ML18222A292
| ML18222A292 | |
| Person / Time | |
|---|---|
| Site: | Seabrook  |
| Issue date: | 08/10/2018 |
| From: | Mel Gray Division of Reactor Safety I |
| To: | Nazar M NextEra Energy Seabrook |
| References | |
| IR 2018011 | |
| Download: ML18222A292 (14) | |
See also: IR 05000443/2018011
Text
UNITED STATES
NUCLEAR REGULATORY COMMISSION
REGION I
2100 RENAISSANCE BOULEVARD, SUITE 100
KING OF PRUSSIA, PA 19406-2713
August 10, 2018
Mr. Mano Nazar
President and Chief Nuclear Officer
Nuclear Division
NextEra Energy Seabrook, LLC
Mail Stop: EX/JB
700 Universe Blvd.
Juno Beach, FL 33408
SUBJECT: SEABROOK STATION, UNIT NO. 1 - FOLLOW-UP OF ALKALI SILICA
REACTION OPEN ITEM LICENSE RENEWAL INSPECTION REPORT
Dear Mr. Nazar:
On May 3, 2018, the U.S. Nuclear Regulatory Commission (NRC) completed an on-site team
inspection at Seabrook Station, Unit No. 1 as part of the license renewal review process. The
scope of this inspection was to examine plant activities and documents that support the
application for a renewed license at Seabrook Station as they relate to managing the effects of
aging due to alkali silica reaction (ASR) in concrete structures. The NRC inspectors discussed
the results of this inspection with Mr. Christopher Domingos, Site Director, and other members
of your staff via a teleconference exit on June 27, 2018. The results of this inspection are
documented in the enclosed report.
The presence of ASR in Seabrook Station concrete structures was identified in 2010. The NRC
completed a license renewal team inspection in 2011, which determined that except for the ASR
issue, the inspection results supported a conclusion of reasonable assurance with respect to
managing the effects of aging in systems, structures and components identified in NextEras
license renewal application for the Seabrook Station. The team noted, at that time, NextEra
was developing programs to manage the effects of ASR on Seabrook Station concrete
structures and that additional NRC inspection was warranted once these programs were
finalized. The NRC subsequently completed two team inspections on this technical issue, and
since 2013, conducted inspections approximately every six months to evaluate NextEras
activities to develop and implement your structural aging management programs. This
inspection follows-up on the 2011 license renewal inspection.
The inspectors reviewed procedures and records related to your monitoring of the effects of
ASR in Seabrook concrete structures, observed activities, interviewed personnel, and
conducted plant walk downs of several areas to independently assess structural condition. No
findings or violations of NRC requirements were identified during this inspection.
The inspection team concluded that for the ASR issue, your staff adequately performed scoping
and screening of structures, systems, and components as required in 10 CFR 54.4(a) and
54.21, respectively, and established aging management programs as described in the license
renewal application. The inspection further concluded the documentation supporting the
application was in an auditable and retrievable form. The inspection results support the
conclusion that there is reasonable assurance that the effects of aging due to ASR in the
Seabrook systems, structures, and components will be managed through implementation of
M. Nazar 2
these programs as described in the application for a renewed license currently under review by
the NRC Office of Nuclear Reactor Regulation.
This letter, its enclosure, and your response (if any) will be made available for public inspection
and copying at http://www.nrc.gov/reading-rm/adams.html and at the NRC Public Document
Room in accordance with 10 CFR 2.390, Public Inspections, Exemptions, Requests for
Withholding.
Sincerely,
/RA/
Mel Gray, Chief
Engineering Branch 1
Division of Reactor Safety
Docket No. 50-443
License No. NPF-86
Enclosure:
Inspection Report 05000443/2018011
cc w/encl: Distribution via ListServ
Non-Sensitive Publicly Available
SUNSI Review
Sensitive Non-Publicly Available
OFFICE RI/DRS RI/DRP RI/DRS
NAME NFloyd via email FBower via email MGray
DATE 8/7/18 8/7/18 8/10/18
1
U.S. NUCLEAR REGULATORY COMMISSION
Inspection Report
Docket Number: 50-443
License Number: NPF-86
Report Number: 05000443/2018011
Enterprise Identifier: I-2018-011-0039
Licensee: NextEra Energy Seabrook, LLC (NextEra)
Facility: Seabrook Station, Unit No. 1 (Seabrook)
Location: Seabrook, NH
Inspection Dates: 04/30/2018 - 05/03/2018 (on-site)
05/23/2018 - 06/27/2018 (in-office)
Team Lead: Niklas Floyd, Senior Reactor Inspector, Region I, DRS
Inspector: Angela Buford, Structural Engineer, NRR, DE
Approved By: Mel Gray, Chief
Engineering Branch 1
Division of Reactor Safety
Enclosure
2
SUMMARY
The U.S. Nuclear Regulatory Commission (NRC) conducted a license renewal follow-up
inspection at the Seabrook Station in accordance with the Reactor Oversight Process. The
Reactor Oversight Process is the NRCs program for overseeing the safe operation of
commercial nuclear power reactors. Refer to
https://www.nrc.gov/reactors/operating/oversight.html for more information.
NRC inspectors from Region I and the Office of Nuclear Reactor Regulation performed on-site
inspections of the applicants license renewal activities, specifically those related to alkali-silica
reaction (ASR). The team performed the evaluations in accordance with Manual Chapter 2516,
Policy and Guidance for the License Renewal Inspection Programs, and Inspection Procedure 71002, License Renewal Inspection. With regards to ASR, the team concluded the applicant
adequately performed scoping and screening of structures, systems, and components as
required in 10 CFR 54.4(a) and 54.21, respectively, and established aging management
programs as described in the license renewal application. The team concluded that the
applicant provided documentation that supported the application and inspection process in an
auditable and retrievable form. The inspection results support the conclusion that there is
reasonable assurance that the effects of aging due to ASR in the Seabrook systems, structures,
and components will be managed through implementation of these programs as described in
the application for a renewed license currently under review by the NRC Office of Nuclear
Reactor Regulation.
No findings or more-than-minor violations were identified.
3
INSPECTION SCOPE
This inspection was conducted using the appropriate portions of the applicable inspection
procedures (IPs) in effect at the beginning of the inspection unless otherwise noted. Currently
approved IPs with their attached revision histories are located on the public website at
http://www.nrc.gov/reading-rm/doc-collections/insp-manual/inspection-procedure/index.html.
The inspectors reviewed selected procedures and records, observed activities, and interviewed
personnel to assess NextEras performance and compliance with Commission rules and
regulations, license conditions, site procedures, and standards.
OTHER ACTIVITIES - TEMPORARY INSTRUCTIONS, INFREQUENT, AND ABNORMAL
71002 - License Renewal
Scope of Review
The NRC performed an inspection of NextEras license renewal and aging management
activities to address concrete degradation due to the effects of ASR. The purpose of this
inspection was to determine whether the actions taken by NextEra since the previous
IP 71002 inspection in 2011 were adequate to manage the effects of aging in concrete
structures due to ASR at the Seabrook Station by meeting the following three objectives:
- To verify the applicants license renewal program, including supporting activities, are
planned or implemented in accordance with the requirements of 10 CFR 54 and the
applicants license renewal application.
- To verify the applicant has adequate programs planned or in place to implement
aging management for the structures, systems, and components that require an
aging management review.
- To verify the information and documentation required are retrievable, auditable and
consistent with the license renewal application and approved programs and
procedures.
Background
On May 25, 2010, NextEra submitted to the NRC its application for renewal of its operating
license for Seabrook Station, Unit No. 1 (ADAMS Accession Number ML101590099).
NextEra requested renewal of the operating license for an additional 20 years beyond the
current 40-year license, which expires on March 15, 2030. During preparations for license
renewal in the 2009 to 2010 timeframe, NextEra identified that the intrusion of moisture into
sections of walls in certain below-grade structures at the Seabrook Station could cause
potential degradation of some of the concrete as evidenced by pattern cracking. The
petrographic examination of concrete core samples subsequently confirmed that the pattern
cracking occurring in Seabrook Station structures was due to ASR. The reaction forms a gel
that can expand and cause micro-cracks in the concrete. The Seabrook Station was the
first nuclear power plant in the United States to identify the presence of the ASR in its
concrete structures.
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On April 8, 2011, the NRC completed a license renewal inspection (ML111360432) utilizing
NRC IP 71002 as part of the review process for the license renewal application. The
inspection was conducted by a team of NRC regional experts with materials and license
renewal backgrounds. The inspection team concluded scoping and screening of non-safety
related systems, structures, and components were implemented as required in 10 CFR 54.4(a)(2), and the aging management portions of the license renewal activities were
planned or implemented as described in the license renewal application. The team further
concluded that except for the ASR issue, the inspection results supported a conclusion of
reasonable assurance with respect to managing the effects of aging in the systems,
structures, and components identified in the application. The inspection team noted that
NextEra staff were developing an initial response to the aging effects of ASR and that
investigation and testing were ongoing. As a result, the inspection team was unable to
arrive at a conclusion about the adequacy of the aging management review for the ASR
issue.
Consistent with this conclusion, the NRC staff reviewing the license application designated
as Open Item, OI 3.0.3.2.18-1, in the Seabrook Station license renewal draft Safety
Evaluation Report (ML12160A374), NRC staff concerns that NextEra had not adequately
enhanced the Structures Monitoring Program to manage the effects of ASR. NextEra
communicated plans to submit additional information to the NRC to provide for an
acceptable program to manage the effects of ASR.
At an April 23, 2012, public meeting with NextEra, NRC staff discussed their focus on the
long-term operability of the affected structures. Subsequently, by letters dated May 3 and
May 10, 2012 (ML12125A022 and ML12131A479), NextEra described the actions it would
take to address the degraded conditions as well as to ensure that Seabrook Station
continued to meet its current licensing basis as a result of the ASR issue. The NRC issued
a Confirmatory Action Letter (CAL) to confirm the actions committed to by NextEra
(ML12125A172). The NRC conducted two team inspections that comprehensively reviewed
selected procedures and records, observed activities, and interviewed station personnel
regarding the adequacy of NextEra's actions to address the impact of ASR on reinforced
concrete structures, which was documented in inspection reports dated December 3, 2012
and August 9, 2013 (ML12338A283 and ML13221A172). Based on the reviews of
NextEras actions to complete these commitments, the NRC issued a CAL closure letter on
October 9, 2013 (ML13274A670). Further significant corrective actions were in progress at
the time of the closure letter, including a planned test program of ASR-affected large scale
concrete specimens at the University of Texas, Ferguson Structural Engineering Laboratory.
On September 3, 2013, the NRC documented in a mid-cycle performance review letter to
NextEra (ML13246A107) NRC plans to continue to provide focused oversight of the testing
being conducted at the Ferguson Structural Engineering Laboratory and the continual
assessment of ASR progression in the on-site Seabrook Station concrete structures. The
NRC inspection activities were conducted using focused Problem Identification and
Resolution samples in accordance with NRC IP 71152 on a semi-annual frequency. The
following table provides a list of these inspections completed to date:
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Inspection Report ADAMS
Date Number Accession
Number
01/30/2014 05000443/2013005 ML14030A509
05/06/2014 05000443/2014002 ML14127A376
02/06/2015 05000443/2014005 ML15037A172
08/05/2015 05000443/2015002 ML15217A256
02/12/2016 05000443/2015004 ML16043A391
05/06/2016 05000443/2016008 ML16127A155
02/08/2017 05000443/2016004 ML17040A220
08/14/2017 05000443/2017002 ML17227A018
02/12/2018 05000443/2017004 ML18043A821
05/14/2018 05000443/2018001 ML18134A222
During a plant tour on May 23, 2014, NRC inspectors identified several instances of large,
discrete cracks in the residual heat removal equipment vaults. The NRC issued a finding of
very low safety significance in an inspection report dated August 5, 2014 (ML14212A458)
because NextEra did not perform an adequate technical evaluation when it was determined
the crack sizes exceeded the quantitative limits specified in NextEra procedures. Later in
2015, NRC inspectors observed degraded seismic and fire seals that appeared to have
been caused by differential movement between adjoining concrete buildings. NextEra staff
initiated a root cause that confirmed some of the structures affected by ASR had evidence of
bulk expansion (macro-cracking and some reinforced concrete wall displacements) due to
the aggregate effect of induced micro-cracking. The bulk expansion due to ASR resulted in
building deformation and impacted some structures, systems, and components attached to
the adjoining structures as evident by deformed flexible conduit couplings and reduced
seismic isolation gaps. The building deformation (observed in structures such as the
residual heat removal equipment vaults and the containment enclosure building) and its
impact to equipment were considered a new phenomenon related to the effects of ASR, and
NextEra subsequently developed an additional plant-specific aging management program to
manage this effect.
In a report dated December 17, 2015 (ML15337A047), NRC staff from the Office of Nuclear
Reactor Regulation, Division of License Renewal, documented the results of an audit
performed at the Ferguson Structural Engineering Laboratory at the University of Texas at
Austin. The purpose of the audit was for staff to establish a clear understanding of
NextEras large-scale test program and its use as a technical basis for developing elements
of the plant-specific aging management program. Prior to the audit, the NRC staff issued
requests for additional information pertaining to various staff concerns with the current aging
management program. One of those concerns included addressing recent operating
experience concerning building deformation caused by bulk ASR expansion. Based on this
audit, the NRC staff found that additional information was still needed in order for the NRC
staff to complete its review of the aging management programs as part of the license
renewal application.
In February 2016, NextEra completed its testing of large-scale ASR-affected test specimens
at the Ferguson Structural Engineering Laboratory, and based on results from the testing
program, NextEra enhanced its Structures Monitoring Aging Management Program for both
the Alkali-Silica Reaction Monitoring and the Building Deformation Monitoring programs. On
August 9, 2016, the NRC received NextEra's updated license renewal application submittal
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which included these updates to the aging management programs (ML16224B079). The
NRC sent several requests for additional information to which NextEra subsequently
responded. Further NRR audits were conducted as documented in reports dated
December 21, 2016 (ML16333A247), and July 26, 2017 (ML17199T383). The NRC
completed an audit of the license renewal application in March 2018 and documented the
results in a site audit report (ML18135A046).
The inspectors recognized the significant passage of time between the previous license
renewal inspection and this current inspection with regard to issues outside of ASR.
Therefore, the inspectors coordinated with NRC staff in the Division of Materials and License
Renewal to review the license renewal application supplements and the annual update
letters submitted since the 2011 inspection to identify any significant changes that would
warrant re-inspection and inclusion in the scope of this IP 71002 inspection. No issues
requiring re-inspection were identified; therefore, the scope of this inspection was focused
on the review of the open item from the license renewal inspection conducted in 2011
related to managing the aging effects of ASR at the Seabrook Station.
INSPECTION RESULTS
Observation 71002
NextEra staff completed activities as part of a long-term corrective action plan to address the
aging effects of ASR to include identification, evaluation, structural monitoring and corrective
actions including modifications. A significant part of NextEras activities included completion
of a large-scale testing program to better understand the impact of ASR on structural
performance and enhancements to the on-site monitoring programs through the use of
various tools such as crack gauges and through-wall expansion measurements. The NRC
conducted previous inspections of NextEras testing program and periodic on-site visits to
review the ongoing structures monitoring program implementation and results, which were
documented in publicly-available NRC inspection reports. These inspections also provided
insights into staff review of Seabrook Stations License Amendment Request 16-03, "Revise
Current Licensing Basis to Adopt a Methodology for the Analysis of Seismic Category I
Structures with Concrete Affected by Alkali-Silica Reaction," that NextEra submitted on
August 1, 2016. The NRC verified during those previous inspections that operating
experience from testing and on-site observations at the Seabrook Station were appropriately
considered for input into applicable aging management programs.
During this license renewal inspection, the inspectors reviewed the following Seabrook
Station aging management programs: Structures Monitoring, Alkali-Silica Reaction, and
Building Deformation. The inspectors noted the programs were organized such that the
Alkali-Silica Reaction and Building Deformation Aging Management Programs were both
implemented under the Structures Monitoring Program. The Structures Monitoring Aging
Management Program is the parent program to monitor the condition of structures and
structural components within the scope of the Maintenance Rule and license renewal, such
that there is not a loss of intended safety function. The Alkali-Silica Reaction Aging
Management Program monitors cracking due to expansion and reaction with aggregates in
concrete structures to evaluate the impact of ASR on the structural strength and anchorage
capacity. The Building Deformation Aging Management Program monitors location-specific
criteria, based on initial crack measurements and a building-specific structural evaluation, to
evaluate the impact of deformation on the structural function. This program also monitors and
7
evaluates the impact to functionality of systems and components that are connected and/or
adjoining to the affected structures.
The inspectors reviewed Seabrook Stations procedures for monitoring and evaluating
reinforced concrete structures susceptible to ASR degradation to verify that parameters to be
monitored and monitoring frequencies specified were being implemented in accordance with
the license renewal application. For the ASR program, the inspectors reviewed a sample of
results from in-plane expansion measurements, which were trended using combined crack
indexing and embedded pins. The frequency was verified for Tier II locations (cracking > 0.5
mm/m) to be every 30 months and for Tier III locations (cracking > 1.0mm/m) to be every
6 months. The inspectors further verified that all Tier III locations were being monitored for
through-thickness expansion, measured via borehole extensometers. The inspectors also
verified the in-plane and through-thickness expansion for all structures remained below the
established limits described in the procedure and based on the results from NextEras
large-scale testing program.
For the Building Deformation program, the inspectors reviewed a sample of location-specific
monitoring criteria (e.g., in-plane strain rate, crack widths/lengths, structural dimensions,
equipment offsets) at the frequency established from the individual structural evaluations.
The inspectors noted that all ASR-affected structures were to receive a structural evaluation
and that several evaluations were in progress with an estimated completion date of
September 2018. Once a structural evaluation was performed for building deformation, the
monitoring frequency was established based on the limiting criteria from the ASR and Building
Deformation programs. For components impacted by structural deformation, the inspectors
reviewed a sample of results from walk downs conducted at a minimum frequency of every
2 years focused on features including, but not limited to, distorted flexible couplings,
non-parallel HVAC joints, distortions or tears in seals, crimped tubing, offset hanger rods, and
misaligned pipe flanges.
The inspectors performed detailed walk downs of portions of the following structures:
- A and B Residual Heat Removal Equipment Vaults;
- Fuel Storage Building;
- Containment Enclosure Ventilation Area.
The inspectors reviewed criteria from the applicable structures monitoring procedures as
described above to independently assess whether structural conditions and deficiencies such
as discrete cracks, pattern cracking, concrete pop-outs, scaling, spalling, water ingress,
coating separation or misalignment observed in these areas were previously identified by
NextEra staff and appropriately evaluated against the applicable acceptance criteria. The
inspectors accomplished this by comparing the results of their plant walk downs to the
records in the Seabrook Station structures monitoring program database for these particular
areas. The inspectors observed the database records included both quantitative
measurements and qualitative descriptions accompanied by dated photographic
documentation of the conditions by area. The inspectors independent walk downs and review
of the database records did not identify any deficiencies that were not previously identified
and evaluated by NextEra staff.
The inspectors further reviewed the condition of these areas as documented of the Seabrook
Station structures monitoring program database to verify the results of previous examinations,
8
including identified deficiencies, photographic records and corrective actions, were
documented, retrievable, and provided an auditable record of the conditions, trends and
action taken. Based on these reviews, the inspectors concluded that NextEra staff were
implementing their established processes in accordance with the plant procedures and
structural deficiencies were being appropriately tracked, trended, and dispositioned.
The inspectors identified the following observations that were discussed with NextEra staff:
1. The inspectors identified several instances where the aging management programs
docketed to the NRC as part of the license renewal application were not consistent with
Seabrook Stations on-site processes and procedures. For example, the docketed
Building Deformation Program in the license renewal application described the
consideration of moment redistribution and the 100-40-40 percent rule for a detailed
structural evaluation, however these methods were appropriately not utilized at Seabrook
Station or included in their implementing procedures. These differences between the
docketed aging management programs in the license renewal application and
implementing procedures reflected changes made to their procedures by NextEra staff as
a result of responses to NRC requests for information. These inconsistencies were also
identified during the NRC audit in March 2018, and required an update to the license
renewal application. The inspectors discussed the license renewal application documents
in question with NextEra staff and determined that NextEra staff was in the process of
making appropriate changes. Subsequent to the on-site inspection dates, NextEra
submitted the revised aging management programs for ASR and Building Deformation to
the NRC on May 18, 2018 (ML18141A785). The inspectors completed an in-office
inspection of the submittal and found the docketed and updated Structures Monitoring
Aging Management Programs to be consistent with the implemented processes and
procedures reviewed during the on-site inspection between April 30 and May 3, 2018.
2. The inspectors identified that raw data for the Invar rods located in the Residual Heat
Removal Vaults was being collected, but the data was not translated into units useful for
monitoring and trending (i.e., inches displacement). The rods were installed to aid in
measuring the vertical displacement of the vaults over a span of multiple building
elevations. The inspectors noted that vertical displacement of the vaults was a parameter
identified in Appendix C of the Structures Monitoring Program Manual with a threshold
limit requiring periodic monitoring. Based on discussions with NextEra staff, the
inspectors understood that there was an action being tracked (AR 02148021, Assignment
No. 22) to develop a procedure to correlate the recorded electronic data to unit length and
that the precision of the measurement technique would then be assessed against the
standard specified by the vendor. The inspectors concluded that the monitoring and
trending of the Invar data was not critical to detect degradation because a review of the
other monitored parameters for the residual heat removal vault would adequately detect
degradation in a timely manner.
Based on the previous NRC inspections of ASR-related issues completed to date and the
results of this follow-up license renewal inspection, the NRC concluded that for the ASR
issue, NextEra staff adequately performed scoping and screening of structures, systems, and
components as required in 10 CFR 54.4(a) and 54.21, respectively, and established aging
management programs as described in the license renewal application. The inspection
further concluded the documentation supporting the application was in an auditable and
retrievable form. The inspection results support the conclusion that there is reasonable
assurance that the effects of aging due to ASR in the Seabrook systems, structures, and
9
components will be managed through implementation of these programs as described in the
application for a renewed license currently under review by the NRC Office of Nuclear
Reactor Regulation.
EXIT MEETINGS AND DEBRIEFS
The inspectors verified no proprietary information was retained or documented in this report.
- On May 3, 2018, the inspectors debriefed the preliminary license renewal inspection results
to Mr. Eric McCartney, Regional Vice President, and other others of NextEra Staff.
- On June 27, 2018, the inspectors telephonically conducted an exit meeting of the license
renewal inspection results with Mr. Christopher Domingos, Site Director, and other members
of NextEra staff.
10
DOCUMENTS REVIEWED
Procedures
ES1807.031, Inservice Inspection Procedure Primary Containment Section XI IWL Program,
Revision 04
PI-AA-102-1001, Operating Experience, Revision 19
PI-AA-104-1000, Condition Reporting, Revision 17
SMP2.1, Structures Monitoring Inspections, Data Collection, and Evaluation, Revision 04
SMP3.1, ASR Monitoring Walkdowns, Data Collection, and Evaluation, Revision 02
SMP4.1, Building Deformation Monitoring Walkdowns, Data Collection, and Evaluation,
Revision 05
SMP5.1, Equipment Impacted by Structural Deformation Monitoring Walkdowns, Data
Collection, and Evaluation, Revision 03
SMPM, Structures Monitoring Program Manual, Revision 05 and 06
Condition Reports
00207755
00392697
02014325
02261159
02262440*
- initiated in response to inspection
Work Orders
40509687
40515022
40537747
40546928
Miscellaneous
2016 ASME IWL Examination Results, dated December 8, 2016
2016 IWL Containment Concrete Examination Plan, dated September 22, 2016
Extensometer Data of Through Thickness Expansions, dated May 2, 2018
FP 101154, March 2017 - Joint Width Measurements at Twenty-Five Seismic Isolation Joint
Locations, Revision 0
FP101203, 2017 Tier 2 Inspections - ASR Inspections and Cracking Index Measurements on
Concrete Structures, Revision 0
FP101204, 2017 Tier 2 Inspections - Measurements for ASR Expansion on Concrete
Structures, Revision 0
FP101229, December 2017 Tier 3 Inspections - ASR Inspections and Cracking Index
Measurements on Concrete Structures, Revision 0
FP101230, December 2017 Tier 3 Inspections - Measurements for ASR Expansion on
Concrete Structures, Revision 0
LRAP-ASR, Aging Management Program Basis Document for Alkali-Silica Reaction (ASR)
Monitoring Program, Revision 4
LRAP-BD, Aging Management Program Basis Document for Building Deformation Monitoring
Program, Revision 1
LRAP-S002, Aging Management Program Basis Document for ASME Section XI,
Subsection IWL, Revision 2
11
LRAP-S006, Aging Management Program Basis Document for Structures Monitoring Program,
Revision 1
SBK-L-17180, Supplement 58 - Revised Alkali-Silica Reactor Aging Management Program,
dated November 3, 2017
SBK-L-18028, Supplement 60 - Response to Final Requests for Additional Information for the
Safety Review of the Seabrook Station License Renewal Application - ASME Section XI,
Subsection IWL Program, dated February 28, 2018
SMP Program Health Reports from 1QTR 2013 to 2QTR 2018
Status of Building Deformation Structural Evaluations, dated 5-23-2018
Structures Monitoring Program Inspection Reports for A/B RHR Equipment Vaults, dated
April 30, 2018