ML22144A390

RCP Seal Solutions - May 24 2022 Slide Material (Public)

ML22144A390
Person / Time
Site:	Turkey Point
Issue date:	05/24/2022
From:	Moul D Florida Power & Light Co
To:	NRC/NRR/DORL/LPL2-2
Mahoney M
Shared Package
ML22144A387	List: ML22144A390 ML22144A392
References
Download: ML22144A390 (20)

Text

Turkey Point Unit 3 and Unit 4 License Amendment Request: Revise Fire Protection Program in Support of Reactor Coolant Pump Seal Replacement Project May 24, 2022 CLOSED SESSION 1

Agenda -Closed Session

• Purpose

• Approach to Address Fire Risk Increase

• PRA Risk Increase Between Current and New RCP Seals

• Data Supporting RCP Seal Failure Model

• Schedule

• Questions and Comments 2 Non-proprietary information suitable for public disclosure

Purpose

• Gain agreement for licensing approach for post NFPA 805 transition LAR

• Request NRC input regarding review schedule

- Additional information provided re: risk analysis

- Discuss support for NRC review 3 Non-proprietary information suitable for public disclosure

Approach to Address Fire Risk Increase

- Approach is to re-establish baseline risk associated with NFPA 805 transition and transition change in risk Current RCP seal change is an evolution of the required NFPA 805 RCP seal modification

- Flowserve NX seal was an NFPA 805 required modification

- Due to operational concerns, another seal type needs to be pursued that meets NFPA 805 requirements and operational considerations 4 Non-proprietary information suitable for public disclosure

Approach to Address Fire Risk Increase

- The NFPA 805 LAR evaluated the change in fire risk as a combined change request The increase in risk associated with retained Variances from Deterministic Requirements (VFDRs) was offset by the reduction in risk associated with modifications not required for deterministic compliance A similar approach will be used for the RCP seal modification LAR considering total NFPA 805 delta risk and the risk offsets addressed in the NFPA 805 LAR

- Use 2016 NRC guidance for changes to NFPA 805 license conditions (ML16015A416)

Although Turkey Point has completed transition, the guidance is helpful for LAR content Using Option B from the NRC guidance 5 Non-proprietary information suitable for public disclosure

PRA Risk Increase Between Current and New RCP Seals

• Reason for Risk Increase

- Seal failure data is based on evaluation of potential failure modes, operational experience and testing

- System time window for RCP trip for total loss of seal cooling is than with the current seal 20 minutes for current seal To be addressed in updated Human Reliability Analysis 6 Non-proprietary information suitable for public disclosure

PRA Risk Increase Between Current and New RCP Seals

• Updated guidance used in this application that was not part of the original Turkey Point NFPA 805 LAR 7 Non-proprietary information suitable for public disclosure

PRA Risk Increase Between Current and New RCP Seals

• PRA modeling refinements for this application to provide more realistic risk characterization 8 Non-proprietary information suitable for public disclosure

PRA Risk Increase Between Current and New RCP Seals

• No PRA upgrades or new methods are currently anticipated 9 Non-proprietary information suitable for public disclosure

Data Supporting RCP Seal Failure Model

• Testing

- Testing of the PSDS included actuation of the PSDS and testing of the seals ability to remain sealed after actuation

• Methods Used

• Operating Experience

- The Framatome PSDS is currently installed at one US site and multiple international sites.

10 Non-proprietary information suitable for public disclosure

Schedule

• LAR submittal scheduled for Summer 2022

• Installation scheduled for U4 fall 2023 outage

• Support for NRC review

- Portal for information availability

- Audit support

- Additional meetings as needed to discuss proprietary information 11 Non-proprietary information suitable for public disclosure

Questions and Comments 12 Non-proprietary information suitable for public disclosure