ML17279A124
ML17279A124 | |
Person / Time | |
---|---|
Site: | Prairie Island ![]() |
Issue date: | 09/30/2017 |
From: | Wenner M T Westinghouse |
To: | Office of Nuclear Reactor Regulation |
Shared Package | |
ML17279A095 | List: |
References | |
CAC MF7121, CAC MF7122, L-PI-17-041 WCAP-17400-NP, Sup. 1, Rev. 2 | |
Download: ML17279A124 (64) | |
Text
L-Pl-17-041 Enclosure 5 ENCLOSURE 5 WESTINGHOUSE WCAP-17400-NP SUPPLEMENT 1 REVISION 2 NSPM PRAIRIE ISLAND UNITS 1 AND 2 SPENT FUEL POQL CRITICALITY SAFETY ANALYSIS I . , . SUPPLEMENTAL ANALYSIS INCLUDING THE STORAGE OF IFBA BEARING FUEL NON-PROPRIETARY
- . SEPTEMBER 2017 63 pages follow
' \ Westinghouse Non-Proprietary Class 3 WCAP-17400-NP Supplement 1, Revision 2 September 2017 Prairie Island Units 1 and 2 Spent Fuel Pool Criticality Safety Analysis Supplemental Analysis Including the Storage of IFBA .* . Bearing Fuel r \ . (9 Westinghouse WESTINGHOUSE NON-PROPRIETARY CLASS 3 WCAP-17400-NP I Supplement 1, Revision 2 Prairie Island Units 1 and 2 Spent Fuel Pool Criticality Safety Analysis Supplemental Analysis Including the Storage of IFBA Bearing Fuel Michael T. Wenner* Core Engineering
& Software Development , September 2017 Reviewer:
Andrew J. Blanco* Core Engineering
& Software Development Approved:
Naomi E. Marshall*, Manager Core Engineering
& Software Development
- Electronically approved records are authenticated in the electronic document management system. Westinghouse Electric Company LLC 1000 Westinghouse Drive Cranberry Township, PA 16066, USA © 2017 Westinghouse Electric Company LLC All Rights Reserved WESTINGHOUSE NON-PROPRIETARY CLASS .3 ii REVISION HISTORY Revision Description and Impact of the Change Date 0-A Original Draft Issue 09/2015 0 Original Issue 10/2015 I Revision 1 to correct the normal operations Fuel Not Operating in Cycles 10/2015 1-4 soluble boron concentration from Table S6-7. Other minor editorial updates included.
2 Revision 2 supports a major update to the analysis.
This update 09/17 incorporates design basis input changes for IFBA Bearing fuel and incorporates grid growth and a change in eccentric positioning methodology as requested by the NRC. Additionally, WCAP-17400 limits are updated to consider the impact of the grid growth and eccentric positioning methodology change. Final storage coefficients are taken from a conservative combination ofIFBA Bearing and updated WCAP-17400 determined storage limits. TRADEMARK NOTICE Optimized ZIRLOŽ 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 September 2017 Supplement 1, Revision 2 WESTINGHOUSE NON-PROPRIETARY CLASS 3 iii TABLE OF CONTENTS LIST OF TABLES ........................................................................................................................................
v LIST OF FIGURES ....................................................................................................................................
vii LIST OF ACRONYMS, INITIALISMS, AND TRADEMARKS
.............................................................
viii Sl. INTRODUCTION
........................................................................................................................
1-1 S2. OVERVIEW .................................................................................................................................
2-1 S2.1 ACC.EPTANCE CRITERIA ............................................................................................
2-1 S2.2 DESIGN APPROACH .....................................................................................................
2-1 S2.3 COMPUTER CODES ......................................................................................................
2-2 S2.3.l Two-Dimensional Transport Code PARAGON ...............................................
2-2 S2.3.2 SCALE Code Package .....................................................................................
2-2 S3. ANALYSIS INPUT SELECTION
................................................................................................
3-1 S3.l FUELASSEMBLYINFORMATION
..............................................................................
3-1 S3.1.1 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
.........................................................
3-3 S3.3.l S3.3.2 S3.3.3 Fuel Isotopic Generation
.................................................................................
3-3 Reactor Operation Parameters
.............
- ............................................................
3-3 Axial Profile Selection
.....................................................................................
3-4 S3.3.4 Burnable Poison Design ..................................................................................
3-6 S3.3.5 Fuel Depletion Modeling Assumptions
...........................................................
3-6 S3.4 RODDED OPERATION
..................................................................................................
3-7 S3.5 CREDIT FOR RCCAS ....................................................................................................
3-7 S3.6 NORMAL CONDITION DESCRIPTION
......................................................................
3-7 S3.6.1 Type 1 Normal Conditions
...... : .......................................................................
3-7 S3.6.2 Type 2 Normal Conditions
..............................................................................
3-7 S3.6.3 Type 3 Normal Conditions
..............................................................................
3-8 S3.6.4 Type 4 Normal Conditions
..............................................................................
3-8 S3.6.5 Type 5 Normal Conditions
..... ........................................................................
3-8 S3.7 KENO MODELING ASSUMPTIONS
............................................................................
3-8 S3.7.1 Array Descriptions
...........................................................................................
3-8 S3.8 ACCIDENT DESCRIPTION
........................................................................................
S4. ANALYSIS DESCRIPTION
& CALCULATIONS
.....................................................................
4-1 S4.1 BURNUP REQUIREMENT GENERATION
..................................................................
4-1 S4. l. l Target ketI Calculation Description
.................................................................
.4-1 S4.1.2 Biases & Uncertainties Calculations
..............................................................
.4-1 S4.2 SOLUBLE BORON CREDIT .......................................................................................
4-13 S4.3 RODDED OPERATION
................................................................................................
4-14 S4.4 NORMAL CONDITIONS
.............................................................................................
4-14 S4.4.1 Type 1 Normal Conditions
...........................................................................
.4-14 S4.4.2 Type 2 Normal Conditions
...........................................................................
.4-14 S4.4.3 Type 3 Normal Conditions
....................
- ......................................................
.4-14 WCAP-17400-NP September 2017 Supplement 1, Revision 2 WESTINGHOUSE NON-PROPRIETARY CLASS 3 iv S4.4.4 Type 4 Normal Conditions
.................
- .........................................................
.4-1 S S4.4.S Type S Normal Conditions
...........................................................................
.4-lS S4.S ACCIDENTS
.................................................................................................................
4-lS S4.S .1 Assembly Mis loads into the Storage Racks .................................................
.4-1 S S4.S.2 Inadvertent Removal of an RCCA ................................................................
.4-16 S4.S.3 Spent Fuel Temperature Outside Operating Range ......................................
.4-16
- S4.S.4 Dropped & Misplaced Fresh Assembly ........................................................
.4-16 SS. ANALYSIS RESULTS .................................................................................................................
S-1 SS.I
- BURNUPREQUIREMENTS
& RESTRICTIONS ON STORAGEARRAYS
..............
S-1 SS.1.1 Requirements for IFBA Bearing Fuel... ...........................................................
S-2 SS.1.2 Burnup Requirements for Fuel Operated during Cycles 1-4 ...........................
S-7 SS.1.3 Decay Time Interpolation
................................................................................
S-7 SS.2 RODDED OPERATION
..................................................................................................
S-7 SS.3 INTERFACE CONDITIONS
............
- .............................................................................
S-7 SS.4 NORMAL CONDITIONS
...............................................................................................
S-7 SS.4.1 Type 1 Normal Conditions
..............................................................................
S-7 SS.4.2 Type 2 Normal Conditions
..............................................................................
S-7 SS.4.3 Type 3 Normal Conditions
..............................................................................
S-7 SS.4.4 Type 4 Normal Conditions
..............................................................................
S-7 SS.4.S Type S Normal Conditions
..............................................................................
S-8 SS.S SOLUBLE BORON CREDIT .................................
- .......................................................
S-8 S6. BURNUP REQUIREMENTS FOR ALL FUEL NOT OPERATED IN CYCLES 1-4 INCLUDING IFBA BEARING FUEL .........................................................................................
6-1 S6. l IMPACT OF ECCENTRIC POSITIONING AND ASSEMBLY ENVELOPE EXPANSION BIAS METHODOLOGY CHANGE TO REFERENCE 2 BURNUP REQUIREMENTS
...........................................................................................................
6-1 S6.1.1 Updated Eccentric Positioning Methodology Reference 2 Reactivity Impact 6-1 S6. l .2 Assembly Envelope Expansion Bias Quantification for Fuel Not Operated in Cycles 1-4 fro1n Reference 2 ...........................................................................
6-2 S6.1.3 Final Combined Storage (Burnup) Requirements
...........................................
6-3 S6.2 COMPARISON OF CALCULATED BURNUP REQUIREMENTS AND FINAL COMBINED BURNUP REQUIRMENTS
......................................................................
6-8 S6.3 METHODOLOGY AND INPUT COMPARISON
........................................................
6-11 S6.3 .1 Methodology Comparison
.... : ........................................................................
6-11 S6.3.2 Input Comparison and Conclusion
................................................................
6-12 S6.3.3 Accidents and Soluble Boron Credit Review ..............
- .................................
6-13 S6.3.4 Comparison Conclusions
...............................................................................
6-13 S7. REFERENCES
.............................................................................................................................
7-1 APPENDIX A VALIDATION OF SCALE S.1 .......................................................................................
A-1 WCAP-17400-NP September 2017 Supplement 1, Revision 2 WESTINGHOUSE NON-PROPRIETARY CLASS 3 v LIST OF TABLES Table 82-1 Fuel Categories Ranked by Reactivity
........................ ...........................................................
2-1 Table 83-1 422V+ Fuel Assembly 8pecifications
.....................................................................................
3-2 Table S3-2 Design Basis Fuel Assembly Design Specifications
....................... ........................................
3-3 Table S3-3 Axial Burnup and Moderator Temperature Profiles .................................................................
3-5 Table S3-5 Additional Parameters Used in IFBA Bearing Fuel Depletion Analysis .................................
3-7 Table 84-1 Biases & Uncertainties for Array A IFBA Bearing Fuel... .....................................................
.4-8 Table S4-2 Biases & Uncerta,inties for Array B IFBA Bearing Fuel .......................................................
.4-9 Table S4-3 Biases & Uncertainties for Array D IFBA Bearing Fuel .....................................................
.4-10 Table S4-4 Biases & Uncertainties for Array E IFBA Bearing Fuel... ...................................................
.4-11 Table S4-5 Bi.ases & Uncertainties for Array G IFBA Bearing Fuel ***********************:*****************************.4-12 Table S4-6 Results For Normal Operations with 400 ppm ......................................................................
4-14 Table S4-7 Results of the Single Assembly Mis load Calculations at 890 ppm ......................................
.4-16 Table 1 Fuel Categories Ranked by Reactivity
...................................................................................
5-1 Table S5-2 Fuel Category 2 Burnup Requirement Coefficients
...............................................................
5-2 Table S5-3 Fuel Category 2 Burnup Requirements (GWd/MTU)
...........................................................
5-2 Table S5-4 Fuel Category 3 Burnup Requirement Coefficients
...............................................................
5-3 Table S5-5 Fuel Category 3 Burnup Requirements (GWd/MTU)
...........................................................
5-3 Table 85-6 Fuel Category 4 Burnup Requirement Coefficients
......................... , .....................................
5-4 Table 85-7 Fuel Category 4 Burnup Requirements (GWd/MTU)
...........................................................
5-4 Table S5-8 Fuel Category 5 Burnup Requirement Coefficients
...............................................................
5-5 Table S5-9 Fuel Category 5 Burnup Requirements (GWd/MTU)
...........................................................
5-5 Table S5-10 Fuel Category 6 Burnup Requirement Coefficients
.............................................................
5-6 Table S5-11 Fuel Category 6 Burnup Requirements (GWd/MTU)
..........................................................
5-6 Table S6-1 Eccentric Positioning Bias Worth
...................................................................................
6-2 Table S6-2 Assembly Envelope Expansion Bias Worth for Reference 2 ..........................................
6-2 Table S6-3 Fuel Category 2 Burnup Requirement Coefficients
................... ...........................................
6-3 Table S6-4 Fuel Category 2 Burnup Requirements (GWd/MTU)
..........................*................................
6-3 Table S6-5 Fuel Category 3 Burnup Requirement Coefficients
............................................ ..................
6-4 Table S6-6 Fuel Category 3 Burnup Requirements (GWd/MTU)
...........................................................
6-4 WCAP-17400-NP September 2017 Supplement 1, Revision 2 WESTINGHOUSE NON-PROPRIETARY CLASS 3 Vl Table S6-7 Fuel Category 4 Burnup Requirement Coefficients
...............................................................
6-5 Table S6-8 Fuel Category 4 Burnup Requirements (GWd/MTU)
.. : ...... , .................................................
6-5 Table S6-9 Fuel Category 5 Burn up Requirement Coefficients
..............................
.........................
6-6_ Table S6-10 Fuel Category 5 Burnup Requirements (GWd/MTU)
.........................................................
6-6 Table S6-11 Fuel Category 6 Burnup Requirement Coefficients
.............................................................
6-7 Table S6-12 Fuel Category 6 Burnup Requirements (GWd/MTU)
.........................................................
6-7 Table S6-l3 Fuel Category 2 Burnup Requirements Comparison (GWd/MTU)
.........................
- .. , ........ 6-8 Table S6-14 Fuel Category 3 Burnup Requirements Comparison (GWd/MTU)
.....................................
6-9 Table S6-15 Fuel Category 4 Burnup Requirements Comparison (GWd/MTU)
.....................................
6-9 Table S6-16 Fuel Category 5 Burnup Requirements Comparison (GWd/MTU)
...................................
6-10 Table S6-17 Fuel Category 6 Burnup Requirements Comparison (GWd/MTU)
...................................
6-11 Table S6-18 Comparison oflnput Core Operational Parameters During Depletion
...............................
6-12 Table S6-19 Soluble Boron Credit Comparison
......................................................................................
6-13 WCAP-17400-NP September 2017 Supplement 1, Revision 2 WESTINGHOUSE NON-PROPRIETARY CLASS 3 Vil LIST OF FIGURES Figure S3-1 Allowable Storage Arrays ......................................................................................................
3-9 Figure 1 Allowable Storage Arrays Reference 2 Eccentric Positioning Modeling Schematic (a) Fuel Assemblies Together (b) Fuel Assemblies Apart ............................................................
.4-3 Figure S4-2 Updated IFBA Bearing Fuel Eccentric Positioning Modeling Schematic (a) Fuel Assemblies Together (b) Fuel Assemblies Apart ........................................................................... , .... .4-4 Figure S4-3 Updated IFBA Bearing Fuel Eccentric Positioning Modeling Schematic Illustrating the Array G "Out" Eccentric Positioning Model .............. , ....................................................
.4-4 WCAP-17400-NP September 2017 Supplement 1, Revision 2 422V+ at% BA BPRA EPU gpm GT GWd ID IFBA IT ketf KENO MTU MWd MWt OD pcm ppm Prairie Island psia RCCA SFP TD Westinghouse wt% yr WCAP-17400-NP WESTINGHOUSE NON-PROPRIETARY CLASS 3 viii LIST OF ACRONYMS, INITIALISMS, AND TRADEMARKS 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 thennal 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 September 2017 Supplement 1, Revision 2 WESTINGHOUSE NON-PROPRIETARY CLASS 3 1-1 Sl. INTRODUCTION The Prairie Island Spent Fuel Pool (SFP) criticality analysis, as documented in the License Amendment Issuance, U.S. Nuclear Regulatory Commission Accession Number ML13241A383 (Reference 1), supported by WCAP-17400-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 Commission.
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 pool reactivity change associated with IFBA Bearing fuel compared to non-IFBA 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 IFBA. Under equivalent operating and storage conditions, fuel which contained IFBA during depletion will bound fuel not containing IFBA during depleti.on with regard to reactivity in the SFP due to the spectral hardening that occurs when IFBA is present from increased thermal absorption.
Consequently, burnup requirements derived for fuel containing IFBA can be applied to fuel not containing IFBA provided the input parameters assumed for the IFBA Bearing fuel are also applicable to fuel being storage that does not have IFBA. For Revision 2 of this document, specific inputs are adjusted which in many cases are applicable to all fuel stored at Prairie Island. However some inputs may only be appropriate and conservative for assemblies operated in a core with assemblies containing IFBA. For simplicity all fuel of the same fuel design operated in the same conditions as fuel containing IFBA will be referred to as IFBA Bearing fuel from here onward. As a result, burnup requirements have been determined for IFBA Bearing fuel only. Then, in order to store all fuel currently stored as "Fuel Not Operated in Cycles 1-4" and IFBA Bearing fuel using one consistent set of technical specifications, the impact of grid growth and the change of eccentric positioning methodology included ih the updated IFBA Bearing fuel analysis were incorporated into the WCAP-17400-P (Reference
- 2) analysis and a second set of updated burnup requirements were generated.
The maximum burnup requirements at analyzed enrichments between these two sets ofburnup requirements were then utilized to generate conservative burnup requirement coefficients to bound all fuel at Prairie Island other than fuel which operated during Cycles 1-4. The discussions in sections 1 through 5 contain only information and analysis used to support the development of burnup requirements for IFBA Bearing fuel. This document concludes with Section 6, which documents the development of combined burnup requirements for IFBA Bearing fuel and 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 requirements associated with cycles 1-4. WCAP-17400-NP September 2017 Supplement 1, Revision 2 WESTINGHOUSE NON-PROPRIETARY CLASS 3 2-1 S2. OVERVIEW See Section 2 of Reference
- 2. The presence ofIFBA Bearing fuel does not impact the overview.
S2.1 ACCEPTANCE CRITERIA The objective of this SFP criticality safety analysis is to ensure that the pool operates within the bounds discussed here. 1. All calculations of the effective neutron multiplication factor (ketr) 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 (ketr) performed for permissible storage arrangements at a soluble boron concentration of 400 1 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 k 0 tr is less than 0.95 under all postulated accident conditions with a soluble boron concentration of less than 2400 2 ppm. This criterion shall also be met including margin for all applicable biases and uncertainties with 95% probability at a 95% confidence level. S2.2 DESIGN APPROACH Table S2-1 lists the fuel categories ranked by reactivity evaluated for IFBA Bearing fuel. Table S2-1 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% 235 U; no bumup 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 of340 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. 2 Based on a Proposed Tech. Spec. limit of2500 ppm with 100 ppm uncertainty.
WCAP-17400-NP September 2017 Supplement 1, Revision 2 WESTINGHOUSE NON-PROPRIETARY CLASS 3 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 to store 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 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.l 1\vo-Dimensional Transport Code PARAGON "See Section 2.3.1 of Reference
- 2. S2.3.1.1 PARAGON Cross-Section Library See Section 2.3.1.1 of Reference
- 2. S2.3.2 SCALE Code Package See Section 2.3.2 of Reference
- 2. S2.3.2.1 SCALE 44-Group Cross-Section Library See Section 2.3.2.1 of Reference
- 2. WCAP-17400-NP September 2017 Supplement 1, Revision 2 WESTINGHOUSE NON-PROPRIETARY CLASS 3 3-1 S3. ANALYSIS INPUT SELECTION See Section 3 of Reference
- 2. S3.l 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 14xl4 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 ZIRLO tubes including Optimized ZIRLOTM High Performance Cladding Material and other variants.
Each standard fuel rod contains a column of enriched U0 2 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 UOi-Gd 2 0 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 bumup requirements.
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 S3-l contains fuel assembly specifications of the 422V+ fuel design. WCAP-17400-NP September 2017 Supplement 1, Revision 2 WESTINGHOUSE NON-PROPRIETARY CLASS 3 3-2 Table 83-1 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 [ re Maximum enrichment, wt% 235 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 0.3659 Number of guide/instrument tubes 16 /1 Guide/instrument tube OD, inch 0.5260 I 0.4220 Guide/instrument tube ID, inch 0.4920 I 0.3740 Guide/instrument tube thickness, inch 0.0170 I 0.0240 Max IFBA Rods 120 Max IFBA Thickness, mg 10 B/inch [ ]a,c Blanket Type Fully Enriched, Annular S3.1.1 Fuel Assembly Modeling Assumptions See Section 3.1.1 of Reference
- 2. ]"*0 See Section S4.2 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 actual and modeled annular blanket details for 422V+ fuel. Note that all fuel rods except Gadolinia bearing fuel rods have annular blankets.
Because Gadolinia is conservatively excluded from depletion and reactivity calculations, al fuel rods are assumed to have annular blankets.
WCAP-17400-NP September 2017 Supplement 1, Revision 2 I I WESTINGHOUSE NON-PROPRIETARY CLASS 3 Table 83-2 Design Basis Fuel Asseiµbly Design Specifications Parameter Value (422V+) Assembly type 14x14 422 Vantage+ Rod array size 14x14 Rod pitch, inch 0.556 Grid strap tolerance 3 , inch [ ]a,e Active fuel length, inch 143.25 Blanket type Annular Annular blanket length (top/bottom), inch 6 Stack density, % TD [ ]a,e Maximum enrichment, wt% 235 U 4.95 Enrichment tolerance, wt% 235 U [ re Total number of fuel rods 179 Fuel cladding OD, inch 0.422 [ re Fuel cladding ID, inch 0.3734 [ re Fuel cladding thickness, inch 0.0243 [ re Pellet OD, inch 0.3659 [ ]a,e Annular pellet ID, inch 0.1830 [ ] a,e Number of guide/instrument tubes 16 /1 Instrument tube OD, inch 0.4220 [ ]a,e Instrument tube ID, inch 0.3740 [ re Instrument tube thickness, inch 0.0240 [ ]a,e Guide tube OD, inch 0.5260 [ ]a,e Guide tube ID, inch 0.4920 [ ]a,e Guide tube thickness, inch 0.017 [ ]a,e Max IFBA Rods 120 BA 10 B loading, mg/inch [ re BA thickness, inils [ ] a,e BA length, inch [ ] a,e WCAP-17400-NP 3-3 Value (Analyzed) 14x14 422 Vantage+ 14x14 0.556 [ re 144 Annular 6 [ ]a,e 5.0 [ ]a,e 179 0.422 [ re 0.3734 [ ]a,e 0.0243 [ ]a,e 0.3659 [ ]a,e 0.1830 16 /1 0.4220 [ ]a,e 0.3740 [ re 0.0240 [ ]a,e 0.5260 [ ]a,e 0.4920 [ ]a,e 0.017 [ ]a,e 120 '* [ re [ ]a,e [ re 4 September 2017 Supplement 1, Revision 2 WESTINGHOUSE NON-PROPRIETARY CLASS 3 3-3 S3.2 FUEL STORAGE CELL & RACK DESCRIPTION See Section 3.2 of Reference
- 2. S3.2.1 Fuel Storage Cell & Rack Modeling Assumptions See Section 3.2.1 of Reference
- 2. 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 supporting Reference 2 assumed EPU conditions such that EPU operation is bounded. The input assumptions used to develop burnup requirements for the IFBA Bearing fuel evaluated in this supplement to Reference 2 are determined based on the planned operation for IFBA Bearing fuel. When considering final depletion input, bounding nominal parameters from planned IFBA Bearing fuel operation are used. S3.3.l Fuel Isotopic Generation The methodology for generating isotopic number densities to support burnup credit in this analysis is based on in-reactor operation (predicted for 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 nominalreactor 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. 83.3.2.1 Soluble Boron Concentration See Section 3 .3 .2.1 of Reference
- 2. Increased loading associated with planned IFBA Bearing fuel design data leads to an overall increase in the cycle average soluble boron concentration since the initial hold down provided by IFBA is essentially lost early in its first cycle of operation.
As a result, for Prairie Island, the incorporation of IFBA into 422V+ fuel results in a higher cycle average soluble boron concentration from representative design data. Therefore, the soluble boron concentration selected for use in the depletion calculations is 1000 ppm to bound future operation.
WCAP-17400-NP September 2017 Supplement 1, Revision 2 WESTINGHOUSE NON-PROPRIETARY CLASS 3 3-4 S3.3.2.2 Fuel Temperature Parameters important to determining fuel temperature are power level, moderator temperature, and coolant flow rate. As a result the incorporation of IFBA does not affect the methodology for determination of fuel temperature.
See Section 3.3.2.2 of Reference 2 for additional details. S3.3.2.3 Operating History and Specific Power (Specific)
Power and loading input for depletion, maximizing specific power via [ ]"'0 are unchanged with the addition of IFBA Bearing fuel. See Section 3 .3 .2.3 of Reference 2 for additional details. 83.3.3 Axial Profile Selection See Section 3.3.3 of Reference
- 2. The axial burnup and temperature profiles that were selected for use in this analysis are shown in Table S3-3. 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. [ S3.3.3.2 Axial Moderator Temperature Profile Selection The selection of axial moderator temperature profiles uses the methodology outlined in Section 3 .3 .3 .2 of Reference
- 2. [ ] a,c The moderator profiles considered in this analysis are based on the design transition cycles to IFBA Bearing fuel. The limiting temperature profiles selected are summarized in Table S3-3. S3.3.3.3 Axial Burnup and Temperature Profiles The methods and input to the methods discussed in Sections S3.3.3. l and S3.3.3.2 are followed in selecting the limiting axial burnup and Temperature profiles to be used in this analysis.
The axial burnup and temperature profiles for each burnup bin are given in Table S3-3. WCAP-17400-NP September 2017 Supplement 1, Revision 2 WESTINGHOUSE NON-PROPRIETARY CLASS 3 Table S3-3 Axial Burnup and Moderator Temperature Profiles WCAP-17400-NP 3-5 a,c September 2017 Supplement 1, Revision 2 WESTINGHOUSE NON-PROPRIETARY CLASS 3 3-6 S3.3.4 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. IFBA burns out rapidly during operation, losing all reactivity hold down while at the same time hardening the neutron spectrum from the presence of 10 B. This leads to an increase in plutonium production, thus comparatively increasing assembly reactivity in the SFP. IFBA specifications are shown in Table S3-4. 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 10 B loading, mg/inch [ ]a,e [ re BA Thickness, mils [ re [ re BA length, inches [ re [ ]a,c 83.3.5 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.
All fuel rods are modeled as fully enriched with 6" top and bottom annular blankets with as analyzed parameter values given in Table S3-2. WCAP-17400-NP September 2017 Supplement 1, Revision 2 WESTINGHOUSE NON-PROPRIETARY CLASS 3 3-7 Table S3-5 Additional Parameters Used in IFBA Bearing Fuel Depletion Analysis WCAP-17400-P Depletion IFBA Bearing Fuel Depletion Analysis Analysis Value Value (Analyzed)
Parameter (Analyzed in Reference
- 2) Maximum soluble boron concentration, [ re [ re ppm Rated thermal power, MWt 1811 1811 Average assembly power, MWt [ ]a,e [ ]a,e Core outlet moderator temperature, °F [ re [ ]a,e Core inlet moderator temperature, °F [ re [ ]a,e Minimum Reactor Coolant System flow [ ]a,e [ ]a,e rate (Thermal Design Flow), gpm Fuel designs [ ]a,e [ re Fuel Theoretical Density,%
[ re [ re Burnable Poison [ ]a,e [ ]a,e S3.4 RODDED OPERATION See Section 3.4 of Reference
- 2. S3.5 CREDIT FOR RCCAS See Section 3.5 of Reference
- 2. S3.6 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 SFP has a soluble boron concentration of greater than 2400 ppm (including a 100 ppm uncertainty) and a moderator temperature
- '.S 150 °F. Beyond the storage of fuel assemblies, there are five major types of normal conditions covered in this analysis.
S3.6.1 Type 1 Normal Conditions See Section 3.6.1 of Reference
- 2. S3.6.2 Type 2 Normal Conditions See Section 3.6.2 of Reference
- 2. WCAP-17400-NP September 2017 Supplement 1, Revision 2 WESTINGHOUSE NON-PROPRIETARY CLASS 3 3-8 S3.6.3 Type 3 Normal Conditions See Section 3.6.3 of Reference
- 2. S3.6.3.1 Consolidated Rod Storage Description See Section 3.6.3. l of Reference 2 for details of the rod consolidation analysis performed in Reference
- 2. I* Rod consolidation was not analyzed for IFBA 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 S3. 7 .1 for a description of fuel categories).
S3.6.3.2 Failed Fuel Basket Description See Section 3.6.3.2 of Reference
- 2. S3.6.4 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. IFBA Bearing fuel was modeled as solid fuel with 6 inch fully enriched annular blankets along the axial length. No credit is taken for IFBA in fresh fuel and no residual IFBA is credited in the SFP calculations.
S3. 7 .1 Array Descriptions Descriptions of the fuel storage arrays allowable for use with IFBA Bearing fuel at Prairie Island are described here. Each storage array was modeled in KENO as an infinite repeating array. Array descriptions given are the same as those listed in Reference
- 2. The restric.tions associated with arrays can be found in Section SS.I.
September 2017 Supplement 1, Revision 2 . I
\* WESTINGHOUSE NON-PROPRIETARY CLASS 3 Array A I Fuel Category 6 assembly in every cell. ArrayB Fuel Category 3 assembly in three of every four cells; one of every four cells is empty (water filled). Array t Checkerboard pattern of Fuel Category 1 assemblies and empty (water-filled) cells. ArrayD 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.
ArrayE 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. Array G 5 Nine Fuel Category 5 assemblies in every nine cells with a full length RCCA loaded in the center assembly.
Notes: 5 5 6 6 3 3 1 x 5 x 2 x 5 SR 5 1. In all arrays, an assembly of lower reactivity may replace an assembly of higher reactivity.
- 2. 3. 4. 5. Fuel Category 1 is fuel up to 5.0 wt% 235 U; no burnup is required.
Fuel Categories 2 through 6 are determined from the coefficients provided in Section S5.1. An X indicates an empty (water-filled) cell. An R indicates the assembly must contain a full length RCCA. 6 6 3 x x 1 5 1 4 2 5 5 5 6. 7. Attributes for each array are as stated in the definition.
Diagram is for illustrative purposes only. An empty (water-filled) cell may be substituted for any fuel containing cell in any storage array. Figure S3-1 Allowable Storage Arrays 3-9 WCAP-17400-NP September 2017 Supplement 1, Revision 2 WESTINGHOUSE NON-PROPRIETARY CLASS 3 3-10 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 IFBA Bearing fuel is not allowed. 83.8 ACCIDENT DESCRIPTION The following reactivity increasing accidents are considered in this analysis:
- Misload of one fresh fuel assembly into incorrect storage rack location
- Inadvertent removal of an RCCA
- SFP temperature greater than normal operating range (150 °F) *
- Dropped & misplaced fresh fuel assembly
- Multiple mis load of fresh fuel assemblies 0 [ The inputs to the accident analysis are the results of the burnup requirement calculations discussed in Section S4.3. WCAP-17400-NP September 2017 Supplement 1, Revision 2
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.--
WESTINGHOUSE NON-PROPRIETARY CLASS 3 4-1 S4. ANALYSIS DESCRIPTION
& CALCULATIONS See Section 4 of Reference
- 2. S4.1 BURNUP REQUIREMENT GENERATION See Section 4.1 of Reference
- 2. [ S4.1.1 Target kerr 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.,ff. Biases include the pool temperature and code validation biases as well as the fission product and actinide worth bias and the assembly envelope expansion bias. Uncertainties account for allowable variations within the real model whether they are physical (manufacturing tolerances), analytical (depletion) or measurement related (burnup measurement uncertainty).
84.1.2.1 Bias & Uncertainty Descriptions The following sections describe the biases and uncertainties that are accounted for in this analysis.
84.1.2.1.1 Manufacturing Tolerances See Section 4.1.2.1.1 of Reference 2 for additional details concerning manufacturing tolerances.
The fuel and rack tolerances that are considered in the analysis are: 1. Rack cell ID 2. Rack cell pitch 3. Rack cell wall thickness.
- 9. Instrument tube ID 10. Pellet OD 11. Fuel initial enrichment I Eccentric; positioning has been changed from an uncertainty to a bias. The eccentric positioning modeling methodology is described in Section S4. l .2. l .6. Reference 2 included Fuel Rod Pitch and Eccentric WCAP-17400-NP September 2017 Supplement 1, Revision 2 WESTINGHOUSE NON-PROPRIETARY CLASS 3 Positioning in the list of manufacturing tolerances.
For this analysis, the fuel rod pitch has been incorporated into a new bias called the Assembly Envelope Expansion Bias, described in Section S4.1.2.1.9.
S4.1.2.1.2 Burn up Measurement Uncertainty See Section 4.1.2.1.2 of Reference
- 2. S4.1.2.1.3 Depletion Uncertainty See Section 4.1.2.1.3 of Reference
- 2. S4.1.2.1.4 Fission Product Worth and Actinide Bias 4-2 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-7109, "An Approach for Validating Actinide and Fission Product Burnup Credit Criticality Safety Analyses-Criticality (keff) 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 keff 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.
[ S4.1.2.1.5 Operational Uncertainty See Section 4.1.2.1.5 of Reference
- 2. WCAP-17400-NP September 2017 Supplement 1, Revision 2 WESTINGHOUSE NON-PROPRIETARY CLASS 3 4-3 84.1.2.1.6 Eccentric Fuel Assembly Positioning Bias Eccentric positioning is calculated in Reference 2 using a [ Figure S4-1 Allowable Storage Arrays Reference 2 Eccentric Positioning Modeling Schematic (a) Fuel Assemblies Together (b) Fuel Assemblies Apart The modeling strategy shown in Figure S4-1 provides an overly conservative representation of any expected fuel eccentricity.
Because the reactivity impact will be treated as a bias rather than uncertainty, a more realistic, although still conservative modeling methodology has been used. [ WCAP-17400-NP September 2017 Supplement 1, Revision 2 WESTINGHOUSE NON-PROPRIETARY CLASS 3 4-4 a,c Figure S4-2 Updated IFBA Bearing Fuel Eccentric Positioning Modeling Schematic (a) Fuel Assemblies Together (b) Fuel Assemblies Apart The modeling strategy utilized in Figure provides for [ ]",c An example of the Array G eccentric positioning model is shown in Figure S4-3. The Array G eccentric positioning model uses the same boundary conditions.
[ a,c Figure S4-3 Updated IFBA Bearing Fuel Eccentric Positioning Modeling Schematic Illustrating the Array G "Out" Eccentric Positioning Model WCAP-17400-NP September 2017 Supplement 1, Revision 2 WESTINGHOUSE NON-PROPRIETARY CLASS 3 4-5 S4.1.2.1.7 Other Uncertainties See Section 4.1.2.1. 7 of Reference
- 2. 84.1.2.1.8 Pool Temperature Bias See Section 4.1.2.1. 8 of Reference
- 2. 84.1.2.1.9 Assembly Envelope Expansion Bias The assembly envelope expansion bias is comprised of [ The fuel assembly grids expand over the course of operation in the reactor, leading to a larger overall assembly envelope.
This phenomenon, has two separate potential effects on spent fuel pool reactivity.
The first effect is ciue to the change in isotopic inventory due to the larger pin pitch impacting the in core energy spectrum.
The second effect is the reactivity impact due to the potential pin pitch increase during storage. Because the grid springs and tabs which initially hold fuel rods in place relax during reactor operation, it is believed that both during and after operation, fuel is randomly oriented within each slightly expanded fuel pin cell in the grid. Without any industry data to support this hypothesis, a very conservative methodology such that [ WCAP-17400-NP September 2017 Supplement 1, Revision 2 WESTINGHOUSE NON-PROPRIETARY CLASS 3 WCAP-17400-NP I 4-6 September 2017 Supplement 1, Revision 2 WESTINGHOUSE NON-PROPRIETARY CLASS 3 l 84.1.2.1.10 Borated and Unborated Biases and Uncertainties Prairie Island Technical Specifications require the SFP k,,1rto be :S 0.95 under borated conditions accounting for all applicable biases and uncertainties.
[ 84.1.2.2 Storage Array Biases & Uncertainties Results See Section 4.1.2.2 of Reference 2, excluding the reference to fuel operated in cycles 1-4. 4-7 WCAP-17400-NP September 2017 Supplement 1, Revision 2 WESTINGHOUSE NON-PROPRIETARY CLASS 3 84.1.2.2.1 Storage Array Biases & Uncertainties for IFBA Bearing Fuel Table S4-1 Biases & Uncertainties for Array A IFBA Bearing Fuel WCAP-17400-NP 4-8 September 2017 Supplement 1, Revision 2 a,c WESTINGHOUSE NON-PROPRIETARY CLASS 3 Table 84-2 Biases & Uncertainties for Array B IFBA Bearing Fuel WCAP-17400-NP 4-9 September 2017 Supplement 1, Revision 2 a,c WESTINGHOUSE NON-PROPRIETARY CLASS 3 4-10 Biases and Uncertainties for Array C IFBA Bearing fuel were not specifically calculated.
See Section SS.l more information on Array C (Fuel Category 1) storage. Table S4-3 Biases & Uncertainties for Array D IFBA Bearing Fuel WCAP-17400-NP September 2017 Supplement 1, Revision 2 a,c WESTINGHOUSE NON-PROPRIETARY CLASS 3 Table S4-4 Biases & Uncertainties for Array E IFBA Bearing Fuel WCAP-17400-NP 4-11 September 2017 Supplement 1, Revision 2 a,c I I I I I I I I I I I , , I I I I I I I WESTINGHOUSE NON-PROPRIETARY CLASS 3 Table 84-5 Biases & Uncertainties for Array G IFBA Bearing Fuel WCAP-17400-NP 4-12 September 2017 Supplement 1, Revision 2 a,c WESTINGHOUSE NON-PROPRIETARY CLASS 3 4-13 84.1.2.2.2 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. 84.1.2.3 Consolidated Rod Storage Canister Biases & Uncertainties Results IFBA Bearing fuel is not considered for consolidation is therefore prohibited for storage within I
- Array F from Section 3. 7.1 of Reference 2 (i.e. there is no Category 7 IFBA Bearing fuel). I A single interface comprising Array A and Array F was evaluated for storage with the Consolidated Rod Storage Canister.
[ 84.1.2.4 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% 10 B, because the is.otopic concentration of boron can vary as low as 19.4 at% 10 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 19.4at% JOB. It is demonstrated that 400 ppm at 19.4 at% JOB is sufficient to comply with the acceptance criterion ofkeff:S:
0.95 under.all normal conditions (see Table S4-6). Addit'ionally, Table S4-6 data identify the limiting storage array and the soluble boron concentration required to meet a keff:S: 0.95. WCAP-17400-NP September 2017 Supplement 1, Revision 2 WESTINGHOUSE NON-PROPRIETARY CLASS 3 Table S4-6 Results For Normal Operations with 400 ppm a,c S4.3 RODDED OPERATION See Section 4.3 of Reference
- 2. The addition ofIFBA to 422 V+ fuel,will not negatively impact the change in reactivity seen from rodded operations, since the presence ofIFBA already hardens the spectrum early in depletion and operating rodded will have less overall additional impact as a result. Rodded operation for Fuel Not Operated in Cycles 1-4 from Reference 2 conclusions remain valid for IFBA Bearing fuel. However, final acceptance of rodded operations from Reference 1 determined that 100 MWd/MTU of rodded operations was acceptable.
See Section S5.2 for additional details. S4.4 NORMAL CONDITIONS S4.4.1 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. S4.4.3 Type 3 Normal Conditions 4-14 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 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 September 2017 Supplement 1, Revision 2 WESTINGHOUSE NON-PROPRIETARY CLASS 3 4-15 Since fresh IFBA Bearing fuel is less reactive than the same enrichment fresh non-IFBA Bearing fuel, conclusions in Reference 2 for the failed fuel pin basket and fuel rod storage canister remain applicable to IFBA Bearing fuel. 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 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. To evaluate this accident, [ WCAP-17400-NP September 2017 Supplement 1, Revision 2 WESTINGHOUSE NON-PROPRIETARY CLASS 3 4-16 84.5.2 Inadvertent Removal of an RCCA I See Section 4.5.2 of Reference
- 2. 84.5.3 Spent Fuel Temperature Outside Operating Range These cases were not reevaluated since the Reference 2 reactivity, including biases and uncertainties is less than 0.90 indicating significant margin is available.
Additionally based on the results from Reference 2, the pool temperature outside of operating range cases do not contain the limiting accident condition.
84.5.4 Dropped & Misplaced Fresh Assembly See Section 4.5.4 of Reference
- 2. 84.5.4.1.1 Accident Results Table S4-7 gives the results of the limiting single,assembly misload accident (890 ppm). 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 soluble boron is required to mitigate a Type II multiple misload, leaving significant margin (in tenns of soluble boron) to the proposed Technical Specification limit (including 100 ppm of uncertainty) of2400 ppm soluble boron. WCAP-17400-NP September 2017 Supplement 1, Revision 2 WESTINGHOUSE NON-PROPRIETARY CLASS 3 5-1 SS. 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 S3.7.l. This section also contains the restrictions placed on the various storage arrays such as placement of non-fuel items and an of normal SFP activities which are bounded by this analysis.
SS.l BURNUP REQUIREMENTS
& RESTRICTIONS ON STORAGE ARRAYS Assembly storage is controlled through the storage arrays defined in Section S3.7. l. 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 burnup, enrichment and decay time as provided by Table S5-2 through Table S5-11, with the exception of Fuel Category 1 assemblies.
Fuel Category 1 assemblies are defined in the notes to Table S5-l. Fuel Category 7 from Reference 2 (consolidated rod storage) is not permitted with IFBA Bearing fuel.
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% 235 U; no bumup is required.
- 3. Fuel Categories 2 through 6 are determined from the coefficients provided.
Array C containing Fuel Category 1 assemblies is not explicitly analyzed in this supplemental report. However, Fuel Category 1 from Reference 2 will bound the same enrichment IFBA Bearing fuel. This is because the same amount of fresh fuel of the same type with integral absorber will remain less reactive than fresh fuel without integral absorber.
Since no burnup is required for 5.0 wt% 235 U for Fuel Category 1 assemblies from Reference 2, no analysis is necessary.
Note that in the burnup coefficient requirement tables, there is an enrichment range given for the Burnup Requirement Coefficients.
The upper bound of the range for the burnup requirement coefficients (5.0 wt% 235 U) cannot be exceeded.
However,
- enrichments below the lower bound may be used. Negative values obtained from such usage can be treated as a requirement of 0 GWd/MTU, while storing fuel based on positive burnup requirements generated below the low end of the enrichment range is conservative.
WCAP-17400-NP September 2017 Supplement 1, Revision 2
. WESTINGHOUSE NON-PROPRIETARY CLASS 3 5-2 85.1.1 Requirements for IFBA Bearing Fuel Table SS-2 Fuel Category 2 Burnup Requirement Coefficients r Coefficients Decay Time (yr) Ai A2 A3 A4 0 -1.1649 15.1994 -56.7939 65.2864 Notes: 1. All relevant uncertainties are explicitly included in the criticality analysis.
For instance, no additional allowance for burnup uncertainty enrichment uncertainty is required.
For a fuel assembly to meet the requirements of a Fuel Category, the assembly burnup 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 1
- En 3 + A 2
- En 2 + A 3
- 2. Initial enrichment, En, is the nominal 235 U enrichment.
Any enrichment between 2.9 wt% 235 U and 5.0 wt% . Table SS-3 Fuel Category 2 Burnup Requirements (GWd/MTU) wt% 235u Decay Time (yr) 2.90 3.40 4.00 4.50 5.00 0 0.000 2.107 6.748 11.351 15.690 Notes: 1. This table is included as an example, the burnup requirements will be calculated using the coefficients provided.
WCAP-17400-NP September 2017 Supplement 1, Revision 2 WESTINGHOUSE NON-PROPRIETARY CLASS 3 5-3 Table S5-4 Fuel Category 3 Burnup Requirement Coefficients Coefficients Decay Time (yr) Ai A2 A3 A4 0 -0.2213 2.6959 -0.9136 -11.0959 5 -0.2568 2.9933 -2.0421 -9.5730 10 -0.3012 3.4074 -3.5247 -7.7578 15 -0.2790 3.1007 -2.4261 -8.9334 20 -0.2959 3.2578 -3.0233 -8.1560 Notes: I. 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 burn up must exceed the "minimum burn up" (GW d/MTU) given by the curve fit for the assembly "decay time" and "initial enrichment." The specific minimum bumup required for each fuel assembly is calculated from the following equation:
BU= A 1
- En 3 + A 2
- En 2 + A 3 *
- 2. Initial enrichment, En, is the nominal 235 U enrichment.
Any enrichment between 2.5 wt% 235 U and 5.0 wt% 235 U may 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 S5-5 Fuel Category 3 Burnup Requirements (GWd/MTU) wt% 235u Decay Time (yr) 2.50 3.40 4.00 4.50 5.00 0 0.000 8.264 14.221 19.219 24.071 5 0.000 7.993 13.716 18.451 22.949 10 0.000 7.809 13.385 17.934 I 22.154 15 0.000 7.696 13.117 17.514 21.579 20 0.000 7.595 12.938 17.246 21.185 Notes: I. This table is included as an example, the bumup requirements will be calculated using the coefficients provided.
WCAP-17400-NP September 2017 Supplement 1, Revision 2 WESTINGHOUSE NON-PROPRIETARY CLASS 3 5-4 Table SS-6 Fuel Category 4 Burnup Requirement Coefficients Coefficients Decay Time (yr) Ai Az A:l A4 0 1.3659 -14.9709 63.0347 -72.9223 Notes: I. 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 burn up must exceed the "minimum burnup" (GW d/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 1
- En 3 + A 2
- En 2 + A 3 *
- 2. Initial enrichment, En, is the nominal 235 U enrichment.
Any enrichment between l.8 wt% 235 U and 5.0 wt% 235 U may be used. Table SS-7 Fuel Category 4 Burnup Requirements (GW d/MTU) wto/o z3su 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: I. This table is included as an example, the 'burnup requirements will be calculated using the coefficients*
provided.
WCAP-17400-NP September 2017 Supplement 1, Revision 2 WESTINGHOUSE NON-PROPRIETARY CLASS 3 5-5 Table S5-8 Fuel Category 5 Burnup Requirement Coefficients Coefficients Decay Time (yr) Ai Al A3 A4 0 -0.0593 0.1023 15.3729 -26.8802 5 -0.2615 2.1569 8.0609 -19.3100 10 -0.2877 2.3547 7.0910 -18.0783 15 -0.3628 3.2525 3.4409 -14.0374 20 -0.3144 2.8751 3.9652 -14.0590 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 burn up must exceed the "minimum burnup" (GW d/MTU) given by the curve fit for the assembly .decay time" and "initial endchment." The specific minimum burnup required for each fuel assembly is calculated from the following equation:
BU= A 1
- En 3 + A 2
- En 2 + A 3
- En+ A 4 \ 2. Initial enrichment, En, is the nominal 235 U enrichment.
Any enrichment between 1.75 wt% 235 U and 5.0 wt% 235 U may 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 S5-9 Fuel Category 5 Burnup Requirements (GWd/MTU) wto/o 23su Decay Time (yr) 1.75 3.40 4.00 4.50 5.00 0 0.000 24.240 32.453 38.966 45.130 5 0.000 22.753 30.708 36.813 42.230 10 0.000 21.944 29.549 . 35.298 40.282 15 0.000 21.002 28.547 34.250 39.130 20 0.000 20.302 27.682 33.356 38.345 Notes: 1. This table is included as an example, the btirnup requirements will be calculated using the coefficients provided.
' WCAP-17400-NP September 2017 Supplement 1, Revision 2 I I I I WESTINGHOUSE NON-PROPRIETARY CLASS 3 5-6 Table 85-10 Fuel Category 6 Burnup Requirement Coefficients Coefficients Decay Time (yr) Ai Az AJ A4 0 0.3813 -4.7336 32.9021 -44.1171 5 0.5076 -5.8228 34.7320 -44.7082 10 0.2765 -3.4168 26.3694 -36.3056 15 OJ971 -2.5921 23.2490 -3i.9993 20 0.0841 -1.4693 19.5,003 -29.3159 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 bumup" (GW d/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 1
- En 3 + A 2
- En 2 + A3
- En+ A 4 2. Initial enrichment, En, is the nominal 235 U enrichment.
Any enrichment between 1.7 wt% 235 U and 5.0 wt% 235 U inay 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 85-11 Fuel Category 6 Burnup Requirements (GWd/MTU) wto/o z3su Decay Time (yr) 1.70 3.40 4.00 4.50 5.00 0 0.000 28.016 36.157 42.833 49.716 5 0.000 26.020 33.541 39.929 46.832 -* 10 0.000 24.720 32.199 38.363 44.684 15 0.000 23.829 31.138 37.092 43.081 20 0.000 23.305 30.559 36.346 41.966 Notes: I 1. This table is included as an example, the burnup requirements will be calculated using the coefficients
- provided.
September 2017 Supplement 1, Revision 2 WESTINGHOUSE NON-PROPRIETARY CLASS 3 5-7 S5.1.2 Bu'rnup Requirements for Fuel Operated during Cycles 1-4 IFBA Bearing fuel was not present in Cycles 1-4 and no anaJys1s is performed.
The results of Section .5.1.2 of Reference 2 remain valid for fuel operated in Cycles 1-4. S5.1.3 Decay Time Interpolation See Section 5.1.3 of Reference
- 2. S5.2 RODDED OPERATION Prairie Island has experienced load follow operation in the past as described in Section 4.3 of Reference
- 2. The addition ofIFBA to 422 V+ fuel will not negatively impact the change.in reactivity seen from rodded operations as discussed in Section S4.3; therefore rodded operations conclusions from Reference 2 indicating up to .1000 MW d/MTU of rodded operations remain valid. Howeyer, as a result of the commitments defined Reference 1, if an IFBA Bearing fuel assembly experiences more than 100 MWd/MTU of core average full-power rodded operation, the bumup of the assembly experienced while rodded will not be credited.
S5.3 INTERFACE CONDITIONS See Section 5.3 of Reference
- 2. SS.4 NORMAL CONDITIONS See Section 5.4 of Reference
- 2. S5.4.1 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. S5.4.3 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 fr<;>m Reference 2 is not a valid storage array for IFBA Bearing fuel. ' S5.4.4 Type 4 Normal Conditions See Section 5.4.4 of Reference
- 2. WCAP-17400-NP September 2017 Supplement 1, Revision 2 i I
- I WESTINGHOUSE NON-PROPRIETARY CLASS 3 5-8 S5.4.5 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 SFP to keep k.,ff :'S 0.95 under all normal and credible accident scenarios.
Under normal conditions, the requirement is 400 ppm of soluble boron. The boron dilution endpoint is greater than 400 ppm demonstrating that under the worst credible dilution event k.,ff is maintained at:::; 0.95. Under non-dilution accident conditions including a full pool misload of fresh fuel, 2030 ppm of soluble boron is required to ensure k.,ff:'S 0.95 which leaves significant margin to the proposed Technical Specification value of2500 ppm (analysis assumes 2400 ppm maximum with an inclusion of 100 ppm uncertainty).
WCAP-17400-NP September 2017 Supplement 1, Revision 2 WESTINGHOUSE NON-PROPRIETARY CLASS 3 S6. BURNUP REQUIREMENTS FOR ALL FUEL NOT OPERATED.IN CYCLES 1-4 INCLUDING IFBA BEARING FUEL 6-1 Both this supplemental report and Reference 2 contain identical storage array descriptions, for which burnup requirements are determined for six fuel categories (seven for Reference 2). The design difference between the two analyses is the presence of IFBA within the fuel during depletion in this supplemental analysis.
In addition, the following updates were made:
- Change in the fission product and actinide worth evaluation
- Addition of the multiple misload analyses
- Change in input of cycle average soluble boron during depletion from 900 ppm to 1000 ppm.
- Usage of IFBA Bearing fuel specific input for axial burnup profile and moderator temperature profile input
- Modeling of annular blanketed fuel as annular fuel instead of solid for both depletion and criticality calculations These storage arrays (A, B, C, D, E and G) are seen in Section S3. 7 .1, 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, although the acceptability of the Array A and Array F interface is confirmed.
A single set of conservative burnup requirement coefficients (curves) which bounds both IFBA Bearing fuel and Fuel Not Operated in Cycles 1-4 from Reference 2 is developed which remains conservative for all burnup requirements and remains conservative for all accident criterion.
This section discusses the process used to develop a single set of burn up coefficients considering the different bounding input used for Fuel Not Operated in Cycles 1-4 from Reference 2 and IFBA Bearing fuel and concludes with a single set of burn up coefficients for storage of all fuel operated after cycles 1-4, including IFBA Bearing fuel. An assessment of the applicability of the accident analysis is also given. S6.1 IMPACT OF ECCENTRIC POSITIONING AND ASSEMBLY ENVELOPE EXPANSION BIAS METHODOLOGY CHANGE TO REFERENCE 2 BURNUP REQUIREMENTS While design input for Fuel Not Operated in Cycles 1-4 from Reference 2 and for IFBA Bearing fuel evaluated in this report can differ, to utilize a single set of burnup requirement coefficients, the bias and uncertainty data should be consistent.
As a result, the reactivity impact of the updated eccentric positioning methodology and introducing the assembly envelope expansion bias methodology is determined for Fuel Not Operated in Cycles 1-4 from Reference
- 2. S6.1.1 Updated Eccentric Positioning Methodology Reference 2 Reactivity Impact The modeling methodology from Reference 2 was updated to determine the eccentric positioning reactivity impact as discussed in Section S4. l .2. l .6 for Fuel Not Operated in Cycles 1-4 from Reference
- 2. Table S6-1 shows the reactivity worth from the original Reference 2 determined impact and the WCAP-17400-NP September 2017 Supplement 1, Revision 2 WESTINGHOUSE NON-PROPRIETARY CLASS 3 updated impact. Recall that the updated impact is incorporated as a bias while the original Reference 2 impact was incorporated as an uncertainty.
6-2 I Table 86-1 Eccentric Positioning Bias Worth (Ak) I I I I I I I S6.1.2 Assembly Envelope Expansion Bias Quantification for Fuel Not Operated in Cycles 1-4 from Reference 2 The Fuel Rod Pitch Uncertainty documented in Reference 2 has been replaced by the Assembly Envelope Expansion Bias described in Section S4. l .2. l .9. This includes [ ]"'c Assembly Envelope Expansion Bias Worth for Fuel Not Operated in Cycles 1-4 from Reference 2 is given in Table S6-2. Table 86-2 Assembly Envelope Expansion Bias Worth (Ak) for Reference 2 1 Biases and uncertainties determined at 1.80 wt% 235 U which was storable for Array G alone. Both Array G and Array D contain Category 5 fuel, with evaluated burnup limits for Array G bounding.
Array D max fresh enrichment was determined to be 1.75 wt% 235 U. For Array G values to be bounding at all enrichments for Fuel Category 5, the fresh max fresh enrichment was set to 1.75 wt% 235 U. WCAP-17400-NP September 2017 Supplement 1, Revision 2 a,c WESTINGHOUSE NON-PROPRIETARY CLASS 3 6-3 S6.1.3 Final Combined Storage (Burnup) Requirements Bumup requirements are updated from Reference 2 as a result of the change in Eccentric Positioning methodology and the incorporation of the Assembly Envelope Expansion Bias, including any change to the burnup measurement and depletion uncertainty because they are functions of the final burnup storage limits. Combined bumup requirements coefficients and example bumup requirements are generated as the higher of the burn up requirements between the updated Reference 2 bumup requirements and the IFBA Bearing fuel burnup requirements from Section S5.1.1 and are given in Table S6-3 through Table S6-12. Section S6.2 compares the final results to the calculated results for both IFBA bearing and combined fuel. Table 86-3 Fuel Category 2 Burnup Requirement Coefficients Coefficients Decay Time (yr) Ai A2 A3 A4 0 -1.1640 15.1916 -56.7743 65.2736 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 bum up must exceed the "minimum bumup" (GW d/MTU) given by the curve fit for the assembly "decay time'.' and "initial enrichment." The specific minimum bumup requirecj for each fuel assembly is calculated from the following equation:
BU= A 1
- En 3 + A 2
- En 2 + A 3 *
- 2. Initial enrichment, En, is the nominal 235 U Any enrichment between 2.9 wt% 235 U and 5.0 wt% 235 U may be used. Table 86-4 Fuel Category 2 Burnup Requirements (GWd/MTU) . wt% 235u Decay Time (yr) 2.90 3.40 4.00 4.50 5.00 0 0.000 2.107 6.746 11.350 15.693 Notes: 1. This table is included as an example, the bumup requirements will be calculated using the coefficients provided.
WCAP-17400-NP September 2017 Supplement 1, Revision 2 WESTINGHOUSE NON-PROPRIETARY CLASS 3 6-4 Table 86-5 Fuel Category 3 Burnap Requirement Coefficients Coefficients Decay Time (yr) Ai Ai A3 A4 0 -0.2213 2.6959 -0.9136 -11.0959 5 -0.2568 2.9933 -2.0421 -9.5730 10 -0.3012 3.4074 -3.5247 -7.7578 15 -0.2790 3.1007 -2.4261 -8.9334 20 -0.2959 3.2578 -3.0233 -8.1560 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 burn up must exceed the "minimum burn up" (GW d/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 1
- En 3 + A 2
- En 2 + A3
- En+ A 4 2. Initial enrichment, En, is the nominal 235 U enrichment.
Any enrichment between 2.5 wt% 235 U and 5.0 wt% 235 U may 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 S6-6 Fuel Category 3 Burnap Requirements (GWd/MTU) wt% 235u Decay Time (yr) 2.50 3.40 4.00 4.50 5.00 0 0.000 8.264 14.221 19.219 24.071 5 0.000 7.993 13.716 18.451 22.949 10 0.000 1.809 13.385 17.934 22.154 15 0.000 7.696 13.117 17.514 21.579 20 0.000 7.595 12.938 17.246 21.185 Notes: 1. This table is included as an example, the burnup requirements will be calculated using the coefficients provided.
WCAP-17400-NP September 2017 Supplement 1, Revision 2 WESTINGHOUSE NON-PROPRIETARY CLASS 3 6-5. Table S6-7 Fuel Category 4 Burnup Requirement Coefficients Coefficients*
Decay Time (yr) Ai Al \ A3 A4 0 1.3659 -14.9709 63.0347 -72.9223 Notes: ' I. 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 burn up must exceed the "minimum burn up" (GW d/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 1
- En 3 + A 2
- En 2 + A 3 *En.+ A 4 2. Initial enrichment, En, is the nominal 235 U enrichment.
Any enrichment between 1.8 wt% 235 U and 5.0 wt% 235 U may be used. Table 86-8 Fuel Category 4 Burnup Requirements (GWd/MTU) wto/o 235 U 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: I. This table is included as an example, the burnup requirements will be calculated using the coefficients provided.
WCAP-17400-NP September 2017 Supplement 1, Revision 2 WESTINGHOUSE NON-PROPRIETARY CLASS 3 6-6 Table 86-9 Fuel Category 5 Burnup Requirement Coefficients Coefficients Decay Time (yr) Ai Az A3 A4 0 0.1255 -1.6774 20.7491 -31.8434 5 -0.0520 0.0723 14.5901 -25.4754 . 10 0.1681 -2.2188 21.4991 -31.7286 15 -0.3431 3.0482. 4.0932 -14.6591 20 -0.2576 2.2345 6.1980 -16.3085 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 burn up must exceed the "minimum bum up" (GW d/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 1
- En 3 + A 2
- En 2 + A 3 *
- 2. Initial enrichment, En, is the nominal 235 U enrichment.
Any enrichment between 1.75 wt% 235 U and 5.0 wt% 235 U may 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 86-10 Fuel Category 5 Burnup Requirements (GWd/MTU) wt% 235u Decay Time (yr) 1.75 3.40 4.00 4.50 5.00 0 0.000 24.246 32.347 38.997 45.655 5 0.000 22.923 30.714 36.906 42.783 10 0.600 22.327 29.526 35.405 41.310 15 0.000 21.010 28.527 34.222 39.125 20 0.000 20.471 27.750 33.358 38.344 Notes: 1. This table is included as an example, the burnup requirements will be calculated using the coefficients provided.
WCAP-17400-NP September 2017 Supplement 1, Revision 2 I I I* I I WESTINGHOUSE NON-PROPRIETARY CLASS 3 6-7 Table 86-11 Fuel Category 6 Burnup Requirement Coefficients Coefficients Decay Time (yr) Ai Az A3 A4 0 0.6666 -7.4900 \ 41.2094 -51.6844 5 0.5686 -6.3968 36.4332 -46.2433 10 0.3895 -4.5024 29.6132 -39.2399 15 0.1962 -2.5813 23.2107 -32.9620 20 0.1192 -1.7984 20.4749 -30.1950 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 burnup 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 1
- En 3 + A 2
- En 2 + A 3
- 2. Initial enrichment, En, is the nominal 235 U enrichment.
Any enrichment between 1. 7 wt% 235 U and 5 .0 wt% 235 U may 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 86-12 Fuel Category 6 Burnup Requirements (GWd/MTU) wt% 235u Decay Time (yr) 1.70 3.40 4.00 . 4.50 5.00 0 0.000 28.043 35.976 42.829 50.438 5 0.000 26.031 33.531 39.985 47.078 10 0.000 24.706 32.103 38.339 44.954 15 0.000 23.826 31.137 37.094 43.084 j 20 0.000 23.315 30.559 36.387 42.120 Notes: 1. This table is included as an example, the burnup requirements will be calculated using the coefficients provided.
WCAP-17400-NP September 2017 Supplement 1, Revision 2 WESTINGHOUSE NON-PROPRIETARY CLASS 3 S6.2 COMPARISON OF CALCULATED BURNUP REQUIREMENTS AND FINAL COMBINED BURNUP REQUIRMENTS
,* Table S6-13 through Table S6-17 are provided to demonstrate the conservatism of the final combined bumup requirements compared to the calculated bumup requirements for IFBA Bearing fuel and Combined IFBA Bearing fuel and updated Reference 2 requirements.
Table 86-13 Fuel Category 2 Burnap Requirements Comparison (GWd/MTU) 6-8 WCAP-17400-NP September 2017 Supplement 1, Revision 2 WESTINGHOUSE NON-PROPRIETARY CLASS 3 I Table 86-14 Fuel Category 3 Burnup Requirements Comparison (GWd/MTU)
I I I I I I I I I I I I I Table 86-15 Fuel Category 4 Burnup Requirements Comparison (GWd/MTU) 6-9 September 2017 Supplement 1, Revision 2 a,c a,c WESTINGHOUSE NON-PROPRIETARY CLASS 3 I Table S6-16. Fuel Category 5 Burnup Requirements Comparison (GWd/MTU)
I I I I I I I I I I I I I I WCAP-17400-NP 6-10 September 2017 Supplement 1, Revision 2 a,c WESTINGHOUSE NON-PROPRIETARY CLASS 3 6-11 . Table 86-17 Fuel Category 6 Burnup Requirements Comparison (GWd/MTU) 86.3 METHODOLOGY AND INPUT COMPARISON 86.3.1 Methodology Comparison The development ofburnup requirements for IFBA Bearing fuel and Fuel Not Operated in Cycles 1-4 utilize the same basic methodology, except for the change to [ WCAP-17400-NP September 2017 Supplement 1, Revision 2 a,c WESTINGHOUSE NON-PROPRIETARY CLASS 3 6-12 S6.3.2 Input Comparison and Conclusion A comparison of depletion input for IFBA Bearing fuel and "Fuel Not Operated in Cycles 1 analysis is given in Table S6-18. Additionally, input requirements for the misload accident are updated to incorporate a multiple mis load, 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. Table S6-18 Comparison oflnput Core Operational Parameters During Depletion Parameter Reference 2 Modeled Value IFBA Bearing Fuel Analysis Modeled Value Fuel Type 422V+ 422V+ Core Depletion Power, MWt 2789 2789 Axial Moderator Temperature Table 3-9, Reference 2 Table S3-3 Distribution Relative Axial Burnup Profile Table 3-9, Reference 2 Table S3-3 Core Outlet Moderator Temperature, °F 622.5 to 639.02 605.34 to 620.27 Core Inlet Moderator Temperature, °F 548.47 536.48 to 541.68 Soluble Boron Concentration, ppm 900.0 1000.0 Soluble Boron 10 B atom percent, % 19.4 19.4 Minimum Core Loading, kg U 48740 48740 Fuel Pellet Theoretical Density,%
97.5 97.5 System Pressure, psia 2250 2250 Single Pump Coolant Flow, gpm 89000 89000 Maximum Number ofIFBA rods 0 120 IFBA 10 B linear density, mg/in NIA 2.655 (l.5X) (Thickness)
IFBA length, (in) NIA 132.00 Blanket Model Solid, Fully Enriched Annular, Fully Enriched Blanket Length (top/bottom), inches None 616 Note: The Core Depletion Power input is the result of multiplication of the Core Power multiplied by the Maximum Instantaneous Peak Assembly Average Relative Power (1.54 ). The data in Table S6-18 show that aside from the addition ofIFBA to the 422V+ fuel and associated modeling of the annular blanket region, the soluble boron concentration and axial burnup and moderator temperature profile inputs were changed for the depletion calculations.
Future fuel storage 1nust meet either the assumptions of the Reference 2 methodology and input assumptions or the IFBABearing fuel methodology and input assumptions.
- WCAP-17400-NP September 2017 Supplement 1, Revision 2 I I I WESTINGHOUSE NON-PROPRIETARY CLASS 3 6-13 S6.3.3 Accidents and Soluble Boron Credit Review Table 86-19 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 S6-19 Soluble Boron Credit Comparison IFBA Bearing Fuel Reference2 Condition (ppm) (ppm) Normal Operations 2 340 359 3 Single Misload 890 910 Multiple Misload (Type I) 1380 NIA Multiple Misload (Type II) 2030 NIA Tech. Spec. Limit 2400 4 1800 Note: All soluble boron concentrations are based on 19.4 at% 1°B Table 86-19 data indicate that the value reported for normal and single misload accident conditions in Reference 2 are lower than reported in Table 86-19 for the analogous scenario.
Less finely spaced checks were performed for the soluble boron credit calculations supporting Reference 2, contributing to small differences although the overall conservatism of the soluble boron requirements documented in
- Reference 2 is ma.intained.
The addition of the multiple mis load 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, the combined fuel bumup requirement coefficients can be appropriately used for all Fuel Not Operated in Cycles 1-4 including IFBA Bearing fuel. The 2030 ppm of soluble boron determined for multiple misloads was determined for all fresh fuel such that updated depletion input is not necessary and this value is accurate for both IFBA Bearing and non-IFBf\
Bearing fuel. *S6.3.4 Comparison Conclusions A set of bounding bum up requirement coefficients was developed based on the Reference 2 bum up requirements updated to incorporate eccentric positioning as a bias and the assembly envelope expansion bias and IFBA Bearing fuel bl1mup requirements under which all fuel expected for storage at Prairie Island can be stored (with the exception of fuel operated in Cycles 1-4 which is covered in Reference 2). Accident and interface conditions have been reviewed and reanalyzed when necessary, including the incorporation of a full pool assembly misload which can be accommodated with significant soluble boron margin remaining.
No impact to the normal conditions assessment has been found. The Array A to Array F interface condition was reanalyzed and shown to be acceptable for IFBA bearing fuel and for .Fuel Not Operated in Cycles 1-4 in Reference
- 2. As a result of these findings, it is conservative to utilize the bumup requirement coefficients determined for the combination of updated Reference 2 bumup 2 Both credit 400 ppm soluble boron. 340 ppm was not explicitly checked for Fuel Not Operated in Cycles 1-4. 3 350 ppm soluble boron determined in Reference 2 at19.9 at% 10 B corresponds to 359 ppm at 19.4 at% 10 B. 4 Based on a Proposed Tech. Spec. limit of 2500 ppm with 100 ppm uncertainty.
WCAP-17400-NP September 2017 Supplement 1, Revision 2 WESTINGHOUSE NON-PROPRIETARY CLASS 3 6-14 requirements and IFBA Bearing fuel burnup requirements for the storage of all fuel which has been operated at Prairie Island Units 1 and 2 except for the fuel operated in cycles 1-4 for Prairie Island which is stored according to the requirements given in Reference
- 2. WCAP-17400-NP September 2017 Supplement 1, Revision 2 WESTINGHOUSE NON-PROPRIETARY CLASS 3 7-1 S7. REFERENCES
- 1. "Prairie Island Nuclear Generating Plant, Units 1 and 2 -Issuance of Amendments re: Spent Fuel Pool Criticality Changes (TAC NOS: ME6984 and ME6985),
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, "Staff Guidance Regarding the Nuclear Criticality Safety Analysis for Spent Fuel Pools," DSS-ISG-2010-01, Accession Number MLl 10620086, Nuclear Regulatory Commission, .Rockville, MD, October 2011. 4. J. M. Scaglione, et al., "An Approach for Validating Actinide and Fission Product Burnup Credit Criticality Safety Analyses-Criticality (ketr) Predictions,
NUREG/CR-7109, Oak Ridge National Laboratory, Oak Ridge, TN, April 2012. WCAP-17400-NP September 2017 Supplement 1, Revision 2 WESTINGHOUSE NON-PROPRIETARY CLASS 3 A-1 APPENDIX A VALIDATION OF SCALE 5.1 See Reference 2, Appendix A for the Validation of SCALE 5.1. WCAP-17400-NP September 2017 Supplement 1, Revision 2