ML092940244

Revisions 2 and 3 to the Cycle 10 Core Operating Limits Report

ML092940244
Person / Time
Site:	Watts Bar
Issue date:	10/19/2009
From:	Krich R Tennessee Valley Authority
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
Download: ML092940244 (16)

Text

Tennessee Valley Authority, 1101 Market Street, Chattanooga, Tennessee 37402-2801 October 19, 2009 10 CFR 50.4 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D.C. 20555-0001 Watts Bar Nuclear Plant, Unit 1 Facility Operating License No. NPF-90 NRC Docket No.:50-390

Subject:

Revisions 2 and 3 of the Cycle 10 Core Operating Limits Report The purpose of this letter is to provide Revisions 2 and 3 of the Cycle 10 Core Operating Limits Report (COLR) in accordance with Watts Bar Nuclear Plant, Technical Specification 5.9.5.d. Revisions 0 and 1 of the COLR were never issued for use during Cycle 10. Revision 2 provided the boron concentrations required for reloading the core and entry into Mode 6 and Mode 5. Revision 3 defines the core operating limits for Cycle 10 operation.

There are no regulatory commitments contained in this letter or its enclosures.

Please direct any questions conderning this matter to Kevin Casey at (423) 751-8523.

Respectfully, R. M. Kric Vice President Nuclear Licensing Enclosures 1. Revision 2 of the Cycle 10 COLR

2. Revision 3 of the Cycle 10 COLR Printed on recycled paper

U.S. Nuclear Regulatory Commission Page 2 October 19, 2009 Enclosures cc (Enclosures):

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

Enclosure 1 Cycle 10 Core Operating Limits Report Revision 2

.l E1-1 of 3

COLR for Watts Bar Unit 1, Cycle 10 QA Record L36 091001 802 WATTS BAR NUCLEAR PLANT, UNIT 1, CYCLE 10 MODE 6 AND RESTRICTED MODE 5 CORE OPERATING LIMITS REPORT Revision 2 October 2009 Prepared by: **4 ,I,)(/

Nuclear Fuel / Date Reviewed by:

/0 1 Manager, Nuclear F4 Engineeing Date Reactor Engineering Supervisor Date Approved by: ,4/ //o PORC Chairman ,Date

__', ,oQA Plant Manager Date Date of PORC PORC Meeting Affected Revision Approval Number Pages Reason for Revision 0 n/a n/a n/a not issued 1 n/a n/a n/a not issued 2 1tol &16 16.-1, all initial issue Unit 1 Cycle 10 Watts Bar Page 1 of 2 Revision 2 E1-2 of 3

Mode 6 and Restricted Mode 5 COLR for Watts Bar Unit 1, Cycle 10 1.0 CORE OPERATING LIMITS REPORT This Core Operating Limits Report (COLR) for Watts Bar Unit 1 Cycle 10 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 (FAHN) 3.2.3 Axial Flux Difference (AFD) 3.5.1 Accumulators 3.5.4 Refueling Water Storage Tank (RWST) 3.9.1 Boron Concentration 2.0 OPERATING LIMITS This COLR is only valid for mode 6 and restricted mode 5. The mode 5 restriction does not allow the control rod drive system to withdraw any RCCA. The COLR must be revised before the withdrawal of the RCCAs by the control rod drive system is enabled. The cycle-specific parameter limits for specifications 3.1.4, 3.1.6, 3.1.7, 3.2.1, 3.2.2, and 3.2.3 are not applicable in mode 6 or restricted mode 5 and are not provided. The parameter limits for the specifications 3.5.1, 3.5.4, and 3.9.1 are provided in the following subsections. These limits have been developed using the NRC approved methodologies specified in the Technical Specifications Section 5.9.5.

2.1 REFUELING BORON CONCENTRATION (LCO 3.9.1) 2.1.1 The refueling boron concentration shall be a 2000 ppm.

2.2 ACCUMULATORS (LCO 3.5.1) 2.2.1 There are 240 tritium producing bumable absorber rods (TPBARs) in the reactor core for Cycle 10.

2.3 REFUELING WATER STORAGE TANK - RWST (LCO 3.5.4) 2.3.1 There are 240 tritium producing burnable absorber rods (TPBARs) in the reactor core for Cycle 10.

Unit 1 Cycle 10 Watts Bar Page 2 of 2 Revision 2 E1-3 of 3

Enclosure 2 Cycle 10 Core Operating Limits Report Revision 3 E2-1 of 11

COLR for Watts Bar Unit 1, Cycle 10 QA Record L36 091009 807 WATTS BAR NUCLEAR PLANT, UNIT 1, CYCLE 10 CORE OPERATING LIMITS REPORT Revision 3 October 2009 Prepared by:

Nuclear Fuel Date' Reviewed by: * /0/,/,S Manager, Nuclear FX E~ngineering Date Reactor Engineering Supervisor Date Date of PORC PORC Meeting Affected Revision Approval Number Pages Reason for Revision 0 n/a n/a n/a not issued 1 n/a n/a n/a not issued 2 1016/09 4273 all Initial issue 3 10/9/09 - all revised to remove mode restriction Unit 1 Cycle 10 Watts Bar Page 1 of 10 Revision 3 E2-2 of 11

1.0 CORE OPERATING LIMITS REPORT This Core Operating Limits Report (COLR) for Watts Bar Unit 1 Cycle 10 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 (FAHN) 3.2.3 Axial Flux Difference (AFD) 3.5.1 Accumulators 3.5.4 Refueling Water Storage Tank (RWST) 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 1 Cycle 10 WATTS BAR Page 2 of 10 Revision 2 E2-3 of 11

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 Ak/k/°F (upper limit). With the measured BOL/ARO/HZP - MTC more positive than -0.60 x 10-5 Ak/k/°F (as-measured MTC limit), establish control rod withdrawal limits to ensure the MTC remains less positive than or equal to 0 Ak/k/°F (upper limit) for all times in core life.

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

-4.5 x 10-4 Ak/k/IF (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 -3.75 x 10-4 Ak/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 -4.28 x 10-4 Ak/k/ 0 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 1 Cycle 10 WATTS BAR Page 3 of 10 Revision 3 E2-4 of 11

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/P1

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

Unit 1 Cycle 10 WATTS BAR Page 4 of 10 Revision 3 E2-5 of 11

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

FAHN < FAHRTP * (1 + PF * (i-P))

where P = Thermal Power / Rated Thermal Power FAHRTP = 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 10 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.

2.8 ACCUMULATORS (LCO 3.5.1) 2.8.1 There are 240 tritium producing burnable absorber rods (TPBARs) in the reactor core for Cycle 10.

2.9 REFUELING WATER STORAGE TANK - RWST (LCO 3.5.4) 2.9.1 There are 240 tritium producing burnable absorber rods (TPBARs) in the reactor core for Cycle 10.

Unit 1 Cycle 10 WATTS BAR Page 5 of 10 Revision 3 E2-6 of 11

I-a-

W I-0 0

(L I-.

z 0

0.0 0.2 0.4 0.6 0.8 1.0 FRACTIONAL 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 Ž 225 and _< 231 steps withdrawn.

Unit 1 Cycle 10 WATTS BAR Page 6 of 10 Revision 3 E2-7 of 11

1.2 1.1 1.0 0.9 0.8 0 0.7 CU 0.6 Core Heiqht K(Z) 0.000 1.000 N 6.000 1.000 E 12.000 0.9256 0.5 0

z 0.4 0.3 0.2 0.1 0

0 2 4 6 8 10 12 Core Height (feet)

Figure 2 K(Z) - Normalized FQ(Z) as a Function of Core Height Unit 1 Cycle 10 WATTS BAR Page 7 of 10 Revision 3 E2-8 of 11

120 110 100 90 80 0) 70 E

60 50 40 30 20 10 0

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

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

I nit 1 Cycle 10 VATTS BAR Page 8 of 10 Revision 3 E2-9 of 11

Table A. 1 FQW(Z) = FQC(Z)

• W(Z)

Max W(z) at 150 Max W(z) at 150 Max W(z) at 150 Max W(z) at Max W(z) at MWD/MTU MWD/MTU MWD/MTU Max W(z) at 3000 10000 16000 Height (ft) (30% Power) (75% Power) (100% Power) MWD/MTU MWD/MTU MWD/MTU 12.0000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 11.8000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 11.6000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 11.4000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 11.2000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 11.0000 1.0000 1.0000 1.0000 .1.0000 1.0000 1.0000 10.8000 1.2811 1.3035 1.1893 1.1903 1.2164 1.2015 10.6000 1.2651 1.2796 1.1864 1.1869 1.2167 1.2033 10.4000 1.2458 1.2508 1.1812 1.1814 1,2157 1.2055 10.2000 1.2262 1.2218 1.1746 1.1745 1.2122 1.1986 10.0000 1.2058 1.1915 1.1672 1.1668 1.2071 1.1848 9.8000 1.1833 1.1622 1.1585 1.1585 1.2007 1.1817 9.6000 1.1615 1.1386 1.1512 1.1606 1.1933 1.1827 9.4000 1.1466 1.1243 1.1515 1.1702 1.1846 1.1826 9.2000 1.1416 1.1225 1.1606 1.1693 1.1754 1.1814 9.0000 1.1316 1.1182 1.1647 1.1666 1.1727 1.1902 8.8000 1.1249 1.1198 1.1727 1.1689 1.1747 1.2049 8.6000 1.1238 1.1295 1.1882 1.1790 1.1857 1.2229 8.4000 1.1230 1.1421 1.2052 1.1929 1.2010 1.2426 8.2000 1.1193 1.1520 1.2186 1.2033 1.2127 1.2588 8.0000 1.1135 1.1597 1.2291 1.2114 1.2222 1.2723 7.8000 1.1062 1.1658 1.2370 1.2173 1.2293 1.2830 7.6000 1.1013 1.1701 1.2422 1.2208 t 1.2340 1.2906 7.4000 1.0967 1.1728" 1.2447 1.2221 . 1.2363 1.2952 7.2000 1.0922 1.1733 1.2448 1.2212 1.2363 1.2969 7.0000 1.0873 1.1712 1.2425 1.2186 1.2340 1.2957 6.8000 1.0824 1.1670 1.2380 1.2144 1.2300 1.2917 6.6000 1.0774 1.1621 1.2312 1.2087 1.2245 1.2852 6.4000 1.0727 1.1564 1.2227 1.2009 1.2171 1.2761 6.2000 1.0692 1.1512 1.2141 1.1914 1.2079 1.2646 6.0000 1.0660 1.1470 1.2065 1.1827 1.1971 1.2509 5.8000 1.0622 1.1419 1.1976 1.1746 1.1840 1.2349 5.6000 . 1.0596 1.1370 1.1888 1.1677 1.1717 1.2173 5.4000 1.0603 1.1344 1.1823 1.1630 1.1640 1.1992 5.2000 1.0633 1.1332 1.1772 1.1603 1.1591 1.1833 5.0000 1.0675 1.1336 1.1735 1.1574 1.1535 1.1778 4.8000 1.0725 1.1347 1.1702 1.1558 1.1487 1.1752 4.6000 1.0788 1.1363 1.1677 1.1550 1.1445 1.1698 4.4000 1.0874 1.1392 1.1670 1.1533 1.1402 1.1639 4.2000 1.0964 1.1415 1.1661 1.1531 1.1378 1.1571 4.0000 1.1047 1.1437 1.1645 1.1532 1.1353 1.1490 3.8000 1.1150 1.1482 1.1650 1.1558 1.1322 1.1430 3.6000 1.1277 1.1550 1.1676 1.1620 1.1311 1.1415 3.4000 1.1405 1.1611 1.1693 1.1698 1.1330 1.1417 3.2000 1.1558 1.1692 1.1727 1.1771 1.1344 1.1414 3.0000 1,1780 1.1842 1.1830 1.1848 1.1418 1.1436 2.8000 1.2044 1.2034 1.1977 1.1990 1.1567 1.1472 2.6000 1.2351 1.2266 1.2163 1.2187 1.1753 1.1531 2.4000 1.2722 1.2556 1.2412 1.2376 1.1934 1.1662 2.2000 1.3089 1.2835 1.2656 1.2611 1.2114 1.1812 2.0000 1.3426 1.3097 1.2881 1.2849 1.2290 1.1960 1.8000 1.3765 1.3405 1.3140 1.3079 1.2459 1.2102 1.6000 1.4144 1.3780 1.3456 1.3345 1.2619 1.2236 1.4000 1.4594 1.4165 1.3786 1.3664 1.2760 1.2356 1.2000 1.5070 1.4521 1.4087 1.3953 1.2874 1.2450 1.0000 1.0000 1,0000 1.0000 1.0000 1.0000 1.0000 0.8000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 0.6000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 0.4000 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 0.2000 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 Unit 1 Cycle 10 WATTS BAR Page 9 of 10 Revision 3 E2-10 of 11

Table A.2 FQW(Z) Penalty Factor Core FQW(Z)

Burnup Penalty (MWD/MTU) Factor All Burnups 1.0200 Note:

1. The Penalty Factor, which is applied to FQw(Z) for compliance with Surveillance Requirement 3.2.1.2.a, 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 1 Cycle 10 WATTS BAR Page 10 of 10 Revision 3 E2-11 of 11