Text

Westinghouse, WCAP-17400-NP, Supplement 1, Rev. 1, Prairie Island, Units 1 and 2 Spent Fuel Pool Criticality Analysis, Supplemental Analysis for the Storage of Ifba Bearing Fuel.
	ML15327A229
Person / Time
Site:	Prairie Island
Issue date:	10/31/2015
From:	Wenner M T; Westinghouse
To:	; Office of Nuclear Reactor Regulation
Shared Package
ML15327A244	List: L-PI-15-087, Enclosures 7 & 8: Modeling of Fuel Assemblies Containing Both Ifba and Gadolinia Absorber Rods with Westinghouse Core Design Code Systems and Affidavit; ML15327A228; ML15327A229;
References
	L-PI-15-087 WCAP-17400-NP, Suppl 1, Rev 1
	Download: ML15327A229 (53)
	v • d • e

L-PI-1 5-087 NSPM Enclosure 5 Enclosure 5 Westinghouse WCAP-1 7400-NP Supplement 1 Revision 1 Prairie Island Units I and 2 Spent Fuel Pool Criticality Analysis Supplemental Analysis for the Storage of IFBA Bearing Fuel Non-Proprietary October 2015 Errata:* Page 4-12 provides a reference to the Technical Specification minimum boron concentration that requires clarification.

This text on page 4-12 suggests that the proposed Technical Specification limit (with uncertainty) is 2400 ppm. In fact, the proposed TS limit (as shown in Enclosure

2) is 2500 ppm.52 pages follow Westinghouse Non-Proprietary Class 3 WCAP-1 7400-NP October 2C Supplement 1, Revision 1 Prairie Island Units 1 and 2 Spent Fuel Pool Criticality Safety Analysis Supplemental Analysis for the Storage of IFBA Bearing Fuel Westinghouse

)1 5 WESTINGHOUSE NON-PROPRIETARY CLASS 3 WCAP-17400-NP Supplement 1, Revision 1 Prairie Island Units 1 and 2 Spent Fuel Pool Criticality Safety Analysis Supplemental Analysis for the Storage of IFBA Bearing Fuel Michael T. Wenner*Core Engineering

& Software Development October 2015 Reviewer:

Mykola Boychenko*

Core Engineering

& Software Development Approved:

Edmond J. Mercier*, Manager Core Engineering

& Software Development

Electroniically approved records are authenticated in the electronic document management system.Westinghouse Electric Company LLC 1000 Westinghouse Drive Cranberry Township, PA 16066, USA© 2015 Westinghouse Electric Company LLC All Rights Reserved ii REVISION HISTORY Revision Description and Impact of the Change Date 0-A Original Draft Issue 09/2015 0 Original Issue 10/20 15 1 Revision 1 to correct the normal operations Fuel Not Operating in Cycles 10/2015 1-4 soluble boron concentration from Table S$6-7. Other minor editorial updates included.TRADEMARK NOTICE Optimized ZIRLOTM and ZIRLO are trademarks or registered trademarks of Westinghouse Electric Company LLC, its affiliates and/or its subsidiaries in the United States of America and may be registered in other countries throughout the world. All rights reserved.

Unauthorized use is strictly prohibited.

Other names may be trademarks of their respective owners.WCAP- 17400-NP October 2015 Supplement 1, Revision 1 iii TABLE OF CONTENTS LIST OF TABLES .................................................................................................

v LIST OF' FIGURES ..............................................................................

................

vii LIST OF ACRONYMS, INITIALISMS, AND TRADEMARKS............................................

viii Si1. iNTRODUCTION......................................................................................

1-1 S2. OVERVIEW ............................................................................................

2-1i S2.1 ACCEPTANCE CRITERIA..................................................................

2-1 S2.2 DESIGN APPROACH........................................................................

2-1 S2.3 COMPUTER CODES.........................................................................

2-2 S2.3.1 Two-Dimensional Transport Code PARAGON..................................

2-2 S2.3.2 SCALE Code Package.............................................................

2-2 S3. ANALYSIS INPUT SELECTION

....................................................................

3-1 S3.1 FUEL ASSEMBLY INFORMATION........................................................

3-1 S3.l.1 Fuel Assembly Modeling Assumptions

..........................................

3-2 S3.2 FUEL STORAGE CELL & RACK DESCRIPTION.......................................

3-3 S3.2.1 Fuel Storage Cell & Rack Modeling Assumptions

..............................

3-3 S3.3 FUEL DEPLETION PARAMETER SELECTION.........................................

3-4 S3.3.1 Fuel Isotopic Generation..........................................................

3-4 S3.3.2 Reactor Operation Parameters

....................................................

3-4 S3.3.3 Axial Profile Selection.............................................................

3-5 S3.3.4 Burnable Poison Design...........................................................

3-7 S3.3.5 Fuel Depletion Modeling Assumptions

..................................

........3-7 S3.4 RODDED OPERATION......................................................................

3-8 S3.5 CREDIT FOR RCCAS .......................................................................

3-8 S3.6 NORMAL CONDITION DESCRIPTION:.

................................................

3-8 S3.6.1 Type I Normal Conditions........................................................

3-8 S3.6.2 Type 2 Normal Conditions........................................................

3-8 S3.6.3 Type 3 Normal Conditions........................................................

3-8 S3.6.4 Type 4 Normal Conditions........................................................

3-9$3.6.5 Type 5 Normal Conditions........................................................

3-9 S3.7 KENO MODELlING ASSUMPTIONS

......................................................

3-9 S3.7.1I Array Descriptions.................................................................

3-9 S3.8 ACCIDENT DESCRIPTION...............................................................

3-11 S4. ANALYSIS DESCRIIPTION

& CALCULATIONS..................................................

4-1 S4.1 BURNUP LIMIT GENERATION

...........................................................

4-1 S4.1.1 Target Calculation Description

...............................................

4-1 S4.1.2 Biases & Uncertainties Calculations

.............................................

4-1 S4.2 SOLUBLE BORON CREDIT ...............................................................

4-9 S4.3 RODDED OPERATION

....................................................................

4-10 S4.4 NORMAL CONDITIONS

..................................................................

4-10 S4.4.1 Type 1 Normal Conditions

......................................................

4-10 S4.4.2 Type 2 Nonrmal Conditions

......................................................

4-10 S4.4.3 Type 3 Nonnal Conditions

......................................................

4-10 WCAP- 17400-NP October 2015 Supplement 1, Revision 1 iv S4.4.4 Type 4 Normal Conditions

......................................................

4-11$4.4.5 Type 5 Normal Conditions

......................................................

4-11 S4.5 ACCIDENTS.................................................................................

4-11 S4.5. 1 Assembly Misloads into the Storage Racks....................................

4-Il S4.5.2 Inadvertent Removal of an RCCA ..............................................

4-12 S4.5.3 Spent Fuel Temperature Outside Operating Range ............................

4-12$4.5.4 Dropped & Misplaced Fresh Assembly.........................................

4-12 S5. ANALYSIS RESULTS.................................................................................

5-1 S5.1 BURNUP LIMITS & RESTRICTIONS ON STORAGE ARRAYS ......................

5-1 S5.1.1 Requirements for IFBA Bearing Fuel ............................................

5-2 S5.1.2 Bumup Requirements for Fuel Operated during Cycles 1-4 ...................

5-7 S5.1.3 Decay Time Interpolation

.........................................................

5-7 S5.2 RODDED OPERATION......................................................................

5-7 S5.3 INTERFACE CONDITIONS

................................................................

5-7 S5.4 NORMAL CONDITIONS....................................................................

5-7 S5.4.1 Type 1 Normal Conditions........................................................

5-7 S5.4.2 Type 2 Normal Conditions........................................................

5-7 S5.4.3 Type 3 Normal Conditions........................................................

5-7 S5.4.4 Type 4 Normal Conditions........................................................

5-7 S5.4.5 Type 5 Normal Conditions........................................................

5-8 S5.5 SOLUBLE BORON CREDIT................................................................

5-8 S6. COMPARISON WITH "FUJEL NOT OPERATED IN CYCLES 1-4" BURNUP LIMITS .......6-1 S6.1 FINAL STORAGE (BURNUJP)

LIMIT COMPARISON

..................................

6-1 S6.2 METHODOLOGY AND INPUT COMPARISON..........................................

6-4 S6.2.1 Methodology Comparison

........................................................

6-4] $~~6.2.2 Input Comparison and Conclusion

...............................................

6-4 S6.2.3 Accidents and Soluble Boron Credit Review....................................

6-6 S6.2.4 Comparison Conclusions..........................................................

6-6 S7. REFERENCES

.........................................................................................

7-1 APPENDIX A VALIDATION OF SCALE 5.1 ..............................................................

A-i1 WCAP- 17400-NP October 2015 Supplement 1, Revision 1 V LIST OF TABLES Table $2-1 Fuel Categories Ranked by Reactivity................................................................

Table $3-1 422V+ Fuel Assembly Specifications.............................................................

3-2 Table $3-2 Design Basis Fuel Assembly Design Specifications..............................................

3-3 Table $3-3 Axial Burnup and Moderator Temperature Profiles ..............................................

3-6 Table S3-4 IFBA Specifications.................................................................................

3-7 Table S3-5 Additional Parameters Used in IFBA Bearing Fuel Depletion Analysis........................

3-7 Table $4-1 Biases & Uncertainties for Array A IFBA Bearing Fuel.........................................

4-4 Table $4-2 Biases & Uncertainties for Array B IFBA Bearing Fuel .......................................

.4-5 Table $4-3 Biases & Uncertainties for Array D IFBA Bearing Fuel .......................................

4-6 Table $4-4 Biases & Uncertainties for Array E IFBA Bearing Fuel......................................4-7 Table $4-5 Biases & Uncertainties for Array G IFBA Bearing Fuel .....................................

.4-8 Table S4-6 [ ]a ....................................................

4-10 Table S4-7 [ ] \. ..........................

4-12 Table $5-1 Fuel Categories Ranked by Reactivity.........................................................

5-i Table S5-2 Fuel Category 2 Burnup Requirement Coefficients

............................................

5-2 Table $5-3 Fuel Category 2 Bumnup Requirements (GWd/MTU)

........................................

..5-2 Table $5-4 Fuel Category 3 Bumup Requirement Coefficients............................................

5-3 Table $5-5 Fuel Category 3 Burnup Requirements (GWd/MTU)

..........................................

5-3 Table S5-6 Fuel Category 4 Bumnup Requirement Coefficients.

.........................................

5-4 Table $5-7 Fuel Category 4 Burnup Requirements (GWd/MTU).........................................

5-4 Table $5-8 Fuel Category 5 Bumnup Requirement Coefficients.

...........................................

5-5 Table $5-9 Fuel Category 5 Burnup Requirements (GWdIMTU)

..........................................

5-5 Table S5-l0 Fuel Category 6 Burnup Requirement Coefficients.

.........................................

5-6 Table $5-11 Fuel Category 6 Bumup Requirements (GWd/MTU)......................................

5-6 Table $6-1 Fuel Category 2 Burnup Requirements Comparison (GWd/MTU), ..........................

6-2 Table $6-2 Fuel Category 3 Bumnup Requirements Comparison (GWd/MTU)..........................

6-2 Table $6-3 Fuel Category 4 Burnup Requirements Comparison (GWd!MTU)............................

6-3 Table $6-4 Fuel Category 5 Bumup Requirements Comparison (GWd/MTU)

...........................

6-3 Table $6-5 Fuel Category 6 Burnup Requirements Comparison (GWd/MTU)............................

6-4 WCAP-l 7400-NP October 2015 Supplement 1, Revision 1 vi Table $6-6 Comparison of Input Core Operational Parameters During Depletion.

........................

6-5 Table S6-7 Soluble Boron Credit Comparison.

..............................................................

6-6 WCAP-17400-NP October 2015 Supplement 1, Revision 1 vii LIST OF FIGURES Figure $3-1 Allowable Storage Arrays..........................................................................

3-10 WCAP- 17400-NP October 2015 Supplement 1, Revision 1 viii LIST OF ACRONYMS, INITIALISMS, AND TRADEMARKS 422V+at%BA BPRA EPU gpm GT GWd ID IFBA IT keff KENO MTU MWd MWt OD pcm ppm Prairie Island psia RCCA SFP TD Westinghouse wt%yr 422 Vantage +Atom Percent Burnable Absorber Burnable Poison Rod Assembly Extended Power Uprate Gallons per Minute Guide Tube Gigawatt days Inner Dimension (Diameter)

Integral Fuel Burnable Absorber Instrumentation Tube Effective neutron multiplication factor SCALE Module KENO V.a Metric Ton Uranium Megawatt-day Megawatts thermal Outer Dimension (Diameter) percent millirho parts per million (by weight)Prairie Island Nuclear Generating Plant Pounds Per Square Inch Absolute Rod Cluster Control Assemblies Spent Fuel Pool Theoretical Density Westinghouse Electric Company LLC Weight Percent Year WCAP- 17400-NP October 2015 Supplement 1, Revision 1 1-1 Si. INTRODUCTION The Prairie Island Spent Fuel Pool (SFP) criticality analysis, as documented in the License Amendment Issuance, U.S. Nuclear Regihlatory Commission Accession Number ML13241A383 (Reference 1), supported by WCAP-1 7400-P, "Prairie Island Units 1 and 2 Spent Fuel Pool Criticality Safety Analysis," (Reference

2) has been reviewed and approved by the U.S. Nuclear Regulatory Conmission.

The purpose of this report is to document the additional criticality safety analysis performed to support the storage of fuel containing Integral Fuel Burnable Absorber (IFBA) as part of a fuel design transition for Prairie Island Nuclear Generating Plant Units 1 and 2. This analysis is necessary because of the spent fuel pooi reactivity change associated with WFBA bearing fuel compared to non-JFBA bearing fuel, due to spectral hardening as the dominant reactivity effect, while not crediting any residual absorber in the spent fuel pool for storage.Fuel not containing IFBA, including fuel containing Gadolinia, may be present in the core at the same time as fuel containing WFBA. Fuel which contained IFBA during depletion will bound fuel not containing

[FBA during depletion with regard to reactivity in the SFP due to the spectral hardening that occurs when IWBA is present from increased thermal absorption.

Consequently, burnup limits derived for fuel containing JFBA can be applied to fuel not containing IFBA within the same core. For simplicity all fuel in a core operated with IFBA will be referred to as IFBA bearing fuel from here onward.This supplemental report includes all additional analysis necessary to support the storage of IFBA bearing fuel and follows the general methodology outlined in Reference

2. Any deviation or input change related specifically to the IFBA bearing fuel analysis is thoroughly detailed.

The supplement report documentation format generally follows the original analysis documentation format, section by section.Notwithstanding, redundant documentation in terms of general methodology is avoided and Reference 2 is referred to when appropriate.

The following remarks clarify sections (equivalent in WCAP-17400) with headings which have changed.* Section 3.3.4, Burnable Poison Usage from Reference 2 corresponds with Section S3.3.4, Burnable Poison Design* Section 4.1.2.1.4, Fission Product Worth Uncertainty from Reference 2 corresponds with Section S4.1.2.1.4, Fission Product Worth and Actinide Bias as a result of a methodology change in the treatment of minor actinide and fission product nuclides for which adequate critical experiment data are not available.

Section 4.1.2.2.1, Storage Array Biases and Uncertainties for Fuel Not Operated During Cycles 1-4 from Reference 2 is updated to S4.l.2.2.1, Storage Array Biases & Uncertainties for JFBA Bearing Fuel.* Section 4.5.1, Assembly Misload into the Storage Racks of Reference 2 is updated to Section S4.5.1, Assembly Misloads into the Storage Racks; two subsections are added as follows: o Section $4.5.1.1, Single Assembly Misload into the Storage Racks o Section S4.5.l.2, Multiple Assembly Misload into the Storage Racks* Section 5.1.1, Requirements for Fuel Not Operated during Cycles 1-4 was updated to Section S5.l.l, Requirements for IFBA Bearing Fuel.* Section S6 and its subsections have been added to discuss the validity of utilizing TFBA bearing fuel bumnup limits to bound Fuel Not Operated in Cycles 1-4 from Reference 2.WCAP- 17400-NP October 2015.Supplement 1, Revision 1 1-2* The References Section has been moved from Section 6 to Section 7 (Section $7).All calculations containing soluble boron performed for this supplemental analysis assumes the at% of'°B in boron to be 19.4%, whereas in Reference 2, 19.9% at% was assumed, with an equivalent ppm value of 19.4 at% determined.

Finally, this document concludes with an assessment of the application of bumup limits developed for JFBA bearing fuel for Fuel Not Operated in Cycles 1-4 from Reference

2. Cycles 1-4 did not contain IFBA and therefore no comparison is necessary for burnup limits associated with cycles 1-4.WCAP- 17400-NP October 2015 Supplement 1, Revision 1 2-1$2. OVERVIEW See Section 2 of Reference

2. The presence of IFBA bearing fuel does not impact the overview.$2.1 ACCEPTANCE CRITERIA The objective of this SFP criticality safety analysis is to ensure that the pooi operates within the bounds discussed here.1. All calculations of the effective neutron multiplication factor (ks,.) performed for permissible storage arrangements at a soluble boron concentration of 0 ppm yield results less than 1.0 including margin for all applicable biases and uncertainties with 95% probability at a 95%confidence level.2. All calculations of the effective neutron multiplication factor (ken) performed for permissible storage arrangements at a soluble boron concentration of 400' ppm yield results less than 0.95 including margin for all applicable biases and uncertainties with 95% probability at a 95%confidence level.3. The analysis demonstrates that is less than 0.95 under all postulated accident conditions with a soluble boron concentration of less than 24002 ppm. This criterion shall also be met including margin for all applicable biases and uncertainties with 95% probability at a 95%confidence level.$2.2 DESIGN APPROACH Table S2-1 lists the fuel categories ranked by reactivity evaluated for IFBA bearing fuel.Table $2-1 Fuel Categories Ranked by Reactivity Fuel Category 1 High Reactivity Fuel Category 2 Fuel Category 3 Fuel Category 4 Fuel Category 5 Fuel Category 6 Low Reactivity Notes: 1. Fuel categories are ranked in order of decreasing reactivity, e.g., Fuel Category 2 is less reactive than Fuel Category 1, etc.2. Fuel Category 1 is fuel up to 5.0 wt% 2 3 5 U; no burnup is required.3. Fuel Categories 2 through 6 are determined from the coefficients provided in Section S5. 1.1 The limiting configuration in this supplemental analysis requires a minimum soluble boron concentration of 340 ppm; however, to provide margin, the associated Technical Specifications (TS 4.3.1) may require any value between 340 ppm and the assumed boron dilution analysis endpoint.

400 ppm has been chosen as that value.2lBased on a Proposed Tech. Spec. limit of 2500 ppm with 100 ppm uncertainty.

WCAP- 17400-NP October 2015 Supplement 1, Revision 1 2-2 Category 7 fuel (Reference

2) addresses consolidated fuel assemblies.

Since there are no plans to consolidate fuel in the future, Category 7 fuel is not evaluated for IFBA bearing fuel, and as such, there are no storage limits developed for Category 7 IFBA bearing fuel. See Section 2.2 of Reference 2 for additional details of the design approach.S2.3 COMPUTER CODES The computer codes used in this analysis have not changed. See Section 2.3 of Reference 2.S2.3.1 Two-Dimensional Transport Code PARAGON See Section 2.3.1 of Reference 2.$2.3.1.1 PARAGON Cross-Section Library See Section 2.3.1.1 of Reference 2.$2.3.2 SCALE Code Package See Section 2.3.2 of Reference 2.$2.3.2.1 SCALE 44-Group Cross-Section Library See Section 2.3.2.1 of Reference 2.WCAP- 17400-NP October 2015 Supplement 1, Revision 1 3-1 53. ANALYSIS INPUT SELECTION See Section 3 of Reference 2.$3.1 FUEL ASSEMBLY INFORMATION Prairie Island has operated using several different fuel assembly designs manufactured by Westinghouse Electric Company LLC (Westinghouse) as well as fuel assembly designs manufactured by Exxon Nuclear Fuel.The fuel assemblies for Prairie Island incorporate 14x14 square arrays of 179 fuel rods with 16 control rod guide tubes (GTs) and one instrumentation tube (IT). The fuel rod cladding is Zircaloy or ZIRLOtubes including Optimized ZIRLO T M High Performance Cladding Material and other variants.

Each standard fuel rod contains a column of enriched U0O fuel pellets. The pellets are pressed and sintered and are dished on both ends. Gadolinia bearing fuel rods, when part of the fuel assembly design, contain U0 2-Gd 2 O 3 fuel pellets (see Section S3.3.4). IFBA bearing fuel rods, when part of the fuel assembly design, contains a thin coating of zirconium diboride (ZrB 2) coating on the pellet cylindrical surface.In Reference 2, the different fuel designs used at Prairie Island were analyzed to determine the limiting fuel assembly design with respect to criticality safety. The limiting fuel assembly design was used to develop the isotopic number densities and develop bumnup limits. For this supplement analysis, the 422V+fuel design will be the only design considered.

This is because the 422V+ fuel design is the current fuel design and there are no plans to transition to another fuel type in the foreseeable future. This fuel design currently utilizes Gadolinia bearing fuel rods and this supplemental analysis evaluates*

the inclusion of IFBA bearing fuel rods. Table $3-1 contains fuel assembly specifications of the 422V+ fuel design.WCAP-1 7400-NP October 2015 Supplement 1, Revision 1 3-2 Table $3-1 422V+ Fuel Assembly Specifications Parameter Value Assembly type 422V+Rod array size 14x14 Rod pitch, inch 0.556 Active fuel length, inch 143.25 Stack density, % TD [ ].Maximum enrichment, wt% 2 3 5 U 4.95 Total number of fuel rods 179 Fuel cladding OD, inch 0.4220 Fuel cladding ID, inch 0.3734 Fuel cladding thickness, inch 0.0243 Pellet diameter, inch 0.3 659 Number of guide/instrument tubes 16 / 1 Guide/instrument tube OD, inch 0.5260 / 0.4220 Guide/instrument tube ID, inch 0.4920./0.3740 Guide/instrument tube thickness, inch 0.0170 / 0.0240 Max ]IFBA Rods 120 Max IFBA Thickness, mg '°B/inch [ $3.1.1 Fuel Assembly Modeling Assumptions See Section 3.1.1 of Reference 2.[I]a~C See Section $4.2 for more details of the soluble boron requirements.

Table S3-2 summarizes the specifications of the 422V+ fuel design including IFBA and the specifications used in the criticality safety analysis.

Table S3-2 includes the increased fuel theoretical density (TD)utilized with IFBA bearing fuel. This has been chosen to bound any future TD increase in fuel manufacturing.

WCAP- 1 7400-NP October 2015 Supplement 1, Revision 1 3-3 Table $3-2 Design Basis Fuel Assembly Design Specifications Parameter Value (422V+) Value (Analyzed)

Assembly type 14x 14 422 Vantage + 14x 14 422 Vantage +Rod array size 14x14 14x14 Rod pitch, inch 0.556 [ ]ac 0.556 [ ]~Active fuel length, inch 143.25 144 Stack density, % TD [ ]a,c Maximum enrichment, wt% 2 3 5 U 4.95 5.0 Enrichment tolerance, wt% 2 3 5 U [I ]([ ]Total number of fuel rods 179 179 Fuel cladding OD, inch 0.422 [ ]a.C 0.422 [ ]'Fuel cladding ID, inch 0.3 734 [ ] 0.3 734 [ ]ac Fuel cladding thickness, inch 0.0243 [ ]a.C 0.0243 [ ],, Pellet diameter, inch .0.3659 [ 0.3659 []'Number of guide/instrument tubes 16 / 1 16 / 1 Instrument tube OD, inch 0.4220 [ 0.4220 [ ], Instrument tube ID, inch 0.3740 [ ] 0.3740 [ ]'Instrument tube thickness, inch 0.0240 [ ]fl.C 0.0240 [ ]].C Guide tube OD, inch 0.5260 [ ]ac¢ 0.5260 [ ]a'c Guide tube ID, inch 0.4920 [ ] 0.4920 [ ]'Guide tube thickness, inch 0.0 17 [ 0.0 17 [ ]'C Max IFBA Rods 120 120 BA l° loading, mg/inch [ ]a'c [ ]a'c BA Thickness, mils [ ] [ ]a'c BA length, inches [ ] ]a.,o$3.2 FUEL STORAGE CELL & RACK DESCRIPTION See Section 3.2 of Reference 2.$3.2.1 Fuel Storage Cell & Rack Modeling Assumptions See Section 3.2.1 of Reference 2.WC'1 740N]ac WCAP-1 7400-NP October 2015 Supplement 1, Revision 1 3-4 S3.3 FUEL DEPLETION PARAMETER SELECTION The analysis performed in Reference 2 was to support a proposed Extended Power Uprate (EPU) as well as address non-conservatisms that were present in the prior SFP analysis.

An EPU was never actually performed.

For conservatism, input to the SFP criticality analysis continued to assume EPU conditions such that for many depletion parameter input values, EPU conditions are assumed which carry forth into this supplement analysis and provide additional conservatism for the overall SFP criticality analysis.]a,c S3.3.1 Fuel Isotopic Generation The methodology for generating isotopic number densities to support bumup credit in this analysis is based on in-reactor operation (actual and planned including with IFBA bearing fuel) at bounding operating conditions.

See Section 3.3.1 of Reference 2 for additional general details. Burnable Poison Rod Assemblies (BPRAs), present only in Cycles 1-4, were accounted for in the burnup requirements provided for fuel operated during Cycles 1-4 in Reference

2. With no intention to use BPRAs in the future, they are not evaluated for use with IFBA bearing fuel.S3.3.2 Reactor Operation Parameters See Section 3.3.2 of Reference 2 for the reactor operation parameters introduction.

The nominal reactor operation parameter input used for the IFBA Bearing Fuel Depletion Analysis as well as a listing of the Reference 2 nominal operating parameter input for comparison are given in Table S3-5.$3.3.2.1 Soluble Boron Concentration See Section 3.3.2.1 of Reference 2.IIIc S3.3.2.2 Fuel Temperature

[I]a~C See Section 3.3.2.2 of Reference 2 for additional details.WCAP-1I7400-NP October 2015 Supplement 1, Revision 1 3-5 S3.3.2.3 Operating History and Specific Power[I],,C See Section 3.3.2.3 of Reference 2 for additional details.$3.3.3 Axial Profile Selection This section discusses the selection of bounding axial bumup and moderator temperature profiles.

[I]a,c S3.3.3.1 Axial Burnup Profile Selection The selection of axial burnup profiles utilized the same basic methodology as outlined in Section 3.3.3.1 of Reference

2. [$3.3.3.2 Axial Moderator Temperature Profile Selection The selection of axial moderator temperature profiles utilized the same basic methodology as outlined in Section 3.3.3.2 of Reference 2.[]'C The limiting temperature profiles selected are summarized in Table S3-3.S3.3.3.3 Axial Burnup and Temperature Profiles[]a,C WCAP- 17400-NP October 2015 Supplement 1, Revision 1 3-6-_ Table S3-3 Axial Burnup and Moderator Temperature Profiles WCAP-17400-NP October 2015 Supplement 1, Revision 1 3-7$3.3.4 Burnable Poison Design See Section 3.3.4 of Reference 2.While it was conservative to not credit Gadolinia as indicated in Reference 2, it is not the same for IFBA bearing fuel.[]a~ IFBA specifications are shown in Table $3-4. BPRAs are not considered in this supplement analysis.Table S3-4 IFBA Specifications Value Value Analyzed Parameter IFBA IFBA BA material ZrB 2 ZrB 2 BA '°B loading, mg/inch [ ]ac[ ]a.C BA Thickness, nils [ [ ]ac BA length, inches [ ]a'c S3.3.5 Fuel Depletion Modeling Assumptions Table S3-5 contains the fuel depletion parameters as modeled values resulting from all bounding assumptions.

See Section 3.3.5 of Reference 2 for additional fuel depletion modeling information.

Table $3-5 Additional Parameters Used in IFBA Bearing Fuel Depletion Analysis WCAP-1 7400-P Depletion IFBA Bearing Fuel Depletion Analysis Analysis Value Parameter (Analyzed in Reference

2) Value (Analyzed)

Maximum soluble boron concentration, ppm [ ],.c [ ]a.c Rated thermal power, MWt 1811 1811 Average assembly power, IVWt [ , [ ].c Core outlet moderator temperature, 0 F [ ]pc [ ].Core inlet moderator temperature, °F [ ] [ ]a,C Minimum Reactor Coolant System flow rate [(Thermal Design Flow), gpm[ ]. []c Fuel designs [ ]a'c [ ]a'c Fuel Theoretical Density, % [I ]P' [ Burnable Poison [ ]a.c [i ]a.c WCAP- 17400-NP October 2015 Supplement 1, Revision 1 3-8 S3.4 RODDED OPERATION See Section 3.4 of Reference 2.$3.5 CREDIT FOR RCCAS See Section 3.5 of Reference 2.$3.6 NORMAL CONDITION DESCRIPTION This section discusses normal conditions within the SFP besides the steady-state storage of fresh and spent assemblies.

During normal operation, the SEP has a soluble boron concentration of greater than 2400 ppm (including a 100 ppm uncertainty) and a moderator temperature

< 150 0 F. Beyond the storage of fuel assemblies, there are five major types of normal conditions covered in this analysis.$3.6.1 Type 1 Normal Conditions See Section 3.6.1 of Reference 2.$3.6.2 Type 2 Normal Conditions See Section 3.6.2 of Reference 2.S3.6.3 Type 3 Normal Conditions See Section 3.6.3 of Reference

2. [] ac$3.6.3.1 Consolidated Rod Storage Description See Section 3.6.3.1 of Reference 2 for details of the rod consolidation analysis performed in Reference 2.Rod consolidation was not analyzed for TFBA bearing fuel, and thus, IFBA bearing fuel is not allowed to be stored as Fuel Category 7, described in Section 3.7.1 of Reference 2 (See Section $3.7.1 for a description of fuel categories).

$3.6.3.2 Failed Fuel Basket Description See Section 3.6.3.2 of Reference

2. []a,c WCAP- 17400-NP October 2015 Supplement 1, Revision 1 3-9$3.6.4 Type 4 Normal Conditions See Section 3.6.4 of Reference 2.S3.6.5 Type 5 Normal Conditions See Section 3.6.5 of Reference 2.S3.7 KENO MODELING ASSUMPTIONS See Section 3.7 of Reference

2. [Ia,c S3.7.1 Array Descriptions Descriptions of the fuel storage arrays allowable for use with L7FBA bearing fuel at Prairie Island are described here. Each storage array was modeled in KENO as an infinite repeating array. Array descriptions are the same as those listed in Reference 2, with the exception that Fuel Category 7 is not present in the supplement analysis.The restrictions associated with arrays can be found in Section S$5.1I.WCAP- 17400-NP October 2015 Supplement 1, Revision 1 3-10 Array A Fuel Category 6 assembly in every cell.Array B Fuel Category 3 assembly in three of every four cells; one of every four cells is empty (water filled).Array C Checkerboard pattern of Fuel Category 1 assemblies and empty (water-filled) cells.Array D Two Fuel Category 5 assemblies, one Fuel Category 1 assembly, and one empty cell in every four cells. The Fuel Category 1 and empty cell shall be face-adjacent.

Array E Two Fuel Category 2 assemblies, one Fuel Category 4 assembly, and one empty cell in every four cells. The Fuel Category 4 assembly shall be diagonal to the empty cell.6 6 6 6 3 3 3 X 1 X X 1 X 1 2 4 x 2 Array G Nine Fuel Category 5 assemblies in every nine cells with a full length RCCA loaded in the center assembly.5 5 5 5 5 5R 51515 Notes: 1. In all arrays, an assembly of lower reactivity may replace an assembly of higher reactivity.

2. Fuel Category 1 is fuel up to 5.0 wt% 2 3 5 U; no burnup is required.3. Fuel Categories 2 through 6 are determined from the coefficients provided in Section S$5.1.4. An X indicates an empty (water-filled) cell.5. An R indicates the assembly must contain a full length RCCA.6. Attributes for each array are as stated in the definition.

Diagram is for illustrative purposes only.7. An empty (water-filled) cell may be substituted for any fuel containing cell in any storage array.Figure $3-1 Allowable Storage Arrays WCAP- 17400-NP October 2015 Supplement 1, Revision 1 3-11 Additionally, Array F, containing Fuel Category 7 is described in Section 3.7.1 of Reference 2 and was not addressed in this supplement.

As a result, consolidation of JEBA bearing fuel is not allowed.$3.8 ACCIDENT DESCRIPTION The following reactivity increasing accidents are considered in this analysis:* Mis load of one fresh fuel assembly into incorrect storage rack location* Inadvertent removal of an RCCA* SFP. temperature greater than normal operating range (150 0 F)* Dropped & misplaced fresh fuel assembly* Multiple misload of fresh fuel assemblies o[0]a,c Satisfy'ing the regulatory requirement for a Type II multiple misload ensures 10 CFR 50.68 accident requirements are met for any potential misload in the SFP possible at the Prairie Island Nuclear Generating Plant.The inputs to the accident analysis are the results of the burnup limit calculations discussed in Section$4.3.WCAP-l 17400-NP October 2015 Supplement 1, Revision 1 4-1 S4. ANALYSIS DESCRIPTION

& CALCULATIONS See Section 4 of Reference 2.$4.1 BURNUIP LIMIT GENERATION See Section 4.1 of Reference 2.[I ,o S4.1.1 Target keff Calculation Description See Section 4.1.1 of Reference 2.S4.1.2 Biases & Uncertainties Calculations Reactivity biases are known variations between the real and analyzed system and their reactivity impact is added directly to the calculated k~f. Biases include the pooi temperature and code validation biases as well as the fission product and actinide worth bias, which was changed from an uncertainty in Reference 2. Uncertainties account for allowable variations within the real model whether they are physical (manufacturing toleran~ces), analytical (depletion) or measurement related (bumup measurement uncertainty).

$4.1.2.1 Bias & Uncertainty Descriptions The following sections describe the biases and uncertainties that are accounted for in this analysis.$4.1.2.1.1 Manufacturing Tolerances

[]a~ See Section 4.1.2.1.1 of Reference 2 for additional details conceeming manufacturing tolerances.

S4.1.2.1.2 Burnup Measurement Uncertainty See Section 4.1.2.1.2 of Reference 2.$4.1.2.1.3 Depletion Uncertainty See Section 4.1.2.1.3 of Reference 2.WCAP- 17400-NP October 2015 Supplement 1, Revision 1 4-2$4.1.2.1.4 Fission Product Worth and Actinide Bias Methodology from Section 4.1.2.1.4 of Reference 2 was updated to incorporate the most recent information available concerning fission product worth (and actinide) validation.

This updated description is given here.In NUREG/CR-7 109, "An Approach for Validating Actinide and Fission Product Burnup Credit Criticality Safety Analyses-Criticality (kIr) Predictions" (Reference

4) presents findings that show for minor actinide and fission product nuclides for which adequate critical experiment data are not available, calculations of k~ff uncertainty due to nuclear data uncertainties can be used to establish a bounding bias value which was approximately 1.5% of the worth of the minor actinides and fission products for which adequate critical experiment data are not available.

[I]ac$4.1.2.1 .5 Operational Uncertainty See Section 4.1.2.1.5 of Reference 2.$4.1.2.1.6 Eccentric Fuel Assembly Positioning See Section 4.1.2.1.6 of Reference 2.$4.1.2.1.7 Other Uncertainties See Section 4.1.2.1.7 of Reference 2.$4.1.2.1.8 Pool Temperature Bias See Section 4.1.2.1.8 of Reference 2.WCAP- 17400-NP October 2015 Supplement 1, Revision 1 4-3 S4.1.2.1.9 Borated and Unborated Biases and Uncertainties Prairie Island Technical Specifications require the SFP lkf to be < 0.95 under borated conditions accounting for all applicable biases and uncertainties.[

]a~c$4.1.2.2 Storage Array Biases & Uncertainties Results See Section 4.1.2.2 of Reference 2, excluding the reference to fuel operated in cycles 1-4.WCAP- 17400-NP October 2015 Supplement 1, Revision 1 4-4$4.1.2.2.1 Storage Array Biases & Uncertainties for IFBA Bearing Fuel STable S4-1 Biases & Uncertainties for Array A LFBA Bearing FuelI]a)c a,c WCAP-17400-NP October 2015 Supplement 1, Revision 1 4-5 II m m Table $4-2 Biases & Uncertainties for Array B IFBA Bearing Fuel]a~c I a,c WCAP-1 7400-NP October 2015 Supplement 1, Revision 1 4-6 Biases and Uncertainties for Array C IiFBA Bearing fuel were not specifically calculated.

See Section$5.1 for more infonnaation on Array C (Fuel Category 1) storage.B Table $4-3 Biases & Uncertainties for Array D IFBA Bearing Fuel I a,c II]a,c WCAP- 17400-NP October 2015 Supplement 1, Revision 1 4-7 h *m UTable S4-4 Biases & Uncertainties for Array E IFBA Bearing Fuel[]a)c I a,c WCAP- 17400-NP October 2015 Supplement 1, Revision 1 4-8 H Table S4-5 Biases & Uncertainties for Array G IFBA Bearing Fuel[]EC I a,c IL] ., WCAP- 1 7400-NP October 2015 Supplement 1, Revision 1 4-9$4.1.2.2.2 Biases & Uncertainties for Fuel Operated During Cycles 1-4 IFBA bearing fuel was not operated during cycles 1-4 and no analysis is performed for fuel operated during these cycles. See Section 4.1.2.2.2 of Reference 2 for bias and uncertainty determination for Fuel Operated During Cycles 1-4.$4.1.2.3 Consolidated Rod Storage Canister Biases & Uncertainties Results 1IFBA Bearing fuel is not considered for consolidation and is therefore prohibited for storage within Array F from Section 3.7.1 of Reference 2 (i.e. there is no Category 7 IFBA bearing fuel). See Section 4.1.2.3 of Reference 2 for details of the consolidated rod storage canister analysis for Reference 2.A single interface comprising Array A and Array F was evaluated for storage with the Consolidated Rod Storage Canister.

[$4.1.2.4 Failed Fuel Basket Biases & Uncertainties See Section 4.1.2.4 of Reference

2. No new analysis was performed for the Failed Fuel Basket as fresh fuel from Reference 2 will bound IFBA bearing fresh fuel of the same enrichment and fuel type.S4.2 SOLUBLE BORON CREDIT In this analysis, boron credit calculations assume boron which is 19.4 at% '°B, because the isotopic concentration of boron can vary as low as 19.4 at% '°B.Table S4-6 presents the maximum keffvalues for normal conditions including biases and uncertainties and administrative margin at a boron concentration of 400 ppm at 19.4 at% '°B. It is demonstrated that 400 ppm at 19.4 at% '°B is sufficient to comply with the acceptance criterion of ker <0.95 under all normal conditions (see Table S4-6). Additionally, Table S4-6 data identify the limiting storage array and the soluble boron concentration required to meet a lkf _ 0.95.WCAP- 17400-NP October 2015 Supplement 1, Revision 1 4-10 h d I II Table $4-6 [IIc a c$4.3 RODDED OPERATION See Section 4.3 of Reference

2. []a,c$4.4 NORMAL CONDITIONS

$4.4.1 Type 1 Normal Conditions See Section 4.4.1 of Reference 2.S4.4.2 Type 2 Normal Conditions See Section 4.4.2 of Reference 2.$4.4.3 Type 3 Normal Conditions See Section 4.4.3 of Reference

2. Fuel consolidation is not permitted with IFBA bearing fuel, however the interface-specific analysis performed in Reference 2 for acceptability of an interface between Array A and Array F (described in Section 3.7.1 of Reference 2 ) was performed for IFBA bearing fuel within Array A and non-IFBA bearing fuel in Array F which again confirm the acceptability of an interface between Array A and Array F with IFBA bearing fuel.WCAP- 17400-NP October 2015 Supplement 1, Revision 1 4-11]a~c S4.4.4 Type 4 Normal Conditions See Section 4.4.4 of Reference 2.S4.4.5 Type 5 Normal Conditions See Section 4.4.5 of Reference 2.S4.5 ACCIDENTS S4.5.1 Assembly Misloads into the Storage Racks$4.5.1.1 Single Assembly Misload into the Storage Racks The misloaded fresh fuel accident scenario is analyzed by placing a 5.0 wt% 2 3 5 U fresh fuel assembly into the water-filled cell required in Arrays B, D, and E, and by replacing a burned fuel assembly with a 5.0 wt% 2 3 5 U fresh fuel assembly for Arrays A and G. [ ]~ hsacdn requires 890 ppm of boron to maintain l~ff less than 0.95 including biases, uncertainties and administrative margin. [a~c S4.5.1.2 Multiple Assembly Misload into the Storage Racks A multiple assembly misload is an accident scenario where assemblies are misloaded in series due to a common cause. []a~c WCAP- 1 7400-NP October 2015 Supplement 1, Revision 1 4-12$4.5.2 Inadvertent Removal of an RCCA See Section 4.5.2 of Reference 2.$4.5.3 Spent Fuel Temperature Outside Operating Range The SFP is to be operated at less than 150 0 F. However, under accident conditions this temperature could be higher. Due to the large volume of water in the SFP, boiling off of the pool water before remediation is not credible; therefore the lowest density of the water is the water density at boiling and atmospheric pressure, 0.96 gm/cm 3.Calculations are run with voiding and 890 ppm of soluble boron. To demonstrate conservatism additional cases with a moderator density of 0.75 gmn/cm 3 and 0.85 gmn/cm3 is performed.

The results for these calculations are presented in Table $4-7.$4.5.4 Dropped & Misplaced Fresh Assembly See Section 4.5.4 of Reference 2.$4.5.4.1.1 Accident Results ITable S4-7 gives the results of the limiting single assembly misload accident (890 ppm) as well as the resulting k~fs for a spent fuel pool heat up accident at the required single assembly misload soluble boron concentration, indicating the single assembly misload bounds the SFP heat up accident.-fj Table $4-7 [Sl.,c U a,c Additionally, Type I and Type II multiple misload accidents were evaluated.

The results of this evaluation indicate that 1380 ppm soluble boron is required to mitigate a Type I multiple misload and 2030 ppm Isoluble boron is required to mitigate a Type II multiple misload, leaving significant margin (in terms of soluble boron) to the proposed Technical Specification limit (including 100 ppm of uncertainty) of 2400 ppm soluble boron.2[ ]TC WCAP- 17400-NP October 2015 Supplement 1, Revision 1 5-1 S5. ANALYSIS RESULTS This section documents the results of the Prairie Island supplemental IFBA bearing fuel criticality safety analysis.

Included in this section are the burnup requirements for the fuel storage arrays documented in this analysis in Section $3.7.1. This section also contains the restrictions placed on the various storage arrays such as placement of non-fuel items and an evaluation of normal SFP activities which are bounded by this analysis.S5.1 BURNUP LIMITS & RESTRICTIONS ON STORAGE ARRAYS Assembly storage is controlled through the storage arrays defined in Section $3.7.1. An array can only be populated by assemblies of the fuel category defined in the array definition or a lower reactivity array.Fuel categories are defined by assembly bumup, enrichment and decay time as provided by Table $5-2 through Table $5-11, with the exception of Fuel Category 1 assemblies.

Fuel Category 1 assemblies are defined in the notes to Table $5-1. Fuel Category 7 from Reference 2 (consolidated rod storage) is not permitted with IIFBA bearing fuel.Table $5-1 Fuel Categories Ranked by Reactivity Fuel Category 1 High Reactivity Fuel Category 2 Fuel Category 3 Fuel Category 4 Fuel Category 5 Fuel Category 6 Low Reactivity Notes: 1. Fuel categories are ranked in order of decreasing reactivity, e.g., Fuel Category 2 is less reactive than Fuel Category 1, etc.2. Fuel Category 1 is fuel up to 5.0 wt% 2 3 5 TU; no burnup is required.3. Fuel Categories 2 through 6 are determined from the coefficients provided.]a,c WCAP- 17400-N-P Supplement 1, Revision 1 5-2$5.1.1 Requirements for IFBA Bearing Fuel Table S5-2 Fuel Category 2 Burnup Requirement Coefficients Coefficients Decay Time II (yr) A 1 A 2 A 3 A 4 0 -1.9089 22.9292 -81.9646 91.4193 Notes: 1. All relevant uncertainties are explicitly included in the criticality analysis.

For instance, no additional allowance for bumup uncertainty or enrichment uncertainty is required.

For a fuel assembly to meet the requirements of a Fuel Category, the assembly burnup must exceed the "minimum bumnup" (GWdiMTU)given by the curve fit for the assembly "decay time" and "initial enrichment." The specific minimum burnup required for each fuel assembly is calculated from the following equation: BU=AI

En 3 + A2*En 2+/-+A 3 *En +A 4 2. Initial enrichment, En, is the nominal 2 3 5 U enrichment.

Any enrichment between 2.9 wt%/ 2 3 5 U and 5.0 wt%/2 3 5 U may be used.WCAP-l17400-NP October 2015 Supplement 1, Revision 1 5-3 Table $5-4 Fuel Category 3 Burnup Requirement Coefficients Coefficients Decay Time (yr) A 1 A 2 A 3 A 4 0 -0.0536 0.5516 8.2824 -23.3157 5 -0.0372 0.2803 9.0736 -23.8543 10 -0.0408 0.2587 9.0667 -23.6452 15 -0.0893 0.7485 7.2536 -2 1.4102 20 -0.1011 0.8822 6.6122 -20.4468 Notes: 1. All relevant uncertainties are explicitly included in the criticality analysis.

For instance, no additional allowance for bumup uncertain~ty or enrichment uncertainty is required.

For a fuel assembly to meet the requirements of a Fuel Category, the assembly bumup must exceed the "'minimum burnup" (GWd/MTU)given by the curve fit for the assembly "decay time" and "initial enrichment." The specific minimum burnup required for each fuel assembly is calculated from the following equation: BU-=AI

En 3 + A 2

En 2 +A 3

En +A 4 2. Initial enrichment, En, is the nominal 2 3 SU enrichment.

Any enrichment between 2.5 wt% 2 3 5 U and 5.0 wt 0/23Umay be used.3. Linear interpolation between decay times is pennitted.

However, an assembly with a decay time greater than 20 years must use the 20 years limits.Table S5-5 Fuel Category 3 Burnup Requirements (GWdIMTU)wt% Decay Time (yr) 2.50 3.40 4.00 4.50 5.00 0 0.000 9.114 15.209 20.241 25.186 5 0.000 8.774 14.544 19.263 23.871 10 0.000 8.569 14.150 18.676 23.056 15 0.000 8.395 13.865 18.251 22.408 20 0.000 8.259 13.647 17.960 22.032 Notes: 1. This table is included as an example, the burnup limits will be calculated using the coefficients provided.WCAP- 17400-NP October 2015 Supplement I, Revision 1 5-4 Table $5-6 Fuel Category 4 Burnup Requirement Coefficients Coefficients Decay Time II (yr) A 1 A 2 A 3 A 4 0 1.3659 -14.9709 63.0347 -72.9223 Notes: 1. All relevant uncertainties are explicitly included in the criticality analysis.

For instance, no additional allowance for burnup uncertainty or enrichment uncertainty is required.

For a fuel assembly to meet the requirements of a Fuel Category, the assembly bumnup must exceed the "minimum burnup" (GWd/MTU)given by the curve fit for the assembly "decay time" and "initial enrichment." The specific minimum burnup required for each fuel assembly is calculated from the following equation: BU=AI

En 3 +A 2 *En 2 + A 3 *En+ An 2. Initial enrichment, En, is the nominal 2 3 5 U enrichment.

Any enrichment between 1.8 wt% 2 3 5 U and 5.0 wt%235U may be used.Table S5-7 Fuel Category 4 Burnup Requirements (GWd/MTU)wt% Decay Time (yr) 1.80 3.40 4.00 4.50 5.00 0 0.000 22.017 27.100 32.041 38.716 Notes: 1. This table is included as an example, the burnup limits will be calculated using the coefficients provided.WCAP-17400-NP October 2015 Supplement 1, Revision 1 5-5 Table $5-8 Fuel Category 5 Burnup Requirement Coefficients Coefficients Decay Time (yr) A 1 A 2 A 3 A 4 0 0.2744 -3.7275 29.5218 -41.7174 5 0.0533 -1.3478 20.6704 -32.3235 10 -.0.0407 -0.3472 16.7092 -27.9591 15 -0.1809 1.0636 11.8632 -23.0476 20 '-0.0897 0.23 12 13.9007 -24.5529 Notes: 1. All relevant uncertainties are explicitly included in the criticality analysis.

For instance, no additional allowance for bumup uncertainty or enrichment uncertainty is required.

For a fuel assembly to meet the requirements of a Fuel Category, the assembly bumup must exceed the "minimum burnup" (GWd/MTU)given by the curve fit for the assembly "decay time" and "initial enrichment." The specific minimum burnup required for each fuel assembly is calculated from the following equation: BU -A

En 3 + A 2

En 2 +A 3

En +A 4 2. Initial enrichment, En, is the nominal 235U enrichment.

Any enrichment between 1.75 wt% 2 3 5 U and 5.0 wt%23Umay be used.3. Linear interpolation between decay times is permitted.

However, an assembly with a decay time greater than 20 years must use the 20 years limits.Table $5-9 Fuel Category 5 Burnup Requirements (GWd/MTU)wt% 72Su Decay Time (yr) 1.75 3.40 4.00 4.50 5.00 0 0.000 26.352 34.291 40.654 47.004 5 0.000 24.470 32.205 38.257 43.996 10 0.000 23.239 30.718 36.493 41.819 15 0.000 22.472 29.845 35.390 40.246 20 0.000 21.857 29.008 34.508 39.518 Notes: 1. This table is included as an example, the burnup limits will be calculated using the coefficients provided.WCAP- 17400-NP October 2015 Supplement 1, Revision 1 5-6 Table $5-10 Fuel Category 6 Burnup Requirement Coefficients Coefficients Decay Time (yr) A 1 A 2 A 3 A 4 0 0.4604 -5.9192 38.3216 -50.3021 5 0.4161 -5.2825 34.6238 -45.6381 10 0.3716 -4.7154 31.7812 -42.2260 15 0.1816 -2.7038 24.7285 -35.1164 20 0.1318 -2.1711 22.5833 -32.7644 Notes: 1. All relevant uncertainties are explicitly included in the criticality analysis.

For instance, no additional allowance for burnup uncertainty or enrichment uncertainty is required.

For a fuel assembly to meet the requirements of a Fuel Category, the assembly bumup must exceed the "minimum bumup" (GWd/MTU)given by the curve fit for the assembly "decay time" and "initial enrichment." The specific minimum burnup required for each fuel assembly is calculated from the following equation: BU-=A1 *En 3 +A 2 *En 2 +A 3 *En +A 4 2. Initial enrichment, En, is the nominal 2 3 5 U enrichment.

Any enrichment between 1.7 wt% 235U and 5.0 wt 0/be used.3. Linear interpolation between decay times is permitted.

However, an assembly with a decay time greater than 20 years must use the 20 years limits.Table $5-11 Fuel Category 6 Burnup Requirements (GWd/MTU)wt% 23SU Decay Time (yr) 1.70 3.40 4.00 4.50 5.00 0 0.000 29.661 37.743 44.235 50.876 5 0.000 27.372 34.968 41.115 47.431 10 0.000 25.925 33.235 39.165 45.245 15 0.000 24.842 32.159 37.958 43.631 20 0.000 24.101 31.266 36.906 42.350 Notes: 1. This table is included as an example, the burnup limits will be calculated using the coefficients provided.WCAP-1 7400-NP October 2015 Supplement 1, Revision 1 5-7$5.1.2 Burnup Requirements for Fuel Operated during Cycles 1-4 IiFBA bearing fuel was not present in Cycles 1-4 and no analysis is performed.

The results of Section 5.1.2 of Reference 2 remain valid for fuel operated in Cycles 1-4.$5.1.3 Decay Time Interpolation See Section 5.1.3 of Reference 2.$5.2 RODDED OPERATION Prairie Island has experienced load follow operation in the past as described in Section 4.3 of Reference 2.[S5.3 INTERFACE CONDITIONS See Section 5.3 of Reference 2.S5.4 NORMAL CONDITIONS See Section 5.4 of Reference 2.$5.4.1 Type 1 Normal Conditions See Section 5.4.1 of Reference 2.S5.4.2 Type 2 Normal Conditions See Section 5.4.2 of Reference 2.$5.4.3 Type 3 Normal Conditions See Section 5.4.3 of Reference

2. Consolidation is not permitted for IFBA bearing fuel, i.e., Array F, Fuel Category 7 fuel from Reference 2 is not a valid storage array for IFBA bearing fuel.$5.4.4 Type 4 Normal Conditions See Section 5.4.4 of Reference 2.WCAP- 1 7400-NP October 2015 Supplement 1, Revision 1 5-8$5.4.5 Type 5 Normal Conditions See Section 5.4.5 of Reference 2.S5.5 SOLUBLE BORON CREDIT Soluble boron is credited in the Prairie Island SEP to keep kdrS< 0.95 under all normal and credible accident scenarios.

Under normal conditions, the requirement is 400 ppm of soluble boron. Under accident conditions including a full pool misload of fresh fuel, 2030 ppm of soluble boron is required to ensure ken-< 0.95 which leaves significant margin to the proposed Technical Specification value of 2500 ppm (analysis assumes 2400 ppm maximum with an inclusion of 100 ppm uncertainty).

WCAP- 17400-NP October 2015 Supplement 1, Revision 1 6-1 S6. COMPARISON WITH "FUEL NOT OPERATED IN CYCLES 1-4" BUIRNUP LIMITS Both this supplemental report and Reference 2 contain identical storage array descriptions, for which bumup limits are determined for six fuel categories.

The design difference between the two analyses is the presence oflIFBA within the fuel during depletion in this supplemental analysis.

[]a,c These storage arrays (A, B, C, D, E and G) are seen in Section S3.7.l, with fuel category descriptions (1 through 6) in Section S2.2. Storage Array F, containing Fuel Category 7 from Reference 2 is not evaluated for storage with IFBA bearing fuel.I o S6.1 FINAL STORAGE (BURNUP) LIMIT COMPARISON Table S6-1 through Table S6-5 provide a comparison of evaluated burnup limits at the maximum allowable, fresh fuel enrichment and enrichments of 3.4, 4.0, 4.5 and 5.0 wt% 2 3 5U for fuel categories 2, 3, 4, 5 and 6 respectively.

Reactivity calculations associated with Array C were not performed.

[]ac This supplement analysis does not address Fuel Category 7.WCAP-1 7400-NP October 2015 Supplement 1, Revision 1 6-2 Table $6-1 Fuel Category 2 Burnup Requirements Comparison (GWd/MTUJ), wt% 2 3 5 U Fuel Group Decay Time ________ ____ ____(yr) 2.90 3.40 4.00 4.50 5.00 IFBA Bearing Fuel 0.000 2.774 8.258 12.946 16.214 Notes: 1. This table is included for comparison purposes, the burmup limits will be calculated using the coefficients from the respective burnup coefficients.

Table $6-2 Fuel Category 3 Burnnp Requirements Comparison (GWdIMTU)wt% 2 3 5 U Fuel Group Decay Time (yr) 2.50 3.40 4.00 4.50 5.00 Fuel Not Operated in Cycles 1-4 0.000 8.567 14.379 19.152 23.765 0 IFBA Bearing Fuel 0.000 9.114 15.209 20.241 25.186 Fuel Not Operated in Cycles 1-4 0.000 8.199 13.767 18.285 22.559 5 IFBA Bearing Fuel 0.000 8.774 14.544 19.263 23.87 1 Fuel Not Operated in Cycles 1-4 0.000 8.044 13.489 17.837 2 1.837 10 IFRA Bearing Fuel 0.000 8.569 14.150 18.676 23.056 Fuel Not Operated in Cycles 1-4 0.000 7.865 13.259 17.537 21.392 15 IFBA Bearing Fuel 0.000 8.395 13.865 18.251 22.408 Fuel Not Operated in Cycles 1-4 0.000 7.710 13.091 17.281 20.882 20 IFBA Bearing Fuel 0.000 8.259 13.647 17.960 22.032 Notes: 1. This table is included as an example, the bumnup limits will be calculated using the coefficients from the respective burnup coefficients.

WCAP-1 7400-NP October 2015 Supplement 1, Revision 1 6-3 Table S6-.3 Fuel Category 4 Burnup Requirements Comparison (GWdIMTU)wt% 2 3 5 U SFuel Group Decay Time (yr) 1.80 3.40 4.00 4.50 5.00 Fuel Not Operated in Cycles 1-4 0.000 22.013 27.100 32.031 38.676 0 IFBA Bearing Fuel 0.000 22.017 27.100 32.041 38.716 Notes: 1. This table is included for comparison purposes, the burnup limits will be calculated using the coefficients from the respective burnup coefficients.

Table $6-4 Fuel Category 5 Burnup Requirements Comparison (GWd/MTU)wt%/ 2 3 5 U Fuel Group Decay Time (yr) 1.75 3.40 4.00 4.50 5.00 Fuel Not Operated in Cycles 1-4 0.000 24.741 3 1.906 37.991 44.636 IFBA Bearing Fuel 0.000 26.352 34.291 40.654 47.004 Fuel Not Operated in Cycles 1-4 0.000 23.230 30.284 36.052 4 1.961 IFBA Bearing Fuel 0.000 24.470 32.205 38.257 43.996 Fuel Not Operated in Cycles 1-4 0.000 22.116 28.988 34.467 39.841 10 IFBA Bearing Fuel 0.000 23.239 30.718 36.493 41.819 Fuel Not Operated in Cycles 1-4 0.000 21.108 27.867 32.827 37.017 15 IFBA Bearing Fuel 0.000 22.472 29.845 35.390 40.246 Fuel Not Operated in Cycles 1-4 0.000 20.564 27.390 32.167 35.773 20 IFBA Bearing Fuel 0.000 21.857 29.008 34.508 39.5 18 Notes: 1. This table is included as an example, the burnup limits will be calculated using the coefficients from the respective burnup coefficients.

WCAP- 17400-NP October 2015 Supplement 1, Revision 1 6-4 Table S6-5 Fuel Category 6 Burnup Requirements Comparison (GWd/MTU)wt% 2 3 Su Fuel Group Decay Time (yr) 1.70 3.40 4.00 4.50 5.00 Fuel Not Operated in Cycles 1-4 0.000 26.794 34.808 41.785 49.486 IFBA Bearing Fuel 0.000 29.66 1 37.743 44.235 50.876 Fuel Not Operated in Cycles 1-4 0.000 24.886 31.846 38.341 46.207 IFBA Bearing Fuel 0.000 27.372 34.968 41.115 47.431 Fuel Not Operated in Cycles 1-4 0.000 24.194 30.847 36.760 43.591 10 IFBA Bearing Fuel 0.000 25.925 33.235 39.165 45.245 Fuel Not Operated in Cycles 1-4 0.000 23.279 30.260 36.114 42.275 15 IFBA Bearing Fuel 0.000 24.842 32.159 37.958 43.631 Fuel Not Operated in Cycles 1-4 0.000 22.705 29.593 35.320 41.262 20 IFBA Bearing Fuel 0.000 24.101 3 1.266 36.906 42.350 Notes: 1. This table is included as an example, the burnup limits will be calculated using the coefficients from the respective burnup coefficients.

As can be seen in Table $6-1 through Table S6-5, all burnup limits for IFBA bearing fuel are greater in burnup comparing to Fuel Not Operated in Cycles 1-4 bumup limits. Additionally, all maximum fresh fuel enrichments are the same. This means that all derived burnup limits for JFBA bearing fuel from Table$5-2, Table $5-4, Table $5-6, Table $5-8 and Table $5-10 (shown in Section $5.1.1) will always be greater than all burnup limits developed for Fuel Not Operated in Cycles 1-4 from Reference 2.S6.2 METHODOLOGY AN'D INPUT COMPARISON S6.2.1 Methodology Comparison

]f.,$6.2.2 Input Comparison and Conclusion A comparison of depletion input for IFBA bearing fuel and "Fuel Not Operated in Cycles 1-4" analysis is given in Table $6-6. Additionally, input requirements for the misload accident are updated to incorporate a multiple misload, which increases conservatism.

Usage of isotopics which result in a harder spectrum (IFBA bearing fuel) is conservative over WCAP-17400 isotopics for a misload since boron worth will be reduced for harder spectrum systems.WCAP- 17400-NP October 2015 Supplement 1, Revision 1 6-5 ITable $6-6 Comparison of Input Core Operational Parameters During Depletion The data in Table S6-6 show that aside from the addition of IFBA to the 422V+ fuel, the soluble boron concentration, fuel pellet theoretical density and axial burnup profile input changed during depletion.

a_,c]a.c 1[I, WCAP- 17400-NP October 2015 Supplement 1, Revision 1 6-6 S6.2.3 Accidents and Soluble Boron Credit Review Table $6-7 summarizes the soluble boron requirements for different scenarios for the IFBA bearing fuel supplement analysis and for "Fuel Not Operated in Cycles 1-4".Table S6-7 Soluble Boron Credit IFBA Bearing Fuel Fuel Not Operated in Cycles 1-4 Comparison (ppmn) (ppm)Normal Operations 2 340 3593 Single Misload 890 910 Multiple Misload (Type I) 1380 N/A Multiple Misload (Type II) 2030 N/A Tech. Spec. Limit 24004 1800 Note: All soluble boron concentrations are based on 19.4 at% X°Table $6-7 data indicate that less soluble boron is required for Fuel Not Operated in Cycles 1-4 for analogous scenarios.

Less finely spaced checks were performed for the soluble boron credit calculations supporting Reference 2, contributing to small differences.

The addition of the multiple misload accidents and the increased technical specification limit ensure that if 400 ppm of soluble boron is credited for normal operation and 2030 ppm of soluble boron for accident conditions, IFBA bearing fuel burnup limit coefficients can be appropriately used for Fuel Not Operated in Cycles 1-4. The 2030 ppm of soluble boron determined for multiple misloads [$6.2.4 Comparison Conclusions All burnup limits associated with IFBA bearing fuel increased (0 to 4 GWd/MTU maximum) compared to the corresponding bumup limits for Fuel Not Operated in Cycles 1-4 from Reference

2. The maximum increase in bumup requirements is a 3.745 GWd/MTU for Category 5 fuel with 20 years decay time, while most increases are less than -1.5 GWd/MTU. The only methodology change made (fission product and minor actinide worth treatment) is conservative.

Input requirements for the misload accident are updated to incorporate a multiple misload, which increases conservatism.

Usage of isotopics which result in a harder spectrum (IFBA bearing fuel) is conservative over WCAP-1 7400 isotopics for a misload since boron worth will be reduced for harder spectrum systems. Results from soluble boron credit analysis, when utilizing 400 ppm 19.4 at% '0 B for normal operations and 2030 ppm 19.4 at% '0 B for accident conditions are shown to be bounding for both WFBA bearing fuel and Fuel Not Operated in Cycles 1-4 from Reference

2. The lone interface condition analyzed was shown to be acceptable for IFBA-bearing fuel in this report and for Fuel Not Operated in Cycles 1-4 in Reference 2 and the normal conditions evaluated in Reference 2 were not impacted.

As a result of these findings, it is conservative to utilize IFBA bearing fuel burnup limit coefficients for all fuel storage beyond fuel operated in cycles 1-4 for Prairie Island.2Bt credit 400 ppm soluble boron. 340 ppm was not explicitly checked for Fuel Not Operated in Cycles 1-4.3350 ppm soluble boron determined in Reference 2 atl9.9 at% '°B corresponds to 359 ppm at 19.4 at% 1 OB.4 Based on a Proposed Tech. Spec. limit of 2500 ppm with 100 ppm uncertainty.

WCAP- 17400-NP October 2015 Supplement 1, Revision 1 7-1 S7. REFERENCES

1. "Prairie Island Nuclear Generating Plant, Units 1 and 2 -Issuance of Amendments re: Spent Fuel Pool Criticality Changes," ML13241A383, August 2013.2. "Prairie Island Units 1 and 2 Spent Fuel Pool Criticality Safety Analysis," WCAP-17400-P, Westinghouse Electric Company LLC, July 2011.3. K. Wood, "°Draft Staff Guidance Regarding the Nuclear Criticality Safety Analysis for Spent Fuel Pools," DSS-ISG-201 0-1, Accession Number ML102220567, Nuclear Regulatory Commission, Rockville, MID, August 2010.4. J. M. Scaglione, et al., "An Approach for Validating Actinide and Fission Product Burnup Credit Criticality Safety Analyses-Criticality (kdff) Predictions," NUJREG/CR-7 109, Oak Ridge National Laboratory, Oak Ridge, TN, April 2012.WCAP-1 7400-NP October 2015 Supplement 1, Revision 1 A-i APPENDIX A VALIDATION OF SCALE 5.1 See Reference 2, Appendix A for the Validation of SCALE 5.1.WCAP- 17400-NP October 2015 Supplement 1, Revision I L-PI-1 5-087 NSPM Enclosure 5 Enclosure 5 Westinghouse WCAP-1 7400-NP Supplement 1 Revision 1 Prairie Island Units I and 2 Spent Fuel Pool Criticality Analysis Supplemental Analysis for the Storage of IFBA Bearing Fuel Non-Proprietary October 2015 Errata:* Page 4-12 provides a reference to the Technical Specification minimum boron concentration that requires clarification.

This text on page 4-12 suggests that the proposed Technical Specification limit (with uncertainty) is 2400 ppm. In fact, the proposed TS limit (as shown in Enclosure

2) is 2500 ppm.52 pages follow Westinghouse Non-Proprietary Class 3 WCAP-1 7400-NP October 2C Supplement 1, Revision 1 Prairie Island Units 1 and 2 Spent Fuel Pool Criticality Safety Analysis Supplemental Analysis for the Storage of IFBA Bearing Fuel Westinghouse

)1 5 WESTINGHOUSE NON-PROPRIETARY CLASS 3 WCAP-17400-NP Supplement 1, Revision 1 Prairie Island Units 1 and 2 Spent Fuel Pool Criticality Safety Analysis Supplemental Analysis for the Storage of IFBA Bearing Fuel Michael T. Wenner*Core Engineering

& Software Development October 2015 Reviewer:

Mykola Boychenko*

Core Engineering

& Software Development Approved:

Edmond J. Mercier*, Manager Core Engineering

& Software Development

Electroniically approved records are authenticated in the electronic document management system.Westinghouse Electric Company LLC 1000 Westinghouse Drive Cranberry Township, PA 16066, USA© 2015 Westinghouse Electric Company LLC All Rights Reserved ii REVISION HISTORY Revision Description and Impact of the Change Date 0-A Original Draft Issue 09/2015 0 Original Issue 10/20 15 1 Revision 1 to correct the normal operations Fuel Not Operating in Cycles 10/2015 1-4 soluble boron concentration from Table S$6-7. Other minor editorial updates included.TRADEMARK NOTICE Optimized ZIRLOTM and ZIRLO are trademarks or registered trademarks of Westinghouse Electric Company LLC, its affiliates and/or its subsidiaries in the United States of America and may be registered in other countries throughout the world. All rights reserved.