NOC-AE-03001570, Cycle 12 Core Operating Limits Report, Revision 1

Cycle 12 Core Operating Limits Report, Revision 1

ML032250089
Person / Time
Site:	South Texas
Issue date:	08/05/2003
From:	Leazar D South Texas
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
NOC-AE-03001570
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Nuclear Operating Company NNEE_ _ __ _ _

South TwsPqcd Ekdrc avnSbtaion £0.

PO A289 MIhdwv Tcas 77483 W-V>E-0308l70 10CFR50.36 U. S. Nuclear Regulatory Commission Attention: Document Control Desk One White Flint North 11555 Rockville Pike Rockville, MID 20852 South Texas Project Unit 1 Docket No. STN 50-498 Unit 1 Cycle 12 Core Operating Limits Report. Revision 1 In accordance with Technical Specification 6.9.1.6.d, the attached Revision I to the Unit 1 Cycle 12 Core Operating limits Report is submitted for South Texas Project. This report reflects core design changes made during the Bottom Mounted Instrumentation (BMI) outage.

If there are any questions concerning this report, please contact Scott Head at (361) 972-7136 or me at (361) 972-7795.

David A. Leazar Director, Nuclear Fuel & Analysis kaw

Attachment:

Unit 1 Cycle 12 Core Operating Limits Report, Revision 1

&XIS:

< O~~:\Wp\NI\Nrc-ap\Misc-03\03001570.doc STI: 31635296

NOC-AE-03001570 Page 2 cc:

(paper copy) (electronic copy)

Ellis W. Merschoff A. H. Gutterman, Esquire Regional Administrator, Region IV Morgan, Lewis & Bockius LLP U.S. Nuclear Regulatory Commission 611 Ryan Plaza Drive, Suite 400 L. D. Blaylock Arlington, Texas 76011-8064 City Public Service U. S. Nuclear Regulatory Commission Mohan C. Thadani Attention: Document Control Desk U. S. Nuclear Regulatory Commission One White Flint North 11555 Rockville Pike R. L. Balcom Rockville, MD 20852 Texas Genco, LP Richard A. Ratliff A. Ramirez Bureau of Radiation Control City of Austin Texas Department of Health 1100 West 49th Street C. A. Johnson Austin, TX 78756-3189 AEP Texas Central Company Jeffrey Cruz Jon C. Wood U. S. Nuclear Regulatory Commission Matthews & Branscomb P. O. Box 289, Mail Code: MN1 16 Wadsworth, TX 77483 C. M. Canady City of Austin Electric Utility Department 721 Barton Springs Road Austin, TX 78704

Nuclear Operating Com pany M A-SOUTH TEXAS PROJECT UNIT 1 CYCLE 12 CORE OPERATING LIMITS REPORT Revision I July 2003 1

SOUTH TEXAS UNr I CYCLE 12 REv. I JULY2003 1.0 CORE OPERATING LIMITS REPORT This Core Operating Limits Report for STPEGS Unit I Cycle 12 has been prepared in accordance with the requirements of Technical Specification 6.9.1.6. The core operating limits have been developed using the NRC-approved methodologies specified in Technical Specification 6.9.1.6.

The Technical Specifications affected by this report are:

1) 2.1 SAFETY LIMITS

2) 2.2 LIMITING SAFETY SYSTEM SETTINGS

3) 3/4.1.1.1 SHUTDOWN MARGIN

4) 3/4.1.1.3 MODERATOR TEMPERATURE COEFFICIENT LIMITS

5) 3/4.1.3.5 SHUTDOWN ROD INSERTION LIMITS

6) 3/4.1.3.6 CONTROL ROD INSERTION LIMITS

7) 3/4.2.1 AFD LIMITS

8) 3/4.2.2 HEAT FLUX HOT CHANNEL FACTOR

9) 3/4.2.3 NUCLEAR ENTHALPY RISE HOT CHANNEL FACTOR

10) 3/4.2.5 DNB PARAMETERS 2.0 OPERATING LIMITS The cycle-specific parameter limits for the specifications listed in Section 1.0 are presented below.

2.1 SAFETY LIMITS (Specification 2.1):

2.1.1 The combination of THERMAL POWER, pressurizer pressure, and the highest operating loop coolant temperature (Tavg) shall not exceed the limits shown in Figure 1.

2.2 LIMITING SAFETY SYSTEM SETTINGS (Specification 2.2):

2.2.1 The Loop design flow for Reactor Coolant Flow-Low is 98,000 gpm.

2.2.2 The Over-temperature AT and Over-power AT setpoint parameter values are listed below:

Core Operating Limits Report Page 2

iW- Beliz SOUTrH TEXAS UNIT I CYCLE 12 REV. 1 JULY2003 Over-temperature AT Setnoint Parameter Values Ti measured reactor vessel AT lead/lag time constant, 'l = 8 sec T2 measured reactor vessel AT lead/lag time constant, 12 = 3 sec T3 measured reactor vessel AT lag time constant, r3 = 0 sec T4 measured reactor vessel average temperature lead/lag time constant, T4 = 28 sec T5 measured reactor vessel average temperature lead/lag time constant, 5 = 4 sec

'6 measured reactor vessel average temperature lag time constant, T6 = 0 sec K1 Overtemperature AT reactor trip setpoint, K1 = 1.14 K2 Overtemperature AT reactor trip setpoint Tavg coefficient, K2 = 0.028/ 0F K3 Overtemperature AT reactor trip setpoint pressure coefficient, K3 = 0.00143/psig T' Nominal full power Tavg, TI s 592.0 IF P' Nominal RCS pressure, P' = 2235 psig f,(AI) is a function of the indicated difference between top and bottom detectors of the power-range neutron ion chambers; with gains to be selected based on measured instrument response during plant startup tests such that:

(1) For q, - qb between -70% and +8%, f 1(Al) = 0, where q, and qb are percent RATED THERMAL POWER in the top and bottom halves of the core respectively, and q, + q%is total THERMAL POWER in percent of RATED THERMAL POWER; (2) For each percent that the magnitude of q, - qb exceeds -70%, the AT Trip Setpoint shall be automatically reduced by 0.0% of its value at RATED THERMAL POWER.

(3) For each percent that the magnitude of q, - qb exceeds +8%, the AT Trip Setpoint shall be automatically reduced by 2.65% of its value at RATED THERMAL POWER.

Over-power AT Setpoint Parameter Values tl measured reactor vessel AT lead/lag time constant, T = 8 sec T2 measured reactor vessel AT lead/lag time constant, tr2 = 3 sec t3 measured reactor vessel AT lag time constant, r3 = 0 sec T6 measured reactor vessel average temperature lag time constant, S6 = 0 sec T7 Time constant utilized in the rate-lag compensator for Tavg, t7 = 10 sec K4 Overpower AT reactor trip setpoint, K4 = 1.08 K5 Overpower AT reactor trip setpoint Tavg rate/lag coefficient, Ks = 0.02/1F for increasing average temperature, and Ks = 0 for decreasing average temperature K6 Overpower AT reactor trip setpoint Tavg heatup coefficient K6 = 0.002/F for T > T" and, K6 = 0 for T < T' T" Indicated full power Tavg, T" S 592.0 IF f 2(W) = 0 forall (Al) 2.3 SHUTDOWN MARGIN (Specification 3.1.1.1):

The SHUTDOWN MARGIN shall be:

2.3.1 Greater than 1.3% Ap for MODES 1 and 2*

• See Special Test Exception 3.10.1 2.3.2 Greater than the limits in Figure 2 for MODES 3 and 4.

2.3.3 Greater than the limits in Figure 3 for MODE 5.

Core Operating Limits Report Page 3

JULY2003 N N SOUTH TEXAS UNIT 1 CYCLE 12 REv. 1 JuLY2003 2.4 MODERATOR TEMPERATURE COEFFICIENT (Specification 3.1.1.3):

2.4.1 The BOL, ARO, MTC shall be less positive than the limits shown in Figure 4.

2.4.2 The EOL, ARO, HFP, MTC shall be less negative than -62.72 pcm/PF.

2.4.3 The 300 ppm, ARO, HFP, MTC shall be less negative than -53.72 pcm/0 F (300 ppm Surveillance Limit).

Where: BOL stands for Beginning-of-Cycle Life, EOL stands for End-of-Cycle Life, ARO stands for All Rods Out, HFP stands for Hot Full Power (100% RATED THERMAL POWER),

HFP vessel average temperature is 592 'F.

2.4.4 The Revised Predicted near-EOL 300 ppm MTC shall be calculated using the algorithm from T.S. 6.9.1.6.b.10:

Revised Predicted MTC = Predicted MTC + AFD Correction - 3 pcmPF If the Revised Predicted MTC is less negative than the S.R. 4.1.1.3b limit and all of the benchmark data contained in the surveillance procedure are met, then an MTC measurement in accordance with S.R. 4.1.1.3b is not required.

2.5 ROD INSERTION LIMTS (Specification 3.13.5 and 3.13.6):

2.5.1 All banks shall have the same Full Out Position (FOP) of at least 249 steps withdrawn but not exceeding 259 steps withdrawn.

2.5.2 The Control Banks shall be limited in physical insertion as specified in Figure 5.

2.5.3 Individual Shutdown bank rods are fully withdrawn when the Bank Demand Indication is at the FOP and the Rod Group Height Limiting Condition for Operation is satisfied (T.S. 3.1.3.1).

2.6 AXIAL FLUX DIFFERENCE (Specification 3.2.1):

2.6.1 AFD limits as required by Technical Specification 3.2.1 are determined by CAOC Operations with an AFD target band of +5, -10%.

2.6.2 The AFD shall be maintained within the ACCEPTABLE OPERATION portion of Figure 6, as required by Technical Specifications.

2.7 HEAT FLUX HOT CHANNEL FACTOR (Specification 3.2.2):

2.7.1 FPe = 2.55.

2.7.2 K(Z) is provided in Figure 7.

2.7.3 The FXy limits for RATED THERMAL POWER (wr) within specific core planes shall be:

2.7.3.1 Less than or equal to 1.903 for cycle burnups less than or equal to 10500 MWD/MTU, and less than or equal to 2.102 for cycle burnups greater than 10500 MWDIMTU, for all core planes containing Bank "DE control rods, and 2.7.3.2 Less than or equal to the appropriate core height-dependent value from Table I for all unrodded core planes.

2.7.3.3 PFxy = 0.2.

Core Operating Limits Report Page 4

SouTH TEXAS UNIT I CYCLE 12 REV. 1 JULY 2003 These F., limits were used to confirm that the heat flux hot channel factor F,(Z) will be limited by Technical Specification 3.2.2 assuming the most-limiting axial power distributions expected to result for the insertion and removal of Control Banks C and D during operation, including the accompanying variations in the axial xenon and power distributions, as described in WCAP-8385.

Therefore, these F.,, limits provide assurance that the initial conditions assumed in the LOCA analysis are met, along with the ECCS acceptance criteria of 10 CFR 50.46.

2.8 ENTHALPY RISE HOT CHANNEL FACTOR (Specification 3.2.3):

2.8.1 F,- = 1.5571 2.8.2 PFH = 0.3 2.9 DNB PARAMETERS (Specification 3.2.5):

2.9.1 The following DNB-related parameters shall be maintained within the following limits?

a. Reactor Coolant System Tavg' . 595 IF3,

b. Pressurizer Pressure, > 2200 psig4 ,

c. Minimum Measured Reactor Coolant System Flow 2 403,000 gpm5.

3.0 REFERENCES

3.1 Letter from T. D. Croyle (Westinghouse) to D. F. Hoppes (STPNOC), "Unit 1 Cycle 12 Redesign Final Unbound Reload Evaluation," NF-TG-03-76 (ST-UB-NOC-03002399), July 7,2003.

3.2 NUREG-1346, Technical Specifications, South Texas Project Unit Nos. 1 and 2.

3.3 STPNOC Calculation ZC-7035, Rev. 1, "Loop Uncertainty Calculation for RCS Tavg Instrumentation,"

October 19, 1998.

3.4 STPNOC Calculation ZC-7032, Rev. 3, "Loop Uncertainty Calculation for Narrow Range Pressurizer Pressure Monitoring Instrumentation," June 27,2001.

Applies to all fuel in the Unit 1Cycle 12 core.

2 A discussion of the processes to be used to take these readings is provided in the basis for Technical Specification 3.2.5.

3 Includes a 1.9 IF measurement uncertainty per Reference 3.3.

4 Limit not applicable during either a Thermal Power ramp in excess of 5% of RTP per minute or a Thermal Power step in excess of 10% RTP. Includes a 10.7 psi measurement uncertainty as read on the QDPS display per Reference 3.4.

Includes a 2.8% flow measurement uncertainty.

Core Operating Limits Report Page 5

E-;!'" SouTH TExAs UNIT I CYcLE 12 REV. I JULY2003 Figure 1 Reactor Core Safety Limits - Four Loops in Operation 680 660 640 v0 620 a600 580 560 540 0 20 40 60 80 100 120 140 Power (% RTP)

Core Operating Limits Report Page 6

4 SouTH TExAs UNIT I CYcLE 12 REv. I JULY2003 Figure 2 Required Shutdown Margin for Modes 3 & 4 8.0 7.0 . . . . . . . . . . . . . . . . . . . . . . . .

6.0

.E Lx 5.0 0

C E V4.0

~~~1 x1,<T /

Or 3.0 I/

711 I I II cepta 2.0 I I I Ij I

/4 7

1.0 0.0 0

400 800 1200 1600 2000 2400 RCS Critical Boron Concentration (ppm)

(fbr ARI ninus nost reactive stuck rod)

Core Operating Limits Report Page 7

Q#ii~l SourH TEXAs UNIT 1 CYCLE 12 REv. 1 JULY 2003 Figure 3 Required Shutdown Margin for Mode 5 8.0 7.0 6.0 5.0 C3 4P-3.0 20 1.0 0.0 0 400 800 1200 1600 2000 2400 RCS Critical Boron Concentration (ppm)

(for ARI minus most reactive stuck rod)

Core Operating Limits Report Page 8

SOUTH TEXAS UNIT I CYCLE 12 REv. I JULY2003 Figure 4 MTC venus Power Level 7.0 6.0 5.0 E 4.0 4)

' 3.0 4) 0 E 2.0 as I 0.

E 1.0 CC S.

C cl

4) 0.0 V

-1.0

-2.0

-3.0 0 20 40 60 80 100 Power (% RTP)

Core Operating Limits Report Page 9

SOUTH TEXAS UNTr I CYCLE 12 REv. 1 JULY2003 Figure 5 Control Rod Insertion Limits* versus Power Level 260 1

I 240 220 200 180 c 160

.' 140 U) 0 c 120 3

0 X 100 80 60 40 20 0

0 10 20 30 40 50 60 70 80 90 100 Power (% RTP)

• Control Bank A is already withdrawn to the Full Out Position. Fully withdrawn region shall be the condition where shutdown and control banks are at a position within the interval of 249 and 259 steps withdrawn, inclusive.

Core Operating Limits Report Page IO

__V2~SOUTrH TExAs UNrr I CYcLE 12 REv. I JULY 2003 Figure 6 AFD Limits versus Rated Thermal Power 120 100 80

.04 j 60 40 20 0

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

Core Operating Limits Report Page I I

U-,R SOtUMH TEXAS UNIT I CYCLE 12 REV. 1 JULY2003 Figure 7 K(Z) - Normalized FQ(Z) versus Core Height 1.2 1.0 FZ

.8 0

IL tM .6 (U

la .4 zE

.2 0

0.0 7.0 14.0 Core Height (ft)

Core Operating Limits Report Page 12

&Mr0,p

. AJ :t SouTH TEXAS UNrr I CYCLE 12 REv. I JULY 2003 SouTh TExAs UNrr I CYCLE 12 REV. I JULY2003 Table 1 (Part 1 of 2)

Unrodded F1 y for Each Core Height For Cycle Burnups Less Than or Equal to 10500 MWD/MTU Core Height Axial Unrodded Core Height Axial Unrodded (Ft.) Point Fxy (Ft.) Point Fxy 14.0 1 4.122 6.8 37 1.942 13.8 2 3.613 6.6 38 1.932 13.6 3 3.104 6.4 39 1.923 13.4 4 2.594 6.2 40 1.916 13.2 5 2.290 6.0 41 1.908 13.0 6 2.049 5.8 42 1.902 12.8 7 2.053 5.6 43 1.897 12.6 8 2.038 5.4 44 1.894 12.4 9 2.022 5.2 45 1.893 12.2 10 1.995 5.0 46 1.895 12.0 11 1.974 4.8 47 1.896 11.8 12 1.962 4.6 48 1.897 11.6 13 1.959 4.4 49 1.893 11.4 14 1.959 4.2 50 1.887 11.2 15 1.956 4.0 51 1.889 11.0 16 1.951 3.8 52 1.890 10.8 17 1.946 3.6 53 1.892 10.6 18 1.944 3.4 54 1.898 10.4 19 1.942 3.2 55 1.905 10.2 20 1.947 3.0 56 1.910 10.0 21 1.952 2.8 57 1.913 9.8 22 1.957 2.6 58 1.890 9.6 23 1.965 2.4 59 1.862 9.4 24 1.972 2.2 60 1.831 9.2 25 1.980 2.0 61 1.826 9.0 26 1.989 1.8 62 1.833 8.8 27 2.000 1.6 63 1.849 8.6 28 2.011 1.4 64 1.857 8.4 29 2.021 1.2 65 1.874 8.2 30 2.030 1.0 66 1.913 8.0 31 2.034 0.8 67 2.046 7.8 32 2.024 0.6 68 2.292 7.6 33 2.005 0.4 69 2.593 7.4 34 1.986 0.2 70 2.895 7.2 35 1.964 0.0 71 3.197 7.0 36 1.952 Core Operating Limits Report Page 13

SU 1 1 SOUTH TEXAS UNIT I CYCLE 12 R~EV. I JULY2003 Table 1 (Part 2 of 2)

Unrodded FXy for Each Core Height For Cydle Burnups Greater Than 10500 MWD/MTU Core Height Axial Unrodded Core Height Axial Unrodded (Ft.) Point Fxy (Ft) Point Fxy 1 l 14.0 4.784 6.8 37 2.137 13.8 2 4.133 6.6 38 2.131 13.6 3 3.481 6.4 39 2.117 13.4 4 2.829 6.2 40 2.103 13.2 '5 2.436 6.0 41 2.089 13.0 6 2.124 5.8 42 2.078 12.8 7 2.107 5.6 43 2.068 12.6 8 2.080 5.4 44 2.059 12.4 9 2.054 5.2 45 2.050 12.2 10 2.028 5.0 46 2.041 12.0 11 1.998 4.8 47 2.032 11.8 12 1.996 4.6 48 2.021 11.6 13 2.001 4.4 49 2.009 11.4 14 2.008 4.2 50 1.997 11.2 15 2.015 4.0 51 1.983 11.0 16 2.020 3.8 52 1.970 10.8 17 2.025 3.6 53 1.957 10.6 18 2.027 3.4 54 1.945 10.4 19 2.029 3.2 55 1.934 10.2 20 2.033 3.0 56 1.918 10.0 21 2.039 2.8 57 1.896 9.8 22 2.045 2.6 58 1.871 9.6 23 2.052 2.4 59 1.856 9.4 24 2.059 2.2 60 1.838 9.2 25 2.066 2.0 61 1.835 9.0 26 2.071 1.8 62 1.834 8.8 27 2.074 1.6 63 1.840 8.6 28 2.078 1.4 64 1.859 8.4 29 2.082 1.2 65 1.915 8.2 30 2.088 1.0 66 2.011 8.0 31 2.095 0.8 67 2.212 7.8 32 2.105 0.6 68 2.528 7.6 33 2.116 0.4 69 2.903 7A 34 2.127 0.2 70 3.277 7.2 35 2.136 0.0 71 3.651 7.0 36 2.139 Core Operating Limits Report Page 14