ML20289A424

Summary of Public Meeting with Southern Nuclear Operating Company, Inc. Regarding Proposed License Amendment Request to Remove Function 1.f from Technical Specification Table 3.3.6.1A-7 for Hatch, Units 1 and 2

ML20289A424
Person / Time
Site:	Hatch
Issue date:	11/04/2020
From:	John Lamb Plant Licensing Branch II
To:	Gayheart C Southern Nuclear Operating Co
Lamb J
References
EPID L-2020-LRM-0083
Download: ML20289A424 (5)

Text

November 4, 2020 LICENSEE: Southern Nuclear Operating Company, Inc.

FACILITY: Edwin I. Hatch Nuclear Plant, Units 1 and 2

SUMMARY

OF OCTOBER 14, 2020, PUBLIC MEETING WITH SOUTHERN NUCLEAR OPERATING COMPANY, INC., REGARDING A PROPOSED LICENSE AMENDMENT REQUEST TO REMOVE FUNCTION 1.f (MAIN STEAM LINE ISOLATION - TURBINE BUILDING AREA TEMPERATURE -

HIGH) FROM TECHNICAL SPECIFICATION TABLE 3.3.6.1A-7 FOR EDWIN I.

HATCH NUCLEAR PLANT, UNITS 1 AND 2 (EPID L-2020-LRM-0083)

On October 14, 2020, a Category 1 public meeting was held between the U.S. Nuclear Regulatory Commission (NRC) and representatives of Southern Nuclear Operating Company, Inc. (SNC, the licensee). The purpose of the meeting was for SNC to describe its plan to submit a license amendment request (LAR) to remove Function 1.f (Main Steam Line Isolation -

Turbine Building Area Temperature - High) from Technical Specification (TS) Table 3.3.6.1A-7 for Edwin I. Hatch Nuclear Plant (Hatch), Units 1 and 2. SNC plans to place the Function 1.f into the licensee-controlled Technical Requirements Manual (TRM). The meeting notice and agenda, dated September 2, 2020, are available in the Agencywide Documents Access and Management System (ADAMS) at Accession No. ML20247J374. A list of attendees is enclosed.

The SNC presented slides contained in ADAMS Accession No. ML20281A327.

Introduction The NRC staff opened the meeting with introductory remarks and introduced the attendees.

The SNC staff discussed background information on the isolation function and the proposed LAR.

Background

The Hatch TS contains Table 3.3.6.1-1 for Primary Containment Isolation Instrumentation. The first function on the table is Main Steam Line Isolation. Function 1.f is the Turbine Building Area Temperature - High. This Main Steam Line Isolation - Turbine Building Area Temperature -

High Function is applicable in MODES 1, 2, and 3. The Function 1.f, Turbine Building Area Temperature - High, receives input from 64 channels. The inputs are arranged in a one-out-of-thirty-two taken twice logic trip system to isolate all Main Steam Isolation Valves (MSIVs). This Function has 16 required channels per trip system. This means eight channels per trip string.

Each trip string shall have two channels per main steam line, with no more than 40 feet separating any two OPERABLE channels. The TS required surveillance requirements are (1) Perform CHANNEL FUNCTIONAL TEST, (2) Perform CHANNEL CALIBRATION, and (3) Perform LOGIC SYSTEM FUNCTIONAL TEST. The allowable value for the Function is less than or equal to 200 degrees Fahrenheit.

Presentation SNC stated that the Function 1.f detects very small leaks equivalent to between 1 percent and 10 percent of rated steam flow. SNC explained that credit is not taken for these instruments in any transient or accident analysis in the Updated Final Safety Analysis Report (UFSAR). SNC stated that the bounding analyses in the UFSAR is performed for a large break, such as main steam line break. Further, SNC stated that Function 1.c, Main Steam Line Flow - High, provides diversity.

SNC proposed to delete the Function 1.f from TSs and relocate Function 1.f to the licensee-controlled TRM. SNC stated it would maintain the trip function. SNC said it would make changes to Function 1.f using Title 10 of the Code of Federal Regulations (10 CFR), Section 50.59, Changes, tests, and experiments. SNC stated that Function 1.f does not meet any of the 10 CFR 50.36(c)(2)(ii) criteria and SNC cited precedence in that Brunswick Nuclear Station moved this Function to its TRM during an Improved Standard TS conversion.

SNC stated that its proposed LAR will discuss Hatchs ability to detect significant, abnormal degradation of the reactor coolant pressure boundary. SNC stated that its proposed LAR will discuss the fact that turbine building area temperatures are not used as initial temperature in any design-basis accident (DBA). SNC stated that its proposed LAR will discuss that turbine building area temperatures are not credited as the primary success path to mitigate a DBA.

SNC noted that its proposed LAR justification will entail (1) a discussion of risk contribution for steam line break initiating event, (2) a discussion of turbine building high temperature main steam line isolation as part of Hatch probabilistic risk assessment for internal events, internal flooding, internal fires, and seismic events, (3) sensitivity analysis to determine risk-significance for both core damage frequency and offsite releases, and (4) a review of any relevant operating experience (e.g. corrective action program, licensee event report).

NRC Questions to SNC The NRC staff asked if this function is credited for on the secondary side in the UFSAR. The licensee stated it would take a look at the UFSAR and address it in the proposed LAR. The NRC staff asked if there should be any additional TSs added to compensate for Hatch not being a Standard TS plant. The licensee said it performed an analysis last year of the Brunswick TS to the Hatch TS and there did not seem anything related to this, but SNC would look into it.

The NRC staff asked if the proposed LAR would be a risk-informed LAR. SNC stated that it would not be a risk-informed LAR, but it would include risk information. SNC said that it is relying on the Brunswick Improved TS LAR.

The NRC staff asked if the proposed LAR would conflict with the Hatch National Fire Protection Association (NFPA) 805 amendment. SNC said that they would look into it.

The NRC staff asked if the proposed LAR would be impacted by a potential, future power uprate, if requested. SNC explained that there is no power uprate planned for Hatch now or in the future.

The NRC staff asked if moving Function 1.f to the TRM would give SNC the latitude to bypass the system as per the last chiller incident leading to high turbine building temperature. The licensee stated that it would not provide latitude to bypass the system; however, it would allow SNC to change the allowed outage time (AOT) under 10 CFR 50.69. The NRC staff asked if the

chiller incident led to this proposed LAR. SNC acknowledged that the Hatch chiller incident did contribute to evaluating the need for this proposed LAR and it would allow SNC flexibility to provide longer AOT per 10 CFR 50.59 if the function is no longer under control in TS.

Public Questions to NRC There were no members of the public in attendance.

Closing Once received, the NRC staff will perform a thorough review of the proposed LAR and make any regulatory decisions in writing in a timely manner. The NRC staff made no regulatory decisions during the meeting.

Public Meeting Feedback forms were available, but no comments were received.

Please direct any inquiries to me at 301-415-3100.

/RA John G. Lamb, Senior Project Manager Plant Licensing Branch II-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-321 and 50-366

Enclosure:

List of Attendees cc: Listserv

LIST OF ATTENDEES OCTOBER 14, 2020, PUBLIC MEETING WITH SOUTHERN NUCLEAR OPERATING COMPANY, INC.

REGARDING FUNCTION 1.f REMOVAL FROM TECHNICAL SPECIFICATION TABLE 3.3.6.1A-7 EDWIN I. HATCH NUCLEAR PLANT, UNITS 1 AND 2 ATTENDEE REPRESENTING John G. Lamb NRC Mike Markley NRC Brian Wittick NRC Vic Cusumano NRC Rich Smith NRC Joshua Borromeo NRC Zach Stone NRC Mihaela Biro NRC Hanry Wagage NRC Charles Moulton NRC John Parillo NRC Clinton Ashley NRC Ryan Joyce SNC Tim Enfinger SNC Owen Scott SNC Jamie Coleman SNC Jimmy Collins SNC Jason Douglas SNC Richard Davis-Zapata General Electric (GE)

Dan Pappone GE Hoa Hoang GE Kent Halac GE Enclosure

ML20281A326 (Package);

ML20281A327 (Slides);

ML20247J374 (Meeting Notice);

ML20289A424 (Meeting Summary) *via e-mail OFFICE NRR/DORL/LPL2-1/PM* NRR/DORL/LPL2-1/PM* NRR/DORL/LPL2-1/LA*

NAME ZStone JLamb KGoldstein (JBurkhardt for)

DATE 10/14/2020 10/14/2020 10/20/2020 OFFICE NRR/DORL/LPL2-1/BC* NRR/DORL/LPL2-1/PM*

NAME MMarkley* JLamb DATE 11/04/2020 11/04/2020