ML20039D310

Forwards LER 81-023/01T-0.Detailed Event Analysis Encl

ML20039D310
Person / Time
Site:	Oconee
Issue date:	12/23/1981
From:	Parker W DUKE POWER CO.
To:	James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
Shared Package
ML20039D311	List: ML20039D310 ML20039D317
References
NUDOCS 8112310514
Download: ML20039D310 (2)

Text

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O Dunn POWER COMPANY '

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Powen lluutnixo 402 Sourn Curucu STREET, CRAHIDTTE, N. C. cana W I LLI AM O. PA R M E R, J R.

31 DEC 28 A9: 50 Vicr PRE 5iDENT TELEPMcNE A#ta 704 STra.e PRoovcnow 373-4083 December 23, 1981 0 to O

Mr. James P. O'Reilly, Director U. S. Nuclear Regulatory Commission

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Region II 101 Marietta Street, Suite 3100 _{j

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Re: Oconee Nuclear Station 'A Docket No. 50-269 b,.

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Dear Mr. O'Reilly:

Please find attached Reportable Occurrence Report R0-270/81-23. This report is submitted pursuant to Oconee Nuclear Station Technical Specification 6.6.2.1.a(9), which concerns the discovery of conditions not specifically considered in the safety analysis report or Technical Specifications that require corrective measures to prevent the existence or development of an unsafe condition, and describes an incident which is considered to be of no significance with respect to its affect on the health and safety of the public.

Ve y truly yours,

_ e./ x .

William O. Parker, J JLJ/php Attachment ec: Director Records Center Office of Management & Program Analysis Institute of Nuclear Power Operations U. S. Nuclear Regulatory Commission 1820 Water Place Washington, D. C. 20555 Atlanta, Georgia 30339 Mr. W. T. Orders NRC Resident Inspector Oconee Nuclear Station

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DUKE POWER COMPANY OCONEE UNIT 1 Report Number: R0-269/81-23 Report Date: December 23, 1981 Occurrence Date: December 9, 1981 Facility: Oconee Unit 1, Seneca, South Carolina Identification of Occurrence: Control cables to valve lHP-26 do not meet separation criteria.

Conditions Prior to Occurrence: Cold Shutdown Description of Occurrence: On November 25, 1981 four gray safety-related i cables which did not meet channel separation criteria were discovered in the Unit 1 cable shaft. The cables were installed adjacent to yellow safety-related cables during original plant construction. It was subsequerstly determined that all four cables were control cables for valve lHP-26 (HPI Loop A Injection Inlets). It was determined that this incident was a reportable occurrence at 1535 on December 9, 1981.

Apparent Cause of Occurrence: This incident was the result of improper-original field installation of the four gray cables'and several yellow cables.

Analysis of Occurrence: Separation of electrical cabling for redundant channels is a requirement of electrical drawing OEE-14 and is assumed in the FSAR. ' It is also a standard installation practice to physically separate redundant safety cables as much as possible. These criteria were violated when the gray and yellow cables were installed, thus creating a potential for an unsafe condition. ~Since the cables were not physically separated, the potential existed for an electrical fault in one safety. channel to cause an electrical:

fault in a redundant channel. This violctes'the single failure criteria of safety systems. Based on the f act that no failure occurred, it is con-sidered that the health and safety of the public were not affected.

Corrective Action: The four gray safety-related cables were pulled back'to the location of the cross-channeling and properly reinstalled.

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