05000369/LER-2005-001, Re Reactor Coolant System Leakage Detection Instrumentation Inoperable
| ML051310167 | |
| Person / Time | |
|---|---|
| Site: | McGuire, Mcguire  |
| Issue date: | 05/02/2005 |
| From: | Gordon Peterson Duke Power Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| LER 05-001-00 | |
| Download: ML051310167 (8) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications |
| 3692005001R00 - NRC Website | |
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Duke GARY R. PETERSON r Powero Vice President McGuire Nuclear Station A Duke Energy Company Duke Power MG01 VP / 12700 Hagers Ferry Rd.
Huntersville, NC 28078-9340 704 875 5333 704 875 4809 fax grpeters @duke-energy. corn May 2, 2005 U.S. Nuclear Regulatory Commission Document Control Desk Washington, D.C.
20555
Subject:
McGuire Nuclear Station, Unit 1 and Unit 2 Docket No. 50-369, 50-370 Licensee Event Report 369/2005-01, Revision 0 Pursuant to 10 CFR 50.73, Sections (a)(1) and (d), attached is Licensee Event Report (LER) 369/2005-01, Revision 0.
On March 2, 2005, McGuire Nuclear Station identified past instances where, with regard to the Reactor Coolant System leakage detection function, both Unit's EMF38L and EMF39L Containment Atmosphere Radiation Monitors were inoperable for a period longer than permitted by plant Technical Specifications.
These instances represented an operation prohibited by Technical Specifications reportable as per the requirements of 10 CFR 50.73 (a)(2)(i)(B).
A qualitative risk assessment has determined this event to be of no significance to the health and safety of the public.
There are no regulatory commitments contained in this LER.
. R. Peterson Attachment Xea www. dukepower. corn
U. S. Nuclear Regulatory Commission May 2, 2005 Page 2 of 2 cc:
W. D. Travers U. S. Nuclear Regulatory Commission Regional Administrator, Region II Atlanta Federal Center 61 Forsyth St., SW, Suite 23T85 Atlanta, GA 30303 J. J. Shea (Addressee Only)
NRC Project Manager (McGuire)
U. S. Nuclear Regulatory Commission Mail Stop 0-7 D11 Washington, DC 20555-0001 J. B. Brady Senior Resident Inspector U. S. Nuclear Regulatory Commission McGuire Nuclear Site Beverly 0. Hall, Section Chief Radiation Protection Section 1645 Mail Service Center Raleigh, NC 27699-1645
Abstract
Unit Status: At the time of the event, Unit 1 and Unit 2 were in MODE 1 (Power Operation) at 100 percent power.
Event Description
On December 15, 2004, an initial evaluation of the adequacy of the radioactivity detection sensitivities of both Unit's Containment Atmosphere Particulate Radioactivity Monitor (EMF38L) and both Unit's Containment Atmosphere Gaseous Radioactivity Monitor (EMF39L) concluded these EMFs were operable. However, on March 2, 2005, McGuire concluded the sensitivities of these EMFs were inadequate for them to perform their intended function of detecting a one gallon per minute leak from the Reactor Coolant System within one hour.
In consequence, with regard to the Reactor Coolant System leakage detection function, these monitors were inoperable for periods in excess of Technical Specification requirements.
These instances represented a Technical Specification prohibited operation reportable under the requirements of 10 CFR 50.73 (a)(2)(i)(B).
A risk assessment has determined this event to be of no significance to the health and safety of the public.
Event Cause
The initial evaluation of EMF38L and EMF39L did not recognize that, even though their sensitivities appeared to comply with original licensing basis requirements, current Reactor Coolant System radioactivity levels precluded EMF38L and EMF39L from satisfying their intended function of detecting a one gallon per minute Reactor Coolant System leak within one hour.
Corrective Action
Additional training will be conducted related to what is to be addressed when evaluating the capability of a structure, system, or component to perform its specified function(s).
License Amendment Request will be submitted clarifying the capabilities of the RCS leakage detection instrumentation.
NRC FORM 366 (6-2004)
(If more space is required, use additional copies of (If more space is required, use additional copies of (If more space is required, use additional copies of (If more space is required, use additional copies of (It more space is required, use additional copies of NRC Form 366A)
Given the redundant RCS leakage detection methods and the absence of significant Unit 1 and Unit 2 RCS leakage, the risk associated with the event was negligible.
Therefore, the event described in this LER was not significant with respect to the health and safety of the public.
ADDITIONAL INFORMATION
A review of the McGuire corrective action database identified a 1994 event related to the inability of both Unit's EMF38L and EMF39L to detect a one gallon per minute leak from the RCS within one hour (reference LER 369/94-02).
However, the circumstances, cause, and corrective actions associated with that event are sufficiently different such that the event described in this LER is not considered a recurring event.
Applicable Energy Industry Identification (EIIS) system and component codes are enclosed within brackets.
McGuire unique system and component identifiers are contained within parentheses.