Text

Areva Np Inc. Report Document No. ANP-2858-001, Palisades SFP Region 1 Criticality Evaluation with Burnup Credit
	ML092450684
Person / Time
Site:	Palisades
Issue date:	08/31/2009
From:	; AREVA NP
To:	; Office of Nuclear Reactor Regulation
References
	20004-016 ANP-2858-001
	Download: ML092450684 (85)
	v • d • e

ATTACHMENT 4 AREVA NP Inc. Report Document No. ANP-2858-001 PALISADES SFP REGION 1 CRITICALITY EVALUATION WITH BURNUP CREDIT 84 pages follow

A 20004-016 (07/23/2009)

NON PROPRIETARY AREVA AREVA NP Inc.,

an AREVA and Siemens company Document No: ANP - 2858 - 001 Palisades SFP Region I Criticality Evaluation with Burnup Credit AREVA NP INC. NON PROPRIETARY Page 1

A AREVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit Record of Revision Revision Pages/Sections/

No. Date Paragraphs Changed Brief Description / Change Authorization 000 August 2009 all Original Release 001 August 2009 re-issue complete document Incorporated Entergy Comments Page 2

A AR EVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit Table of Contents Page RECO RD O F REVISIO N .......................................................................................................................... 2 LIST O F TABLES ..................................................................................................................................... 5 LIST O F FIG URES ................................................................................................................................... 7 1.0 EXECUTIVE SUM MARY ......................................................................................................... 8 2.0 INTRO DUCTIO N........................................................................................................................... 8 3.0 ANALYTICAL METHO DS ....................................................................................................... 9 3.1 Com puter Program s and Standards ............................................................................ 9, 3.2 Analytical Requirem ents and Assum ptions ................................................................ 10 3.3 Com putational Models and Methods .......................................................................... 11 3.3.1 Bounding Fuel Assem bly Description ...................................................... 11 3.3.2 Region 1 Rack Data ................................................................................... 12 3.3.3 Material Specification ................................................................................ 15 3.3.4 Models for Degradation of Carborundum Plates ...................................... 15 3.3.5 Swelling Model ........................................................................................... 15 3.4 Analytical Model Conservatism s ................................................................................ 18 3.5 Tolerances, Penalties, Biases, and Uncertainties ........................................................ 18 3.5.1 Method Discussion of Tolerances, Biases, and Uncertainties ................... 18 3.5.2 System and Tolerance Effects .................................................................. 19 3.5.3 System and Tolerance Results ................................................................ 20 3.5.4 Sum m ary of Bias and Uncertainty Values ................................................ 22 4.0 RACK ANALYSIS ........................................................................................................................ 22 4.1 Region 1B (3-of-4 Configuration) ................................................................................ 23 4.1.1 Misload Conditions ..................................................................................... 25 4.1.2 Conservatism s ........................................................................................... 25 4.2 Region 1C (4-of-4 Configuration) ................................................................................ 25 4.2.1 Misload Conditions ..................................................................................... 27 4.2.2 Conservatism s ......................................................................................... 27 4.3 Region 1 E (4-of-4 Configuration) ................................................................................ 27 4.3.1 Misload Conditions ..................................................................................... 29 Page 3

A AR EVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit Table of Contents (continued)

Page 4 .3.2 C onservatism s .......................................................................................... 29 4.4 Non-Fuel Bearing Components (NFBC) ..................................................................... 29 4 .4.1 M isload C onditions .................................................................................... 30 4 .5 R a ck Inte ra ctio ns ............................................................................................................. 31 4.5.1 Regions 1A, 1B, and 1C Interaction Effects Results ................................. 31 4.5.2 Regions 1B and lC with Region 2 Interaction Effects Results .................. 33 4.5.3 Region 1 E and Region 2 Racks Interaction Effects Results ..................... 34 5.0

SUMMARY

AND CONCLUSIONS .......................................................................................... 35 6.0 LICENSING REQ UIREM ENTS .............................................................................................. 35 7 .0 R E F E R E N C E S ............................................................................................. ............................... 38 APPENDIX A: KENO-V.A BIAS AND BIAS UNCERTAINTY ........................................................................... 40 APPENDIX B: CASMO CALCULATIONS FOR BURNUP ............................................................................... 54 APPENDIX C: KENO.V-A TOLERANCE CALCULATIONS ............................................................................ 61 APPENDIX D: SPACER GRID, FUEL ROD, AND GUIDE BAR EFFECTS ...................................................... 69 APPENDIX E: RACK C AND E KENO-V.A INPUT DECKS AND CASMO-3 DEPLETION INPUT DECK ..... 73 Page 4

A AR EVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit List of Tables Page TABLE 3-1: BATCH Xl DIMENSIONS AND TOLERANCES ............................................................ 11 TABLE 3-2: DIMENSIONS OF PALISADES REGION 1 RACKS ...................................................... 12 TABLE 3-3: 'C' NOMINAL RACK WITH BIAS/UNCERTAINTIES .................................................... 21 TABLE 3-4: 'E' NOMINAL RACK 4-OF-4 WITH BIAS/UNCERTAINTIES ......................................... 21 TABLE 3-5: K95/95 DETERMINATION BASED UPON CALCULATED BIAS/UNCERTAINTY ........... 22 TABLE 3-6: 5% DEPLETION REACTIVITY UNCERTAINTY ................................... 22 TABLE 4-1: REGION 1B (3-OF-4 LOADING) REQUIREMENTS .................................................... 24 TABLE 4-2: REGION 1B K95/95 DETERMINATION FOR BORON DILUTION ................................... 24 TABLE 4-3: REGION 1B K95/95 DETERMINATION FOR MISLOAD CONDITIONS .......................... 25 TABLE 4-4: REGION 1C (4-OF-4 LOADING) REQUIREMENTS ..................................................... 26 TABLE 4-5: REGION 1C K95195 DETERMINATION FOR BORON DILUTION ................................... 26 TABLE 4-6: REGION 1C K95/95 DETERMINATION FOR MISLOAD CONDITIONS .......................... 27 TABLE 4-7: E-RACK REQ UIREM ENTS .......................................................................................... 28 TABLE 4-8: REGION 1E K95/95 DETERMINATION FOR BORON DILUTION ................................... 28 TABLE 4-9: REGION 1E K95/95 DETERMINATION FOR MISLOAD CONDITIONS .......................... 29 TABLE 4-10: NFBC REACTIVITY EVALUATION FOR 3-OF-4 BUC RACK ..................................... 30 TABLE 4-11: NFBC REACTIVITY EVALUATION FOR 4-OF-4 BUC RACK ..................................... 30 TABLE 4-12: INTERACTION RESULTS FOR REGIONS 1A, 1B, AND 1C RACKS ......................... 33 TABLE 4-13: INTERACTION RESULTS FOR REGIONS 1B AND 1C TO REGION 2 RACKS ...... 34 TABLE 4-14: INTERACTION RESULTS FOR REGION 1E AND REGION 2 RACKS ..................... 34 TABLE A-1: RANGE OF VALUES OF KEY PARAMETERS IN SPENT FUEL POOL ...................... 41 TABLE A-2: DESCRIPTIONS OF THE CRITICAL BENCHMARK EXPERIMENTS .......................... 42 TABLE A-3: RESULTS FOR THE SELECTED BENCHMARK EXPERIMENTS ............................... 45 TABLE A-4: TRENDING PARAM ETERS .......................................................................................... 47 TABLE A-5:

SUMMARY

OF TRENDING ANALYSIS ....................................................................... 49 TABLE A-6: RANGE OF VALUES OF KEY PARAMETERS IN BENCHMARK EXPERIMENTS .......... 53 TABLE B-i: DEPLETION MODELING CONSIDERATIONS ............................................................ 54 TABLE B-2: AXIAL MODERATOR TEMPERATURE DISTRIBUTION .............................................. 56 Page 5

A AR EVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit List of Tables (continued)

Page TABLE B-3: 15 AND 30 GWD/MTU BURNUP PROFILES - 336.81 CM HEIGHT ........................... 57 TABLE C-1: RA CK C VO IDING EFFECTS ...................................................................................... 61 TABLE C-2: FABRICATED BOX MODEL DIMENSIONS ................................................................. 62 TABLE C-3: INTER-BOX M ODEL DIM ENSIONS .............................................................................. 62 TABLE C-4: RACK 'C' NOMINAL TOLERANCE RESULTS ............................................................. 66 TABLE C-5: RACK 'E' NOMINAL TOLERANCE RESULTS ............................................................. 67 TABLE C-6: 'C' RACK NOMINAL FUEL TOLERANCES ................................................................. 67 TABLE C-7: 'E' RACK NOMINAL FUEL TOLERANCES ................................................................... 68 TABLE D-1: SPAC ER G R ID R ESU LTS ............................................................................................ 70 Page 6

A AREVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit List of Figures Page FIGURE 2-1: PALISADES FUEL STORAGE AREAS ............................... ......................................... 8 FIGURE 3-1: SKETCH OF MODEL OF 'C' RACK ............................................................................ 13 FIGURE 3-2: SKETCH OF MODEL OF 'E' RACK ........................................................................... 14 FIGURE 3-3: PHOTOGRAPH OF DISTORTED PLATE ................................................................... 16 FIGURE 3-4: FU EL SW ELLIN G MO D EL ........................................................................................... 17 FIGURE 4-1: REGION 1 B ADJACENT TO REGION 1A ................................................................... 32 FIGURE 4-2: REGION 1B ADJACENT TO REGION 1C ................................................................... 32 FIGURE 4-3: REGION 1C ADJACENT TO REGION 1A ................................................................... 33 FIGURE 6-1: FUEL LOADING PATTERN FOR REGION 1B ........................................................... 35 FIGURE A-1: DISTRIBUTION OF KEFF DATA VERSUS EALF FOR THE SELECTED POOL OF BENCHMARK EXPERIM ENTS ................................................................................. 49 235 FIGURE A-2: DISTRIBUTION OF KEFF DATA VERSUS ENRICHMENT ( U) FOR THE SELECTED POOL OF BENCHMARK EXPERIMENTS ................................................................ 50 FIGURE A-3: DISTRIBUTION OF KEFF DATA VERSUS H/X FOR THE SELECTED POOL OF BENCHMARK EXPERIM ENTS ................................................................................. 50 FIGURE A-4: DISTRIBUTION OF KEFF DATA VERSUS SOLUBLE BORON CONCENTRATION FOR THE SELECTED POOL OF BENCHMARK EXPERIMENTS ...................................... 51 FIGURE A-5: PLOT OF STANDARD RESIDUALS FOR REGRESSION ANALYSIS WITH EALF AS TR EN D IN G PA RA M ETER .......................................................................................... 51 FIGURE A-6: PLOT OF STANDARD RESIDUALS FOR REGRESSION ANALYSIS WITH ENRICHMENT AS TRENDING PARAMETER .......................................................... 52 FIGURE B-i: BURNUP PROFILES FOR CYCLES 18-21 FOR BURNUPS 30-34 GWD/MTU ...... 58 FIGURE C-1: SKETCH OF KENO-V.A MODEL AT EDGE OF REGION 2 RACKS .......................... 63 FIGURE C-2: SKETCH OF A PORTION OF THE 'C'-REGION 2 MODEL ........................................ 64 FIGURE C-3: SKETCH OF A PORTION OF THE REGION 1 E -REGION 2 MODEL ...................... 65 FIG URE D-1: SKETCH O F G UIDE BAR .......................................................................................... 72 Page 7

A AR EVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit 1.0 EXECUTIVE

SUMMARY

This report contains the criticality evaluation of the Palisades Spent Fuel Storage Racks for the Region 1 racks that contain Carborundum plates (Reference [1]) as a poison. There are indications of swelling and of boron loss through attenuation measurements. This evaluation assumes total boron loss from the Carborundum plates, bumup credit, and a swelling model. The same soluble boron credit that was used in Region 2 is assumed for the Region 1 evaluations. Rack interaction effects are evaluated and found to be acceptable.

2.0 INTRODUCTION

The Palisades Nuclear Plant (PNP) requires a criticality analysis to address the Spent Fuel Storage Racks (SFSR) that are currently designated as Region 1 and contain Carborundum boron carbide (B4C) neutron absorbing plates that are degraded. These fuel storage locations at Palisades are shown in Figure 2-1.

Figure 2-1: Palisades Fuel Storage Areas 47 48 49 50 s5 52 53 54 5S 56 57 559 40 61 62 63 64l65 66 67 U69 AW -111-1:1001-10 TRNSF" EO ~ lI 4f* f Til T-O PNdl 1i E ID MECHANISMRegion 2 cr-1] EEIDi Region]2 1 34 67 9 10 11 1 11 14 1 1 17 16 19 20 21 22 23 24 1 2S 26 21 28 29 3031 32 3 13 4 15 6 37 38 39 D 41 4: 43 44 t46 45 F-I-FIIq F-IE I=00000 FI-IE RF-iF-1F-FIF-1I-EE]EiE]EI-IIIt-II-E]I-I-EII-EI-i rn00OODDr0000E IODDDDDDDDD E]EDDI IK III IIIIw 11W1121 INIF1II

.oI o o oooLW" SElCE K E - m F n

)F~ Region2MiSpet S-17 PLATFORM e. Fu a oIel o L W F-17 7-[]D]f[JEnE)):]FEE

].... 'o eio .. ot S1Ie i-qF-1t- Ir--EII-IEI- IE]r-IEI- Ir IE F-r10 . PIN.

oO000OWDWDOOOnC WWWWWIEODEW i NUCLEA PTW 70 "N172 73 74 75 ?6 T7 7EW79 0 81 82 8 DWWW DWWU 84 85 86 87 88 8g 90 WW 91 92 93 FEL W

SATU WESTINGHOUSE CREDIT FOR BUCRIUP WA.CKW

, F D ET100 0 O F1O310 11 0 0 O0 0,.s 0E10 13EE0 El PLSDES NUCLEARPLANT]

ZO00]-IIDDDI-]F]OO OO O O FI[3BO0000O- FUEL STATUSI NEW FUELSTORAGERACK CAS;KWASHIDOWN Page 8

A AR EVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit This study determines the maximum K-effective (k~f) of different regions for the effects associated with fuel storage in the Palisades Region 1 Spent Fuel Storage racks relative to a conservative treatment of the degradation of the Carborundum plates. The four regions are:

1) Region 1A - Region 1 Main Spent Fuel Pool with checkerboard loading of fuel with empty cells for fuel having nominal planar average U-235 enrichments less than or equal to 4.54 weight percent with no burnup credit.

2) Region IB - Region 1 Main Spent Fuel Pool with 3-of-4 loading having nominal planar average U-235 enrichments less than or equal to 4.54 weight percent and bumup credit as shown in Table 4-1.

3) Region 1C - Region 1 Main Spent Fuel Pool with 4-of-4 loading having nominal planar average U-235 enrichments less than or equal to 4.54 weight percent and bumup credit as shown in Table 4-4.

4) Region lE - Region 1 North Tilt Pit with 4-of-4 loading having nominal planar average U-235 enrichments less than or equal to 4.54 weight percent and burnup credit as shown in Table 4-7.

This report includes the bumup credit analysis for only Regions 1B, IC, and 1E and, for the three regions, defines the acceptable geometries, and demonstrates that the reactivity effects of the rack and fuel assembly manufacturing tolerances, the reactivity effects of pool moderator temperature variations, swelling in the poison plates, complete loss of the absorber material contained within the walls, and accident conditions are acceptable. The analyses for Region 1A and Region 2 that were approved in Reference [2] and [3], respectively, remain valid.

Criticality results and Licensing Requirements are summarized in Sections 5.0 and 6.0, respectively.

3.0 ANALYTICAL METHODS The analytical methods are discussed in this section. It briefly describes computer programs, licensing requirements, and computer models used for this analysis.

3.1 Computer Programs and Standards The KENO-V.a computer code (Reference [4]), a part of the SCALE 4.4a package, was used to calculate the kcff of 100 critical systems (criticality benchmark experiments). The 44 group cross section set 44GROUPNDF5 was used by the SCALE driver module CSAS25, which used modules BONAMI-2 and NITAWL to perform spatial and energy self-shielding of the cross sections for use in KENO-V.a. While

'holes' were used in the geometry models, they were modeled to preclude the error described in NRC Information Notice 2005-13, "Potential Non-conservative Error in Modeling Geometric Regions in the KENO-V.A Criticality Code," May 17, 2005.

The CASMO-3 computer code (Reference [5]), a multi-group two dimensional transport theory program was used to calculate burmup for the assemblies. CASMO-3 is primarily a cross section generator with depletion capability. The code handles a geometry consisting of cylindrical fuel rods of varying compositions in a square pitch array. Typical fuel storage rack geometries can also be handled.

Page 9

A AR EVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit 3.2 Analytical Requirements and Assumptions The purpose of the spent fuel storage racks is to maintain the fresh and irradiated assemblies in a safe storage condition. The current licensing basis as defined by the existing Technical Specification Requirements and federal code requirements, 10 CFR 50.68(b), specifies the normal and accident parameters associated with maintaining the fresh and irradiated assemblies in a safe storage condition. 10 CFR 50.68(b) defines the criticality accident requirements associated with the spent fuel racks and states the following: "If credit is taken for soluble boron, the k-effective of the spent fuel storage racks loaded with fuel of the maximum fuel assembly reactivity must not exceed 0.95, at a 95 percent probability, 95 percent confidence level, if flooded with borated water, and the k-effective must remain below 1.0 (subcritical) at a 95 percent probability, 95 percent confidence level, if flooded with unborated water."

The current analysis basis for Region 2 from Reference [6] is a maximum kcff of less than 1.0 when flooded with unborated water, and less than, or equal to 0.95 when flooded with water having a soluble boron concentration of 850 ppm. In addition, the klff in accident or abnormal operating conditions is less than 0.95 with 1350 ppm of soluble boron.

This analysis demonstrates that the effective neutron multiplication factor, keff, is less than 1.0 with the racks loaded with fuel of the highest anticipated reactivity, and flooded with un-borated. water at a temperature corresponding to the highest reactivity. In addition, the analysis demonstrates that kaf is less than or equal to 0.95 with the racks loaded with fuel of the highest anticipated reactivity, and flooded with borated water at a temperature corresponding to the highest reactivity. The maximum calculated kff included a margin for uncertainty in reactivity calculations including manufacturing tolerances and is shown to be less than 0.95 with a 95% probability at a 95% confidence level with soluble boron credit.

Reactivity effects of abnormal and accident conditions were also evaluated to assure that under all credible abnormal and accident conditions, the klff will not exceed the regulatory limit of 0.95 under borated conditions or a limit of 1.0 with unborated water. The double contingency principal of ANS-8.1/N 16.1-1975 (and the USNRC letter of April 1978; see fourth bullet below) specifies that it shall require at least two unlikely, independent and concurrent events before a criticality accident is possible.

This principle precludes the necessity of considering the simultaneous occurrence of multiple accident conditions.

Applicable codes, standard and regulations or pertinent sections thereof, include the following:

" Code of Federal Regulations, Title 10, Part 50, Appendix A, General Design Criterion 62, "Prevention of Criticality in Fuel Storage and Handling."

" Code of Federal Regulations, Title 10, Part 50.68(b), "Criticality Accident Requirements."

USNRC Standard Review Plan, NUREG-0800, Section 9. 1. 1, "Criticality Safety of Fresh and Spent Fuel Storage and Handling," Rev. 3 - March 2007.

USNRC letter of April 14, 1978, to all Power Reactor Licensees - OT Position for Review and Acceptance of Spent Fuel Storage and Handling Applications (GL-78-01 1), including modification letter dated January 18, 1979 (GL-79-004).

L. Kopp, "Guidance on the Regulatory Requirements for Criticality Analysis of Fuel Storage at Light-Water Reactor Power Plants," NRC Memorandum from L. Kopp to T. Collins, August 19, 1998. [7]

USNRC Regulatory Guide 1. 13, "Spent Fuel Storage Facility Design Basis," Rev. 2, March 2007.

Page 10

A AR EVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit

ANSI ANS-8.17-1984, "Criticality Safety Criteria for the Handling, Storage and Transportation of LWR Fuel Outside Reactors."

Code benchmarking was performed according to the general methodology described in Reference [8] that is also briefly described in Section A. 1. The critical experiments selected to benchmark the computer code system are discussed in Section A.3. The results of the criticality calculations, the trending analysis, the basis for the statistical technique chosen, the bias, and the bias uncertainty are presented in Sections A.4, A.5, and A.6.

3.3 Computational Models and Methods This section describes the basic models used to evaluate the three regions in the PNP SFSR. Results using these models are described in later sections.

3.3.1 Bounding Fuel Assembly Description Batch Xl with an initial nominal planar average enrichment of 4.54 wt% 2 3 5 "Uis used to bound the possible enrichments and different fuel types in the storage rack evaluations. Table 3-1 shows the dimensions of the bounding Xl model employed in this report. Reference [9]

provides a discussion of the appropriate biases to apply to bound the other assembly designs.

Some legacy fuel (e.g. Batches A-K) had lumped burnable absorber pins in empty tubes and/or had fuel rods replaced with either stainless steel rods or empty pin cells. Special consideration was given to these fuel assemblies in the burnup credit analysis. This is described in Section B.2. Fuel end details are not modeled. Fuel in the racks are modeled as surrounded by full (12 inches) water reflection at top and bottom. Reference [9] also shows that a zone loaded assembly has an equivalent or less reactivity than an assembly with a constant enrichment equal to the average of the assembly.

Table 3-1: Batch Xl Dimensions and Tolerances Parameter Nominal Tolerance Units in in Pitch 0.55 Pellet OD 0.3600 +/-0.0005 Clad ID 0.3670 +/-0.0015 Clad OD 0.417 +/-0.002

Guide Bars 8 Effective Area* 0.1586 in2

Instrument Tubes 1 IT ID 0.3670 +/-0.0015 ITOD 0.417 +0.002 Active Fuel 132.6 +0.29 Density, %TD 96%** +1.50%

Represents a conservatively small area for this parameter.

- A slightly higher percent theoretical density (TD) of 96% is used to bound the densities of other assemblies.

Page 11

A AREVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit 3.3.2 Region 1 Rack Data Region 1 of the Palisades spent fuel storage pool comprises two rack designs. The main region consists of six 'C' racks for storage of 372 fuel assemblies. Regions IA, 1B, and IC are rack type 'C'. Another rack, the 'E' rack is placed in the 'North Tilt Pit' and can hold 50 assemblies on a slightly wider pitch than the 'C' racks. Region lE is rack type 'E'. Table 3-2 lists the dimensions of the two racks. Figure 3-1 and Figure 3-2 provide sketches of each rack type, which illustrate the geometries used in KENO-V.a for each fuel cell. The actual comers of the box walls are rounded whereas the sketch is squared off. A single SS-304 separation rod of-0.25" OD is placed at each comer of the 'C' rack. A set of two similar SS-304 separation rods is placed before the rounded section of each comer of the 'E' rack. The fuel box in the rack is primarily SS-304, absorber material, and moderator. The standard SS-304 mixture of the SCALE composition library is used for this material. The moderator is water at 1.0 g/cc.

The current analysis in Reference [9] for the Region 1 rack assumed that the absorber plate was composed of only B 4 C with a reduction in the plate density due to the neglect of the phenol filler material. A carbon mass of 0.2720 g/cc was calculated for the reduced density plate. For this evaluation of Regions 1B, 1C, and lE the absorber material was assumed to be degraded as described in Section 3.3.4 which is the same as the absorber plate model in Reference [9].

Table 3-2: Dimensions of Palisades Region 1 Racks Region I Rack Type 'C' Rack 'E' Rack Dimension Nominal, in Tolerance, in Nominal, in Tolerance, in Cell Pitch-x 10.25 +0.04/-0.04 11.25 +0.04/-0.04 Cell Pitch-y 10.25 +0.04/-0.04 10.69 +0.04/-0.04 Box ID 8.56 +0.00/-0.12 9.00 +0.00/-0.12 Box OD 9.56 +0.12/-0.00 10.00 +0.12/-0.00 Box Wall Thickness, Inside 0.125 +0.010/-0.010 0.125 +0.010/-0.010 Box Wall Thickness, Outside 0.125 +0.010/-0.010 0.125 +0.010/-0.010 Absorber Thickness 0.210 +0.035/-0.02 0.210 +0.035/.-0.02 Absorber Width 8.26 +0.05/-0.010 8.26 +0.05/-0.010 Page 12

A AREVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit Figure 3-1: Sketch of Model of 'C' Rack Absoi 0.21 "

00000t000000*0000 000000000000O000 000000000000000 000000000000000 000000000000000 000 000 000 000 000 000000000000000 000000000000000 000000000000000 000000000000000 000000000000000 000000000000000

.... 00000000000 000000000000000

. ::. . . . . . . . . . . . . .. . . . . . . . . ::$:~. I;:

"=1 II 0.125 0.I2- II I I 0 5 8.56"

-* 41-0.25" 10.25" Page 13

A AREVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit Figure 3-2: Sketch of Model of 'E' Rack 7 7ý77 7 7 7ý7ý71111 7 7 7 7 7 7 7 7ý7

'd 11.25" Page 14

A AR EVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit 3.3.3 Material Specification The fuel materials include the uranium oxide pellets, the clad material, and the moderator surrounding the cladding. All materials in the base model are assumed to be at 293 K. The moderator for the base case is assumed to be unborated water with a density of 1.0 g/cc. The fuel pellets are assumed to have a 96% TD to correspond to the highest nominal density of past, current, or proposed pellets. No dish or chamfer is included in the density, thus the fuel column is conservatively modeled as a solid cylinder of fuel.

The cladding, instrument tubes, and guide bar are zirconium alloys. In the past these components were Zirc-4. Beginning with Batch Y (loaded in the Spring 2009 outage, and subsequent batches) M5 cladding is used for the fuel rods and the instrument tube. At some point in the future, M5 may be used for the spacer and guide bars. These components are assumed to be composed of pure zirconium. This approximation will be slightly conservative because the alloy additives (such as Tin and Niobium) generally have a higher capture cross section than Zr and thus tend to slightly reduce the assembly reactivity.

The fuel box in the rack is primarily SS-304, absorber material and moderator. The standard SS-304 mixture of the SCALE composition library is used for this material. The moderator is again water at 1.0 g/cc. The absorber material composition is based upon an assumption of the degraded condition of the B 4C absorber material.

3.3.4 Models for Degradation of Carborundum Plates Evidence of stuck assemblies and recent attenuation testing of the absorber plates in Region 1 has indicated a reduction in the absorption capability of the flux trap between the fuel locations in the Region 1 rack. A possible cause is leaching of boron from the B 4C absorber plates due to a combination of gamma irradiation of the phenol material and water in the absorber region of the box. An alternate, or complementary, cause of the loss of attenuation capability could be swelling of the box walls that reduce the moderator between the fuel assembly and the wall and between the walls of the flux trap. Either condition can reduce the effectiveness of the absorber plates. To bound the boron loss, the boron contained in the Carborundum plates is assumed to be zero. The poison plate is modeled with its original dimensions but containing only the carbon from the B4C with a density of 0.2720 g/cc. No other materials are assumed in the poison plate even though the Carborundum plate contains hydrogen, oxygen, and additional carbon. Complete loss of boron is unlikely since limited testing has shown the presence of attenuation larger than the complete absence of boron but less than the minimum design value. Credit for the remaining amount is not taken since the cause of degradation and the rate of degradation are not well characterized and the assumption of no boron avoids the more complex surveillance that would be required for the amount of poison credited in the Carborundum plates.

3.3.5 Swelling Model There is also evidence of swelling of the stainless steel wall next to the assembly cell that contains the Carborundum plates. The nature of the swelling is a central bulge (side to side) on one face of the fuel cell and is shown in Figure 3-3. It is not clear whether the bulge is full height.

Page 15

A AR EVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit Figure 3-3: Photograph of Distorted Plate The cause of this distortion is not understood, however the effect of moving the walls toward or away from the fuel requires examination. See Figure 3-4. Three different possible configurations were examined. In the first, the outer stainless steel wall is displaced to the outer edge of the rack cell. The second is where the stainless steel wall on the interior moves inward until it rests against the fuel pins, and the third is where movement of both walls occurs.

To model the three swelling configurations, bowing in the outer wall was modeled by relocating the stainless steel outer wall until it contacts the adjacent cell. The stainless steel was thinned to conserve mass. Water filled the area formerly occupied by the wall, so that the water mass is also conserved. Bowing in the inner wall was modeled by relocating the stainless steel inner wall to the edge of the row of fuel pins. The stainless steel was not thickened to conserve mass, so this is conservative as stainless steel is lost in this model. The third configuration is where both the inner and outer walls were bowed. The configuration with only the outer steel wall bowed outward is the most restrictive, and is used in subsequent KENO-V.a cases.

Page 16

A AR EVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit Figure 3-4: Fuel Swelling Model Spacer Rod Weld\

00@0@@@o@Qe@ @Go@

The space created by the wall movement is modeled as water. Voiding of the area created by wall movement is not considered to be likely because:

1. A 0.50" gap above each spacer rod provides a communication path between the four sides such that a vent hole on one wall vents all four sides of the fuel box. (See Section 3.3.2 for information on spacer rods.) Gas generated in absorber material will collect at the top of the fuel box, displacing water until the elevation of the vent hole is reached and the gas escapes through the vent. This layer of gas is nominally 0.25 inches and is above the active fuel.

2. The spacer rod is tack welded to the inner box and is not welded to the outer box (see Figure 3-4), so a vent path between the spacer rod and bends of the outer box already exists.

An additional vent path between the spacer rod and the inner box could be also expected if swelling of a box wall occurred.

3. The individual fuel boxes are formed into an 8 x 8 array by welding the fuel boxes to a grid of spacer bars. These spacer bars have four 0.88" diameter vent holes drilled in the grid assembly. Additionally, the rack assemblies are open on the sides. Any gas formed within Page 17

A AR EVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit the flux trap region between the fuel boxes would then collect as bubbles on the bottom of the upper spacer bars and migrate to a spacer bar vent hole or to the edge of the rack assembly and escape, thus water is free to flow through the rack and not trap air pockets.

3.4 Analytical Model Conservatisms This section lists the major conservatisms associated with this evaluation.

1) No credit is taken for intermediate spacer grids, or end fittings (see Appendix 1)).

2) No credit is taken for any boron in the Carborundum plates.

3) The maximum fuel enrichment tolerance of 0.05 wt% is considered in the tolerance evaluation.

4) All fuel box outer steel walls are assumed bowed outward and filled with water (no voiding), and

5) For the tolerance calculations, the four-of-four loading configuration bounds the three-of-four loading configuration as shown in Tables B- 12 and B- 13 of Reference [9].

3.5 Tolerances, Penalties, Biases, and Uncertainties This section describes the tolerances, penalties, uncertainties, and biases utilized in the analysis of Racks C (Regions 1B, and IC) and E (Region 1E). The penalties that pertain to the rack design tolerances and system parameters are discussed in detail in Appendix C. Additionally, the KENO-V.a bias with its associated uncertainty is discussed in Appendix A. The results of these sections are summarized in this subsection.

3.5.1 Method Discussion of Tolerances, Biases, and Uncertainties Criticality analysis methodology involves the computation of a base klff for -the Spent Fuel Storage Rack (SFSR) using a code such as KENO-V.a. A KENO-V.a code bias plus uncertainty on the bias is determined based on comparison to measured critical fuel configurations (i.e., critical benchmarks; see Appendix A) and is then applied to the base absolute kcff. The bias is not assembly specific but can be dependent on the type of fuel involved (U0 2 versus MOX for example) or on intervening absorber materials. Typically, a bias is determined using critical benchmark calculations that are appropriate for the type of rack and fuel being analyzed. There is an uncertainty component on the bias that is the result of both measured and calculated uncertainties associated with the critical configurations analyzed. The uncertainty on the bias may be statistically combined with other uncertainties as it is independent.

Reactivity penalties due to fuel and rack structural tolerances and other uncertainties are determined by difference calculations and applied to the base kff plus bias (See Appendix C).

When Monte-Carlo codes are used in difference calculations an answer is provided with an associated uncertainty and the uncertainty on the difference calculation must be considered at the 95/95 confidence level.

Page 18

A AR EVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit The K 95/9 5 for the evaluation is calculated using the following formulation:

K 9 5/95 = keff + biasm + Aksys + [C 2 (aYk 2 + Gm,-'

+

2

) + Ak 0 2+ o

-o2 + Ak~u, where, kcff = the KENO-V.a calculated result; biasm = the bias associated with the calculation methodology underpredicting the benchmarks; Aksys = summation of Ak values associated with the variation of system and base case modeling parameters, e.g. moderator temperature and geometry biases; C confidence multiplier based upon the number of benchmark cases; Cyk,am, Usys = standard deviation of the calculated kff, methodology bias,, and system Aksys; Aktoj. cycto = statistical combination and standard deviation of statistically independent Ak values due to manufacturing tolerances, e.g. fuel enrichment, cell pitch, etc.

AkBu = 5% depletion reactivity uncertainty for Bumup Credit cases 3.5.2 System and Tolerance Effects System and tolerance effects are calculated for several combinations of conditions. They include:

Four out of four fuel loading configurations.

Rack C (Regions lB and 1C) and Rack E configurations.

KENO-V.a is used for all the system and tolerance calculations. A two by two cell KENO-V.a model is used to calculate these effects.

3.5.2.1 System Effects The system effects are different conditions from the base model of the fuel and rack that could result in a higher calculated keff. These effects are considered additive unless otherwise noted.

The system effects are listed below.

1) Rack to Rack Interaction Model (see Section 4.5),

2) Non Fuel Bearing Components in the Empty Cells (see Section 4.4)

Page 19

A AR EVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit 3.5.2.2 Fuel and Rack Tolerance Effects The fuel and rack tolerances that are examined for the nominal (nonswollen) racks are listed below:

1) Centered to Off-Centered Assembly in Fuel Cell

2) Fuel Tolerance - Enrichment, +/-0.05 weight percent U-235

3) Fuel Tolerance - Theoretical Density, +/-1.5%

4) Fuel Tolerance - Pellet OD, +0.0005"

5) Fuel Tolerance - Clad Inner Dimension, +/-0.0015"

6) Fuel Tolerance - Clad Outer Dimension, +/-0.002"

7) Fuel Tolerance - Instrument Tube Dimension, ID, +/-0.0015"

8) Fuel Tolerance - Instrument Tube Dimension, OD, +/-0.002"

9) Rack Tolerance - Box Inner Dimension, -0.12"

10) Rack Tolerance - Inner Box Wall Thickness, +/-0.01"

11) Rack Tolerance - Absorber Thickness, +0.035/-0.02"

12) Rack Tolerance - Absorber Width, +0.05/-0.01"

13) Rack Tolerance - Outer Box Wall Thickness, +/-0.01"

14) Rack Tolerance - Box Outer Dimension, +0.12"

15) Rack Tolerance - Cell Pitch, +/-0.04"

16) Rack Tolerance -Stainless Steel Separation Rod, OD, +/-0.005" See Appendix D for the effect of fuel rod pitch tolerance 3.5.3 System and Tolerance Results Table 3-3 and Table 3-4 summarize the tolerance and uncertainty values obtained in the evaluation. Only positive bias/uncertainty values have been extracted from the various evaluations previously described, excluding values that are less than 0.0002, as they are within the bias of the code. Detailed results can be found in Appendix C. The additive biases are generally related to the rack configuration or environment that is defined in the equation as Aksys. The parameters related to randomly varying manufacturing tolerances for fuel and/or racks are statistically combined and defined in the equation as Ako01. In addition, the off-center placement is assumed to be a random parameter.

Page 20

A AREVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit Table 3-3: 'C' Nominal Rack with Bias/Uncertainties Description Ak g of Ak Storage Pool Model Configuration Bias Interaction Model I _ __

NFBC in empty cell of 3-of-4 for only 0 ppm 0.0013 0.0008 TOTAL (Arithmetic Sum of Penalties) 0.0013 0.0008 Tolerance Uncertainty Ak Assembly Not Centered In Rack 0.0036 0.0001 Fuel Tolerance - Enrichment +0.05 wt% 0.0022 0.0001 Fuel Tolerance - Theoretical Density +1.5% 0.0011 0.0001 Fuel Tolerance - Clad ID +0.0015" 0.0003 0.0001 Fuel Tolerance - Clad OD -0.002" 0.0017 0.0001 Fuel Tolerance - Pellet OD + 0.0005" 0.0002 0.0001 Rack Tolerance - Inner Box Wall Thickness Inside, -0.01 0.0024 0.0001 Rack Tolerance -Absorber Thickness +0.035 0.0103 0.0001 Rack Tolerance -Absorber Width +0.05 0.0003 0.0001 Rack Tolerance - Outer Box Wall Thickness Outside -0.01 0.0012 0.0001 Rack Tolerance -Pitch -0.04" 0.0066 0.0001 TOTAL (Statistical Combination of Uncertainties) 0.0134 0.0004 Table 3-4: 'E' Nominal Rack 4-of-4 with Bias/Uncertainties Description Ak a of Ak Storage Pool Model Configuration Bias Interaction Model I - -

TOTAL (Arithmetic Sum of Penalties) 0 0 Tolerance Uncertainty Ak Assembly Not Centered In Rack 0.0252 0.0003 Fuel Tolerance - Enrichment +0.05 wt% 0.0019 0.0003 Fuel Tolerance - Theoretical Density +1.5% 0.0012 0.000.3 Fuel Tolerance - Clad ID +0.00 15" 0.0007 0.000.3 Fuel Tolerance - Clad OD -0.002" 0.0022 0.0003 Rack Tolerance - Inner Box Wall Thickness Inside -0.01 0.0017 0.000:3 Rack Tolerance -Absorber Thickness +0.035 0.0074 0.0003 Rack Tolerance - Outer Box Wall Thickness Inside -0.01 0.0008 0.0003 Rack Tolerance -Pitch -0.04" 0.0050 0.0003 TOTAL (Statistical Combination of Uncertainties) 0.0270 0.0008 Page 21

A AR EVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit 3.5.4 Summary of Bias and Uncertainty Values Table 3-5 and Table 3-6 summarize the variables shown in the formula in Section 3.5.1 for each of the configurations examined.

Table 3-5: K95/95 Determination Based Upon Calculated Bias/Uncertainty biasm Aksy a m Aktol c of Ako1 Rack C 3-of-4 0.00542 0.0013* 0.0051 0.0134 0.0004 (Region 1B)

Rack C 4-of-4 0.00542 0 0.0051 0.0134 0.0004 (Region IC)

Rack E 4-of-4 0.00542 0 0.0051 0.0270 0.0008 (Region IE)

For 0 ppm only.

Table 3-6: 5% Depletion Reactivity Uncertainty Enrichment (wt %) GWD/MTU AkBU 3.2 15 0.0097 4.0 24 0.0132 4.54 15 0.0093 4.54 30 0.0150 4.0 RACK ANALYSIS In order to determine depletion and burnup credit, the same basic methodology as in Reference [10] was used. This methodology addresses the applicability of NUREG/CR-6801 (Reference [ 11]) for axial burnup profiles, the use of 5% reactivity decrement from 0 burnup to burnup of interest, and the use of CASMO-3 to generate the fuel assembly isotopic compositions at specified burnups. In addition, a large, 10%, additional burnup uncertainty allowance is added to the required fuel burnup limits to bound the measurement uncertainty. Appendix B presents the calculation of burnup credit.

The current analysis basis for Region 2 from Reference [6] is a maximum keff of less than 1.0 when flooded with unborated water, and less than or equal to 0.95 when flooded with water having a boron concentration of 850 ppm. In addition, the kcff in accident or abnormal operating conditions is less than 0.95 with 1350 ppm of soluble boron. This same basis is used for Region 1B, 1C, and 1E, and was also Page 22

A AR EVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit used in Reference [9] for Region IA. The following abnormal conditions are considered for Region 1B, IC, and 1E:

1. The deboration of the pool,

2. Misplacement of a fresh assembly within a cell that should be empty or replacement of a burnup credit (BUC) assembly,

3. Drop of a fuel assembly outside the rack but adjacent to the rack,

4. Off-center assembly (addressed in Section 3.5),

5. The 'straight deep drop' accident,

6. T-Bone drop accident, and

7. Rack interactions.

The deboration of the SFSR is considered the baseline case and the K 95 /9 5 is calculated at both 0 ppm boron and 850 ppm boron. All other abnormal conditions are evaluated at-1350 ppm boron. The misplacement of an assembly into an empty cell is referred to as a 'misload.' The misload is important to evaluate since empty cells are used to control reactivity. The misload condition bounds the drop outside the rack module because the misloaded assembly can increase the number of face adjacent fuel assemblies by at least four whereas outside the rack will at most be two face adjacent assemblies to the dropped assembly. The off-center assembly which is a horizontal movement of the assembly within the rack is included in the tolerance evaluation. The drop accident within an empty cell is represented by the misload condition. The T-Bone drop accident has an assembly lying on top of the rack structure and is effectively isolated from assemblies in the rack due to the distance provided by the end fittings and the rack height above the active fuel in the rack. Thus, the T-bone accident is bounded by the misloaded condition.

The analysis for each of the regions is presented in this section for the unborated and borated condition (boron dilution event). The assembly misload conditions are presented for the borated condition of 1350 ppm boron. In addition, non-fissile components are addressed relative to being placed into empty cells and rack interface effects are addressed.

4.1 Region 1B (3-of-4 Configuration)

Region lB is analyzed with soluble boron credit. The acceptance criteria with credit for soluble boron are K 9 5/95 <1.0 without soluble boron and <0.95 with 850 ppm of soluble boron. Region lB is defined as Main Spent Fuel Pool with 3-of-4 loading having nominal planar average U-235 enrichments less than or equal to 4.54 weight percent and bumup credit as shown in Table 4-1.

The results are presented in Table 4-2 for the Region lB geometry.

Page 23

A AR EVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit Table 4-1: Region 1B (3-of-4 Loading) Requirements nominal planar average > Burnup U-235 enrichment Burnup (GWD/MTU) (GWD/MTU) with (Wt%) 10% Uncertainty 2.50 0 0 2.60 0.74 0.81 2.80 2.21 2.43 3.00 3.68 4.05 3.20 5.15 5.67 3.40 6.62 7.28 3.60 8.09 8.90 3.80 9.56 10.52 4.00 11.03 12.13 4.20 12.50 13.75 4.40 13.97 15.37 4.54 15.00 16.50 Table 4-2: Region 1B K95/95 Determination for Boron Dilution Assembly Dissolved Enrichment Average Burnup, Boron, ppm kcff yk K 95/9 5 Criterion GWD/MTU 4.54 15 850 0.8423 0.0007 0.8737 _ 0.95 4.54 15 0 0.9339 0.0007 0.9667 < 1.0 2.50 0 850 0.8121 0.0007 0.8342 < 0.95 2.50 0 0 0.9368 0.0008 0.9603 < 1.0 Page 24

A AREVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit 4.1.1 Misload Conditions It is necessary to examine the accident condition of misloading a fresh assembly into the empty location in a '3-of-4' loading pattern. For this, it is assumed the fresh assembly has an enrichment of 4.54%. A soluble boron concentration of 1350 ppm is used. The fresh misloaded fuel assembly is placed into a position near the center of the matrix (8x8). The results are shown in Table 4-3.

Table 4-3: Region 1B K95/95 Determination for Misload Conditions Assembly Dissolved Enrichment Average Boron, lff Tk K 9 5/95 Criterion Burnup, ppm GWD/MTU 4.54 15 1350 0.8539 0.0008 0.8853 < 0.95 2.50 0 1350 0.8347 0.0009 0.8568 < 0.95 4.1.2 Conservatisms The major conservatisms are no boron in the poison plates, swollen geometry, and 1350 ppm boron rather than 1720 ppm minimum boron (a Technical Specification Requirement).

4.2 Region 1C (4-of-4 Configuration)

Region 1C is analyzed with soluble boron credit. The acceptance criteria with credit for soluble boron are K 95/9 5 <1.0 without soluble boron and <0.95 with 850 ppm of soluble boron. Region IC is defined as the Region I Main Spent Fuel Pool with 4-of-4 loading having nominal planar average U-235 enrichments less than or equal to 4.54 weight percent and burnup credit as shown in Table 4-4.

The results are presented in Table 4-5 for the Region 1C geometry.

Page 25

A AR EVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit Table 4-4: Region 1C (4-of-4 Loading) Requirements nominal planar average U-235 Burnup > Burnup (GWD/MTU) enrichment (GWD/MTU) with 10% Uncertainty (Wt%)

1.80 0 0 2.40 6.43 7.07 2.60 8.57 9.43 2.80 10.71 11.78 3.00 12.86 14.15 3.20 15.00 16.50 3.40 17.25 18.98 3.60 19.50 21.45 3.80 21.75 23.93 4.00 24.00 26.40 4.20 26.22 28.84 4.40 28.44 31.28 4.54 30.00 33.00 Table 4-5: Region 1C K95195 Determination for Boron Dilution Assembly Dissolved Enrichment Average Boron, keff Fk K95 /95 Criterion Burnup, ppm GWD/MTU 4.54 30 850 0.8369 0.0006 0.8740 _<0.95 4.54 30 0 0.9312 0.0006 0.9683 < 1.0 4.00 24 850 0.8329 0.0006 0.8682 < 0.95 4.00 24 0 0.9318 0.0007 0.9671 < 1.0 3.20 15 850 0.8427 0.0006 0.8745 < 0.95 3.20 15 0 0.9510 0.0007 0.9828 < 1.0 1.80 0 850 0.7967 0.0006 0.8188 <0.95 1.80 0 0 0.9413 0.0006 0.9634 <1.0 Page 26

A AREVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY

. Palisades SFP Region 1 Criticality Evaluation with Burnup Credit 4.2.1 Misload Conditions It is necessary to examine the accident condition of misloading a fresh assembly into a designated location in a 4-of-4 loading patterns. For this, it is assumed the fresh assembly has an enrichment of 4.54%. A soluble boron concentration of 1350 ppm is used. The fresh misloaded fuel assembly is placed into a position near the center of the matrix. The results are shown in Table 4-6.

Table 4-6: Region 1C K95/95 Determination for Misload Conditions Assembly Dissolved Enrichment Average Boron, keff Gk K95 /95 Criterion Burnup, ppm GWD/MTU 4.54 30 1350 0.8184 0.0009 0.8555 < 0.95 4.00 24 1350 0.8186 0.0008 0.8539 < 0.95 3.20 15 1350 0.8165 0.0008 0.8483

0.95 1.80 0 1350 0.7984 0.0009 0.8205 < 0.95 4.2.2 Conservatisms The major conservatisms are no boron in the poison plates, swollen geometry, and 1350 ppm boron rather than 1720 ppm minimum boron (a Technical Specification Requirement).

4.3 Region 1E (4-of-4 Configuration)

Region IE is analyzed with soluble boron credit. The acceptance criteria are K95/95 < 1.0 without soluble boron and < 0.95 with 850 ppm of soluble boron. Region 1E contains a five by ten rectangular array of cells with Region 2 racks placed on both ends of the rack as shown in Figure 2-1 in the North Tilt Pit.

Region 1E is defined as North Tilt Pit with 4-of-4 loading having a nominal planar average U-235 enrichments less than or equal to 4.54 weight percent and burnup credit as shown in Table 4-7.

The results are presented in Table 4-8 for Region 1E.

Page 27

A AR EVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit Table 4-7: E-Rack Requirements nominal planar average U-235 Burnup > Burnup (GWD/MTU) enrichment (GWD/MTU) with 10% Uncertainty (Wt%)

2.50 0 0 2.60 0.74 0.81 2.80 2.21 2.43 3.00 3.68 4.05 3.20 5.15 5.67 3.40 6.62 7.28 3.60 8.09 8.90 3.80 9.56 10.52 4.00 11.03 12.13 4.20 12.50 13.75 4.40 13.97 15.37 4.54 15.00 16.50 Table 4-8: Region 1E K95/ 95 Determination for Boron Dilution Assembly Dissolved Enrichment Average Boron, keff Ck K 95/95 Criterion Burnup, ppm GWD/MTU 4.54 15 850 0.8307 0.0006 0.8742 < 0.95 4.54 15 0 0.9345 0.0007 0.9780 < 1.0 2.50 0 850 0.8034 0.0007 0.8376 < 0.95 2.50 0 0 0.9380 0.0008 0.9722 < 1.0 Page 28

A AR EVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NO!N PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit 4.3.1 Misload Conditions It is necessary to examine the accident condition of misloading a fresh assembly into a designated location in a 4-of-4 loading patterns. For this, it is assumed the fresh assembly has an enrichment of 4.54%. A soluble boron concentration of 1350 ppm is used. The entire Region 1E is assumed to be misloaded with fresh 4.54 w/o assemblies. The results are shown in Table 4-9.

Table 4-9: Region 1E K95195 Determination for Misload Conditions Assembly Dissolved Enrichment Average Boron, keff Uk K95/95 Criterion Burnup, GWD/MTU ppm 4.54 0 1350 0. 8876 0.0007 0.9218 < 0.95 4.3.2 Conservatisms The major conservatisms are no boron in the poison plates, swollen geometry, all fresh fuel, and 1350 ppm boron rather than 1720 ppm minimum boron (a Technical Specification Requirement).

4.4 Non-Fuel Bearing Components (NFBC)

There are several NFBC that may potentially be inserted into the racks. Only Rack C is evaluated since it currently contains required empty cells. The four components are:

1. Heavy Test Assembly - A Standard Assembly with lead (Pb) pellets rather than U02,

2. Test Gauge Assembly - comprised of stainless steel angles and plates to allow testing the box inner dimension,

3. An assembly containing only SS-304 Replacement Rods (no fuel rods), and

4. Vessel Fluence Capsule and Carrier (bounded by a 5.48" square block of SS304 or square shell with the same mass, -522 Kg or 1100 lbs).

For the 3-of-4 BUC portion of the rack, the most reactive configuration is the fresh 2.50% enriched fuel at 0 ppm dissolved boron. Placement of NFBC is considered in both an open cell and as a replacement for a fuel assembly.

For the 4-of-4 BUC portion of the rack, the most reactive configuration examined for a 4-of-4 arrangement is the 3.20% enriched fuel at 15 GWD/MTU and 0 ppm dissolved boron. Placement of a NFBC is considered as a replacement for a fuel assembly. The results are shown in Table 4-10 and Table 4-11. The positive Ak of 0.0013 for Component 3 in empty cell versus Base Case shown in the 3-of-4 Rack is contained in the system tolerance Ak in Table 3-3.

Page 29

A AR EVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit Table 4-10: NFBC Reactivity Evaluation for 3-of-4 BUC Rack Description I kff Oyk BASE RACK 'C' 3-of-4 8x8 Array Model 0.9368 0.0008 Dummy Assembly Results Component I in empty cell 0.9377 0.0008 Component 1replacing assembly 0.9359 0.0007 Component 2 in empty cell 0.9360 0.0008 Component 2 replacing assembly 0.9353 0.0008 Component 3 in empty cell 0.9381 0.0007 Component 3 replacing assembly 0.9337 0.0007 Stainless Steel Block/Tubes Component 4 SS Square Shell in Water cell with 7.75" OD 0.9377 0.0008 and 5.48" ID in empty cell SS Square Shell in Water cell with 7.75" OD 0.9352 0.0007 and 5.48" ID replacing assembly Table 4-11: NFBC Reactivity Evaluation for 4-of-4 BUC Rack Description lkef Ok BASE RACK 'C' 4-of-4 8x8 Array Model 0.9510 0.0007 Dummy Assembly Results Component 1 replacing assembly 0.9471 0.0007 Component 2 replacing assembly 0.9482 0.0007 Component 3 replacing assembly 0.9488 0.0007 Stainless Steel Block/Tubes Component 4 SS Square Shell in Water cell with 7.75" OD and 5.48" ID 1 0.9481 0.0008 4.4.1 Misload Conditions A misloading of a NFBC (other than the heavy test assembly or the test gauge assembly) into a designated empty cell in Region 1A or lB that is within 10 cells of another NFBC (other than the heavy test assembly or the test gauge assembly) loaded into a designated empty cell, is bounded by a fuel misloading described in Section 4.1.1 above for Region lB. A fuel assembly is more reactive than an NFBC.

Page 30

A AR EVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens. company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit 4.5 Rack Interactions The interactions evaluated are:

between Region IA and Region 2 (This was analyzed in Reference [9], and is still valid).

between Region lB and lA.

between Region lB and IC.

" between Region IC and IA.

between Region lB and Region 2.

" between Region IC and Region 2.

" between Region IE and Region 2.

The detailed models to perform this study are defined and discussed in detail in Appendix C. 1.2. The swelling model is used for Regions IB, IC, and lE. Interaction between any two regions is examined by evaluating the two regions together. If k~ff increases above the maximum of either individual region, then there is an effect.

The fuel elevator and fuel inspection stations, which will handle fresh fuel, are located in a region adjacent to the C-rack. Fresh fuel assemblies at these stations are nominally water isolated from the rack due to distance. However, a fresh assembly may be inadvertently placed next to the C-rack. This would be bounded by either a misload described above or the interactions described below. Therefore, the presence of the fuel elevator and fuel inspection station does not cause additional restrictions to the acceptable fuel loading patterns.

4.5.1 Regions IA, 1B, and 1C Interaction Effects Results The interaction between the loading zones (2-of-4, 3-of-4, and 4-of-4) is examined.

The case with the highest value of kff from KENO-V.a for the 4-of-4 has an enrichment of 3.20% and a burnup of 15 GWD/MTU. For the 3-of-4 situation, it is fresh fuel with an enrichment of 2.50%. For 2-of-4 loadings, fresh fuel with a maximum enrichment of 4.54% is allowed. All cases were at 0 ppm dissolved boron. These situations are examined in various combinations. The 4-of-4 with 3-of-4 situation was examined in the empty cell of the 3-of-4 arrangement adjacent to the 4-of-4 region. The situation with the full row of the 3-of-4 adjacent to the 4-of-4 would not be allowed since it would create another 4-of-4 cluster that would have to comply with the 4-of-4 loading restrictions. (See Figure 4-1, Figure 4-2, and Figure 4-3)

As seen in Table 4-12, the boundary areas are not limiting, and that Region I.C is the limiting region.

Page 31

A AR EVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit Figure 4-1: Region 1B Adjacent to Region 1A U U U U U

U U U

iI Empty cell Region 1A (4.54% fresh fuel), 2-of-4 Region 1B (2.50% and a burnup of 0 GWD/MTU), 3-of-4 Figure 4-2: Region lB Adjacent to Region IC Empty cell Region 1B (2.50% and a burnup of 0 GWD/MTU), 3-of-4 Region 1C (3.20% and a burnup of 15 GWD/MTU), 4-of-4 Page 32

A AREVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit Figure 4-3: Region 1C Adjacent to Region 1A This configuration is not allowed as it creates a non-allowed 3-of-4 pattern.

This conservatively bounds the allowable pattern.

I I Empty cell Region 1A (4.54% fresh fuel), 2-of-4 Region 1C (3.20% and a burnup of 15 GWD/MTU), 4-of-4 Table 4-12: Interaction Results for Regions 1A, 1B, and 1C Racks Case Description k ff ak Base - Region 1B, 2.5%, 0 GWD/MTU 0.9368 0.0008 Base - Region IC, 3.2%, 15 GWD/MTU 0.9510 0.0006 Region lB adjacent to Region IA 0.9146 0.0009 Region IB adjacent to Region IC 0.9500 0.0009 Region IC adjacent to Region IA (4-of-4 next to 2-of-4) 0.9351 1.0007 4.5.2 Regions lB and 1C with Region 2 Interaction Effects Results The interaction between the loading zones (3-of-4 and 4-of-4 with Region 2) for both 0 ppm and 850 ppm soluble boron is examined. These situations are examined in various combinations. No additional restrictions on Regions lB or IC are necessary.

As seen in Table 4-13 the boundary areas are not limiting.

Page 33

A AR EVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit Table 4-13: Interaction Results for Regions 1B and 1C to Region 2 Racks Case Description Dissolved keff Cyk Boron, ppm Base- Region IB, 2.5%, 0 GWD/MTU 0 0.9368 0.0008 Base - Region IC, 3.2%, 15 GWD/MTU 0 0.9510 0.0007 Base - Region 2 0 0.9564 0.0002 Region lB adjacent to the Region 2 0 0.9563 0.0001 Region IC adjacent to the Region 2 0 0.9564 0.0001 Base- Region 1B, 4.54%, 15 GWD/MTU 850 0.8423 0.0007 Base - Region 1C, 3.2%, 15 GWD/MTU 850 0.8427 0.0006 Base - Region 2 850 0.7541 0.0002 Region 1B adjacent to the Region 2 850 0.8160 0.0001 Region IC adjacent to the Region 2 850 0.8007 0.0001 4.5.3 Region 1E and Region 2 Racks Interaction Effects Results The Region 1E is a five by ten array of cells reflected by 12" of water so that some effect is expected between Region 1E and the neighboring Region 2 racks. The same set of cases is modeled as for Region 1C and Region 2 except the minimum separation distances are modeled as 0.1", 3.33" and 10" to evaluate the impact of separation distances. Table 4-14 lists the results for the 'E' rack interaction evaluation at 0 and 850 ppm.

The first section examines the unborated condition and shows no interaction effects for the unborated condition, and that the Region 2 rack controls the combined reactivity. A small reactivity increase is seen for a 0.1" gap (from 0.9400 to 0.9432), which is significantly less than actual separation but is still significantly less than the base koff for a larger Region 2 model. The second set of cases in the table examines the interaction effects with 850 ppm soluble boron. No interaction effect is noted, but for 850 ppm the 'E' rack controls the combined reactivity. Therefore, no minimum separation distance between Region lE and Region 2 Racks is needed.

Table 4-14: Interaction Results for Region 1E and Region 2 Racks Case Description Boron, ppm keff ak Interaction Model, 0.1" Minimum Gap 0 0.9432 0.0003 Interaction Model, 3.33"Minimum Gap 0 0.9399 0.0003 Interaction Model, >10" Minimum Gap 0 0.9400 0.0003 Base - Region 2 Model 0 0.9564 0.0003 Base - Rack E Interaction Model 0 0.9409 0.0004 Case Description Boron, ppm kff Ok Interaction Model, 0.1" Minimum Gap 850 0.8017 0.0003 Interaction Model, 3.33"Minimum Gap 850 0.8016 0.0003 Interaction Model, >10" Minimum Gap 850 0.8015 0.0003 Base - Region 2 Model 850 0.7541 0.0002 Base - Rack E Interaction Model 850 0.8139 0.0003 Page 34

A AREVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit 5.0

SUMMARY

AND CONCLUSIONS This report documents the criticality safety analysis for the Palisades Region 1 fuel pool storage and shows that all requirements are met. The Region lB/lC/1E racks are analyzed to allow storage of fuel applying a burnup credit for a complete loss of boron in the Carborundum plates. More than 0.017 Ak margin to the respective criterion is calculated for the boron dilution events (both borated and unborated).

All abnormal conditions meet the 0.95 criterion at 1350 ppm of boron.

6.0 LICENSING REQUIREMENTS This analysis requires that the Technical Specifications for the Region 1 SFSR be modified to accommodate fuel in the manner defined by this document. Final wording of the Technical Specifications may differ from the wording presented here as long as the intent of the requirements remains the same.

The following requirements apply to Region 1.

1) Change the Region 1 definition to the following new regions a) Region 1A - Region 1 Main Spent Fuel Pool with checkerboard loading of fuel with empty or non-fuel bearing component cells for fuel having nominal planar average U-235 enrichments less than or equal to 4.54 weight percent. This region should not contain any face adjacent fuel.

b) Region 1B - Region 1 Main Spent Fuel Pool with 3-of-4 loading having nominal planar average U-235 enrichments less than or equal to 4.54 weight percent and meeting the requirements set forth in Table 4-1 (see Figure 6-1).

Figure 6-1: Fuel Loading Pattern for Region 1B

[ I il ..]

Empty cell

4.54 wt% U-235 Assembly Page 35

A AREVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company CNONPROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit c) Region IC - Region 1 Main Spent Fuel Pool with 4-of-4 loading with no required empty cells, having nominal planar average U-235 enrichments less than or equal to 4.54 weight percent and meeting the requirements set forth in Table 4-4.

d) Region lE - Region 1 North Tilt Pit with 4-of-4 loading having nominal planar average U-235 enrichments less than or equal to 4.54 weight percent and meeting the requirements set forth in Table 4-7.

e) Regions 1A, lB & IC can be distributed in Region 1 in any manner providing that any 2-by-2 grouping of cells and the assemblies in them meet the requirements above for the number of cells occupied. For example, for a 4 x 4 group of cells, all of the following configurations must be examined against the above requirements:

M

2) Non-fuel bearing components a) Any component with non-fissile material can be stored in any designated fuel location in Region 1A, IB, 1C, or lE without restriction.

b) If a non-fissile material meets the criteria for a non-fuel bearing component (NFBC) as listed below it can be stored face adjacent to fuel in a designated empty cell in Region IA or lB.

i) The gauge dummy assembly and the lead dummy assembly can be stored:

(1) Diagonally adjacent to each other anywhere in Region 1A, or (2) Anywhere in Regions lB or 1C.

Page 36

A AR EVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit ii) A fuel assembly composed of up to 216 solid SS rods can be stored face adjacent to fuel in a designated empty cell as long as the non-fuel bearing component is at least ten locations away from another NFBC that is face adjacent to fuel.

iii) A component composed of primarily SS that displaces less than 30 in2 of water in any plane within the active fuel can be stored face adjacent to fuel in a designated empty cell as long as the NFBC is at least ten locations away from another non-fuel bearing component that is face adjacent to fuel.

3) Legacy Fuel Storage a) For fuel in batches A through K stored in Region 1, a 1.0 GWD/MTU penalty must be subtracted from the burnup value, as indicated by the core monitoring system, prior to applying the requirements set forth in Licensing Requirement 1) above.

Page 37

AR EVA Document No.: ANP-2858-0O01 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit

7.0 REFERENCES

1. "Quality Assurance Data Final Report, Boron Carbide Neutron Absorbing Plate, NUS Corporation Purchase Order No. PT-5097-9 SI," Research & Development Division, The Carborundum Company, Niagara Falls, New York, September, 1977.

2. NRC Letter to Palisades Nuclear Plant, Docket No. 50-255/License No. DPR-20, "Palisades Plant -

Issuance of Amendment Re: Spent Fuel Pool Region I Storage Requirements (TAC ME0161),"

ML090160238, 2009-02-06.

3. NRC Letter to Palisades Nuclear Plant, Docket No. 50-255/License No. DPR-20, "Palisades Plant -

Issuance of Amendment To Change Enrichment Limits in Fuel Pool (TAC MB 1362)," ML020440048 2002-02-26.

4. SCALE4.4a, "A Modular Code System for Performing Standardized Computer Analysis for Licensing Evaluation," NUREG/CR-0200, Revision 6, May 2000, Oak Ridge National Laboratory (ORNL).

5. M. Edenius, et al., "CASMO A Fuel Assembly Burnup Program," STUDSVIKiNFA-89/3, Studsvik AP, Nyk6ping, Sweden, November 1989.

6 EA-SFP-99-03, "Palisades New Fuel Storage, Fuel Pool and Fuel Handling Criticality Safety Analysis,"

10/23/2000.

7. L. Kopp, ",Guidance on the Regulatory Requirements for Criticality Analysis of Fuel Storage at Light-Water Reactor Power Plants," NRC Memorandum from L. Kopp to T. Collins, August 19, 1998, ML072710248.

8. Nuclear Regulatory Commission, "Guide for Validation of Nuclear Criticality Safety Calculational Methodology," NUREG/CR-6698, January 2001.

9. Palisades Nuclear Plant, Docket No. 50-255, License No. DPR-20, "License Amendment Request for Spent Fuel Pool Region I Criticality, Enclosure 4" ML083360624, November 25, 2008.

10. Shearon Harris Nuclear Power Plant, Unit No. 1 Docket No. 50-400/License No. NPF-63 Request for License Amendment, Framatome ANP, Inc 77-5069740-NP-00, "Shearon Harris Criticality Evaluation."

ML052510504, 2005-08-31.

11. Nuclear Regulatory Commision, "Recommendations for Addresing Axial Bumup in PWR Burnup Credit Analysis," NUREG/CR-680 1, March 2003.

12. Bierman, S.R., Durst, B.M., Clayton, E.D., "Critical Separation Between Subcritical Clusters of 4.29 Wt% 235U Enriched U02 Rods in Water With Fixed Neutron Poisons," Battelle Pacific Northwest Laboratories, NUREG/CR-0073 (PNL-2615).

Page 38

A AR EVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit

13. Baldwin, M. N., et al., "Critical Experiments Supporting Close Proximity Water Storage of Power Reactor Fuel," BAW-1484-7, July 1979.

14. Hoovler, G. S., et al., "Critical Experiments Supporting Underwater Storage of Tightly Packed Configurations of Spent Fuel Pins," BAW-1645-4, November, 1981.

15. "Dissolution and Storage Experimental Program with U[4.75]02 Rods," Transactions of the American Nuclear Society, Vol. 33, pg. 362.

16. Nuclear Energy Agency, "International Handbook of Evaluated Criticality Safety Benchmark Experiments." NEA/NSC/DOC(95)03, Nuclear Energy Agency, Organization for Co-operation and Development, 2002.

17. D'Agostino, R.B. and Stephens, M.A., Goodness-of-fit Techniques. Statistics, Textbooks and Monographs, Volume 68. New York, New York, 1986.

18. ANSI/ANS-57.2 - "Design Requirements for Light Water Reactor Spent Fuel Storage Facilities at Nuclear Power Plants," American Nuclear Society, 1983.

19. Rosenkrantz W.A., Introduction to Probability and Statistics for Scientists and Engineers, The McGraw-Hill, New York, NY, 1989.

20. Owen, D.B., Handbook of Statistical Tables, Addison-Wesley, Reading, MA.

21. EMF-96-029(P)(A), "Reactor Analysis System for PWRs," January 1997.

22. BAW-10180A, "NEMO-NODAL Expansion Method Optimized - Revision 1," March 1993.

23. Natrella, M.G., Experimental Statistics. National Bureau of Standards Handbook 91, Washington, D.C.,

U.S. Deparatment of Commerce, National Bureau of Standards, 1963.

Page 39

A AR EVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit APPENDIX A: KENO-V.A BIAS AND BIAS UNCERTAINTY The purpose of the present analysis is to determine the bias of the krff calculated with SCALE 4.4a computer code by using a statistical methodology to evaluate criticality benchmark experiments that are appropriate for the range of parameters expected for spent fuel pool criticality analysis. The scope of this report is limited to the validation of the KENO-V.a module and CSAS25 driver in the SCALE 4.4a code package for use with the 44 energy group cross-section library 44GROUPNDF5. These results were previously submitted in Reference [10].

This calculation is performed according to the general methodology described in Reference [8] (NUREG/CR-6698 "Guide for Validation of Nuclear Criticality Safety Methodology") that is also briefly described in Section A. 1. The critical experiments selected to benchmark the computer code system are discussed in Section A.4. The results of the criticality calculations, the trending analysis, the basis for the statistical technique chosen, the bias, and the bias uncertainty are presented in Section A.4. Final results are summarized in Section A.8.

A.1 Statistical Method for Determining the Code Bias As presented in Reference [8], the validation of the criticality code must use a statistical analysis to determine the bias and bias uncertainty in the calculation of krff. The approach involves determining a weighted mean of klff that incorporates the uncertainty from both the measurement (aTeyp) and the calculation method (Gcaic). A combined uncertainty can be determined using the Equation 3 from Reference [8], for each critical experiment:

2 3t= (O 'calc + C 'exp2)1/2 The weighted mean oflkff(keff ), the variance about mean (s), and the average total uncertainty of the benchmark experiments (U:2) can be calculated using the weighting factor 1 / o-2 (see Eq. 4, 5, and 6 in Reference [8]). The final objective is to determine the square root of the pooled variance, defined as (Eq. 7 from Reference [8]):

S $2 "-*2 sP= 5S +0U2 The above value is used as the mean bias uncertainty, where bias is determined by the relation:

Bias = keff - 1, if keff is less than 1, otherwise Bias = 0 (Eq. 8 from Reference [8])

The approach for determining the final statistical uncertainty in the calculational bias relies on the selection of an appropriate statistical treatment. Basically, the same steps and methods suggested in

Reference:

[8] for determining the upper safety limit (USL) can be applied also for determining the final bias uncertainty.

First, the possible trends in bias need to be investigated. Trends are identified through the use of regression fits to the calculated kcff results. In many instances, a linear fit is sufficient to determine a trend in bias. Typical parameters used in these trending analyses are enrichment, hydrogen to fuel atom ratio (H/X) or a generic spectral parameter as the energy of the average lethargy causing fission (EALF).

Reference [8] indicates that the use of both weighted or unweighted least squares techniques is an appropriate means for determining the fit of a function. For the present analysis linear regression was used on both weighted Page 40

A AREVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit and unweighted kcff values to determine the existence of a trend in bias. Typical numerical goodness of fit tests was applied afterwards to confirm the validity of the trend.

When a relationship between a calculated keff and an independent variable can be determined, a one-sided lower tolerance band may be used (Reference [8]) to express the bias and its uncertainty. When no trend is identified, the pool of kaff data is tested for normality. If the data is normally distributed, then a technique such as a one-sided tolerance limit is used to determine bias and its uncertainty. Ifthedata is not normally distributed, then a non-parametric analysis method must be used to determine the bias and its uncertainty (Reference [8]).

A.2 Area of Applicability Required for the Benchmark Experiments The spent fuel pool at Palisades will primarily contain commercial nuclear fuel in uranium oxide pins in a square array. This fuel is b6unded by the typical parameter values provided in Table A- 1. These typical values were used as primary tools in selecting the benchmark experiments appropriate for determining the code bias.

Table A-1: Range of Values of Key Parameters in Spent Fuel Pool Parameter Range of Values Fissile material Physical/Chemical Formr Enrichment natural to 5.05 wt% U-235 Moderation/Moderator Heterogeneous/Water Lattice Square Pitch 1.2 to 1.45 cm Clad Zircaloy Soluble Boron Anticipated Absorber/Materials Stainless steel, Boron H/X ratio 0 to 445 Reflection Water, Stainless Steel Neutron Energy Spectrum (Energy of the 0.25 to 2.5 eV Average Lethargy Causing Fission)

Benchmark calculations have been made on selected critical experiments, chosen, in so far as possible, to bound the range of variables in the spent fuel rack designs. In rack designs, the most significant parameters affecting criticality are (1) the fuel enrichment, (2) the '°B loading in the neutron absorber, and (3) the lattice spacing.

Other parameters have a smaller effect but have been also included in the analyses.

Page 41

A AREVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit One possible way of representing the data is through a spectral parameter that incorporates influences from the variations in the parameter. Such a parameter is computed by KENO-V.a, which prints the EALF. The expected range for this parameter was also included in Table A-I above. Note that there are no critical experiments for low density (mist) moderator cases; however, interspersed moderator cases analyzed in subsequent sections demonstrate that the interspersed moderator cases were not limiting (had very low values of kcff) compared to fully flooded (100% dense moderator) cases.

A.3 Description of the Criticality Experiments Selected The set of criticality benchmark experiments has been constructed to accommodate large variations in the range of parameters of the rack configurations and also to provide adequate statistics for the evaluation of the code bias.

One hundred critical configurations were selected from various sources as the International Handbook of Evaluated Criticality Safety Benchmark Experiments (Reference [16]) and previous validation analyses done with configurations from References [12], [13], [14], and [15]. These benchmarks include configurations performed with lattices of U0 2 fuel rods in water having various enrichments and moderating ratios (H/X). A set of MOX criticality benchmarks is also included in the present set (Reference [16]). The area of applicability (AOA) is established within this range of benchmark experiment parameter values.

A brief description of the selected benchmark experiments, including the name of the SCALE 4.4a input files that have been constructed to model them, is presented in Table A-2. The table includes the references where a detailed description of the experiments and their range of applicability are presented.

Table A-2: Descriptions of the Critical Benchmark Experiments Experiment Measured Ia exp I Brief Description Neutron Absorber Reflector Case Name keff

-NUREG/CR-.073 PNL-ex' eriments (Referencefl2])i 21__-.

c00 4 1.0000 0.0020 U0 2 pellets with 4.31 wt% 235U None Water and acrylic c005b 1.0000 0.0018 0.625 cm Al plates plates as well as a c006b 1.0000 0.0019 Cluster of fuel rods on a 25.4 mm 0.625 cm Al plates biological shield c007a 1.0000 0.0021 pitch. Moderator; water or 0.302 cm SS-304L serve as primary cOO8b 1.0000 0.002 1 borated water. plates reflector material.

c009b 1.0000 0.0021 0.298 cm SS-304L A minor cOlOb 1.0000 0.0021 Various separation distances used absorber plates with contribution comes cOl lb 1.0000 0.0021 between clusters. Those so 1.05 wt% or 1.62 from the channel cOl2b 1.0000 0.0021 indicated have plates of neutron wt% B that supports the cOl3b 1.0000 0.0021 absorbing material poison placed 0.485 cm SS-304L rod clusters and cOl4b 1.0000 0.0021 between clusters of fuel rods. For plates the 9.52 mm 1.000additional details on the c029 00021Zircaloy-4 absorber carbon steel tank c029b 1.0000 0.0021 experiments and the computer plates wall.

c03Ob 1.0000 0.0021 models used, see Reference [ 18] plates c03 lb 1.0000 0.0021 and evaluated experiments LEU- Boral absorber COMP-THERM 002 and LEU- plates COMP-THERM-009 in Reference

[4].

Page 42

A AREVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit Experiment Measured [ exp Brief Description Neutron Absorber Reflector Case Name kcff

ýBAW-PI,84- x" 1im:iis(Rfrne 1) aclpl 1.0002 0.0005 Enrichments of 2.459 wt% 235U None Water and aclp2 1.0001 0.0005 3x3 array of fuel clusters. 1037 ppm boron aluminum base aclp3 1.0000 0.0006 Various B 4C pins and stainless 764 ppm boron plate are the aclp4 0.9999 0.0006 steel and boron-aluminum sheets None primary reflective aclp5 1.0000 0.0007 were used as neutron absorbers. None materials in the aclp6 1.0097 0.0012 Cases so indicated also had None experiments.

aclp7 0.9998 0.0009 dissolved boron in the water None Minor contribution aclp8 1.0083 0.0012 moderator. None from the steel tank aclp9 1.0030 0.0009 None walls aclpl0 1.0001 0.0009 143 ppmboron aclpl la 1.0000 0.0006 510 ppm boron aclpl lb 1.0007 0.0007 514 ppm boron aclp l c 1.0007 0.0006 501 ppm boron aclp I Id 1.0007 0.0006 493 ppm boron aclpIl e 1.0007 0.0006 474 ppm boron aclp IIf 1.0007 0.0006 462 ppm boron aclpl lg 1.0007 0.0006 432 ppm boron aclpl2 1.0000 0.0007 217 ppm boron aclpl3 1.0000 0.0010 15 ppm boron aclpl3a 1.0000 0.0010 28 ppm boron aclpl4 1.0001 0.0010 92 ppm boron aclpl5 0.9998 0.0016 395 ppm boron aclpl6 1.0001 0.0019 121 ppm boron aclpl7 1;0000 0.0010 487 ppm boron aclpl8 1.0002 0.0011 197 ppm boron aclpl9 1.0002 0.0010 634 ppm boron aclp20 1.0003 0.0011 320 ppm boron aclp2l 0.9997 0.0015 72 ppm boron BAW-1 ~~6i5ep'erifinents. eeenel 235 rconO1 1.0007 0.0006 2.46 wt% U 435 ppm boron Water and rcon02 1.0007 0.0006 426 ppm boron aluminum base rcon03 1.0007 0.0006 5x5 array of fuel cluster. Rod 406 ppm boron plate are the rcon04 1.0007 0.0006 pitch between 1.2093 cm and 383 ppm boron primary reflective rcon05 1.0007 0.0006 1.4097 cm. Cases so indicated 354 ppm boron materials in the rcon06 1.0007 0.0006 also had dissolved boron in the 335 ppm boron. experiments.'

rcon07 1.0007 0.0006 water moderator. 361 ppm boron Minor contribution rcon08 1.0007 0.0006 121 ppm boron from the steel tank rcon09 1.0007 0.0006 886 ppm boron walls.

rconlO 1.0007 0.0006 871 ppm boron rcon 11 1.0007 0.0006 852 ppm boron rconl2 1.0007 0.0006 834 ppm boron rconl3 1.0007 0.0006 815 ppm boron rconl4 1.0007 0.0006 781 ppm boron rconl5 1.0007 0.0006 746 ppm boron rconl6 1.0007 0.0006 1156 ppm boron rconl7 1.0007 0.0006 1141 ppm boron rconl8 1.0007 0.0006 1123 ppm boron Page 43

A Document No.: ANP-2858-001 AREVA AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit Experiment Measured a exp Case Name k~ff rconl9 1 1.0007 1 0.0006 rcon20 1.0007 0.0006 rcon2l 1.0007 0.0006 CEA Valduic CriticalMass Ldboratb mdis0l 1.0000 0.0014 mdis02 1.0000 0.0014 reflector mdis03 1.0000 0.0014 CEA Valduc Critical Mass boundaries vary mdis04 1.0000 0.0014 Laboratory experiments. A key from case to mdis05 1.0000 0.0014 aspect of these experiments was case.

mdis06 1.0000 0.0014 to examine the reactivity effects mdis07 1.0000 0.0014 of differing densities of mdis08 1.0000 0.0014 hydrogenous materials within a cross shaped channel box placed mdis09 1.0000 0.0014 between a two by two array of mdisl0 1.0000 0.0014 fuel rod assemblies. The mdisl _1 1.0000 0.0014 assemblies each consisted of an mdisl2 1.0000 0.0014 18 x 18 array of aluminum alloy mdisl3 1.0000 0.0014 clad fuel U02 pellet columns.

mdisl4 1.0000 0.0014 mdisl5 1.0000 0.0014 The reader is referred to mdisl6 1.0000 0.0014 Reference [18] for a description mdisl7 1.0000 0.0014 of the critical mass experiments mdisl8 1.0000 0.0014 and the computer models used mdis19 1.0000 0.0014 for these validation cases.

LEU-COMP-THERM-022,-"-024,-025:Experiments: (Refeience116]).-- ___ _, _

leuct022-02 1.0000 0.0046 9.83 and 7.41 wt% enriched None Water is the leuct022-03 1.0000 0.0036 U02 rods of varying numbers in primary reflector.

leuct024-01 1.0000 0.0054 hexagonal and square lattices in leuct024-02 1.0000 0.0040 water. Minor leuct025-01 1.0000 0.0041 contribution from leuct025-02 1.0000 0.0044 the steel tank walls.

Mixed Oxide (Refereice" 11i6)', ,

epri70b 1.0009 0.0047 Experiments with mixtures of 687.9 ppm boron Reflected by water (PNL-31) natural U02-2wt%PuO2 and Al.

epri70un 1.0024 0.0060 (8%240Pu). 1.7 ppm boron (PNL-30) epri87b 1.0024 0.0024 Square pitched lattices, with 1090.4 ppm boron (PNL-33) 1.778 cm, 2.2098 cm, and epri87un 1.0042 0.0031 2.5146 cm pitch in borated or 0.9 ppm boron (PNL-32) pure water moderator.

Epri99b 1.0029 0.0027 767.2 ppm boron (PNL-35)

Epri99un 1.0038 0.0025 1.6 ppm boron (PNL-34)

Page 44

A AREVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit Experiment Measured a exp Brief Description Neutron Absorber Reflector Case Name kcff saxtn104 1.0000 0.0023 Experiments with mixtures of None Reflected by water (case 6) natural U02-6.6wt%PuO2 and Al.

saxtn56b 1.0000 0.0054 mixed-oxide (MOX), square- 337 ppm boron (case 3) pitched, partial moderator height saxtn792 1.0049 0.0027 lattices. None (case 5) saxton52 1.0028 0.0072 Moderator: borated or pure None (case 1) water moderator.

saxton56 1.0019 0.0059 None (case 2)

(PNL-35)

A.4 Results of Calculations with SCALE 4.4a The critical experiments described in Section A.3 were modeled with the SCALE 4.4a computer system. The resulting keff and calculational uncertainty, along with the experimental keff and experimental uncertainty are tabulated in Table A-3. The parameters of interest in performing a trending analysis of the bias (including EALF calculated by SCALE 4.4a) are also included in the table.

Table A-3: Results for the Selected Benchmark Experiments No Case name Benchmark values SCALE 4.4a EALF Enrichment B H/X Calculated Values (eV) wt% 235U (ppm) keff U-ep k~f U-ca 1 c004 1.0000 0.002 0.9966 0.0008 0.1126 4.31 0.0 255.92 2 c005b 1.0000 0.0018 0.9950 0.0008 0.1128 4.31 0.0 255.92 3 c006b 1.0000 0.0019 0.9964 0.0008 0.1130 4.31 0.0 255.92 4 c007a 1.0000 0.0021 0.9973 0.0009 0.1128 4.31 0.0 255.92 5 cOO8b 1.0000 0.0021 0.9966 0.0008 0.1135 4.31 0.0 255.92 6 c009b 1.0000 0.0021 0.9967 0.0008 0.1136 4.31 0.0 255.92 7 c0lOb 1.0000 0.0021 0.9977 0.0008 0.1142 4.31 0.0 255.92 8 cOl lb 1.0000 0.0021 0.9949 0.0009 0.1143 4.31 0.0 255.92 9 cO2b 1.0000 0.0021 0.9967 0.0008 0.1148 4.31 0.0 255.92 10 cO13b 1.0000 0.0021 0.9969 0.0008 0.1130 4.31 0.0 255.92 11 cO4b 1.0000 0.0021 0.9958 0.0008 0.1133 4.31 0.0 255.92 12 c029b 1.0000 0.0021 0.9972 0.0008 0.1126 4.31 0.0 255.92 13 c03Ob 1.0000 0.0021 0.9972 0.0009 0.1132 4.31 0.0 255.92 14 c03 lb 1.0000 0.0021 0.9993 0.0009 0.1144 4.31 0.0 255.92 15 ACLPI 1.0002 0.0005 0.9912 0.0007 0.1725 2.46 0.0 215.57 16 ACLP2 1.0001 0.0005 0.9951 0.0006 0.2504 2.46 1037.0 215.79 17 ACLP3 1.0000 0.0006 0.9958 0.0006 0.1963 2.46 764.0 215.83 18 ACLP4 0.9999 0.0006 0.9889 0.0008 0.1912 2.46 0.0 215.91 19 ACLP5 1.0000 0.0007 0.9906 0.0007 0.1660 2.46 0.0 215.87 20 ACLP6 1.0097 0.0012 0.9899 0.0009 0.1712 2.46 0.0 215.87 21 ACLP7 0.9998 0.0009 0.9891 0.0008 0.1496 2.46 0.0 215.87 22 ACLP8 1.0083 0.0012 0.9873 0.0007 0.1537 2.46 0.0 215.87 23 ACLP9 1.0030 0.0009 0.9908 0.0008 0.1409 2.46 0.0 215.87 24 ACLP10 1.0001 0.0009 0.9916 0.0007 0.1495 2.46 143.0 215.22 25 ACP11A 1.0000 0.0006 0.9948 0.0007 0.1996 2.46 510.0 215.32 26 ACPllB 1.0007 0.0007 0.9947 0.0007 0.1994 2.46 514.0 215.73 27 ACP11C 1.0007 0.0006 0.9944 0.0006 0.2019 2.46 501.0 215.32 28 ACPIHD 1.0007 0.0006 0.9952 0.0007 0.2028 2.46 493.0 215.14 29 ACPlIE 1.0007 0.0006 0.9940 0.0006 0.2037 2.46 4.74.0 214.70 30 ACPI IF 1.0007 0.0006 0.9932 0.0007 0.2050 2.46 462.0 214.52 Page 45

A ARE VA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit No Case name Benchmark values SCALE 4.4a EALF Enrichment B H/X 235 Calculated Values (ev) wt% U (ppm) keff acxp kcff Ocnk 31 ACPIlG 1.0007 0.0006 0.9954 0.0007 0.2045 2.46 432.0 215.97 32 ACLP12 1.0000 0.0007 0.9930 0.0008 0.1700 2.46 217.0 215.05 33 ACLP13 1.0000 0.001 0.9933 0.0008 0.1965 2.46 15.0 215.67 34 ACPI3A 1.0000 0.001 0.9902 0.0007 0.1981 2.46 28.0 215.91 35 ACLPI4 1.0001 0.001 0.9891 0.0008 0.2011 2.46 92.0 215.83 36 ACLP15 0.9998 0.0016 0.9855 0.0007 0.2063 2.46 395.0 215.83 37 ACLP16 1.0001 0.0019 0.9856 0.0007 0.1730 2.46 121.0 215.83 38 ACLPI7 1.0000 0.001 0.9899 0.0006 0.2053 2.46 487.0 215.89 39 ACLPI8 1.0002 0.0011 0.9886 0.0008 0.1725 2.46 197.0 215.89 40 ACLP19 1.0002 0.001 0.9912 0.0006 0.2061 2.46 634.0 215.89 41 ACLP20 1.0003 0.0011 0.9899 0.0007 0.1730 2.46 320.0 215.89 42 ACLP21 0.9997 0.0015 0.9883 0.0008 0.1532 2.46 72.0 216.19 43 RCON01 1.0007 0.0006 0.9997 0.0007 2.4282 2.46 435.0 17.41 44 RCON02 1.0007 0.0006 1.0004 0.0007 2.4360 2.46 426.0 17.40 45 RCON03 1.0007 0.0006 0.9985 0.0008 2.4972 2.46 406.0 17.40 46 RCON04 1.0007 0.0006 0.9983 0.0007 2.4989 2.46 383.0 17.41 47 RCON05 1.0007 0.0006 1.0002 0.0007 2.4988 2.46 354.0 17.41 48 RCON06 1.0007 0.0006 0.9982 0.0007 2.5119 2.46 335.0 17.41 49 RCON07 1.0007 0.0006 0.9984 0.0006 1.6313 2.46 361.0 17.43 50 RCON08 1.0007 0.0006 1.0155 0.0008 1.1134 2.46 121.0 17.43 51 RCON09 1.0007 0.0006 0.9973 0.0007 1.4481 2.46 886.0 44.81 52 RCONI0 1.0007 0.0006 0.9982 0.0008 1.4623 2.46 871.0 44.81 53 RCON11 1.0007 0.0006 0.9958 0.0007 1.5006 2.46 852.0 44.79 54 RCON12 1.0007 0.0006 0.9979 0.0007 1.4942 2.46 834.0 44.81 55 RCON 13 1.0007 0.0006 0.9971 0.0006 1.4973 2.46 815.0 44.81 56 RCONI4 1.0007 0.0006 0.9967 0.0007 1.5185 2.46 781.0 44.79 57 RCON15 1.0007 0.0006 0.9980 0.0006 1.5122 2.46 746.0 44.79 58 RCONI6 1.0007 0.0006 0.9954 0.0006 0.4182 2.46 1156.0 118.47 59 RCONI7 1.0007 0.0006 0.9963 0.0007 0.4293 2.46 1141.0 118.47 60 RCON18 1.0007 0.0006 0.9929 0.0007 0.4354 2.46 1123.0 118.44 61 RCON19 1.0007 0.0006 0.9952 0.0007 0.4371 2.46 1107.0 118.44 62 RCON20 1.0007 0.0006 0.9952 0.0007 0.4367 2.46 1093.0 118.44 63 RCON21 1.0007 0.0006 0.9945 0.0007 0.4404 2.46 1068.0 118.44 64 RCON28 1.0007 0.0006 0.9970 0.0008 0.9984 2.46 121.0 17.44 65 MDIS01 1.0000 0.0014 0.9929 0.0008 0.2822 4.74 0.0 137.61 66 MDIS02 1.0000 0.0014 0.9862 0.0009 0.2641 4.74 0.0 137.61 67 MDIS03 1.0000 0.0014 0.9845 0.0009 0.2636 4.74 0.0 137.61 68 MDIS04 1.0000 0.0014 0.9895 0.0008 0.2513 4.74 0.0 137.61 69 MDIS05 1.0000 0.0014 0.9901 0.0009 0.2411 4.74 0.0 137.61 70 MDIS06 1.0000 0.0014 1.0010 0.0008 0.2292 4.74 0.0 137.61 71 MDIS07 1.0000 0.0014 0.9901 0.0009 0.2250 4.74 0.0 137.61 72 MDIS08 1.0000 0.0014 0.9858 0.0008 0.2493 4.74 0.0 137.61 73 MDIS09 1.0000 0.0014 0.9856 0.0009 0.2483 4.74 0.0 137.61 74 MDIS1O 1.0000 0.0014 0.9928 0.0009 0.2221 4.74 0.0 137.61 75 MDISll 1.0000 0.0014 1.0029 0.0009 0.2043 4.74 0.0 137.61 76 MDIS12 1.0000 0.0014 1.0080 0.0008 0.1946 4.74 0.0 137.61 77 MDISI3 1.0000 0.0014 0.9916 0.0009 0.1947 4.74 0.0 137.61 78 MD1SI4 1.0000 0.0014 0.9887 0.0008 0.2299 4.74 0.0 137.61 79 MDISI5 1.0000 0.0014 0.9881 0.0010 0.2270 4.74 0.0 137.61 80 MDISI6 1.0000 0.0014 1.0015 0.0008 0.1905 4.74 0.0 137.61 81 MDIS17 1.0000 0.0014 0.9987 0.0008 0.1794 4.74 0.0 137.61 82 MDIS18 1.0000 0.0014 0.9961 0.0008 0.1747 4.74 0.0 137.61 83 MDISI9 1.0000 0.0014 0.9928 0.0009 0.1747 4.74 0.0 137.61 84 leuct022-02 1.0000 0.0046 1.0056 0.0013 0.2920 9.83 0.0 80.00 85 leuct022-03 1.0000 0.0036 1.0048 0.0013 0.1253 9.83 0.0 151.00 86 leuct024-01 1.0000 0.0054 0.999 0.0015 1.0568 9.83 0.0 41.00 87 leuct024-02 1.0000 0.0040 1.0048 0.0014 0.1435 9.83 0.0 128.00 88 leuct025-01 1.0000 0.0041 0.9851 0.0014 0.4401 7.41 0.0 66.30 89 leuct025-02 1.0000 0.0044 0.9936 0.0013 0.2015 7.41 0.0 106.10 90 epri70b (PNL-31) 1.0009 0.0047 0.9995 0.0016 0.7631 - 688.0 146.15 91 epri70un (PNL-30) 1.0024 0.0060 0.9967 0.0015 0.5648 2.0 146.20 92 epri87b (PNL-33) 1.0024 0.0024 1.0046 0.0013 0.2780 1090.0 308.83 93 epri87un (PNL-32) 1.0042 0.0031 1.0034 0.0013 0.1894 1.0 308.99 Page 46

A AR IEVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit No Case name Benchmark values SCALE 4.4a EALF Enrichment B H/X 235 Calculated Values (eV) wt% U (ppm) klff Gcxp kcff Gý.[ý 94 epri99b (PNL-35) 1.0029 0.0027 1.0066 0.0009 0.1802 767.0 445.41 95 epri99un (PNL-34) 1.0038 0.0025 1.0088 0.0019 0.1353 2.0 445.57 96 saxtn104 (case 6) 1.0000 0.0023 1.0056 0.0017 0.1001 0.0 473.11 97 saxtn56b (case 3) 1.0000 0.0054 0.998 0.0019 0.6523 3:37.0 95.24 98 saxtn792 (case 5) 1.0049 0.0027 1.0027 0.0019 0.1547 0.0 249.70 99 saxton52 (case 1) 1.0028 0.0072 0.9987 0.0013 0.8878 0.0 73.86 100 saxton56 (case 2) 1.0019 0.0059 0.9997 0.0018 0.5450 0.0 95.29 In order to address situations in which the critical experiment being modeled was at other than a critical state (i.e.,

slightly super or subcritical), the calculated koff is normalized to the experimental lxp, using the following formula (Eq.9 from Reference [8]):

knorn

. kcalc /Ik,5 p In the following, the normalized values of the keff were used in the determination of the code bias and bias uncertainty.

A.5 Trending Analysis The next step of the statistical methodology used to evaluate the code bias for the pool of experiments selected is to identify any trend in the bias. This is done by using the trending parameters presented in Table A-4.

Table A-4: Trending Parameters Energy of the Average Lethargy causing Fission (EALF) 235 Fuel Enrichment (wt% U)

Atom ratio of the moderator to fuel (H/X)

Soluble Boron Concentration The first step in calculating the bias uncertainty is to apply regression-based methods to identify any trending of the calculated values of keff with the spectral and/or physical parameters. The trends show the results of systematic errors or bias inherent in the calculational method used to estimate criticality.

For the critical benchmark experiments that were slightly super or subcritical, an adjustment to the kcff value calculated with SCALE 4.4a (klate) was done as suggested in Reference [8]. This adjustment is done by normalizing the calculated (kcalc) value to the experimental value (kexp). This normalization does not affect the inherent bias in the calculation due to very small differences in k~ff. Unless otherwise mentioned, the normalized koff values (knorm) have been used in all subsequent calculations.

Each subset of normalized klff values is first tested for trending against the spectral and/or physical parameters of interest (in this case, presented in Table A-4 above), using the built-in regression analysis tool from any general statistical software (e.g., Excel). Trending in this context is linear regression of unweighted calculated kcff on the predictor variable(s) (spectral and/or physical parameters). In addition, the equations presented in Reference [8]

are also applied to check a linear dependency in case of weighted keff, using as weight the factor 1/ o-2 as previously discussed.

Page 47

AR EVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit The linear regression fitted equation is in the form y(x) = a + bx, where y is the dependent variable (krff) and x is any of the predictor variables mentioned in Table A-4. The difference between the predicted y and actual value of it is known as the random error component (residuals).

The final validity of each linear trend is checked using well-established indicators or goodness-of-fit tests concerning the regression parameters. As a first indicator, the coefficient of determination (r2) that is available as a result of using linear regression statistic can be used to evaluate the linear trending. It represents the proportion of the sum of squares of deviations of the y values about their mean that can be attributed to a linear relation between y and x.

Another assessment of the adequacy of the linear model can be done by checking the goodness-of-fit against a null hypothesis on the slope (b) (Reference [19], p. 371). The slope test requires calculating the test statistic "T' as in the following equation along with the corresponding statistical parameters (Reference [19], p. 371).

T=A iS~

where, A81is the estimated slope of the fitted linear regression equation i=1,n

and, (n - 2) ,= , t )

where, 5i is the estimated value using the regression equation.

The test statistic is compared to the Student's t-distribution (t,/2,n-2 ) with 95% confidence and n-2 degrees of freedom (Reference [23]p.T-5), where n is the initial number of points in the subset. Given a null hypothesis H0:P31=0, of "no statistically significant trend exists (slope is zero)", the hypothesis would be rejected if TJ >

ta/2,n-2. By only accepting linear trends that the data supports with 95% confidence, trends due to the randomness of the data are eliminated. A good indicator of this statistical process is evaluation of the P-value probability (calculated by the regression tool in Excel) that gives a direct estimation of the probability of having a linear trending due only to chance.

The last step employed as part of the regression analysis is determining whether or not the final requirements of the simple linear regression model are satisfied. The error components (residuals) need to be normally distributed with mean zero, and also the residuals need to show a random scatter about the center line (no pattern). These requirements were verified for the present calculation using the built-in statistical functions in Excel and by applying an omnibus normality test (Anderson-Darling, Reference [ 17] p.372]) on the residuals.

The results of the trending parameter analysis for the criticality benchmark set (unweighted kff) are summarized in Table A-5.

Page 48

A AREVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit Table A-5: Summary of Trending Analysis Trend Valid Parameter n Intercept Slope r2 T tO.025,n-2 P-value Goodness-of-fit Tests Trend EALF 100 0.9937 0.002 0.061 2.53 1.987 0.013 Not Passed (residuals No not normal and show a pattern -see Figure A-5)

Enrichment 90a 0.9911 0.0008 0.070 2.57 1.991 0.012 Not passed (residuals No 23 (wt% 1U) not normal and show a pattern - see Figure A-6)

H/X 100 0.9952 -2.2E-06 0.001 - 1.987 0.714 Not Passed No 0.37 Boron in 100 0.9945 1.5E-06 0.009 0.95 1.987 0.345 Not passed No moderator (ppm) 1NoLe: BenchmarIk epeimnt WItH1 IVI'.JA. uel excluded.

The results in above table show that there are no statistically significant and valid trends of kff with the trending parameters. An additional check was done by determining if there are any trends on the weighted data. The results of the regression analysis obtained using weighted kff (with the weight factor 1/a ' as previously discussed) show that the determination coefficient (r 2) has similar low values as in the above table, evidencing very weak and statistically insignificant trends.

Figure A-I to Figure A-6 show the distribution of the normalized krff values versus the trending parameters investigated.

Figure A-I: Distribution of keff Data versus EALF for the Selected Pool of Benchmark Experiments Page 49

A AREVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit Figure A-2: Distribution of keff Data versus Enrichment (235U) for the Selected Pool of Benchmark Experiments 1.02 1.01 1-0.99 Ii:

I 0.98 S 0.97 1 0.0 0 1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00 Enrichment (wt%)

Figure A-3: Distribution of keff Data versus H/X for the Selected Pool of Benchmark Experiments 1.02 1.01 1

!9

-19 0.99 0.98 0.97 , ,

0.00 50.00 100.00 150.00 200.00 250.00 300.00 350.00 400.00 450.00 500.00 H/X Page 50

A AR EVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit Figure A-4: Distribution of keff Data versus Soluble Boron Concentration for the Selected Pool of Benchmark Experiments 1.02 1.01 1

0.99 0.98 0.97 1 ,

0.00 200.00 400.00 600.00 800.00 1000.00 1200.00 1400.00 Boron (ppm)

Figure A-5: Plot of Standard Residuals for Regression Analysis with EALF as Trending.

Parameter 4.0000 3.0000 2.0000 -- -*

"o 1.0000 M 0.0000 _-____

0.000 0W000 1.0000 1.5-0 0 2.0000 2.5%00 3.0 )00 U) -1.0000 R-

-2.0000

-3.0000 EALF (eV)

Page 51

A AREVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit Figure A-6: Plot of Standard Residuals for Regression Analysis with Enrichment as Trending Parameter 5.0000 4.0000 3.0000 i 2.0000 1.0000 0.0000 0.1

-1.0000

-2.0000

-3.0000 23 5 Enrichment (wt % U)

A.6 Bias and Bias Uncertainty For situations in which no significant trending in bias is identified, the statistical methodology presented in Reference [8] suggests to first check the normality of the pool of krff data. Applying the Shapiro-Wilk test (Reference [8]) the null hypothesis of a normal distribution is not rejected. A visual inspection of the normal probability plot of the keff data is also evidencing that the pool of k~ff data for the selected benchmarks can be considered normally distributed.

This situation allows the application of the weighted single-sided lower tolerance limit to determine the bias uncertainty (Reference [8]). First by determining of the factor for 95% probability at the 95% confidence level (C 95 /9 5 ) and then multiplying it with the evaluated square root of the pooled variance, the uncertainty limit is determined.

From Reference [20], C 9 5 /95 for n equal to 100 is 1.927. The square root of the pooled variance calculated using the formulas presented is:

S, + 5-2 = (2.45212E-05+1.63005E-06) 0.5 =0.00511 Bias Uncertainty = C 9 5 /9 5 "* Sp = 1.927

0.00511 = 0.00985 The bias is obtained using the formula that includes the weighted average of kff Bias = /ff - 1 = 0.99458 - 1 = -0.00542 Page 52

A AR EVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit These represent the final results that can be further used to evaluate the maximum keff values in the criticality analysis of the Palisades spent fuel pool.

A.7 Areas of Applicability A brief description of the spectral and physical parameters characterizing the set of selected benchmark experiments is provided in Table A-6.

Table A-6: Range of Values of Key Parameters in Benchmark Experiments Parameter Range of Values Geometrical shape Heterogeneous lattices; Rectangular and hexagonal Fuel type U0 2 rods MOX fuel rods Enrichment (for U0 2 fuel) 2.46 to 9.83 wt % 235.U Lattice pitch 1.04 to 2.6416 cm H/X 17.4 to 445 EALF 0.11 to 2.51 eV Absorbers Soluble boron Boron in plates Reflectors Water Stainless Steel Aluminum A.8 Bias Summary and Conclusions The results of this evaluation for a selected set of criticality benchmark experiments with enrichments ranging from about 2.5 to about 10 wt% 235U and including also some experiments with MOX fuel rods provide the following information relative to the SCALE4.4a bias.

Bias = kTff - 1 = 0.99458 - 1 = -0.00542 Note that this bias will be applied as a positive penalty in the equation for computation of kmax.

Bias Uncertainty = C 95/95" S = 1.927

0.00511 = 0.00985 The bias and its uncertainty (95/95 weighted single-sided tolerance limit) was obtained applying the appropriate steps of the statistical methodology presented in Reference [8] (NUREG 6698) taking into account the possible trending of koff with various spectral and/or physical parameters. The results are intended to support the criticality analysis of Palisades spent fuel pool.

Page 53

A AR EVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit APPENDIX B: CASMO CALCULATIONS FOR BURNUP This section describes the methods and results for the burnup credit analysis. A summary of key aspects of the burnup credit analysis is given in the following table:

Table B-i: Depletion Modeling Considerations Parameter Value/Model Comment Bumup Uncertainty 5% of the reactivity decrement from 0 Standard value consistent with burnup and the bumup of interest Reference [6]

Measured Bumup Uncertainty 10% Conservatively large value taken.

Sm Equilibrium value More conservative than using peak Sm.

Peak Sm is less for low power operation at end of cycle.

Xe Zero Pu239+Pu241 Buildup

Moderator temperature chosen to maximize Pu production by hardening the spectrum.

All Np-239 is assumed instantly decayed to Pu239.

Axial Burnup Profile 0 10 axial nodes used.

3 axial shapes taken from Reference [11], validated against core monitoring data.

Fuel Temperature 0 1260 OF (955.4K). 100 OF higher Conservatively high to increase than maximum predicted fuel production of Pu through resonance temperature. absorption.

Moderator Temperature 0 A bounding axial temperature Conservatively high to harden spectrum profile was calculated. and increase Pu production.

Soluble Boron Concentration 0 Cycle-average concentration of 700 ppm.

Core Power

Nominal value of 2565.4 MW Operating History

Nominal, unrodded Fixed/Integral Burnable absorbers 0 None modeled Conservative to ignore Gad integral poisons and lumped burnable poisons are currently not used.

Page 54

A AR EVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit B.1 BUC Calculational Method The Palisades Region 1 storage rack used the fixed spacing, burnup credit (BUC), and soluble boron (PPM) credit to provide safe storage of discharged fuel assemblies. The application of BUC requires more calculations than the typical fresh fuel rack analysis. For BUC applications the reactivity effect of the following items must be evaluated and factored into the analysis:

Operating history of the fuel including fuel and moderator temperatures

Axial burnup distributions as a function of assembly average burmup a 5% uncertainty of reactivity decrement due to burnup 0 Measured burnup uncertainty These parameters contribute to the residual reactivity of the burned fuel with the axial distribution having a significant impact at higher assembly average burnups.

The methodology used to apply BUC utilizes CASMO-3 to generate the fuel assembly isotopic composition at a given burnup for each axial assembly node. CASMO-3 is used for the generation of cross sections and depleted isotopes for the PRISM and NEMO core simulators, which are used to support licensing and operation of PWRs.

The adequacy of CASMO-3 for this usage is reflected in the results provided in the PRISM and NEMO Topical reports, References [21] and [22], respectively.

For this analysis, the Batch XI assembly is used. The isotopics are then provided to KENO-V.a to perform the kcff calculations for the specific SFP rack configuration and loading. The process is complicated by the fact that KENO-V.a cross section data bases do not have the ability to accept all of the isotopes for a burned assembly (i.e.,

actinides plus all fission products) and CASMO-3 uses a "lumped" fission product cross section set. Therefore, an intermediate step is needed in which CASMO-3 is used to perform a reactivity equivalencing calculation with the rack geometry for the given burnup state point in which B-10 is used to represent the lumped fission products.

Within KENO-V.a, the generated Sm-149 is explicitly modeled, the Xe-135 concentration is set to 0, the Np-239 is added to Pu-239, and all other fission products are modeled as B-10. The following additional isotopes are transferred from CASMO-3 to KENO-V.a: U-235, U-236, U-238, Pu-240, Pu-241, and 0-16.

Thus, the isotopic composition provided to KENO-V.a represents an equivalent reactivity composition which is supported by the KENO-V.a cross section data base.

B.1.1 Assembly Operation and Depletion Data In order to perform the burnup credit (BUG) SFP storage rack calculations the design basis fuel assembly must be characterized with in-core depletion calculations. The depletion calculations are intended to maximize the assembly reactivity at a given burnup by conservatively modeling moderator and fuel temperatures during reactor operation. This section documents the reactor operational data needed to perform the CASMO-3 depletion calculations.

Page 55

A AREVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit The moderator temperatures and fuel temperatures are sensitive to operating temperatures, which are a function of core power level and RCS core flow. A bounding axial temperature profile was calculated based on an inlet temperature of 544°F and a temperature rise across the assembly of 58.3 OF. These values are shown in Table B-2.

Note that the resulting moderator temperature distribution provides a core exit temperature that is near, or slightly above, the value that is allowed by plant operating Technical Specifications.

Table B-2: Axial Moderator Temperature Distribution Node Center (cm) Temperature (°C) Temperature (K) 9.36 284.5 557.7 28.06 286.5 559.7 46.78 287.8 561.0 84.20 292.7 565.9 140.42 298.7 571.9 196.46 304.7 577.9 252.61 311.0 584.2 290.03 314.6 587.8 308.75 315.9 589.1 327.45 316.8 590.0 A conservative fuel temperature of 1260 °F (955.4K) is used for all nodes. This includes a 100 OF allowance to the maximum estimated fuel temperature of 1160 OF (PRISM core averaged at each axial node). A conservative (higher) moderator and fuel temperature produces more fissile material (i.e., Pu-239).

B.1.2 Assembly Axial Burnup Data for Rack BUC Analysis Typical burnup credit analyses submitted to the US NRC have used a uniform, average burnup distribution over the entire length of the assembly. Such a uniform distribution underestimates the burnup at the center of the assembly and over estimates the burnup at the top and bottom of the assembly. Thus, to adequately utilize bumup credit the impact of the axial bumup distribution at any given assembly average burnup must be understood. This requires that an estimate of the reactivity effects of the axial burnup distribution relative to a uniform distribution be determined and appropriately applied to the results (i.e., an axial bumup distribution penalty factor).

Alternatively, an explicit axial burnup distribution can be modeled in KENO-V.a calculations directly which removes the need for application of an axial bumup distribution penalty. The BUC evaluation for the Palisades SFP racks will use the latter approach (i.e., use an explicit axial burnup distribution).

The relative axial distribution provided in Table B-3 is derived from NUREG/CR-6801, and has been shown to be applicable to Palisades, based on PRISM (Reference [21]) code output and data reports for Palisades Cycles 18-21 (see Figure B-l), which are representative of past and future operations. Note that these axial burnup values are independent of the initial enrichment of the fuel, and generally the burnup in the top of the core is higher for the EOC burnup profiles (lines) than the bounding profile (circles) from NUREG/CR-6801 except for the very top node, which is an axial blanket with reduced enrichment.

Page 56

A AREVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA end Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit Table B-3: 15 and 30 GWD/MTU Burnup Profiles - 336.81 cm Height Center Node Top Node Burnup KENO Node Burnup KENO Node Axial 15 Node 30 GWD/MTU Burnup Height GWD/MTU Burnup cm cm 9.36 18.71 9.74 9.74 18.57 18.57 28.06 37.42 15.66 15.66 27.72 27.72 46.78 56.13 18.12 18.12 31.68 31.68 65.48 74.84 18.23 18.19 32.91 33.01 84.20 93.57 18.21 33.09 102.93 112.28 18.12 33.03 121.62 131.02 17.96 17.87 33.09 33.40 140.42 149.73 17.84 33.36 159.04 168.44 17.82 33.75 177.84 187.15 17.88 17.89 34.08 34.22 196.46 205.82 17.93 34.29 215.19 224.53 17.85 34.29 233.88 243.24 17.34 14.67 34.08 32.98 252.61 261.97 15.33 33.45 271.33 280.68 11.34 31.41 290.03 299.39 9.21 9.21 26.46 26.46 308.75 318.10 7.22 7.22 21.03 21.03 327.45 336.81 4.26 4.26 13.68 13.68 Page 57

A ARE VA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit Figure B-I: Burnup profiles for Cycles 18-21 for burnups 30-34 GWD/MTU (EOC burnup profiles (lines) and the bounding profile (circles). The locations of the upper and lower blankets are indicated by gray lines.)

C) a)

0L_

0 c~o

°L (D

C:;

6 0 50 100 150 200 250 300 height (cm)

B.1.3 Isotopics Generation Method The process of generating isotopic data set for a given assembly burnup begins with a CASMO-3 hot full power in-core depletion with selected core fuel and moderator temperatures. Generally, a CASMIO-3 restart file is written to save the assembly depletion data to facilitate repeated use. A set CASMO-3 restart calculation(s) at the selected burnup state point is then performed to generate isotopic data set which is supported by KENO-V.a and represents a reactivity equivalent assembly in the SFP rack geometry. The general process is outlined as follows:

1) Develop a base CASMO-3 input deck for the Palisades fuel assembly in a standard infinite lattice depletion model of the type used for in-core modeling. Create a second CASMO-3 model of that assembly in a fuel rack cell.

2) Obtain the appropriate axial burnup shape for the desired assembly averaged burnup. Segment this axial shape to fit a 10-node axial model in KENO-V.a, and determine a burnup value for each node. Determine a conservative moderator temperature (i.e., one that is higher than nominal) for each node. Use a conservative fuel temperature (i.e., one that is higher than nominal) for each node.

3) For each burnup value determined in step 2, use the CASMO-3 depletion model to deplete the fuel to that burnup at the determined fuel and moderator temperatures. The top and bottom axial nodes are modeled Page 58

A AR EVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit with the same enrichment as the rest of the assembly rather than a reduced enrichment for the axial blanket regions. Write a restart file.

4) Have CASMO-3 calculate a value of kif using that restart file with the isotopics in the spent fuel rack geometry model. This value of kinf will be used for the reactivity equivalency step (Step 5).

5) Re-run CASMO-3 iterating on the B-10 concentration to replace the fission products and minor actinides until a value is found where the generated value of kinf matches the original value of kin,.

6) Record the final isotopic concentrations from that final .CASMO-3 run. These isotopes will be used to model that node in KENO-V.a. Repeat steps 3-5 for each node bumup. The end product will be 10 sets of isotopic and B-10 concentrations for the 10 axial nodes in KENO-V.a.

Note that this is a reactivity equivalencing process which uses B10 to adjust the equivalent assembly reactivity to the base assembly reactivity. Therefore, the process is not dependent upon having the exact isotopic number density for 016 and is self correcting in the sense that the B10 concentration is adjusted to obtain the correct assembly reactivity by definition. Small variations in the 016 number density can be obtained due the thermal expansion adjustment in the CASMO-3 depletion runs. The process used here provides an easy verification that the correct assembly reactivity is obtained.

In accordance with NRC directives (Reference [7]), an additional penalty is taken when burnup credit is applied.

This penalty is 5% of the difference between the reactivity of the assembly when fresh and the reactivity of the assembly at the desired burnup point. This penalty, then, is specific to assembly enrichment and the desired burnup. The values are obtained from the CASMO-3 depletion of the nominal assembly in core geometry at 700 ppm. The calculated penalties are:

4.54% Fuel: 0 GWD/MTU kcff = 1.32572 15 GWD/MTU kcff= 1.13922 30 GWD/MTU keff = 1.02497 4.00% Fuel: 0 GWD/MTU kcff = 1.29877 24 GWD/MTU k~ff = 1.03531 3.20% Fuel: 0 GWD/MTU koff = 1.24604 15 GWD/MTU kaff = 1.05231 Penalty for 4.54% Fuel at 15 GWD/MTU = 0.05*(1.32572-1.13922) = 0.0093 Penalty for 4.54% Fuel at 30 GWD/MTU = 0.05*(1.32572-1.02497) = 0.0150 Penalty for 4.00% Fuel at 24 GWD/MTU = 0.05*(1.29877-1.03531) = 0.0132 Penalty for 3.20% Fuel at 15 GWD/MTU = 0.05*(1.24604-1.05231) = 0.0097 Even though core conditions are used to estimate the reactivity penalty rather than rack geometry, the estimated uncertainties remain applicable since a conservative additive adjustment is used rather than a statistical combination.

B.1.4 Loading Curve Generation Method The general objective of the loading curve is to determine the physical requirements for which assemblies of a given initial enrichment loading and assembly average burnup can be stored in a given storage rack configuration.

The general process for generating a BUC loading curve is to calculate the KENO-V.a BUC data, based on initial assembly enrichments and various burmups. A set of enrichment and burnup points was established in Section 4.0 for the various loading patterns at selected enrichments (see Table 4-2, Table 4-5, Table 4-8) using the process Page 59

A AR EVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit outlined in the previous section. The intermediate enrichments in Table 4-1, Table 4-4, and Table 4-7 were then developed by linear interpolation between these derived limits. For example, for C-Rack region 1B (the 3-of-4 loading pattern), the enrichment/burnup values were determined by interpolating between the 4.54% fuel at 15 GWD/MTU and 2.50% fuel at 0 GWD/MTU. For region 1C (the 4-of-4, or fully loaded section), the values were determined by interpolating between 1.80% at 0 GWD/MTU, 3.20% at 15 GWD/MTU, 4.00% -at 24 GWD/MTU, and 4.54% at 30 GWD/MTU. For the E-rack, the values were determined by interpolating between 4.54% at 15 GWD/MTU and 2.5% at 0 GWD/MTU.

Also, for implementing as Technical Specifications, a 10% measurement uncertainty is added to all burnup values in the tables. This conservatively bounds the differences that may occur between the average two-dimensional assembly burnup values as determined by the incore monitoring system and the actual burmup.

The loading limits are as shown in Table 4-1, Table 4-4, and Table 4-7.

B.2 Legacy Fuel Storage Several assemblies are legacy fuel from very early cycles. A number of assemblies may have had lumped burnable absorber pins in empty tubes and other assemblies may have had fuel rods replaced with either stainless steel rods or empty pin cells. These fuel configurations were examined in Section B. 1.3 of Reference [9]. The presence of guide tubes for burnable poison pins or empty pin cells may result in a reactivity increase as much as 0.005 Ak. The effect of actinide buildup due to the presence of burnable poisons during depletion and subsequent burnable poison removal is small and estimated by an additional 0.005 Ak penalty. The continued storage of batches A through K in Region 1 is acceptable, if a 1.0 GWD/MTU penalty is subtracted from the burnup as indicated by the core monitoring system to meet the requirements set forth in Section 6.0. This was determined by examining fuel depletions of similar enrichment which indicates that this burnup penalty covers the approximately 0.01 Ak reactivity bias of these assemblies.

Page 60

A AREVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit APPENDIX C: KENO.V-A TOLERANCE CALCULATIONS This appendix includes the details of the system and tolerance studies that define the additional data for the K 9 5 /95 equation.

C.1 System Bias (Aksys and asys)

These are the calculations that define the biases on the reactivity calculations that are not considered random variation. These effects that could lead to such biases are fuel rack swelling, rack interaction effects, the use of NFBC in required empty cells, modified fuel assemblies, and pool temperature. These effects are represented in the K 95/95 equation by Aksys and asy, (see Section 3.5.1).

C.1.1 Fuel Rack Swelling As discussed in Section 3.3.5 (Swelling Model), persistent, major voiding of the flux trap region is not expected.

However, a scenario in which voiding could occur along the height of a cell's absorber plates' gap or plenum was hypothesized. In this scenario, a plugged vent hole in a fuel cell occurs, with a second defect lower in the same fuel box (such as a crack in a weld), which could allow water to exit the annular region as a bubble expanded in the plenum. The total width of the voided annular region is 0.040 inches, because the absorber cavity is nominally 0.250 inches wide and the absorber material is nominally 0.210 inches wide. In this case, swelling of the cell walls would not be expected, but a pocket of gas could displace the water in the upper regions of the fuel box that typically surrounds the absorber plate. Given the required assumptions for this scenario to occur, it is considered improbable. To assess the impact of this scenario, a sensitivity study was examined where water is displaced between depleted Carborundum' plates and the stainless steel walls for a small number of cells. This would theoretically occur only in a cell that accumulated gas or swelled due to oxidation of the material.

Models were created to examine this for one voided cell in an 8x8 rack, and for two adjacent cells both experiencing displaced water.

Table C-1: Rack C Voiding Effects Dissolved Description Boron, klff 7k ppm Base Case, no voiding, 4-of-4 850 0.8329 0.0006 Base Case, no voiding, 4-of-4 0 0.9312 0.0006 One Voided Cell 850 0.8316 0.0006 One Voided Cell 0 0.9251 0.0007 Two adjacent Voided Cells 850 0.8330 0.0006 Two adjacent Voided Cells 0 0.9238 0.0006 It is seen that the voided cell cases do not give statistically different values, usually being actually slightly lower than the non-void base case. As such, unless voiding is anticipated to be a wide spread problem rather than occurring in isolated cells, it does not affect the conclusions of this analysis.

Section 3.3.5 contains further information on the swelling model.

Page 61

A AREVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit C.1.2 Rack Interaction Models This section describes the rack interface models to support the results presented in Section 4.5. The Region 2 rack geometry is needed to perform a rack interface model and is more complicated than either of the racks in Region

1. The model must split the rack into unit arrays that in this case requires a portion of the fabricated rack cell to be modeled in the inter-box cell. The cut off portion encompasses a large portion of the Boraflex gap region (hence forth referred to as the gap region).

The fabricated box model is the simplest because it is simply a stainless steel box with a smallslice of the gap region. Table C-2 lists the dimensions in the model.

Table C-2: Fabricated Box Model Dimensions Component in Cumulative cm 1/2 cm Cell ID 9.00 9.00 22.860 11.43 Box Wall thickness 0.075 9.15 23.241 11.6205 Gap/wrapper 0.010 9.17 23.292 11.6459 Gap length 7.400 7.400 18.796 9.398 Gap/wrap box 1 horizontal length - 9.17 23.2918 11.6459 Gap/wrap box 1 vertical length 9.15 23.241 11.6205 The inter-box is a bit more complicated due to the need to have different units for the gap/wrapper on each side.

Table C-3 lists the dimensions for the model.

Table C-3: Inter-Box Model Dimensions Component in Cumulative cm 1/2 cm Cell ID 9.066 9.066 23.028 11.51382 Wrapper 0.020 9.106 23.129 11.56462 Gap 0.022 9.15 23.241 11.6205 wrapper/gap 0.010 9.17 23.292 11.6459 gap length - 7.400 18.796 9.398 gap+wrapper 7.44 18.898 9.4488 gap/wrap box I horizontal length 9.17 23.2918 11.6459 gap/wrap box I vertical length 9.066 23.02764 11.51382 This arrangement works fine for an infinite rack array. However, this model is being developed for an evaluation of the possible coupling between the Region 1 and Region 2 racks. Thus, edge units must be developed to provide a finite rack array. For this evaluation it is assumed that the Region 2 rack will reside to the left of the Region 1 rack. Thus, right edges are needed to terminate the rack. Figure C-I illustrates an expanded section of the KENO-V.a model of the fabricated and inter-boxes at the edge of the rack.

Page 62

A AR EVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit Figure C-I: Sketch of KENO-V.a Model at Edge of Region 2 Racks C.1.2.1 C Rack Interaction Combined Models The 'C' rack interaction model uses the swelling model for the 'C' rack and the Region 2 model discussed previously. The nominal separation distance between the two regions is 2.43" +/- 0.25" that gives a minimum separation of 2.18" (5.5372 cm). The 'C' rack interaction distance uses the minimum separation distance in the model of the two racks. The 'C' rack is modeled as a lOx 10 array in a 2-of-4 loading pattern. The model extends 102.5" in the y direction based upon the 10.25" pitch. The Region 2 rack is modeled as an 1 Wxl0 array with a y distance of 100.87" based upon the 9.17" pitch. To provide common y-direction values for the joint array, a 1.63" (4.1402 cm) water gap is placed at the top of the array. This is slightly larger than the -1.438" gap between two modules; however, it is within the 0.25" uncertainty in placement. Figure C-2 provides a sketch of the model (note only 2 of the 10 axial rows are shown to enable enlargement of the sketch). The two separated racks have a 12" water reflector in the x and z directions. The y-direction has a periodic condition to simulate an infinite rack in that dimension.

Page 63

A AR EVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit Figure C-2: Sketch of a Portion of the 'C'-Region 2 Model C.1.2.2 E Rack Interaction Combined Models The 'E' rack interaction model uses the maximum swelling model for the 'E' rack and the Region 2 model discussed previously. The nominal separation distance between the two regions is 3.58" +/- 0.25". The 'E' rack interaction distance uses the nominal separation distance in the model of the two racks. The 'E' rack is modeled as a 5x10 array in the loading pattern defined in Section 4.3 The model extends 53.45" in the y direction based upon the 10.69" y-pitch. The Region 2 rack is modeled as a 6x7 array with a y distance of 55.02" based upon the 9.17" pitch. To provide common y-direction values for the joint array, a 1.57" (3.9878) water gap is split over the top and bottom of the 'E' rack. Figure C-3 provides a sketch of the model (note only 2 of the axial rows are shown to enable enlargement of the sketch). The two separated racks have a 12" water reflectcr on all sides.

Note the lack of top/bottom plates in the Region 2 model is assumed to have an insignificant effect on results.

Page 64

A AR EVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit Figure C-3: Sketch of a Portion of the Region 1E -Region 2 Model C.1.3 NFBC Models NFBC, as described in Section B. 1.2 of Reference [9], were analyzed for storage in the 3-of-4 and 4-of-4 areas of the rack, and the results are shown in Table 4-10 and Table 4-11 of this document.

C.1.4 Moderator Temperature Effects Section B.1.4 of Reference [9] examined moderator temperature effects and saw that the pool has a negative moderator coefficient, i.e., reactivity is highest at low temperatures. In examining the model variations at very low moderator temperatures, a very small difference was seen between 320 F and maximum density at 390 F, where water density varies by 0.000096 g/cc. This difference was included as a tolerance. In performing this analysis, Reference [9] remains valid to identify the limiting water density for this rack as 1.0 g/cc and the bias difference identified between 320 F and 390 F is not significant. This is consistent with typical practice to model maximum moderation at 1.0 g/cc when reactivity peaks at cold temperatures. This approach was used in this analysis.

Page 65

A AREVA Document No.: ANP-2858-0O01 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit C.2 Statistical Tolerance Studies for Akto, and O'toI This section describes the details of the random varying parameters that contribute to Akto1 and a o1. When multiple conditions are run for the same tolerance, the maximum positive value is used and is in bold face. The positive values of these tolerances are listed in the summary tables in Section 3.5.3.

C.2.1 Planar Enrichment and Assembly Placement The planar enrichment study was documented in Section B.2.1 of Reference [9], and showed that the average enrichment model for the 4-of-4 rack loading is conservative, and remains applicable for this application.

C.2.2 Rack Tolerance Studies For the tolerance calculations, the four-of-four loading configuration bounds the three-of-four loading configuration. as shown in Tables B- 12 and B- 13 of Reference [9]. The detailed results of the rack tolerance calculations are listed in Table C-4 for the 'C' Rack and C-5 for the 'E' Rack using nominal rack geometry (no swelling).

Table C-4: Rack 'C' Nominal Tolerance Results Description of Case ] k. I a [ Ak to base Base C Rack 4-of-4 1.1666 0.0001 -

Inner Box Wall ID -0.12 1.1605 0.0001 -0.0061 Inner Box Wall Thickness Inside +0.01 1.1641 0.0001 -0.0025 Inner Box Wall Thickness Inside -0.01 1.1690 0.0001 0.0024 Inner Box Wall Thickness Outside +0.01 1.1654 0.0001 -0.0012 Inner Box Wall Thickness Outside -0.01 1.1677 0.0001 0.0011 Absorber Thickness +0.035 1.1769 0.0001 0.0103 Absorber Thickness -0.02 1.1610 0.0001 -0.0056 Absorber Width + 0.05 1.1669 0.0001 0.0003 Absorber Width -0.01 1.1665 0.0001 -0.0001 Outer Box Wall Thickness Inside +0.01 1.1655 0.0001 -0.0011 Outer Box Wall Thickness Inside -0.01 1.1677 0.0001 0.0011 Outer Box Wall Thickness Outside +0.01 1.1655 0.0001 -0.0011 Outer Box Wall Thickness Outside -0.01 1.1678 0.0001 0.0012 Outer Box OD + 0.12 1.1654 0.0001 -0.0012 Pitch +0.04" 1.1605 0.0001 -0.0061 Pitch -0.04" 1.1732 0.0001 0.0,066 SS rod OD -0.005 1.1665 0.0001 -0.0001 Page 66

A AR EVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit Table C-5: Rack 'E' Nominal Tolerance Results Description of Case [ kcf I I Ak to base Base E Rack 4-of-4 1.0729 0.0002 Inner Box Wall ID -0.12 1.0671 0.0002 -0.0058 Inner Box Wall Thickness Inside +0.01 1.0710 0.0002 -0.0019 Inner Box Wall Thickness Inside -0.01 1.0746 0.0002 0.0(117 Inner Box Wall Thickness Outside +0.01 1.0724 0.0002 -0.0005 Inner Box Wall Thickness Outside -0.01 1.0738 0.0002 0.0009 Absorber Thickness +0.035 1.0803 0.0002 0.0074 Absorber Thickness -0.02 1.0690 0.0002 -0.0039 Absorber Width + 0.05 1.0728 0.0002 -0.0001 Absorber Width -0.01 1.0727 0.0002 -0.0002 Outer Box Wall Thickness Inside +0.01 1.0722 0.0002 -0.0007 Outer Box Wall Thickness Inside -0.01 1.0737 0.0002 0.0008 Outer Box Wall Thickness Outside +0.01 1.0722 0.0002 -0.0007 Outer Box Wall Thickness Outside -0.01 1.0735 0.0002 0.01)06 Outer Box OD + 0.12 1.0721 0.0002 -0.0008 Pitch +0.04" 1.0678 0.0002 -0.0051 Pitch -0.04" 1.0779 0.0002 0.0050 SS rod OD +0.005 1.0726 0.0002 -0.0003 SS rod OD -0.005 1.0728 0.0002 -0.0001 C.2.3 Fuel Assembly Tolerance Results The results of the assembly tolerance calculations are listed in Table C-6 for the 'C' Rack and Table C-7 for the

'E' Rack using nominal rack geometry (no swelling).

Table C-6: 'C' Rack Nominal Fuel Tolerances Description ken [ ak I Ak to base Base C Rack 4-of-4 1.1666 0.0001 -

Off-Center 1.1701 0.0001 0.0036 Enrichment +0.05 wt% 1.1688 0.0001 0.0022 Enrichment -0.05 wt% 1.1643 0.0001 -0.0023 Theoretical Density +1.5% 1.1677 0.0001 0.0011 Theoretical Density -1.5% 1.1654 0.0001 -0.0012 Pellet OD +0.0005" 1.1666 0.0001 0.0000 Pellet OD -0.0005" 1.1668 0.0001 0.0002 Clad ID +0.0015" 1.1669 0.0001 0.0003 Clad ID -0.0015" 1.1660 0.0001 -0.0006 Clad OD +0.002" 1.1650 0.0001 -0.0016 Clad OD -0.002" 1.1683 0.0001 0.0017 Instrument Tube ID +0.0015" 1.1664 0.0001 -0.0002 Instrument Tube ID -0.0015" 1.1665 0.0001 -0.0001 Instrument Tube OD +0.002" 1.1665 0.0001 -0.0001 Instrument Tube OD -0.002" 1.1664 0.0001 -0.0002 Page 67

A AREVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit Table C-7: 'E' Rack Nominal Fuel Tolerances Description keff J rk Ak to base Base E Rack 4-of-4 1.0729 0.0002 -

Off-Center 1.1020 0.0002 0.0252 Enrichment +0.05 wt% 1.0748 0.0002 0.0019 Enrichment -0.05 wt% 1.0709 0.0002 -0.0020 Theoretical Density +1.5% 1.0741 0.0002 0.0012 Theoretical Density -1.5% 1.0716 0.0002 -0.0013 Pellet OD +0.0005" 1.0730 0.0002 0.0001 Pellet OD -0.0005" 1.0729 0.0002 0.0000 Clad ID +0.0015" 1.0736 0.0002 0.0007 Clad ID -0.0015" 1.0725 0.0002 -0.0004 Clad OD +0.002" 1.0708 0.0002 -0.0021 Clad OD -0.002" 1.0751 0.0002 0.0022 Instrument Tube ID +0.0015" 1.0730 0.0002 0.0001 Instrument Tube ID -0.0015" 1.0730 0.0002 0.0001 Instrument Tube OD +0.002" 1.0727 0.0002 -0.0002 Instrument Tube OD -0.002" 1.0727 0.0002 -0.0002 Page 68

A AR EVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit APPENDIX D: SPACER GRID, FUEL ROD, AND GUIDE BAR EFFECTS D.1 Spacer Grids Criticality safety has been ensured in spent fuel racks by performing analyses using such codes as KENO-V.a.

The analyses model fuel assemblies located inside rack storage cells. It has been a typical practice to ignore spacer grids while modeling the fuel assemblies. This has been considered conservative since not modeling them replaces a weak poison (the metal of the spacer grid) with a moderator (water). The question has been asked as to whether this assumption is also valid for borated water, since the spacer grid would then be replaced with a material containing a neutron poison. This section examines this issue for the Palisades spent fuel rack.

The analysis here will start with the KENO-V.a model developed for the 'C' rack. The model will be modified to include the effects of spacer grids. This will be done in three ways.

1. The first will be to smear the mass of the grids over the length of the fuel region in the moderator within the fuel assembly. (Smeared Grid model)

2. The second will be to increase the diameter of the fuel pins to add a mass of zirconium equal to the spacer grids (hence, displace an equal volume of water as do the spacer grids). (Thick Clad model)

3. The third method will model the grids at their respective axial locations. The reactivity change from the 'no-grid' cases will be determined, and a decision made as to whether the exclusion of spacer grids is a conservative or non-conservative assumption. (Explicit model)

The following situations are modeled:

1) The 2-of-4 (i.e., checkerboard) arrangement of fuel, no boron in the Carborundum neutron absorber plates, no dissolved boron

2) A 3-of-4 arrangement of fuel, no boron in the Carborundum neutron absorber plates, no dissolved boron.

3) A 4-of-4 (i.e., fully loaded) arrangement of fuel, no boron in the Carborundum neutron absorber plates, no dissolved boron

4) A 4-of-4 (i.e., fully loaded) arrangement of fuel, no boron in the Carborundum neutron absorber plates, at 850, 1720, and 2550 ppm dissolved boron.

5) A 4-of-4 arrangement, with 10% of the boron in the Carborundum neutron absorber plates, remaining, plus 850, 1720, and 2550 ppm of dissolved boron.

Each grid weighs 1.08 kg, and that there are a total of 10 grids. Nine spacer grids are in the active fuel region, the top most grid being above the fuel stack height of 336.81 cm.

The results of the analysis is shown in Table D-1 and demonstrates that it is conservative (or equivalent) not to model the spacer grids in KENO-V.a for criticality safety analyses. This is valid whether dissolved boron is present or not, or whether residual boron is present in the Carborundum or not.

Page 69

A AR EVA - Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit Table D-1: Spacer Grid Results Case Model Method Residual Boron- Soluble Boron keff Description Content in (ppm)

Carborundum 2-of-4 No grids No boron 0 0.8646 +/- 0.0005 Smeared grids No boron 0 0.8581 +/- 0.0005 Explicit No boron 0 0.8591 +/- 0.0005 3-of-4 No grids No boron 0 1.0556 +/- 0.0005 Smeared grids No boron 0 1.0493 +/- 0.0005 Explicit No boron 0 1.0517 +/- 0.0005 4-of-4 No grids No boron 0 1.1662 +/- 0.0004 Smeared grids No boron 0 1.1617 +/- 0.0004 Explicit No boron 0 1.1618 +/- 0.0004 4-of-4 No grids No boron 850 1.0480 +/- 0.0004 Smeared grids No boron 850 1.0441 +/- 0.0004 Thick Clad No boron 850 1.045:2 +/- 0.0004 No grids No boron 1720 0.9552 +/- 0.0005 Smeared grids No boron 1720 0.9529 +/- 0.0004 Thick Clad No boron 1720 0.9535 +/- 0.0004 No grids No boron 2550 0.8837 +/- 0.0004 Smeared grids No boron 2550 0.8833 +/- 0.0003 Thick Clad No boron 2550 0.8837 +/- 0.0003 4-of-4 No grids 10% Boron remaining 850 0.9188 +/- 0.0005 Smeared grids 10% Boron remaining 850 0.9119 +/- 0.0004 Thick Clad 10% Boron remaining 850 0.9136 +/- 0.0004 Explicit 10% Boron remaining 850 0.9146 +/- 0.0004 4-of-4 No grids 10% Boron remaining 1720 0.8521 +/- 0.0004 Smeared grids 10% Boron remaining 1720 0.8479 +/- 0.0004 Page 70

A AREVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit Thick Clad 10% Boron remaining 1720 0.8486 +/- 0.0004 Explicit 10% Boron remaining 1720 0.8487 +/- 0.0004 4-of-4 No grids 10% Boron remaining 2550 0.7989 +/- 0.0004 Smeared grids 10% Boron remaining 2550 0.7963 +/- 0.0004 Thick Clad 10% Boron remaining 2550 0.7970 +/- 0.0004 Explicit 10% Boron remaining 2550 0.7974 +/- 0.0004 D.2 Fuel Rod Pitch Tolerance The average rod pitch for the assembly is based on the value of 0.550 inches for the inner cells combined with the fuel rod pitch of 0.494 inches for the outer row of cells. Since the majority of the cells are at 0.550 inches, it will conservatively be assumed that all cells are at a pitch of 0.550 inches. There is no actual tolerance on the fuel rod pitch, only minimum gaps for an individual rod.

Even though the fuel rod pitch of 0.550 inches is considered the maximum possible, a sensitivity study was conducted. A variation of 0.005 inches about an assembly envelope of 8.250 inches resulted in:

nominal case: k-eff= 1.0729 +/- 0.0002 increase pitch: k-eff= 1.0732+!- 0.0002 decrease pitch: k-eff= 1.0724 +/- 0.0002 The maximum Ak is for the pitch increase is 0.0003. This demonstrates the insignificance of this effect.

D.3 Guide Bars Eight guide bars are located at the outer edges of the assembly. The guide bars are irregular shaped pieces of solid Zircaloy-4. Two bars are located on each side of the fuel assembly. Figure D-1 provides a sketch of the cross section of the guide bar. The guide bars were represented in KENO-V.a by determining a.minimum equivalent rectangular cross section, therefore adding more water to the under moderated fuel assembly. The base model uses a cross sectional area of 0.1586 in2 based upon an assumption that less Zr (more water) produces conservative results.

A series of cases was run to evaluate the rectangular guide bar model, which demonstrated that the equivalent rectangular cross section model was statistically equivalent to cases where the triangular cut-outs were explicitly modeled, Based on this evaluation, no further tolerance study was performed for the guide bars because of the undermoderated nature of the model.

Page 71

A AR EVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit Figure D-1: Sketch of Guide Bar (Figure is not essential - only shape is important)

Page 72

A AREVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit APPENDIX E: RACK C AND E KENO-V.A INPUT DECKS AND CASMO-3 DEPLETION INPUT DECK E.1 Type 'C' Rack, base model

=csas25 parm=size=400000 mark CE 15x15 fa,assy 44groupndf5 latticecell uo2 1 0.96 293 92235 4.54 92238 95.46 end

'm5 modeled as pure Zirc zr 2 1.0 293 end h2o 3 1.0 293 end

'arbm-bormod 1. 0 1 1 0 0 5000 100 3 850.0e-6 293 end h2o 4 1.0 293 end

'arbm-bormod 1. 0 1 1 0 0 5000 100 4 850.0e-6 293 end zr 5 1.0 293 end

'carbon remaining in absorber w only C density c 6 den= 0.2720 1.0 293 end

'arbm-deplabs 0.34986 3 1 0 0 6012 77.75 5010 3.75 5011 18.50

' 6 1.0 293 end he 7 1.0 2 93 end ss304 8 1.0 2 93 end h2o 9 1.0 2 93 end

'arbm-bormod 1.0 1 1 0 0 5000 100 9 850.0e-6 293 end arbm-nl 10.22632 9 0 0 0 92235 1.98064400 8016 12.18339000 92236 0.15551352 92238 85.30581000 94239 0.30525711 94240 0.04781651 94241 0.01942911 62149 0.00019787 5010 0.00195354 10 1.0 293 end arbm-n2 10.16979 9 0 0 0 92235 1.58685300 8016 12.25111100 92236 0.22658973 92238 85.39639000 94239 0.39949101 94240 0.09179883 94241 0.04505983 62149 0.00021248 5010 0.00249775 11 1.0 293 end arbm-n3 10.14612 9 0 0 0 92235 1.44344000 8016 12.27970000 92236 0.25164000 92238 85.43046000 94239 0.42521432 94240 0.10895521 94241 0.05765310 62149 0.00021730 5010 0.00272517 12 1.0 293 end arbm-n4 10.14540 9 0 0 0 92235 1.44244200 8016 12.28057000 92236 0.25234892 92238 85.42522000 94239 0.42796360 94240 0.10993850 94241 0.05857248 62149 0.00021963 5010 0.00274357 13 1.0 293 end arbm-n5 10.14849 9 0 0 0 92235 1.46418000 8016 12.27682000 92236 0.24929510 92238 85.41277300 94239 0.42796203 94240 0.10846740 94241 0.05756386 62149 0.00022214 5010 0.00272973 14 1.0 293 end arbm-n6 10.14827 9 0 0 0 92235 1.46703500 8016 12.27709000 92236 0.24954812 92238 85.40414000 94239 0.43151122 94240 0.10927852 94241 0.05842377 62149 0.00022549 5010 0.00274814 15 1.0 293 end arbm-n7 10.17921 9 0 0 0 92235 1.66093820 8016 12.23978000 92236 0.21593593 92238 85.35505000 94239 0.39608380 94240 0.08531319 94241 0.04421127 62149 0.00022297 5010 0.00246887 16 1.0 293 end arbm-n8 10.23130 9 0 0 0 92235 2.02735420 8016 12.17746100 Page 73

A AREVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit 92236 0.14924430 92238 85.27360000 94239 0.30533722 94240 0.04622987 94241 0.01861205 62149 0.00020659 5010 0.00195136 17 1.0 293 end arbm-n9 10.25018 9 0 0 0 92235 2.17649100 8016 12.15503000 92236 0.12162550 92238 85.23914000 94239 0.26224893 94240 0.03286853 94241 0.01064050 62149 0.00019944 5010 0.00176079 18 1.0 293 end arbm-nlO 10.27812 9 0 0 0 92235 2.41716430 8016 12.12199000 92236 0.07612709 92238 85.19009000 94239 0.17579080 94240 0.01425901 94241 0.00293903 62149 0.00018339 5010 0.00145416 19 1.0 293 end arbm-nf 10.17609 9 0 0 0 92235 1.63552920 8016 12.24353000 92236 0.21934110 92238 85.37229100 94239 0.39501553 94240 0.08653247 94241 0.04506852 62149 0.00021883 5010 0.00247719 20 1.0 293 end end comp squarepitch 1.3970 0.9144 1 3 1.0592 2 0.9322 7 end more data res=10 cylinder 0.4572 dan(10)=0.23801701 res=ll cylinder 0.4572 dan(ll)=0.23801701 res=12 cylinder 0.4572 dan(12)=0.23801701 res=13 cylinder 0.4572 dan(13)=0.23801701 res=14 cylinder 0.4572 dan(14'=0.23801701 res=15 cylinder 0.4572 dan (15) =0.23801701 res=16 cylinder 0.4572 dan (16) =0.23801701 res=17 cylinder 0.4572 dan (17) =0.23801701 res=18 cylinder 0.4572 dan (18)=0.23801701 res=19 cylinder 0.4572 dan (19) =0.23801701 res=20 cylinder 0.4572 dan (20) =0.23801701 end more data Palisades 15x15 read parm tme=100 gen=5075 nsk=75 run=yes npg=5000 nub=yes end parm read geom unit 1

'fuel pin cell fresh 4.54 wt%

cylinder 1 1 0.4572 336.81 0.0 cylinder 7 1 0.4661 336.81 0.0 cylinder 2 1 0.5296 336.81 0.0 cuboid 3 1 4pO. 6 9 8 5 336.81 0.0 unit 2

'fuel pin cell 3.20 wt% at 15gwt/mtu cylinder 10 1 0.4572 18.71 0.0 cylinder 11 1 0.4572 37.42 0.0 cylinder 12 1 0.4572 56.13 0.0 cylinder 13 1 0.4572 112.28 0.0 cylinder 14 1 0.4572 168.44 0.0 cylinder 15 1 0.4572 224.53 0.0 cylinder 16 1 0.4572 280.68 0.0 cylinder 17 1 0.4572 299.39 0.0 cylinder 18 1 0.4572 318.10 0.0 cylinder 19 1 0.4572 336.81 0.0 Page 74

A AREVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit cylinder 7 1 0.4661 336.81 0.0 cylinder 2 1 0.5296 336.81 0.0 cuboid 3 1 4 pO.6985 336.81 0.0 unit 60

'instrument tube cell cylinder 4 1 0.4661 336.81 0.0 cylinder 5 1 0.5296 336.81 0.0 cuboid 4 1 4 pO. 6 9 8 5 336.81 0.0 unit 70

'Tie Bar Top cuboid 2 1 2pO.4757 0.6985 -0.37715 336.81 0.0 cuboid 4 1 4pO.6985 336.81 0.0 unit 71

'Tie Bar Bottom cuboid 2 1 2pO.4757 0.37715 -0.6985 336.81 0.0 cuboid 4 1 4 pO. 6 9 8 5 336.81 0.0 unit 72

'Tie Bar Left cuboid 2 1 0.37715 -0.6985 2pO.4757 336.81 0.0 cuboid 4 1 4pO.6985 336.81 0.0 unit 73

'Tie Bar Right cuboid 2 1 0.6985 -0.37715 2pO.4757 336.81 0.0 cuboid 4 1 4pO.6985 336.81 0.0 unit 80

'Absorber slot Horizontal (+X) Top cuboid 6 1 2plO.49 2pO.2667 336.79 0.0

'replicate 4 1 0.00 0.00 0.0508 0.0508 0.0 0.0 1 unit 81

'Absorber slot Horizontal (+X) Bottom cuboid 6 1 2plO.49 2pO.2667 336.79 0.0

'replicate 4 1 0.00 0.00 0.0508 0.0508 0.0 0.0 1 unit 82

'Absorber slot Horizontal (+Y) Left cuboid 6 1 2p0.2667 2 plO. 4 9 336.79 0.0

'replicate 4 1 0.0508 0.0508 0.00 0.00 0.0 0.0 1 unit 83

'Absorber slot Horizontal (+Y) Left cuboid 6 1 2pO.2667 2plO.49 336.79 0.0

'replicate 4 1 0.0508 0.0508 0.00 0.00 0.0 0.0 1 unit 85

'Space Cylinder cylinder 8 1 0.3175 336.79 0.0

'cuboid 4 1 0.3175 -0.3175 0.3175 -0.3175 336.79 0.0 Page 75

A AR EVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit unit 90

'15 x 15 fa in rack - 4.54 fresh assembly array 1 -10.4775 -10.4775 0.0 cuboid ,4 1 10.4775 -10.4775 10.4775 -10.4775 336.81 0.0 replicate 4 1 0.3937 0.3937 0.3937 0.3937 0.0 0.0 1 replicate 8 1 0.3175 0.3175 0.3175 0.3175 0.0 0.0 1 replicate 4 1 0.635 0.635 0.635 0.635 0.0 0.0 1

'absorber slot top hole 80 0.0 11.5062 0.01

'absorber slot bottom hole 81 0.0 -11.5062 0.01

'absorber slot left hole 82 -11.5062 ,0.0 0.01

'absorber slot right hole 83 11.5062 0.0 0.01 support top left hole 85 -11.5062 11 .5062 0.01 support top right hole 85 11.5062 11 .5062 0.01

'support bottom right hole 85 11.5062 -11 .5062 0.01

'support bottom left hole 85 -11.5062 -11 .5062 0.01 replicate 8 1 0.3175 0.3: 175 0.3175 0.3175 0.0 0.0 1 replicate 4 1 0.8763 0.8 763 0.8763 0.8763 0.0 0.0 1 unit 91

'15 x 15 fa in rack - 3.20 15gwd/mtu array 2 -10.4775 -10.4775 0.0 cuboid 4 1 10.4775 -10.4775 10.4775 -10.4775 33 6.81 0.0 replicate 4 1 0.3937 0.3937 0.3937 0.3937 0.0 0.0 1 replicate 8 1 0.3175 0.3175 0.3175 0.3175 0.0 0.0 1 replicate 4 1 0.635 0.635 0.635 0.635 0.0 0.0 1

'absorber slot top hole 80 0.0 11.5062 0.01

'absorber 7 slot bottom hole 81 0.0 -11.5062 0.01

'absorber slot left !

hole 82 -11.5062 0.0 0.01

'absorber slot right hole 83 11.5062 0.0 0.01 support top left hole 85 -11.5062 11.5062 0.01 support top right hole 85 11.5062 11.5062 0.01 support bottom right hole 85 11.5062 -11.5062 0.01 support bottom left hole 85 -11.5062 -11.5062 0.01 replicate 8 1 0.3175 0.3175 0.3175 0.3175 0.0 0.0 1 replicate 4 1 0.8763 0.8763 0.8763 0.8763 0.0 0.0 1 Page 76

A ARE VA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit unit 100

'Empty Rack Cell cuboid 4 1 10.4775 -10.4775 10.4775 -10.4775 336.81 0.0 replicate 4 1 0.3937 0.3937 0.3937 0.3937 0.0 0.0 1 replicate 8 1 0.3175 0.3175 0.3175 0.3175 0.0 0.0 1 replicate 4 1 0.635 0.635 0.635 0.635 0.0 0.0 1

'absorber slot top hole 80 0.0 11.5062 0.01

'absorber slot bottom hole 81 0.0 -11.5062 0.01

'absorber slot left hole 82 -11.5062 0.0 0.01

'absorber 7 slot right hole 83 11.5062 0.0 0.01 support top left hole 85 -11.5062 11 .5062 0.01 support top right hole 85 11.5062 11 .5062 0.01 support bottom right hole 85 11.5062 -11 .5062 0.01 support bottom left hole 85 -11.5062 -11 .5062 0.01 replicate 8 1 0.3175 0.3: 175 0.3175 0.3175 0.0 0.0 1 replicate 4 1 0.8763 0.8 763 0.8763 0.8763 0.0 0.0 1 global unit 110

'rack cells array array 20 0.0 0.0 0.0 replicate 4 1 0.0 0.0 0.0 0.0 30.48 30.48 1

'replicate 4 1 30.48 30.48 30.48 30.48 0.0 0.0 1 end geom read array

'4.54 planar average fuel assembly ara=l nux=15 nuy=15 nuz=1 fill 1 1 1 1 71 1 1 1 1 1 71 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 72 1 1 1 1 1 1 1 1 1 1 1 1 1 73 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 60 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 72 1 1 1 1 1 1 1 1 1 1 1 1 1 73 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 I 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 70 1 1 1 1 1 70 1 1 1 1 Page 77

A AREVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit end fill

'fuel assembly 3.20 burned 15gwd/mtu ara=2 nux=15 nuy=15 nuz=l fill 2 2 2 2 71 2 2 2 2 2 71 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 72 2 2 2 2 2 2 2 2 2 2 2 2 2 73 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 60 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 72 2 2 2 2 2 2 2 2 2 2 2 2 2 73 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 70 2 2 2 2 2 70 2 2 2 2 end fill

'fuel assembly rack array ara=20 nux=2 nuy=2 nuz=l fill 90 90 90 90 end fill end array read bounds xyf=periodic +zb=h2o -zb=h2o end bounds end data end Page 78

A AREVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit E.2 Type 'E' Rack, base model

=csas25 parm=size=400000 Palisades,mark CE 15x15 fa,assy, carbon absorber, E rack 44groupndf5 latticecell uo2 1 0.96 293 92235 4.54 92238 95.46 end

'm5 modeled as pure Zirc zr 2 1.0 293 end h2o 3 1.0 293 end

'arbm-bormod 1.0 1 1 0 0 5000 100 3 850.0O e-6 293 end h2o 4 1.0 293 end

'arbm-bormod 1.0 1 1 0 0 5000 100 4 850.0(e-6 293 end zr 5 1.0 293 end

'carbon remain ing in absorber w only C density c 6 den= 0.2720 1.0 293 end he 7 1.0 293 end ss304 8 1.0 293 end h2o 9 1.0 293 end

'arbm-bormod 1.0 1 1 0 0 5000 100 9 850.0e-6 293 end end comp squarepitch 1.3970 0.9144 1 3 1.0592 2 0.9322 7 end more data res=10 cylinder 0.4572 dan(10) =0.23801701 res=1l cylinder 0.4572 dan(ll)=0.23801701 res=12 cylinder 0.4572 dan (12) =0.23801701 res=13 cylinder 0.4572 dan (13)=0.23801701 res=14 cylinder 0.4572 dan (14)=0.23801701 res=15 cylinder 0.4572 dan (15) =0.23801701 res=16 cylinder 0.4572 dan (16) =0.23801701 res=17 cylinder 0.4572 dan (17)=0.23801701 res=18 cylinder 0.4572 dan (18)=0.23801701 res=19 cylinder 0.4572 dan (19) =0.23801701 res=20 cylinder 0.4572 dan (20) =0.23801701 end more data Palisades 15x15 read parm tme=100 gen=5075 nsk=75 run=yes npg=5000 nub=yes end parm read geom unit 1

'fuel pin cell 4.54 wt%

cylinder 1 1 0.4572 336.81 0.0 cylinder 7 1 0.4661 336.81 0.0 cylinder 2 1 0.5296 336.81 0.0 cuboid 3 1 4 pO.6985 336.81 0.0 unit 60

'instrument tube cell cylinder 4 1 0.4661 336.81 0.0 cylinder 5 1 0.5296 336.81 0.0 cuboid 4 1 4 pO.6985 336.81 0.0 unit 70 Page 79

A AR EVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit

'Tie Bar Top cuboid 2 1 2p0.4757 0.6985 -0.37715 336.81 0.0 cuboid 4 1 4p0.6985 336.81 0.0 unit 71

'Tie Bar Bottom cuboid 2 1 2 pO. 4 7 57 0.37715 -0.6985 336.81 0.0 cuboid 4 1 4p 0 . 6 98 5 336.81 0.0 unit 72

'Tie Bar Left cuboid 2 1 0.37715 -0.6985 2pO.4757 336.81 0.0 cuboid 4 1 4pO.6985 336.81 0.0 unit 73

'Tie Bar Right cuboid 2 1 0.6985 -0.37715 2pO.4757 336.81 0.0 cuboid 4 1 4pO.6985 336.81 0.0 unit 80

'Absorber slot Horizontal (+X) Top 2

cuboid 6 1 2plO.49 pO. 2 6 6 7 336.79 0.0 replicate 4 1 0.00 0.00 0.0507 0.0507 0.0 0.0 unit 81

'Absorber slot Horizontal (+X) Bottom cuboid 6 1 2 plO. 4 9 2pO.2667 336.79 0.0 replicate 4 1 0.00 0.00 0.0507 0.0507 0.0 0.0 unit 82

'Absorber slot Horizontal (+Y) Left cuboid 6 1 2pO.2667 2plO.49 336.79 0.0 replicate 4 1 0.0507 0.0507 0.00 0.00 0.0 0.0 unit 83

'Absorber slot Horizontal (+Y) Left cuboid 6 1 2pO.2667 2p10.49 336.79 0.0 replicate 4 1 0.0507 0.0507 0.00 0.00 0.0 0.0 unit 85

'Space Cylinder cylinder 8 1 0.3174 336.79 0.0 cuboid 4 1 0.3174 -0.3174 0.3174 -0.3174 336.79 0.0 unit 90

'15 x 15 fa in rack - 4.54 Planar Average array 1 -10.4775 -10.4775 0.0 cuboid 4 1 10.4775 -10.4775 10.4775 -10.4775 336.81 0.0

'replicate 4 1 0.9525 0.9525 0.9525 0.9525 0.0 0.0 1 replicate 4 1 0.5588 0.5588 0.5588 0.5588 0.0 0.0 1 replicate 4 1 0.3937 0.3937 0.3937 0.3937 0.0 0.0 1 replicate 8 1 0.3175 0.3175 0.3175 0.3175 0.0 0.0 1 replicate 4 1 0.635 0.635 0.635 0.635 0.0 0.0 1

'absorber slot top Page 80

A AREVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit hole 80 0.0 12.065 0.01

'absorber slot bottom hole 81 0.0 -12.065 0.01

'absorber slot left hole 82 -12.065 0.0 0.01

'absorber slot right hole 83 12.065 0.0 0.01 support top left +x hole 85 -11.1252 12.0165 0.01 support top right -x hole 85 11.1252 12.0165 0.01 support bottom right -x hole 85 11.1252 -12.0165 0.01 support bottom left + x hole 85 -11.1252 -12.0165 0.01 support top left -y hole 85 -12.065 11.1252 0.01 support top right -y hole 85 12.065 11.1252 0.01 support bottom right +y hole 85 12.065 -11.1252 0.01 support bottom left +y hole 85 -12.065 -11.1252 0.01 replicate 8 1 0.3175 0.3175 0.3175 0.3175 0.0 0.0 1

'replicat :e 4 1 1.5875 1.5875 0.8763 0.8763 0.0 0.0 1 replicate 4 1 0.8763 0.8763 0.8763 0.8763 0.0 0.0 1 replicate 4 1 0.7112 0.7112 0.0 0.0 0.0 0.0 1 global unit 210

'rack cells array array 20 0.0 0.0 0.0 replicate 4 1 0.0 0.0 0.0 0.0 30.48 30.48 1

'replicate 4 1 0.0 0.0 30.48 30.48 0.0 0.0 1 replicate 4 1 30.48 30.48 30.48 30.48 0.0 0.0 1 end geom read array

'4.54 planar average fuel assembly ara=l nux=15 nuy=15 nuz=l fill 1 1 1 1 71 1 1 1 1 1 71 11 1 1 1 1 1 1 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 72 1 1 1 1 1 1 1 1 1 1 1 1 1 73 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 60 1 1 1111 1 1 1 1 1 1 1 1 1 1 1 1111 1 1 1 1 1 1 1 1 111 1i11 1 72 1 1 1 1 1 1 1i1i 1 11 173 Page 81

AREVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit 1 1 1 1 1 1 1 1 1 11 1 1 11 1 1 1 1 70 1 1 1 1 1 70 1 1 1 1 end fill

'fuel assembly rack array ara=20 nux=l0 nuy=5 nuz=l fill 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 end fill end array read bounds xyf=h2o +zb=h2o -zb=h2o end bounds end data end Page 82

A AR EVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit E.3 CASMO-3 Sample Depletion Deck

Palisades Fuel Assembly @ 4.54 wt% No Gd No LBP

Mirror BCs

Enrichment = 4.54

# of Bp pins (current and previous) = 0, 0

Operating conditions for base case = HFP, 700 ppm

Fuel loading = 443.1 kg U - No Dish, 96.0%TD

Stack height = 132.6 inches

15 = # of pins per row; TIT, *Palisades Assembly 4.54wt% Depletion to 19.56 gwd/mtu TFU=955.4, TMO= 557.7, BOR=700.0 IDE='PAL454' FUM, 0 2 INV, 1.OE-3 1.OE-3 1.30 1.30 50 50 ITP 50,,50,l.lE-5/

BCO, 'MIR' PRE, 142.03 BOX, 6.55/302=100.

CAN, 6.55/302=99.984 47107=0.0082176 47109=0.0077824 *M5 Clad FUE, 1, 10.5216/4.54 SPA, 28.86, , , 6.55/302=100 PIN, 1, 0.2500 0.4500 0.5707/'BOX' 'BOX' 'BOX' *ZR Guide Bar PIN, 2, 0.2500 0.4661 0.5296/'MOD' 'MOD' 'CAN' *IT PIN, 3, 0.4572 0.4661 0.5296/'l' 'AIR' 'CAN' *4.54 FUEL ROD LFU 333303333303333 333333333333333 333333333333333 333333333333333 033333333333330 333333333333333 333333333333333 333333303333333 333333333333333 333333333333333 033333333333330 3 3 3 3 3 3 3 3 3 3 3 ~33 3 3333333333333333 1333333333333333 3 3 3 3 3 3 3 3 3 3 3 3 3 1 333333333333333 33 33 33 33 03 33 33 33.33 33 03 33 33 33 3/'F' 3

LPI 333313333313333 333333333333333 333333333333333 333333333333333 3333333233333333 333333333333333 333333333333333 133333333333331 Page 83

A AR EVA Document No.: ANP-2858-001 AREVA NP Inc.,

an AREVA and Siemens company NON PROPRIETARY Palisades SFP Region 1 Criticality Evaluation with Burnup Credit 333333 333333333 333333 333333333 333333 333333333 333313 3 3 3 3 1 3 3 3 3/'F' PWR, 15 1.397 20.955,,0.46355 0.13335,,1 2 *Full Assembly PDE, 28.381

2565.4 MWT core XEN, 0 THE, 1 LST 1,1i,0 DEP 0.5 1 2 3 4 5 10 15 19.56 /'E' WRE, ALEX BUR STA END Page 84

ML092450684

Text

SUMMARY

SUMMARY

SUMMARY

2.0 INTRODUCTION

SUMMARY

7.0 REFERENCES

Reference:

Navigation menu

Search