NLS2015063, Retraction of Licensee Event Report 2014-005-00, Lube Oil Leak Results in a Potential Condition Prohibited by Technical Specifications and a Potential Loss of Safety Function.

Retraction of Licensee Event Report 2014-005-00, Lube Oil Leak Results in a Potential Condition Prohibited by Technical Specifications and a Potential Loss of Safety Function.

ML15167A067
Person / Time
Site:	Cooper
Issue date:	06/09/2015
From:	Limpias O Nebraska Public Power District (NPPD)
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
LER 14-005-00, NLS2015063
Download: ML15167A067 (2)

Text

N Nebraska Public Power District Always there when you need us 50.73 NLS2015063 June 9, 2015 U.S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, D.C. 20555-0001

Subject:

Retraction of Licensee Event Report 2014-005-00, "Lube Oil Leak Results in a Potential Condition Prohibited by Technical Specifications and a Potential Loss of Safety Function" Cooper Nuclear Station, Docket No. 50-298, License No. DPR-46

Reference:

Letter from Oscar A. Limpias, Nebraska Public Power District, to U.S. Nuclear Regulatory Commission dated December 10, 2014, "Licensee Event Report 2014-005-00" (NLS2014099) (ML14350A214)

Dear Sir or Madam:

The purpose of this letter is for the Nebraska Public Power District to retract Licensee Event Report (LER) 2014-005-00 submitted per the Reference letter. The LER was submitted in accordance with 10 CFR 50.73, "Licensee Event Report System," paragraph (a)(2)(i)(B), as a potential condition prohibited by Technical Specifications, and paragraph (a)(2)(v)(D), a potential loss of safety function.

The basis for reportability as described in LER 2014-005-00 was an October 13, 2014. event where a lubricating oil leak was observed on the #2 Diesel Generator (DG) during performance of an operability test. The right bank camshaft thrust bearing cover bolting was found loose, with some missing. This condition could potentially affect the ability of the DG to perform its safety function for the required mission time.

Cooper Nuclear Station was in Mode 5 conducting a refueling outage at the time the condition was identified. An Event Notification was not required because the DG was not required to be operable during Mode 5 with the redundant DG operable. While this condition was being evaluated, LER 2014-005-00 was submitted in accordance with 10 CFR 50.73(a)(2)(i)(B) and (a)(2)(v)(D), with the expectation that a supplement to the report would be submitted following completion of the evaluation.

The results of the evaluation concluded the factors causing the lubricating oil leak occurred during the DG maintenance window. Prior to the maintenance window being conducted during the refueling outage, the DG would have been able to perform its safety function for the required COOPER NUCLEAR STATION P.O. Box 98 / Brownville, NE 68321-0098 Telephone: (402) 825-3811 / Fax: (402) 825-5211 www.nppd.com

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NLS2015063 Page 2 of 2 mission time. Therefore, the event is not reportable under 10 CFR 50.73 and LER 2014-005-00 is being retracted.

No formal licensee commitments are being made in this correspondence.

Should you have any question concerning this matter, please contact Jim Shaw, Licensing Manager, at (402) 825-2788.

Since ely, cA. Limpias Vice President - uclear and Chief Nuclear Officer

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