ML16146A200
| ML16146A200 | |
| Person / Time | |
|---|---|
| Site: | Seabrook  |
| Issue date: | 04/28/2016 |
| From: | NextEra Energy Seabrook |
| To: | Tam Tran Office of Nuclear Reactor Regulation |
| Tran T, NRR/DLR, 415-8517 | |
| Shared Package | |
| ML16146A172 | List: |
| References | |
| DLR-16-0133 | |
| Download: ML16146A200 (23) | |
Text
Seabrook Station License Renewal Application Consideration of ASR April 28, 2016
Seabrook is one of the newest plants in the United States and was acquired by NextEra Energy in 2002 Seabrook at a Glance
- Began B commercial i l operations ti in i 1990
- Initial operating license until 2030 year license extension (2030-2050) in progress
- INPO Excellence Rating for eight-consecutive rating periods (16 years)
- Record eco d runu leading ead g into to the t e latest atest refueling (525 days)
- Approximately 520 permanent employees Seabrook Station provides approximately half of the electricity for New Hampshire, which is enough clean, 2 reliable power for 1.2 million homes
NextEra Seabrook & MPR Attendees
- Ken Browne Seabrook ASR Project Manager
- Mike Ossing Seabrook Licensing Manager
- Ed Carley Seabrook License Renewal Supv.
- Brian Brown Seabrook Principal Engineer
- Larry Nicholson Fleet Licensing Director
- John Simons MPR General Mgr Power Projects
- Chris Bagley MPR Lead Engineer 3
Agenda
- Update U d t on UT/FSEL testing t ti wrap-up
- Overview of Timeline
- Core testing g
- Extensometers
- AMP refinement
- LAR development
- Walkdowns
- AMP Discussion
- Closing remarks 4
Update on MPR/UT Testing Status St t
- All test programs complete
- Owner Owners s Acceptance Review of test reports in progress Results
- Structural test programs showed no reduction in capacity for ASR expansion levels greater than plant
- Shear
- Reinforcement Anchorage and Flexure
- Anchor Bolts
- Instrument program demonstrated accuracy and reliability of extensometers 5
Seabrook Alkali Silica Reaction Issue Timeline 2016 LAR Internal Refined CEB Review with all LAR Document Schedule NRC Staff UT TTesting ti LAR Drafted to Analysis & Comments Submittal to NRC LAR PreSubmittal Draft Rollup NEE Seabrook for Submit to NEE Incorporated (NEE)
Meetings Report to NEE Review (MPR) (SGH) at NEE (NEE/SGH/MPR) (MPR)
LAR April May June July LAR NRC Pre-submittal Meeting Window (April -May ) Commence Regulatory Review of LAR Correlation Core Bores Extracted MPR4153 Correlation
& Tested & Report Revision All Tier 3 ASR Extensometers Remainder of Tier 3 Core Areas Monitoring Installed Bores/Extensometers Extensometers Installed Installation C
Commence W Work k Core Bores &
Sampling/ January May June December Extensometer Susceptibility Evaluation on 1st Susceptibility Group of 12 Most Evaluation on 14 Vulnerable Remaining Structures Structures FEA Analysis September December Crack Gauges Commence Work Installed/Core Petrography/Inspection Analytical FEA Bores Taken Analysis on 6 most RHR Vault January March April Periodic Monitoring Vulnerable Structures Core Bores SMP/AMP Process P
Commence Work Inspections/ Walk downs Completed CEB Periodic Structures Monitoring for Walkdown January March Equipment Effects SMP/AMP Process Monitoring Plan Review (RAI) LAR Submitted License July Fall 2016 Renewal 6
NRC Questions Topic:
Incorporation of future research into ASR AMP
Response
- Seabrook will remain fully engaged in ongoing research and industry experience
- Seabrook plant specific OE will be documented for analysis
- Industry leadership role with EPRI and NEI
- Monitoring of various government sponsored and international research
- Insights will be evaluated against adequacy of AMP
- AMP will be revised to ensure effectiveness 7
NRC Questions Q
Topic:
Validation that Large-Scale Testing Results are Comparable to Behavior of Seabrook Structures
- Expansion behavior
- Applicability of modulus/expansion correlation from MPR 4153 for determining expansion to date at plant MPR-4153
Response
- AMP will include evaluation of plant data for consistency with i h expansioni behavior b h i observedb d in i test programs
- Qualitative comparison of trends for in-plane versus through-thickness expansion
- Expansion within limits set based on test programs
- Cores inspected to confirm lack of edge-effect cracking
- Modulus correlation in MPR-4153 compares p favorablyy to published data for expansion 8
NRC Q Questions estions Topic:
ASR effect on rebar
Response
- Structural analysis y to confirm rebar stresses will be within Code provisions
- Expansion limits will be set from building structural analyses 9
NRC Questions Topic:
T i Effect of Concrete Backfill on Below Grade Structures
- Reconciliation of 12/2015 RAI response against plant experience with building deformation
- Representativeness of testing
Response
- Clarification: expansion of structures monitored in all directions
- Effect of concrete backfill on structure
- Applies an external load to the adjacent structure
- Does not prevent expansion in through-thickness direction (can move inward)
- Structural analysis will account for the external load 10
NRC Questions Topic:
Uniform ASR versus Localized ASR
Response
- Structural Capacity p y
- Uniform ASR expansion has a higher impact on structural performance.
- Building Deformation
- Impact of localized expansion addressed in analyses 11
Scopep of Program g
Topic:
Define structures in scope of AMP for deformation and discrete macro cracking due to ASR
Response
- All buildings within the scope of License Renewal are currently included in the revised AMP program
- Deformation and discrete macro cracking will be included as a program element for all buildings in scope of License Renewal 12
P Parameterst M Monitored it d or Inspected I t d Topic:
Provide the link between the p parameters monitored and the structural functionality and building deformation
Response
- AMP monitoring will include localized ASR-induced expansion strain as well as deformation of the concrete structures
- Data - CCI, through-thickness through thickness expansion, deformation inspections, crack gauges, invar wire
- Limits defined in the structural analysis will corroborate the extent of degradation including determination of limits prior to loss of i t d d ffunction intended ti
- Link to structural functionality is established via analysis of the structure to assess rebar yielding
- Analysis will establish parameters monitored 13
Parameters Monitored or Inspected Topic:
Monitoring for discrete macro cracking and deformation
Response
- Parameters to be monitored will include localized ASR i d inducedd expansion i strain i as wellll as deformation d f i off the h
concrete structures.
- Examples include Seismic gap measurements, building measurements building specific monitoring methods (Invar wire measurements, wire, Laser targets), SMP walkdowns 14
Parameters Monitored or Inspected Topic:
Aging management of non-structural components for ASR
Response
- In-scope Non-Structural Equipment and Components impacted by deformation will be age managed by a new plant specific AMP 15
Detection of Aging Effects Topic:
Early detection of degradation before loss of intended function.
Response
- A new p plant specific p AMP will be developed p using g a tiered approach based on available margin.
- Monitoring and detection prior to significant margin reduction
- Enter into corrective action program
- Input into SMP
- Restore equipment to original condition 16
Detection of Aging Effects Continued Topic:
Monitoring of structures not adjacent to misaligned components
Response
- Misaligned components are not the only parameters monitored for building deformation
- Monitoring M it i will ill utilize tili a combination bi ti off inputs i t including i l di ASR monitoring techniques, (CCI, extensometers, deformation) and monitoring of key assumptions in structures analysis along with equipment impacted by deformation 17
M it i and Monitoring d Trending T di Topic:
Monitoring and trending activities will provide a prediction of the extent and rate of degradation
Response
- Data will be trended based on design limits and frequencies eque c es ut utilizing g a tiered t e ed approach app oac and a d frequencies eque c es established to ensure that timely corrective actions 18
Monitoring and Trending Topic:
Data collection and evaluation
Response
- Analysis of the structure includes additional margin on structural design to ensure that timely corrective actions are taken prior to exceeding design code limits. Data will be trended based on limits and frequencies established in the structural analysis.
- Margin is defined through a tiered approach where threshold limits are defined as the maximum allowable measurement for each monitoring element that limits the self straining loads to some fraction of the maximum self-straining allowable self-straining load.
19
Monitoring and Trending Topic:
T i Describe how the data will be trended over time
Response
- Data will be trended based on limits and frequencies established in the structural analysis to ensure that timely corrective actions are implemented prior to exceeding design code limits.
- Parameters monitored will be established and trended based on bounding limits in the structural analysis.
20
Acceptance Criteria Topic:
T i Process for calculating conditional acceptance criteria to ensure structure and component intended functions will be maintained under all CLB design conditions
Response
p
- A structural model is developed where ASR induced expansion is applied to the structure.
loads
- Resultant load combinations are evaluated to validate compliance with CLB structural design code requirements 21
Operating Experience Topic:
Impacts of internal Operating Experience will be adequately considered in AMP.
Response
- AMP willill consider operating experiencecurrent e perience c rrent & ffuture t re
- Assigned Project Manager g g structural engineering
- Engaged g g firms
- Inspection of concrete structures
- Analysis of concrete structures
- Leveraging CEB experience to other ASR ASR-affected affected structures
- Walkdown process
- Evaluation E l ti process 22
Closing Remarks
- MPR/UT ttesting ti d demonstrated t t d no reduction d ti iin structural t t l capacity and the effects can be monitored
- Extensive onsite work in 2016
- Withdrawing 115 core bores samples in areas throughout plant
- Installing 52 extensometers to provide monitoring capability
- Installing sta g 19 9 ccrack ac gauges
- Seabrook plans to submit in July 2016
- Part 50 License Amendment Request to reconcile the current licensing basis to address ASR and deformation
- Revised Part 54 Aging Management Program to address ASR and deformation 23
Seabrook Station License Renewal Application Consideration of ASR April 28, 2016
Seabrook is one of the newest plants in the United States and was acquired by NextEra Energy in 2002 Seabrook at a Glance
- Began B commercial i l operations ti in i 1990
- Initial operating license until 2030 year license extension (2030-2050) in progress
- INPO Excellence Rating for eight-consecutive rating periods (16 years)
- Record eco d runu leading ead g into to the t e latest atest refueling (525 days)
- Approximately 520 permanent employees Seabrook Station provides approximately half of the electricity for New Hampshire, which is enough clean, 2 reliable power for 1.2 million homes
NextEra Seabrook & MPR Attendees
- Ken Browne Seabrook ASR Project Manager
- Mike Ossing Seabrook Licensing Manager
- Ed Carley Seabrook License Renewal Supv.
- Brian Brown Seabrook Principal Engineer
- Larry Nicholson Fleet Licensing Director
- John Simons MPR General Mgr Power Projects
- Chris Bagley MPR Lead Engineer 3
Agenda
- Update U d t on UT/FSEL testing t ti wrap-up
- Overview of Timeline
- Core testing g
- Extensometers
- AMP refinement
- LAR development
- Walkdowns
- AMP Discussion
- Closing remarks 4
Update on MPR/UT Testing Status St t
- All test programs complete
- Owner Owners s Acceptance Review of test reports in progress Results
- Structural test programs showed no reduction in capacity for ASR expansion levels greater than plant
- Shear
- Reinforcement Anchorage and Flexure
- Anchor Bolts
- Instrument program demonstrated accuracy and reliability of extensometers 5
Seabrook Alkali Silica Reaction Issue Timeline 2016 LAR Internal Refined CEB Review with all LAR Document Schedule NRC Staff UT TTesting ti LAR Drafted to Analysis & Comments Submittal to NRC LAR PreSubmittal Draft Rollup NEE Seabrook for Submit to NEE Incorporated (NEE)
Meetings Report to NEE Review (MPR) (SGH) at NEE (NEE/SGH/MPR) (MPR)
LAR April May June July LAR NRC Pre-submittal Meeting Window (April -May ) Commence Regulatory Review of LAR Correlation Core Bores Extracted MPR4153 Correlation
& Tested & Report Revision All Tier 3 ASR Extensometers Remainder of Tier 3 Core Areas Monitoring Installed Bores/Extensometers Extensometers Installed Installation C
Commence W Work k Core Bores &
Sampling/ January May June December Extensometer Susceptibility Evaluation on 1st Susceptibility Group of 12 Most Evaluation on 14 Vulnerable Remaining Structures Structures FEA Analysis September December Crack Gauges Commence Work Installed/Core Petrography/Inspection Analytical FEA Bores Taken Analysis on 6 most RHR Vault January March April Periodic Monitoring Vulnerable Structures Core Bores SMP/AMP Process P
Commence Work Inspections/ Walk downs Completed CEB Periodic Structures Monitoring for Walkdown January March Equipment Effects SMP/AMP Process Monitoring Plan Review (RAI) LAR Submitted License July Fall 2016 Renewal 6
NRC Questions Topic:
Incorporation of future research into ASR AMP
Response
- Seabrook will remain fully engaged in ongoing research and industry experience
- Seabrook plant specific OE will be documented for analysis
- Industry leadership role with EPRI and NEI
- Monitoring of various government sponsored and international research
- Insights will be evaluated against adequacy of AMP
- AMP will be revised to ensure effectiveness 7
NRC Questions Q
Topic:
Validation that Large-Scale Testing Results are Comparable to Behavior of Seabrook Structures
- Expansion behavior
- Applicability of modulus/expansion correlation from MPR 4153 for determining expansion to date at plant MPR-4153
Response
- AMP will include evaluation of plant data for consistency with i h expansioni behavior b h i observedb d in i test programs
- Qualitative comparison of trends for in-plane versus through-thickness expansion
- Expansion within limits set based on test programs
- Cores inspected to confirm lack of edge-effect cracking
- Modulus correlation in MPR-4153 compares p favorablyy to published data for expansion 8
NRC Q Questions estions Topic:
ASR effect on rebar
Response
- Structural analysis y to confirm rebar stresses will be within Code provisions
- Expansion limits will be set from building structural analyses 9
NRC Questions Topic:
T i Effect of Concrete Backfill on Below Grade Structures
- Reconciliation of 12/2015 RAI response against plant experience with building deformation
- Representativeness of testing
Response
- Clarification: expansion of structures monitored in all directions
- Effect of concrete backfill on structure
- Applies an external load to the adjacent structure
- Does not prevent expansion in through-thickness direction (can move inward)
- Structural analysis will account for the external load 10
NRC Questions Topic:
Uniform ASR versus Localized ASR
Response
- Structural Capacity p y
- Uniform ASR expansion has a higher impact on structural performance.
- Building Deformation
- Impact of localized expansion addressed in analyses 11
Scopep of Program g
Topic:
Define structures in scope of AMP for deformation and discrete macro cracking due to ASR
Response
- All buildings within the scope of License Renewal are currently included in the revised AMP program
- Deformation and discrete macro cracking will be included as a program element for all buildings in scope of License Renewal 12
P Parameterst M Monitored it d or Inspected I t d Topic:
Provide the link between the p parameters monitored and the structural functionality and building deformation
Response
- AMP monitoring will include localized ASR-induced expansion strain as well as deformation of the concrete structures
- Data - CCI, through-thickness through thickness expansion, deformation inspections, crack gauges, invar wire
- Limits defined in the structural analysis will corroborate the extent of degradation including determination of limits prior to loss of i t d d ffunction intended ti
- Link to structural functionality is established via analysis of the structure to assess rebar yielding
- Analysis will establish parameters monitored 13
Parameters Monitored or Inspected Topic:
Monitoring for discrete macro cracking and deformation
Response
- Parameters to be monitored will include localized ASR i d inducedd expansion i strain i as wellll as deformation d f i off the h
concrete structures.
- Examples include Seismic gap measurements, building measurements building specific monitoring methods (Invar wire measurements, wire, Laser targets), SMP walkdowns 14
Parameters Monitored or Inspected Topic:
Aging management of non-structural components for ASR
Response
- In-scope Non-Structural Equipment and Components impacted by deformation will be age managed by a new plant specific AMP 15
Detection of Aging Effects Topic:
Early detection of degradation before loss of intended function.
Response
- A new p plant specific p AMP will be developed p using g a tiered approach based on available margin.
- Monitoring and detection prior to significant margin reduction
- Enter into corrective action program
- Input into SMP
- Restore equipment to original condition 16
Detection of Aging Effects Continued Topic:
Monitoring of structures not adjacent to misaligned components
Response
- Misaligned components are not the only parameters monitored for building deformation
- Monitoring M it i will ill utilize tili a combination bi ti off inputs i t including i l di ASR monitoring techniques, (CCI, extensometers, deformation) and monitoring of key assumptions in structures analysis along with equipment impacted by deformation 17
M it i and Monitoring d Trending T di Topic:
Monitoring and trending activities will provide a prediction of the extent and rate of degradation
Response
- Data will be trended based on design limits and frequencies eque c es ut utilizing g a tiered t e ed approach app oac and a d frequencies eque c es established to ensure that timely corrective actions 18
Monitoring and Trending Topic:
Data collection and evaluation
Response
- Analysis of the structure includes additional margin on structural design to ensure that timely corrective actions are taken prior to exceeding design code limits. Data will be trended based on limits and frequencies established in the structural analysis.
- Margin is defined through a tiered approach where threshold limits are defined as the maximum allowable measurement for each monitoring element that limits the self straining loads to some fraction of the maximum self-straining allowable self-straining load.
19
Monitoring and Trending Topic:
T i Describe how the data will be trended over time
Response
- Data will be trended based on limits and frequencies established in the structural analysis to ensure that timely corrective actions are implemented prior to exceeding design code limits.
- Parameters monitored will be established and trended based on bounding limits in the structural analysis.
20
Acceptance Criteria Topic:
T i Process for calculating conditional acceptance criteria to ensure structure and component intended functions will be maintained under all CLB design conditions
Response
p
- A structural model is developed where ASR induced expansion is applied to the structure.
loads
- Resultant load combinations are evaluated to validate compliance with CLB structural design code requirements 21
Operating Experience Topic:
Impacts of internal Operating Experience will be adequately considered in AMP.
Response
- AMP willill consider operating experiencecurrent e perience c rrent & ffuture t re
- Assigned Project Manager g g structural engineering
- Engaged g g firms
- Inspection of concrete structures
- Analysis of concrete structures
- Leveraging CEB experience to other ASR ASR-affected affected structures
- Walkdown process
- Evaluation E l ti process 22
Closing Remarks
- MPR/UT ttesting ti d demonstrated t t d no reduction d ti iin structural t t l capacity and the effects can be monitored
- Extensive onsite work in 2016
- Withdrawing 115 core bores samples in areas throughout plant
- Installing 52 extensometers to provide monitoring capability
- Installing sta g 19 9 ccrack ac gauges
- Seabrook plans to submit in July 2016
- Part 50 License Amendment Request to reconcile the current licensing basis to address ASR and deformation
- Revised Part 54 Aging Management Program to address ASR and deformation 23