05000269/LER-2000-003, Regarding Inoperable Emergency Feedwater Flowpath
| ML103570052 | |
| Person / Time | |
|---|---|
| Site: | Oconee  |
| Issue date: | 12/21/2010 |
| From: | Gillespie T Duke Energy Carolinas |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| LER 00-003-00 | |
| Download: ML103570052 (3) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications |
| 2692000003R00 - NRC Website | |
text
Duke T. PRESTON GILLESPIE, Jr.
Vice President tok Energy.
Oconee Nuclear Station Duke Energy ON01 VP / 7800 Rochester Hwy.
Seneca, SC 29672 864-873-4478 864-873-4208 fax December 21, 2010 T. Gillespie@duke-energy. com U.S. Nuclear Regulatory Commission Document Control Desk Washington, D.C. 20555
Subject:
Oconee Nuclear Station Docket Nos. 50-269 Licensee Event Report 269/2010-03, Revision 0 Problem Investigation Process No.: 0-10-8435 Gentlemen:
Pursuant to 10 CFR 50.73 Sections (a)(1) and (d), attached is Licensee Event Report 269/2010-03, Revision 0, regarding a flow path of Emergency Feedwater being inoperable longer than allowed by Technical Specifications.
This report is being submitted in accordance with 10 CFR 50.73 (a)(2)(i)(B). However, a cause investigation into this event is still in progress; therefore, this report is incomplete.
A revision to this report is planned and will be submitted after completion of the cause investigation. There are no other commitments contained in this report.
The expected date of submission.of the revision is February 17, 2011, however that date is not a commitment.
This event is considered to be of no significance with respect to the health and safety of the public.
Any questions regarding the content of this report should be directed to Randy Todd at 864-873-3418.
Sincerely, T. F reston Gillespie, Jr., Vice President Ocownee Nuclear Site Attachment www. duke-energy com
Document Control Desk Date: December 21, 2010 Page 2 cc:
Mr. Luis Reyes Administrator, Region II U.S. Nuclear Regulatory Commission Marquis One Tower 245 Peachtree Center Ave., NE, Suite 1200 Atlanta, GA 30303-1257 Mr. John Stang Project Manager U.S. Nuclear Regulatory Commission Office of Nuclear Reactor Regulation Washington, D.C. 20555 Mr. Andrew Sabisch NRC Senior Resident Inspector Oconee Nuclear Station INPO (Word File via E-mail)
Abstract
On 10/27/2010 at approximately 2358, the "A" Steam Generator Emergency Feedwater Control Valve (1 FDW-315) opened unexpectedly when a test procedure isolated instrument air and auxiliary instrument air to allow stroke testing on the nitrogen (N2) supply only. N2 is the credited pneumatic source.
Initial investigation determined that the nitrogen regulator (1 N-328) for the "B" bottle supply was inadequately set such that the downstream pressure was zero. 1 FDW-315 is designed to fail open upon loss of air/N2, so the valve responded as expected. Operations initially realigned to the "A" supply and exited Technical Specification (TS) 3.7.5 Condition B at 0239 on 10/28/2010. Maintenance reset 1N-328 to the correct pressure setting per procedure on 11/02/2010.
Work history indicated that the regulator had been adjusted during maintenance on 9/5/2010. Thus the potential exists that Unit 1 operated with this train inoperable longer than allowed by TS 3.7.5 Conditions B and D. A cause investigation has been initiated, and this report will be supplemented after it is completed.
This event is considered to have no significance with respect to the health and safety of the public.