05000298/LER-1980-032, Forwards LER 80-032/03L-0

Forwards LER 80-032/03L-0

ML19331E015
Person / Time
Site:	Cooper
Issue date:	08/22/1980
From:	Lessor L NEBRASKA PUBLIC POWER DISTRICT
To:	Seyfrit K NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
Shared Package
ML19331E016	List: 05000298/LER-1980-032, Forwards LER 80-032/03L-0 05000298/LER-1980-032-03, /03L-0:on 800725,during Performance of Surveillance Procedure 6.2.2.2.1,isolation of HPCI Steam Line Occurred.Cause Not Fully Determined.Probable Cause Due to Transient in Common Sensing Line
References
CNSS800518, NUDOCS 8009050199
Download: ML19331E015 (2)

LER-1980-032, Forwards LER 80-032/03L-0

Event date:
Report date:
2981980032R00 - NRC Website

text

COOPER NUCLEAR STATION y{t%

Nebraska Public Power District

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o CNSS800518 August 22, 1980 Mr. K. V. Seyfrit, Director U.S. Nuclear Reg'ilatory Commission Office of Inspection and Enforcement Region IV 611 Ryan Plaza Drive Suite 1000 Arlingtan, Texas 76011

Dear Sir:

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This report is submitted in accordance with Section 6.7.2.B.3 of the Technical Specitications for Cooper Nuclear Station and discusses a reportable occurrence that was discovered on July 25, 1980. A licensee event report form is also enclosed.

Report No.:

50-298-80-32 Report Date:

August 22, 1980 Occurrence Date: July 25, 1980 Facility:

Cooper Nuclear Station Brownville, Nebraska 68321 Identification of Occurrence:

Condition leading to operation in a degraded node permitted by a limiting conditica for operation specified in Technical Specifi-cation 3.5.C.

Conditions Prior to Occurrence:

Reactor power was at approximately 100% of rated thermal power.

Description of Occurrence:

On July 25, 1980, surveillance procedure 6.2.2.2.1, ADS Water Level Functional / Calibration Test, was initiated. The purpose of this surveillance procedure is to perform an instrument calibration and functional test of NBI-LIS-83A and 83B (vessel level)- switches.

After returning NBI-LIS-83A to service, an isolation of the HPCI steam line occurred. The isolation was initiated by a high water level trip from NBI-LIS-101B. The isolation was immediately reset.

QS S,l, 8009050

.S

a Mr. K. V. Seyfrit August 22, 1980 Fage 2.

Designation of Apparent Cause of Occurrence:

The cause of this occurrence is not fully known.

It may have been caused by a transient in the common sensing line introduced by opening the isolation valve prior to the pressurizing valve or by opening the pressurizing valve too quickly.

Analysis of Occurrence:

The remaining high pressure ECCS System (ADS System), the low pressure ECCS Systems (LPCI Subsystem and Core Spray Subsystems),

and the RCIC System were operable during the momentary isolation of the HPCI steam line. The HPCI System isolation was immediately reset and the HPCI System was operable for automatic initiation.

This occurrence presented no adverse consequnnces from the stand-point of public health and safety.

Corrective Action

This occurrence has been reviewed with all Instrument Technicians.

No further action is planned at this time.

Sincerely, L. C. Lessor Station Superintendent Cooper Nuclear Station LCL:cg Attach.