ML21300A277
| ML21300A277 | |
| Person / Time | |
|---|---|
| Site: | Limerick  |
| Issue date: | 11/09/2021 |
| From: | Bhagwat Jain Plant Licensing Branch 1 |
| To: | Rhoades D Exelon Nuclear, Exelon Generation Co |
| Jain B | |
| References | |
| EPID L-2020-LRM-0041 | |
| Download: ML21300A277 (6) | |
Text
November 9, 2021 LICENSEE: Exelon Generation Company, LLC FACILITY: Limerick Generating Station, Units 1 and 2
SUBJECT:
SUMMARY
OF OCTOBER 20, 2021, PRE-SUBMITTAL PUBLIC MEETING WITH EXELON GENERATION COMPANY, LLC REGARDING PLANNED DIGITAL MODERNIZATION LICENSE AMENDMENT REQUEST FOR LIMERICK GENERATING STATION, UNITS 1 AND 2 (EPID L-2020-LRM-0041)
On October 20, 2021, a pre-submittal public meeting via TEAMS was held between the U.S. Nuclear RegulatoryCommission (NRC) and representatives of Exelon Generation Company, LLC (Exelon, the licensee). The purpose of the meeting was to discuss Exelons plan to submit a license amendment request (LAR) involving the modernization of instrumentation and control (I&C) systems at Limerick Generating Station (Limerick), Units 1 and 2 and to understand how the proposed changes will address fundamental I&C design principles and regulatory requirements. The meeting notice and agenda, dated September 9, 2021, are available in the Agencywide Documents Access and Management System (ADAMS) at Accession No. ML21289A000. The meeting was partially closed, because some of the information discussed during the meeting was proprietary in nature. The non-proprietary presentation used during the meeting is available in ADAMS at Accession No. ML21278A545. The NRC staff sent questions to the licensee prior to the meeting. The list of questions is available in ADAMS at Accession No. ML21286A030. The proprietary presentation used during the meeting is available in ADAMS at Accession No. ML21295A019 (non-public). A list of attendees is enclosed.
The licensee provided an overview of the planned digital I&C modernization project at Limerick and an overview of the planned license amendment request. In addition to replacing analog safety systems with a digital safety system, the licensee plans on replacing and combining the reactor protection system, nuclear steam supply shutoff system, and emergency core cooling system into a single digital plant protection system using the Westinghouse Common Q technology. The licensee discussed details of the proposed I&C architecture including combination of systems, reduction in sensors, defense-in-depth and diversity, spurious actuation, and probabilistic risk assessment.
The licensee plans to include the following in its license amendment request:
Required information listed in Enclosure B, Information Provided in Support of a License Amendment Request for a Digital Instrumentation and Control Modification, of DI&C-ISG-06, Licensing Process (December 2018).
Licensing technical report
Description of technical specification changes Description of system requirements specification Description of system design specification Summary of equipment qualifications Summary of human factors Summary of vendor oversight program Summary of defense-in-depth and diversity analysis Conceptional mark-ups of final safety analysis report Regulatory commitments In the closed portion of the meeting, the licensee discussed proprietary details of the Common Q technology, planned system integration, allocation of sensors, defense-in-depth and diversity approach, and spurious actuation analysis. Also, the licensee specifically addressed the questions NRC staff sent to the licensee prior to the meeting on the consolidation of systems, reduction in sensors, and probabilistic risk assessment.
During the discussion of the digital I&C modernization project, the NRC staff informed the licensee that planned review duration assumption should be 2 months for the acceptance review and 15 months for the detailed review. In response to a question from the NRC staff, the licensee stated that its defense-in-depth and diversity (D3) analysis and evaluation will be provided to the staff early in the first quarter of CY 2022 and will discuss technical specification changes in a separate meeting with the staff later. In response to a question from the NRC staff, the licensee representative stated that the plant protection system is designed to have a power supply that is not susceptible to common cause failure and that each cabinet will have a redundant power supply. The licensee stated that it will discuss the details of cabinet power supply configuration in the next pre-application meeting. The NRC staff informed the licensee that the following should be included in its application:
The licensee should either state the reliability goal for the proposed system or provide a comparison of the reliability of the current systems and proposed system in the planned LAR.
The licensee should include a summary of the planned reliability analysis in the planned LAR.
The next pre-application meeting will be scheduled in the first quarter of CY 2022. The licensee informed that it would discuss updates to the project status, human factors engineering, the vendor oversight plan, technical specifications, and other specific follow-up items discussed during the closed portion of the meeting.
No regulatory decisions were made during the meeting. No members of the public were in attendance.
Please direct any inquiries to me at 301-415-6303 or Bhagwat.Jain@nrc.gov
/RA/
Bhagwat Jain, Senior Project Manager Plant Licensing Branch IV Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-352 and 50-353
Enclosure:
List of Attendees cc: Listserv
LIST OF ATTENDEES OCTOBER 20, 2021, PUBLIC MEETING WITH EXELON GENERATION COMPANY, LLC LIMERICK GENERATING STATION, UNITS 1 AND 2 PROPOSED LICENSE AMENDMENT REQUEST INVOLVING DIGITAL MODERNIZATION Name Organization Aaron Armstrong U.S. Nuclear Regulatory Commission (NRC)
Bhagwat Jain NRC David Rahn NRC Deanna Zhang NRC Eric Benner NRC Greg Galletti NRC Jack Zhao NRC Jesse Seymour NRC Justin Vazquez NRC Khadijah West NRC Michael Marshall NRC Michael Waters NRC Dumont, Louis NRC Region 1 Steven Alferink NRC Richard Stattel NRC Robert Beaton NRC Rossnyev Alvarado NRC Samir Darbali NRC Shilp Vasavada NRC Tarico Sweat NRC Craig Myers Exelon Generation Company, LLC (Exelon)
Dave Helker Exelon Dave Molteni Exelon David Peiffer Exelon Elliott Flick Exelon Frank Mascitelli Exelon George Bonanni Exelon George Budock Exelon Joe Drahus Exelon Jerry Segner Exelon John Connelly Exelon Kayla Marriner Exelon Mark Samselski Exelon Michael Foote Exelon Paul Krueger Exelon Parthiv Desai Exelon Preeti Furtado Exelon Scott Schumacher Exelon Enclosure
Name Organization Steven Hesse Exelon Suzanne Loyd Exelon Vikram Shah Exelon Ballert Zachary Exelon Contractor Pareez Golub Sargent & Lundy Brian Mann Excel services Paul Hunton Department of Energy Calvin Tang Westinghouse Christopher Crefeld Westinghouse Maria Assard Westinghouse Stephen Seaman Westinghouse Steven Merkiel Westinghouse Terrence Tuite Westinghouse Warren Odess Gillett Westinghouse
ML21300A277 OFFICE NRR/DORL/LPL4/PM NRR/DORL/LPL1/LA NRR/DEX/EICB/BC NAME BJain KZeleznock MWaters DATE 11/01/2021 10/29/2021 11/01/2021 OFFICE NRR/DORL/LPL1/BC NRR/DORL/LPL4/PM NAME JDanna BJain DATE 11/08/2021 11/09/2021