ML17310A114

La - (External_Sender) Name Correction: Summary of August 24, 2017, Meeting with NextEra Energy Regarding License Amendment Request on Alkali Silica Reaction (CAC No. MF8260; EPID L-2016-LLA-0007)

ML17310A114
Person / Time
Site:	Seabrook
Issue date:	10/17/2017
From:	- No Known Affiliation
To:	Division of Operating Reactor Licensing
References
17-953-02-LA-BD01
Download: ML17310A114 (32)

Text

SeabrookLANPEm Resource From: Natalie Hildt Treat <natalie@c-10.org>

Sent: Tuesday, October 17, 2017 11:04 AM To: Poole, Justin

Subject:

[External_Sender] Name correction: Summary of August 24, 2017, Meeting with NextEra Energy Regarding License Amendment Request on Alkali Silica Reaction (CAC No. MF8260; EPID L-2016-LLA-0007)

Attachments: ML17278A748.pdf Hi Justin - would you please be so kind as to update the PDF on ADAMS to reflect our board member's name is Diane Teed, not Keenan?

Many thanks - Natalie

---

Forwarded message ----------

From: nrc_mail_3-1 Resource <nrc_mail_3-1.Resource@nrc.gov>

Date: Fri, Oct 13, 2017 at 3:32 PM

Subject:

Summary of August 24, 2017, Meeting with NextEra Energy Regarding License Amendment Request on Alkali Silica Reaction (CAC No. MF8260; EPID L-2016-LLA-0007)

To: Natalie Treat <natalie@c-10.org>

Subject:

Summary of August 24, 2017, Meeting with NextEra Energy Regarding License Amendment Request on Alkali Silica Reaction (CAC No. MF8260; EPID L-2016-LLA-0007)

ADAMS Accession No. ML17278A748 The attached document is being sent to you per your request to receive electronic mailings, if you wish to be removed follow the instructions below. The document is publicly available and will be accessible via the public web site Electronic Reading Room in the Agency Document Access and Management System (ADAMS),

http://www.nrc.gov/reading-rm/adams.html , generally within six days. To access this document use the ADAMS number provided in this email.

Documents containing proprietary or safeguards information are not publicly available and will not be sent using the electronic mailing system.

You are currently subscribed to seabrook as: natalie@c-10.org .

To unsubscribe: Please go to the NRC's public website http://www.nrc.gov/public-involve/listserver/plants-by-region.html Once at the site, type in your e-mail address in the space provided and check the box(es) that correspond to the list(s) you would like to unsubscribe from. Then click the Unsubscribe button.

1

or send an email to lyris@nrc.gov with the following information in the subject line unsubscribe seabrook natalie@c-10.org Natalie Hildt Treat Executive Director C-10 Research & Education Foundation, Inc.

44 Merrimac St., Newburyport, MA 01950 T: 978-465-6646 E: natalie@c-10.org W: c-10.org Click here to receive email updates from C-10.

The link ed image cannot be display ed. The file may hav e been mov ed, renamed, or deleted. Verify that the link points to the correct file and location.

2

Hearing Identifier: Seabrook_LA_NonPublic Email Number: 704 Mail Envelope Properties (CAM5hXJFbdRZhpuzMVuF8yETXo2g8jTzLgquPEqfunaoC0H+ayA)

Subject:

[External_Sender] Name correction: Summary of August 24, 2017, Meeting with NextEra Energy Regarding License Amendment Request on Alkali Silica Reaction (CAC No. MF8260; EPID L-2016-LLA-0007)

Sent Date: 10/17/2017 11:04:21 AM Received Date: 10/17/2017 11:05:04 AM From: Natalie Hildt Treat Created By: natalie@c-10.org Recipients:

"Poole, Justin" <Justin.Poole@nrc.gov>

Tracking Status: None Post Office: mail.gmail.com Files Size Date & Time MESSAGE 2608 10/17/2017 11:05:04 AM ML17278A748.pdf 2039182 Options Priority: Standard Return Notification: No Reply Requested: No Sensitivity: Normal Expiration Date:

Recipients Received:

Seabrook Station License Amendment Request Stage 3 Methodology Justin Poole, Project Manager, DORL, NRR Bryce Lehman, Structural Engineer, DE, NRR George Thomas, Senior Structural Engineer, DE, NRR

Agenda Issues with Current Stage 3 Methodology Staff Expectations for Methodology Path Forward Schedule Discussion 2

Stage 3 as Described in LAR Description in LAR of advanced techniques proposed to be used is high-level with no implementation details provided for staff to evaluate as a generic method of evaluation Includes methods whose implementation appear open to interpretation, with no specific applicability limitations, justification or acceptance criteria, and may be outside the design code (ACI 318-71)

LAR notes that analysis will demonstrate compliance with ACI 318-71 3

Staff Concerns with Stage 3 It is unclear how the methodology as described in the LAR could be consistently applied and similar results obtained

- Significant decisions in the Containment Enclosure Building (CEB) calculation appear to be based on engineering judgement

- Stage 3 uses iterative processes with no clear limitations 4

Staff Concerns with Stage 3 Review of Containment Enclosure Building (CEB) calculation identified several general issues:

- ACI 318-71 requirements for moment redistribution do not appear to be met or justified; approach used does not appear to be supported by accepted concrete codes

- Acceptance criteria are not provided for the structural adequacy of sections to develop a plastic hinge

- A limit on moment redistribution iterations is not provided

- No guidance is provided on determining the threshold factor or under what circumstances it can be modified

- No evaluation of serviceability limit state included under normal service load conditions that include ASR 5

Staff Expectations for Methodology The LAR or UFSAR mark-up should include sufficient detail to allow qualified engineer to follow the process through any Stage 3 calc

- How ACI 318-71 requirements will be met and/or justification for alternatives and requirements that are not met

- Guidance/criteria on when proposed analysis techniques and methods can be used

- Limits on the use of iterative processes

- Identified rebar strain limits under normal service conditions including ASR load 6

Path Forward:

Potential LAR Supplement Potential LAR supplement options:

- Update LAR to include detailed, consistently applicable methodology; staff will review a sample of completed calculations

- Approval of partial methodology (Stage 1 & 2); all final Stage 3 evaluations for NRC review and approval

- Other options?

Approach is up to NextEra 7

Impacts on Schedule Staff intends to review a sampling of completed Stage 1, 2 and 3 analyses

- Sampling dependent on analysis complexity and issues identified Schedule dependent on analyses availability

- Analyses should be approved and incorporated by NextEra prior to NRC review 8

Questions?

9

Seabrook Station License Amendment Request 16-03 ASR Structural Evaluation Methodology Ken Browne, Mike Collins 24 August 2017

NextEra Energys nuclear fleet is 4th largest in MW generation and number of reactors in the U.S.

Acquired: 2002 Seabrook (New Hampshire) 1,245 MWe Acquired: 2007 Point Beach (Wisconsin) 1,193 MWe St. Lucie (Florida) 2,000 MWe Acquired: 2006 Duane Arnold (Iowa) Turkey Point 615MWe (Florida) 1,600 MWe NextEra Energys nuclear plants represent approximately 27 percent of our generation 2

The foundation for everything we do are the Values and Core Principles of our Nuclear Excellence Model 3

Objective

• Understand staff expectations for methodology

• Address comments on LAR Stage 3 methodology

• Discuss methodology document

• Show consistency of applied methodology

• Schedule & path forward 4

Overview of ASR Evaluation Process

• Stage 1, 2, and 3 analyses License Amendment Request

• Material properties

• Repeatable process for stage Methodology Document 1, 2, and 3

• Decision points for analysis

• Demand calculations Structural Analysis &

• Compliant to ACI 318-71, Evaluation ASME and UFSAR acceptance criteria

• Establish design margin Threshold Limits Structures Monitoring

• Threshold limits Program

• ASR expansion limits

• Administrative limits 5

Overview of Methodology Document

• Overview

• Codes and Standards

• Materials

• Load and load combinations

• Analysis

- Stage One and Stage Two

- Stage Three Correlation of model to field conditions Decision points

• Acceptance Criteria

• ASR Threshold Limits and Monitoring 6

Stage Three Evaluation Process Field observations & FEA Model Distress &

Sustained measurements Deformation Loads Cracking Concrete Backfill Pressure Moment Redistribution

• Is cracking observed?

• Is backfill confined?

• Is there a self-relieving

• Is there softening in the condition?

• Is cracking limit confinement?

• Is there a localized Decisions exceeded?

• Is scaling needed to moment exceedance?

match field condition?

• Does structural configuration conform to ACI 318-71 Section 8.6?

Factored Loads

• Flexural cracking limited

• Limit to overburden

• Limit to ACI 318-71 8.6 to ACI 318-71 pressure for conforming structures

• Axial tension and shear

• Limit to strength of

• Confirm with alternative cracking stiffness limits confinement analysis Limits of use

• Limit to field observations Demand-to-capacity Acceptance Criteria ratio 7

Evaluation

Co n tro l Me & Die s el ch. Pen Co o l i . & MS ng Tow er FW -W E lect ri c a Consistency of Co l Ma n ho ta ke n d en s ate les E q ui p m St or a ge Co n en t Ha t ch Tan k ir In tain me nt Methodology Ste am Ge CE VA n . B low d ow e-u E le n pA ct ri c al Tu n Co n tain nel CE Ma RH me n t I nte B k R FS B r nals Stage 3 3 3 3 3 3 3 3,2,1 2 1 1 1 1 1 1 LOADS AND LOAD COMBINATIONS Load Combinations 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 Containment NA NA NA NA NA NA NA NA NA NA 9 NA NA NA NA Containment Internal Structures NA NA NA NA NA NA NA NA NA NA NA NA NA NA 9 Other Seismic Category I Structures 9 9 9 9 9 9 9 9 9 9 NA 9 9 9 NA ANALYSIS Selection of Starting Stage 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 Stage One Analyses NA NA NA NA NA NA NA 9 NA 9 9 9 9 9 9 Stage Two Analyses NA NA NA NA NA NA NA 9 9 NA NA NA NA NA NA Stage Three Analyses 9 9 9 9 9 9 9 9 NA NA NA NA NA NA NA Field Observations to Support Stage Three Analyses 9 9 9 9 9 9 9 9 NA NA NA NA NA NA NA Non-ASR Demands for Stage Three Analyses 9 9 9 9 9 9 9 9 NA NA NA NA NA NA NA ASR Demands for Stage Three Analyses 9 9 9 9 9 9 9 9 NA NA NA NA NA NA NA ASR Expansion of Structural Components 9 9 9 9 9 9 9 9 NA NA NA NA NA NA NA ASR Expansion of Concrete Backfill 9 NA 9 9 9 9 NA NA NA NA NA NA NA NA NA Correlation of Model with Field Conditions 9 9 9 9 9 9 9 9 NA NA NA NA NA NA NA Refined Analytical Methods 9 9 9 9 9 9 9 9 NA NA NA NA NA NA NA Use of Cracked Section Properties in Stage Three Analyses NR 9 9 9 9 9 9 9 NA NA NA NA NA NA NA Use of Moment Redistribution in Stage Three Analyses 9 NR 9* NR NR NR NR 9* NA NA NA NA NA NA NA Factored Load Calculation 9 9 9 9 9 9 9 9 NA NA NA NA NA NA NA ACCEPTANCE CRITERIA Acceptance Criteria for Containment NA NA NA NA NA NA NA NA NA NA 9 NA NA NA NA Acceptance Criteria for Other Seismic Category 1 Structures 9 9 9 9 9 9 9 9 9 9 NA 9 9 9 9 Impact of ASR on Code of Record Acceptance Criteria 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 Acceptance Criteria for Isolation Gaps 9 NA 9 9 9 9 NA NA NA 9 9 9 9 9 NA Acceptance Criteria for Foundations 9 9 9 9 9 9 9 9 9 9 9 9 9 9 NA Acceptance Criteria for Stability 9 9 9 9 9 9 9 9 9 9 9 9 9 9 NA ASR THRESHOLD LIMITS AND MONITORING Methodology to Account for Potential Future ASR Expansion 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 ASR Threshold Limits and Monitoring for Stage One Structures NA NA NA NA NA NA NA NA NA 1.5 1.8 3.5 3.0 3.0 9 ASR Threshold Limits and Monitoring for Stage Two Structures NA NA NA NA NA NA NA NA 1.6 NA NA NA NA NA NA ASR Threshold Limits and Monitoring for Stage Three Structures 1.2 1.4 1.2 9 9 9 9 9 NA NA NA NA NA NA NA 8

Threshold Monitoring Methodology Structural Evaluation Identify minimum threshold factor Yes Perform monitoring. Yes Consider Structural Further analysis Is threshold limit Modification approached?

No Continue Monitoring Re-evaluate using same methodology, Identify new threshold factor 9

Building Deformation Analyses (1 of 2)

Structure Schedule Percent Complete Condensate water storage tank Complete 100%

Containment enclosure building Complete 100%

Containment enclosure ventilation area Complete 100%

Containment structure Complete 100%

Equipment hatch missile shield Complete 100%

Steam generator recovery blowdown bldg. Complete 100%

Control room make-up air intake Complete 100%

Electrical cable tunnels Complete 100%

Pre-action valve building 3Q2017 80%

RHR equipment vault Complete 100%

Containment internal structures 3Q2017 80%

Main steam and feed water east pipe chase 3Q2017 50%

Hydrogen recombiner structure Safety-related electrical duct banks and manholes 1Q2018 40%

Emergency feedwater pump building 3Q2017 10%

Fuel storage building 3Q2017 60%

Structures that are/expected to be Stage 3 10

Building Deformation Analyses (2 of 2)

Structure Schedule Percent Complete Control Building 4Q2017 10%

Diesel Generator Building Mechanical Penetration Personnel hatch area 4Q2017 30%

Main steam and feed water west pipe chase Primary auxiliary building 4Q2017 10%

Service water cooling tower incl. switchgear rooms 1Q2018 Service water access (inspection) vault 1Q2018 Circulating water pumphouse (below el. 21')

2Q2018 Service water pumphouse Piping (RCA) Tunnels 2Q2018 Tank farm area 2Q2018 Waste processing building 2Q2018 Structures that are/expected to be Stage 3 11

Discussion with NRC Staff 12

Wrap Up

• The importance to establish a repeatable methodology with limits is understood

• A consistent methodology is being applied in the structural evaluations

• A methodology document will be submitted Next Steps

• Submit methodology document

• Respond to issued RAIs

• Maintain communications with NRC staff 13