ML21161A299

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Summary of May 18, 2021 Public Webinar with Nextera Energy Point Beach, LLC Regarding Path Forward for Generic Letter 2004-02 Closure
ML21161A299
Person / Time
Site: Point Beach  NextEra Energy icon.png
Issue date: 06/17/2021
From: Booma Venkataraman
Plant Licensing Branch III
To:
Point Beach
Venkataraman B, NRR/DORL/LPL3, 415-2934
References
EPID L-2017-LRC-0000
Download: ML21161A299 (5)


Text

June 17, 2021 LICENSEE: NextEra Energy Point Beach, LLC.

FACILITY: Point Beach Nuclear Plant, Units 1 and 2

SUBJECT:

SUMMARY

OF MAY 18, 2021 PUBLIC WEBINAR WITH NEXTERA ENERGY POINT BEACH, LLC REGARDING PATH FORWARD FOR GENERIC LETTER 2004-02 CLOSURE FOR POINT BEACH NUCLEAR PLANT (EPID L-2017-LRC-0000)

On May 18, 2021, an observation public meeting was held between the U.S. Nuclear Regulatory Commission (NRC) staff and representatives of NextEra Energy Point Beach, LLC (NextEra, the licensee) via a webinar. The purpose of the meeting was for NextEra to discuss with the NRC staff a path forward for Generic Letter (GL) 2004-02 closure for the Point Beach Nuclear Plant, Units 1 and 2 (Point Beach). Specifically, NextEra wanted to discuss its overall methodology, results from a preliminary assessment, its proposed risk-informed approach to GL 2004-02 closure and its planned submittal schedule. In addition, NextEra planned to briefly discuss with the NRC staff the status of the Point Beach probabilistic risk assessment (PRA) in the context of a risk-informed approach to GL 2004-02 closure.

The meeting notice and agenda dated May 5, 2021, are available in the Agencywide Documents Access and Management System (ADAMS) at Accession No. ML21137A278.

NextEras slide presentation associated with the meeting is available at ADAMS Accession No. ML21134A023. A list of attendees is enclosed.

NextEra Presentation NextEra provided an introduction of the Point Beach Westinghouse 2-loop pressurized-water reactor layout, including a description of the safety-related emergency core cooling systems and the containment sump strainer arrangement and the factors affecting strainer performance.

NextEra also provided the history and background of the issue and indicated it submitted its response to the GL 2004-02 in 2017, and the NRC staff conducted an audit in 2019, with an audit report dated December 2, 2019 (ADAMS Accession No. ML19217A003) on the issues.

NextEra further indicated that it was able to address the NRC staffs questions, except for the questions regarding the issue with the structural strength of the mineral wool cassettes. The licensee stated that they have identified a path forward to address the mineral wool cassette issue. NextEra indicated that they conducted an analysis to determine the best path forward for closeout of GL 2004-02. Considering several options, NextEra indicated its plan to use a risk-informed resolution approach, using methodology accepted by NRC staff and referring to precedence applications at South Texas Project and Vogtle. NextEra indicated that the risk-informed approach would address the NRC concerns in the 2019 NRC audit report.

NextEra provided details regarding the proposed updates to the debris generation analysis which used BADGER computer aided design models for the debris generation calculation.

NextEra also highlighted the proposed risk quantification approach and indicated that based on preliminary evaluations of the initiating events, NextEra expects only large loss-of-coolant

accidents (LOCAs) and secondary side breaks will contribute to the risk associated with LOCA-generated debris, and secondary side breaks will be addressed using a bounding approach with internal PRA models for risk-quantification. Further NextEra discussed how it planned to address seismically-induced LOCAs and highlighted that based on its assessment, the risk contribution of seismically-induced LOCAs on strainer performance would be negligible.

NextEra also indicated that it plans to evaluate the postulated breaks against failure criteria (e.g., strainer head loss exceeds pump net positive suction head (NPSH) margin) using software called NARWHAL. The analysis will include risk quantification, uncertainty evaluations, and sensitivity analysis.

NextEra indicated its plan to submit its response to GL-2004-02 in the spring of 2022, and will address the five principles of Regulatory Guide (RG) 1.174. The submittal will include a license amendment request to implement the proposed risk-informed approach to address the sump strainer issue, and request to seek exemption for Title 10 of the Code of Federal Regulations Section 50.46 (a) (1).

NextEra also discussed the Point Beach PRA model, and the recently completed risk-informed applications. The licensee indicated that the current PRA model assumptions are not expected to have any impact on the risk-informed resolution proposed for Point Beach for GL 2004-02.

Staff Discussion The NRC staff asked clarifying questions of the licensee during the presentation. The NRC staff indicated that details regarding the robustness of the mineral wool cassettes within the zone of influence, should be addressed in the submittal. The NRC staff also indicated that licensees qualitative assessment should be included in the submittal for seismically-induced LOCAs. The NRC staff also commented that the licensees upcoming submittal should address NPSH margin for void fraction that may occur at the pump suctions due to degasification. The NRC staff also provided a comment that it would be beneficial to include any assessment from the Point Beach PRA model in the LAR submittal.

Public Comments There were two members of the public, Mr. Michael Keegan (Dont Waste Michigan) and Jan Boudart (Nuclear Energy Information Service) in attendance. A summary of the public comments is provided below.

x Mr. Michael Keegan (Dont Waste Michigan) asked the NRC staff details of the debris, the frequency and schedule of inspections on the sump strainers. The NRC staff indicated that the licensee has implemented administrative controls to ensure that potential debris sources inside containment are controlled and remain within the limits defined in the plant analyses. The containment is inspected at the end of every outage to ensure that foreign materials have been removed and significant amounts of latent debris (dirt and dust) are removed.

At this meeting, the NRC staff made no regulatory decisions regarding the merits of the proposed path forward presented by NextEra.

The meeting was adjourned at 2:05 p.m. No Public Meeting Feedback forms were received.

Please direct any inquiries to Booma Venkataraman at (301) 415-2934 or Booma.Venkataraman@nrc.gov.

Docket Nos. 50-266 and 50-301

Enclosure:

List of Attendees cc: Listserv

LIST OF ATTENDEES MAY 18, 2021, PUBLIC WEBINAR TO DISCUSS PATH FORWARD FOR GENERIC LETTER 2004-02 CLOSURE FOR POINT BEACH NUCLEAR PLANT UNITS 1 AND 2 NEXTERA ENERGY POINT BEACH, LLC POINT BEACH NUCLEAR PLANT DOCKET NOS. 50-266 and 50-301 Name Organization U. S. Nuclear Regulatory Commission (NRC) Participants Nancy Salgado NRC Victor Cusumano NRC Booma Venkataraman NRC Steve Smith NRC Andrea Russell NRC Ravi Grover NRC Justin Poole NRC Robert Vettori NRC Michelle Kichline NRC Bill Rogers NRC Antonios Zoulis NRC Lauren Gibson NRC John Hanna NRC Tom Hartman NRC Matthew Yoder NRC Steven Bloom NRC Jackie Harvey NRC Shilp Vasavada NRC Prema Chandrathil NRC Paul Klein NRC Scott Burnell NRC Licensee Participants Jarrett Mack NextEra Steve Catron NextEra Anil Julka NextEra Jon Leiker NextEra Steven Bach NextEra Lloyd Hawki NextEra Eric Schulz NextEra Tom Schneider NextEra Haifeng Lee Enercon Tim Sande Enercon Paul Leonard Enercon Members of Public Mike Keegan Dont Waste Michigan Jan Boudart Nuclear Energy Information Service Enclosure

ML21161A299 *by e-mail OFFICE NRR/DORL/LPL3/PM NRR/DORL/LPL3/LA* NRR/DORL/LPL3/BC*

NAME BVenkataraman SRohrer NSalgado DATE 05/28/2021 06/14/2021 06/16/2021 OFFICE NRR/DORL/LPL3/PM*

NAME BVenkataraman DATE 06/17/2021