05000328/LER-1996-004, Forwards LER 96-004-01 Which Discusses Details Concerning Replacement of Reactor Trip Breaker B

Forwards LER 96-004-01 Which Discusses Details Concerning Replacement of Reactor Trip Breaker B

ML20137T360
Person / Time
Site:	Sequoyah
Issue date:	03/28/1997
From:	Adney R TENNESSEE VALLEY AUTHORITY
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20137T365	List: 05000328/LER-1996-004, Forwards LER 96-004-01 Which Discusses Details Concerning Replacement of Reactor Trip Breaker B
References
NUDOCS 9704160078
Download: ML20137T360 (2)

LER-2096-004, Forwards LER 96-004-01 Which Discusses Details Concerning Replacement of Reactor Trip Breaker B

Event date:
Report date:
3282096004R00 - NRC Website

text

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Tennessee Valley Authority, Post Offee Box 2000, Soddy-Daisy. Tennessee 37379-2000 R.J. Adney Site Vee President Sequoyah Nuclear Plant 2

March 28,1997 U.S. Nuclear Regulatory Commission i 1

ATTN: Document Control Desk Washington, D.C. 20555 Gentlemen:

4 TENNESSEE VALLEY AUTHORITY - SEQUOYAH NUCLEAR PLANT (SQN) 4 UNIT 2 - DOCKET NO. 50-328 - FACILITY OPERATING LICENSE DPR

• LICENSEE EVENT REPORT (LER) 50-328/96004, REVISION 1 The enclosed LER revision provides details concerning the replacement of reactor trip i

breaker "B". After the replacement breaker was removed from service, it was found to have  ;

a problem with the linkage for the auxiliary contacts. This caused two of the three relays of the auxiliary contacts to be inoperable. This resulted in a failure to comply with the

, technical specification (TS) requirements pertaining to the auxiliary contacts for reactor trip breaker "B" When the original report was submitted, the root cause had not been established. The root cause has now been established and the results are being transmitted

, in this revision to the original report. This revision supersedes the original report. In ,

I addition, investigation revealed on February 3,1997, that the redundant reactor trip breaker '

i "A" had missed one portion ofits required surveillance and was not technically operable in  ;

accordance with TSs during the time breaker "B" was not operable. This condition was not related to the linkage problems which existed on breaker "B". Subsequent testing has proven i the "A" breaker was fully functional. This information was not available during the December 16,1996, enforcement conference, but was provided to the Region II staff on February 3 and 4,1997, and to the acting regional administrator, Jon Johnson, on  !

February 5,1997.

The event was originally reported on October 23,1996, in accordance with 10 CFR 50.73(a)(2)(i)(B) as an operation prohibited by the plant TSs.

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R. J. Adney Enclosure (See page 2) 9704160078 970328

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U.S. Nuclear Regulatory Commission Page 2 March 28,1997 Enclosure cc (Enclosure):

Mr. R. W. Hernan, Project Manager U.S. Nuclear Regulatory Commission One White Flint, North  :

11555 Rockville Pike Rockville, Maryland 20852-2739 l i

INPO Records Center.

. Institute of Nuclear Power Operations )

700 Galleria Parkway Atlanta, Georgia 30339-5957 9

NRC Resident Inspector Sequoyah Nuclear Plant 2600 Igou Ferry Road Soddy-Daisy, Tennessee 37379-3624 Regional Administrator U.S. Nuclear Regulatory Commission .

Region II-101 Marietta Street, NW, Suite 2900 Atlanta, Georgia 30323-2711 i

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