ML020670600

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Transcript of ACRS Combined Thermal-Hydraulic Phenomena/Future Plant Designs: Subcommittee Meeting Open Session, February 13, 2002, Pages 1-327/361-375 (Closed Session Pp 328-360) in Rockville, MD
ML020670600
Person / Time
Site: Arkansas Nuclear Entergy icon.png
Issue date: 02/13/2002
From:
Advisory Committee on Reactor Safeguards
To:
References
NRC-232 ACRST-3186
Download: ML020670600 (153)
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Text

ARKANSAS NUCLEAR ONE, UNIT 2 (ANO-2)

EXTENDED POWER UPRATE (7.5%)

ACRS THERMAL-HYDRAULIC PHENOMENA SUBCOMMITTEE MEETING FEBRUARY 13, 2002 TOM ALEXION, PROJECT MANAGER PROJECT DIRECTORATE IV, SECTION 1 DIVISION OF LICENSING PROJECT MANAGEMENT 1-1

BACKGROUND

  • SG's replaced in fall of 2000 SIncreased mass Increased primary and secondary volumes SIncreased number of tubes STubes made from Alloy 690
  • Increased heat transfer area 1-2

NRC STAFF REVIEW APPROACH

" Farley 5 % power uprate SE (1998)

" Standard Review Plan

" Acceptable codes and methodologies

"*Relied on analysis done for SG replacement

" Requests for Additional Information (RAIs)

" Audits/independent calculations in selected areas 1-3

PRINCIPLE AREAS OF REVIEW

"- NSSS, ACCIDENT ANALYSIS, AND OTHER DESIGN BASIS EVALUATIONS

"* EVALUATION OF SSCs

"* BOP SYSTEMS & RELATED EVALUATIONS

"* HUMAN FACTORS

"*RADIOLOGICAL ANALYSES

"*RISK ASSESSMENT OF POWER UPRATE 1-4

ORDER OF NRR PRESENTATION

" Reactor Systems Review

"*Plant Systems Review

" Mechanical & Civil Engineering Review

" Materials & Chemical Engineering Review

" Radiological Assessment

"*Risk Assessment of Power Uprate 1-5

SUMMARY

OF NRR REVIEW

"- When the Draft SE was issued, the only open items were in the dose area

"- These items have been resolved; the details will be discussed in the presentation by the appropriate review branch

" Therefore, the NRR staff has no open items 1-6

ARKANSAS NUCLEAR ONE, UNIT 2 (ANO-2)

EXTENDED POWER UPRATE (7.5%)

REACTOR SYSTEMS BRANCH (SRXB)

Chu Liang 2-1

SRXB REVIEW AREAS

  • Fuel Performance NSSS Design Transients mLOCA and Non-LOCA Accident Analyses 2-2

SRXB REVIEW PROCESS

" Reviewed Application to Current Licensing Basis

" Verify Plant Modifications meet SRP Acceptance Criteria

" Many Transients and Accidents Previously Reviewed at Uprated Power Levels in Amd. 222, dated 09/29/00 (Steam Generator Replacement)

" Revised Transient and Accident Analyses Reviewed to:

, Assure use of Approved Codes and Methodologies

  • Results meet Acceptance Criteria in SRP 2-3

SRXB REVIEW RESULTS All Transient and Accident Analyses met SRP Acceptance Criteria All Transient and Accident Analyses were Analyzed using Staff Approved Codes and Methodologies All Transient and Accident Analyses Inputs are Conservative and Consistent with TS Limits Fuel meets all Design Requirements and Limits 2-4

ARKANSAS NUCLEAR ONE, UNIT 2 (ANO-2)

EXTENDED POWER UPRATE (7.5%)

PLANT SYSTEMS BRANCH (SPLB)

Dave Cullison 3-1

PLANT SYSTEMS BRANCH

  • Reviewed system design/operation requirements impacted by power uprate to assure agency regulations/guidelines are met under power uprate conditions. Nine NUREG-0800, Standard Review Plan sections used as follows:

6.2.5, SSRP Combustible Gas Control in Containment SRP 9.1.3, Spent Fuel Pool Cooling and Cleanup

PLANT SYSTEMS BRANCH

  • Continuation of SRP sections used:
  • SRP 9.2.6, Condensate Storage Facilities SSRP 10.2, Turbine Generator 10.3, Main Steam Supply SSRP

PLANT SYSTEMS BRANCH BOP Systems Affected or Impacted by Power Uprate No Significant Impact SFuel Pool System Water System SService

  • Ultimate Heat Sink*

SContainment Cooling*

  • Turbine Steam SMain Supply. System Dump SSteam and Bypass System

PLANT SYSTEMS BRANCH BOP Systems Affected or Impacted by Power Uprate

- No Significant Impact (Continued)

P Condensate and Feedwater System Emergency Feedwater System

  • Other BOP Evaluations
  • Containment Response Analysis*

SControl Room Uninhabitability Post-LOCA Hydrogen Generation High Energy Line Break (HELB)*

Protection Program SFire

PLANT SYSTEMS BRANCH Focus BOP Systems

  • Fuel Pool System

- Evaluated administrative controls that ensure current licensing basis maintained

- RAI to provide more information on the impact on the fuel pool cooling system of the increased decay heat in unloaded spent fuel

- Found acceptable

  • Service Water System

- RAI to provide more information on impact of power uprate on system

- Found that no changes to the safety-related portion of the system are required 3-6

PLANT SYSTEMS BRANCH Focus BOP Systems

- RAI to determine adequate feedwater available

- Non-related licensing action to reduce CST Technical Specification levels was withdrawn

- Technical Specification CST levels adequate

- No significant impact on the system's ability to perform its function 3-7

ARKANSAS NUCLEAR ONE, UNIT 2 (ANO-2)

EXTENDED POWER UPRATE (7.5%)

MECHANICAL & CIVIL ENGINEERING BRANCH (EMEB)

Kamal Manoly 4-1

EMEB REVIEW AREAS

  • Components Evaluated Vessel, Internals, Nozzles and CRDMsSReactor Replacement Steam Generators and Nozzles Coolant Pumps, Pressurizer and Nozzles SReactor NSSS and BOP Piping Systems and Supports Safety-Related Valves (MOVs, AOVs, and SRVs) 4-2

EMEB REVIEW AREAS (CONTINUED)

  • Scope of Review Methodology, Loads

, Stresses and Cumulative Usage Factors Acceptance Criteria, Codes and Addenda Functionality and Impact of EPU on GL 89-10 for MOVs, GL 95-07 for Pressure Locking and Thermal Binding, GL 96-06 for Over-pressurization of Piping Segments Penetrating Containment 4-3

EMEB REVIEW AREAS (CONTINUED)

  • Replacement Steam Generators and Nozzles SFinite element analysis of the RCS for design basis loadings using the ANSYS computer code SCalculated stresses and CUFs for the limiting RSG components and supports compared against allowables vibration on the U-bend tubing within SFlow-induced allowable limits (i.e., maximum stability ratio maintained below 0.75 - less than the limit of 1.0, and peak stresses less than material endurance limit) 4-4

EMEB REVIEW AREAS (CONTINUED)

  • NSSS and BOP Piping Systems and Supports

, Finite element analysis performed for revised design loads using Bechtel ME101 Code

  • Calculated stresses compared to ASME Code Section III limits

, CUFs for Class 1 piping calculated based on 60 years and compared to ASME limit of 1.0 4-5

EMEB REVIEW AREAS (CONTINUED)

  • Flow-Induced Vibration of Main Steam Piping SMain steam remains most sensitive system to FIV SWRI study indicated that kinetic energy is driving force behind FIV decreases SFIV as a result of power uprate Piping vibration monitoring during startup, according to OM-3, using hand-held devices and walkdown visual inspection of main steam piping inside and outside containment 4-6

ARKANSAS NUCLEAR ONE, UNIT 2 (ANO-2)

EXTENDED POWER UPRATE (7.5%)

MATERIALS & CHEMICAL ENGINEERING BRANCH (EMCB)

Barry Elliot 5-1

Systems, Components, Analyses and Programs Reviewed for Power Uprate

"*Fuel Pool Purification System

"*Chemical Volume Control System

"*Containment Spray System

"*Leak-Before-Break Analysis

"*Primary & Secondary Water Chemistry Program

"*Flow Assisted Corrosion Program

"*Neutron Fluence & Reactor Vessel Integrity

"*Steam Generator Tube Integrity

"*Alloy 600 Program 5-2

Alloy 600 Program

" Uprate will increase Thot from 604TF to 609TF

" Increase in Thot will not substantially increase PWSCC initiation and growth rates

" Increase in Thot will increase the Susceptibility Ranking of Vessel Head Penetrations (VHPs);

However ANO-2 remains in the moderate range

" Potential for PWSCC to develop in Alloy 600 nozzles will not be significantly effected

"*No change in Alloy 600 and VHP inspection program 5-3

Neutron Fluence / Reactor Vessel Integrity

"*Upper Shelf Energy and RTPTs values meet regulatory screening criteria

"*Pressure-Temperature Limits and Low Temperature Overpressure System Setpoints will be modified for Uprated Conditions - separate application

"*Reactor Vessel meets regulatory requirements 5-4

Steam Generator Integrity

"*Alloy 690 tubes more resistant to Stress Corrosion Cracking than Alloy 600 tubes

"*Degradation of tubes resulting from deposition of copper was eliminated by removing copper from the secondary side

"*Redundancy and analysis of vibrational frequency response of anti-vibration bars minimizes wear

"*RG 1.121 analysis ensures structural integrity

"*No change in tube inspection program 5-5

ARKANSAS NUCLEAR ONE, UNIT 2 (ANO-2)

EXTENDED POWER UPRATE (7.5%)

PROBABILISTIC SAFETY ASSESSMENT BRANCH (SPSB)

Licensing Section - Dose Assessment Michelle Hart 6-1

Dose Assessment Review m Regulatory Requirements 10 CFR Part 100 SGDC 19 m Review Conducted in Accordance with Applicable SRP Sections 6-2

Accidents Analyzed

Seized Rotor MSLB Line Break SFeedwater 6-3

Draft SE Open Items m GDC 19 Review

- SGTR U Reactor Building Mixing for MHA 6-4

GDC 19 Assessement 0 Licensee Developed Action Plan to Address Staff Concerns with Control Room Envelope Unfiltered Inleakage Uncertainty to be Completed Prior to Startup SModifications 0 New Licensing Basis Inleakage Value Based on Tracer Gas Testing U Staff Confirmed Acceptability of Inleakage Assumption for MHA, CEA Ejection, FHA &

SGTR 6-5

SGTR

"- Analysis Was Unavailable for Draft SE

"* Staff Had Concerns with Distribution of Iodine Isotopes for RCS in Analysis

"* Revised Distribution Provided

"* Staff and Licensee in Agreement on Use of Distribution 6-6

Reactor Building Mixing Issue

"* Return Air to Unsprayed Region Assumed Only From Sprayed Region

"* Licensee Provided Clarifying Details of Mixing Model

"* Staff Concerns Resolved

  • Staff Performed Independent Assessment of Reactor Building Concentration Values
  • Found Comparable to Licensee Values 6-7

Dose Results All EAB and LPZ Doses meet Part 100 & within SRP Dose Guidelines All Control Room Doses meet GDC 19 & within SRP Dose Guidelines 6-8

ARKANSAS NUCLEAR ONE, UNIT 2 (ANO-2)

EXTENDED POWER UPRATE (7.5%)

PROBABILISTIC SAFETY ASSESSMENT BRANCH (SPSB)

Safety Program Section - Risk Assessment Donald Harrison 7-1

ANO-2 EPU STAFF RISK ASSESSMENT REVIEW

"* Licensee Submitted Risk Information for Insights and to Ensure No New Vulnerabilities Created

- Internal Events

- External Events

- Shutdown Operations

- PRA Quality

"* Staff SEs on IPEs and IPEEEs

"* Site Review of Fire Analysis and HRA 7-2

ANO-2 EPU OVERALL EPU RISK CONCLUSIONS

  • OVERALL RESULTS 0- Internal Events CDF -2E-5/yr ACDF -3E-6/yr LERF--5E-7/yr ALERF-9E-8/yr 0 External Events (Fires) CDF-IE-4/yr ACDF -2E-5/yr (Vulnerability Analysis) 0 Shutdown Operations Expect Small Impact
  • LICENSE APPLICATION ACCEPTABLE 0, Meets Deterministic Requirements 0 No Changes Identified in Management of Risks 0 No New Vulnerabilities Identified SIdentified Issues Do Not Rebut Presumption of Adequate Protection and Expected Small Risk Increase Does Not Warrant Denial of the License Application 7-3

ARKANSAS NUCLEAR ONE, UNIT 2 (ANO-2)

EXTENDED POWER UPRATE (7.5%)

NRR STAFF CONCLUSION Tom Alexion 8- 1

NRR STAFF CONCLUSION

"*NRR staff performed extensive review

"*No open items

" Application meets applicable regulations

" Acceptable codes and methodologies used

" Reasonable assurance of public health and safety

"*NRR staff recommends approval of power uprate 8-2

Su S.c mit ATnln ee 'n Review of ANO-2 Core Power Uprate Request February 13, 2002

-* Entergy

Introduction I

Rick Lane 1

tEn tergy

I Introduction I

  • Presenters (Entergy) Entergy Support Staff Milton Huff Doyle Adams Mike Krupa Bryan Daiber \ Glenn Ashley Tommy Morrison Rich Swanson Dennis Boyd Dan Spond Dale James Dan Fouts Roger Wilson Jamie GoBell Westinghouse Support Staff Joe Cleary Mehran Golbabai Karl Haslinger Kim Jones Ralph Surman AE Tom Watson 2

I Introduction o Project goals Safely uprate ANO-2 by performing analyses and modifying the plant as required to support 7.5% uprate

-Maintain adequate operating / design margins

- Use accepted methodology One cycle of operation with several modifications tEn tergy 3

  • Project Team

- Entergy staff performed the/NE function that included the system evaluations and modifications to support the uprate

- Utilized some contractor staff augmentation but Entergy engineers had lead oversight tEntergy

  • Project Team NSSS analyses were performed by Westinghouse, formerly Combustion Engineering (CE). CE is the original equipment manufacturer and fuel supplier

- Total engineering effort is approximately 130,000 manhours

  • En tergy
  • Project Overview

- 7.5% Uprate of ANO-2

- Replacement steam generators (RSGs) installed in 2R14 supports increase

- Containment building design pressure increased in 2R14 supports uprate

  • Implementation schedule

- 2R15 Outage, Spring 2002 6

6En tergy

  • Reactor Design Rating

- Original reactor core design = 2815 MWt

- Post 2R1 5 (Uprated) reactor core design =

3026 MWt (7.5 %)

- First request for design re-rate

Entergy
  • Compliance with regulatory requirements

- Submittal prepared using guidelines from:

"* Westinghouse topical WCAP-1 0263, "A Review Plan for Uprating the Licensed Power of a PWR Power Plant"

"*Guidance from GE topical NEDC-31897P-A, "Generic Guidelines for GE BWR Extended Power Uprates" "o SECY-97-042, Section 3, "Power Uprate Review Process" ,l,

"*Farley uprate submittal *En tergy 8

  • Demonstrated compliance with applicable regulations/safety limits

- Analyses Performed

"* Reactor operating conditions, accidents, and transients

"* Radiological consequences

"° Probabilistic risk

"* Programmatic evaluations Aft 9 ý-En tergy

Changes to I

Plant Accommodate Power Uprate Milton Huff 0t 10 'ýýEntergy

  • Site Modification Approach

- All modifications accommodate 7.5% power uprate conditions

- Modifications implemented over four cycles

- Early implementation of modifications provided validation of performance prior to uprate

- Majority of major modifications are installed 11 Entergy

  • Modifications installed to date

- Replacement steam generators

- Condenser

- Moisture separator reheaters

- High pressure turbine

- Low pressure turbines 12:tergy

  • Modifications Installed to date (cont'd)

- Generator rewind

- Hydrogen coolers

- Stator piping

- Containment cooling fan pitch change

- Containment chilled water coils for normal cooling 1tk

ý-Entf) 13

  • Modifications to be installed prior to power uprate (Cycle 16)

- Stator water heat exchanger

-Isophase bus cooling fans

- Heater drain pumps 14 tErgy

  • Setpoint changes

- Feedwater heaters

- Containment uprate approved under previous licensing amendment 15 -- Entergy

Conclusion Balance-of-plant structures, systems and components acceptable for power uprate by either modification or evaluation 16Entergy

I Plant Changes to Power Uprate I Accommodate Bryan Daiber 17 Entergy

  • Fuel Design

- ANO-2 Cycle 16 (First Thermal Uprate Cycle)

  • Standard 16x16 fuel design
  • 177 total assemblies
  • 80 fresh assemblies being added
  • Changing burnable poison
  • Increasing Tcold 2 OF from Cycle 15 tergy
  • Reducing Radial Peaking 18
  • Fuel Design changes

-Change in Integral Burnable Absorber

"* currently using Gadolinia

"*Cycle 16 will use Erbia

-Benefit of Erbia

"* More dilute poison, more evenly distributed

"*Less Adverse Response to transients (Control Element Assembly withdrawal events)

"*Better moderator temperature coefficient control

"*Better power peaking 19 tý LEn tergy

Plant Modifications ho I

  • Comparison to Previous Cycles Parameter Cycle 14 Cycle 15 Cycle 16 Burnable Poison Gadolinia Gadolinia Erbia Reload Batch Size, # 80 68 80 Cycle Length, Effective 557 491 485 Full Power Days (EFPD)

Radial Peaking Factor, 1.56 1.56 1.44 Fr Tcold, F 545 549 551 RCS Flow, % of design 104.5 106.5 106.5 flow

"*En tergy 20

Im Conclusion Fuel Design Verified to be Acceptable at Uprated Power Conditions 21 Entergy

  • BAM Tank Limiting Analysis, Consistent with CEN-366

- Modes 1, 2, 3 and 4 (power operation to Hot Shutdown)

"*Cooldown without letdown

"*Cooldown starts at 26 hours3.009259e-4 days <br />0.00722 hours <br />4.298942e-5 weeks <br />9.893e-6 months <br /> after shutdown coincident with Xenon decay

"*Loss of offsite power assumed

"° Based on End of Cycle (EOC) zero initial boron in RCS

"*Maintain 5% shutdown margin

"* Most negative moderator temperature -k coefficient (MTC) 22ntergy

Mode 5 and 6 (Cold Shutdown & Refueling)

"*Cooldown from 200 'F to 135 'F

"*Maintain 5% shutdown margin

"*BAM Tank minimum required level increased slightly, 31% to 36%

Results

- More Negative MTC Increases Requirements

- Margin Added in Conversion to Indicated Level

- BAM Tank concentrations of 2.5 w/o up to 3.0 w/o removed 23 Entergy

BAM Tank Concentration w I Conclusion BAM Tank Levels and Concentrations are Acceptable 24 17Entergy

"*Reactor Vessel PT Limits

"*October 25, 2001, submittal contained:

- Specimen analysis of the vessel surveillance specimen removed during 2R14 at -15.5 EFPY

- New Technical Specification pressure /

temperature limits out to 32 EFPY.

Includes power uprate conditions.,

25Entergy

"*Fluence Determination

- Methodology described in BAW-2241 P-A, Rev. 1

- Estimated the fluence based on anticipated power uprate conditions

"*Results

- Opens operating space 26 Entergy

Pressure / Temperature Limits ho Conclusion New PT Curves are Acceptable For Power Uprated Conditions 2Etk Et fy 27`

Co piac ithRgultor I e uie et Bryan Daiber 28

--- En tergy

Reqirement

  • Analysis Performed

- Used Approved Methods or Current Methodology

"* Containment, LOCA, Chapter 15 Events

"* New Applications of Approved Methods

- LBLOCA, Boric Acid Precipitation, Offsite Release, and Control Room Dispersion Factors

"* New Methods

- Feedwater Line Break - Credit low level trip on the affected steam generator Aft 29

Entergy

  • Analysis Performed

- Verified Compliance with all Applicable Regulatory Guidance and Acceptance Criteria

-Application of NRC Approved Methods have been Verified to be in Compliance with the Limitations and Constraints 30 t ý-En tergy

Compliance with Regulatory Requ'irements Conclusion Verified Compliance with all Applicable Regulatory Guidance, Acceptance Criteria and SER Limitations and Constraints 31Entergy

  • Balance of Plant

- Reviewed systems for Design Requirements and verified adequate margins

"* Electrical Power - Grid Stability, Main Generator, Transformers, EDGs, and Alternate AC

"* Steam and Power Conversion - Turbine, Main Steam Supply, Water Chemistry, Steam Dump and Bypass System, Condensate and FW, and EFW

"*Auxiliary Systems - SFP, SW, Ultimate Heat Sink, Containment cooling, and SDC

- Implemented Modifications as Necessary to restore margin Af 32 Entergy

- Reviewed systems for Design Requirements and verified adequate margin Reactor Coolant System Chemical and Volume Control System Safety Injection Systems Shutdown Cooling System

- No Modifications Necessary 33 Entergy

Plant Margins

  • Control Systems

- Reviewed systems for Design Requirements and verified adequate margin Pressurizer Pressure Control Pressurizer Level Control Feedwater Control System Steam Dump and Bypass Control System Plant Protection Systems (RPS & ESFAS)

Plant Monitoring Systems (COLSS and CPCs)

- Adjusted Setpoints As Necessary A&

"En tergy 34

  • Containment

- Increased Design Pressure from 54 psig to 59 psig

"*Verified equipment operation

"*Changed pitch on containment fans - require 2 fans

- Integral flow restrictor nozzle

- Installed Containment Spray Actuation Signal (CSAS) to isolate FW and Steam

  • Trip hardened relays
  • Fuel Design

- Erbia Poison 3Entergy 35

Plant Margins Conclusion The Plant was Reviewed and Adequate Margin is Available at Power Uprated Conditions 36 7ý-En tergy

I Review Issues I Bryan Daiber EM

  • En tergy 37

Anticipated Transient Without L Scram (ATWS) I Bryan Daiber 38 z Entergy

  • ATWS Event Response for Uprate Conditions

- ANO-2 complies with the ATWS rule 10CFR50.62 with its Diverse Scram System / Diverse Turbine Trip (DSS / DTT) and Diverse Emergency Feedwater Actuation System (DEFAS)

- Power Uprate did not affect the system design functions ( hardware, operator interface, system logic, etc.)

Entk 39 7ýEntergy

  • ATWS Event Response for Uprate Conditions (con't.)

- DSS /DTT Setpoint Philosophy:

Setpoints and response times coordinate with Plant Protection System (PPS) hi pressurizer pressure setpoint to ensure DSS/DTT does not actuate before PPS. Additionally, DSS/DTT must actuate before lifting pressurizer safeties.

"*Existing setpoints and response times.were maintained for uprate ty 40OEn tergy

  • ATWS Event Response for Uprate Conditions (con't.)

- DEFAS Setpoint Philosophy:

"* Setpoints and response times coordinate with Plant Protection System (PPS) Emergency Feedwater Actuation (EFAS) low SG level actuation function to ensure DEFAS does not actuate before plant protection system (PPS) actuates (i.e., level setpoint < PPS)

"* Existing setpoints and response times were maintained for uprate (Note: Time delay setting changed for SG replacement during 2R14) "'

41 Enntergy

I TW Conclusion ANO-2 Design Regarding ATWS Remains Effective for Uprated Power 4t 42 ýEn tergy

Containment Response Analysis

"*Overview

"* Results 4:Entergy

Overview

  • NRC Approved Methods Used

- Westinghouse - CE Mass/Energy release

- Bechtel COPATTA code used for containment response

  • License Amendment 225 44 " Entergy

Results

"*Limiting Single Failure

- For LOCA - Loss of EDG

- For MSLB - 0% Power, 1 CS Train Failure

"*Limiting Containment Peak Pressure

- 57.7 psig (both MSLB and LOCA) 45 En tfrgy

Containment Conclusion Peak Containment Pressure is Acceptable "46

--- En tergy

"On Rich Swanson 47 Entergy

  • Operations oversight
  • Review of all modifications and evaluations for impact on operation
  • Emergency Operating Procedure impact 48 17ý7Entergy
  • Training

- Simulator changes have been made

-Two crew training cycles

-Crews evaluated on the uprated plant prior to outage

  • Changes have much less impact than SG Replacement 49Entergy
  • Controls and Displays

-Changes minimal or none

"* No physical modifications to control stations

"* No change to format of the Safety Parameter Display System

-Some display ranges will be re-scaled 50 t ý-En tergy

I Operator Training/Impact IN I

  • Procedures

- Emergency, Abnormal and Normal Operating

- No change to type and scope

-No new procedures

  • Emergency Operating Procedures

-No change to type and nature of actions No new actions AI 51 E'-'Entergy

I!p rtrTaiigI p c

  • Power Ascension testing

-Operations involved in development and implementation

-Test Teams designated to perform testing

- Experienced 52 ---- Entergy

  • Power Ascension testing

- Normal testing until 90% of new rating

- Step up @ 2.5% increments

- Walkdowns, Control System checks, verify parameters against design

- All issues will be resolved prior to proceeding 5y "53 'ý---Entergy

2R1 5/Cycle 16 Power Ascension Profile 120 (estimate only) 100 Hry 24-4-4r8 r24-48 Hr 9 24-48 Hr 244 0 7 S 80 68'/

- Turbine Overspeed Testing

- 1 8% Physics Testing

0. 1d 3- 30% Physics Testing t- 68% Physics Testing 5- 90% Walkdowns and Data Collection 40 I r~k - 92.5% Data Collection

- 95% Data Collection 3- 97.5% Data Collection 3- 1 00% Physics and Performance Testing 20 . I 0 - Long Term Tests 0 II-r II I II II II I I

5 I

1 I I I 37 49 61 73 85 97 109 121 133 145 157 169 181 193 205 217 229 241 253 1 13 25 Time(Hrsj

Operator Training/Impact Conclusion The impact of power uprate on Operations training, procedures and response times has been evaluated and and found to be acceptable A t 55---E tergy

IAlo 601 Dale James 56 17Entergy

Alloy 600 1

  • Program currently in place to address cracking of small bore and control element drive mechanism (CEDM) nozzles

Small Bore Nozzles

"* Hot leg nozzles having slightly higher susceptibility to PWSCC, but no change in safety significance

"* GL-88-05 walkdowns conducted each hot shutdown

"* Bare metal examinations of hot leg and PZR nozzles

  • Replace with Alloy 690 material as leakage identified

"* Cracking axially oriented and not safety significant

"* Preventive repairs of hot leg RTDs and pressure taps implemented in Fall 2000 58 ----Entergy

Alloy 600 CEDM Nozzles

  • Preliminary Safety Evaluation performed per Materials Reliability Program (MRP) program document - EPRI MRP Report 48
  • Ranking time reduced from 17.1 EFPY to 14.2 EFPY (t = 0 measured from March 2001)
  • ANO-2 continues to fall within moderate category
  • 100% NDE planned for 2R1 5 Et Lfg 59

Conclusion

  • Vessel head penetration susceptibility still characterized to be in moderate category even with power uprate
  • Programmatic reviews and inspections ensure that Alloy 600 small bore and vessel head penetrations are adequately monitored at ANO A 60

En tergy

Fl[1owv vAceeae Cors n

"* FAG affects carbon steel components in the steam cycle where process temperatures exceed 200 OF

"*Power uprate results in increased flow rates in certain systems

"*Power uprate effects evaluated using CHECKWORKS

"*All susceptible systems included in study 61trk 61 t----En tergy

FlowAccelrate Corosio

  • Most recent inspection results included as baseline
  • Worst case operating parameters utilized
  • Results indicated minimal impact on predicted FAC wear rates
  • Piping systems impacted the greatest by power uprate will continue to be monitored to detect any deviation from predicted wear rates _

62 tE rgy

Conclusion

"* Evaluation of power uprate conditions indicate minimal impact on FAG wear rates

"* Monitoring and replacement activities will continue to assure potential for FAG failures are minimized 63 tergy

  • Replacement steam generators installed in Fall 2000 specifically designed and analyzed for uprate conditions
  • Significant design enhancements incorporated to address previous damage mechanisms

- Alloy 690 TT

- Increased heat transfer surface area

- Full depth hydraulic expansion

- Stainless steel broached tube support plates

- Sludge collector

- Improved u-bend support t----En tergy 64

  • 100% eddy current inspection to be performed during upcoming refueling in accordance with EPRI guidelines 65:----En tergy

Conclusion

C-.

3

.. 1 ( I 0

0 m

CD

ýý 10

PipngAn ysI Scope - initiating changes & boundaries

- Replacement steam generator (RSG)

- Power uprate

- Piping inside containment

- Piping outside containment 68Entergy

PipingAn lsi

  • Methodology

- Piping inside containment

"* validated original design margins

"* rigorous reanalysis at power uprated conditions

"* seismic, deadweight, containment pressure

"* LOCA loads (branch line pipe breaks, asymmetric compartment pressurization)

"*revised design transients 69

`Entergy

  • Methodology

- Piping inside containment

"* increased cycles for license renewal

"* maintained or improved original code of record and analytical techniques

"* satisfy code stress and fatigue usage requirements 7y 70 Entergy

  • Methodology Piping outside containment

"*pressure & temperature changes were evaluated relative to the analysis of record using scaling factors for stress and support/nozzle loads

"*dynamic analysis

"*HELB/MELB, missile hazards, FAC, thermal movement, flaw evaluations, expanlin joints 71 En tergy

Conclusion

"* Few modifications required

- spring load changes to reduce nozzle loads

-vibration hardening modifications

"* Comprehensive review and analysis

"* Piping remains qualified for changes 72 t En tergy

I ECCS Analysis Bryan Daiber AEg

'ýEn tergy 73

- Methodology

- Assumptions

- Acceptance Criteria

- Results 74 '-En tergy

  • Methodology

- Cycle 16

  • New Approved Methodology Applied
  • 1999 EM (evaluation model)
  • CENPD-1 32, Supplement 4-P, Revision 1 "Calculative Methods for the CE Nuclear Power Large Break LOCA Evaluation Model", August 2000

-Cycle 15

° 1985 EM ..

75Entergy

  • Assumptions

"* Power level 3087 MWt vs. 2900 MWt

"* Increased LHR 13.7 kW/ft vs. 13.5 kW/ft

"*Increased Range of Safety Injection Tank (SIT) pressure

- 500/700 psia vs. 550/650 psia

"* Increased Range of SIT Volume

- 1000/1600 ft3 vs. 1350/1600 ft3 76 tEEn tergy

LBLOCA IN I o Results Break Size Peak Cladding Maximum Cladding ITemperature (°F) Oxidation (%)

1.0 DEG/PD 2080 6.2 0.8 DEG/PD 2081 6.3 0.6 DEG/PD 2108 6.9 0.4 DEG/PD 2154 7.8 0.3 DEG/PD 2112 6.9 DEG/PD - Double Ended Guillotine Pump Discharge A AEt 17Entergy 77

LBLOCA IN

  • Comparison to Cycle 15 Parameter Criterion Cycle 15 Cycle 16 Results Results Break Size DEG/PD 0.6 0.4 Peak Cladding Temp, 'F
  • 2200 2029 2154 Max Clad Oxidation, % *17 5.4 7.8 Max Core Wide, Oxidation % <1 0.99 0.99 Coolable Geometry Yes Yes Yes E t

':----Entergy 78

  • Methodology

"* Used Current Analysis of Record Methodology

"*S2M

"° CENPD-1 37, Supplement 2-P-A "Calculative Methods for the ABB CE Small Break LOCA Evaluation Model", April 1998.

79 Entergy

  • Assumptions

"* Power level 3087 MWt vs. 2900 MWt

"* Increased LHR 13.7 kW/ft vs. 13.5 kW/ft

"* Increased Range of SIT pressure

- 500 psia vs. 550 psia

"* High Pressure Safety Injection (HPSI) flow unchanged 80

---Enntergy

SBLOCA I

o Results Break Size Peak Cladding Maximum Cladding Maximum Core Temperature ('F) Oxidation (%) Wide Cladding Oxidation (%)

0.03 ft2 PD 1842 3.3 <0.43 0.04 ft2/PD 2066 10.8 <0.67 0.05 ft2/PD 1882 10.6 <0.63 0.04 ft 2/PD (1) 2090 12.5 0.73 PD - Pump Discharge (1) Limiting break size PCT was corrected due to coding error.

81 t ý--En tergy

  • Comparison to Cycle_15 Parameter Criterion Cycle 15 Cycle 16 Results Results Break Size ftz/PD 0.04 0.04 Peak Cladding Temp, F *<2200 1905(1 2066(1 Max Clad Oxidation, % *17 6.68 10.78 Max Core Wide, Oxidation %
  • 1 < 0.50 < 0.67 Coolable Geometry Yes Yes Yes (1) Same version of code was used in both cases.

Edn

"-1----Entergy 82

  • Methodology

- Cycle 16

"*New Approved Methodology Applied

"*CENPD-254-P-A, "Post -LOCA Long Term Cooling Evaluation Model", June 1980

- Cycle 1

  • Plant Specific Assessment 83-----Entergy
  • Analysis

- New methods more conservative than Cycle 1

- Power uprate

- Miscellaneous input update since Cycle 1 8t 84 'F-ý-En tergy

  • Results

- Hot leg injection initiated at 5 hours5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br /> results in maximum boric acid concentration of 23.3 wt%

- Less than acceptance limit of 27.6 wt%

- EOP guidance - 2 to 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> to initiate hot leg injection 85 ntergy

ECCSAnalsisI Conclusion ECCS Analysis Results Are Acceptable AEk 17ý7Entergy 86

Resolution of Open Issues IN I Bryan Daiber 87 z Entergy

  • No current open items
  • Draft Safety Evaluation notes some open items with respect to the radiological analyses

- Due to the timing and review process not resolved before issuance of SER

- These issues have now been resolved

""tk 88 ---- Entergy

- Issue

- Resolution 89 Entergy

  • Issue

-The operator response time was increased from 30 minutes in the License Application to 60 minutes in the Supplements

  • Resolution

-Acceptable results to the NRC staff have been presented in the supplemental information 90 ~Enterg)y

  • Issue The NRC Staff questioned the rate of exchange of air from the sprayed to unsprayed regions in containment due to forced flow.
  • Resolution

- Acceptable supplemental information describing the containment layout with respect to the containment fan intake and discharge has been provided to the Staff.

91Entergy

  • Issue

- November 2001 control room envelope integrated inleakage testing showed inleakage of approximately 134 scfm, which is greater than the analysis assumption of 10 scfm.

- Resolution

- Acceptable control room doses based on 61 scfm have been submitted to the Staff

- Commitment made to replace seal on VSF-9 (control room emergency ventilation fan and filter), reduces inleakage by 45 scfm

- Commitment to prevent pressurization of north wall due to 2VEF-56 fan discharge (switch gear room cooling fan), reduces inleakage by 49 scfm Am 92 E1trg

Resolution of Open Issues I

Conclusion No Open Issues AM 93 Entergy

ANO-2 Power Uprate, Risk Im p act Assessment I Bryan Daiber

-En

'----Entergy 94

"* Quantitative impact on at-power risk:

"* Impact on internal events core damage frequency (CDF)

"* Impact on internal events large early release fraction (LERF)

"* Impact on fire vulnerability

"* Qualitative impact on at-power risk:

"* Impact on seismic vulnerability

"* Impact on other external events (High winds and tornadoes, external flooding, transportation, and accidents at nearby facilities)

"* Qualitative impact on shutdown risk 95t=----En tergy

"* Started with latest Level-1 plant model

- 1997 plant model

"* Started with latest LERF model

"* Started with latest available fire assessment

- Updated initiating event frequencies

- Original P2 values

"* Started with latest IPEEE (seismic, external events) 6tk

-- E te g 96tE:

° Success criteria

  • Component failure rates
  • System fault tree analysis
  • Operator responses 9EEntergy

frequencies

- No new initiators identified

- No increase in initiator frequency

- No changes required; current model applicable to uprate 98 -ý-En tergy

  • Reviewed the Accident Sequence model and success criteria

- Only one change identified for LBLOCA

  • 2 of 4 HPSI valves to 3 of 4 for uprate
  • long term recirculation

- CENTS analyses were performed for selected accident scenarios

- Fault tree top logic updated for LBLOCA "E tergy effect 99  :'---Ent

Component Failure Rates I

  • Component failure rates were reviewed

- Equipment verified to operate within design limits

- Modifications were made to improve performance of certain equipment and systems

- Existing monitoring programs will account for additional wear AEL

- No adverse effects m:ý--En tergy 100

  • Plant modifications reviewed for impacts
  • System fault trees updated as necessary

- CSAS actuation logic to main feedwater and main steam isolation valves added to model 101 Entergy

  • Reviewed the operator actions
  • CENTS used to quantify the effect of uprate (available time for operator action)
  • Incorporated new times into the human reliability analysis (HRA) models 102

' Entergy

a DwoHa madelsdevelaped

- pre-uprate, 2A

- post-uprate, 2B

"* Quantified both cases

"* Reviewed and Compared results

"*Change in CDF (2.7 E-6, 16%)

- pre 1.70 E-5 /rx-yr

- post 1.97 E-5 /rx-yr

"* Within Region II(small changes)

Reg Guide 1.174 Ed t

  • En tergy 103

LERF

  • Started with Level 1 Results from 2A & 2B

- IPE level IIassessment is limited scope

- current level IIplant damage state binning factors applied

- minimal impact to plant damage state binning factors e Change in LERF (9.3 E-8, 24%)

- pre 3.87 E-7 /rx-yr

- post 4.80 E-7 /rx-yr o Within Region III (very small changes)

Reg Guide 1.174 __

104

-- Lntergy

- Initiating Event Frequencies

  • Current analysis for combustible loading not affected by uprate

- Component Failure Rates e No adverse effect

- Success Criteria e No change - minimal impact

- Operator Actions

  • CENTS analysis used to address available time for operator action 105---En tergy

"*Vulnerability analysis based on EPRI FIVE methodology - screening approach on each fire zone

"*Reviewed unscreened zones (CIDF > 1 E-6/rx-yr)

"*No new vulnerabilities or insights identified "106-'-En tergy

  • Seismic

- Seismic margin analysis

- Power level does not affect equipment survivability nor equipment response

- Power uprate does not modify safe shutdown pathway

- Seismic risk not impacted 107 *En tergy

"*High Winds / Tornadoes

- No impact due to power uprate

"*External Flooding

- No Impact due to power uprate

"*Transportation and Nearby Facility Accidents

- No impact due to power uprate 108

-En tergy

  • Qualitative Assessment Using Questions from Standard Review Plan (SRP)19

- Small decrease in available operator action time during shutdown

- Maintaining adequate defense-in-depth for shutdown safety functions via the Shutdown Operations Protection Plan (SOPP); minimizes impact of decreased available time

- No unique or significant impacts 109 ý_Entergy

No unique or significant impacts on:

- Level 1 Internal Events Frequencies

- Component Failure Rates

- IPEEE Internal Fire Analysis

- IPEEE Seismic Analysis

- IPEEE Other External Events Analysis

- Shutdown Risk

- Level-1 CDF

- LERF ,*

110 Entergy

Concluding Remarks Rick Lane 1--Entergy 111

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