ML20101D220

Ro:On 920603,control Room Alarms Annunicated Loss of One of Two Compressors in Train a of Control Room HVAC Sys.Caused by Low Oil Pressure in Compressor.Both Trains of Control Room HVAC Sys Restored to Svc & Declared Operable

ML20101D220
Person / Time
Site:	Comanche Peak
Issue date:	06/04/1992
From:	William Cahill, Walker R TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC)
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
TXX-92278, NUDOCS 9206120063
Download: ML20101D220 (2)

Text

_g. 3 s

hmS Log # TXX-92278 File # 10013 10125 Ref. # 10CFR50.72(a)(i)

TUELECTRIC William J. Cah!!!, Jr.

Group Vke Preskkno V. S. Nuclear Regulatory Commiss_ ion Attn: Document Control Desk Washington, DC 20555

SUBJECT:

COMANCHE PEAK STEAM ELECTRIC STATION (CPSES)

DOCKET NOS. 50-445 AND 50-446 TRANSMITTAL OF REPORT FOLLOWING A NOTIFICATION OF UNUSUAL EVENT (NUREG-0654)

Gentlemen:

As specified in the CPSES Emergency Plan, TV Electric hereby transmits the enclosed report which summarizes the incident which occurred on June 3, 1992.

As stated-in the corrective action, an evaluation is in process and a Licensee Event Report (LER) will be submitted in-accordance with 10CFR50.73 by July _6,'1992.

Sincerely, k'

3h, William J. Cahill, Jr.

By:

Yi Roger D. Walker Manager of Regulatory Affairs 08/ds Enclosure c - (ir. R. D. Martin, Region IV Resident Inspectors, CPSES (2)

Mr. Robert Lansford, Division of Emergency Management Mr. B.-E. Holian, NRR Mr. T. A.' Bergman, NRR 1C0Cd2

$8 9206120063 920604 i[

ADOCK 0500 5

{DR P.o. Box 1002 Glen Rose.Texa. 7&M3-1002

/,f.

Enclosuria TXX-92278' Pag'e 1 of 1' TU Electric Comanche Peak Steam Electric Station, Unit 1 Docket No. 50-445 Notification of Unusual Event As a Result of Initiating a Plant Shutdown Required by Technical Specifications Recort Requirement This report is being submitted as recommended by NUREG-0654, " Criteria for Preparation and Evaluation of Radiological Emergency Response Plans and Preparedness-in Support of Nuclear. Power - Plants" and in accordance with Comanche Peak Steam Electric Station (CPSES) Emergency Plan Procedures.

The CPSES Emergency Pian procedures require that a written summary be submitted within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> of the closecut of the Notification of Unusual Event (NOUE).

Event Description On June 3,

1992, at approximately 0123 CDT, CPSES Unit I was in Mode 1,

Power Operation,.with the reactor at approximately 100 percent of rated thermal power.

Control Room alarms annunciated the loss of one of two compressors associated ~with

, Train A of the Control Room Heating Ventilation and Air Conditioning (HVAC) System.

After unsuccessfully attempting to restart the compressor, the train was declared inoperable.

Train B.of the Control Room HVAC System had been removed from service and declared inoperable. previously for performance of a modification to reduce vibration.

The' loss of both trains of Control Room HVAC resulted in the requirement to initiate a plant shutdown in accordance with CPSES Unit 1 Technical Specification 3.0,3.

-At approxinately 0223 CDT, a plant shutdown was initiated, and at 0250 the Emergency Plan was activated with the Notification of Unusual Event.

The Nuclear Regulatory Commission and the appropriate offsite agencies were notified in accordance with the applicable regulatory and procedural requirements.

By-0823 CDT, Train A of,the Control Room HVAC System had been restored to service and--the - NOUE ? was -terminated.

Reactor power had been reduced to approximately 8 percent. = Initial review of the event indicates that all Technical Specification action requirements were satisfied, and all systems functioned as designed.

'Immediate cause The -immediate cause of the Control Room HVAC air conditivning unit trip has been attributed to compressor low oil pressure.

' Corrective Actions

~Immediate' actions were taken to troubleshoot the cause of the air conditioning unit trip and to place the plant in a condition allowed by the CPSES Unit 1 Technical Specifications.

As a result of subsequent actions, both trains of the Control Room HVAC System were restored to service and declared operable. Additional actions will be determined based on the results of the findings of the plant incident investigation of this event.

The details of the event, including root cause determination and recommendations for corrective actions, will be included in the Licensee Event - Report to be submitted to the Maclear Regulatory Commission pursuant to 10CFR50.73.

I