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 6
I
Turkey Point Planning Schedule 7
Descnption 2002 2003 2004 2005 Cask Area Rack (OD)
-. FLA Submttal NRC Approval hplermntation License Amendment cc:,..
L_3L_
_U3J4 L2/U1 Rack Installation al LL MRA NRC Review Install Boraflex Remedy 4__O
'T__,
BADGER Test Due I
NFC Review D_*.
72-Hr Offload PLA_
_C,
,'11 t-
St. Lucie Cask Pits Unit 1 Unit 2 half-height steel wall submerged pit full-height wall /Ikeyway submerged pit 8
Turkey Point Cask Area Racks (typical) 9
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 A'
Cask Pit Racks 12'-0 044) NON FROM CUETOMER'S ING 3 5/8"NDON. (TYP.)-i I I
=5
=01
- =o =o
==
=5
-,5 I
4 J 1-44-44-44-44-4 L 4 CASK PIT RACK LAYOJT 10 x 12 rack (Unit 1)
Rack platform (St. Lucie) 11 NON (TYP.)
TNI NON.
FR'O CUTOMERS DVG
/
WOLLS II LI L
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
- Soluble boron credit for Keff 0.95 is 500 ppm or less 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 1 Y 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 Renewal Boraflex Test Commitment
- Areal 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 Boron Credit - Design
- Most reactive, fresh fuel in cask pit rack
-Checkerboard loading hi/lo reactivity fuel 29
St. Lucie Unit 1 Boraflex Remedy Region I Patterns
"* For most reactive fuel
" 'Rack interface alignments
-0.74 17.49 10.84 ALLOWED CHECKERBOARD LOADING PATTERNS (See Notes 1 and 2)
Pattern m
1--I I]
"A" I-qlL1 Minimum Bumup (GWd/MTU)
Fuel Cooling Coefficients for Initial Enrichment Type Time 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 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 5
36.06
-19.72 0 years
.4 1
.4 4
- 4.
.4 1
FTr1 -A
.17 Ar
'in AA 17 OJ
.'A 7n 19.38 26.09 ALLOWED REGION 1-TO-REGION 1 RACK ALIGNMENTS (see Note 3)
OR WW~IW OR YGAP BETWEEN ADJACENT RACKS 30
" b
C St. Lucie Unit 1 Boraflex Remedy Region 2 Patterns For less reactive fuel No rack interface alignments Reactive fuel on periphery
- credits neutron leakage Fresh fuel loading pattern
° for contingency ALLOWED CHECKERBOARD LOADING PATTERNS (See Notes I and 2)
OR OR Pattern "C" Pattem "D" Pattern "E" Wall Interior rack (See Note 3)
RACK INTERFACE RESTRICTIONS ALLOWED SPECIAL ARRANGEMENTS:
Up to four Fresh Fuel Assemblies in cells Pattern "C" or Pattern "E" racks
,ny ittern F2FN10F
- F FS Mn = FRESH FUEL ASSEMBLY F-j= EMPTY CELL (See Note 4) 31
St. Lucie Unit 1 Boraflex Remedy Industry Precedent 1*
Y 7
7 7
7 C
V)
-u 0
Ul) c 0 cu C
0 0
5 C')
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Ul) cu (L_
t 0 z 0
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ca 4
0 c 0z Cn cJ a,
-J
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C C,,
o*
a W
-J 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
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