ML030140059
| ML030140059 | |
| Person / Time | |
|---|---|
| Site: | Saint Lucie, Turkey Point  |
| Issue date: | 12/11/2002 |
| From: | Florida Power & Light Co |
| To: | Office of Nuclear Reactor Regulation |
| References | |
| Download: ML030140059 (41) | |
Text
A6Id FPL NRC-FPL Meeting St. Lucie and Turkey Point Spent Fuel Storage License Amendments Carl Bible December 11, 2002
7 T. 17zz FPL Spent Fuel Storage
- Meeting Objectives
- Brief NRC staff on license amendment requests
"° St. Lucie (Unit 1, 2) Cask Pit Rack
"° Turkey Point Cask (Unit 3, 4) Area Rack
"° St. Lucie Unit 1 Boraflex Remedy
- Staff concurrence on approval dates 2
FPL Spent Fuel Storage FPL Organization
- Fuel Storage Projects e Bible - Manager 9 Adams - St. Lucie Cask Pit Rack, project licensing
- Kao - Turkey Point Cask Area Rack
- Sharp - St. Lucie Boraflex Remedy
- Plant Licensing Liaison
- Frehafer - St. Lucie
- Mihalakea - Turkey Point 3
FPL Spent Fuel Storage
- Near-Term Fuel Storage Licensing Actions Amendment Submit Need St. Lucie
- Unit 1/2 Crane TS Relocation 7/18/2002 7/2003
"* Unit 1/2 Cask Pit Racks 10/23/2002 10/2003
"* Unit 1 Boraflex Remedy 12/2002 12/2003 Turkey Point
"* Unit 3/4 72-Hour Offload 10/21/2002 2/28/2003
"* Unit 3/4 Cask Area Racks 12/2002 12/2003
"* Unit 3/4 Boraflex Remedy Fall 2003 Fall 2004 4
FPL Spent Fuel Storage
- Long-Term Fuel Storage Licensing Actions Amendment Submit Need St. Lucie 0 Unit 2 Rerack (under consideration) 2004 2005 0 TS Program for Spent Fuel Management 2003-2004 2005 0 Long Term Storage Option (by 2015) N/A N/A Turkey Point
"* Crane TS Relocation 2005 2006
"* Long Term Storage Option (by 2010) N/A N/A Seabrook 0 Under review 5
St. Lucie Planning Schedule I
6
Turkey Point Planning Schedule Descnption 2002 2003 2004 2005 Cask Area Rack _ _
(OD)
____ -. FLA Submttal NRC Approval hplermntation License Amendment .... .. cc:,..
_U3J4 L_3L_ L2/U1 Rack Installation al
___ __ _ _ __ ___ LL
Review D_*.
72-Hr Offload PLA_ _C, ,'11 t- - - -
7
St. Lucie Cask Pits Unit 1 Unit 2 half-height steel wall full-height wall /Ikeyway submerged pit submerged pit 8
Turkey Point Cask Area Racks (typical) 9
A' -..-
Cask Pit Rack Projects e Cask Pit Rack Common Objectives
- Extend storage capacity
- Region 1 Cask Pit Rack Objectives (Units 1, 3, 4)
- Load reactive fuel in Region 1 cask pit rack
"° Reduce Boraflex rack degradation
"* Reduce Boraflex rack holddown requirements
- Enhance effectiveness of Boraflex remedies
- Region 2 Cask Pit Rack Objectives (Unit 2)
- Maximize storage capacity
- Facilitates potential pool rerack project 10
Cask Pit Racks 12'-0 044) NON FROM CUETOMER'S ING 3 5/8"NDON.(TYP.)-i L
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/ II LI WOLLS CASKPIT RACKLAYOJT 10 x 12 rack (Unit 1) Rack platform (St. Lucie) 11
Cask Pit Racks
° Common Design Features
- Standard Holtec free-standing rack design
- BoralTM neutron absorber
- Stainless steel structure and sheathing
- 4 adjustable pedestals
- Rack height same as existing racks Point lift rig 12
Cask Pit Racks
- St. Lucie Unique Design Features
- Unit 2 is Region 2 design
- Rack platforms to raise rack level
- Installed with single-failure-proof crane
. Turkey Point Unique Design Features
- Asymmetrical cell design
- Installed with non-single-failure-proof crane 13
Cask Pit Racks
- Affected Technical Specifications - Section 5.6.1 Fuel Storage Criticality
"* Add description of cask pit racks
"* Unit 1 add description of Boral neutron poison
"* Unit 2 add burnup curve for Region 2 cask area rack
"* Unit 3/4 change reference for uncertainty methods
- Section 5.6.3 Fuel Storage Capacity
- Increased spent fuel pool capacity with cask pit rack 14
Cask Pit Racks o Cask Pit Rack Licensing Issues
-Categorical exclusion per 10 CFR 51.22(c)(9) e Environmental Assessments provided 15
Cask Pit Racks o Analyses Performed
- Criticality
- Thermal-Hydraulics
- Structural Integrity
- Radiological
- Heavy Loads Handling
- Holtec International is rack vendor
- Performed many re-rack/rack additions
- NRC accepted methodologies & codes 16
Cask Pit Racks
- Criticality Analysis - Common
- Experienced vendor (Holtec International)
- Acceptance criteria per 10 CFR 50.68
- Previously-accepted codes, uncertainty methods
- Explicit 3D analysis of fuel/rack geometry using MCNP4a
- Fuel burnup isotopics calculated using CASMO-4 17
Cask Pit Racks
- Criticality Analysis - St. Lucie Unique
- Cask pit racks do not require soluble boron credit
- No criticality interface with existing racks 9 cask pit walls decouple cask pit from spent fuel pool
- Unit 2 Region 2 rack has burnup requirements 18
Cask Pit Racks Thermal-Hydraulic Analysis - Common
- Local analysis .- -
- Limiting configuration
- Design basis fuel load
-Outage-specific analyses
-Minimal increase in heat load
-Margin to boiling - D computational fluid dynamics (FLUENT) 19
Cask Pit Racks
- Unit 2 Thermal-Hydraulic Effects
- Limiting configuration - keyway
- Fuel cooled 18 mos. 3.°,,.0 3.60e*02
- 1OF temp rise
- Previously accepted 9 69e.o*
3.58e+02 3.68e.02 3 57e+02 3.570+02 3.56e+02 1Y 3.56e+02 20
Cask Pit Racks
- TH Analysis - St. Lucie Unique
- Single active failure applied per Standard Review Plan
- Bulk TH analysis used bounding system parameters
- Racks on platforms
- Isolated cask pits
- TH Analysis - Turkey Point Unique
- Bulk TH analysis - simple configuration
- Bulk TH analysis same as 72-hr PLA 9 Realistic heat exchanger performance 21
Cask Pit Racks
- Heavy Loads Handling - Common
- Initial installation with Holtec assistance
- Installed with cask handling crane
- Rack drop bounded by cask drop event 22
Cask Pit Racks
- Heavy Loads Handling - St. Lucie Unique
- Single failure proof cranes
- Cask pit walls protect adjacent racks
- Heavy Loads Handling - Turkey Point Unique
- Non-single-failure proof cranes
- Vacate fuel from cells under rack's shadow
-TS LCO 3.9.12 applies: 1525-hour decay time 23
Cask Pit Racks
- Implementation at other plants
-Waterford 3 (approved 7/1998)
"* Cask pit rack for discharged fuel
"*Transfer canal racks (licensed contingency)
- Kewaunee (approved 1/2001)
- Transfer canal racks for old fuel
- All from same vendor (Holtec) 24
Cask Pit Racks
- Summary
- Comprehensive analyses per guidance
- Previously-approved methods, precedent
- One-year review schedules
- FPL organization to support questions
° Questions / Followup Items 25
St. Lucie Boraflex Remedy
Background
- Gamma radiation-induced Boraflex degradation
- Potential loss of reactivity hold-down
- Next Boraflex Test
- 2004 Turkey Point o 2005 St. Lucie Unit 1
- Licensing Objective
- TS Program for spent fuel management 26
St. Lucie Unit 1 Boraflex Remedy P- oraf lex Testin Commitment to 5-year blackness tests
- 2000 blackness test results acceptable
- Next blackness test commitment 2005
- Expensive, burdensome
- License
- Areal Renewal Boraflex Test Commitment Density (BADGER) test by 2016
- No change to License Renewal commitment 27
St. Lucie Unit 1 Boraflex Remedy Boraflex Remedy Objectives
- Obviate Boraflex credit and Boraflex testing
- No loss of storage capacity (no water-holes)
- No new poison inserts
- Cost-effective
- Margin for spent fuel discharge contingencies
- Use Boral Cask Pit Rack for most reactive fuel
- Credit for burnup, control rods, decay 28
St. Lucie Unit 1 Boraflex Remedy
- Soluble
- Most Boron Credit - Design reactive, fresh fuel in cask pit rack
-Checkerboard loading hi/lo reactivity fuel 29
.,," -" " b St. Lucie Unit 1 Boraflex Remedy ALLOWED ALLOWED CHECKERBOARD LOADING REGION 1-TO-REGION 1 Region I Patterns PATTERNS (See Notes 1 and 2) RACK ALIGNMENTS (see Note 3)
"* For most reactive fuel "A" I-qlL1 Patternm 1--I I]
" 'Rack interface alignments OR Minimum Bumup (GWd/MTU)
Fuel Cooling Coefficients for Initial Enrichment Type Time WW~IW A B C 1.9 w/6 2.5 w/o 3.0 w/o 3.8 w/o 1 0 years 0.00 9.31 -24.39 0.00 0.00 3.54 10.99 2 0 years 0.00 10.51 -22.35 0.00 3.93 9.18 17.59 OR 3 0 years 0.00 10.97 -14.71 6.13 12.72 18.20 26.98 0 years -0.41 17.00 -21.39 9.43 18.55 25.92 37.29 12 years -0.54 16.22 -20.63 8.24 16.55 23.17 33.21 15 years -0.53 15.86 -20.07 8.15 16.27 22.74 32.54 20 years -0.46 15.11 -18.80 8.25 16.10 22.39 31.98 0 years -0.74 17.49 -19.72 10.84 19.38 26.09 36.06 5 .4 1 FTr1 -A
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.'A 7n YGAP BETWEEN ADJACENT RACKS 30
- C St. Lucie Unit 1 Boraflex Remedy ALLOWED Region 2 Patterns CHECKERBOARD LOADING PATTERNS (See Notes I and 2)
RACK INTERFACE RESTRICTIONS For less reactive fuel OR OR No rack interface alignments Pattern "C" Pattem "D" Pattern "E" Reactive fuel on periphery
- credits neutron leakage ALLOWED SPECIAL ARRANGEMENTS:
Fresh fuel loading pattern Wall Interior rack cells Up to four Fresh Fuel Assemblies in Pattern "C"or Pattern "E"racks
,ny
° for contingency ittern F2FN10F
- F FS (See Note 3) Mn = FRESH FUEL ASSEMBLY F-j= EMPTY CELL (See Note 4) 31
St. Lucie Unit 1 Boraflex Remedy 1* Y 7 7 7 7 C
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Soluble Boron Credit A A A A P A P Fuel checkerboard (hi/Io reactivity) A A A A P A P Non-fissile storage baskets as water hole A P P Fuel reconstitution in Region 2 P A P Credit for: A IV Decay time A A P A P Control rods A P A P Other inserts (stainless) IA Other inserts (borated stainless) P Other inserts (borated aluminum) P Axial blankets P Erbia/Gadolinia in fresh assemblies P A IFBA A A Radial neutron leakage in periphery A A P A P TS Program_ _ __ P __
A - Approved P-Proposed 32
- 'I t -
St. Lucie Unit 1 Boraflex Remedy Other Tech Spec Changes
- Change criticality criterion per 10 CFR 50.68 e Currently Keff < 0.95 in unborated water
- Upgrade pool boron concentration to an LCO
- Add a 7-day boron concentration surveillance
- Remove description of Boraflex (and Boral) o Consistent with Improved Standard Tech Specs 33
St. Lucie Unit 1 Boraflex Remedy Surporting Evaluations
- By Holtec International
"* Criticality
"* Thermal-Hydraulic
"* Seismic
"* Radiological
- By FPL
"* Boron Dilution Analysis
"* Environmental Assessment for occupational dose 34
StL Lucie Unit 1 Boraflex Remedy Criticality Analysis
- Experienced vendor (Holtec International)
- Acceptance criteria per 10 CFR 50.68
- Explicit 3D analysis of fuel/rack geometry using MCNP4a
- Credit for control rods, burnup, decay, axial blankets, radial neutron leakage on periphery
"*Axial burnup for blanketed/unblanketed fuel treated separately
"* Control rod depletion evaluated, insignificant
"*Fuel burnup isotopics calculated using CASMO-4
- Reasonable levels of soluble boron credit (500 ppm)
- Previously-accepted codes, uncertainty methods 35
St. Lucie Unit 1 Boraflex Remedy Criticality Analysis - Boron Dilution Event
- Inadvertent dilution to 500 ppm (0.95 Keff) found not to be a credible event
"* TS boron concentration 1720 ppm
"* Normal boron concentration 2000 - 2400 ppm
"*Ample time to identify & respond (45 hours5.208333e-4 days <br />0.0125 hours <br />7.440476e-5 weeks <br />1.71225e-5 months <br />) to prevent dilution to 500 ppm 36
Boraflex Remedy
- Benefits of a TS Program for spent fuel pool
- Compliance with 50.68 criticality criteria (TS)
- Controlled under 50.59
- Flexibility for future contingencies 37
Boraflex Remedy Summary
- Comprehensive analyses per guidance
- Previously-approved methods, precedent
- No new inserts for St. Lucie
- One-year review schedule
- Potential for future TS Program for fuel storage
- FPL organization to support questions
- Questions / Followup Items 38
FPL Spent Fuel Storage
'Treatment of Control Rods (CEAs)
- Considered only in Pattern D
- Credited non-lead bank CEAs only - fully w/d at power
- Used initial B-10 loading
- Characteristics verified during LPPT
- Lifetime based on mechanical issues - not depletion
- Considered manufacturing tolerances
- Neglected Ag-In-Cd slug 46
FPL Spent Fuel Storage
- Sensitivity Stud
-30% less B-1i0 in bottom 40" of each CEA finger
- Ap -90 pem
-Insignificant effect 47
St. Lucie Unit 1 Boraflex Remedy
- Consideration of Axial Effects
- Used 3-D MCNP model for criticality calculations
- 10 Nodes w/more detail at rod ends
- Unit 1 SFP contains fuel with & w/o axial blankets
- Natural & enriched axial blankets
- Different enrichment range for each type fuel
- Separate axial burnup distributions
" Fuel w/o axial blankets - used Holtec standard
"* Profiles selected for blanketed fuel minimized end nodes' burnup
"* Enriched shapes used for natural blanket fuel
- Uniform shapes used at low burnup when shown to be more limiting
- Effects of different axial distributions in adjacent fuel