0203 12012 1.0206 12160 1.0210 12308 1.0209 12456 1.0205 12605 1.0201 12753 1.0200 Note:

1. The Penalty Factor, which is applied to FQW(Z) for compliance with Surveillance Requirement 3.2.1.2, is the maximum factor by which FQW(Z) is expected to increase per 31 Effective Full Power Days (EFPD) starting from the burnup at which the FQW(Z) was determined.

Unit 2 Cycle 2 WATTS BAR Page 10 of 10 Revision 0