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 B
i l ti i
1990 Began commercial operations in 1990
- Initial operating license until 2030 year license extension (2030-2050) in progress progress INPO Excellence Rating for eight-consecutive rating periods (16 years)
Record run leading into the latest eco d u ead g
to t e atest refueling (525 days)
Approximately 520 permanent employees 2
Seabrook Station provides approximately half of the electricity for New Hampshire, which is enough clean, 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 Brian Brown Seabrook Principal Engineer Larry Nicholson Fleet Licensing Director John Simons MPR General Mgr Power Projects Chris Bagley MPR Lead Engineer 3
Agenda U d t UT/FSEL t ti Update on UT/FSEL testing wrap-up Overview of Timeline
- Core testing
- Extensometers
- AMP refinement LAR development
- LAR development
- Walkdowns AMP Discussion Closing remarks 4
Update on MPR/UT Testing St t Status All test programs complete Owners Acceptance Review of test reports in progress Owner s Acceptance Review of test reports in progress Results Structural test programs showed no reduction in capacity for ASR expansion levels greater than plant for ASR expansion levels greater than plant
- Shear
- Reinforcement Anchorage and Flexure
- Anchor Bolts Instrument program demonstrated accuracy and reliability of extensometers 5
UT T ti Seabrook Alkali Silica Reaction Issue Timeline 2016 Refined CEB LARInternal Review with all LAR Document April May June July ScheduleNRCStaff LARPreSubmittal Meetings (NEE/SGH/MPR)
UTTesting DraftRollup ReporttoNEE (MPR)
RefinedCEB Analysis&
SubmittoNEE (SGH)
LARDraftedto NEESeabrookfor Review(MPR)
Reviewwithall Comments Incorporated atNEE LARDocument SubmittaltoNRC (NEE)
LAR LAR NRC Pre-submittal Meeting Window (April -May )
MPR4153Correlation ReportRevision CorrelationCore BoresExtracted
&Tested&
Extensometers Installed Commence Regulatory Review of LAR RemainderofTier3Core Bores/Extensometers Installation AllTier3ASR AreasMonitoring Extensometers Installed C
W k
January May CoreBores&
Sampling/
Extensometer Susceptibility Evaluationon14 RemainingStructures Susceptibility Evaluationon1st Groupof12Most Vulnerable Structures June December Commence Work September December FEA Analysis Structures RHRVault Core Bores January March April Crack Gauges Installed/Core Bores Taken Petrography/Inspection Periodic Monitoring AnalyticalFEA Analysison6most VulnerableStructures Commence Work SMP/AMP P CoreBores CEB Walkdown January March Periodic Structures Monitoring for Equipment Effects Monitoring Plan Review (RAI)
LAR Submitted Inspections/ Walk downs Completed Commence Work SMP/AMP Process SMP/AMP Process 6
July Fall 2016 License Renewal
NRC Questions Topic:
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 to Behavior of Seabrook Structures Expansion behavior Applicability of modulus/expansion correlation from MPR 4153 for determining expansion to date at plant MPR-4153 for determining expansion to date at plant
Response
AMP will include evaluation of plant data for consistency i h i
b h i
b d i with expansion behavior observed in 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 favorably to 8
p y
published data for expansion
NRC Q estions NRC Questions Topic:
ASR effect on rebar ASR effect on rebar
Response
AMP to be revised as a result of ASR effects with respect to current licensing basis Structural analysis to confirm rebar stresses will be y
within Code provisions Expansion limits will be set from building structural analyses 9
NRC Questions T
i Topic:
Effect of Concrete Backfill on Below Grade Structures Reconciliation of 12/2015 RAI response against plant 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 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 Structural analysis will account for the external load
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
Scope of Program p
g Topic:
Define structures in scope of AMP for deformation and 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 t
M it d
I t d Parameters Monitored or Inspected Topic:
Provide the link between the parameters monitored and the p
structural functionality and building deformation
Response
AMP monitoring will include localized ASR-induced AMP monitoring will include localized ASR-induced expansion strain as well as deformation of the concrete structures
- Data - CCI, through-thickness expansion, deformation Data CCI, 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 f ti intended function Link to structural functionality is established via analysis of the structure to assess rebar yielding 13 Analysis will establish parameters monitored
Parameters Monitored or Inspected Topic:
Monitoring for discrete macro cracking and deformation
Response
Parameters to be monitored will include localized ASR i d d
i i
ll d f i
f h induced expansion strain as well as deformation of the concrete structures.
- Examples include Seismic gap measurements, building measurements building specific monitoring methods (Invar wire measurements, building specific monitoring methods (Invar wire, Laser targets), SMP walkdowns 14
Parameters Monitored or Inspected Topic:
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 impacted by deformation will be age managed by a new plant specific AMP 15
Detection of Aging Effects Topic:
Topic:
Early detection of degradation before loss of intended function.
Response
A new plant specific AMP will be developed using a tiered p
p p
g approach based on available margin.
- Monitoring and detection prior to significant margin reduction
- Enter into corrective action program Enter into corrective action program
- Input into SMP
- Restore equipment to original condition 16
Detection of Aging Effects Continued Detection of Aging Effects Continued Topic:
Monitoring of structures not adjacent to misaligned Monitoring of structures not adjacent to misaligned components
Response
Response:
Misaligned components are not the only parameters monitored for building deformation M
it i
ill tili bi ti f i t
i l di Monitoring will utilize a combination of inputs including ASR monitoring techniques, (CCI, extensometers, deformation) and monitoring of key assumptions in structures analysis along with equipment impacted by structures analysis along with equipment impacted by deformation 17
M it i
d T di Monitoring and Trending 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 utilizing a tiered approach and frequencies eque c es ut g a t e ed app oac a d eque c es established to ensure that timely corrective actions 18
Monitoring and Trending Topic:
Topic:
Data collection and evaluation
Response
Analysis of the structure includes additional margin on structural design to ensure that timely corrective actions 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 loads to some fraction of the maximum allowable self-straining load.
19
Monitoring and Trending T
i Topic:
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 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 Parameters monitored will be established and trended based on bounding limits in the structural analysis.
20
Acceptance Criteria T
i Topic:
Process for calculating conditional acceptance criteria to ensure structure and component intended functions will be maintained under all CLB design conditions maintained under all CLB design conditions
Response
p A structural model is developed where ASR induced expansion is applied to the structure.
Added load due to ASR is combined with other CLB loads Added load due to ASR is combined with other CLB 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 ill consider operating e perience c rrent & f t re AMP will consider operating experiencecurrent & future Assigned Project Manager Engaged structural engineering firms g g g
g
- Inspection of concrete structures
- Analysis of concrete structures Leveraging CEB experience to other ASR affected Leveraging CEB experience to other ASR-affected structures
- Walkdown process E
l ti 22
- Evaluation process
Closing Remarks MPR/UT t ti d
t t d d
ti i
t t
l MPR/UT testing demonstrated no reduction in structural 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 19 crack gauges sta g
9 c 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 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 B
i l ti i
1990 Began commercial operations in 1990
- Initial operating license until 2030 year license extension (2030-2050) in progress progress INPO Excellence Rating for eight-consecutive rating periods (16 years)
Record run leading into the latest eco d u ead g
to t e atest refueling (525 days)
Approximately 520 permanent employees 2
Seabrook Station provides approximately half of the electricity for New Hampshire, which is enough clean, 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 Brian Brown Seabrook Principal Engineer Larry Nicholson Fleet Licensing Director John Simons MPR General Mgr Power Projects Chris Bagley MPR Lead Engineer 3
Agenda U d t UT/FSEL t ti Update on UT/FSEL testing wrap-up Overview of Timeline
- Core testing
- Extensometers
- AMP refinement LAR development
- LAR development
- Walkdowns AMP Discussion Closing remarks 4
Update on MPR/UT Testing St t Status All test programs complete Owners Acceptance Review of test reports in progress Owner s Acceptance Review of test reports in progress Results Structural test programs showed no reduction in capacity for ASR expansion levels greater than plant for ASR expansion levels greater than plant
- Shear
- Reinforcement Anchorage and Flexure
- Anchor Bolts Instrument program demonstrated accuracy and reliability of extensometers 5
UT T ti Seabrook Alkali Silica Reaction Issue Timeline 2016 Refined CEB LARInternal Review with all LAR Document April May June July ScheduleNRCStaff LARPreSubmittal Meetings (NEE/SGH/MPR)
UTTesting DraftRollup ReporttoNEE (MPR)
RefinedCEB Analysis&
SubmittoNEE (SGH)
LARDraftedto NEESeabrookfor Review(MPR)
Reviewwithall Comments Incorporated atNEE LARDocument SubmittaltoNRC (NEE)
LAR LAR NRC Pre-submittal Meeting Window (April -May )
MPR4153Correlation ReportRevision CorrelationCore BoresExtracted
&Tested&
Extensometers Installed Commence Regulatory Review of LAR RemainderofTier3Core Bores/Extensometers Installation AllTier3ASR AreasMonitoring Extensometers Installed C
W k
January May CoreBores&
Sampling/
Extensometer Susceptibility Evaluationon14 RemainingStructures Susceptibility Evaluationon1st Groupof12Most Vulnerable Structures June December Commence Work September December FEA Analysis Structures RHRVault Core Bores January March April Crack Gauges Installed/Core Bores Taken Petrography/Inspection Periodic Monitoring AnalyticalFEA Analysison6most VulnerableStructures Commence Work SMP/AMP P CoreBores CEB Walkdown January March Periodic Structures Monitoring for Equipment Effects Monitoring Plan Review (RAI)
LAR Submitted Inspections/ Walk downs Completed Commence Work SMP/AMP Process SMP/AMP Process 6
July Fall 2016 License Renewal
NRC Questions Topic:
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 to Behavior of Seabrook Structures Expansion behavior Applicability of modulus/expansion correlation from MPR 4153 for determining expansion to date at plant MPR-4153 for determining expansion to date at plant
Response
AMP will include evaluation of plant data for consistency i h i
b h i
b d i with expansion behavior observed in 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 favorably to 8
p y
published data for expansion
NRC Q estions NRC Questions Topic:
ASR effect on rebar ASR effect on rebar
Response
AMP to be revised as a result of ASR effects with respect to current licensing basis Structural analysis to confirm rebar stresses will be y
within Code provisions Expansion limits will be set from building structural analyses 9
NRC Questions T
i Topic:
Effect of Concrete Backfill on Below Grade Structures Reconciliation of 12/2015 RAI response against plant 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 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 Structural analysis will account for the external load
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
Scope of Program p
g Topic:
Define structures in scope of AMP for deformation and 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 t
M it d
I t d Parameters Monitored or Inspected Topic:
Provide the link between the parameters monitored and the p
structural functionality and building deformation
Response
AMP monitoring will include localized ASR-induced AMP monitoring will include localized ASR-induced expansion strain as well as deformation of the concrete structures
- Data - CCI, through-thickness expansion, deformation Data CCI, 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 f ti intended function Link to structural functionality is established via analysis of the structure to assess rebar yielding 13 Analysis will establish parameters monitored
Parameters Monitored or Inspected Topic:
Monitoring for discrete macro cracking and deformation
Response
Parameters to be monitored will include localized ASR i d d
i i
ll d f i
f h induced expansion strain as well as deformation of the concrete structures.
- Examples include Seismic gap measurements, building measurements building specific monitoring methods (Invar wire measurements, building specific monitoring methods (Invar wire, Laser targets), SMP walkdowns 14
Parameters Monitored or Inspected Topic:
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 impacted by deformation will be age managed by a new plant specific AMP 15
Detection of Aging Effects Topic:
Topic:
Early detection of degradation before loss of intended function.
Response
A new plant specific AMP will be developed using a tiered p
p p
g approach based on available margin.
- Monitoring and detection prior to significant margin reduction
- Enter into corrective action program Enter into corrective action program
- Input into SMP
- Restore equipment to original condition 16
Detection of Aging Effects Continued Detection of Aging Effects Continued Topic:
Monitoring of structures not adjacent to misaligned Monitoring of structures not adjacent to misaligned components
Response
Response:
Misaligned components are not the only parameters monitored for building deformation M
it i
ill tili bi ti f i t
i l di Monitoring will utilize a combination of inputs including ASR monitoring techniques, (CCI, extensometers, deformation) and monitoring of key assumptions in structures analysis along with equipment impacted by structures analysis along with equipment impacted by deformation 17
M it i
d T di Monitoring and Trending 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 utilizing a tiered approach and frequencies eque c es ut g a t e ed app oac a d eque c es established to ensure that timely corrective actions 18
Monitoring and Trending Topic:
Topic:
Data collection and evaluation
Response
Analysis of the structure includes additional margin on structural design to ensure that timely corrective actions 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 loads to some fraction of the maximum allowable self-straining load.
19
Monitoring and Trending T
i Topic:
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 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 Parameters monitored will be established and trended based on bounding limits in the structural analysis.
20
Acceptance Criteria T
i Topic:
Process for calculating conditional acceptance criteria to ensure structure and component intended functions will be maintained under all CLB design conditions maintained under all CLB design conditions
Response
p A structural model is developed where ASR induced expansion is applied to the structure.
Added load due to ASR is combined with other CLB loads Added load due to ASR is combined with other CLB 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 ill consider operating e perience c rrent & f t re AMP will consider operating experiencecurrent & future Assigned Project Manager Engaged structural engineering firms g g g
g
- Inspection of concrete structures
- Analysis of concrete structures Leveraging CEB experience to other ASR affected Leveraging CEB experience to other ASR-affected structures
- Walkdown process E
l ti 22
- Evaluation process
Closing Remarks MPR/UT t ti d
t t d d
ti i
t t
l MPR/UT testing demonstrated no reduction in structural 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 19 crack gauges sta g
9 c 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 licensing basis to address ASR and deformation
- Revised Part 54 Aging Management Program to address ASR and deformation 23