ML082240686

WCAP-16541-NP, Revision 2, Spent Fuel Pool Criticality Safety Analysis

ML082240686
Person / Time
Site:	Point Beach
Issue date:	06/30/2008
From:	Anness M, Clarity J, Kucukboyaci V, Marshall W Westinghouse
To:	Office of Nuclear Reactor Regulation
References
NRC 2008-0044 WCAP-16541-NP, Rev 2
Download: ML082240686 (135)

Text

ENCLOSURE 6 FPL ENERGY POINT BEACH, LLC POINT BEACH NUCLEAR PLANT, UNITS I AND 2 LICENSE AMENDMENT REQUEST 247 SPENT FUEL POOL STORAGE CRITICALITY CONTROL NON-PROPRIETARY VERSION WCAP-16541-NP Revision 2 POINT BEACH UNITS I AND 2 SPENT FUEL POOL CRITICALITY SAFETY ANALYSIS DATED JUNE 2008 POINT BEACH NUCLEAR PLANT, UNITS 1 AND 2 125 pages follow

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP Revision 2 Point Beach Units 1 and 2 Spent Fuel Pool Criticality Safety Analysis June 2008 Contributors:

• M.G. Anness

• W.J. Marshall J.B. Clarity V.N. Kucukboyaci Approved by:

• E. W. Jackson, Manager Nuclear Design A

• Electronically approved records are authenticated in the Electronic Document Management System.

Westinghouse Electric Company LLC Nuclear Fuel 4350 Northern Pike Monroeville, PA 15146

©2008 Westinghouse Electric Company LLC All Rights Reserved

SI Westinghouse Non-Proprietary Class 3 1

WCAP-16541-NP, Rev. 2 This page intentionally left blank.

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 Table of Contents Section Title Page 1.0 In tro d u ctio n.........................................................................................................................

1 1.1 Objective........................................................................................................

1 1.2 D e sig n C riteria........................................................................................................

1 1.3 Design Approach 2..............................

2 1.4 M ethodology...................................................................................................

3 1.5 Assum ptions....................................................................................................

7 2.0 D esig n In p u t......................................................................................................................

1 1 2.1 Design Input from Point Beach...........................................

11 2.2 Spent Fuel Pool Storage Configuration Description.........................................

11 2.3 Individual Storage Cell Descriptions...............................

11 2.4 Failed Fuel Rod Storage Basket Description....................................................

11 3.0 A n al y sis.............................................................................................................................

2 1 3.1 KENO Models for the Spent Fuel Pool Storage Configurations..................... 21 3.2 Design Basis Fuel Assembly.............................................................................

23 3.3 M odeling of Axial Burnup Distributions.........................................................

24 3.4 Tolerance / Uncertainty Calculations................................................................

26 3.5 No Soluble Boron 95/95 kl ff Calculational Results.........................................

28 3.6 Soluble Boron..................................................................................................

33 4.0 Summ ary of Results.....................................................................................................

85 4.1 Allowable Storage Configurations..........................................

I5........

85 4.2 Interface Requirem ents in Spent Fuel Pool Storage Racks..................................

86 4.3 Failed Fuel Rod Storage Basket with 5.0 w/o 235U Fuel.......................................

86 4.4 Reconstituted Fuel............................................................................................

86 4.5 E m p ty C e lls...........................................................................................................

8 6 4.6 Non-Fissile Equipm ent.....................................................................................

86 4.7 Total Soluble Boron Requirem ent....................................................................

86 5.0 Com puter Codes Used In Calculation.............................................................................

113 6.0 R e fe ren c e s.......................................................................................................................

1 1 5 Page i of v

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 This page intentionally left blank.

Page ii of v

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 List of Tables Table Title Page Table 1-1 Calculational Results for Cores X Through XXI of the B&W Close Proximity Experiments..... 8 Table 1-2 Calculational Results for Selected Experimental PNL Lattices, Fuel Shipping and Storage C o n fi g u ratio n s........................................................................................................................

9 Table 1-3 Standard Material Compositions Used in Criticality Analysis of the Point Beach Spent Fuel Sto rag e R ack s.............................................................................................

10 Table 2-1 Spent Fuel Pool Dimensions (All dimensions in inches)......................................................

12 Table 2-2 Storage Cell Description (All dimensions in inches)...........................................................

13 Table 3-1 Fuel Assembly Data Used in Criticality Analysis of the Point Beach Spent Fuel Storage Racks 3 7 Table 3-2 Relative Power and Fuel/ Moderator Temperatures for the Axially-Distributed Model.....

38 Table 3-3 Bumup and Initial Enrichment Combinations Used to Determine the Isotopic Number D e n sitie s...............................................................................................................................

3 9 Table 3-4 keff Values for the Tolerance/Uncertainty Cases for the "All-Cell" Storage Configuration...... 40 Table 3-5 keff Values for the Tolerance/Uncertainty Cases for the "l-out-of-4 5.0 w/o Fresh with no IFBA " Storage Configuration........................................................................................

41 Table 3-6 keff Values for the Tolerance/Uncertainty Cases for the "l-out-of-4 4.0 w/o Fresh with IFBA" Storag e C onfig uration..........................................................................................................

42 Table 3-7 Limiting kc1r Values versus Initial Enrichment and Assembly Bumup for the "All-Cell" Storage Configuration (for 0 to 20 Years Decay)........................................................................

43 Table 3-8 Fuel Assembly Bumup versus Initial Enrichment for the "All-Cell" Storage Configuration... 44 Table 3-9 Limiting keff Values for the "All-Cell" Storage Configuration with Fuel Pins in the Guide T u b e s....................................................................................................................................

4 5 Table 3-10 Limiting keff Values for the "All-Cell" Storage Configuration with Fuel Pins in the Guide Tubes: Effect of Split Bum up........................................................................................

46 Table 3-11 Limiting keff Values versus Initial Enrichment and Assembly Burnup for the "l-out-of-4 5.0 w/o Fresh with no IFBA" Storage Configuration (for 0 to 20 Years Decay).............. 47 Table 3-12 Fuel Assembly Bumup versus Initial Enrichment for the "l-out-of-4 5.0 w/o Fresh with no IFB A " Storage C onfiguration..............................................................................

................. 48 Table 3-13 Limiting kefr Values versus Initial Enrichment and Assembly Bumup for the "1-out-of-4 4.0 w/o Fresh with IFBA" Storage Configuration (for 0 to 20 Years Decay)......................

49 Table 3-14 Fuel Assembly Bumup versus Initial Enrichment for the "1-out-of-4 4.0 w/o Fresh with IFBA " Storage Configuration........................................................................................

50 Table 3-15 Limiting kff Values versus Number of IFBA Pins (LOX) Contained in the 4.5 w/o 23'U Fresh Fuel of the "l-out-of-4 4.0 w/o Fresh with IFBA" Storage Configuration.....................

51 Table 3-16 Limiting keff Values versus Number of IFBA Pins (1.OX) Contained in the 5.0 w/o 235U Fresh Fuel of the "l-out-of-4 4.0 w/o Fresh with IFBA" Storage Configuration.....................

52 Table 3-17 Number of IFBAs versus Initial Enrichment for the Fresh Fuel Assembly in the "l-out-of-4 4.0 w/o Fresh with IFBA" Storage Configuration.........................................................

53 Table 3-18 Entire Spent Fuel Pool kff Results for the Interface Configurations...................................

54 Table 3-19 Assembly Loading Requirements at the Interface between Different Storage Configurations 55 Table 3-20 ken. Values for the Failed Fuel Rod Storage Basket with 5.0 w/o 235U Fresh Fuel in the "All-C ell" Storage C onfiguration..................................................................................................

56 Page iii of v

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 Table 3-21 keff Values as a Function of Soluble Boron Concentration for the Spent Fuel Pool with Depleted Fuel Assemblies in the "All-Cell" Storage Configuration...............................

57 Table 3-22 Summary of Bumup Reactivity Uncertainties for the Storage Configurations...................

58 Table 3-23 keff Values for Various Accident Scenarios in the)Spent Fuel Pool.....................................

59 Table 4-1 Fuel Assembly Bumup versus Initial Enrichment for the "All-Cell" Storage Configuration... 87 Table 4-2 Fuel Assembly Bumup versus Initial Enrichment for the "1-out-of-4 5.0 w/o Fresh with no IFBA " Storage Configuration........................................................................................

88 Table 4-3 Fuel Assembly Bumup versus Initial Enrichment for the "l-out-of-4 4.0 w/o Fresh with IFBA" Storage C onfiguration.....................................................................................

I.................... 89 Table 4-4 Number of IFBAs versus Initial Enrichment for the Fresh Fuel Assembly in the "l-out-of-4 4.0 w/o Fresh with IFBA" Storage Configuration................................................................

90 Table 4-5 Assembly Loading Requirements at the Interface between Different Storage Configurations.. 91 Table 5-1 Summary of Computer Codes Used in Point Beach Spent Fuel Pool Criticality Calculations 113 Page iv of v

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 List of Figures Figure Title Page Figure 2-1 Point Beach Spent Fuel Pool Showing Storage Rack Modules..........................................

15 Figure 2-2 Point B each Storage C ell....................................................................................................

17 Figure 2-3 Failed Fuel Rod Storage Basket...........................................................................................

19 Figure 3-1 KENO Plot for the "All-Cell" Storage Configuration.............................................................

61 Figure 3-2 KENO Output Plot for the "l-out-of-4 5.0 w/o Fresh with no IFBA" Storage Configuration63 Figure 3-3 KENO Output Plot for the "1-out-of-4 4.0 w/o Fresh with IFBA" Storage Configuration.... 65 Figure 3-4. Reactivity Comparison of Assemblies with Grids vs. Assemblies with no Grids in the Point B each Spent Fuel Pool M odel........................................................................................

67 Figure 3-5 IFBA Patterns Used in the Point Beach Criticality Analysis............................................

69 Figure 3-6 KENO Output Plot for the Spent Fuel Pool Loaded with the "l-out-of 4 4.0 w/o Fresh with IFBA " Storage Configurations........................................................................................

71 Figure 3-7 KENO Output Plot of the Failed Fuel Rod Storage Basket in the "All-Cell" Storage C onfiguration..............

............. 73 Figure 3-8 Westinghouse 14x14 Standard/422V+ and OFA Fuel Dimensions (OFA dimensions shown in p a ren th esis)..........................................................................................................................

7 5 Figure 3-9 Sketch of Axial Zones Used in Fuel Assembly...................................................................

77 Figure 3-10 Illustration of Axial Bumup Profiles from a Limiting Cycle of Point Beach Unit 1......

79 Figure 3-11 Illustration of Axial Bumup Profiles from a Limiting Cycle of Point Beach Unit 2.......

81 Figure 3-12 Reactivity Comparison of Bounding Axial Burnup Profile vs. the Bumup Profile in the Point Beach Spent Fuel Pool M odel........................................................................................

83 Figure 4-1 Allowable Fuel Assemblies in the "All-Cell" Storage Configuration.................................

93 Figure 4-2 Allowable Fuel Assemblies in the "l-out-of-4 5.0 w/o Fresh with no IFBA" Storage C o n fi g u ration............................................................................................................

.......... 9 5 Figure 4-3 Allowable Fuel Assembly Categories in the "l-out-of-4 4.0 w/o Fresh with IFBA" Storage C o n fig u ratio n.......................................................................................................................

9 7 Figure 4-4 Allowable Interface between "All-Cell" and "l-out-of-4 5.0 w/o Fresh with no IFBA" Storage C onfigurations..................................................................................................

99 Figure 4-5 Allowable Interface between "All-Cell" and "l-out-of-4 4.0 w/o Fresh with IFBA" Storage C o n fi g u ration s....................................................................................................................

10 1 Figure 4-6 Allowable Interface between "l-out-of-4 5.0 w/o Fresh with no IFBA" and "1-out-of-4 4.0 w/o Fresh with IFBA" Storage Configurations..................................................................

103 Figure 4-7 Fuel Assembly Burnup versus Initial Enrichment for the "All Cell" Storage Configuration 1 0 5 Figure 4-8 Fuel Assembly Burnup versus Initial Enrichment for the "l-out-of-4 5.0 w/o Fresh with no IFB A " Storage C onfiguration............................................................................................

107 Figure 4-9 Fuel Assembly Burnup versus Initial Enrichment for the "1 -out-of-4 4.0 w/o Fresh with IFB A " Storage C onfiguration...........................................................................................

109 Figure 4-10 IFBA Requirements for the Fresh Fuel Assembly with Enrichments Greater than 4.0 w/o 235U in the "l-out-of-4 4.0 w/o with IFBA" Storage Configuration..................................

111 Page v of v

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 This page intentionally left blank.

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 1.0 Introduction 1.1 Objective This report presents the results of criticality analyses for the Point Beach spent fuel pool racks with credit for bumup, integral fuel burnable absorber (IFBA), 241Pu decay and soluble boron, where applicable. The primary objectives of this analysis are as follows:

1. To determine the fuel assembly burnup versus initial enrichment limits required for safe storage of fuel assemblies in the "All-Cell," "l-out-of-4 5.0 w/o Fresh With no IFBA," and "l-out-of-4 4.0 w/o Fresh with IFBA" storage configurations with credit for 5, 10, 15, and 20 years of 241Pu decay.

2. To determine the number of IFBA pins versus initial enrichment limits required for safe storage of fuel assemblies in the "1-out-of-4 4.0 w/o Fresh with IFBA" storage configuration.

3. To determine the assembly loading requirements at the interface between storage configurations.

4. To determine the amount of soluble boron required to maintain kerf less than or equal to 0.95 in the spent fuel pool, including all biases and uncertainties, assuming the most limiting plausible reactivity accident.

The methodology used in this analysis for soluble boron credit, and for representing discharged fuel assemblies [

a,, is analogous to that of References I and 2. The methodology for considering fuel assembly and rack uncertainties and tolerances is analogous to that of References 2 and 3. This methodology employs analysis criteria that consider the regulatory guidance for criticality safety analyses provided by the U.S. Nuclear Regulatory Commission (NRC) in Reference 5. References I through 3 were reviewed and approved by the NRC.

1.2 Design Criteria The design criteria are consistent with General Design Criterion (GDC) 62, Reference 4, and considers NRC guidance given in Reference 5. Section 1.3 -describes the analysis methods including a description of the computer codes used to perform the criticality safety analysis. A brief summary of the analysis approach and criteria follows.

1. Determine the fresh and/or spent fuel storage configurations using no soluble boron conditions such that the 95/95 upper tolerance limit value of kqr, including applicable biases and uncertainties, is less than 0.995. [

]a'c Note that the actual NRC kff limit for this condition is less than 1.0 (Reference 6). Therefore, an additional margin of 0.005 Aki-units is included in the analysis results. Note that while the requirement is kff less than 1.0, the analysis' methodology and computational tools provide a greater level of precision to realize this margin.

2. Determine the amount (ppm) of soluble boron necessary to reduce the krff value of all storage configurations by at least 0.05 Akcff units. [

Page I of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2

],C As an example, storage configurations which contain depleted fuel assemblies (and represented by depleted isotopics) are less reactivity-sensitive to changes in soluble boron concentration than a fuel assembly represented by zero burnup and relatively low initial fuel enrichment.

3. Determine the amount of soluble boron necessary to compensate for 5% of the maximum burnup credited in any storage configuration. In addition, determine the amount of soluble boron necessary to account for a reactivity depletion uncertainty of 1.0% Aklff per 30,000 MWD/MTU of credited fuel burnup. [

], C

4. Determine the largest increase in reactivity caused by postulated accidents and the corresponding amount of soluble boron needed to offset this reactivity increase.

The final soluble boron credit (SBC) requirement is determined from the following summation.

SBCTOTAL = SBC95, 95 + SBCRE + SBCpA

Where, SBCTOTAL = total soluble boron credit requirement (ppm)

SBC95195 = soluble boron requirement for 95/95 kff less than or equal to 0.95 (ppm)

SBCRE

= soluble boron required to account for burnup and reactivity uncertainties (ppm)

SBCPA

= soluble boron required to offset accident conditions (ppm)

For purposes of the analysis, minimum burnup limits established for fuel assemblies to be stored in the storage configurations include burnup credit established in a manner that takes into account approximations to the operating history of the fuel assemblies. [

pac 1.3 Design Approach The soluble boron credit methodology provides additional reactivity margin in the spent fuel criticality analysis which may then be used to implement added flexibility in storage criteria and eliminate the need to credit the Boraflex.

The square storage cell pitch modeled for fuel assembly storage configurations is 9.938 inches.

The Boraflex fixed neutron poison is replaced with water in all calculations. No credit is taken for Boraflex in any of the storage configurations. This representation is conservative relative to the physical condition.

The fuel assembly types used for all the analyses are the Westinghouse 14x14 Standard and OFA designs. The most reactive spent fuel pool temperature (with full moderator density of 1.0 g/cm 3)

Page 2 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 is used for each fuel assembly storage configuration such that the analysis results are valid over the nominal spent fuel pool temperature range (500 to 180'F).

The reactivity characteristics of the storage racks were evaluated using infinite lattice analyses; this environment was used in the evaluation of the burnup limits versus initial enrichment as well as the evaluation of physical tolerances and uncertainties. [

aC 1.4 Methodology This section describes the methodology used to assure the criticality safety of the Point Beach spent fuel pool and to define limits placed on fresh and depleted fuel assembly storage configurations. The analysis methodology employs: (1) SCALE-PC, a personal computer version of the SCALE-4.4a code system (deemed applicable for this analysis per Reference 5) with the updated SCALE-4.4a version of the 44 group Evaluated Nuclear Data File (Reference 7),

Version 5 (ENDF/B-V) neutron cross section library, and (2) the two-dimensional PHOENIX-P code (Reference 8) with an Evaluated Nuclear Data File, Version 6 (ENDF/B-VI) neutron cross section library.

SCALE-PC was used for calculations involving infinite arrays for all the storage configurations in the spent fuel pool. [

SCALE-PC, used in both the benchmarking and the fuel assembly storage configurations, includes the control module CSAS25 and the following functional modules: BONAMI, NITAWL-II, and KENO V.a. All references to KENO in this report refer to the KENO V.a module.

The PHOENIX-P code is used for simulation of in-reactor fuel assembly depletion. The following sections describe the application of these codes in more detail.

1.4.1 SCALE-PC The SCALE system was developed for the NRC to satisfy the need for a standardized method of analysis for evaluation of nuclear fuel facilities and shipping package designs. SCALE-PC is a version of the SCALE code system that runs on personal computers.

1.4.2 Validation of SCALE-PC Validation of SCALE-PC for purposes of fuel storage rack analyses is based on the analysis of selected critical experiments from two experimental programs: the Babcock & Wilcox (B&W) experiments in support of Close Proximity Storage of Power Reactor Fuel (Reference 9) and the Pacific Northwest Laboratory (PNL) Program in support of the design of Fuel Shipping and Storage Configurations. References 10 and 11, as well as several of the relevant thermal experiment evaluations in Reference 12 were found to be useful in updating pertinent experimental data for the PNL experiments.

The validation of SCALE-PC was limited to the 44-group library provided with the SCALE-PC version 4.4a package. The 238-group library, which is utilized for the off-nominal temperature cases, is only utilized to determine relative reactivity differences, there are no determinations of absolute reactivity with the 238-group library.

Page 3 of 116

I Westinghouse Non-Proprietary Class 3 R

WCAP-16541-NP, Rev. 2 1 Nineteen experimental configurations were selected from the B&W experimental program; these consisted of the following experimental cores: Core X, the seven measured configurations of Core XI, Cores XII through XXI, and Core XIIIA. These analyses used measured critical data, rather than the extrapolated configurations to a fixed critical water height reported in Reference 9, to avoid introducing possible biases or added uncertainties associated with the extrapolation techniques. In addition to the active fuel region of the core, the full experimental environment, including the dry fuel above the critical water height, was represented explicitly in the analyses.

The B&W group of experimental configurations used variable spacing between individual rod clusters in the nominal 3 x 3 array. In addition, the effects of placing either SS-304 or Borated Aluminum (B/Al) plates of different boron contents in the water channels between rod clusters were measured. Table 1-1 summarizes the results of these analyses performed with both the 44-group and 238-group libraries.

Eleven experimental configurations were selected from the PNL experimental program. These experiments included unpoisoned uniform arrays of fuel pins and 2 x 2 arrays of rod clusters with and without interposed SS-304 or B/Al plates of differing blackness (magnitude of self-shielding corrected neutron absorption cross section). As in the case of the B&W experiments, the full environment of the active fuel region was represented explicitly. Table 1-2 summarizes the results of these analyses performed with both the 44-group and 238-group libraries.

The approach used for the determination of the mean calculational bias and the mean calculational variance is based on Criterion 2 of Reference 14. For a given KENO-calculated value of kerr and associated one sigma uncertainty, the magnitude of k95/95 is computed by the equation below. By this definition, there is a 95 percent confidence level that in 95 percent of similar analyses the validated calculational model will yield a multiplication factor less than k 9 5/9 5.

k 9 5/9 5 :=kkeno + Akias + M95/

'2 +9.C

)KEN

Where, kk,,o is the KENO-calculated multiplication factor Akbi*,

is the mean calculational method bias M 95/95 is the 95/95 multiplier appropriate to the degrees of freedom for the number of validation analyses, and is obtained from the tables of Reference 15 M

is the mean calculational method variance deduced from the validation analyses 2

CrxKo is the square of the KENO standard deviation The equation for the mean calculational methods bias is as follows:

Akbias = -

I-k,

Where, ki is the ih value of the multiplication factor for the validation lattices of interest Page 4 of 116

Westinighouse Non-Proprietary Class 3 WCAP-16541-NP, ReWv 2 The equation for the.mean calculatiohal variance of the relevant validating multiplication factors is as. follows:

n jk 1 -kaje) c, 2

(

n where kave is given by the following equation:

2 by.

o-a is given by the following equation':

E2 G1

.G, is the number of generations.

For purposes of this bias evaluation, the data points of Table 1-1 and Tablet 1-2 are pooled into a single group from the 44-group library calculations. With this.approach, the mean calculational methods bias, Akbiw, and the mean calculational variance, am2, calculated, by the equations given, above, were determined to be [

],' respectively. The magnitude: of M95/95 is obtained :from. Reference 15 forthe:total number of pooled data points, 30.

The magnitude of k95/95 is given. by the following equation for SCALE 4.4a KENO analyses, employing:the 44-group ENDF/B-V neutron cross section library and for analyses where these experiments are a suitable basis for assessing the methods bias and calculational variance:

Based on the above analysis, the mean calculational bias, the mean calculational variance, and the 95/95 confidence level multiplier for the 44-group library were deduced as [

]a.; respectively.

1.4.3 Application to Fuel Storage Pool Calculations As: noted above, the CSAS25 control module was used to execute the functional, modules within SCALE-PC. The CSAS25 control module was used to anayze either infinite arrays of single or multiple storage cells [

]c.. Standard compositions were used in the SCALE-PC analyses for the material design input given in Section 2.0; these data are listed in Page 5.of 116

Westinghouse Non-Propietary Class 3 WCAP-16541-NP, Rev. 2 Table 1-3. Fresh fuel material number densities where calculated within the CSAS25 module of the SCALE package using the input data presented in Table 1-3. For burned fuel representations, the fuel isotopics were derived from the PHOENIX-P code as described below.

1.4.4 The PHOENIX-P Code PHOENIX-P is a two-dimensional, multi-group transport theory lattice code. The multigroup cross sections are based on ENDF/B-VI. PHOENIX-P performs a two-dimensional 70-group nodal flux calculation which couples the individual sub-cell regions (pellet, cladding, and moderator) as well as surrounding rods via a collision probability technique. This 70-group solution is normalized by a coarse-energy-group S4 flux solution derived from a discrete ordinates calculation. [

13,c

]rc PHOENIX-P and its neutron cross section library are employed in the design of initial and reload cores that have supported over 500 reactor-years of operation.

For the purpose of spent fuel criticality analysis calculations, PHOENIX-P is used to generate the detailed fuel nuclide number densities as a function of fuel depletion and initial feed enrichment. Each complete set of fuel nuclides is reduced to a smaller set of depleted fuel nuclides at specific time points after discharge. [

arC

]a.C Page 6 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 1.5 Assumptions Certain major assumptions used throughout this analysis are specified below.

• The Westinghouse 14xl4 Standard fuel was modeled as the design basis fuel assembly to conservatively represent all the depleted fuel assemblies. Westinghouse 14x14 OFA fuel was modeled as the design basis fuel assembly to conservatively represent all fresh fuel assemblies residing in the storage configurations. Although Westinghouse 422V+ fuel is the present fuel design for Point Beach, the Standard fuel is bounding. A Standard fuel assembly is 0.75 inches longer than 422V+ and uses Zirc-4 as the cladding material, which is less absorbent than the ZIRLOTM' 'material used by 422V+. In addition, the 422V+ design contains low-enriched axial fuel blankets, and the Standard fuel design contained active fuel to the top and bottom of the fuel pellet stack.

• All fresh and depleted fuel assembly pellets were conservatively modeled as solid right cylinders and uniformly enriched over the entire length of the fuel stack height. This conservative assumption bounds fuel assembly designs that incorporate lower enrichment blanket or annular pellets.

All of the Boraflex poison material residing in the storage racks was conservatively omitted for this analysis and replaced by water. The stainless steel material encasing the Boraflex was modeled.

a,C The design basis limit for klff at the zero soluble boron condition was conservatively reduced from 1.0 to 0.995 for this analysis.

I Z/RLOTm trademark property of Westinghouse Electric LLC Page 7 of 116

IIWestinghuse Non-Proprietar Cla'ss 3 1 WCAP-1654 1-NP, Rev. 2:

Table 1-1 Calculational Results for Cores X Through XXI of the B&W Close Proximity Experiments 2 Entry indicates metal separating unit assemblies.

Entry indicates spacing between unit assemb lies in units of fuel, rod Pitch.

a,b,c Page Sof 116

Westinghouse Non-PrOprietary Class 3 WCAP-16541-NP, Rev. 2 Table t-2 Calculationall Results for Selected. Experimental PNL Lattices, Fuel Shipping and Storage Configurations a,b,c Page.9.of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 Table 1-3 Standard Material Compositions Used in Criticality Analysis of the Point Beach Spent Fuel Storage Racks Material Element Weight Fraction Zr 0.9824 Zircaloy 4, sn 0.0145 Density = 6.56 g/cm3 Fe 0.0125

@ 9.5KFe 0.0021 Cr 0.0010 SCALE Standard Composition Library Water Density = 1.0 g/cm3 @ 293.15 K SCALE Standard Composition Library Stainless Steel Density = 7.94 g/cm3 @ 293.15 K Fraction of Theoretical Density = 0.975 FEnrichment up to 5.0 wo 235U @ 293.15 K SCALE Standard Composition Library eDensfty = 2.3 g/cm 3 @ 293.15 K Element or Isotope Isotopics E

(atom s/barn/cm2)

[

[

] CC

[

a.c

[

]ac

[

],a 4 Point Beach also uses ZIRLOTM cladding; however, the fuel rod, guide tube, and instrumentation tube claddings are modeled with Zircaloy in this analysis. This is conservative with respect to the Westinghouse ZIRLOTM product, which is a zirconium alloy containing additional elements including niobium. Niobium has a small absorption cross section, which causes more neutron capture in the cladding regions resulting in a lower reactivity. Therefore, this analysis is conservative with respect to fuel assemblies containing ZIRLOTM cladding in fuel rods, guide tubes, and the instrumentation tube.

Page 10 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 2.0 Design Input This section provides a brief description of the Point Beach spent fuel storage racks with the objective of estiblishing a basis for the analytical models used in the criticality analyses described in Section.3.0.

2.1 Design Input from Point Beach Design data related to the Point Beach spent fuel racks were required to develop the KENO models.

2.2 Spent Fuel Pool Storage Configuration Description Point Beach has a single pool divided into north and south halves which are connected through a divider wall. Each pool has an inside dimension of 220.00 inches in the westto east direction and 408.00 inches in the north to south direction. Either seven or eight rack modules, each with 90 to 110 cell locations, occupy the south and north pools, respectively. A cask area (114.61 inches x 117.33 inches) is located in the southwest corner and an elevator area (44.76 inches x 22.84 inches) is located in the southeast comer of the north pool. In the north pool, rack modules are located 4.00 inches from the north wall and 14.82 inches from the south wall, 7.56 inches from the west wall, and 2.88 inches from the east wall. In the south pool, rack modules are located 6.82 inches from the north wall and 12.00 inches from the south wall, 6.19 inches from the west wall, and 4.25 inches from the east wall. Figure 2-1 shows the spent fuel pool and the storage rack modules.

Table 2-1 summarizes the overall geometry data for the Point Beach spent fuel pool.

2.3 Individual Storage Cell Descriptions Point Beach spent fuel pool storage cells are centered on a pitch of 9.938 + 0.093 / -0.010 inches.

Each storage cell consists of an inner stainless steel canister, which has a nominal inside dimension of 8.250 + 0.083 / -0.000 inches and wall thickness 0.093 +/- 0.003-inches. Each Boraflex poison panel isheld in place in an L-shaped shell inside the canister. The dimensions of the Boraflex poison panel are 8.00 + 0.00 / -0.30 inches in width' by 0.100 + 0.000 / -

0.030 inches in thickness. The sheathing panels are included as 0.021 +/- 0.005 inch in thickness and are located at the outside surface of the nominal Boraflex poison panel position. Note that no credit is taken for the presence of the neutron absorbing, Boraflex material in the analysis.

Table 2-2 and Figure 2-2 summarize the storage cell dimensions used for the Point Beach analyses.

2.4 Failed Fuel Rod Storage Basket Description Figure 2-3 shows a sketch of the failed fuel rod storage basket (FFRSB). The FFRSB is designed to accommodate individual spent and/or fresh fuel rods in a fixed array in the spent fuel pool.

The forty-nine tube locations in the FFRSB are in a.7x7 array. Nominal dimensions are not available for this design. The conservative and bounding modeling approach is discussed in Section 3.5.6.

Page 11 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 Table 2-1 Spent Fuel Pool Dimensions (All dimensions in inches)

Parameter Value North Pool Length 408.00 North Pool Width 220.00 South Pool Length 408.00 South Pool Width 220.00 Page 12 of 116

Westing4ouse Non-Proprietary Class 3T WCAP-16541-N]P, ev. 2 Table 2-2 Storage Cell Description (All dimensions in inches)

Parameter Dimension Cell Pitch 9.938 +0.093/-0.010 Cell ID 8.250 +0.083 /-0.000 Cell Wall Thickness 0.093 +/- 0.003 Cell Wall Material SS-304 Absorber5 Width 8.00 +0.00 /-0.30 Absorber Thickness5 0.100 +0.000/-0.030 Sheathing Thickness 0.021 + 0.005 Boraflex is replaced with water Page 13 of 116

I I Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 This page intentionally left blank.

Page 14 of 116

Westinghouse Non-Proprietary ClassJ3 WCAP-16541-NP, Rev. 2

~>~>'>>'

>>':A~'<'

'aPtK>;'a;4 aK4AKKaK>KKKK>a~A>

" Kfr %a4Kt' I~~W

>4<>>

abc at K

P

>K>A 'aK>aaK' KK'KKK4>' >>K<KKKKK AK>""

tat'

>4>'

K" 44<

<'K AK' Pt A

'aK>KK' a<>K'a t &

4$

'KaaAa K'

'Ka 44aK4K at>

a 'a'4.a 4AKKt>QKtiK a>>'

At 44 a>

<'a A

>'Paa'a

'K>

>Kaa

44K4KK4A >>

a 44>'>

'a 44*>'>

aa~>4' at' K>

"K> 444<>

44444 4*4

>4 K>'

a at4

.4>'>

'K>'>' >>

K

<K>

'4 a

>Ka

~>4a

>4K>

4at K a

'a' g>a K~'a ~~Kd'~44

'a>

a K

"a' a

4*44*44*

<K

'at

>4

~p>'4aa~>a K

4 K

at' a>

>4KV K>'>

K K\\

4*

"'a>

4>

a tK'>aK

'at a "' K>'

a>'aaa 4 4 K~

"'K K>' 44 'K"

a AK aaKKaatKa K

a

~

AK>'

K>

K

>4'>a{"

<>4>">

"K

'>aa"a~aK>~ a a">

'a>

>4>'

at'>">>

a

'a>%4Pp4KK

'a>

aaaa<tw a'>

'A

<4"'>>

K>a>aaa K

KK> >' 'a~~'a~~ a4a"K>'K't a>

a a

>a'K*a<a~aa~oaK

'a a

4 v~

~'>'

K

'a'a'a'a4Ka4*aa

'aa a>

<a a >

K> A a

'~>>a>'

a

>>a 44 4,

'>14*">

aK K>

K

>4>'

aaK 44 a

4 aaa

>a a

'aK'>K 4*>>

4>4

' t>

Figure 2-1 Point Beach SpentFuel Pool ShoWing Storage Rack Modules

'nj>

Page 15iof 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 This page intentionally left blank.

Page 16 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 This page intentionally left blank.

Page 18 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 This page intentionally left blank.

Page 20 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 3.0 Analysis 3.1 KENO Models for the Spent Fuel Pool Storage Configurations The Point Beach spent fuel storage racks employ three different fuel assembly storage configurations: "All-Cell," ".-out-of-4

.5.0 w/o Fresh with no IFBA," and "1-out-of-4 4.0 w/o Fresh with IFBA." KENO models of these storage configurations are provided in the following sections. [

The fuel assemblies modeled by KENO represent the Westinghouse 14x14 Standard and OFA designs. Note that the enrichment of fresh fuel pellets is up to5.0 w/o 235 U (nominal) and the U0 2 density is 97.5% of theoretical density. Note that all references to fuel enrichment in this report are nominal enrichment values. The fuel pellets in a fuel rod are modeled as fully enriched right solid cylinders that are 144 inches tall. This assumption conservatively bounds fuel rod designs that incorporate annular and-or lower enrichment fuel pellets such as those used for axial blankets.

Each of the storage cell locations is modeled in KENO as a square cell with a pitch of 9.938 inches. The stainless steel canister, which controls the fuel assembly position within the array, is modeled with an inside dimension of 8.250 inches and is 0.093-inches thick (dimensions are taken from Table 2-2). The Boraflex poison absorbers are modeled inside the stainless steel canisters with a dimension of 8.00 inch in width by 0.100 inch in thickness. The sheathing panels are included as 0.021 inch in thickness. The active fuel, storage rack box and sheathing heights are modeled in KENO as 144 inches tall. The geometry of the Boraflex poison is represented as water in the KENO model, thus no credit is taken for the presence of the neutron absorbing, Boraflex material.

Reflective boundary conditions are applied to the X and Y surfaces of 2x2 cells, thus simulating an infinitely repeating array. A 2-foot water reflector is modeled above and below the storage cell geometry. The pool water is simulated to be full density (1 g/cm 3) at room temperature (68°F). The top and bottom surfaces of the water reflector have reflected boundary conditions.

3.1.1 KENO Model for the "All-Cell" Storage Configuration An "AMI-Cell" storage configuration' is modeled in KENO as a repeating 2x2 array of storage cells that contain depleted fuel assemblies as shown below.

Depleted Depleted Fuel Fuel Depleted Depleted Fuel Fuel Page 21 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 Note that the depleted fuel assemblies in the "All-Cell" storage configuration has been analyzed for the storage of fuel pins in the guide tubes. A KENO-produced plot of an "All-Cell" storage configuration is shown in Figure 3-1.

3.1.2 KENO Model for the "1-out-of-4 5.0 w/o Fresh with no IFBA" Storage Configuration The "l-out-of-4 5.0 w/o Fresh with no IFBA" storage configuration is modeled in KENO as a repeating 2x2 array with a fresh 5.0 w/o 235U fuel assembly occupying a storage cell location and depleted fuel assemblies occupying the remaining locations.

5.0 w/o Fresh Fuel Depleted Fuel Depleted Fuel Depleted Fuel A KENO-produced plot of a single "l-out-of-4 5.0 w/o Fresh with no IFBA" storage configuration is shown in Figure 3-2.

3.1.3 KENO Model for the "1-out-of-4 4.0 w/o Fresh with IFBA" Storage Configuration The "l-out-of-4 4.0 w/o Fresh with IFBA" storage configuration is modeled in KENO as a repeating 2x2 array with a fresh 4.0 w/o 231U fuel assembly occupying a storage cell location and depleted fuel assemblies occupying the remaining locations. Note that the fresh fuel assembly with enrichments greater than 4.0 w/o contains IFBA rods.

4.0 w/o Fresh Fuel Depleted Fuel Depleted Fuel Depleted Fuel A KENO-produced plot of a single "l-out-of-4 4.0 w/o Fresh with IFBA" storage configuration is shown in Figure 3-3. IFBA rods were modeled for this configuration using the layouts from Figure 3-5. [

]aC Page 22 of 116

I Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 3.1.4 KENO Model for Entire Spent Fuel Pool The Point Beach spent fuel pool (for this analysis only the north pool has been considered) is modeled in KENO as a rectangular water cell that is 408.00 inches long and 220.00 inches wide.

Seven rack modules, each with 90 to 110 cell locations, along with an empty cask area surrounded by concrete walls compromise the pool model. The floor and walls of the spent fuel pool are modeled by surrounding the rectangular water cell with two feet of concrete on the bottom and sides (followed by reflective boundary conditions). The pool dimensions are shown in Table 2-1. The pool water was modeled at room temperature conditions, 68°F, and full density (1.0 g/cm 3) with a neutronically-infinite two foot water reflector above the storage racks (followed by reflective boundary conditions). Figure 3-6 shows a KENO-produced plot of the spent fuel pool.

3.1.5 KENO Model for the Failed Fuel Rod Storage Basket As mentioned in Section'2.4, the design dimensions for the Failed Fuel Rod Storage Basket (FFRSB) are not available. Therefore, a conservative and bounding approach is used for modeling the FFRSB. No credit is taken for any stainless steel structural material (tubes, grids, plates, etc) for the basket. Fresh 5.0 w/o 235U fuel pins are placed in a uniform 7x7 array for simulation. This array is inserted in the "All-Cell" storage configuration by replacing one of the assemblies in that configuration. Figure 3-7 shows an FFRSB in the "All-Cell" configuration.

Periodic boundary conditions are applied to the X and Y surfaces of the 2x2 array, thus simulating an infinitely repeating array. A 2-foot water reflector is modeled above and below the storage cell geometry. The pool water is simulated to be full density (1 g/cm 3) at room temperature (68'F). The top and bottom surfaces of the water reflector have reflected boundary conditions.

The fuel rods in FFRSB are modeled by KENO as the Westinghouse 14x14 OFA design with no burnable absorber. The U0 2 density is 97.5% of theoretical density for the fresh fuel at 5.0 w/o 235U enrichment. Note that the fuel pellets in the fuel rods are modeled as a solid cylinder that is 144 inches tall. This assumption conservatively bounds fuel rod designs that incorporate annular and or lower enrichment fuel pellets such as those used for axial blankets.

3.2 Design Basis Fuel Assembly Figure 3-8 shows the Westinghouse 14x14 fuel assembly with the Standard, OFA and 422V+

assembly parameters given in Table 3-1. The Westinghouse standard fuel assembly design was modeled as the design basis fuel assembly to represent typical fresh and depleted fuel assemblies residing in all of the fuel assembly storage configurations. The checkerboard storage configurations utilize the OFA fuel design as the design basis, as this combination of fuel designs produces the highest reactivity. Furthermore, all postulated accident calculations use a fresh 5.0 w/o 235U fuel assembly to produce the largest reactivity increase.

The design basis fuel assemblies are modeled with the maximum enrichment over the active fuel length. The fresh fuel stack in a fuel rod is modeled as a solid right cylinder with a U0 2 density equal to 10.686 g/cm 3 (97.5 % of theoretical density). The depleted fuel ?ellets in a fuel rod are modeled as solid right cylinders with a U0 2 density equal to 10.412 g/cm (95.0 % of theoretical density). U0 2 density considerations are discussed in more detail in Section 3.4. In addition, Page 23 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 pellet dishing and chamfering, and natural or reduced enrichment pellets (even in blanketed assemblies), are not modeled in this analysis. Due to the increased fissile mass used in the calculations, this assumption results in conservative calculations of reactivity for all fuel assemblies stored in the racks.

No credit is taken for any spacer grids or sleeves. Since the physical fuel assemblies stored in the Point Beach Units I and 2 spent fuel pool have grids to maintain the appropriate spacing of fuel pins, their effect on reactivity must be considered. As they are not modeled in the analysis' calculations, calculations are performed to demonstrate that their reactivity is conservatively represented.

As fuel assembly reactivity response will vary with neutron spectrum effects due to depletion, proper quantification of these reactivity effects requires. the consideration of fuel ranging from low enrichment and zero burnup to 5.0 w/o 235U and high burnup values. As such, this analysis utilizes unirradiated 2.13 w/o 235U fuel and 5.0 w/o 235U fuel at 35,000 MWd/MTU to ensure that the ranges of enrichment/bumup combinations allowable for storage are bounded. Each fuel representation described above is simulated, with and without grids present, in the "All-Cell" storage configuration model.

The grids are modeled with the least absorptive grid material in use, Zircaloy, smeared with water across a cuboid the approximate size of physical grids. The number of Zircaloy atoms from an explicit representation of a grid is conserved in the smeared representation. Eight grids are modeled in this manner, with equidistant spacing of 18.0 inches across the height of the active fuel length.

The reactivity effects from the presence of grids are determined with the models described above at soluble boron concentrations ranging from 0 to 800 ppm in increments of 100 ppm. These calculations utilize SCALE5.1 to investigate the reactivity effects from grids. As only reactivity differences are determined, and absolute reactivity is not of interest, an extensive validation analysis is not presented. The results of these calculations are shown in Figure 3-4. Neglecting grids in this analysis is shown to be conservative at all bumup values.

Figure 3-5 shows the IFBA patterns for [

],b, c FBA rods in the Westinghouse 14x14 OFA fuel design used in this analysis. [

JaC 3.3 Modeling of Axial Burnup Distributions A key aspect of the bumup credit methodology used in this analysis is the inclusion of an axial burnup profile correlated with feed enrichment and discharge bumup of the depleted fuel assemblies. This effect is important in the analysis of the spent fuel pool characteristics since many of the spent fuel assemblies stored in the pool have a discharge burnup well beyond the Page 24 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 limit for which the assumption of a uniform axial burnup shape is conservative. Therefore, it is necessary to consider the burnt fuel assembly with a representative axial burnup profile.

]a, c Input to this analysis' distributed burnup profile is based on an evaluation of limiting axial burnup profile data provided in Reference 1. [

ac Page 25 of 116

I I

Westinghouse Non-Proprietary Class 3 1

WCAP-16541-NP, Rev. 2 1 To ensure that all discharged fuel assemblies are conservatively represented in the Point Beach Units 1 and 2 spent fuel pool, assemblies with uniform axial burnup profiles are also considered.

As shown in Figure 56 of Reference 18, the typical (or, "group-averaged") end-effect is negative at lower burnup values, so the use of a uniform burnup profile is conservative for lower burnups.

In this analysis, each determination of reactivity in the spent fuel pool environment is performed for a uniform and distributed burnup profile - the most reactive representation is then utilized to determine the minimum acceptable burnup requirement for safe storage.

The PHOENIX-P code was used to generate the isotopic concentrations for each segment of the axial burnup profile. Table 3-2 lists the moderator temperatures used in the spectral calculations for each node of the [

]ac axial burnup models and for a uniform burnup representation.

The core operating conditions considered in all depletion calculations are representative of uprated Point Beach Units 1 & 2. The absolute power level (1806 MWt) and moderator temperatures are specific to uprated Point Beach reactor cores (during extended power uprate conditions). Eight-zone moderator temperatures are determined assuming an axially linear temperature in the core that is interpolated between core TIN = 542.9 and core TOuT = 615.3 °F.

The fuel temperatures for each axial zone are calculated based on a representative fuel temperature correlation within the PHOENIX-P code.

The use of uprated core conditions leads to conservative determinations of reactivity (relative to the preuprate condition). This is due to the increased production of Pu nuclides from the slightly hardened neutron spectrum that results from increased power and temperature values. Therefore, the assembly representations are more reactive at any given point in their depletions. The values of assembly average burnups versus feed enrichment for which depleted fuel assemblies were simulated are presented in Table 3-3.

[.

]*'C The k1 and the isotopic number densities were then extracted for the KENO model development at these assembly conditions.

3.4 Tolerance / Uncertainty Calculations Using the input described above, analytical models were developed to perform the quantitative evaluations necessary to demonstrate that the effective multiplication factor for the spent fuel pool is less than 0.995 with zero soluble boron present in the pool water. Applicable biases factored into this evaluation are: 1) the methodology bias deduced from the validation analyses of pertinent critical experiments, and 2) any reactivity bias, relative to the reference analysis Page 26 of 116

[1111 Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 conditions, associated with operation of the spent fuel pool over a temperature range of 50'F to 1801F. Note that cases for nominal conditions were run with a full moderator density (1.0 g/cm 3), which actually corresponds to 400F, which is less than the normal operating range and conservatively captures perturbation effects resulting from moderation changes. The temperature bias is then determined through calculating the Aklff resulting from increasing the temperature to the upper end of the temperature range. Since moderator temperature/density effects are heavily dependent on the neutron spectrum considered, these calculations utilize depleted fuel at an enrichment/burnup combination that is least sensitive to moderator effects. The temperature bias is determined through explicit simulation with fuel at each enrichment and burnup combination above and below the required burnup - the largest determined value is reported. This is performed at 3.0, 4.0 and 5.0 w/o 235U for each storage configuration to ensure that the largest relevant temperature bias is considered.

A second allowance is based on a 95/95 confidence level assessment of tolerances and uncertainties. The following are included in the summation of variances:

a. The 95/95 confidence level methods variance

b. The 95/95 confidence level calculational uncertainty

c. Fuel rod manufacturing tolerances

d. Storage rack fabrication tolerances

e. Tolerance due to positioning the fuel assembly in the storage cell

f. Burnup and IFBA manufacturing uncertainty Items a. and b. are based on the calculational methods validation analyses described in subsection 1.4.2.

For item c., the fuel rod manufacturing tolerance for the reference design fuel assembly is assumed to consist of an increase in fuel enrichment of

]". This uncertainty bounds uncertainties in the manufacturing process, and for the "All-Cell" storage configuration, is applied through consideration of the reactivity effect resulting from a [

Iac change in enrichment at the fresh fuel allowable enrichment. This treatment is conservative since it over predicts the effect for higher enrichments. For the other storage configurations, the high reactivity fuel assembly drives the overall reactivity of the configuration, so the enrichment tolerance is determined by increasing the high enrichment assembly by J". These treatments allow nominal enrichment lff values to be used.in the bumup vs. enrichment polynomials. The nominal U0 2 density of manufactured fuel ranges from

]ax for various fuel designs, and the density tolerance is accounted for by performing all simulations at 97.5% of theoretical density (the highest credible density for PWR fuel). The fuel pellet outer diameter tolerance is [

I",C inches, and is considered in all storage configurations at the fresh fuel allowable enrichment. The fuel rod cladding thickness and outer diameter are considered in combination. The cladding thickness is decreased to its minimum tolerance of I

I"ac inches, and the cladding outer diameter is varied to its tolerance of I '2,c inches. Lastly, it is noted that actual fuel pellets are dished/chamfered and not right solid cylinders (as modeled in the calculations). Actual dished/chamfered fresh fuel pellets contain a reduction in fissile mass that is not represented here, providing additional margin in this analysis.

Page 27 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP' Rev. 2 For item d., the following uncertainty components were evaluated as outlined in Reference 5.

The inner stainless steel canister ID was increased from 8.250 inches to 8.333 inches and the thickness of the canister was decreased from 0.093 inches to 0.090 inches. The storage cell pitch was decreased from 9.938 inches to 9.928 inches. All tolerance perturbations were applied in the direction that increases reactivity relative to the nominal condition. If the tolerance perturbation results in a decrease in reactivity relative to the nominal condition, the reactivity effect for that tolerance is ignored.

In the case of the tolerance due to positioning of the fuel assembly in the storage cells (item e.),

all nominal calculations were carried out with fuel assemblies conservatively centered in the storage cells. Cases were run to investigate the effect of off-center position of the fuel assemblies for each of the fuel assembly storage configurations. These cases positioned the assemblies as close as possible in four adjacent storage cells.

For item f., [

a, C Table 3-4 through Table 3-6 provide a summary of the KENO results used in the calculation of biases and uncertainties for the fuel assembly storage configurations. Each Akff determined for physical tolerance calculations considers the UKENO values in a conservative fashion according to the following equation:

/Jkeff = (wic 0 +Oaw)

(knom. -

nom).d All biases are algebraically summed, and all uncertainty/tolerance values are statistically summed (i.e., root sum square). This can be demonstrated through the following equation:

M2

+

,eranceuncenanties 3.5 No-Soluble Boron 95/95 krf Calculational Results The following subsections present the KENO-calculated multiplication factors for the Point Beach spent fuel pool storage configurations.

The KENO calculations reported in this section were performed at 68°F, with maximum water density of 1.0 g/cm 3, to maximize the array reactivity, and with an axially distributed burnup Page 28 of 116

I Westinghouse Non-Proprietary Class 3 1

WCAP-16541-NP, Rev. 2 profile. The relative axial burnup profile used for these calculations is discussed in Section 3.3.

The resulting kfr data were then used to determine the burnup versus initial enrichment limits for a target keff value at zero soluble boron. The target value of keff was selected to be less than 0.995 by an amount sufficient to cover the magnitude of the analytical biases and uncertainties in these analyses.

The fuel assemblies modeled in these analyses are the Westinghouse 14x14 Standard/422V+ and OFA fuel assembly designs.

3.5.1 "All-Cell" Storage Configuration As described in subsection 3.1.1, the "All-Cell" storage configuration consists of a repeating 2x2 array of storage cells that contain depleted fuel assemblies.

The k.ff values were calculated for an infinite array of "All-Cell" storage configurations over a range of initial enrichment values up to 5.0 w/o 235U and assembly average burnups up to 35,000 MWD/MTU. From Table 3-4, the sum of the biases and uncertainties is 0.02813 Akeff units. Therefore, the target kefT value for the "All-Cell" storage configuration is 0.96687 (0.995-0.02813).

Table 3-7 lists the kff values for the "All-Cell" storage configuration versus initial enrichment and average bumups. The first entry in Table 3-7 lists the initial enrichment for no burnup. Based on the target keff value, the fresh enrichment for no burnup is 2.13 w/o 235U. The derived burnup limits, for enrichments greater than 2.13 w/o 235U, are based on the ken, values for 3.0, 4.0, and 5.0 w/o 235U. For each of these three enrichments, KENO calculations were performed at three assembly average burnup values with an axially distributed and uniform burnup profile. A second degree fit of the burnup versus limiting kYff data was then used to determine the burnup required to meet the target keff value of 0.96687.

The resulting bumup versus initial enrichment storage limits for 0, 5, 10, 15, and 20 years of decay time are provided in Table 3-8. The limiting burnups as a function of initial enrichment were fitted to a third degree polynomial for each of the decay periods. The resulting polynomial coefficients are rounded in a conservative manner such that the required burnup is greater than that required to meet the target ker. This adds additional conservatism to the curves. These polynomials are given below Table 3-8 and will be used to determine the burnup as a function of initial enrichment for the "All-Cell" storage configuration. The data contained in Table 3-8 and Table 4-1 are plotted in Figure 4-7.

3.5.1.1 Storage of Fuel Pins in the "All-Cell" Configuration Guide Tubes For storage of fuel pins in the guide tubes, the "All-Cell" storage configuration is considered.

Table 3-9 lists the k.ff values for the "All-Cell" storage configuration with increasing number of depleted fuel pins occupying the guide tubes. Due to moderator displacement, the resulting kfr values become less than the nominal keff value with increasing number of depleted fuel pins in the guide tubes. This decrease in reactivity shows that the "All-Cell" configuration with zero year decay time and no pins in the guide tubes is bounding for the fuel pins in the guide tubes.

Therefore, it is concluded that any fuel pin stored in the guide tubes of an assembly in the "All-Cell" configuration shall meet the burnup requirements of the "All-Cell" configuration with zero year decay time and without any fuel pins in the guide tubes.

Page 29 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 Fuel pins that do not meet the requirements of the "All-Cell" storage configuration may still be stored in the guide tubes if pins that exceed the burnup requirement are also loaded in the guide tubes to offset the excess reactivity. To illustrate this point, calculations have been performed for the "All-Cell" configuration with eight of the guide tubes loaded with burned fuel that is 10,000 MWD/MTU lower than the average burnup in the configuration and the remaining eight tubes are loaded with burned fuel that is 10,000 MWD/MTU higher. Table 3-10 shows that the keff results are very similar to the case with uniform burnup and smaller than the nominal "All-Cell" case. This analysis demonstrates that X number of fuel pins that do not meet the burnup requirement and have a maximum of Y MWD/MTU less than the required amount can be stored in the guide tubes only with an equal or greater number of fuel pins (X or greater) with burnups that exceed the burnup requirement by YMWD/MTU or higher.

3.5.2 "l-out-of-4 5.0 w/o Fresh with no IFBA" Storage Configuration As described in subsection 3.1.2, the "1-out-of-4 5.0 w/o Fresh with no IFBA" storage configuration consists of a repeating 2x2 array, with a fresh OFA fuel assembly at 5.0 w/o enrichment in a storage cell location and depleted Standard fuel assemblies in the remaining locations.

The kenf values were calculated for an infinite array of "l-out-of-4 5.0 Fresh with no IFBA" storage configurations over a range of initial enrichment values up to 5.0 w/o 235U and average burnups up to 55,000 MWD/MTU. From Table 3-5, the sum of the biases and uncertainties is 0.02104. Therefore, the target keff Value for the "1-out-of-4 5.0 Fresh with no JFBA" storage configuration is 0.97396 (0.995-0.02104).

Table 3-11 lists the ken' values for the "1-out-of-4 5.0 w/o Fresh with no IFBA" storage configuration versus initial enrichment and average burnups with an axially distributed and uniform burnup profile. The first entry in Table 3-11 lists the initial enrichment for no burnup.

Based on the target keff value, the interpolated enrichment for no burnup is 1.33 w/o 235U. The derived burnup limits, for enrichments greater than 1.33 w/o 235U, are based on the kefn values for 3.0, 4.0, and 5.0 w/o 235U. For each of these three enrichments, KENO calculations were performed at three assembly average burnup values for an axially distributed and uniform burnup profile. A second degree fit of the burnup versus limiting kefn data was then used to determine the burnup required to meet the target keff value of 0.97396. The resulting burnup versus initial enrichment storage limits for 0, 5, 10, 15, and 20 years of decay time are provided in Table 3-12.

The limiting burnups as a function of initial enrichment were fitted to a third degree polynomial.

The resulting polynomial coefficients are rounded in a conservative manner such that the required burnup is greater than that required to meet the target kefn.

This adds additional conservatism to the curves. These polynomials are given below Table 3-12 and will be used to determine the burnup as a function of initial enrichment for the "1-out-of-4 5.0 w/o Fresh with no IFBA" storage configuration. The data in Table 3-12 and Table 4-2 are plotted in Figure 4-8.

3.5.3 "1-out-of-4 4.0 w/o Fresh with IFBA" Storage Configuration As described in subsection 3.1.3, the "I-out-of-4 4.0 w/o Fresh with IFBA" storage configuration consists of a repeating 2x2 array, with a 4.0 w/o 235U Fresh OFA fuel assembly in a storage cell location and depleted Standard fuel assemblies in the remaining locations. For the "1-out-of-4 4.0 w/o Fresh with IFBA" storage configuration, burnup limits have been evaluated for the Page 30 of 116

I Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 depleted fuel assemblies and IFBA requirements have been determined for the fresh OFA fuel assembly with enrichments greater than 4.0 w/o 235U.

3.5.3.1 Burnup Requirements of the Depleted Fuel Assemblies The keff values were calculated for an infinite array of "1-out-of-4 4.0 w/o Fresh with IFBA" storage configurations over a range of initial enrichment values up to 5.0 w/o 235U and average burnups up to 55,000 MWD/MTU. From Table 3-6, the sum of the biases and uncertainties is 0.02327. Therefore, the target kff value for the "l-out-of-4 4.0 w/o Fresh with IFBA" storage configuration is 0.97173 (0.995-0.02327).

Table 3-13 lists the k-ff values for the "l-out-of-4 4.0 w/o Fresh with IFBA" storage configuration versus initial enrichment and average burnups with an axially distributed and uniform burnup profile. The first entry in Table 3-13 lists the initial enrichment for no burnup.

Based on the target leff value, the, interpolated enrichment for no burnup is 1.60 w/o 235U. The derived burnup limits, for enrichments greater than 1.60 w/o 235U, are based on the limiting keff values for 3.0, 4.0, and 5.0 w/o 235U. For each of these three enrichments, KENO calculations were performed at three assembly average burnup values for an axially distributed and uniform burnup profile. A second degree fit of the bumup versus keff data was then used to determine the burnup required to meet the target rff value of 0.97173. The resulting burnup versus initial enrichment storage limits for 0, 5, 10, 15, and 20 years of decay time are provided in Table 3-14.

The limiting burnups as a function of initial enrichment were fitted to a third degree polynomial.

The resulting polynomial coefficients are rounded in a conservative manner such that the required bumup is greater than that required to meet the target keff. This adds additional conservatism to the curves. These polynomials are given below Table 3-14 and will be used to determine the burnup as a function of initial enrichment for the "I-out-of-4 4.0 w/o Fresh with IFBA" storage configuration. The data in Table 3-14 and Table 4-3 are plotted in Figure 4-9.

3.5.3.2 IFBA Requirements for the Fresh Fuel Assembly Table 3-15 and Table 3-16 list the kff values versus the number of IWBA pins contained in the fresh fuel assembly with 4.5 w/o and 5.0 w/o 235U enrichments, respectively. For each fresh fuel enrichment and number of IFBA pins, keff was evaluated for different burnups of the depleted fuel assemblies with an initial enrichment of 5.0 w/o 235U. [

]a, C From these tables, fuel assembly burnup versus limiting rff data was fit to a second degree polynomial using the target ket" value of 0.97173. Note that this was the target~keff value used to determine the burnup requirements for the depleted fuel assemblies. The resulting polynomials were then used to determine the required number of IFBA pins needed to meet the fuel assembly burnup requirement of 41,361 MWD/MTU with 5.0 w/o initial enrichment. [

a C Table 3-17 contains the required number of IFBA pins versus initial enrichment for the fresh fuel assemblies with enrichments greater than 4.0 w/o. The required number of IFBA pins as a function of initial enrichment was fitted to a second degree polynomial. This polynomial is given below Table 3-17 and will be used to determine the number of IFBA pins as a function of initial Page 31 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 enrichment for the "1-out-of-4 4.0 w/o Fresh with IFBA" storage configuration. The data in Table 3-17 are plotted in Figure 4-10. [

a, 1 3.5.4 Interface Requirements Table 3-18 shows the entire spent fuel pool krff results for the interface configurations in the Point Beach storage racks. These interface configurations result in KENO-calculated multiplication factors that are less than the maximum of the infinite array multiplication factors for the involved storage configurations. As an example, the first analyzed interface involves the "1-out-of-4 5.0 w/o Fresh with no IFBA" configuration surrounded by the "All-Cell" storage configuration. From Table 3-7, the infinite array keff value for the "All-Cell" storage configuration is 0.96737 and from Table 3-11, the infinite array keff value for the "l-out-of-4 5.0 w/o Fresh with no IFBA" storage configuration is 0.97430. The maximum of these two values is 0.97430. From Table 3-18, the multiplication factor for the interface configuration was then compared to this maximum value to verify that the interface meets the storage requirements.

The KENO models constructed to analyze the interface effects follow the description of the entire spent fuel pool from subsection 3.1.4. The assembly loading requirements at the interface between different storage configurations are provided in Table 3-19. As seen from the results in Table 3-18 and Table 3-19, it is required that for storage configurations involving high and low reactivity assemblies (i.e., 1-out-of 4 configurations), the assemblies with lower reactivity must be placed at the interface. These interface requirements are depicted in Figure 4-4 to Figure 4-6.

Note that it is acceptable to leave a storage cell empty.

3.5.5 Burnup Requirements for Intermediate Decay Time Points For all the storage configurations in the Point Beach Spent Fuel pool crediting 241 P1

decay, burnup requirements for intermediate decay times should be determined using the smaller decay time curve (e.g. for a decay time of 7 years, the 5 year decay curve should be used.).

3.5.6 Failed Fuel Rod Storage Basket with 5.0 w/o 235U Fuel As described in subsection 3.1.5, FFRSB provides storage for a fixed 7x7 array of fuel rods.

Calculations were performed for different fuel rod pitch values in the basket to determine the most reactive and bounding case. The pitch values ranged from Pitch = O.D.fuel (fuel pins touching) to Pitch = 1.178 inches (fuel pins uniformly spaced over the entire storage cell, maximizing the moderator to fuel ratio). Table 3-20 lists the kefr values for the "All-Cell" storage configuration with one of the depleted fuel assemblies replaced with an FFRSB containing fresh 5.0 w/o 235U OFA fuel rods with increasing pitch values. The calculations were performed at 680F, with maximum water density of 1.0 g/cm3 to maximize the array reactivity.

As seen from Table 3-20, the resulting keff values were less than the nominal keff value of the "All-Cell" storage configuration even with the largest pitch value for the pins inside the basket.

Therefore, FFRSBs filled with fresh fuel rods with a maximum enrichment of 5.0 w/o 235U and no burnable absorbers can be stored in the "All-Cell" storage configuration.

Page 32 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 3.5.7 Empty Cells For all configurations at Point Beach, an empty cell is permitted in any location of the spent fuel pool to replace an assembly since the water cell will decouple the neutronic interaction between the spent fuel assemblies in the pool. Non-fissile material and debris canisters (containing non-fissile material) may be stored in empty cells of all storage, configurations.

3.5.8 Non-Fissile Equipment Non-fissile equipment, such as UT cleaning equipment, is permitted on top of the fuel storage racks, as such equipment will not increase reactivity in the spent fuel pool. This statement only relates to criticality safety concerns; thermal hydraulic or seismic considerations must be addressed separately.

3.5.9 Reconstituted Fuel Storage It is acceptable to store fuel meeting the storage requirements of any of the herein specified configurations, if that fuel has additionally been reduced in reactivity via reconstitution.

Modifications which without question would lower reactivity are the removal of fissile material (such as the removal of a fuel pin) and the subsequent replacement of fissile material with neutronically transparent or parasitic material.

3.6 Soluble Boron The total soluble boron requirement is defined here as the sum of three quantities:

SBCTOTAL S SBC95/95 + SBCR + SBCPA

where, SBCTOTAL is the total soluble boron credit requirement (ppm),

SBC951 95 is the soluble boron requirement for 95/95 kff less than or equal to 0.95 (ppm),

SBC R is the soluble boron required to account for bumup and reactivity uncertainties (ppm),

SBCPA is the soluble boron required to offset accident conditions (ppm).

Each of these terms is discussed in the following subsections.

3.6.1 Soluble Boron Requirement to Maintain kerr Less Than or Equal to 0.95 Table 3-21 contains the KENO-calculated kff values for the spent fuel pool from 0 to 1000 ppm of soluble boron, in increments of 200 ppm. These KENO models assume that the pool is filled with the "All-Cell" storage configuration containing depleted fuel at 55,000 MWDiMTU with 5.0 w/o 235U initial enrichment. The initial enrichment and burnup chosen to represent the storage configuration was based on minimizing the soluble boron worth. The soluble boron worth decreases as burnup increases, and this is included in the development of the polynomial fit. The reactivity worth, Akff, of the soluble boron was determined by subtracting the keff value, Page 33 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 for a given soluble boron concentration, from the kYfr value for zero soluble boron. The soluble boron concentration and reactivity worth data was then fitted to a second order polynomial, which is shown on the bottom of Table 3-21. This polynomial was then used to determine the amount of soluble boron required to reduce kefn by 0.05 Akff units, which is 269 ppm.

3.6.2 Soluble Boron Requirement for Burnup Reactivity Uncertainties The soluble boron credit, in units of ppm, required for reactivity uncertainties was determined by converting the uncertainty in fuel assembly reactivity and the uncertainty in absolute fuel bumup values to a soluble boron concentration, in units of ppm, necessary to compensate for these two uncertainties. The first term, uncertainty in fuel assembly reactivity, is calculated by employing a depletion reactivity uncertainty of 0.010 Akeff units per 30,000 MWD/MTU of burnup (based on internal proprietary design calculations) and multiplying by the maximum amount of bumup credited in a storage configuration. For this analysis, the maximum amount of burnup credited is 51,169 MWD/MTU for the "l-out-of-4 5.0 w/o Fresh with no IFBA" storage configuration.

Therefore, the depletion reactivity uncertainty is 0.01706 Akff.

The uncertainty in absolute fuel bumup values is conservatively calculated as 5% of the maximum fuel burnup credited in a storage configuration. This is identical in magnitude to the guidance of Reference 5, but the method of determining the reactivity worth is that described in Section 3.4. This method more realistically captures the reactivity behavior the storage configurations at the limiting bumup of interest. The maximum fuel burnup credited in the various storage configurations, the 5% uncertainty in these burnup values, and the corresponding reactivity values are given in Table 3-22.

The maximum reactivity change associated with a 5% change in burnup is 0.00781 Akeff units and occurs for the "All-Cell" storage configuration.

The total of the uncertainties in fuel assembly reactivity and burnup effects is 0.02487 Akeff. By applying the polynomial at the bottom of Table 3-21, the soluble boron concentration (ppm) necessary to compensate for this reactivity is found to be of 123 ppm.

3.6.3 Soluble Boron Required to Mitigate Accidents The soluble boron concentration, in units of ppm, to mitigate accidents is determined by first surveying all possible events that increase the keff value of the spent fuel pool. The accident event which produced the largest increase in spent fuel pool keff value is used to determine the required soluble boron concentration necessary to mitigate this and all less severe accident events. The list of accident cases considered includes:

" Dropped fresh fuel assembly on top of the storage racks,

• Misloaded fresh fuel assembly into an incorrect storage rack location, or outside the racks,

" Spent fuel pool temperature greater than 180'F.

Several fuel mishandling events were simulated using the KENO model to assess the possible increase in the keff value of the spent fuel pool. The fuel mishandling events all assumed that a fresh Westinghouse 14x14 OFA fuel assembly, enriched to 5.0 w/o 235U (and no burnable poisons), was misloaded into a storage rack or immediately adjacent to the racks (in proximity to Page 34 of 116

Westinghouse Non-Propietary Class 3 WCAP-16541-NP, Rev. 2 the cask laydown area). These cases were simulated with the KENO model [

a~c It is possible to drop a fresh fuel assembly on top of the spent fuel pool storage racks. In this case the physical separation between the fuel assemblies in the spent fuel pool storage racks and the assembly lying on top of the racks is sufficient to neutronically decouple the accident. In other words, dropping the fresh fuel assembly on top of the storage racks does not produce a positive reactivity increase. Note that the design of the spent fuel racks and fuel handling equipment is such that it precludes the insertion of a fuel assembly between the rack modules.

Calculations have shown that cool-down events produced less positive reactivity change compared to heat-up events. This is due to the fact that for cool-down events, only the temperature of the moderator is lowered since the moderator density is already at the maximum for nominal cases and the temperature effect alone is minimal or less compared to heat-up events. Therefore, results from heat-up events are reported here. All heat-up event calculations are performed with depleted fuel assemblies at 55,000 MVIWD/MTU in an attempt to further increase the reactivity effects from heat-up.

For the accident of a misloaded fresh fuel assembly, two scenarios were analyzed:

A depleted fuel assembly was replaced with a fresh fuel assembly in a storage configuration;

" A. fresh fuel assembly was placed in the cask area between the racks, face adjacent to either a depleted fuel or fresh fuel assembly of a storage configuration.

The above postulated accident scenarios involve the double contingency principle. This states that the analysis need not consider two unlikely, independent, concurrent events to ensure protection against a criticality accident. Thus, for these postulated accident conditions, the presence of soluble boron in the spent fuel pool can be assumed as a realistic initial condition, since not assuming its presence would be a second unlikely event.

The keff values for the accident scenarios described above are summarized in Table 3-23. Note that the nominal cases were developed by filling up the pool with one of the storage configurations and then the accident scenarios, as described above, were applied. This process was repeated for all the storage configurations. Note also that both the nominal cases and the accident scenarios were simulated with zero ppm boron in the pool to provide an overly conservative determination of the reactivity increase. As seen in Table 3-23, the accident event that produced the largest increase in the spent fuel pool keff value is the misloaded fresh 5.0 w/o 235U enrichment fuel assembly in an incorrect storage rack location of the "l-out-of-4 5.0 w/o Fresh with no IFBA" configuration. The required soluble boron concentration necessary to mitigate this and all less severe accident events was then calculated as 256 ppm using the Table 3-21 equation.

3.6.4 Total Soluble Boron Requirement Soluble boron in the spent fuel pool coolant is used in this criticality safety analysis to offset the reactivity allowances for calculational uncertainties in modeling, storage rack fabrication tolerances, fuel assembly design tolerances, and postulated accidents.

The magnitude of each soluble boron requirement is as follows:

Page 35 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 SBC95/ 95 = 269 ppm SBCp

= 123 ppm SBCPA

= 256 ppm SBCTToAL = 648 ppm Therefore, without considering an accident, the soluble boron (with 19.9%

o0B abundance) necessary to maintain ken" less than or equal to 0.95 (including all biases and uncertainties) is:

SBC95/ 95 + SBCRE = 269 ppm + 123 ppm = 392 ppm.

The soluble boron concentration required for a 1°B atom percent equal to 19.4 (expected to bound the lowest pool value crediting 10B depletion) is 402 ppm.

A total of 648 ppm of soluble boron (with 19.9% 10B abundance) is required to maintain klff less than or equal to 0.95 (including all biases and uncertainties) and assuming the most limiting single accident. The soluble boron concentration required for a 10B atom percent equal to 19.4 (expected lowest pool value crediting 'OB depletion) is 664 ppm. The recommended minimum boron level is 664 ppm and is sufficient to accommodate all the design requirements.

Page 36 of 116

Westinghouse NdnTProprietaryCass 3

{

WCAP-16541-NP, Rev. 2 Table 3-1 Fuel Assembly Data Used in Criticality Analysis of the Point Beach Spent Fuel Storage Racks 1-a,b,c Page 37 of 116

Westinghouse Non-Prprietary. Class 3 WCAP-165041-NP, Rev. 2 Table 3-2 Relative Power and Fuel/Moderator Temperatures for the Axially-Distributed 'Model a.bxc Page 38 of 116

Westinghouse Non-Propretary Class 3 WCAP-16541-NP, Rev. 2 Table 3-3 Burnup and Initial Enrichment Combinations Used to Determine the Isotopic Number Densities 3.0 w/o 235U 4.0 w/o 235U 5.0 w/o 23'U (MWD/MTU)

(MWD/MTU)

(MWD/MTU) 0 0

0 5,000 15,000 25,000 15,000 25,000 35,000 25,000 35,000 45,000 35,000 45,000 55,000 Page 39 of 116

Westinghouse Non-Proprietary ClassO 3

WCAP-16541-NP, Revm 2 Table 3-4

• ff Values for the Tolerance/Uncertainty Cases for the "All-Ce'll" Storage Configuration a.b~c.

a,b,c

[

I Page 40 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev 2&

Table 3-5

• km Values for the Tolerance/Uncertainty Cases for the"'1-out-of-4 5,.0 wl0 Fresh with no EFBA" Storage Configuration a~b~c

[E

ýa,bc Page 41 of 116

WestinighouseNon-Proprietary Class 3 WCAP-6541-NP, Rev. 2 Table 3-6 kdr Values for the To1erance/Uncertainty Cases for the 1-OUt-of-P4 4.0 w/o Fresh, with IFBA" Storage Configuration Page 42 of 116 a,bi,c L

I

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 Table 3-7 Limiting klff Values versus Initial Enrichment and Assembly Burnup for the "All-Cell" Storage Configuration (for 0 to 20 Years Decay)

Initial Burnup kff Value9 Enrichment (MWD/

(w/o 3U)

MTU) 0 year decay 5 years decay 10 years decay 15 years decay 20 years decay 2.13 0

0.96737 +/- 0.00034 0.96737 +/- 0.00034 0.96737 +/- 0.00034 0.96737 +/- 0.00034 0.96737 +/- 0.00034 3.0 5,000 1.00143 +/- 0.00034 1.00076 +/- 0.00032 1.00047 +/- 0.00033 0.99964 +/- 0.00036 0.99989 +/- 0.00036 3.0 15,000 0.91841 +/- 0.00035 0.91127 +/- 0.00031 0.90700 +/- 0.00030 0.90234 +/-0.00029 0.89960 +/- 0.00029 3.0 25,000 0.84813 +/- 0.00035 0.83896 +/- 0.00033 0.83053 +/- 0.00033 0.82527 +/- 0.00033 0.82115 +/- 0.00034 4.0 5,000 1.06797 +/- 0.00036 1.06821 +/- 0.00034 1.06720 +/- 0.00036 1.06608 +/- 0.00035 1.06651 +/- 0.00036 4.0 15,000 0.99148 +/- 0.00032 0.98681 +/- 0.00033 0.98361 +/- 0.00035 0.98105 +/- 0.00033 0.97925 +/- 0.00032 4.0 25,000 0.92199 +/- 0.00030, 0.91255 +/- 0.00032 0.90712 +/- 0.00033 0.90307 +/- 0.00035 0.89943 +/- 0.00038 5.0 15,000 1.04403 +/- 0.00034 1.04115 +/- 0.00036 1.03887 +/- 0.00036 1.03700 +/- 0.00031 1.03568 +/- 0.00036 5.0 25,000 0.98000 +/- 0.00032 0.97207 +/- 0.00035 0.96622 +/- 0.00030 0.96238 +/- 0.00031 0.95826 +/- 0.00029 5.0 35,000 0.92535 +/- 0.00034 0.91685 +/- 0.00040 0.91108 +/- 0.00034 0.90573 +/- 0.00039 0.90139 +/- 0.00032 9 These results (and those in subsequent tables) illustrate the standard deviation from the monte carlo simulations. However, it should be noted that methodology and calculational uncertainties such as this are considered in the determination of biases and uncertainties. Since the uncertainty has been incorporated into developing the target kIf for each storage configuration, it is appropriate to utilize nominal k~ff values when developing the bumup vs. enrichment curves.

Page 43 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 Table 3-8 Fuel Assembly Burnup versus Initial Enrichment for the "All-Cell" Storage Configuration Initial Limiting Burnup (MWD/MTU)

Enrichment (w/o 235U) 0 yr decay 5 yr decay 10 yr decay 15 yr decay 20 yr decay 2.13 0

0 0

0 0

3.0 8935 8493 8330 8051 7966 4.0 18475 17650 17172 16789 16554 5.0 27349 25965 25006 24355 23800 Note that the assembly burnups as a function of initial enrichment for each decay period are described by the following polynomials:

Assembly Bumup (0 yr decay) = 20 e3 - 573 e2 + 12811 e - 24881 Assembly Bumup (5 yr decay) = -34 e3 - 13 e2 + 10506 e - 21990 Assembly Bumup (10 yr decay) = -39 e3 - 36 e2 + 10537 e - 21904 Assembly Bumup (15 yr decay) = -108 e3 + 710 e2 + 7764 e - 18715 Assembly Bumup (20 yr decay) = -128 e3 + 865 e2 + 7269 e - 18170 Page 44 of 116

Westinghouse Non-Proprietary Class 3 1WCAP-16541-NP, Rev. 2 Table 3-9 Limiting keff Values for the "All-Cell" Storage Configuration with Fuel Pins in the Guide Tubes Initial Burnup kff Value Enrichment (MWD/

(w/o 21,U)

MTU) 0 pins in the tubes 4 pins in the tubes 9 pins in the tubes 16 pins in the tubes 3.0 5,000 1.00143 +/- 0.00034 0.99962 + 0.00034 0.99525 + 0.00036 0.98815 + 0.00036 3.0 15,000 0.91841 +/- 0.00035 0.91700 + 0.00031 0.91198 + 0.00031 0.90623 + 0.00032 3.0 25,000 0.84813 +/- 0.00035 0.84732 + 0.00034 0.84274 + 0.00031 0.83706 + 0.00031 4.0 5,000 1.06797 +/- 0.00036 1.06559 + 0.00036 1.05956 + 0.00033 1.05200 + 0.00034 4.0 15,000 0.99148 +/- 0.00032 0.98948 + 0.00031 0.98336 + 0.00036 0.97639 + 0.00034 4.0 25,000 0.92199 +/- 0.00030 0.91973 + 0.00031 0.91461 + 0.00030 0.90796 + 0.00031 5.0 15,000 1.04403 +/- 0.00034 1.04117 + 0.00038 1.03513 + 0.00033 1.02766 + 0.00034 5.0 25,000 0.98000 +/- 0.00032 0.97769 + 0.00033 0.97173 + 0.00034 0.96477 + 0.00037 5.0 35,000 0.92535 +/- 0.00034 0.92274 + 0.00034 0.91825 + 0.00037 0.90993 + 0.00033 Page 45 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 Table 3-10 Limiting keff Values for the "All-Cell" Storage Configuration with Fuel Pins in the Guide Tubes: Effect of Split Burnup Initial Burnup kff Value Enrichment (MWD/

(w/o 3 MTU) 0 pins the tubes 16 pins with 16 pins with split MT) pn te ubs uniform burnup burnupl0 3.0 15,000 0.91841 +/- 0.00035 0.90623 + 0.00032 0.89926 +/- 0.00034 3.0 25,000 0.84813 +/- 0.00035 0.83706 + 0.00031 0.83783 +/- 0.00035 4.0 15,000 0.99148 +/- 0.00032 0.97639 + 0.00034 0.96889 +/- 0.00036 4.0 25,000 0.92199 +/- 0.00030 0.90796 + 0.00031 0.90660 +/- 0.00037 5.0 25,000 0.98000 +/- 0.00032 0.96477 + 0.00037 0.96000 +/- 0.00032 5.0 35,000 0.92535 +/- 0.00034 0.90993 + 0.00033 0.91026 +/- 0.00036 10 Eight of the pins have 10,000 MWD/MTU higher burnup than the average and eight have 10,000 MWD/MTU lower.

Page 46 of 116

Westinghouse Non-Proprietary Class 3 1

WCAP-16541-NP, Rev. 2 1 I

Table 3-11 Limiting keff Values versus Initial Enrichment and Assembly Burnup for the "l-out-of-4 5.0 w/o Fresh with no IFBA" Storage Configuration (for 0 to 20 Years Decay)

Initial Burnup kIE Value Enrichment (MWD/

(w/o 13)

MTU) 0 year decay 5 years decay 10 years decay 15 years decay 20 years decay 1.33 0

0.97430 +/- 0.00038 0.97430 +/- 0.00038 0.97430 +/- 0.00038 0.97430 +/- 0.00038 0.97430 +/- 0.00038 3.0 15,000 1.01231 + 0.00040 1.00940 + 0.00036 1.00725 + 0.00040 1.00561 + 0.00038 1.00307 + 0.00042-3.0 25,000 0.98168 + 0.00043 0.97612 + 0.00043 0.97260 + 0.00049 0.96980 + 0.00046 0.96717 + 0.00040 3.0 35,000 0.95914 + 0.00047 0.95323 + 0.00043 0.94853 + 0.00047 0.94512 + 0.00045 0.94305 + 0.00049 4.0 25,000 1.01478 + 0.00037 1.00932 + 0.00039 1.00568 + 0.00038 1.00335 + 0.00039 1.00113 + 0.00041 4.0 35,000 0.98619 + 0.00042 0.97989 + 0.00048 0.97510 + 0.00041 0.97203 + 0.00040 0.96896 + 0.00043 4.0 45,000 0.96389 + 0.00043 0.95684 + 0.00044 0.95270 + 0.00043 0.94959 + 0.00043 0.94686 + 0.00048 5.0 35,000 1.01320 + 0.00039 1.00729 + 0.00041 1.00250 + 0.00042 0.99944 + 0.00044 0.99716 + 0.00040 5.0 45,000 0.98724 + 0.00042 0.98063 + 0.00042 0.97528 + 0.00047 0.97209 + 0.00046 0.96936 + 0.00045 5.0 55,000 0.96609 + 0.00042 0.95912 + 0.00041 0.95467 + 0.00041 0.95135 + 0.00041 0.94798 + 0.00045 Page 47 of 116

I Westinghouse Non-Proprietary Class 3 1 WCAP-16541-NP, Rev. 2 1 Table 3-12 Fuel Assembly Burnup versus Initial Enrichment for the "1-out-of-4 5.0 w/o Fresh with no IFBA" Storage Configuration Initial Limiting Burnup (MWD/MTU)

Enrichment (w/o 235U) 0 yr decay 5 yr decay 10 yr decay 15 yr decay 20 yr decay 1.33 0

0 0

0 0

3.0 28193 25861 24513 23592 22681 4.0 40291 37453 35461 34316 33140 5.0 51169 48037 45589 44326 43205 Note that the assembly burnups as a function of initial enrichment for each decay period are described by the following polynomials:

Assembly Burnup (0 yr decay) = 322 e3 - 4474 e2 + 31502 e - 34741 Assembly Burnup (5 yr decay) = 260 e3 -3624 e2 + 27340 e - 30563 Assembly Burnup (10 yr decay) = 269 e3 - 3638 e2 + 26461 e - 29391 Assembly Burnup (15 yr decay) = 250 e3 - 3357 e2 + 24973 e - 27864 Assembly Bumup (20 yr decay) = 265 e3 - 3377 e2 + 24293 e - 26960 Page 48 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 Table 3-13 Limiting kff Values versus Initial Enrichment and Assembly Burnup for the "l-out-of-4 4.0 w/o Fresh with IFBA" Storage Configuration (for 0 to 20 Years Decay)

Initial Burnup kfr Value Enrichment (MWD/

(w/o 23U)

MTU) 0 year decay 5 years decay 10 years decay 15 years decay 20 years decay 1.60 0

0.97239 +/- 0.00037 0.97239 +/- 0.00037 0.97239 +/- 0.00037 0.97239 +/- 0.00037 0.97239 +/- 0.00037 3.0 15,000 0.98974 + 0.00035 0.98701 + 0.00040 0.98392 + 0.00038 0.98224 + 0.00042 0.98064 + 0.00036 3.0.

25,000 0.95585 + 0.00037 0.95042 + 0.00042 0.94564 + 0.00041 0.94163 + 0.00043 0.94059 + 0.00044 3.0 35,000 0.93016 + 0.00039 0.92413 + 0.00044 0.91947 + 0.00045 0.91610 + 0.00041 0.91295 + 0.00047 4.0 25,000 0.99219 + 0.00038 0.98679 + 0.00040 0.98316 + 0.00036 0.97958 + 0.00040 0.97711 + 0.00041 4.0 35,000 0.96111 + 0.00040 0.95288 + 0.00037 0.94874 + 0.00039 0.94403 + 0.00040 0.94205 + 0.00045 4.0 45,000 0.93598 + 0.00044 0.92881 + 0.00046 0.92364 + 0.00044 0.91969 + 0.00041 0.91599 + 0.00041 5.0 35,000 0.99121 + 0.00039 0.98436 + 0.00037 0.97997 + 0.00041 0.97592 + 0.00037 0.97248 + 0.00040 5.0 45,000 0.96180 + 0.00040 0.95489 + 0.00042 0.94979 + 0.00040 0.94583 + 0.00038 0.94216 + 0.00042 5.0 55,000 0.93909 + 0.00044 0.93127 + 0.00041 0.92517 + 0.00038 0.92191 + 0.00041 0.91862 + 0.00045 Page 49 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 Table 3-14 Fuel Assembly Burnup versus Initial Enrichment for the "1-out-of-4 4.0 w/o Fresh with IFBA" Storage Configuration Initial Limiting Burnup (MWD/MTU)

Enrichment (w/o 235U) 0 yr decay 5 yr decay 10 yr decay 15 yr decay 20 yr decay 1.60 0

0 0

0 0

3.0 19883 18644 17595 16901 16783 4.0 31343 28908 27862 26759 26321 5.0 41361 39062 37517 36261 35293 Note that the assembly burnups as a function of initial described by the following polynomials:

enrichment for each decay period are Assembly Burnup (0 yr decay) = 124 e3 - 2209 e2 + 22335 e - 30589 Assembly Bumup (5 yr decay) = 358 e3 - 4351 e2 + 27475 e - 34288 Assembly Bumup (10 yr decay) = 192 e3 - 2610 e2 + 21433 e - 28398 Assembly Burnup (15 yr decay) = 219 e3 - 2806 e2 + 21397 e - 27949 Assembly Burnup (20 yr decay) = 217 e3 - 2887 e2 + 21718 e - 28247 Page 50 of 116

]Westinghouse Non-Proprietar Class 3 WCAP-1654i-NP, Rev. 2 Table 3-15 Limiting kifValues versus Number of IFBA Pins (1.OX) Contained in. the 4.5 w/o 23SU Fresh Fuel: of t-he "1-out-of-4 4.0 w/o Fresh itfh WOBA" Storage Configuration Enrichment of Burnup of Number of IFBA Pins, Fresh Fuel Depleted Fuel in Fresh Fuel kr (w/o I SU)

(MWD]MTU) a.c 4.5

35,000 I.00259 + 0.00041 4.5 45,000 0.97478 +-0.00045 4.5

ý55,000 0.95407 + 0.00644 4.5*

3.;00 019,9.199 + 0;00037 4.5 35,000 4.5 451,000 0_96399

_+

0.0,0038 4.5 55,000

_0194036:

+

_00043 4*5 305000 0.98141 + 0.00035 4.5 45;000 0.95302 + 0.00041 4.5

=55,000 0.93137 + 0.00043 4.5 35,000 0.97331 + 0.00039 4.5 45:000 0.94826 + 0.00039 4.5 1

55,000 0.9267 1 + 0.00039 Page 5.1. of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 Table 3-16i Limiting kff Values versus Number, of IFBA Pins (1.0X)Contained -in the 5.0 w/o 235U

'Fresh Fuel.of the ".1-outof-4 4.0 w/o Fresh with IFBA",Storage Configuration Enrichment of the Burnup of'the Number of Fresh Fuel Depleted Fuel IFBA Pins ker (wio 25U)

(MWDIMTU) a~c 5.0 35,000.

1.01320 + 0.00039 5.0 45,000 0.98724 + 0.00042 5.0

55,000 0:96609 + 0.00042 5.0 35,000 1, 00281 +/- 0.00039 5.10 45,000 0.97570 + 0.00044 5.0 55,000 0:95366 +ý 0,00044 50 35,000 0.99188 + 0.00035 5.0 45,000 0.96540 + 0.0ý0040 5.0 55,000 0.194393 + 0.00041 5.0 35M000 0.98350 + 0.00043 5.0 454000 0.95875: +,0.00039 5.0 55,000 0.93802 + 0.00048 Page 52. of 116

Westinghouse Non-Proprietary Class 3

[

WCAP-16541-NP, Rev. 2 [

Table 3-17 Number of IFBAs versus Initial Enrichment for the Fresh Fuel Assembly in the "1-out-of-4 4.0 w/o Fresh with IFBA" Storage Configuration Initial Enrichment Number of IFBAs (W/o 235U)

(1.OX) 4.0 0

4.5 19 5.0 39 Required Number of IFBA pins as a function of enrichment is given by the following polynomials:

Number of IFBA Pins = 2 e2 + 21 e - 116 Page 53 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 Table 3-19 Assembly Loading Requirements at the Interface between Different Storage Configurations Assembly that Must be Loaded at the Interface Configuration with Another Configuration" "All-Cell" Any "1-out-of-4 5.0 w/o Fresh with no IFBA" Only Depleted Fuel Assemblies "1-out-of-4 4.0 w/o Fresh with IFBA" Only Depleted Fuel Assemblies Instructions:

1. Identify which storage configurations will be interfaced.

2.

Look up the assembly loading requirements for both storage configurations.

"An empty storage location is always permitted.

Page 55 of 116

Westinghouse Non-Proprietary Class 3 WCAP-1 6541 -NP, Rev. 2 Table 3-20 kerr Values for the Failed Fuel Rod Storage Basket with 5.0 w/o 235U Fresh Fuel in the "All-Cell" Storage Configuration Fuel Pin Pitch in the FFRSB (inches) krff with FFRSB.

Nominal kfrr for "All-Cell" P = 0.400" (fuel pins touching) 0.90101 +/- 0.00039 0.96737 +/- 0.00034 P = 0.937" (typical storage basket design pitch) 0.93310 +/- 0.00034 0.96737 +/- 0.00034 P = 1.178" (maximum pitch in the cell) 0.94417 +/- 0.00036 0.96737 +/- 0.00034 Page 56 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 Table 3-21 klff Values as a Function of Soluble Boron Concentration for the Spent Fuel Pool with Depleted Fuel Assemblies in the "All-Cell" Storage Configuration Soluble Boron Concentration (ppm) kefn 0

0.83959 +/- 0.00023 200 0.80198 +/- 0.00021 400 0.76973 +/- 0.00021 600 0.74291 +/- 0.00022 800 0.71880 +/- 0.00019 1000 0.69724 +/- 0.00021 Note that the following polynomial describes an amount of soluble boron as a function of Akeff for the entire spent fuel pool:

ppm = 17596 Akeff2 - 4496 Akff Page 57 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 Table 3-22 Summary of Burnup Reactivity Uncertainties for the Storage Configurations Maximum 5% Burnup Burnup Uncertainty Configuration (MWD/MTU)

(pcm)

Akerr "All-Cell" 27349 1367 0.00781 1-out-of-4 5.0 w/o Fresh with no 51169 2558 0.00527 IFBA 1-out-of-4 4.0 w/o Fresh with 41361 2068 0.00589 IFBA I

I Page 58 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 Table 3-23 kfi Values for Various Accident Scenarios in the Spent Fuel Pool 1-out-of-4 4.0 w/o 1-out-of-4 5.0 w/o Fresh with IFBA Fresh with no IFBA Accident Scenarios kn Akff klff Aknff Akff 0.96307 +/-

0.96838 +

0.96992+/-

Nominal configuration 0.00021 0.00022 0.00024 Msloaded fresh fuel 0.99256 +/-

1.00757 +/-

1.01787 +

assembly into bumup 0.00029 0.02949

-0.00032 0.03919 0.00029 0.04795 storage rack location Msloaded fresh fuel 0.96419 +/-

0.97869 +

0.98676 +

assembly in the cask area 0.00024 0.00112 0.00033 0.01031 0.00042 0.01684 between storage racks Spent fuel pool temperature greater than 0.84488 +

0.0093612 0.92384+

-0.0045413 0.94273 +

-0.01222'4 normal operating range 0.00019 0.00022 0.00022 (240°F) 12 This Ak values is relative to the nominal all-cell storage configuration kfr of 0.83552 + 0.00020 with depleted fuel at 55,000 MWD/MTU.

13 This Ak values is relative to the nominal 1-out-of-4 5.0 w/o Fresh with no IFBA storage configuration klfe of 0.92838 +

0.00024 with depleted fuel at 55,000 MWD/MTU.

14 This Ak values is relative to the nominal 1-out-of-4 4.0 w/o Fresh with IFBA storage configuration kff of 0.95495 + 0.00026 with depleted fuel at 55,000 MWD/MTU.

Page 59 of 116

I I Westinghouse Non-Proprietary Class 3 1 WCAP-16541-NP, Rev. 2 This page intentionally left blank.

Page 60 of 116

~Page 61 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 This page intentionally left blank.

Page 62 of 116

Page 63of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 This page intentionally left blank.

Page 64 of 116

TNO Output Plot for the "L-out-(

Storage Configurati Page 65of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 This page intentionally left blank.

Page 66 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 1.70 1.50 1.30 1.10 0.90 0.70 250 200 150 Ak(ff (PC-)

100 50

-0 800 0

100 200 300 400 500 600 700 Soluble Boron Concentration (ppm)

Figure 3-4. Reactivity Comparison of Assemblies with Grids vs. Assemblies with no Grids in the Point Beach Spent Fuel Pool Model Page 67 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 This page intentionally left blank.

Page 68 of 116

"s4 iA"1 5A Westinghouse No'flProprietaiy Class 3 A 'i WCAP-16541-NP, Rev. 2 A"

.t,6cv 4444

'5 sA.t

'""c">>

"ii"'

4>44.

"4.

• 244"

""<4

'<ti-ti-

.5 A'2" '

' 54" "'45 A' ott' 4s,4

"'5"5254

'A bay" A

4t

-s, abc is' 4<

554452' 2" i-4' 4>4' tAp" 44>44 4<

r~ t"~4>tP>tJ

's"'""'44s' 4

455'"'.

524" 54444 54' 5' 4<

is" >~

4 As 4:"

4*4'~A

""Ar.

'2'>>

A"'>

5~¶ Aiss 5

'Si

~Ai-"A' 44>

2

~>

AKs~

"44.""""';~'-~

~

754is As

'A r"

4124. 4441>"'

's<

4" 5'

<44 4'

~

44

"'A.

isA'S A

At

• 4A14 4

~ŽŽ2, '52542

,""i4t

'4.

A~ ~

" 2 4 tAAŽ,A "'5" 44 UA"AA A 44424' Ss,442"<~A'A tAt

'Ž54 2">,

1. 4

~

544454Ž5 t%~'AtttS4tK it

"'ist>""A

'A'~5t tt~"4>t'> >

4'ŽAŽ'4%ws's 44 4 js~,4~""J4>

4" 4"

44

<4" t4tŽ"ss14'~s$l4sŽ

~444sŽ."'4' si"44,"

<'2 444

""As 54 14 14, i%44tnŽŽ4ts's t1 2 ~4ŽJt 2'

42">,

>44 2tc4tL

.S4ttt~4 414 41 7'J is>"

'At A'

<"'~

~<.

A

'S<5A'A

~ vt ~'ThWA$~

AS isis""

54Ž54 1<

'5<

2 ~'~A'>4 AA4244Ž<"5 4' s>4~

4~

1. 4Kt">As~

sA4542'44 As's,

'i-st's A

7' ~

1's/fr'

>5tt' 52441,

ŽA"Ž"'444~A5>"'ŽA4t' bits) sssss4'2' 5Ž542' ""A""'

4"Žr>4 44ps"'

A'~AŽ'A.544A44A~A'44 A'ŽAs2

"'1

~

444 45>4<44" I

$14'AThA "2'~

'A2A~A""'

Ž4Ž4<424' A~"'5

-i A" i'isi>

A""4'A\\

4.

444444" 4'

45 5"'

A" A""442A'4'"

44 AA4>'

A

>4<

~

444>4

.41.114

>44<'

"4 A".

Ž54 5.

44 29

'4" 414>44> '4'>

<<~b'4""'""

~.

>414" A

'52 44

>4'4>

"'/<-K"> 14 22' 4 At K

2 A,'2*"2~4

• 41Ž'

4 55'45"i"'

<44 4< 4At"44 is' IS~t##

'VA 4'> 3/4 "5"'"'

4ts ta'2

'45Ž 44' 2"' >"""

""525 5Ž4""

'44yA4s"'

'A's' "'v 44' At, At

• 415 A

'A'.'

1PA~

~

2

"Ž142"

'is>

~"

s,54

>4411'.

"'4 It it>

5Ž2".' 44Ž2" 4"' >t">'4<

<441. Li'" >49Ž

'5 >44%. ">5<

5.

(it>

ii tA4A5'A"~ 5

'5445

.4 "44'i'KA"> 4<

""'A""

4"4"'

-~

"As" 5Ž1>""

"As' s"

5

'"2""

4444>>

A 425<

4'"

it>

AS"

~5>4<

Ž4

"'A A4'A<"

A(454 Figure 3 5 IFBA Patterns Used in the Point Beach Criticality Analysis' 4444Ž1st 5A4A' '44' A AiD

JAŽt'j A"A"A"4'A45"'"AS"A 425452 '

'is A

54 4>

4's,'

54"'

"4 A'*A~AA's,Ž5.A ;~455 5' A A

4 A

K At

'4 5 55

~

554Ž 4

Page 69of 116~

'4

'5si's55'5's'i'A5~44'<

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 This page intentionally left blank.

Page 70 of 116

ughouse Non-Proprietary Clas~ 3 WfA

/

N N'~N KNN.

NN~K~N

~NN N

-~

N N N

-~

K~N

~

N NNNNNNNNNW~C UNNN~

~NN.'NNKN~NNN NNNNN~NN~N/~N>NNNN>NK K

~NNjN~

N~N NNNNNN N~N NN~NN NNN~

}~K' NNNN~N N NNNNNNNN N~NN NNNNNN~N~K'N~

N W~K'NNK*N4/NNK~

N NN N~>NN~~N

~KN>>~~

~

NNNNK' N N~

~N:;,~.N~N>1N:NN~NNNNNNKNNNNN N~~N

~ ~

N N

NKNNN>N NNN~j N~> >

N NNNNNNNNNNN.

~

NN>~NNNK~

7N N N

NNNNNNNNNNNNN N

NNNN>N NKNN~NNNNNN VNNNNN~NNNNN 9

SN~N NNNNNN N

N K'

7 utput Plot for the Spent Fuel Pool Loade

~V/o Fresh withiEBA" Storage Configiirai KPN NNNNN NNNK'N N~NNN NN~*NNNNNN~

• N.NN~N.

7 4

NK KNNN 4

N N

N N N

N

~ <N N

N

~Page71ofII6 N

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 This page intentionally left blank.

Page 72 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 This page intentionally left blank.

Page 74 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 This page intentionally left blank.

Page 76 of 116

Westinghouse Non-Proprietay Class 3 WCAP-1654!-NP,,Rev. 2 a,b,c Figure 3-9 Sketch of Axial.Zones Used in Fuel Assembly Page 77 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 This page intentionally left blank.

Page 78 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 This page intentionally left blank.

Page 80 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 This page intentionally left blank.

Page 82 of 116

Westinghouse Non-Proprietary Class 3 WCAPA16541-NP,,Rev4, 2.

a,c Figure 3-12 Reactivity Comparison of Bounding Axial Burnup Profile vs. the Burnup Profile in the Point Beach Spent Fuel Pool Model Page 83 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 This page intentionally left blank.

Page 84 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 4.0 Summary of Results The following sections contain the criticality analysis results for the Point Beach spent fuel pools

• with soluble boron credit.

4.1 Allowable Storage Configurations 4.1.1 "All-Cell" Storage Configuration Figure 4-1 displays the allowable storage configurations for the "All-Cell" storage. The "All-Cell" storage rack configuration will be employed to store depleted fuel assemblies which meet the requirements of Table 4-1 and Figure 4-7.

4.1.1.1 Storage of Fuel Pins in the Guide Tubes in an "All-Cell" Storage Configuration Fuel pins stored in the guide tubes of an assembly in an "All-Cell" configuration shall meet the burnup requirements of the "All-Cell" configuration with zero year decay time and without any fuel pins in the guide tubes. Fuel pins that do not meet the requirements of the "All-Cell" storage configuration (i.e., pins that have less burnup by a certain amount) can be stored in the guide tubes only if the same or greater number of pins that exceed the burnup requirement by the same or larger amount are also loaded in the guide tubes to offset the excess reactivity.

4.1.2 "1-out-of-4 5.0 w/o Fresh with no IFBA" Storage Configuration Figure 4-2 displays the allowable storage configurations for the "1-out-of-4 5.0 w/o Fresh with no IFBA" storage. The "1-out-of-4 5.0 w/o Fresh with no IFBA" storage configuration will be employed to store fresh assemblies with enrichments up to 5.0 w/o 235U and depleted fuel assemblies which meet the requirements of Table 4-2 and Figure 4-8.

4.1.3 "1-out-of-4 4.0 w/o Fresh with IFBA" Storage Configuration Figure 4-3 displays the allowable storage configurations for the "I-out-of-4 4.0 w/o Fresh with IFBA" storage. The "1-out-of-4 4.0 w/o Fresh with IFBA" storage configuration will be employed to store fresh fuel assemblies with enrichments up to 4.0 w/o 235U and depleted fuel assemblies which meet the requirements of Table 4-3 and Figure 4-9. The fresh fuel assemblies with enrichments greater than 4.0 w/o 235U and up to 5.0 w/o U shall meet the minimum IFBA requirements of Table 4-4 and Figure 4-10. [

a,b, c 4.1.4 Burnup Requirements for Intermediate Decay Time Points For all the storage configurations in the Point Beach Spent Fuel pool crediting 24 pu decay, burnup requirements for intermediate decay times should be determined using the smaller decay time curve (e.g. for a decay time of 7 years, the 5 year decay curve should be used.).

Page 85 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 4.2 Interface Requirements in Spent Fuel Pool Storage Racks Fuel storage patterns used at the interface of storage configurations shall comply with the assembly loading requirements provided in Table 4-5 and Figure 4-4 to Figure 4-6. Note that it is acceptable to leave a storage cell empty.

4.3 Failed Fuel Rod Storage Basket with 5.0 w/o 2"'U Fuel The failed fuel rod storage basket (FFRSB) may be filled with fresh or depleted fuel rods with a maximum initial enrichment of 5.0 w/o 235U. Fuel rods stored in the FFRSB may contain burnable absorbers, but it is not required. The FFRSB shall only be stored in the "All-Cell" storage configuration.

4.4 Reconstituted Fuel It is acceptable to store fuel meeting the storage requirements of any of the herein specified configurations, if that fuel has additionally been reduced in reactivity via reconstitution.

Modifications which without question would lower reactivity are the removal of fissile material (such as the removal of a fuel pin) and the subsequent replacement of fissile material with neutronically transparent or parasitic material.

4.5 Empty Cells For all configurations at Point Beach, an empty cell is permitted in any location of the spent fuel pool to replace an assembly since the water cell will decouple the neutronic interaction between the spent fuel assemblies in the pool. Non-fissile material and debris canisters (containing non-fissile material) may be stored in empty cells of all storage configurations.

4.6 Non-Fissile Equipment Non-fissile equipment, such as UT cleaning equipment, is permitted on top of the fuel storage racks, as such equipment will not increase reactivity in the spent fuel pool. This statement only relates to criticality safety concerns; thermal hydraulic or seismic considerations must be addressed separately.

4.7 Total Soluble Boron Requirement The soluble boron (with 19.9% '0B abundance) necessary to maintain kff less than or equal to 0.95 (including all biases and uncertainties) is 392 ppm. The soluble boron concentration required for a 1°1 atom percent equal to 19.4 (expected lowest pool value crediting I°B depletion) is 402 ppm. A total of 648 ppm of soluble boron (with 19.9% '0B abundance) is required to maintain klff less than or equal to 0.95 (including all biases and uncertainties) and assuming the most limiting single accident. The soluble boron concentration required for a 1°B atom percent equal to 19.4 (expected lowest pool value crediting 1LB depletion) is 664 ppm. The recommended minimum boron level is 664 ppm and is sufficient to accommodate all the design requirements.

Page 86 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 Table 4-1 Fuel Assembly Burnup versus Initial Enrichment for the "All-Cell" Storage Configuration Initial Limiting Burnup (MWD/MTU)

Enrichment 0 yr 5 yr 10 yr 15 yr 20 yr (w/o 235U) decay15 decay' 5 decay15 decay1 5

-decay15 2.13 0

0 0

0 0

3.0 8935 8493 8330 8051 7966 4.0 18475 17650 17172 16789 16554 5.0 27349 25965 25006 24355 23800 Note that the assembly bumups as a function of initial enrichment for each decay period are described by the following polynomials:

Assembly Burnup (0 yr decay) =

20 e& - 573 e 2 + 12811 e - 24881 Assembly Burnup (5 yr decay) = -34 e3 -

13 e2 +. 10506 e - 21990 Assembly Bumup (10 yr decay) = -39 e3 - 36 e2 + 10537 e - 21904 Assembly Bumup (15 yr decay) = -108 e3 + 710 e2 + 7764 e - 18715 Assembly Bumup (20 yr decay) = -128 e3 + 865 e2 + 7269 e - 18170

'5 Decay time is defined as the number of years since fuel assembly was last critical.

Page 87 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 Table 4-2 Fuel Assembly Burnup versus Initial Enrichment for the "l-out-of-4 5.0 w/o Fresh with no IFBA" Storage Configuration Initial Limiting Burnup (MWD/MTU)

Enrichment 0 yr 5yr 10 yr 15 yr 20 yr (w/o 235U) decay16 decay16 decay16 decay16 decay16 1.33 0

0 0

0 0

3.0 28193 25861 24513 23592 22681 4.0 40291 37453 35461 34316 33140 5.0 51169 48037 45589 44326 43205 Note that the assembly burnups as a function of initial enrichment for each decay period are described by the following polynomials:

Assembly Burnup (0 yr decay) = 322 e3 - 4474 e2 + 31502 e - 34741 Assembly Burnup (5 yr decay) = 260 e3 - 3624 e2 + 27340 e - 30563 Assembly Bumup (10 yr decay) = 269 e3 - 3638 e2 + 26461 e - 29391 Assembly Burnup (15 yr decay) = 250 e3 - 3357 e2 + 24973 e - 27864 Assembly Bumup (20 yr decay) = 265 e3 - 3377 e2 + 24293 e - 26960 16 Decay time is defined as the number of years since fuel assembly was last critical.

Page 88 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-N-P, Rev. 2 Table 4-3 Fuel Assembly Burnup versus Initial Enrichment for the "1-out-of-4 4.0 w/o Fresh with IFBA" Storage Configuration Initial Limiting Burnup (MWD/MTU)

Enrichment 0 yr 5 yr 10 yr 15 yr 20 yr (w/o 2 35U) decay17 decay17 decay17 decay 17 decay17 1.60 0

0 0

0 0

3.0 19883 18644 17595 16901 16783 4.0 31343 28908 27862 26759 26321 5.0 41361 39062 37517 36261 35293 Note that the assembly burnups as a function of initial enrichment for each decay period are described by the following polynomials:

Assembly Burnup (0 yr decay) = 124 e3 - 2209 e2 +

Assembly Burnup (5 yr decay) = 358 e3 - 4351 e2 +

Assembly Burnup (10 yr decay) = 192 e3 - 2610 e2 +

Assembly Burnup (15 yr decay) = 219 e3 - 2806 e2 +

Assembly Burnup (20 yr decay) = 217 e3 - 2887 e2 +

22335 e - 30589 27475 e - 34288 21433 e - 28398 21397 e - 27949 21718 e - 28247 17 Decay time is defined as the number of years since fuel assembly was last critical.

Page 89 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NIP, Rev. 2 Table 4-4 Number of IFBAs versus Initial Enrichment for the Fresh Fuel Assembly in the "1-out-of-4 4.0 w/o Fresh with IFBA" Storage Configuration Initial Enrichment Number of IFBAs (W/o 235U)

(1.0X) 4.0 0

4.5 19 5.0 39 Required Number of IFBA pins as a function of enrichment is given by the following polynomials:

Number of IFBA Pins = 2 e2 + 21 e - 116 Page 90 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 Table 4-5 Assembly Loading Requirements at the Interface between Different Storage Configurations Assembly that Must be Loaded at the Interface Configuration with Another Configuration's "All-Cell" Any "l-out-of-4 5.0 w/o Fresh with no IFBA" Only Depleted Fuel Assemblies "1-out-of-4 4.0 w/o Fresh with IFBA" Only Depleted Fuel Assemblies Instructions:

1. Identify which storage configurations will be interfaced.

2. Look up the assembly loading requirements for both storage configurations.

18An empty storage location is always permitted.

Page 91 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 This page intentionally left blank.

Page 92 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NIP, Rev. 2 A: Fuel Assembly meeting the requirements of Table 4-1 or Figure 4-7 for the "All-Cell" Storage Configuration Figure 4-1 Allowable Fuel Assemblies in the "All-Cell" Storage Configuration Page 93 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 This page intentionally left blank.

Page 94 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 LI : Fuel Assembly meeting the requirements of Table 4-2 and Figure 4-8 for the "l-out-of 4 5.0 w/o Fresh with no IFBA" Storage Configuration HI Fuel Assembly with 5.0 w/o Fresh in the "l-out-of 4 5.0 w/o Fresh with no IFBA" Storage Configuration Note: The 2x2 array is repeated with the same orientation Figure 4-2 Allowable Fuel Assemblies in the "1-out-of-4 5.0 w/o Fresh with no IFBA" Storage Configuration Page 95 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NIP, Rev. 2 This page intentionally left blank.

Page 96 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 L2 H2 L2 L2 L2 Fuel Assembly meeting the requirements of Table 4-3 or Figure 4-9 for the "1-out-of 4 4.0 w/o Fresh with IFBA" Storage Configuration H2 : Fuel Assembly with up to 5 w/o fresh with required IFBA per Table 4-4 and Figure 4-10 in the "1-out-of 4 4.0 w/o Fresh with IFBA" Storage Configuration Note: The 2x2 array is repeated with the same orientation.

Figure 4-3 Allowable Fuel Assembly Categories in the "l-out-of-4 4.0 w/o Fresh with IFBA" Storage Configuration Page 97 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 This page intentionally left blank.

Page 98 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 0ý I..

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A Li Li Li LI A

A A

H1 Li HI Li A

A A

LI LI Li LI A

A A

HI Li HI Li A

A A

A Fuel Assembly meeting the requirements of Table 4-1 or Figure 4-7 for the "All-Cell" Storage Configuration L I Fuel Assembly meeting the requirements of Table 4-2 and Figure 4-8 for the "1-out-of 4 5.0 w/o Fresh with no IFBA" Storage Configuration Hi Fuel Assembly with 5.0 w/o Fresh in the "I-out-of 4 5.0 w/o Fresh with no IFBA" Storage Configuration Figure 4-4 Allowable Interface between "All-Cell" and "1-out-of-4 5.0 w/o Fresh with no IFBA" Storage Configurations Page 99 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 This page intentionally left blank.

Page 100 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 CA i..

0

.4-0 4-0 A

A A

A A

A A

A A

A A

A A

A A

A A

A A

A A

L2 L2 L2 L2 A

A A

H2 L2 H2 L2 A

A A

L2 L2 L2 L2 A

A A

H2 L2 H2 L2 A

A A

A

Fuel Assembly meeting the requirements of Table 4-1 or Figure 4-7 for the "All-Cell" Storage Configuration L2

Fuel Assembly meeting the requirements of Table 4-3 or Figure 4-9 for the "1-out-of 4 4.0 w/o Fresh with IFBA" Storage Configuration H2 Fuel Assembly with up to 5.0 w/o fresh with required !FBA per Table 4-4 and Figure 4-10."1-out-of 4 4.0 w/o Fresh with IFBA" Storage Configuration Figure 4-5 Allowable Interface between "All-Cell" and "l-out-of-4 4.0 w/o Fresh with IFBA" Storage Configurations Page 101 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 This page intentionally left blank.

Page 102 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 0.0 4Lf Li Li Li Li Li Li Li Li HI LI Hi Li HI Li Li Li Li Li Li Li Li L2 L2 L2 L2 Li HI Li H2 L2 H2 L2 Li LI Li L2 L2 L2 L2 Li HI Li H2 L2 H2 L2 Li Li Li 0

0

~Jm 0

U, Li Fuel Assembly meeting the requirements of Table 4-2 or Figure 4-8 for the "I-out-of 4 5.0 w/o Fresh with no IFBA" Storage Configuration HI

Fuel Assembly with 5.0 w/o Fresh with No IFBA in the "1-out-of 4 5.0 w/o Fresh with no IFBA" Storage Configuration L2

Fuel Assembly meeting the requirements of Table 4-3 or Figure 4-9 for the "1-out-of 4 4.0 w/o Fresh with IFBA" Storage Configuration H2 Fuel Assembly with up to 5.0 w/o Fresh with required IFBA per Table 4-4. and Figure 4-10 "1 -out-of 4 4.0 w/o Fresh with JFBA" Storage Configuration Figure 4-6 Allowable Interface between "l-out-of-4 5.0 w/o Fresh with no IFBA" and "1-out-of-4 4.0 w/o Fresh with IFBA" Storage Configurations Page 103 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 This page intentionally left blank.

Page 104 of 116

Westinghouse Non-Proprietary Class 3

'WCAPA,65417NP, Rm X io 000.

Aý

.L.~

E L

L 0 yr dFcay o

-I.

1 I

l i

,!-4

-i---

4-4-i +i i

-d i44 4

4 +---4-4 4 4

/

/

1), nnA.

I I.

I I

. ý I I

I I

i i

i i

i i

i I

/

/ 10 5 y[ deca*y i10 yr decay 15 yr-decay

.20 yr decay 20,000 i1,00 5,000 0

[A'CEPTABLE.

F UNACC EPTAFBLE jIii.~i I1i-Al---

2.0 2.5.

3.0 3.5 4.0 MIitial 2"U Enr-ichmcnit(nominalw/Io) 4.5 5.0 Figure 4-7 Fuel Assembly Burnup versus Initial Enrichment for the "All Cell" Storage Configuration Page 105 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 This page intentionally left blank.

Page 106 of 116

Westinghouse Non-Proprietary Class 3 WCAP-1654 I 17NP,,Rev.. 1 1 55,000.

V]~VI~

III.

0Oyrdecay' 50,000' H-H HH-HH-H I I I 1,

.5 yr decay 10 yr decay 10 yr dTeay 20 yr edecy 40,000 35,000

'30, 000

' 25,000 20,000 15,900 10,000 5,000 0

J y Yi /Z/

I I

I I I"

IJ iI 1.0.

1.5 2:0 2.5 3.0 3.5 Initial 235U Enrichicnt (nominal w/o) 4.0, 4.5 5.0 Figure 4-8 Fuel Assembly Burnup versus Initial Enrichment for the "1-ut-of-4 5.0 W/o Fresh with no IFBA" Storage Configuration Page 107 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 This page intentionally left blank.

Page 108 of 116

Westinghouse Non-Proprietary Class 3 WCAP-,16541-NP,.Rev. 2 45,000 40,000 35,000

.30,000 i 25,o000 20,000 15,00Q 10,000 5,000 0

Of Y

~"0

-UIEMBLPEPL A:

I /I I

I I--I--I -

I L

0 yr. decay 5 yr decay 10 yr decay 15 yrdecay 20 yr decay 1.5 2.0 2.5 3.0 3.5 Initial "U Enri.iffient (ndmihalWi/o) 4.0 4.5 5.0 Figure 4-9 Fuel. Assembly Burnup versus Initial Enrichment for the "1-out-of-4 4.0 w/o Fresh with IFBA" Storage Configuration Page 109 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 This page intentionally left blank.

Page 110 of 116

Westinghouse Non-Proprietary Class 3

'WCAPýT6541-NP, Rev., 2 J*

4 1:3 z

E Iu 0/

ACCEPTABLE]

LNACC PTABLE

-[ii o--

I 4.0 4,2 4.4 4:6 4.8 5.0 Initial 235U Enrichment (nominal wi0)

Figure 4-10 IFBA Requirements for, the Fresh Fuel Assembly with Enrichments Greater than 4.0 w/o 235U in the "1-oUtýof-4 4.0 w/o with IFBA" Storage Configuration Page 111 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 This page intentionally left blank.

Page 112 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 5.0 Computer Codes Used In Calculation Table 5-1 Summary of Computer Codes Used in Point Beach Spent Fuel Pool Criticality Calculations Verified and Configured Outstanding per EP-310 or EP-313?

Basis (or reference) that Category A Error?

Code Code (Yes/No) or Configuration supports use of code in (Yes/No). If Yes, how No.

Code Name Version Control Reference current calculation acceptable?

SCALE-PC 4.4a See Footnote1 9 See Footnote' 9 See Note 2

PHOENIX-P 8.6.3 Yes Standard Westinghouse No Criticality Safety Depletion Lattice Code.

Notes:

1, NRC Information Notice 2005-13, "Potential Non-Conservative Error in Modeling Geometric Regions in the KENO-V.A Criticality Code", May 17, 2005 notifies of an errorin SCALE associated with cylindrical holes with shared boundaries. In the standard spent fuel pool analysis, none of the input files involve cylindrical holes with shared boundaries; therefore, the analysis is not affected from this code error.

2. NRC Information Notice 2005-31, "Potential Non-Conservative Error in Preparing Problem-Dependent Cross Sections for use with the KENO-V.a or KENO-VI Criticality Code", November 17, 2005". This programming error in SCALE version 5 does not cause erroneous results in current Westinghouse criticality analyses for the following reasons:

a. Westinghouse has not implemented SCALE version 5 for criticality analyses. All current analyses have been performed using SCALE 4.4 or earlier versions.

b. These options are only used for slab geometry (e.g.,. plate-type fuel), and Westinghouse analyses that are applicable to pressurized water reactor (PWR) and boiling water reactor (BWR) fuel lattices do not utilize this functionality.

19 Validation and benchmarking of the SCALE-PC Code package version 4.4a installation was performed as described in subsection 1.4.2. Verification of SCALE-PC Version 4.4a was achieved by running the sample test problems provided in the software package. Only differences in the outputs are due to time/date information and the header lines.

Page 113 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 This page intentionally left blank.

Page 114 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2 6.0 References I. Letter, G. S. Vissing (NRC) to R. C. Mecredy (RGE), "R. E. Ginna Nuclear Power Plant -

Amendment Re: Revision to the Storage Configuration Requirements within the Existing Storage Racks and Taking Credit for a Limited Amount of Soluble Boron,"

December 7, 2000.

2. M. L. Chawla (NRC), Prairie Island Nuclear Generating Plant, Units 1 And 2 - Issuance of Amendments Re: "Spent Fuel Pool Storage" (TAC Nos. MC5811 and MC5812)", February 5, 2006.

3. R. B. Ennis (NRC), "Millstone Power Station, Unit No. 2 - Issuance Of Amendment Re:

Spent Fuel Pool Requirements (TAC NO. MB3386)", April 1, 2003.

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

5. L. Kopp (NRC), "Guidance on the Regulatory Requirements for Criticality Analysis of Fuel Storage at Light-Water Reactor Power Plants," August 19, 1998.

6. Code of Federal Regulations, Title 10, Part 50, Section 68, "Criticality Accident Requirements."

7.

"SCALE 4.4a-Modular Code System for Performing Standardized Computer Analyses for Licensing Evaluation for Workstations and Personal Computers," RSICC CODE PACKAGE CCC-545, Oak Ridge National Laboratory, Oak Ridge, Tennessee, 2000.

8. T. C. Nguyen, et al, "Qualification of the PHOENIX-P/ANC Nuclear Design System for Pressurized Water Reactor Cores,"WCAP-1 1596-P-A, Revision 0, June 1988.

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

10. S. R. Bierman and E.D. Clayton, "Critical Experiments with Subcritical Clusters of 2.35 Wt% 23 WU Enriched U02 Rods in Water at a Water-to-Fuel Volume Ratio of 1.6,"

NUREG/CR-1547, PNL-3314, July 1980.

11. S.R. Bierman and E.D. Clayton, "Criticality Experiments with Subcritical Clusters of 2.35 and 4.31 Wt% 235U-Enriched U0 2 Rods in Water with Steel Reflecting Walls," Nuclear Technology, Vol. 54, pg. 131, August 1981.

12. International Handbook of Evaluated Criticality Safety Benchmark Experiments, Nuclear Energy Agency and Organization for Economic Cooperation and Development.

13. Not Used.

14. W. Marshall, et al., "Criticality Safety Criteria," TANS Vol. 35, pg. 278, 1980.

15. D. Lurie and R. Moore, "Applying Statistics", NUREG-1475, USNRC, February 1994.

16. Not Used.

17. Not Used.

18. "Recommendations for Addressing Axial Burnup in PWR Burnup Credit Analyses,"

NUREG/CR-6801, March 2003.

Page 115 of 116

Westinghouse Non-Proprietary Class 3 WCAP-16541-NP, Rev. 2

19. Not Used.

20. M. Ouisloumen, H. Huria, et al, "Qualification of the Two-Dimensional Transport Code PARAGON", WCAP-16045-P-A, August 2004 Page 116 of 116

ENCLOSURE7 FPL ENERGY POINT BEACH, LLC POINT BEACH NUCLEAR PLANT, UNITS I AND 2 LICENSE AMENDMENT REQUEST 247 SPENT FUEL POOL STORAGE CRITICALITY CONTROL WESTINGHOUSE AUTHORIZATION LETTER, ACCOMPANYING AFFIDAVIT, PROPRIETARY INFORMATION NOTICE, AND COPYRIGHT NOTICE CAW-08-2447 DATED JUNE 23, 2008 8 pages follow

0 Westinghouse Westinghouse Electric Company 1W Nuclear Services P.O. Box 35 5 Pittsburgh, Pennsylvania 15230-0355 USA U.S. Nuclear Regulatory Commission Direct tel: (412) 374-4643 Document Control Desk Directfax: (412) 374-3846 Washington, DC 20555-0001 e-mail: greshaja@westinghouse.com Our ref CAW-08-2447 June 23, 2008 APPLICATION FOR WITHIHOLDING PROPRIETARY INFORMATION FROM PUBLIC DISCLOSURE

Subject:

Submittal ofWCAP-16541-P, Rev. 2/ WCAP-16541-NP, Rev. 2 "Point Beach Units I and 2 Spent Fuel Pool Criticality Safety Analysis" (Proprietary/Non-proprietary)

The proprietary information for which withholding is being requested in the above-referenced report is further identified in Affidavit CAW-08-2447 signed by the owner of the proprietary information, Westinghouse Electric Company LLC. The affidavit, which accompanies this letter, sets forth the basis on which the information may be withheld from public disclosure by the Commission and addresses with specificity the considerations listed in paragraph (b)(4) of 10 CFR Section 2.390 of the Commission's regulations.

Accordingly, this letter authorizes the utilization of the accompanying affidavit by FPL Energy.

Correspondence with respect to the proprietary aspects of the application for withholding or the Westinghouse affidavit should reference this letter, CAW-08-2447, and should be addressed to J. A. Gresham, Manager, Regulatory Compliance and Plant Licensing, Westinghouse Electric Company LLC, P.O. Box 355, Pittsburgh, Pennsylvania 15230-0355.

Very truly yours, J. A. Gresham, Manager Regulatory Compliance and Plant Licensing Enclosures cc: Jon Thompson (NRC)

CAW-08-2447 bec: J. A. Gresham (ECE 4-7A) IL R. Bastien, 1 L (Nivelles, Belgium)

C. Brinkman, IL (Westinghouse Electric Co., 12300 Twinbrook Parkway, Suite 330, Rockville, MD 20852)

RCPL Administrative Aide (ECE 4-7A) IL, IA (letter and affidavit only)

R. Schmitt

CAW-08-2447 AFFIDAVIT COMMONWEALTH OF PENNSYLVANIA:

ss COUNTY OF ALLEGHENY:

Before me, the undersigned authority, personally appeared J. A. Gresham, who, being by me duly sworn according to law, deposes and says that he is authorized to execute this Affidavit on behalf of Westinghouse Electric Company LLC (Westinghouse), and that the averments of fact set forth in this Affidavit are true and correct to the best of his knowledge, information, and belief:

J/. A. Gresham, Manager Regulatory Compliance and Plant Licensing Sworn to and subscribed before me this 2 3rd day of June, 2008 Notary Public COMMONWEALTH OF PENNSYLVANIA Notarial Seal I Sharon L. Marki, Notary public Monroeville Born, Allegheny County 1 MY C-mmission Expfres Jan. 29, 2011 Member, Pennsylvania Association of Notaries

2 2 CAW-08-2447 (1) 1 am Manager, Regulator~y Compliance and Plant Licensing, in Nuclear Services, Westinghouse Electric Company LLC (Westinghouse), and as such, I have been specifically delegated the function of reviewing the proprietary information sought to be withheld from public disclosure in connection with nuclear power plant licensing and rule making proceedings, and am authorized to apply for its withholding on behalf of Westinghouse.

(2) 1 am making this Affidavit in conformance with the provisions of 10 CFR Section 2.390 of the Commission's regulations and in conjunction with the Westinghouse "Application for Withholding" accompanying this Affidavit.

(3) 1 have personal knowledge of the criteria and procedures utilized by Westinghouse in designating information as a trade secret, privileged or as confidential commercial or financial information.

(4)

Pursuant to the provision s of paragraph (b)(4) of Section 2.390 of the Commission's regulations, the following is furnished for consideration by the Commission in determining whether the information sought to be withheld from public disclosure should be withheld.

Wi The information sought to be withheld from public disclosure is owned and has been held in confidence by Westinghouse.

(ii)

The information is of a type customarily held in confidence by Westinghouse and not customarily disclosed to the public. Westinghouse has a rational basis for determining the types of information customarily held in confidence by it and, in that connection, utilizes a system to determine when and whether to hold certain types of information in confidence.

The application of that system and the substance of that system constitutes Westinghouse policy and provides the rational basis required.

Under that system, information is held in confidence if it falls in one or more of several types, the release of which might result in the loss of an existing or potential competitive advantage, as follows:

(a)

The information reveals the distinguishing aspects of a process (or component, structure, tool, method, etc.) where prevention of its use by any of Westinghouse's competitors without license from Westinghouse constitutes a competitive economic advantage over other companies.

3 CAW-08-2447 (b)

It consists of supporting data, including test data, relative to a process (or component, structure, tool, method, etc.), the application of which data secures a competitive economic advantage, e.g., by optimization or improved marketability.

(C)

Its use by a competitor would reduce his expenditure of resources or improve his competitive position in the design, manufacture, shipment, installation, assurance of quality, or licensing a similar product.

(d)

It reveals cost or price information, production capacities, budget levels, or commercial strategies of Westinghouse, its customers or suppliers.

(e)

It reveals aspects of past, present, or future Westinghouse or customer funded development plans and programs of potential commercial value to Westinghouse.

(f)

It contains patentable ideas, for which patent protection may be desirable.

There are sound policy reasons behind the Westinghouse system which include the following:

(a)

The use of such information by Westinghouse gives Westinghouse a competitive advantage over its competitors. It is, therefore, withheld from disclosure to protect the Westinghouse competitive position.

(b)

It is information that is marketable in many ways. The extent to which such information is available to competitors diminishes the Westinghouse ability to sell products and services involving the use of the information.

(C)

Use by our competitor would put Westinghouse at a competitive disadvantage by reducing his expenditure of resources at our expense.

(d)

Each component of proprietary information pertinent to a particular competitive advantage is potentially as valuable as the total competitive advantage. If competitors acquire components of proprietary information, any one component may be the key to the entire puzzle, thereby depriving Westinghouse of a competitive advantage.

4 CAW-08-2447 (e)

Unrestricted disclosure would jeopardize the position of prominence of Westinghouse in the world market, and thereby give a market advantage to the competition of those countries.

(f)

The Westinghouse capacity to invest corporate assets in research and development depends upon the success in obtaining and maintaining a competitive advantage.

(iii)

The information is being transmitted to the Commission in confidence and, under the provisions of 10CFR Section 2.390, it is to be received in confidence by the Commission.

(iv)

The information sought to be protected is not available in public sources or available information has not been previously employed in the same original manner or method to the best of our knowledge and belief.

(v)

The proprietary information sought to be withheld in this submittal is that which is appropriately marked in WCAP-16541-P, Revision 2, "Point Beach Units 1 and 2 Spent Fuel Pool Criticality Safety Analysis" (Proprietary), dated June 23, 2008, for Point Beach Units 1 and 2, being transmitted by the FPL Energy letter and Application for Withholding Proprietary Information from Public Disclosure, to the Document Control Desk. The proprietary information as submitted by Westinghouse for Point Beach Units 1 and 2 is expected to be applicable for other licensee submittals in response to certain NRC requirements forjustification of Spent Fuel Pool Criticality Safety Analysis.

This information, is part of that which will enable Westinghouse to:

(a) Support justification of the spent fuel pool criticality safety analysis.

Further this information has substantial commercial value as follows:

(a)

Westinghouse plans to sell the use of similar information to its customers for purposes of spent fuel pool criticality analyses.

(b)

Westinghouse can sell support and defense of spent fuel pool criticality analyses.

5 CAW-08-2447 (c)

The information requested to be withheld reveals the distinguishing aspects of a methodology which was developed by Westinghouse.

Public disclosure of this proprietary information is likely to cause substantial harm to the competitive position of Westinghouse because it would enhance the ability of competitors to provide similar calculations and licensing defense services for commercial power reactors without commensurate expenses. Also, public disclosure of the information would enable others to use the information to meet NRC requirements for licensing documentation without purchasing the right to use the information.

The development of the technology described in part by the information is the result of applying the results of many years of experience in an intensive Westinghouse effort and the expenditure of a considerable sum of money.

In order for competitors of Westinghouse to duplicate this information, similar technical programs would have to be performed and a significant manpower effort, having the requisite talent and experience, would have to be expended.

Further the deponent sayeth not.

PROPRIETARY INFORMATION NOTICE Transmitted herewith are proprietary and/or non-proprietary versions of documents furnished to the NRC in connection with requests for generic and/or plant-specific review and approval.

In order to conform to the requirements of 10 CFR 2.390 of the Commission's regulations concerning the protection of proprietary information so submitted to the NRC, the information which is proprietary in the proprietary versions is contained within brackets, and where the proprietary information has been deleted in the non-proprietary versions, only the brackets remain (the information that was contained within the brackets in the proprietary versions having been deleted). The justification for claiming the information so designated as proprietary is indicated in both versions by means of lower case letters (a) through (f) located as a superscript immediately following the brackets enclosing each item of information being identified as proprietary or in the margin opposite such information. These lower case letters refer to the types of information Westinghouse customarily holds in confidence identified in Sections (4)(iiXa) through (4)(ii)(f) of the affidavit accompanying this transmittal pursuant to 10 CFR 2.390(b)(1).

COPYRIGHT NOTICE The reports transmitted herewith each bear a Westinghouse copyright notice. The NRC is permitted to make the number of copies of the information contained in these reports which are necessary for its internal use in connection with generic and plant-specific reviews and approvals as well as the issuance, denial, amendment, transfer, renewal, modification, suspension, revocation, or violation of a license, permit, order, or regulation subject to the requirements of 10 CFR 2.390 regarding restrictions on public disclosure to the extent such information has been identified as proprietary by Westinghouse, copyright protection notwithstanding. With respect to the non-proprietary versions of these reports, the NRC is permitted to make the number of copies beyond those necessary for its internal use which are necessary in order to have one copy available for public viewing in the appropriate docket files in the public document room in Washington, DC and in local public document rooms as may be required by NRC regulations if the number of copies submitted is insufficient for this purpose. Copies made by the NRC must include the copyright notice in all instances and the proprietary notice if the original was identified as proprietary.