ML093370203

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Summary of Public Meeting for Wolf Creek Generating Station
ML093370203
Person / Time
Site: Wolf Creek Wolf Creek Nuclear Operating Corporation icon.png
Issue date: 12/03/2009
From: Geoffrey Miller
NRC/RGN-IV/DRP/RPB-B
To: Muench R
Wolf Creek
References
Download: ML093370203 (38)


Text

UNITE D S TATES NUC LEAR RE GULATOR Y C OMMIS SI ON R EG IO N I V 6 12 EAST LAMAR BLVD , SU ITE 4 00 AR L I N GTON , TEXAS 7 601 1- 4125 December 3, 2009 Mr. Rick A. Muench, President and Chief Executive Officer Wolf Creek Nuclear Operating Corporation P.O. Box 411 Burlington, KS 66839

SUBJECT:

SUMMARY

OF PUBLIC MEETING FOR WOLF CREEK GENERATING STATION

Dear Mr. Muench:

This refers to the public meeting conducted at the NRC Region IV Office in Arlington, Texas, on November 30, 2009, to discuss the initiatives to improve performance at the Wolf Creek Generating Station.

Topics discussed during the meeting included the recent problem identification and resolution improvement progress and the status of the emergency service water system Wolf Creek Generating Station. Members of the public present at the meeting or on a telephonic bridge and were allowed to ask questions and comment on the proceedings.

In accordance with 10 CFR 2.390 of the NRCs Rules of Practice, a copy of this letter and its enclosure will be made available electronically for public inspection in the NRC Public Document Room or from the Publicly Available Records (PARS) component of NRCs 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).

Should you have any questions concerning this matter, I will be pleased to discuss them with you.

Sincerely,

/RA/

Geoffrey Miller, Chief Project Branch B Division of Reactor Projects Docket: 50-482 License: NPF-42

Enclosures:

1. Attendance List
2. Presentation Slides

Wolf Creek Nuclear Operating Co. Electronic distribution by RIV:

Regional Administrator (Elmo.Collins@nrc.gov )

DRP Director (Dwight.Chamberlain@nrc.gov)

DRP Deputy Director (Anton.Vegel@nrc.gov )

DRS Director (Roy.Caniano@nrc.gov )

DRS Deputy Director (Troy.Pruett@nrc.gov)

Senior Resident Inspector (Chris.Long@nrc.gov)

Branch Chief, DRP/B (Geoffrey.Miller@nrc.gov)

Senior Project Engineer, DRP/B (Rick.Deese@nrc.gov)

Team Leader, DRP/TSS (Chuck.Paulk@nrc.gov)

DRS STA (Dale.Powers@nrc.gov )

OEDO RIV Coordinator (Leigh.Trocine@nrc.gov)

ROPreports Wolf Creek Site Secretary (Shirley.Allen@nrc.gov)

SUNSI Review Completed: __D__ADAMS: Yes G No Initials: GM Publicly Available G Non-Publicly Available G Sensitive Non-Sensitive SPE:DRP/PBB C: DRP/PBB PAJayroe GBMiller

/RA/ /RA/

12/3/2009 12/3/2009 OFFICIAL RECORD COPY T=Telephone E=E-mail F=Fax

Vice President Operations/Plant Manager Wolf Creek Nuclear Operating Corporation P.O. Box 411 Burlington, KS 66839 Jay Silberg, Esq.

Pillsbury Winthrop Shaw Pittman LLP 2300 N Street, NW Washington, DC 20037 Supervisor Licensing Wolf Creek Nuclear Operating Corporation P.O. Box 411 Burlington, KS 66839 Chief Engineer Utilities Division Kansas Corporation Commission 1500 SW Arrowhead Road Topeka, KS 66604-4027 Office of the Governor State of Kansas Topeka, KS 66612-1590 Attorney General 120 S.W. 10th Avenue, 2nd Floor Topeka, KS 66612-1597 County Clerk Coffey County Courthouse 110 South 6th Street Burlington, KS 66839 Chief, Radiation and Asbestos Control Section Bureau of Air and Radiation Kansas Department of Health and Environment 1000 SW Jackson, Suite 310 Topeka, KS 66612-1366 Chief, Technological Hazards Branch FEMA, Region VII 9221 Ward Parkway Suite 300 Kansas City, MO 64114-3372

Wolf Creek Nuclear Operating Corporation Update on Initiatives to Improve Performance (11-30-2009) 1

Introduction Matt Sunseri 2

Wolf Creek Team

  • Matt Sunseri - Vice President Operations

& Plant Manager

  • Terry Garrett - Vice President Engineering
  • Steve Henry - Manager Operations
  • Steve Koenig - Manager Corrective Action
  • Rick Muench - President & CEO 3

Introduction

  • Early in 2009 Wolf Creek implemented significant changes to our Corrective Action Program (CAP)
  • We have improved plant safety in several areas with our new approach

- Training

- Supplemental Worker Performance

- Offsite Power Availability 4

Introduction

  • Most recently we have faced new challenges

- Auxiliary Spray Piping

- Essential Service Water (ESW) Piping

  • Today we will discuss ESW as a case study in using our new CAP approach
  • We recognize that we will have more improvement opportunities 5

Introduction

  • Some of our Condition Report (CR) evaluations are not as strong as they should be and we will discuss that with you today
  • Lastly, we will discuss our continued oversight of the CAP 6

ESW Pipe Corrosion Issues Terry Garrett 7

ESW Piping Situation

  • Wolf Creek has experienced minimal through wall leaks in above ground ESW piping in the first 25 years of operation

- Increased through wall leaks occurred in 2009 prior to Refuel (RF) 17

  • After second leak in 2009, an apparent cause evaluation (ACE) was conducted

- Corrective actions initiated to limit recurrence include increased inspections, monitoring, and accelerated planned piping replacements

  • In all cases structural integrity has been demonstrated with wide margins 8

ESW Piping Corrosion Mechanisms

  • Through wall pipe leaks have occurred due to five corrosion mechanisms
  • Dominant mechanism is under tuberculation pitting corrosion
  • Tuberculation is the formation of localized corrosion products scattered over the surface in the form of knob-like mounds called tubercles 9

Corrosion of 30 ESW Piping 10

ESW Piping Corrosion Mechanisms

  • There is no definitive determination that biological mechanisms (MIC) are instrumental in the observed corrosion
  • Tuberculation formation may involve a microbiological mechanism, but biological activity is not required
  • Corrosion rates estimated from Wolf Creek experience include any effects of MIC 11

ESW Piping Corrosion Apparent Cause Evaluation

  • Corrective actions include:

- Increase the monitoring and inspections starting in RF17 (OE from Callaway used to help define)

- Update our Lake Water Systems Structural Integrity Program

- Establish a pro-active piping replacement strategy

  • Cause evaluation will be updated to include information from augmented inspections, sample analysis 12

Refuel 17 - Major B Train Outage

  • Performed planned ultrasonic testing (UT) examinations -12 on B train, 4 on A train
  • Performed planned underground leakage test on B train
  • Performed augmented exams using TesTex technology and UT
  • Implemented repairs 13

Refuel 17 Augmented ESW Piping Exams

  • Inspected 10 different piping segments on B train ESW

- 217.5 linear feet of 30 inch piping (1,700 ft2)

- 94 linear feet of 8 inch piping (212 ft2)

- 22 linear feet of 4 inch pipe (25 ft2)

  • The 217.5 linear feet of 30-inch pipe (~60%

of accessible B Train) includes some of the piping most susceptible to pitting type corrosion 14

Refuel 17 Augmented ESW Piping Exams

  • 13 pitted locations on 30-inch pipe identified

- Structural integrity of the 13 locations was met with large margin

- None of the 13 pitted locations required repair in Refuel 17

- All identified locations will be monitored whether or not repaired

- 5 remaining locations will be monitored and repaired 15

Refuel 17 ESW Pipe Weld Corrosion

  • One example of preferential corrosion along a circumferential weld was discovered
  • Identified during repair of a through wall leak that occurred during the previous operating cycle
  • The only identified incidence of preferential attack along a weld at Wolf Creek 16

Refuel 17 ESW Pipe Weld Corrosion

  • Localized corrosion extended approximately 5.5 inches around the pipe circumference
  • Metallurgical and chemical analysis do not indicate that there is a systemic problem
  • Examined 10 similar welds with no instances of similar corrosion found 17

ESW Piping Future Plans

  • The following are our current plans and the plans may be adjusted based on future inspections, analysis, or operating experience.

18

Future Plans Refuel 18 - A Train Outage

  • ESW underground leakage test on A train
  • ESW A train piping augmented examinations
  • ESW piping replacements under consideration:

- 30 A train supply/return lines in basement of Control Building (contingent on inspection) 19

Future Plans Refuel 19 - B Train Outage

  • Perform examinations using TesTex technology on B train piping
  • ESW piping replacements under consideration:

- 30 B train supply/return lines in basement of Control Building 20

Future Plans Cycle 20 / Refuel 20

  • Run new buried piping for ESW train A and train B
  • Refuel 20 (or 14 day TSEO - needs NRC approval)

- Make connections of new buried ESW piping to place in service 21

Evaluation Improvement Progress Steve Henry 22

Previously Completed Actions

  • Early 2009 revised the CAP Evaluation Process

- New CAP structure has five levels of significance based on risk:

  • Incident Investigation Team (IIT)
  • Root Cause Evaluation (RCE)
  • Apparent Cause Evaluation (ACE)
  • Basic Low Level Evaluation (BLL)

- ACEs require use of analysis tools

- MORT established for management and organizational contributors 23

Previously Completed Actions

  • Conducted Training

- Root Cause Training for Performance Improvement Group and selected line personnel (22 trained in RCE)

- Apparent Cause Training for selected personnel (51 trained in ACE)

- Added continuing training for Root Cause and Apparent Cause evaluators

- Leadership Team alignment training

- Corrective Action Program Coordinators (CAPCOs) trained in root cause analysis and trending 24

Evaluation Improvement -

Going Forward

  • CAP self assessment conducted in September 2009 - Extent of condition (EOC) while better, still needs improvement
  • Common Cause evaluation in progress for P.1(c) on 2009 3rd Qtr Integrated Inspection Report

- EOC is an area needing improvement, and while a couple of these are latent issues, WCNOC is concerned with current performance 25

Evaluation Improvement -

Going Forward

  • Immediate actions to address EOC concerns:

- All level 4 basic evaluations are being reviewed by qualified root cause evaluators for quality of evaluation, extent of condition, and to evaluate appropriate corrective actions are taken

- Additional training focused on EOC is being developed for root cause evaluators, apparent cause evaluators, and management personnel

- Identifying and communicating good examples of EOC to site personnel

- Screening Review Team and Senior Leadership Review Team reviews ensure important issues receive proper attention. Reviews continued reviews during Refueling Outage 17.

26

Evaluation Improvement -

Going Forward

  • Improving our EOC evaluations

- ESW piping leaks

- Pressurizer auxiliary spray line outer diameter stress corrosion cracking

- Fuse holder issues, replaced in RF17

- August loss of offsite power event, EOC taken beyond Wolf Creek switchyard 27

CAP Metrics Steve Koenig 28

CR/WR Initiation Rates CR/WR Initiation Rates CRs ID's by Others CRs WRs Linear (CRs) 8000 7000 6000 5000 4000 3000 2000 1000 0

2005 2006 2007 2008 2009 YTD 29

Timeliness of Evaluation C R E v a lu a t io n T im e lin e s s Root Cause Ap p a r e n t C a u s e B a s i c E va l F i n d & F i x Goal 90 80 70 60 50

  1. of Days 40 30 20 10 0

2005 2006 2007 2008 2 0 0 9 YT D 30

Evaluation Quality CR Evaluation Quality Root Cause Apparent Caus e CREST 100%

90%

80%

70%

60%

50%

40%

30%

20%

10%

0%

2005 2006 2007 2008 2009YTD 31

Trend and Common Cause CRs Trend and Common Cause CRs Trend CRs Common Cause CRs 60 55 50 45 40 35 30 25 20 15 10 5

0 2007 2008 2009YTD 32

Closing Remarks Rick Muench 33

Comments and Questions 34