ML24079A238
| ML24079A238 | |
| Person / Time | |
|---|---|
| Site: | Braidwood  |
| Issue date: | 03/19/2024 |
| From: | NRC/RGN-III/DORS/EB1 |
| To: | |
| References | |
| EA-24-003 | |
| Download: ML24079A238 (1) | |
Text
U.S. Nuclear Regulatory Commission Public Meeting Summary
Title:
Regulatory Conference with Constellation Nuclear Regarding Braidwood Station, Unit 2 EA:EA-24-003 Date of Meeting:March 7, 2024 Location:U.S. Nuclear Regulatory Commission - Region III Main Conference Room 2443 Warrenville Rd, Suite 201 Lisle, IL 60532 Webinar (via Microsoft Teams)
Type of Meeting:Observation Meeting with a Question-and-Answer Session Purpose of Meeting:
The purpose of this Regulatory Conference is to discuss the risk significance of a preliminarily greater than green finding and an associated apparent violation involving an apparent failure to identify and correct a fuel oil leak on the 2B auxiliary feedwater pump diesel engine for approximately 127 days. The preliminary finding and apparent violation are discussed in NRC Inspection Report 05000457/2023011, dated January 23, 2024 (NRCs Agencywide Documents Access and Management System [ADAMS] Accession No. ML24022A100).
NRC
Participants:
Mohammed Shuaibi, Deputy Regional Administrator Russell Felts, Director, Division of Reactor Oversight, Office of Nuclear Reactor Regulation Jason Kozal, Director, Division of Operating Reactor Safety (DORS)
Diana Betancourt-Roldan, Enforcement/Investigations Officer Shelbie Lewman, Regional Counsel Karla Stoedter, Chief, Engineering Branch 1, DORS Richard Skokowski, Chief, Reactor Projects Branch 3, DORS Others as designatedMarch 19, 2024 Licensee
Participants:
Marri Marchionda-Palmer, Senior Vice President, Operations Frank Sturniolo, Senior Vice President, Governance and Oversight Greg Gugle, Site Vice President, Braidwood David Gullott, Vice President Licensing and Regulated Programs Donnie Hudak, Plant Manager, Braidwood Steve Macartney, Director Engineering, Braidwood Kevin Mores, Senior License Holder and Operations Senior Manager, Braidwood Others as designated
General Details:
During routine inspection activities performed in September 2023, the Braidwood resident inspectors became aware that diesel fuel was leaking into the lubricating oil for the 2B auxiliary feedwater pumps diesel engine. Additional inspection activities identified the fuel leak began in May 2023 after the licensee performed maintenance on the 2B auxiliary feedwater pumps diesel engine. The inspectors also found the licensee had taken a lubricating oil sample from the diesel engine in May 2023 and sent the sample to an independent laboratory for analysis. When the licensee received the lubricating oil sample results in June 2023, the results showed the lubricating oils viscosity was not within the expected range. However, the licensee took no action to identify and document the fuel leak within their corrective action program. In addition, no action was taken to stop the fuel leak until September 2023.
The inspectors and Region IIIs senior reactor analysts evaluated the risk associated with the licensees failure identify and correct the fuel leak for approximately 127 days and concluded the risk was preliminarily greater than of very low safety significance (i.e.,
preliminarily greater than green). As a result, the licensee was provided an opportunity (as discussed in the cover letter to NRC Inspection Report 05000457/2023011) to provide additional information to the NRC in writing or to request a Regulatory Conference to discuss the issue with the NRC as part of a public meeting. On February 2, 2024, Constellation Nuclear informed Karla Stoedter, USNRC Region III Branch Chief, of their official request to attend a Regulatory Conference.
Summary of Presentation:
Jason Kozal of the NRC opened the meeting, introduced the purpose of a Regulatory Conference, and informed the public of the opportunity to ask questions of the NRC meeting participants once the Regulatory Conference was complete.
Diana Betancourt-Roldan provided a summary of the NRCs Enforcement Policy, and Karla Stoedter provided an overview of the apparent violation and preliminary risk significance. Jason Kozal then turned the meeting over to Greg Gugle, Braidwood Station Site Vice President, and other representatives of Constellation Nuclear.
Greg Gugle indicated Constellation Nuclear agreed that Braidwood Stations failure to identify and correct the fuel leak on the 2B auxiliary feedwater pumps diesel engine after receiving the results of the May 2023 lubricating oil sample was a performance deficiency as documented in NRC Inspection Report 05000457/2023011. However, Constellation Nuclear asserted the risk associated with the performance deficiency should be characterized as very low safety significance (i.e., Green) because all of the
2 Mitigating Systems Screening Questions provided in NRC Inspection Manual Chapter 0609, Appendix A, Exhibit 2A should be answered No. Specifically, Constellation Nuclear described testing they performed, in conjunction with MPR Associates and Southwest Research Institute, on a similar diesel engine manufactured by Detroit Diesel.
This testing demonstrated the engines ability to run for 24.5 hours5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br /> with a comparable fuel leak into the engines lubricating oil. Constellation Nuclear also discussed the similarities between the tested diesel engine and the 2B auxiliary feedwater pump diesel engine installed at Braidwood Station. Due to the similarities between the two engines and the fact that the tested engine operated for more than 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, Constellation Nuclear stated the NRC must consider the diesel engine test results as part of the best available information used to evaluate the operability and/or functionality of Braidwood Stations 2B auxiliary feedwater pump diesel engine and to determine the final risk significance of the documented performance deficiency.
Constellation Nuclear concluded their presentation by stating that the fuel leaking into the 2B auxiliary feedwater pumps diesel engine lubricating oil should not be considered a loss of safety function or a loss of probabilistic risk assessment (PRA) function because the diesel engine testing performed at Southwest Research Institute demonstrated the engines ability to operate for the 24-hour mission time assumed in the PRA. Constellation Nuclear also indicated that any subsequent risk evaluations performed to assess the risk of this issue should utilize an engine failure probability as close as possible to the PRA assumed baseline engine failure probability since the test engine operated beyond 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. Lastly, Constellation Nuclear indicated any subsequent risk assessments for this issue should provide credit for the aligning the medium head FLEX pump to the refueling water storage tank since procedures exist to direct medium head FLEX pump installation, operators are trained on the installation actions, and adequate time is available to complete medium head FLEX pump installation.
Following Constellation Nuclears presentation, the NRC took a short break to internally caucus and to identify any additional information the Agency needed from Constellation Nuclear prior to making a final decision. After caucusing, the NRC resumed the Regulatory Conference and provided Constellation Nuclear with approximately ten items needing additional information. Most of these items were related to plant specific engine information, lubricating oil sampling limitations, and specific data obtained during the testing performed at Southwest Research Institute. The NRC requested, and the licensee agreed, the information would be provided to the NRC on or before March 17, 2024.
Closing:
Jason Kozal and Mohammed Shuaibi provided closing comments and thanked the NRC staff for their work to support the Regulatory Conference and the licensees staff for providing an informative presentation.
Action Items/Next Steps:
The NRC planned to make and document their final decision regarding risk significance and enforcement action by May 16, 2024.
3 Public Feedback and Questions:
No feedback or questions were provided by the public attending the Regulatory Conference.
Related Documents:
ML24060A169 - NRC Slides for March 7, 2024, Regulatory Conference with Constellation Nuclear Regarding Braidwood
ML24057A303 - Braidwood Station Regulatory Conference Information
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