ML18192B091
| ML18192B091 | |
| Person / Time | |
|---|---|
| Site: | Vogtle  |
| Issue date: | 07/12/2018 |
| From: | Paul Kallan NRC/NRO/DLSE/LB4 |
| To: | Jennifer Dixon-Herrity NRC/NRO/DLSE/LB4 |
| KALLAN P/415-2809 | |
| References | |
| LAR 17-031 | |
| Download: ML18192B091 (10) | |
Text
July 12, 2018 MEMORANDUM TO:
Jennifer Dixon-Herrity, Chief Licensing Branch 4 Division of Licensing, Siting, and Environmental Analysis, Office of New Reactors FROM:
Paul Kallan, Senior Project Manager
/RA/
Licensing Branch 4 Division of Licensing, Siting, and Environmental Analysis, Office of New Reactors
SUBJECT:
AUDIT PLAN FOR VOGTLE ELECTRIC GENERATING PLANT UNITS 3 AND 4, REQUEST FOR LICENSE AMENDMENT:
EFFECT OF ROD SHADOWING ON EXCORE POWER RANGE DETECTORS, CHANGES TO NUCLEAR OVERPOWER REACTOR TRIPS, AND CHANGES TO MONITORING OF MODERATOR TEMPERATURE COEFFICIENT AND CORE POWER DISTRIBUTION (LAR 17-031)
By letter dated September 8, 2017 (Agencywide Documents Access and Management System (ADAMS) Accession Number ML17251A458), Southern Nuclear Operating Company (the licensee) requested an amendment to Combined License Numbers NPF-91 and NPF-92, for Vogtle Electric Generating Plant (VEGP) Units 3 and 4.
The requested amendment requires changes to the Updated Final Safety Analysis Report in the form of departures from the Plant-Specific Design Control Document Tier 2 information and involves changes to the VEGP Units 3 and 4 COL Appendix A, Technical Specifications (TS).
The requested amendment proposes to revise the licensing basis information for the design of the protection and safety monitoring system (PMS) automatic reactor trips and the crediting of PMS automatic reactor trips necessary to prevent exceeding fuel design limits including the power range high neutron flux (high setpoint), the power range high positive flux rate trip, the overpower T trip, and the overtemperature T trip. Also, changes to the COL Appendix A TS for maintaining moderator temperature coefficient and maintaining power distributions within the required absolute power generation limits.
CONTACT:
Paul Kallan, NRO/DLSE/LB4 301-415-2809
J. Dixon-Herrity The Reactor Systems, Nuclear Performance & Code Review Branch staff plans to conduct an audit to gain better understanding of proposed changes to reach reasonable assurance findings and review related documentation and non-docketed information to evaluate conformance with the Standard Review Plan or technical guidance.
Docket Nos.: 52-025 and 52-026
Enclosure:
Regulatory Audit Plan cc: See next page
ML18192B091 NRO-002 OFFICE DLSE/LB4/PM DLSE/LB4/LA DLSE/LB4/BC NAME PKallan RButler JDixon-Herrity DATE 7/12/18 7/11/18 7/12/18
Vogtle Units 3 & 4 Mailing List (Revised 03/13/2018) cc:
Office of the Attorney General Resident Inspector 40 Capitol Square, SW Vogtle Plant Units 3 & 4 Atlanta, GA 30334 8805 River Road Waynesboro, GA 30830 Resident Manager Oglethorpe Power Corporation Mr. Barty Simonton Alvin W. Vogtle Nuclear Plant Team Leader 7821 River Road Environmental Radiation Program Waynesboro, GA 30830 Air Protection Branch Environmental Protection Division Southern Nuclear Operating Company 4244 International Parkway, Suite 120 Document Control Coordinator Atlanta, GA 30354-3906 42 Inverness Center Parkway, Bin 237 Birmingham, AL 35242 George B. Taylor, Jr.
2100 East Exchange Pl Anne F. Appleby Atlanta, GA 30084-5336 Olgethorpe Power Corporation 2100 East Exchange Place Brian H. Whitley Tucker, GA 30084 Regulatory Affairs Director Southern Nuclear Operating Company County Commissioner 42 Inverness Center Parkway, BIN B237 Office of the County Commissioner Birmingham, AL 35242 Burke County Commission Waynesboro, GA 30830 Mr. Michael Yox Site Regulatory Affairs Director Mr. Wayne Guilfoyle Vogtle Units 3 & 4 Commissioner District 8 7825 River Road, Bin 63031 Augusta-Richmond County Commission Waynesboro, GA 30830 4940 Windsor Spring Rd Hephzibah, GA 30815 Gwendolyn Jackson Burke County Library 130 Highway 24 South Waynesboro, GA 30830 Mr. Reece McAlister Executive Secretary Georgia Public Service Commission Atlanta, GA 30334 Page 1 of 3
Vogtle Units 3 & 4 Mailing List Email acchambe@southernco.com (Amy Chamberlian) agaughtm@southernco.com (Amy Aughtman)
ALPUGH@southernco.com (Amanda Pugh) awc@nei.org (Anne W. Cottingham) becky@georgiawand.org (Becky Rafter) bhwhitley@southernco.com (Brian Whitley)
Bill.Jacobs@gdsassociates.com (Bill Jacobs) bjadams@southernco.com (Brad Adams) bwwaites@southernco.com (Brandon Waites) castelca@westinghouse.com (Curtis Castell) comerj@westinghouse.com (James Comer) crpierce@southernco.com (C.R. Pierce) dahjones@southernco.com (David Jones) david.hinds@ge.com (David Hinds) david.lewis@pillsburylaw.com (David Lewis) dgbost@southernco.com (Danny Bost) dlfulton@southernco.com (Dale Fulton) drculver@southernco.com (Randy Culver) durhamdc@westinghouse.com (David Durham) ed.burns@earthlink.net (Ed Burns) edavis@pegasusgroup.us (Ed David) erg-xl@cox.net (Eddie R. Grant) fdhundle@southernco.com (Forrest Hundley) fhwillis@southernco.com (Fred Willis)
G2NDRMDC@southernco.com (SNC Document Control) graysw@westinghouse.com (Scott W. Gray) jadwilli@southernco.com (J.D. Williams) james1.beard@ge.com (James Beard) jannina.blanco@pillsburylaw.com (Jannina Blanco) jantol1dj@westinghouse.com (David Jantosik) jenmorri@southernco.com (Jennifer Buettner)
JHaswell@southernco.com (Jeremiah Haswell) jim@ncwarn.org (Jim Warren)
John.Bozga@nrc.gov (John Bozga)
Joseph_Hegner@dom.com (Joseph Hegner) jpredd@southernco.com (Jason R. Redd) jranalli@meagpower.org (Jerry Ranalli) karen.patterson@ttnus.com (Karen Patterson) karlg@att.net (Karl Gross) kmstacy@southernco.com (Kara Stacy)
KSutton@morganlewis.com (Kathryn M. Sutton)
Page 2 of 3
Vogtle Units 3 & 4 Mailing List kwaugh@impact-net.org (Kenneth O. Waugh) lchandler@morganlewis.com (Lawrence J. Chandler)
Marc.Pickering@hq.doe.gov (Marc Pickering) markus.popa@hq.doe.gov (Markus Popa) mdmeier@southernco.com (Mike Meier) media@nei.org (Scott Peterson)
Melissa.Smith@Hq.Doe.Gov (Melissa Smith)
Michael.Kuca@hq.doe.gov (Michael Kuca) mike.price@opc.com (M.W. Price)
MKWASHIN@southernco.com (MKWashington) mlgraves@southernco.com (Michelle Graves)
MSF@nei.org (Marvin Fertel) myox@southernco.com (Mike Yox) nirsnet@nirs.org (Michael Mariotte)
Nuclaw@mindspring.com (Robert Temple) patriciaL.campbell@ge.com (Patricia L. Campbell)
Paul@beyondnuclear.org (Paul Gunter) pbessette@morganlewis.com (Paul Bessette) r.joshi15@comcast.net (Ravi Joshi)
RJB@NEI.org (Russell Bell)
Ronald.Jones@scana.com (Ronald Jones) rwink@ameren.com (Roger Wink) sabinski@suddenlink.net (Steve A. Bennett) sara@cleanenergy.org (Sara Barczak) sblanton@balch.com (Stanford Blanton)
Shiva.Granmayeh@hq.doe.gov (Shiva Granmayeh) sjackson@meagpower.org (Steven Jackson) skauffman@mpr.com (Storm Kauffman) sroetger@psc.state.ga.us (Steve Roetger) stephan.moen@ge.com (Stephan Moen) stephen.burdick@morganlewis.com (Stephen Burdick) tom.miller@hq.doe.gov (Tom Miller)
TomClements329@cs.com (Tom Clements)
Vanessa.quinn@dhs.gov (Vanessa Quinn) vcsummer2n3@gmail.com (Brian McIntyre) wasparkm@southernco.com (Wesley A. Sparkman) wayne.marquino@gmail.com (Wayne Marquino) weave1dw@westinghouse.com (Doug Weaver) x2gabeck@southernco.com (Gary Becker) x2kmseib@southernco.com (Kristin Seibert)
Page 3 of 3
AUDIT OF REPORTS AND CALCULATIONS IN SUPPORT OF REQUEST FOR LICENSE AMENDMENT RELATED TO THE EFFECT OF ROD SHADOWING ON EXCORE POWER RANGE DETECTORS, CHANGES TO NUCLEAR OVERPOWER REACTOR TRIPS, AND CHANGES TO MONITORING OF MODERATOR TEMPERATURE COEFFICIENT AND CORE POWER DISTRIBUTION SOUTHERN NUCLEAR OPERATING COMPANY VOGTLE ELECTRIC GENERATING PLANT, UNITS 3 AND 4 Docket Nos.52-025 and 52-026 A.
Background
By letter dated September 8, 2018 (Reference 1), Southern Nuclear Operating Company (SNC/licensee) submitted License Amendment Request (LAR)17-031 requesting that the U.S. Nuclear Regulatory Commission (NRC or Commission) amend the combined licenses (COL) for Vogtle Electric Generating Plant (VEGP) Units 3 and 4, COL Numbers NPF-91 and NPF-92, respectively.
The requested amendment (LAR 17-031) would revise the Updated Final Safety Analysis Report (UFSAR) in the form of departures from the incorporated plant-specific Design Control Document Tier 2 information, with corresponding changes to the associated COL Appendix A, Technical Specifications. Specifically, the requested amendment proposes changes to (1) the design of the Protection and Safety Monitoring (PMS) system, (2) the crediting of trips in Chapter 15 transient and accident analyses, and (3) additional changes to technical specifications for the moderator temperature coefficient, power distributions, and the On-Line Power Distribution Monitoring System. The proposed changes to the PMS system and the crediting of trips in the Chapter 15 transient and accident analyses address issues caused by increased uncertainties in the ex-core nuclear instrumentation during mechanical shim (MSHIM) operations.
The purpose of this audit is to gain a better understanding of the uncertainties introduced by MSHIM operation and the proposed approach for addressing these uncertainties. Several questions for which NRC staff is seeking clarity are provided in Attachment 1 to this audit plan.
B.
Regulatory Audit Basis This regulatory audit is based on the following:
LAR-17-031, Enclosure 1, Section 2.1, Section 2.2, and Section 2.3 (Reference 1)
VEGP Units 3 and 4, UFSAR, Section 15.4.2, and Section 15.4.8 (Reference 2)
COL, Appendix A, VEGP Units 3 and 4, Technical Specificiations (Reference 3 and Reference 4)
2 C
Regulatory Audit Scope or Methodology The audit team will view the calculations that provide the technical support for LAR-17-031. In addition, the audit team will meet with subject matter expert(s) to discuss (1) the nature and magnitude of the increased uncertainties associated with MSHIM operation, (2) the specific issues caused by the increased uncertainties, and (3) the proposed approach to address the increased uncertainties.
D.
Information and Other Material Necessary for the Regulatory Audit The following documents are to be made available to the NRC staff either at a local office or in the electronic reading room:
- 1. The calculation note(s) used to develop the updated f(I) penalty functions for the Overtemperature T and Overpressure T trips.
- 2. The calculation note(s) used to determine the uncertainty in trip setpoints for Power Range Neutron Flux High, Power Range Neutron Flux Low, Power Range Neutron Flux High Positive Rate, Overtemperature T, and Overpower T.
- 3. The calculation notes that support UFSAR Section 15.4.2, Uncontrolled Rod Cluster Control Assembly Bank Withdrawal at Power, and UFSAR Section 15.4.8, Spectrum of Rod Cluster Control Assembly Ejection Accidents.
Other documents may be requested based on the staffs review of the above documents.
Appropriate handling and protection of proprietary information shall be acknowledged and observed throughout the audit.
E.
Audit Team The following are the NRC audit team members:
Paul Kallan, Senior Project Manager (NRC), Lead Timothy Drzewiecki, Reactor Systems Engineer (NRC), Technical Reviewer Antonio Barrett, Reactor Systems Engineer (NRC), Technical Reviewer F.
Logistics Date: July 2018 Location:
Westinghouse Electric Company, LLC Washington Operations 11333 Woodglen Drive, Suite 203 Rockville, MD 20852 Telephone: 301-881-7040/7042 Additionally, the review of documents supporting LAR-17-031, and identified in Section D of this audit plan, can be conducted from either NRC Headquarters via the licensees electronic reading room.
3 Location:
NRC Headquarters Two White Flint North 11545 Rockville Pike Rockville, MD 20852-2738 G.
Special Requests NRC staff requests that subject matter expert(s) be made available to discuss the (1) the nature and magnitude of the increased uncertainties associated with MSHIM operation, (2) the specific issues caused by the increased uncertainties, and (3) the proposed approach to address the increased uncertainties. In particular, NRC staff will be seeking clarification to the questions identified in Attachment 1 to this audit plan.
If necessary, any circumstances related to the performance of the audit will be communicated to Paul Kallan (NRC) at 301-415-2809 or Paul.Kallan@nrc.gov.
H.
Deliverables At the completion of the audit, the NRC staff will prepare an audit report within 45 days that will be declared and entered as an official agency record in the NRCs Agencywide Documents Access and Management System (ADAMS). The audit outcome may be used to identify any additional information to be submitted for making regulatory decisions, and will assist the NRC staff in the issuance of Requests for Additional Information (if necessary) in completing its review of LAR 031. With the anticipated exit telecom in July 2018, the audit report will be completed by August 2018.
I.
References
- 1. Southern Nuclear Operating Company, Vogtle Electric Generating Plant Units 3 and 4 Request for License Amendment: Effect of Rod Shadowing on Excore Power Range Detectors, Changes to Nuclear Overpower Reactor Trips, and Changes to Monitoring of Moderator Temperature Coefficient and Core Power (LAR 17-031), September 8, 2017 (ADAMS Accession No. ML17251A458).
- 2. Vogtle Electric Generating Plant Units 3 and 4, Updated Final Safety Analysis Report, Revision 6 and Tier 1, Revision 5, June 15, 2017 (ADAMS Accession No. ML17172A218).
- 3. Combined License NPF-91 for Vogtle Electric Generating Plant Unit 3, Southern Nuclear Operating Company (ADAMS Accession No. ML14100A106).
- 4. Combined License NPF-92 for Vogtle Electric Generating Plant Unit 4, Southern Nuclear Operating Company (ADAMS Accession No. ML14100A135).
Attachment Audit Questions
- 1. Axial Flux Difference Penalties
- a. How do the updated f(I) penalties compare to the old penalites?
- b. How are the updated f(I) penalties generated?
- c. How is weighted peripheral axial sufficient to represent the axial power shape in the limiting rod (i.e., explain how the modeling of the Overtemperature T and Overpower T in the safety analyses is conservative)?
- 2. Setpoint Uncertainty
- a. What is the magnitude of the increased uncertainties associated with mechanical shim (MSHIM) operation?
- b. Clarify how the proposed changes to Technical Specifications resolve the issues associated with the increased uncertainty associated with MSHIM operation.
- c. Clarify how the proposed changes to the Overpower limit and Overpower T trip setpoint resolve the harsh environment issue.
- a. Explain why the Overpower T trip provides the same level of protection as the Power Range Neutron Flux trip.