ML20082S033

Revised Monthly Operating Rept for June 1991 for Fort Calhoun Station Unit 1

ML20082S033
Person / Time
Site:	Fort Calhoun
Issue date:	06/30/1991
From:	OMAHA PUBLIC POWER DISTRICT
To:
Shared Package
ML20082S030	List: ML20082S027 ML20082S033
References
NUDOCS 9109170004
Download: ML20082S033 (1)

Text

-OMAHA PUBLIC P0WER DISTDICT Fort Calhoun Station Unit No.1 June 1991 Monthly Operating Report I. OPERATIONS

SUMMARY

Fort Calhoun Station operated at 75% power until June 16, 1991, when /

power was raised to 98% to meet seasonal demand. On June 19, 1991, /

power was reduced to 55% for repair of condenser waterbox valves. /

Following repairs to these valves on June 20, 1991, a power increase /

to 100% was initiated. /

/

On June 20, 1991, a gas pressure switch for house service transformer /

TIA-4 was tripped due to technician error, locking out 161KV offsite /

power. The transfer to the 345KV system occurred without incident. /

After investigation of the cause, th' switch was reset and 161KV power /

was restored. /

/

During June 1991, a hot weather test was performed on emergency diesel /

l generator DG-1, The test results in conjunction with a detailed /

l system analysis were used to support raising the ambient temperature /

operating limits on emergency diesel generators DG-1 and DG-2 to- /

110*F. /

/

The fol'owing NRC Inspections took place in June 1991: /

/

IR 91-09 Corrective Action /

IR 91-16 Resident's Periodic Inspection /

IR 91-17 Radiation Protection /

IR 91-18 Security /

/

The following LERs were submitted: /

/

-LER-91-04 R1 Offsite Power low Signal Outside Design Br 's /

/

A. SAFETY VALVES OR PORV CHALLENGES OR FAILURES WHICH OCCURRED? /

/

None /

B. RESULTS OF LEAK RATE TESTS The results of the reactor coolant leak rate tests for June 1991, indicate the the reactor coolant system (RCS) and chemical and volume control system (CVCS) are both relatively leak tight. Total RCS leakage averaged about 0.12 gpm during June.

The maximum leak rate for the month was recorded on June 20, 1991 when the total leak rate was 1.824 gpm and the unknown leak rate was 1.757 gpm. -The total leak rate dropped to 0.012 gpm and the unknown leak rate dropped to -0.054 gpm when the test was repeated. The plant was undergoing power changes on June 20, 1991 which are believed to have affected leak rate test accuracy, i

9109170004 91o913 Revision 1, September 6, 1991

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