ML22252A043

Summary of August 31, 2022, Webinar with STP Nuclear Operating Company to Discuss a Proposed LAR to Revise the Dose Consequence Analysis for Main Steam Line Break and Locked Rotor Analysis Events for STP, Units 1 & 2

ML22252A043
Person / Time
Site:	South Texas
Issue date:	09/12/2022
From:	Dennis Galvin Plant Licensing Branch IV
To:	South Texas
Galvin D
References
EPID L-2022-LRM-0063
Download: ML22252A043 (4)

Text

September 12, 2022 LICENSEE: STP Nuclear Operating Company FACILITY: South Texas Project, Units 1 and 2

SUMMARY

OF AUGUST 31, 2022, WEBINAR WITH STP NUCLEAR OPERATING COMPANY TO DISCUSS A PROPOSED LICENSE AMENDMENT REQUEST TO REVISE THE DOSE CONSEQUENCE ANALYSIS FOR MAIN STEAM LINE BREAK AND LOCKED ROTOR ANALYSIS EVENTS FOR SOUTH TEXAS PROJECT, UNITS 1 AND 2 (EPID L-2022-LRM-0063)

On August 31, 2022, an Observation public meeting, conducted as a webinar, was held between the U.S. Nuclear Regulatory Commission (NRC) staff and representatives of the STP Nuclear Operating Company (the licensee). The purpose of the meeting was to discuss a proposed license amendment request to revise the dose consequence analysis for main steam line break (MSLB) and locked rotor analysis (LRA) events for South Texas Project, Units 1 and 2. The revised analysis would increase the cooldown timelines from 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> to 28 hours3.240741e-4 days <br />0.00778 hours <br />4.62963e-5 weeks <br />1.0654e-5 months <br /> to address the slower cooldown rate in an asymmetric natural circulation scenario. The meeting notice and agenda, dated August 17, 2022, are available in the Agencywide Documents Access and Management System (ADAMS) at Accession No. ML22229A487. A list of attendees is enclosed.

The licensee presented informational slides at the meeting, which can be found in ADAMS at ML22243A131. During the meeting, the licensee described how it plans to reanalyze the MSLB and LRA events with extended cooldown times as a result of asymmetric natural circulation cooldown, which results in less cooling in the steam generators. The licensee also described how it plans to use the dose analysis codes in SNAP/RADTRAD 5.0.2 instead of RADTRAD 3.03. The licensee also identified planned modeling differences. The NRC staff and the licensee discussed the above topics. The NRC staff provided feedback on the information needed for a complete application, including describing how any analytical or modeling differences are consistent with regulatory guidance, in particular, Regulatory Guide 1.183, Alternative Radiological Source Terms for Evaluating Design Basis Accidents at Nuclear Power Reactors (ML003716792).

No members of the public called into the meeting. No regulatory decisions or commitments were made at the meeting. Additionally, the NRC staff did not receive Public Meeting Feedback forms.

Please direct any inquiries to me at 301-415-6256 or by email at Dennis.Galvin@nrc.gov.

/RA/

Dennis J. Galvin, Project Manager Plant Licensing Branch IV Division of Operator Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-498 and 50-499

Enclosure:

List of Attendees cc: Listserv

LIST OF ATTENDEES AUGUST 31, 2022, PRESUBMITTAL WEBINAR REGARDING PROPOSED LICENSE AMENDMENT REQUEST TO REVISE THE DOSE CONSEQUENCE ANALYSIS FOR MAIN STEAM LINE BREAK AND LOCKED ROTOR ANALYSIS EVENTS STP NUCLEAR OPERATING COMPANY SOUTH TEXAS PROJECT, UNITS 1 AND 2 U.S. Nuclear Regulatory Commission S. Bhatt D. Galvin S. Meighan STP Nuclear Operating Company W. Brost H. Chen Q. Duong N. Hall T. Hammons J. Thyrion M. Whitley Dominion B. Mount Enclosure

ML22252A043 OFFICE NRR/DORL/LPL4/PM NRR/DORL/LPL4/LA* NRR/DSS/SNSB/BC(A)

NAME DGalvin PBlechman DWoodyatt DATE 9/9/2022 9/9/2022 9/8/2022 OFFICE NRR/DRA/ARCB/BC NRR/DORL/LPL4/BC NRR/DORL/LPL4/PM NAME KHsueh JDixon-Herrity DGalvin DATE 9/8/2022 9/10/2022 9/12/2022