ML12188A697

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6/26/12 Summary of Meeting with Luminant Generation Company LLC to Discuss Proposed License Amendment Request to Revise TS 3.8.1, AC Sources - Operating, to Support Installation of Backup Transformer at Comanche Peak, Units 1 and 2 (TAC ME8
ML12188A697
Person / Time
Site: Comanche Peak  Luminant icon.png
Issue date: 07/18/2012
From: Balwant Singal
Plant Licensing Branch IV
To:
Singal B
References
TAC ME8615, TAC ME8616
Download: ML12188A697 (35)


Text

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 July 18, 2012 LICENSEE: Luminant Generation Company LLC FACILITY: Comanche Peak Nuclear Power Plant, Units 1 and 2

SUBJECT:

SUMMARY

OF JUNE 26, 2012, PRE-LICENSING PUBLIC MEETING WITH LUMINANT GENERATION COMPANY LLC TO DISCUSS THE PROPOSED LICENSE AMENDMENT REQUEST IN SUPPORT OF A PLANT MODIFICATION TO INSTALL A BACKUP TRANSFORMER FOR OFFSITE AC POWER SOURCE (TAC NOS. ME8615 AND ME8616)

On June 26, 2012, a public meeting was held between the U.S. Nuclear Regulatory Commission (NRC), and representatives of Luminant Generation Company LLC (Luminant, the licensee), at NRC Headquarters, Rockville, Maryland. The meeting notice and agenda, dated June 11,2012, is located in the Agencywide Documents Access and Management System (ADAMS) under Accession No. ML12171A184. The purpose of the meeting was to discuss the proposed license amendment request by the licensee for extended completion time for Technical Specification (TS) 3.8.1, HAC [Alternating Current] Sources - Operating," in support of a plant modification to install a backup transformer for offsite power sources at Comanche Peak Nuclear Power Plant (CPNPP), Units 1 and 2.

A list of meeting attendees is provided in Enclosure 1 to this meeting summary.

Meeting Summary The discussion was based on the following meeting materials/handouts:

The licensee provided a revised copy of the handout on the day of the meeting and a copy of the revised handout is provided in Enclosure 2 to this meeting summary.

Results of Discussions

1. The NRC staff requested several clarifications in the area of probabilistic risk assessment (PRA) concerning the proposed extended completion time for Limiting Condition for Operation (LCO) 3.8.1, Required Action A.3. The results of the discussions are described below:
a. Internal Events and Internal Flooding In response to the NRC staff question about timing of the peer review per NRC Regulatory GUide (RG) 1.200, Revision 2, HAn Approach for Determining the Technical Adequacy of Probabilistic Risk Assessment Results for Risk-Informed

-2 Activities," March 2009 (ADAMS Accession No. ML090410014), the licensee confirmed that it performed a peer review in early 2011. This peer review was performed after the previous application dated October 26, 2009, for installation of a backup transformer to XST2. The licensee agreed to document the Peer Review Facts and Observations (F&Os), the plant disposition, and the achieved capability category in its formal submittal.

b. Internal Fire The licensee agreed to provide an assessment which demonstrates the significance of an internal fire with respect to the acceptance guidelines of RG 1.174, Revision 2, "An Approach for Using Probabilistic Risk Assessment in Risk-Informed Decisions on Plant-Specific Changes to the Licensing Basis," May 2011 (ADAMS Accession No. ML100910006), and RG 1.177, Revision 1, "An Approach for Plant-Specific, Risk-Informed Decisionmaking: Technical Specifications," May 2011 (ADAMS Accession No. ML100910008). The licensee, however, indicated that this assessment would be qualitative, supported by quantitative assessments and considerations. Insights would be derived from this assessment. The NRC staff recommended that Section 1.2.4, "Internal Fire Technical Elements," of RG 1.200 be discussed, in order to put the CPNPP, Units 1 and 2 fire insights and basis into perspective. The NRC staff suggested that the discussion related to Section 1.2.4 of RG 1.200 address the CPNPP baseline fire analysis and the fire analysis incorporating the extended completion time.
c. Other Hazards Should a qualitative argument for other hazards (e.g., seismic, high winds, external floods) be important with respect to RGs 1.174 and 1.177 guidelines, the licensee should address the corresponding section in RG 1.200, Revision 2, on technical characteristics and attributes to place their insights into perspective.

For example, such discussion may be needed for high winds, which corresponds to Section 1.2.7 of RG 1.200.

Consistent with RG 1.174, all hazards should be addressed in the submittal.

2. The NRC staff emphasized that to conclude the PRA assessment of hazards meets the guidelines provided by RGs 1.174 and 1.177, the assessment of hazards beyond internal events/flooding, needs to be rigorous.
3. The NRC staff indicated that the licensee's Individual Plant Examination External Events (IPEEE) assessment or any other previous assessment mayor may not have fully addressed the failure modes incorporated into the American Society of Mechanical Engineers/American Nuclear Society (ASME/ANS) PRA Standard, RA-Sa-2009.

However, the NRC staff expects the licensee to incorporate all failure modes in its assessments and insights for the proposed submittal. For example for fire, hot shorts.

and high-energy arcing faults should be assessed for their impact on the extended completion time.

-3

4. The licensee indicated that fixed ignition sources are important to the fire insights. As a result, the NRC staff suggested that additional compensatory measures, such as infrared thermography, may be considered on the fixed ignition sources prior to entering the extended completion time. The licensee agreed to evaluate this option.
5. Based on the discussions during the meeting, the NRC staff understands that the licensee plans to implement the proposed plant modifications with both units operating at power. The NRC staff felt that a request to extend the completion time for T5 3.8.1 from 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> to 14 days (twice) (a total of 28 days) is unprecedented. The NRC staff believed that the proposed amendment request will need to provide a strong safety justification, with sufficient detail, to establish a position that the proposed offsite power system modifications can be conducted safely and without incident. The NRC staff questioned whether the plant will be safer if the proposed plant modifications are performed with at least one unit in refueling outage.
6. The NRC staff also suggested that the licensee discuss the following in the proposed amendment request:
  • Condition of all major components relied upon to serve as the single offsite source during the extended completion time including a discussion of any systems, structures, and components covered by Title 10 of the Code of Federal Regulations (10 CFR), paragraph 50.65(a)(1) relied upon during this period.
  • Historic loss-of-offsite power events at CPNPP, including corrective actions resulting from these events.
  • Contingency plans for potential "what if' scenarios such as adverse weather, transmission system operator warnings or alerts of actual or predicted transmission system capacity or capability issue(s) affecting CPNPP, APDG inoperability occurring after the extended completion time is entered, loss of offsite power, etc.
  • Justification for implementing the proposed plant modifications at power versus with one or both units in a shutdown condition.

No Public Meeting Feedback Forms were received for this meeting.

- 4 Please direct any inquiries to me at (301) 415-3016, or balwant.singal@nrc.gov.

Sincerely, bq\ \0otv.::\ ~~'~

Balwant K. Singai, Senior Project Manager Plant Licensing Branch IV Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-445 and 50-446

Enclosures:

1. List of Attendees
2. Revised Handout cc w/encl: Distribution via Listserv

LIST OF ATTENDEES JUNE 26,2012. MEETING WITH LUMINANT GENERATION COMPANY LLC REGARDING TECHNICAL SPECIFICATION 3.8.1 EXTENSION OF COMPLETION TIME COMANCHE PEAK NUCLEAR POWER PLANT. UNITS 1 AND 2 DOCKET NOS. 50-445 AND 50-446 NAME TITLE ORGANIZATION Matthew Hamm Reactor Systems Engineer U.S. Nuclear Regulatory Commission (NRC)

GerryWaig* Senior Reactor Systems Engineer NRC Khadijah Hemphill General Engineer NRC James Anderson Branch Chief NRC Rui Li Electrical Engineer NRC Roy Matthew Team Leader NRC JS Hyslop Senior Risk and Reliability Engineer NRC Jigar Patel Risk and Reliability Engineer NRC Mike Snodderly Acting Branch Chief NRC Balwant K. Singal Senior Project Manager NRC Michael Markley** Branch Chief NRC Fred Madden Director, Oversight and Regulatory Luminant Generation Company LLC Affairs (Luminant)

Nathan Larson Senior Engineer, PRA Luminant Robert Lichtenstein Project Manager Luminant Tamera J. Ervin- Principal Engineer, Nuclear Luminant Walker

  • Participated via phone
    • Attended the meeting part time Enclosure 1

Modification of Offsite Power Supplies to Improve Reliability at Comanche Peak Nuclear Power Plant June 26, 2012 Enclosure 2

luminant Pre-Application Meeting Agenda

Introductions

Purpose Current Plant Design, TS 3.8.1, and Offsite Power Switchyard Upgrades Proposed Plant Mod, TS 3.8.1, and Offsite Power TS 3.8.1 Extended Completion Time Alternate Power Diesel Generators NUREG-0800 Limited Work Area Risk Analysis Proposed Schedule Closing Remarks

Introductions

Fred Madden Director Oversight & Reg Affairs Jeff Lamarca Project Manager Robert Slough Consult. Licensing Analyst Tamera Ervin-Walker Principal Engineer Nuc.

Nathan Larson Risk & Reliability Engineer Bob Lichtenstein Risk & Reliability Engineer

Purpose The proposed plant modification will facilitate connection of Startup Transformer (ST) XSTl or an alternate ST XST1A to the lE buses within the current Technical Specification (TS) Completion Time (CT) of 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. This is an improvement in plant design which eliminates the necessity to shutdown both Units if XSTl fails or requires maintenance that goes beyond the current Technical Specification (TS) Completion Time (CT) of 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. This change will improve the long-term reliability of the 138kV offsite circuit by providing connection to the ESF buses through XSTl or the new spare startup transformer.

Proposed CPNPP Offsite AC Power Sources r-'-'-'-'-'-'-'-'-'-'-'-'-'-'-

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345kV Switchyard Reliability Upgrades

  • All 345kV breakers have been replaced except for three breakers (8020, 8030, and 8080) which will be replaced this fall.
  • Installation of new bus tie 345kV breaker 8075 to 8080 feeds transformer 25T.
  • Addition of two-345kV lines Everman and Parker 2.
  • Future plans are to replace all the electro mechanical relays with digital relays.

Current AC Distribution to CPNPP 1 E Busses 345 kV Switchyard i 138 kV Switchyard XSu.LXST~ XS~

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Current Technical Specification 3.8.1 CONDfTlON RECUIREDACTIC>N COMPLETION TIME A.. One requlre.d 01IUe croolt IA. 1 Perrorm DR 3.8.1.1 fOr reqUired 1 hOur Incpe I:iIb Ie. OPER.A8LE 01'I'sIte c:m:ufl

~NO once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />.

tIlerea1ter lAND A.2 - - - - - N O T E - - - -

In MODES 1, 2 and 3, me TDAFW pump 1& oon&Idered a f1!quM"ed redlrll:sant feature.

DE!CIa~ reqJ.8"ed fE'atuI'1!(S) 'tIt1II1 no 24 hol.lf5 frOm dl&CCJVery Dn&Ite power 3V3I'IaI:Me II'IOpef'abIe or no Dn&Ite power to when /bi. redlrlilant required Dne train oonCUrren1 1'ea'tllre(&) IS IllOpI!'I'atlfe. wt1tIlnc:tpI!I'3b1tty.

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lAND A.3 RI!'&1l::ft required oIT&Ite arcut 1D 72hol.lf5 OPERABLE SlaM.

f!l 14 days 'RlI' .iii one-:Hme DLI'I3ge on XST2 to completE! 3 plant mDdl1'llca1l0n 10 De completed by M2d11.2D11.

Current CPNPP Offsite AC Power Sources r-'-'

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Proposed Plant Modification Overview 345 kV Switchyard i 138 Ichyard XS-aLXST~ XST1 XST1A

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Transfer Panel 1EA2-111EA2-2 1 12EA1 -2 1:.BTh.(I L,...BTTI)

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Proposed Technical Specification 3.8.1 c::oNOrr tON I REQUIRE,D ACTtON COMPI.ETtON TIME A. 0rIe- r<<f1Ui'ted df!iIe. cir(:uit

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Proposed CPNPP Offsite AC Power Sources

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Alternate Power Diesel Generators (APDGs)

As a defense-in-depth feature concerning XST2 modification, a set of APDGs were installed for each Unit.

APDGs maintains the capability to provide power for one train of ESF equipment needed for safe shutdown and long term cooling of each Unit during the two extended CT to respond to a beyond design basis event if loss of XST2 occurs and both EDGs of a Unit fail. The installed APDGs are rated higher than the ones described in LAR 09-003 and in CPNPP's response to NRC RAls.

NUREG-0800 The NRC Standard Review Plan NUREG 0800, BTP 8-8, dated Initial - February 2012 states, "An EDG or offsite power AOT license amendment of more than 14 days should not be considered by the staff for review."

Risk Analysis

- Summarize PRA Model Scope and Quality

- Describe the Risk Assessment

- Discuss the Sensitivity Analyses

- Discuss the Configuration Risk Management Program (CRMP)and Risk Reduction Measures

PRA Model Scope and Quality

  • Internal Events and Internal Flooding models were developed per RG 1.200 Rev 2 requirements and have been Peer Reviewed Per the Peer Review Team "Overalt the CPNPP PRA was found to substantially meet the ASME PRA Standard at Capability Category /I and can be used to support risk-informed applications N

PRA Model Scope and Quality

  • Subsequent to the Peer Review, Findings and Observations were addressed and incorporated into the current Revision 4A model

- All "Not Met"... now Cat II or better

- 4 of 7 previous Cat I ... now Cat II or better Remaining 3 with no application impact

- All Findings were resolved and incorporated

- All but one suggestion incorporated One was deferred with no application impact

- All remaining Support Requirements (SR) meet Cat II or better

  • External Events based on IPEEE and will be used for insights

PRA Model Scope and Quality

  • Adequately addresses as-built, as-operated plant
  • Plant specific data and plant specific best estimate Thermal-Hydraulic address success criteria
  • Switchyard and electrical power system modeling is detailed
  • Alternate Power Diesel Generator (APDG) is installed and modeled in the PRA to improve onsite power capabilities
  • RCP Seal LOCA modeling uses the WOG 2000 model for high temperature seals
  • Convolution method used for LOOP recovery analyses

Description of Risk Assessment

  • Applicable Guidance and Criteria
  • Quantitative Analyses for Internal Events and Flood, Levell and II
  • Qualitative Analyses for External Events
  • Qualitative discussion combined with IPEEE risk insights for the Fire, High Winds (Tornado), and Seismic (Margins)
  • Supported by detailed walk-down of plant

Discussion of Sensitivity Analyses

  • Sensitivity studies are used to address uncertainties.

These studies will include but are not limited to:

- Reliability of components important to the risk contributions of the CT extension

- No Credit for the APDG

- LOOP Recovery Probabilities

- Increased duration of XSTl CT

- Conservation of maintenance

  • Uncertainty analysis will be performed per NUREG 1855.

- Common Cause Failure discussion

Configuration Risk Management Program

  • CPNPP has a Configuration Risk Management Program

- Incorporates the characteristics of the model Configuration Risk Management Program described in RG 1.177

- CRMP description has been incorporated into plant Technical Specifications - 5.5.18

- Previously approved for one time 14-day change to Technical Specifications for AC Sources - Operating - B 3.8.1 Required Action A.3 (XST2A transformer installation)

CPNPP endorses the guidance in NUMARC 93-01, "Industry Guideline For Monitoring the Effectiveness Of Maintenance At Nuclear Power Plants"

  • CPNPP will meet the fire (a)(4) requirement by December 1, 2013

Configuration Risk Management Program Risk Mitigation Actions

[Implemented during the extended CTs]

1. Restricted Access to and Suspension of Maintenance in the Switchyard.
2. Testing of Diesel Generators (EDG and APG) and Turbine Driven Auxiliary Feedwater Pumps within the Two (2) Weeks Prior to the Start of the XST1 extended CT.
3. Rescheduling of Testing and Maintenance on the EDGs, APGs, TDAFWPs, XST2, CCWPs and SSWPs to occur outside the extended CT window.
4. Suspension of Hot Work Activities Near XST2 Power and Control Cabling.
5. Roving Hourly Fire Watch Along Paths of XST2 Power and Control Cabling.
6. Operations preparations and grid monitoring during the CT.
7. Selection of Time of Year Due to Weather Considerations.

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Preliminary Conclusions of Risk Assessment

  • The preliminary PRA results show that the extension of the total XSTl CT will have minimal impact on plant risk

Proposed Schedule for LAR Submittal and Staff Review

  • Luminant Power will Submit the LAR by September 2012.
  • Luminant Power requests approval of the proposed License Amendment by September 30, 2013, to be implemented within 120 days of the issuance of the license amendment.

-4 Please direct any inquiries to me at (301) 415-3016, or balwant.singal@nrc.gov.

Sincerely, IRA!

Balwant K. Singai, Senior Project Manager Plant Licensing Branch IV Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-445 and 50-446

Enclosures:

1. List of Attendees
2. Revised Handout cc w/encl: Distribution via Listserv DISTRIBUTION:

PUBLIC TWertz, NRR LPLIV r/f SKennedy, EDO RIV RidsAcrsAcnw_MailCTR Resource JHyslop, NRR/DRAIAPLA RidsNrrDeEeeb Resource MSnodderly, NRR/DRAIAPLA RidsNrrDorlLpl4 Resource JPatel, NRRIDRAIAPLA RidsNrrDraApla Resource RMathew, NRRlDE/EEEB RidsNrrDssStsb Resource MHamm, NRRlDSS/STSB RidsNrrLAJBurkhardt Resource RLi, NRRlDE/EEEB RidsNrrPMComanchePeak Resource KHemphill, NRR/DSS/STSB RidsOgcRp Resource GWaig, NRR/DSS/STSB RidsRgn4MailCenter Resource ADAMS Accession No ML12188A697 "'Via e-mail OFFICE NRR/LPL4/PM NRR/LPL4/LA NRR/DRAlAPLAlBC NRR/DSS/STSB/BC MSnodderly (A)

NAME BSingal JBurkhardt BBeasley for'" RElliott DATE 7/16/12 7/9112 7/16/12 7/16/12 OFFICE NRR/DE/EEEB/BC NRR/LPL4/BC NRR/LPL4/PM MMarkley NAME JAndersen'" JSebrosky for BSingal DATE 7/9/12 7/17/2012 7/18/12 OFFICIAL RECORD COpy