ML20247J382
| ML20247J382 | |
| Person / Time | |
|---|---|
| Site: | Harris  |
| Issue date: | 09/03/2020 |
| From: | Michael Mahoney Plant Licensing Branch II |
| To: | Earp D Duke Energy Progress |
| Mahoney M | |
| References | |
| EPID L-2020-LLA-0045 | |
| Download: ML20247J382 (3) | |
Text
From:
Mahoney, Michael To:
Dennis Earp (dennis.Earp@duke-energy.com)
Cc:
Art Zaremba
Subject:
Request for Additional Information - Shearon Harris Nuclear Power Plant, Unit 1 - Revise TS Related to Accident Monitoring and RFO Instrumentation (EPID L-2020-LLA-0045)
Date:
Thursday, September 03, 2020 8:33:06 AM Attachments:
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- Dennis,
By letter dated March 12, 2020, as supplemented by letter dated June 22, 2020 (Agencywide Documents Access and Management System (ADAMS) Accession Nos.
ML20072M618 and ML20174A639, respectively), Duke Energy Progress, LLC (the licensee) submitted a license amendment request (LAR) for Shearon Harris Nuclear Power Plant (Harris), Unit 1.
The amendment would revise technical specifications (TS) 3.3.3.6, Accident Monitoring Instrumentation, to change the allowed outage time for inoperable post-accident monitoring (PAM) instrumentation, eliminate the shutdown requirement for inoperable PAM instruments when the minimum required channels are operable, and add a provision that allows a separate entry for each instrument function. The licensee is also proposing to revise TS 3.9.2, Instrumentation, to remove the audible indication requirement in Mode 6, as well as to revise the Note in TS 3.9.2 to allow for the substitution of Wide Range Neutron Flux Monitors (WRNFMs) for both of the Source Range Neutron Flux Monitors (SRNFMs),
required to be operable while in Mode 6.
In order to complete its review, the U.S. Nuclear Regulatory Commission staff requests additional information. A clarification call to ensure mutual understanding was conducted on September 2, 2020. Please provide your response to the following requests for additional information (RAIs) within 30 days of the date of this correspondence.
RAI - 1
Regulatory Basis
The NRC staff identified the following regulatory requirements as being applicable to the proposed amendment:
The NRC's regulatory requirements related to the content of the TSs are set forth in Title 10 of the Code of Federal Regulations (10 CFR) Section 50.36, "Technical specifications." This regulation requires that the TSs include items in the following five specific categories: (1) safety limits, limiting safety system settings, and limiting control settings; (2) limiting conditions for operation; (3) surveillance requirements (SRs); (4) design features; and (5) administrative controls. The regulation does not specify the particular requirements to be included in plant TSs.
Section 50.36(c)(2)(i) of 10 CFR states, in part:
Limiting conditions for operation (LCOs) are the lowest functional capability or performance levels of equipment required for safe operation of the facility. When a limiting condition for operation of a nuclear reactor is not
met, the licensee shall shut down the reactor or follow remedial action permitted by the technical specifications until the condition can be met.
10 CFR Part 50 Appendix A, General Design Criterion (GDC) 13 states:
Instrumentation shall be provided to monitor variables and systems over their anticipated ranges for normal operation, for anticipated operational occurrences, and for accident conditions as appropriate to assure adequate safety, including those variables and systems that can affect the fission process, the integrity of the reactor core, the reactor coolant pressure boundary, and the containment and its associated systems. Appropriate controls shall be provided to maintain these variables and systems within prescribed operating ranges.
The NRC staff considered the following guidance during its review:
- NUREG-1431, Revision 4, "Standard Technical Specifications, Westinghouse Plants," April 2012 (ADAMS Accession No. ML12100A222).
- Regulatory Guide (RG) 1.97, Revision 3, "Instrumentation for Light-Water-Cooled Nuclear Power Plants to Assess Plant and Environs Conditions During and Following an Accident," May 1983 (ADAMS Accession No. ML003740282).
Discussion
In Section 2.3, Reasons for the Proposed Change of letter dated March 12, 2020, the licensee discusses its proposed change to modify the TS 3.9.2 Note to permit both SRNFMs to be substituted with WRNFMs, provided that the Neutron Flux Monitors are located on opposite sides of the core. This proposed change would be applicable during Mode 6 (Refueling). In Section 3.0, Technical Evaluation of letter dated March 12, 2020, the licensee states that the WRNFM provides the same level of quality assurance, redundancy, and necessary display range as the SRNFM. The licensee specifies the neutron sensitivity of both the SRNFMs and WRNFMs but does not provide any further discussion on the performance of the WRNFMs in comparison to the SRNFMs.
Request
- a. Please describe the equivalence of performance of WRNFM and SRNFM channels in Mode 6.
- b. Clarify if the WRNFM channels are as capable as the SRNFM channels in their ability to detect the onset of neutron activity. For example, clarify if the minimum detectable neutron activity for the WRNFM channels is the same as for the SRNFM channels. If not, provide justification as to why the WRNFM channels may be considered acceptable substitutes for the SRNFM channels in Mode 6.
Once this email is added to ADAMS, I will provide the accession number for your reference.
If you have any questions, please contact me.
Thanks Mike
Michael Mahoney McGuire and Catawba Project Manager, Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation U. S. Nuclear Regulatory Commission Desk: (301)-415-3867 Email: Michael.Mahoney@NRC.GOV