ML20045H417

Special Rept:On 930608,fire Detection for Containment 11A & 11B Reactor Coolant Pump Motor Bay Disabled to Prevent Spurious Trouble Alarms & Not Restored within 14 Days. Caused by High Temps in Bays.Temp Monitored Once Per Hour

ML20045H417
Person / Time
Site:	Calvert Cliffs
Issue date:	07/09/1993
From:	Cruse C BALTIMORE GAS & ELECTRIC CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
NUDOCS 9307200188
Download: ML20045H417 (2)

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BALTIMORE .

, GAS AND i ELECTRIC CALVERT CLIFFS NUCLEAR POWER PLANT ,

1650 CALVERT CLIFFS PARKWAY

• LUSBY. MARYLAND 20657-4702 CHARLES H CRUSE July 9,1993 PLANT GENERAL MANAGER -

CALVERT CLIFF S '!

U. S. Nuclear Regulatory Commission Washington, DC 20555 ATTENTION: Document Control Desk

SUBJECT:

Calvert Cliffs Nuclear Power Plant Unit No.1; Docket No. 50-317 Fire Detection Instrumentation Special Report Technical Specification 33.3.7. ACTION Statement b Per the requir: cc 7ts of Technical Specification 33.3.7, ACTION Statement b, we hereby submit the attached Special Report concerning inoperable fire detection. Specifically the detection system in the Unit 1 Containment 11 A and 11B reactor coolant pump motor bay was inoperable for greater than 14 days.

F Should you have any further questions regarding this matter, we will be pleased to discuss them with you.

Very truly yours, o

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Attachment cc: D. A. Brune, Esquire J. E. Silberg, Esquire R. A. Capra, NRC D. G. Mcdonald, Jr., NRC T. T. Martin, NRC P. R. Wilson, NRC R. I. McLean, DNR J. II. Walter, PSC 9307200188 930709  :

PDR- ADOCK 05000317 PDR h* k 5 f  :

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, KtTACIINf ENT (1)

FIRE DETECTION INSTRUNiENTATION SPECIAL REPORT HACKGROUND On June 8,1993 the fire detection for the Unit 1 Containment No.11A and 11B reactor coolant pump motor bay was disabled. The heat detection in 11A and 11B reactor coolant pump motor bay was disabled to prevent spurious trouble alarms. The heat detection could not be restored within the -

14 days required by the Technical Specification 3.3.3.7.b.

Actions were taken to determine the cause of the alarm on June 8,1993. It was concluded that there  !

was not a fire initiating the alarm but unusually high temperatures in the containment causing the spurious alarm. This condition results in a hanging alarm at the fire alarm panel (1C24B) in the Control Room. To allow other plant alarms to be received and annunciate at the fire alarm panel, a temporary alteration was installed to disable the heat detection circuit.

As specified by Technical Specification 3.3.3.7 ACTION Statement b, a special report must be submitted pursuant to Technical Specification 6.9.2 if the detection system is not restored within 14 days.

EFFECT ON UNIT OPERATIONS On June 8,1993 with Unit 1 at 100 percent power, the heat detection system was disabled in the 11 A and 11B reactor coolant pump motor bay via a temporary alteration. The heat detection in this area is listed in Technical Specification Table 3.3.11 and is addressed by Technical Specification 3.3.3.7.

In accordance with Technical Specification 3.3.3.7, ACTION Statement a, the containraent air temperature is being monitored once per hour at the locations listed in Technical Specification 4.6.1.5.

PLANS ANDyCIIEDULES An engineering evaluation is being conducted to identify the cause of the unusually high temperatures in the RCP bays and corrective actions will be taken during the next unit shutdown if required. The heat detection will remain disabled and appropriate action will continue in accordance with Technical Specification Requirements until the heat detection is restored to an operable status.

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