ML16354A121
| ML16354A121 | |
| Person / Time | |
|---|---|
| Site: | Vogtle  |
| Issue date: | 12/27/2016 |
| From: | Marshall M Plant Licensing Branch 1 |
| To: | |
| Marshall, M, NRR/DORL/LPL1 | |
| References | |
| CAC MF8488, CAC MF8489 | |
| Download: ML16354A121 (5) | |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 December 27, 2016 Southern Nuclear Operating Company, Inc.
FACILITY: Vogtle Electric Generating Plant, Units 1 and 2
SUBJECT:
SUMMARY
OF NOVEMBER 29, 2016, PUBLIC MEETING WITH SOUTHERN NUCLEAR OPERATING COMPANY ON PLANNED SUBMITIAL OF VOGTLE ELECTRIC GENERATING PLANT, UNITS 1 AND 2, LICENSE AMENDMENT AND EXEMPTION REQUESTS CONCERNING RESOLUTION OF GENERIC SAFETY ISSUE 191 (CAC NOS. MF8488 AND MF8489)
On November 29, 2016, a Category 1 public meeting was held between the U.S. Nuclear Regulatory Commission (NRC) and representatives of Southern Nuclear Operating Company (SNC or the licensee) at NRC Headquarters, One White Flint North, 11555 Rockville Pike, Rockville, Maryland. The purpose of the meeting was for SNC to provide an overview of its planned risk-informed license amendment request (LAR) involving the resolution of GSl-191, "Assessment of Debris Accumulation on Pressurized Water Reactor (PWR) Sump Performance," for the Vogtle Electric Generating Plant, Units 1 and 2 (VEGP). The meeting notice and agenda, dated November 15, 2016, are available in the Agencywide Documents Access and Management System (ADAMS) at Accession No. ML16320A073. A list of participants is enclosed.
The licensee's presentation slides used at the meeting are available in ADAMS at Accession No. ML16337A298. The licensee described the information that it plans to include in its risk-informed submittal. SNC described the features and plant operations that are relevant to the planned license amendment and exemption requests, which included overall layout of VEGP, strainer arrangement, and plant response. SNC provided an overview of the layout and content of the planned submittal. During its presentation, the licensee addressed the following topics:
- Hybrid loss-of-coolant accident frequency methodology sensitivity
- Credit for containment accident pressure
- Fiber quantity required for chemical head loss
- Partially submerged breaks
- Probabilistic risk assessment model and interface
- Risk quantification
- Sensitivity and uncertainty quantification SNC asked the NRC staff for feedback on the methods it plans to use to address specific technical issues and to identify potential gaps in the submittal. The NRC staff informed the licensee that the following needs to be addressed in its submittal:
- Justification for conservatism in flashing and de-gas calculations.
- Justification for the assumed minimum bed thickness at which chemical head loss may occur.
- Description of all five key principles for risk-informed submittals, including monitoring.
- If planning to seek "credit" for other previously reviewed and approved risk-informed licensing actions, explain the applicability of the disposition of findings and observations to the planned submittal.
- Indication (e.g., tabulated) of weld locations subject to multiple degradation mechanisms or nearing bounding quantity of debris.
- Description of methods requiring NRC approval for changes that need to be included in the VEGP updated final safety analysis report.
- Discussion of the use of Argonne National Laboratory equations for solubility versus the equations from the University of New Mexico.
- Description of any additional weld inspections to the ones included in the in-service inspection program.
The list above is not all inclusive of the information that needs to be included in the planned submittal. The list only includes the potential gaps that the NRC staff was able to identify from the licensee's presentation.
During its presentation, the licensee highlighted the timing of its planned submittal relative to Westinghouse Electric Company's WCAP-17788, "Comprehensive Analysis and Test Programs for GSl-191 Closure (PA-SEE-1090)," which is a topical report (TR) currently being reviewed by the NRC (ADAMS Package Accession No. ML15210A667). The licensee stated that the submittal relies on some of the methods described in the TR and that it planned to provide its submittal to the NRC prior to the NRC staff completing review of the TR. SNC stated that it plans to submit the license amendment and exemption requests in the first quarter of calendar year 2017 and to request NRC approval by June 2018.
The NRC staff informed the licensee of NRC practice concerning submittals that rely on information in a TR that is currently under review for generic use. Specifically, the NRC staff should not accept a requested licensing action for review until the generic review is completed.
The NRC staff informed SNC that it had three options to avoid non-acceptance of its planned license amendment and exemption requests:
(1) Delay its planned submittal until the review of WCAP-17788 is complete; (2) Include the methods described in WCAP-17788 directly into its planned submittal; or (3) Provide a plant-specific justification, describing an urgent need that cannot wait until review of WCAP-17788 is completed.
With regard to the third option, the NRC staff informed the licensee that it could provide a plant-specific justification prior to its planned submittal for consideration by the NRC staff.
During the meeting, the licensee described how it plans to consider safety margin and operating margin with regard to the evaluation of plant modifications, if the planned license amendment and exemption requests are approved by the NRC. The NRC staff asked the licensee if it planned to request NRC approval of the licensee's method for evaluating plant modifications that could affect GSl-191 "inputs" as part of the licensee's planned submittal. In response, the licensee stated that it was not planning to request NRC approval, but to make the staff aware of its planned approach to evaluating plant modifications that could affect GSl-191 "inputs."
The NRC staff did not make any regulatory decisions during the meeting. Members of the public were in attendance by telephone conference. No comments from the public were received during the meeting. A public meeting feedback form was received.
Please direct any inquiries to me at 301-415-2871 or Michael.Marshall@nrc.gov.
Michael L. Marshall, Jr., Senior Project Manager Plant Licensing Branch 1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-424 and 50-425
Enclosure:
List of Participants cc w/encl: Distribution via Listserv
LIST OF PARTICIPANTS NOVEMBER 29, 2016. MEETING WITH SOUTHERN NUCLEAR OPERATING COMPANY ON PLANNED SUBMITTAL OF VOGTLE ELECTRIC GENERATING PLANT. UNITS 1 AND 2 LICENSE AMENDMENT AND EXEMPTION REQUESTS CONCERNING RESOLUTION OF GENERIC SAFETY ISSUE 191 Ernie Kee Enercon Owen Scott SNC Patrick Romine Enercon Philli Grissom SNC Michael Marshall Michael Markle NRC Vic Cusumano NRC Steve Smith NRC Paul Klein NRC Matt Yoder NRC Mehdi Reisi Fard NRC CJ Fon NRC John Tsao NRC
ML16354A121 Meering Norice: ML16320A073 H an d ou t s: ML16337A298 *b1y e-ma1*1 OFFICE DORL/LPL 1/PM DORL/LPL2-1 /PM DORL/LPL 1/LA DSS/SSIB/BC*
NAME MMarshall MOrenak LRonewicz VCusumano DATE 12/27/2016 12/27/2016 12/27/2016 12/23/2016 OFFICE DRNAPLA/TL
- DORL/LPL2-1 /BC DORL/LPL 1/PM NAME CFong MMarkley MMarshall DATE 12/22/2016 12/27/2016 12/27/2016