05000368/LER-2021-001, Non-Compliance with Technical Specifications Resulting in Lack of Nuclear Instrumentation Audible Indication
| ML21323A180 | |
| Person / Time | |
|---|---|
| Site: | Arkansas Nuclear  |
| Issue date: | 11/19/2021 |
| From: | Keele R Entergy Operations |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| 2CAN112101 LER-2021-001-00 | |
| Download: ML21323A180 (5) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications |
| 3682021001R00 - NRC Website | |
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2CAN112101 November 19, 2021 ATTN: Document Control Desk U. S. Nuclear Regulatory Commission Washington, DC 20555-0001
Subject:
Licensee Event Report 50-368/2021-001-00, Non-Compliance with Technical Specifications Resulting in Lack of Nuclear Instrumentation Audible Indication Arkansas Nuclear One - Unit 2 NRC Docket No. 50-368 Renewed Facility Operating License No. NPF-6 Pursuant to the reporting requirements of 10 CFR 50.73, attached is the subject Licensee Event Report concerning non-compliance with the nuclear instrumentation audible indication in the control room required by Arkansas Nuclear One, Unit 2 Technical Specification 3.9.2 which occurred on October 1, 2021.
There are no new commitments contained in this submittal. Should you have any questions concerning this issue, please contact Riley D. Keele Jr., Manager, Regulatory Assurance, at 479-858-7826.
Respectfully, ORIGINAL SIGNED BY RILEY D. KEELE, JR.
Riley D. Keele, Jr.
RDK/nbm Enclosure: Licensee Event Report 50-368/2021-001-00 Entergy Operations, Inc.
1448 S.R. 333 Russellville, AR 72802 Tel 479-858-7826 Riley D. Keele, Jr.
Manager - Regulatory Assurance Arkansas Nuclear One
2CAN112101 Page 2 of 2 cc:
NRC Region IV Regional Administrator NRC Senior Resident Inspector - Arkansas Nuclear One NRC Project Manager - Arkansas Nuclear One
Enclosure to 2CAN112101 Licensee Event Report 50-368/2021-001-00
Abstract
On October 1, 2021, at Arkansas Nuclear One, Unit 2 (ANO-2) it was discovered that the audible counts for the source range nuclear instrumentation could not be heard in the control room as required by ANO-2 Technical Specification 3.9.2 during Mode 6, Refueling. The volume for the audible indication in the control room was turned down to a setting that could not be heard in the control room. Prior to entering Mode 6, the audible counts for both the containment building and the control room were verified to be operable. The checklist utilized for audible count verification incorrectly specified a mode of applicability for the audible indication of during fuel movement instead of Mode 6 which conflicted with the ANO-2 Technical Specifications. The cause of the event was determined to be inadequate procedural guidance which has been corrected.
There were no consequences to the safety of the general public, nuclear safety, industrial safety or radiological safety created by this event.
PLANT STATUS Arkansas Nuclear One, Unit 2 (ANO-2) was shut down for a refueling outage and in Mode 6. There were no other structures, systems, or components that were inoperable at the time that contributed to the event.
EVENT DESCRIPTION
On October 1, 2021, at ANO-2 it was discovered that the audible counts for the source range nuclear instrumentation [IG] could not be heard in the control room as required by Technical Specification 3.9.2. ANO-2 Technical Specification 3.9.2 requires that as a minimum, two source range neutron flux monitors shall be operating, each with continuous visual indication in the control room and one with audible indication in the containment and control room during Mode 6, Refueling. The volume for the audible indication in the control room was turned down to a setting that could not be heard in the control room. Prior to entering Mode 6, the audible counts for both the containment building and the control room were verified to be operable.
This event is being reported under 10 CFR 50.73(a)(2)(i)(B) which requires submittal of a Licensee Event Report within 60 days after the discovery for any operation or condition that was prohibited by the plants technical specifications.
SAFETY ASSESSMENT
Failure to comply with the requirements of ANO-2 Technical Specification 3.9.2 did not result in any consequences to the safety of the general public, nuclear safety, industrial safety, or radiological safety. At the time of the event, fuel movement activities had not commenced other than control rod uncoupling, and no activities were in progress that could have challenged the boron concentration of the reactor coolant system (RCS). The safety significance of this event is determined to be low.
EVENT CAUSE(S)
Operations procedures for draining the RCS and refueling shuffle verify audible indication for source range counts is operable in the control room and containment building as required by ANO-2 Technical Specification 3.9.2. The ANO-2 Operations Shutdown Cooling (SDC) Log/Task Checklist however, incorrectly specified a mode of applicability for the audible indication as during fuel movement vice Mode 6. This conflicted with the ANO-2 Technical Specifications. The event cause was determined to be inadequate procedural guidance.
CORRECTIVE ACTIONS
The ANO-2 SDC Log/Task Checklist has been revised to require audible indication to be checked during each shift while in Mode 6.
PREVIOUS SIMILAR EVENTS
None.