ML12179A447

6/18/2012 Meeting Summary for Augmented Inspection Team Exit Meeting with Southern California Edison Co

ML12179A447
Person / Time
Site:	San Onofre
Issue date:	06/26/2012
From:	Greg Werner NRC/RGN-IV/DRS/PSB-2
To:	Peter Dietrich Southern California Edison Co
vlm/Werner G
References
Download: ML12179A447 (8)

Text

UNITED STATES NUCLEAR REGULATORY COMMISSION REGION I V 1600 EAST LAMAR BLVD ARLINGTON, TEXAS 76011-4511 June 26, 2012 Mr. Peter Dietrich Senior Vice President and Chief Nuclear Officer Southern California Edison Company San Onofre Nuclear Generating Station P.O. Box 128 San Clemente, CA 92674-0128

SUBJECT:

MEETING

SUMMARY

FOR AUGMENTED INSPECTION TEAM EXIT MEETING WITH SOUTHERN CALIFORNIA EDISON COMPANY

Dear Mr. Dietrich:

On June 18, 2012, NRC personnel met with representatives of Southern California Edison at the San Juan Capistrano Community Center Community Hall, located in San Juan Capistrano, California to present the Augmented Inspection Team exit issues and observations.

In accordance with 10 CFR 2.390 of the NRCs Rules of Practice, a copy of this letter and its enclosure will be available electronically for public inspection in the NRC Public Document Room or from the Publicly Available Records (PARS) component of NRC's document system (ADAMS). ADAMS is accessible from the NRC Web site at http://www.nrc.gov/reading-rm/adams.html (the Public Electronic Reading Room).

Sincerely,

/RA/

Gregory Werner, Chief Plant Support Branch 2 Division of Reactor Safety Docket Nos. 0500050361, 0500050362 License Nos. NPF-10, NPF-15

Enclosure:

1. NRC Presentation

2. Southern California Edison Presentation Electronic Distribution for SONGS

ML12179A447 SUNSI Rev Compl. Yes No ADAMS Yes No Reviewer Initials GEW Publicly Avail Yes No Sensitive Yes No Sens. Type Initials GEW C:PSB2 PAO RSLO C:PSB2 GEWerner VLDricks WAMaier GEWerner

/RA/ /RA/ /E/ /RA/

6/20/2012 6/21/12 6/26/12 6/26/2012

NRC PRESENTATION San Onofre Nuclear Generating Station Augmented Inspection Team Purpose of Todays Meeting Public Exit Meeting Present the Status of the Augmented Inspection Discuss Activities Going Forward Answer Questions from the Audience Nuclear Regulatory Commission - Region IV June 18, 2012 1 2 Agenda NRC Representatives Introduction Augmented Inspection Team Decision Elmo Collins, Regional Administrator, Region IV Augmented Inspection Team Charter Thomas Blount, Acting Director, Division Reactor NRC Discussion on Augmented Inspection Status Safety Licensee Response to AIT Status Path Forward Greg Werner, Branch Chief , AIT Team Lead NRC Closing Remarks Greg Warnick, Senior Resident Inspector Question and Answer Session 3 4 NRC Representatives (Cont) SONGS Representatives Michele Evans, Director, Division of Operating Reactor Licensing Peter Dietrich, Senior Vice President and Chief Ryan Lantz, Branch Chief, Region IV Nuclear Officer, SONGS, SCE Victor Dricks, Senior Public Affairs Officer, Region IV John Reynoso, Resident Inspector, AIT Team Member Douglas Bauder, Vice President and Station Manager, Emmett Murphy, Senior Materials Engineer, Office of Nuclear SONGS, SCE Reactor Regulation, AIT Team Member Carl Thurston, Reactor Systems Engineer, Office of Research, Thomas Palmisano, Vice President of Nuclear AIT Team Member Engineering, Projects and Site Support, SONGS, SCE Joel Rivera-Ortiz, Senior Reactor Inspector, Region II, AIT Team Member Michael Bloodgood, Operations Engineer, Region IV 5 6 Enclosure 1

NRC PRESENTATION NRC Opening Remarks Steam Generator Tube Leak Actual tube leak was of minor safety significance.

Elmo Collins, Regional Administrator , Region IV Offsite radiation release was minimal.

Thomas Blount, Acting Director, Division of Reactor Safety The plant operators responded properly and minimized the release.

8 7

AIT Decision Management Directive 8.3

- Pre-Planning

- Criteria

- NRC Response 9 10 AIT Charter AIT Issues and Observations Team Members - 7 inspectors/engineers from 5 NRC offices Eight tubes failed pressure testing.

Key Objectives SONGS used multiple independent consultants and S/G manufacturers.

Additional information and observations provided by the resident inspectors 11 12 Enclosure 1

NRC PRESENTATION AIT Issues and Observations (cont) AIT Follow-up Items Ten items identified for follow-up:

Mitsubishis thermal/hydraulic computer simulation 1. Post trip/transient procedure model did not accurately predict the behavior of the

2. Evaluation and disposition of numerous steam and water in the steam generators.

Unit 3 loose parts monitor alarms

3. Retainer bar design not evaluated for Manufacturing differences between the steam vibration impacts generators contributed to the difference in tube

4. Evaluation of and control of Unit 3 divider plate degradation.

repair

5. Unit 3 steam generator shipping requirements 13 14 AIT Follow-up Items (cont) AIT Summary

• The NRC understands the steam generator thermal

6. Lack of tube bundle support for steam hydraulic conditions that resulted in the tube generators during shipment degradation.

7. Evaluation and disposition of shipping accelerometer data

• The thermal hydraulic conditions were not accurately predicted during design.

8. 50.59 evaluation

9. Control of manufacturing differences

• Additional actions to fix and prevent any additional tube-to-tube degradation due to excessive vibration

10. Adequacy of Mitsubishis computer simulation are being evaluated and developed. The NRC has model additional inspections to perform.

• The NRC will take as much time as needed to 15 ensure the safety of the public. 16 Path Forward - Key NRC Activities SONGS Response

• Continue review of steam generator tube wear

• Confirmatory Action Letter inspections Peter Dietrich

• Augmented Inspection followup inspection Senior Vice President

• Additional public meetings and

• NRC decision about the acceptability of the resumption of power operations Chief Nuclear Officer

• Routine process to recommend improvements to the inspection program 17 18 Enclosure 1

NRC PRESENTATION NRC Closing Remarks Elmo Collins 15 Minute Break Regional Administrator Region IV 19 20 Contacting the NRC

• Report an emergency (301) 816-5100 (24/7 NRC Headquarters Operation Center) (call collect)

• Report a safety concern:

Questions and Answers (800) 695-7403 (Toll-free Safety Hotline)

Allegation@nrc.gov

• General information or questions www.nrc.gov

• Victor Dricks, Public Affairs Officer, RIV 817-200-1128 Victor.Dricks@nrc.gov 21 22 Enclosure 1

SOUTHERN CALIFORNIA EDISON PRESENTATION SONGS EXCELLENCE 2012 SONGS EXCELLENCE 2012 Southern California Edison Commitment We operate San Onofre Nuclear Generating Station (SONGS) safely and reliably to the highest standards to protect the health and safety of the public and our employees Steam Generator Recovery Update We will not restart either Unit 2 or Unit 3 until we Nuclear Safety in Action and the NRC are satisfied it is safe to do June 18, 2012 SONGS EXCELLENCE 2012 SONGS EXCELLENCE 2012 Pressurized Water Reactor Layout Current Status

• Unit 2 Status:

- Shutdown on Jan. 9 for routine refueling and maintenance outage &

reactor vessel head replacement

• Unit 3 Status:

- Operators safely shutdown Unit 3 after steam generator tube leak identified on January 31

- Shared learning with industry 3 4 SONGS EXCELLENCE 2012 SONGS EXCELLENCE 2012 Steam Generator Cut-Away Elevation View Actions Taken to Date

• Discovered unexpected tube-to-tube wear in limited portions of Unit 3 steam generators

• Deferred Unit 2 restart pending investigation

• Assembled team of experts to inform, assist and challenge

• Completed extensive tests and analysis on both units in all steam generators to support determining cause 5 6 Enclosure 2

SOUTHERN CALIFORNIA EDISON PRESENTATION SONGS EXCELLENCE 2012 SONGS EXCELLENCE 2012 Technical Expertise Supporting SCE Cause of Unexpected Tube-to-Tube Wear

• Mitsubishi Heavy

• AREVA Industries

• Specific mechanism is Fluid Elastic Instability causing excessive tube vibration

• Westinghouse

• B&W Canada - Most excessive wear occurring in limited area of Unit 3 steam generators

• This is due to:

• High steam flow velocities

• MPR Associates

• EPRI

• Very dry steam

• Inadequate tube support structure in the U bend region for the tubes experiencing the wear

• Other industry personnel, recognized academics and specialized consultants 7 8 SONGS EXCELLENCE 2012 SONGS EXCELLENCE 2012 Next Steps

• Follow up on Augmented Inspection Teams additional requests

• Implement our corrective actions

• Develop additional information as stated in Confirmatory Action Letter

• Continue work to develop intermediate and long term solutions

- Will require extensive analysis, mock-ups and testing There is no timeline on safety 9 10 Enclosure 2