ML16092A044

Summary of 3/3/2016 Public Meeting with STP Nuclear Operating Company Regarding Open Items, Risk-Informed Generic Safety Issue (GSI) 191 Application and Supplements for South Texas Project, Units 1 and 2 (CAC Nos. MF2400-MF2409)

ML16092A044
Person / Time
Site:	South Texas
Issue date:	04/11/2016
From:	Lisa Regner Plant Licensing Branch IV
To:	South Texas
Regner L
References
CAC MF2400, CAC MF2401, CAC MF2402, CAC MF2403, CAC MF2404, CAC MF2405, CAC MF2406, CAC MF2407, CAC MF2408, CAC MF2409
Download: ML16092A044 (5)

Text

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 April 11, 201 6 LICENSEE: STP Nuclear Operating Company FACILITY: South Texas Project, Units 1 and 2

SUMMARY

OF MARCH 3, 2016, PUBLIC MEETING WITH STP NUCLEAR OPERATING COMPANY TO DISCUSS THE LICENSE AMENDMENT AND EXEMPTION REQUESTS TO USE A RISK-INFORMED APPROACH TO THE RESOLUTION OF GENERIC SAFETY ISSUE 191, "ASSESSMENT OF DEBRIS ACCUMULATION ON PWR SUMP PERFORMANCE" (CAC NOS. MF2400, MF2401, MF2402, MF2403, MF2404, MF2405, MF2406, MF2407, MF2408, AND MF2409)

On March 3, 2016, a Category 1 public meeting was held between the U.S. Nuclear Regulatory Commission (NRG) and representatives of STP Nuclear Operating Company (STPNOC, the licensee), at NRG Headquarters, Rockville, Maryland. The meeting notice and agenda, dated February 18, 2016, are located in the Agencywide Documents Access and Management System (ADAMS) at Accession No. ML16050A006. A list of meeting attendees is provided in the Enclosure to this meeting summary.

By letter dated June 19, 2013 (ADAMS Accession No. ML131750250), as supplemented by letters dated October 3, October 31, November 13, November 21 and December 23, 2013 (two letters); and January 9, February 13, February 27, March 17, March 18, May 15 (two letters),

May 22, June 25, July 15, 2014; and March 10, March 25, and August 20, 2015 (ADAMS Accession Nos. ML13295A222, ML13323A673, ML13323A128, ML13338A165, ML14015A312, ML14015A311, ML14029A533, ML14052A110, ML14072A075, ML14086A383, ML14087A126, ML14149A353, ML14149A354, ML14149A439, ML14178A467, ML14202A045, ML15072A092, ML15091A440, and ML15246A125, respectively), STPNOC submitted exemption requests accompanied by license amendment requests for a risk-informed approach to resolve Generic Safety Issue (GSl)-191, "Assessment of Debris Accumulation on PWR [Pressurized-Water Reactor] Sump Performance, at South Texas Project, Units 1 and 2 (STP).

The purpose of this public teleconference call was to discuss the NRG staff's remaining unresolved concerns associated with the licensee's August 20, 2015, document. This submittal provided information on STPNOC's revised methodology to resolve GSl-191 using a risk combined with a deterministic - 'Risk over Deterministic' or 'RoverD' - methodology. In particular, the staff discussed the outcomes of the thermal-hydraulic (T-H) and debris generation regulatory audits conducted in College Station, Texas, and Albequerque, New Mexico, respectively, during the week of February 22, 2016. Additionally, the NRG and STP staffs discussed the containment analysis impact due to Westinghouse Electric Company LLC (Westinghouse) errors, STPNOC's draft RAI [Request for Additional Information] Applicability Matrix, and the regulatory audit associated with probabilistic risk planned for April 2016.

The NRG staff discussed an option that STPNOC may exercise concerning shifting all hot-leg loop, large-break loss-of-coolant accident (LOCA) locations to a risk-informed methodology to simplify the analysis. The licensee noted that if this option were to be used, it would mean four additional locations on the hot-leg loop vessel nozzles would be moved from a deterministic analysis, to a risk-informed analysis. If the licensee exercised this option, only the hot-leg medium break, hot-leg small break, and cold-leg small break locations would need to demonstrate deterministic compliance per paragraph 50.46(b)(5) of Title 1O of the Code of Federal Regulations. Further, the licensee discussed a T-H modeling assumption change involving allowing the core bypass to be open to allow flow in the axial direction during the long-term core cooling analysis. The assumption of allowing bypass flow was addressed in a Westinghouse guidance document, WCAP-17788, "Comprehensive Analysis and Test Program for GSl-191 Closure (PA-SEE-1090) - Cold Leg Break (CLB) Evaluation Method for GSl-191 Long-Term Cooling," which the NRG staff is currently reviewing.

The NRG staff requested that the licensee provide a clarification in its next submittal concerning steam line break assumptions in the risk analysis model. The August 20, 2015, submittal did not address the secondary system break assumptions, yet the submittal was stated to be a "stand-alone reference." Earlier STP submittals clearly stated the assumptions used in the analysis. This request was provided in a draft RAI by e-mail on March 22, 2016 (ADAMS Accession No. ML16082A484).

The NRG and STPNOC staffs discussed the licensee's draft RAI Applicability Matrix (ADAMS Accession No. ML 16091 AOOS). The NRG staff stated that there are questions on the scope of the review due to the methodology change from the original submittals in 2013. The RAI Applicability Matrix does not address this. The NRG staff stated that the licensee needs to provide assurance that the later submittal(s) do not disagree with earlier information, if it is not made clear that information is superseded.

The next public meetings will be held on March 17 and 31, 2016.

There were no public comments and no meeting feetback forms submitted.

If you have any questions, please contact me at 301-415-1906 or via e-mail at Lisa.Regner@nrc.gov.

Sincerely, rnw~ ~r Lisa M. Regner, Senior Project Manager Plant Licensing Branch IV-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-498 and 50-499

Enclosure:

List of Attendees cc w/encl: Distribution via Listserv

LIST OF ATTENDEES MARCH 3, 2016, CONFERENCE CALL WITH STP NUCLEAR OPERATING COMPANY REGARDING RISK-INFORMED APPROACH TO RESOLUTION OF GSl-191 SOUTH TEXAS PROJECT. UNITS 1 AND 2 DOCKET NOS. 50-498 AND 50-499 NAME ORGANIZATION Lisa Regner U.S. Nuclear Regulatory Commission (NRC)

Vic Cusumano NRC Robert Pascarelli NRC Josh Kaizer NRC Reed Anzalone NRC Steve Laur NRC Andrea Russell NRC Jeremy Dean NRC C. J. Fong NRC Matt Yoder NRC Caroline Tilton NRC Rob Engen STP Nuclear Operating Company (STPNOC)

Ernie Kee STPNOC Wayne Harrison STPNOC Steve Blossom STPNOC Wes Schulz STPNOC Drew Richards STPNOC Bruce Letellier Alion Science & Technology Megan Stachowiak Alien Science & Technology Dominic Munoz Alien Science & Technology Rodolfo Vaghetto Texas A&M Ron Holloway Wolf Creek Nuclear Operating Company Brian Krystek Engineering Planning and Management, Inc.

Tim Sande ENERCON Enclosure

If you have any questions, please contact me at 301-415-1906 or via e-mail at Lisa. Regner@nrc.gov.

Sincerely, IRA MWatford for/

Lisa M. Regner, Senior Project Manager Plant Licensing Branch IV-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-498 and 50-499

Enclosure:

List of Attendees cc w/encl: Distribution via Listserv DISTRIBUTION:

PUBLIC ARussell, NRR/DSS/SSIB LPL4-1 r/f SSmith, NRR/DSS/SSIB RidsACRS_MailCTR Resource PKlein, NRR/DE/ESGB RidsNrrDeEpnb Resource MYoder, NRR/DE/ESGB RidsNrrDeEsgb Resource VCusumano, NRR/DSS/SSIB RidsNrrDorllpl4-1 Resource AGuzzetta, NRR/DSS/SRXB RidsNrrDraApla Resource JDozier, NRR/DRA/ARCB RidsNrrDssScvb Resource CFong, NRR/DRA/APLA RidsNrrDssSnpb Resource Slaur, NRR/DRA/APLA RidsNrrDssSrxb Resource MBanks, ACRS RidsNrrDssSsib Resource KWest, NRR/DSS/STSB RidsNrrDssStsb Resource CTilton, NRR/DSS/STSB RidsNrrLAJBurkhardt Resource ASallman, NRR/DSS/SCVB RidsNrrPMSouthTexas Resource JTsao, NRR/DE/EPNB RidsRgn4MailCenter Resource LWard, NRR/DSS/SNPB TClark, EDO RIV MColon, NRR/DE/ESGB TWertz, NRR LRobinson, NRR/DSS/SSIB ADAMS A ccess1on No. ML16092A044

• per ema1 OFFICE NRR/DORL/LPL4-1 /PM NRR/DORL/LPL4-1/LA NRR/DRA/APLAITL NRR/DSS/SSIB/BC NAME (MWatford for) LRegner JBurkhardt CJ Fong VCusumano DATE 4/11/2016 3/31/2016 4/05/2016 4/05/2016 OFFICE NRR/DSS/SNPB/BC NRR/DORL/LPL4-1 /BC NRR/DORL/LPL4-1/PM NAME JDean RPascarelli (MWatford for) LRegner DATE 4/06/2016 4/08/2016 4/11/2016 OFFICIAL RECORD COPY