ML25351A239
| ML25351A239 | |
| Person / Time | |
|---|---|
| Site: | Grand Gulf, Arkansas Nuclear, River Bend, Waterford  |
| Issue date: | 07/28/2025 |
| From: | Michael Mahoney Plant Licensing Branch IV |
| To: | Mahan C Entergy Services |
| Mahoney, M | |
| References | |
| EPID L-2024-LLA-0160 | |
| Download: ML25351A239 (0) | |
Text
From:
Michael Mahoney To:
Mahan, Cecil Cc:
Couture III, Philip
Subject:
Entergy Fleet LAR - OLM - Supplemental Audit Request Date:
Monday, July 28, 2025 8:24:56 AM Attachments:
image001.png Supplemental Audit Request - Entergy OLM LAR.docx Hi Howard,
Attached is a supplemental audit request for the OLM LAR.
Thanks
Mike Mahoney Senior Project Manager, LPL4 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Desk: (301)-415-3867 Mobile: (301)-250-0450 Email: Michael.Mahoney@nrc.gov
SUPPLEMENTAL AUDIT INFORMATION REQUEST ENTERGY FLEET LICENSE AMENDMENT REQUEST TO USE ONLINE MONITORING METHODOLOGY EPID: L-2024-LLA-0160
- 1) Entergy requests to use Measurement and Test Equipment (M&TE), which includes the plant computer, to collect data and check if a transmitter is in need of calibration. Entergy plans to measure how much each transmitter's readings change over time or drift and compare these to a set Online Monitoring (OLM) limit. For certain cases, the drift being measured is very small. However, the documents referenced in the license amendment request (LAR) state that the uncertainties associated with the proposed M&TE to measure these changes may be large.
Please explain how Entergy has determined that the M&TE being proposed, which includes the plant process computer, is capable of reliably measuring the instrument channel drift with an accuracy that will not mask the drift being measured given the associated uncertainty in these configurations. For example, describe how the proposed M&TE, inclusive of digital signal conversion and algebraic presentation, is sufficiently accurate to reliably measure the drift in the transmitters included in the OLM program to support the decision making (for example, see International Society of Automation (ISA)
Recommended Practice 67.04.02, Annex H).