ML101940524

2010 June 30 NRC Technical Meeting

ML101940524
Person / Time
Site:	Crystal River
Issue date:	06/30/2010
From:	Progress Energy Florida
To:	Office of Nuclear Reactor Regulation
paige, Jason, NRR/DORL,301-415-5888
References
Download: ML101940524 (77)

Text

Crystal River Unit #3 Containment Investigation and Repair June 30, 2010

2

• CR3 Containment Design Features Overview

• SGR Opening Sequence & Identification of Delamination

• Root Cause Analysis Results

• Repair Approach

• Repair Activities to Date

• Design Basis Analysis & 50.59 Approach

• Remaining Repair & Validation Activities

• Post-Modification Testing

• Other Topics

• Summary and Questions Agenda

3 CRYSTAL RIVER UNIT 3 DESIGN FEATURES OVERVIEW 3

4 Dimension Value Containment Outside Dimension (OD) 137 ft 0.75 in Dome Thickness 36 in Basemat Thickness 12 ft 6 in Liner Thickness 0.375 in Wall Thickness 42 in Buttress Wall Thickness 70 in Vertical & Hoop Conduit OD 5.25 in

1. of Vertical Tendons 144

1. of Tendon Hoops 94

1. of Tendons per Hoop 3

1. of Prestressed Dome Tendons 123 CR3 Containment Dimensions

5 1

2 3

6 5

4 Plan View Buttress #

(typical)

SGR Opening Seawater Auxiliary Bldg Turbine Bldg Intermediate Bldg Control Complex Heater Bay Bldg Fuel Transfer Bldg Fuel Pool Aux Bldg EDG Bldg

6 SGR OPENING SEQUENCE &

IDENTIFICATION OF DELAMINATION 6

7 Steam Generator Replacement (SGR) Opening (between Buttresses 3 and 4)

SGR Opening Dimensions

@ Liner 23 6 x 24 9

@ Concrete Opening 25 0 x 27 0

8 Steam Generator Replacement (SGR) Opening Hydro-Excavation

9 Concrete & Liner Removal Sequence 1

2

10 Concrete & Liner Removal Sequence (continued) 3 4

11 Delamination Close-up

12 Location of the Delamination Note - Tendon depiction is for illustrative purposes and is not an exact scale

13 Buttress # 3 Buttress # 4 Equipment Hatch area (tendons continue below)

SGR Opening Removed Tendon Energized Tendon Buttress (typical)

Tendon Pattern Tendon Pattern at Time of Cutting SGR Opening CL CL

14 ROOT CAUSE ANALYSIS RESULTS

15

• Comprehensive Team Commissioned

• Progress Energy personnel - expertise across fleet

• Industry peers (Exelon, Southern Company, SCE&G)

• External expertise:

• Performance Improvement International (PII)

• MPR Associates

• AREVA

• Worley Parsons

• Wiss, Janney, Elstner Associates (WJE)

• Construction Technology Laboratories (CTL)

• Numerous PhD's (11) with expertise in root cause investigation techniques, nuclear engineering, nuclear operations & maintenance, material science & testing, concrete standards & construction, concrete testing, concrete creep, concrete fracture, human performance, process analysis, containment analysis, reliability and computer modeling Root Cause Analysis (RCA)

Investigation & Design Basis Team

16

• Condition Assessment & Laboratory Testing

• NDT - Construction Technology Laboratories (CTL)

• Labs - MacTec, Soil & Materials Engineers (S&ME)

• Other Field Data - Sensing Systems, Inc; Core Visual Inspection Services (Core VIS), Nuclear Inspection & Consulting, Inc; Precision Surveillance; Gulf West Surveying Inc; AREVA

• Non-Destructive Testing (NDT) of Containment Wall Surfaces

• Use of Impulse Response (IR) Method and Ground Penetrating Radar (GPR)

• Over 8,000 IR data points taken

• Comprehensive on all accessible areas Root Cause Analysis Condition Assessment

17

• Visual Inspections

• Delamination cracks at SGR opening

• Fragments from concrete removal process

• Containment external surfaces

• Concrete Core Bores

• Over 150 core bores performed

• Ranged from 1 to 8 diameter, 6 to 32 long

• Validated IR data, along with boroscopic inspections

• Laboratory testing Root Cause Analysis Condition Assessment (continued)

18

• Concrete Core Laboratory Analyses

• Petrographic Examination

• Modulus of Elasticity and Poissons Ratio

• Density, Absorption, and Voids

• Compressive Strength, Splitting Tensile Strength, and Direct Tensile Strength

• Fracture Energy

• Accelerated Creep Test

• Accelerated Alkali Silica Reaction (ASR) Test

• Chemistry and Contamination Test

• Scanning Electron Microscope (SEM) Examination of Micro-Cracking Root Cause Analysis Condition Assessment (continued)

19 R

T V

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AA Z

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H Pour 3 Pour 4 Pour 5 Pour 6 Pour 7 Pour 8 Pour 9 Pour 10 Pour 11 Pour 12 Pour 13 Pour 14 Pour 15 Pour 16 Pour 1 Pour 2

- - - - - - - - - - - EL 240

- - - - - - - - - - - EL 250

- - - - - - - - - - - EL 230

- - - - - - - - - - - EL 220

- - - - - - - - - - - EL 210

- - - - - - - - - - - EL 200

- - - - - - - - - - - EL 190

- - - - - - - - - - - EL 180

- - - - - - - - - - - EL 170

- - - - - - - - - - - EL 160

- - - - - - - - - - - EL 150

- - - - - - - - - - - EL 140

- - - - - - - - - - - EL 130

- - - - - - - - - - - EL 120

- - - - - - - - - - - EL 110

- - - - - - - - - - - EL 100

- - - - - - - - - - - EL 90 Buttress #2 Buttress #3 Buttress #4 CL CL CL CL Containment Unfolded - Buttress 2 to 5 Mosaic IR Overlay scale is approximate Buttress #5 1

2 3

6 5

4 CL Aux Bldg Roof EL 167 8 Intermediate Bldg Roof EL 149 0 SGR Opening Equipment Hatch A

B C

D F

G I

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Z AB AD AC A

B C

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AA AB AC AE AF AG SGR Opening Y

10 x 60 @ EL 93 13 x 42 @ EL 93 10x 16 Actual IR scan output data:

Blue = no delamination Yellow= transition Red = delaminated Drawing scale is not exact EL 119 8 x 8 22 x 24 6 x 12 6 x 36 @ EL 164 EL 143 8 x18 14 x

8 IR scans completed with no delamination Blue = no delamination Conclusion - IR scans with confirmation core bores identified delamination only in the Buttress 3-4 span above the Equipment Hatch, as shown in red above

20 14 x 34 10 x60 Pour 3 Pour 4 Pour 5 Pour 6 Pour 7 Pour 8 Pour 9 Pour 10 Pour 11 Pour 12 Pour 13 Pour 14 Pour 15 Pour 16 Pour 1 Pour 2

- - - - - - - - - - - EL 240

- - - - - - - - - - - EL 250

- - - - - - - - - - - EL 230

- - - - - - - - - - - EL 220

- - - - - - - - - - - EL 210

- - - - - - - - - - - EL 200

- - - - - - - - - - - EL 190

- - - - - - - - - - - EL 180

- - - - - - - - - - - EL 170

- - - - - - - - - - - EL 160

- - - - - - - - - - - EL 150

- - - - - - - - - - - EL 140

- - - - - - - - - - - EL 130

- - - - - - - - - - - EL 120

- - - - - - - - - - - EL 110

- - - - - - - - - - - EL 100

- - - - - - - - - - - EL 90 Buttress #5 Buttress #6 Buttress #1 CL CL CL CL Buttress #2 Intermediate Bldg Roof EL 149 0 Fuel Transfer Bldg Roof @ EL 200 4 Intermediate Bldg Roof EL 149 0 B

C D

F G

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R Q

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2 3

6 5

4 CL Q

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12 x 9 EL 160 EL 143 11 x 7

Actual IR scan output data:

Blue = no delamination Yellow= transition Red = delaminated Drawing scale is not exact EL 119 7 x 10 4 x 8 4 x 26 EL 182 38 x

12 20 x

9 EL 119 EL 95 EL 95 20 x12 16 x

8 8

x 8 IR scans completed with no delamination Blue = no delamination Containment Unfolded - Buttress 5 to 2 Conclusion - No delamination identified in these Buttress spans

21 Core Borings Conclusion - Physical observation of core boring has validated the delamination boundary, as accurately predicted by IR.

22 Buttress # 3 Buttress # 4 Equipment Hatch area (tendons continue below)

Buttress (typical)

Tendon Pattern CL CL Removed Tendon Energized Tendon Tendon Pattern at Time of Cutting SGR Opening SGR Opening Showing boundary of delamination

23 SGR Opening Showing Delamination Boundary SGR Opening Dimensions

@ Liner 23 6 x 24 9

@ Concrete Opening 25 0 x 27 0 Yellow line denotes boundary of delamination

24

• 75 potential Failure Modes considered

• Grouped into 9 categories:

• Containment Design & Analysis

• Concrete Construction

• Use of Concrete Materials

• Shrinkage, Creep and Settlement

• Chemically or Environmentally Induced Distress

• Concrete - Tendon - Liner Interactions

• SGR Containment Cutting

• Operational Events

• External Events Root Cause Analysis Failure Modes

25

• 67 Failure Modes were refuted by PII

• Remaining 8 Failure Modes were combined for Root Cause Analysis (with 3D Fracture Analysis and Various Special Tests) to determine their significance

• Failure Mode categories refuted in whole:

• Concrete Shrinkage, Creep, & Settlement

• Chemical or Environmentally Induced Distress

• Concrete - Tendon - Liner Interactions

• Operational Events

• External Events Root Cause Analysis Failure Modes (continued)

26

• Existing industry analysis techniques predicted acceptable margin to delamination at CR3

• Investigation required new tools of progressively increasing complexity

• NASTRAN

• Linear-elastic model

• Determined local conditions for input to Abaqus 3D

• Abaqus 3D (180° model)

• Evaluated local conditions and determined if damage resulted Root Cause Analysis Finite Element Analysis (FEA) Modeling Tools

27

• Final FEA model uses Abaqus Global Model

• 360° Supermodel

• Visco-elastic / non-linear model

• Model includes individual tendons, rebar, liner, etc

• Sub-models provide higher resolution of localized behavior Root Cause Analysis Finite Element Analysis Modeling Tools (continued)

28

• Failure Mode 1.1 - Vertical and Hoop Stress

• Failure Mode 1.2 - Radial Tensile Stresses / Radial Reinforcement

• Failure Mode 1.15 - Design Analysis Methods for Local Stress Concentration Factors Root Cause Analysis Group 1 Failure Modes (FMs): Containment Design CR3 Containment design features are acceptable for normal and emergency operations.

The following failure modes apply to the specific evolution of creating an SGR Opening at CR3.

29

• Failure Mode 2.12 - Strength Properties

• Failure Mode 3.4 - Aggregates Root Cause Analysis Groups 2 & 3 FMs: Concrete Construction / Use of Concrete Materials CR3 Containment concrete construction and materials meet design requirements, and are acceptable for normal and emergency operations.

The following failure modes apply to the specific evolution of creating an SGR Opening at CR3.

30

• Failure Modes 7.3 & 7.4 - De-tensioning Scope and Sequence (Root Cause)

• The number and order of de-tensioned tendons resulted in redistribution of stresses in the containment wall that exceeded tensile capacity, initiating the delamination

• Failure Mode 7.5 - Added Stress Due to Removing Concrete at the Opening

• Removal of concrete increased the stress in the remaining concrete, contributing to the final extent of delamination Root Cause Analysis Group 7 FMs: SGR Containment Cutting Activities The following failure modes apply to the specific evolution of creating an SGR Opening at CR3.

31 Root Cause Analysis Failure Mode Timeline 31

32

• Root cause: De-tensioning scope and sequence resulted in redistribution of stresses that exceeded tensile capacity

• Could not have been predicted based on existing information and models at that time

Conclusion:

Delamination occurred as a result of outage activities to create an opening for steam generator replacement Root Cause Analysis Summary

33 REPAIR APPROACH

34

• Use-as-Is - Rejected

• Anchorage Only - Rejected

• Cementitious Grout - Rejected

• Epoxy Resin - Rejected

• Delamination Removal and Concrete Replacement -

Selected Repair Approach Alternatives Considered

35 Repair Approach Engineering & Field Work Flow De-tension Additional Tendons Implement Crack Arrest Strategy Delamination Removal Re-tensioning

& Post-Repair Testing Phase 1 Modification Crack Arrest RCA Failure Modes Analysis Cross Check Root Cause Analysis Tech Report Complete MPR Calc on Tendon

1. &Sequence RCA Failure Modes Analysis Cross Check Phase 4 Modification Concrete Placement Phase 5 Modification Re-Tensioning Concrete Placement SGT Engineering &

Construction Input (Permanent Repair)

Permanent Repair SGT Engineering &

Construction Input (Repair Preparations)

PII Abaqus Analysis of MPR Tendon

1. &Sequence

Indicates Completed Task

MPR 3D Finite Element Analysis Rebar Installation NDT Examinations (IR & Boroscopic)

Phase 3 Modification Concrete Removal Phase 2 Modification De-tensioning

PII Abaqus Analysis of Re-tension Sequence

36 REPAIR ACTIVITIES TO DATE DE-TENSIONING SCOPE & SEQUENCE

37

• MPR analysis of de-tensioning scope and sequence

• Analysis completed to ensure that restored concrete can be prestressed to meet design requirements

• Stress analysis for the construction evolution

• PII cross reviews using RCA insights/models

• Abaqus model to ensure no delamination in other areas during expanded de-tensioning scope

• Final Scope / Sequence (Option 10F)

• 155 Horizontals (17 already de-tensioned as part of SGR)

• 64 Verticals (10 already de-tensioned as part of SGR)

Repair Tendon De-tensioning Sequence & Scope Refinement

38 Repair Tendon De-tensioning Option 10 F Results - Limiting Stress Check at Panel 2 - 3 125 psi

39

• Total of 11 De-tensioning Passes (3 vertical and 8 horizontal)

• 1V (5 Sequences, 10 tendons)

• 1H (7 Sequences, 20 tendons)

• 2V (6 Sequences, 24 tendons)

• 2H (8 Sequences, 18 tendons)

• 3H (14 Sequences, 32 tendons)

• 4H (14 Sequences, 35 tendons)

• 5H (3 Sequences, 7 tendons)

• 6H (4 Sequences, 10 tendons)

• 3V (5 Sequences, 20 tendons)

• 7H (4 Sequences, 10 tendons)

• 8H (3 Sequences, 6 tendons)

Repair Tendon De-tensioning Final Scope & Sequence - Option 10 F

40 REPAIR ACTIVITIES TO DATE DELAMINATION REMOVAL

41 Delamination Removal Stress Relief Cut

42 Delamination Removal Hydro-Excavation in Progress

43 Delamination Removal Hydro-Excavation Completed

44 Delamination Removal Hydro-Excavation Completed

45 DESIGN BASIS ANALYSIS

& 50.59 APPROACH 45

46 Fission Product Barriers Simplified Schematic Liner Concrete Tendons (horizontal)

Barrier # 1-Cladding Enclosing The Fuel Barrier # 2 - Reactor Vessel & Coolant Piping Barrier # 3 - Containment Liner Tendon depiction is for illustrative purposes and is not an exact scale

47

• All Containment Design Loads Analyzed

• Live, Prestress, Dead Loads

• Wind (110 mph@ 30 increasing to 179 mph @

16610)

• Tornado Wind (300 mph)

• Tornado Pressure (external pressure drop of 3 psig)

• Tornado Missiles

• Seismic (OBE - 0.05 and SSE - 0.10)

• Temperature Loads

• Accident Pressure (LOCA) (55 psig)

• Accident Containment Spray Actuation Pressure (-2.5 psig)/ and (-6.0 psig effect on liner)

Design Basis FSAR Design Loads

48

• Containment Design Features Remain Unchanged

• Prestressed concrete cylindrical wall (shell), shallow dome roof

• Carbon steel liner serves as fission product barrier

• Liner anchored to concrete

• Containment Design Basis Maintained

• Leak-tight structure to contain Design Basis LOCA

• Elastic response to design basis loading to protect liner

• Design loads and combinations based on operating, accident and applicable code requirements

• Load factors applied to provide safety margin Design Basis FSAR Structural Design Parameters

49

• Restoration Area Design Requirements Satisfied

• Designed to ACI 318-63 for all load combinations

• Load capacity of structure defined by strength and deformation limits

• Strength - Upper limit of elastic behavior of effective load carrying materials

• Deformation Limits - Liner strain limit of 0.005 and min yield

• Reinforcement provided for resulting loads on structure

• Utilized concrete compressive strength of 5800 psi based on 90 day strength tests in accordance with ACI 301-66 and ACI 318-63

• Restoration Area Containment Codes (ACI) Satisfied

• ACI 318-63; Building Code Requirements for Reinforced Concrete

• ACI 301-66; Specifications for Structural Concrete Buildings

• ACI 505-54; Specification for the Design and Construction of Reinforced Concrete Chimneys Design Basis FSAR Design Criteria / Codes

50 Design Basis FSAR Allowable Stress

• Restored Containment Allowable Stress Satisfied

• Concrete shell prestressed to eliminate tensile stress due to membrane forces under design loads

• Credit not taken for concrete tensile capacity in the hoop or vertical direction

• Reinforcement added based on cracked section design per ACI 318-63, Part IV-B and ACI 505-54 where required

• Reinforcement added to concrete sections with secondary bending tensile stress to limit crack width, spacing, and depth per ACI 505-54

• Service load combination used working stress design per ACI 318-63, Part IV-A

• Liner strains and stress within limits for all design basis load cases

51

• Analysis uses higher Minimum Required Prestress force

• Horizontal tendon minimum force raised from 1252 kips to 1435 kips

• Vertical tendon minimum force raised from 1149 kips to 1500 kips

• Reset de-tensioned tendons to the original tendon force

• Predicted end of life values remain above new minimum values

• Time dependent losses calculated account for: shrinkage and creep in concrete, and tendon wire relaxation Design Basis Tendon Forces

52

• Higher Minimum Required Prestress force acceptable under 50.59 per NEI 96-07 (endorsed by Regulatory Guide 1.187) guidance as an input to the evaluation methodology

• Minimum Required Prestress force previously removed from Tech Specs, by amendment, and placed under control of 50.59

• No increase in probability of malfunction since ISI Code requirements verify actual force and maintain them above predicted (and minimum) values

• Not a design basis limit for a fission product barrier; the values are not in the FSAR Design Basis Tendon Forces (continued)

53

• Method of Evaluation has not changed

• Finite element analysis (FEA) used in both original design analysis and restoration analysis

• Original Design Analysis

• Method of evaluation is comprised of a combination of analysis techniques

• Kalnins finite differences analysis for uniform shell of revolution

• Finite element analysis used for effect of discontinuities on the shell

• Restoration Analysis

• ANSYS finite element analysis model representing the integrated containment structure used for the effect of the restored area (new discontinuity) on the structure

• Consistent with treatment of SGR construction openings throughout the industry under 50.59 Design Basis Method of Evaluation for the Repair

54

• 50.59 Evaluation Approach

• Widely used finite element analysis tool applied under 10 CFR 50 Appendix B

• Benchmarked against original analysis predicted deformations for Structural Integrity Test with excellent agreement

• Accepted per guidance in NEI 96-07 as conservative or essentially the same Design Basis Method of Analysis 50.59 Approach

55 MPR Design Basis Analysis Finite Element Analysis (FEA) Model Details Mesh at Ring Girder connection Mesh at Foundation connection Composite FEA Model

56

• Hairline cracks identified after delamination removal will be repaired or will meet design and code requirements

• Repaired - In areas above and below the SGR opening, additional concrete was removed to liner

• Repaired - In areas adjacent to SGR opening, localized concrete removal and replacement with concrete is planned

• Other remaining reinforced areas (in Bay 3-4) will meet design and code requirements

• Analysis verifies observed cracks (< 0.005) close and stress redistribution is acceptable Design Basis Restoration Area (Bay 3 - 4) - Addressing Hairline Cracks

57

• Vertical hairline cracking was identified in de-tensioned areas of the containment cylinder outside Bay 3 - 4

• Observed after expanded de-tensioning

• Located near some vertical tendon locations

• Width < 0.010 (as measured at surface and within concrete core holes)

• In all areas of the containment cylinder still tensioned - no observations of vertical hairline cracking during detailed inspections Design Basis Hairline Cracking Outside of Restoration Area

58 Design Basis Hairline Cracking Outside of Restoration Area Buttress 5 - 6 span at elevation ~ 205

59

• Even without hoop tensile capacity in these areas, design basis satisfied

• Concrete behaves as an un-cracked section

• For design loads

• Concrete remains in compression

• For factored load case - 1.5P + Ta

• Concrete has tensile stresses due to liner expansion

• For areas with concrete tensile stresses, prestressed steel and reinforcing steel to be evaluated consistent with ACI 318-63 and ACI 505-54 requirements

• Liner strain and stress acceptance criteria is met for all load cases

• Expected to be acceptable under current licensing basis Design Basis Analysis Hairline Cracking Outside Restoration Area - Design/50.59 Approach

60

• ASME Section III Division 2, Article CC-6000, Structural Integrity Test (SIT) of Concrete Containments fully anticipates that cracks will exist in containments prior to the SIT

• For the performance of a Structural Integrity Test

• Article CC-6225 only requires crack measuring devices to be capable of measuring a minimum width of 0.005

• Article CC-6350 only requires mapping of cracks that exceed 0.010

• Article CC-6530 requires that a summary and discussion of crack measurement be included in the Test Report Design Basis Hairline Cracking Outside Restoration Area - Other Considerations

61

• Stress Reversal - Initial Tensioning to De-tensioning

• After initial tensioning - the steel liner, reinforcement and tendon conduits increased in compressive elastic strain due to concrete creep

• After de-tensioning - the steel liner, reinforcement and tendon conduit elastic strains reversed, but the concrete did not due to creep

• Result was tensile stress in the concrete at the vertical tendons that exceeded tensile capacity Design Basis Hairline Cracking Outside Restoration Area - Cause

62

• Updated PII model (Abaqus) analysis supports hairline cracking development

• Model executed both with and without the liner, reinforcement and tendon conduits for the de-tensioning sequence

• Vertical hairline cracks do not develop when these steel components taken out of model

• Contributor

• Portion of volume change in concrete due to concrete shrinkage Design Basis Hairline Cracking Outside Restoration Area - Cause (continued)

63

• Final repair condition expected to be acceptable under 10 CFR 50.59

• FSAR design basis loading conditions will be satisfied

• FSAR design code requirements will be met

• Changes to analysis inputs accepted by 50.59 evaluation

• Analysis consistent with the existing FSAR described Method of Evaluation Summary of 50.59 Approach

64 REMAINING REPAIR &

VALIDATION ACTIVITIES

65 Remaining Repair & Validation Activities Mock-up Testing - Reinforcement Installation

66 Remaining Repair & Validation Activities Mock-up Testing - Soaking

67 Remaining Repair & Validation Activities Instrumentation Installation Strain Gauge installed in the Mock-up

68 Remaining Repair & Validation Activities Instrumentation Installation (continued)

Strain Gauge (see arrows) &

Temperature Monitors installed on the Containment wall

69 Remaining Repair & Validation Activities Concrete Batch Plant 69

70 POST-MODIFICATION TESTING

71

• Integrated Leak Rate Test (ILRT) required per ASME XI code

• For removing / replacing liner in SGR opening

• Plan to perform a Structural Integrity Test (SIT)

• SIT is normally a one-time initial construction structural test

• Test intent: measures structural integrity and deformation at 1.15 Peak Design Pressure (63.3 psig)

• SIT will be followed by ILRT Post Modification Testing Pressure Test

72

• Re-tensioning Monitoring Plans

• Strain gauges during re-tensioning

• Additional visual examinations will be performed after re-tensioning

• Non-destructive testing (Impulse response) will be performed after re-tensioning

• Pressure Test Monitoring Plans

• Strain gauge measurements

• Deformation measurements

• Visual examinations will be performed in conjunction with system pressure test in accordance with ASME XI, Subsection IWL Post Modification Testing Monitoring Plans

73 OTHER TOPICS

74

• Containment Dome Condition Assessment

• Comprehensive IR scans complete

• Core bores performed specifically to verify IR scanning results

• Final assessment of all data being performed by Architect Engineer (AE)

• Outcome will verify design basis continues to be met or will be restored Other Topics Dome

75

• Containment Liner Bulges

• Liner bulges between vertical stiffeners (18 apart)

• Extent of condition bounded by laser scanning and visual inspections

• UT measurements have confirmed no generalized corrosion or liner wall thinning

• Analysis is expected to verify no impact, and continued conformance to liner design requirements Other Topics Liner Bulges

76 Summary 76 Containment original design and construction are acceptable for normal and emergency operations Planned repair approach meets design basis requirements and code requirements The final repair condition is expected to be acceptable under 10 CFR 50.59 Containment will be fully capable of meeting its design safety function upon completion of repairs and testing

77 Questions 77