ML14141A640

NRR E-mail Capture - NRC Pre-application Presentation for June 3, 2014 Meeting

ML14141A640
Person / Time
Site:	Comanche Peak
Issue date:	05/21/2014
From:	Ervin-Walker T Luminant Generation Co
To:	Balwant Singal Division of Operating Reactor Licensing
References
MF3909, MF3910
Download: ML14141A640 (21)

Text

NRR-PMDAPEm Resource From: Ervin-Walker, Tamera [Tamera.Ervin-Walker@luminant.com]

Sent: Wednesday, May 21, 2014 1:37 PM To: Singal, Balwant Cc: Hope, Timothy

Subject:

RE: NRC Pre-application presentation for June 3, 2014 meeting.

Attachments: Luminant XST1A Pre-Application Meeting Presentation.pdf

Balwant, I must not have attached the presentation yesterday, My apologies, Tamera From: Ervin-Walker, Tamera Sent: Tuesday, May 20, 2014 2:55 PM To: 'balwant.singal@nrc.gov'

Subject:

NRC Pre-application presentation for June 3, 2014 meeting.

Confidentiality Notice: This email message, including any attachments, contains or may contain confidential information intended only for the addressee. If you are not an intended recipient of this message, be advised that any reading, dissemination, forwarding, printing, copying or other use of this message or its attachments is strictly prohibited. If you have received this message in error, please notify the sender immediately by reply message and delete this email message and any attachments from your system.

1

Hearing Identifier: NRR_PMDA Email Number: 1301 Mail Envelope Properties (8A564D9C9FEAEB43B29086244AA99370EF2D)

Subject:

RE: NRC Pre-application presentation for June 3, 2014 meeting.

Sent Date: 5/21/2014 1:37:04 PM Received Date: 5/21/2014 1:38:43 PM From: Ervin-Walker, Tamera Created By: Tamera.Ervin-Walker@luminant.com Recipients:

"Hope, Timothy" <Timothy.Hope@luminant.com>

Tracking Status: None "Singal, Balwant" <Balwant.Singal@nrc.gov>

Tracking Status: None Post Office: SDPRAPPEMBW01.tceh.net Files Size Date & Time MESSAGE 813 5/21/2014 1:38:43 PM Luminant XST1A Pre-Application Meeting Presentation.pdf 1113876 Options Priority: Standard Return Notification: No Reply Requested: No Sensitivity: Normal Expiration Date:

Recipients Received:

Comanche Peak Modification of Offsite Power Supplies to Improve Reliability June 3, 2014

Introductions

Tom McCool VP Engineering and Support Tim Hope Manager Regulatory Affairs Todd Evans Project Manager Tamera Ervin-Walker Principal Engineer Nuclear Nathan Larson Risk & Reliability Engineer 1

Luminant Pre-Application Meeting Agenda

• Purpose

• Modification Background

• Cut Cable Event

• Modification Completion Plan

• Risk Management

• License Amendment Request

• Closing Remarks 2

Purpose Meeting

• Inform Staff of Luminants planned deterministic LAR submittal for a one-time, extended, offsite power Technical Specification (TS)

Completion Time (CT)

Modification

• Facilitate connection of alternate Startup Transformer (ST) XST1A to 1E (Safeguards) buses within TS 3.8.1 CT of 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />

• Improvement in plant design for XST1 failure or maintenance greater than 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> CT

• Improve long-term offsite power reliability 3

ModificationBackground- OffsitePowerSources 345kVSwitchyard Protected

Area 2ST U2 Mains T

R Turbine

Generator A

N MOAS Unit2 S

M XST2 Unit1 I

S 1ST Turbine XST2A Generator S

I U1 Mains O

N XST1 S

Y S

T PlantFacilities XST1A E

M Protected

Area PlantFacilities 138kVSwitchyard 4

Disconnect Switch XST1A Disconnect Switch XST1 XFMR XST1 XFMR XST1A Separation/Fire Wall 5

Modification Background Addition of alternate offsite power transformers to enhance reliability for safety related components 1/31/11 - first phase (XST2A) completed Second phase (XST1A) included allowance for two separate 14-day CTs for TS 3.8.1 (72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> to 14 days) 10/22/13 - first 14-day CT completed - 138kV bus work completed 12/4/13 - during second 14-day CT, an energized XST2 6.9kV cable was inadvertently cut 6

Cut Cable Event - Plant Response Loss of the safeguards busses for both Unit 1 and Unit 2 (power to XST2 was interrupted; XST1 been taken out of service to support this work)

Safeguards busses powered from the 4 Emergency Diesel Generators Entered a 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> shutdown action statement on both Unit 1 and Unit 2 per Technical Specifications Both Units remained on line and at power Emergency Plan Unusual Event declared Notice of Enforcement Discretion granted by the NRC to go beyond the 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> to allow for transformer restoration XST2 restored in approximately 27 1/2 hours; XST1 restored 7 hours8.101852e-5 days <br />0.00194 hours <br />1.157407e-5 weeks <br />2.6635e-6 months <br /> later Operator and Equipment performance was excellent 7

Cut Cable Event - Causes Direct Causes

• Responsible engineers overconfidence & over-reliance on craft supervisor input

• Craft failed to stop when unsure Root Cause - Management Team oversight of adherence to standards less than adequate Contributing Causes

• Inadequate design and design review

• Locations identified in XST1/XST1A Final Design Authorization (FDA) were not field verified in the design development and approval process

• Procedure content less than adequate

• Additional verifications and supervisory approval requirements implemented due to a previous cable cutting event were not implemented effectively.

8

Cut Cable Event - Corrective Actions Establish a multi-organizational tracking method to monitor station compliance with station standards and worker/supervisor behaviors Senior management oversight of modification performance provided in the station Management Review Meeting In-field identification of all transformer to 6.9kV cables to provide unique cable and tray identification Procedures require Positive Component Verification for items not uniquely identified New station HU tool on Positive Component Verification Third Party review of selected modifications, including the XST1A modification New procedure on work order planning for modifications Procedure revision to identify limitations of test equipment on shielded cables Perform modification craft and engineering supervision behavior based oral boards 9

Modification Completion Plan Correct design and implementation documents Install transfer panels (boxes), cut and terminate cables for XST1 /

XST1A circuits XST1 and XST1A must be de-energized to perform the installation 10

Proposed Plant Modification Overview New Tap Box Transfer New Transfer Panel Transfer Panel Panels

Risk Management CPNPP Configuration Risk Management Program (CRMP)

• Incorporates the characteristics of the model CRMP described in RG 1.177

• CRMP description incorporated into TS

• Previously approved one-time, 14-day change to TS (XST2A Startup Transformer installation)

• Previously approved for two, one-time 14-day changes to TS (XST1A Startup Transformer installation)

CRMP is requirement of the Maintenance Rule Program. CPNPP endorses guidance in NUMARC 93-01, Industry Guideline For Monitoring the Effectiveness Of Maintenance At Nuclear Power Plants 12

Risk Management (cont.)

[Implemented during the extended CT]

Risk Mitigation Actions (examples)

• Restricted Access to and Suspension of Maintenance in the Switchyard

• Testing of Emergency Diesel Generators (EDGs) and Alternate Power Diesel Generators (APDGs) and Turbine Driven Auxiliary Feedwater Pumps (TDAFWPs) within the Two (2) Weeks Prior to the Start of the XST1 14-day CT

• Rescheduling of Testing and Maintenance on the EDGs, APDGs, TDAFWPs, XST2, Component Cooling Water Pumps (CCWPs) and Station Service Water Pumps (SSWPs) to occur outside the 14-day CT window

• Suspension of Hot Work Activities near XST2 Power and Control Cabling

• Roving Hourly Fire Watch Along Paths of XST2 Power and Control Cabling

• Operations preparations and grid monitoring during the 14-day CT

• Selection of Time of Year Due to Weather Considerations 13

Risk Management (cont.)

[Implemented during the extended CT]

• Risk Mitigation Actions (examples, cont.)

• As a defense-in-depth feature for XST2 and XST1 modifications, APDGs were installed for each Unit. APDGs maintain the capability to provide power for one train of engineered safety feature (ESF) equipment needed for safe shutdown and long term cooling of each Unit during the extended CT to respond to a beyond design basis event if loss of XST2 occurs and both EDGs of a Unit fail to start 14

Risk Management - Severe Weather Considerations

~End of March

~Beginning of October 15

License Amendment Request By July 15, 2014, Luminant plans to submit a LAR request for a one-time, 14 day, offsite power Technical Specification (TS) Completion Time (CT)

Luminant requests that the License Amendment be issued by January 15, 2015 Luminant believes this time frame is achievable based on:

• TS change similar to previously approved requests (ML102810130

& ML13232A143)

• Factors such as duration, work scope and risk management strategies, similar to those previously reviewed

• Previously approved request was for two 14-day CTs whereas this request is for one 14-day CT

• LAR submittal will reflect previous RAI questions and issued Safety Evaluation

• Additional risk management strategies based on lessons learned from events 16

ProposedTechnicalSpecification3.8.1 17

Closing Remarks 18