ML20134M456

Corrected Page 4 to Insp Repts 50-295/85-22 & 50-304/85-23, Correcting Paragraph 2 Re Westinghouse Analysis of DNBR Margins

ML20134M456
Person / Time
Site:	Zion  File:ZionSolutions icon.png
Issue date:	08/30/1985
From:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
To:
Shared Package
ML20134M454	List: ML20134M452 ML20134M456
References
50-295-85-22, 50-304-85-23, NUDOCS 8509040131
Download: ML20134M456 (1)

See also: IR 05000295/1985022

Text

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NRR provided the requested assistance and documented the effort in

a Safety Evaluation Report (SER) issued June 27, 1985. The SER

addressed each of the above issues and concluded that Commonwealth

Edison's treatment of these issues was acceptable. NRR also points

out that should the situation occur again a new and current analysis

should be performed for the new occurrence. The inspector has

reviewed the Safety Evaluation Report and concurs with its conclusions.

The licensee's efforts to identify and correct the cause of 2

temperature deviation have been unsuccessful to date. The '.icensee has

therefore obtained an analysis from Westinghouse which concludes that

the available Departure from Nucleate Boiling Ratio margins for the

previous cycle (8) were unchanged by the reload and that operation in

Cycle 9 with this condition is permissible. An onsite review of the

Westinghouse analysis was conducted on June 12, 1985. The inspector

has no additional questions at this time.

No violations or deviations were identified.

3. Sumary of Operations

,

Unit 1

Unit 1 operated at full power levels throughout the inspection period.

Unit 2

Unit 2 operated at power levels as high as 93% at the beginning of the

inspection period and is currently in coastdown in preparation for a

refueling outage.

At 6:25 a.m. on July 18, 1985, the licensee declared the 2B diesel

generator (DG) inoperable after it had tripped on an overspeed condition

thereby placing the unit in a four hour action requirement to be in hot

shutdown as required by Technical Specifications. An Unusual Event was

declared at this time.

Prior to the 2B DG tripping, the 2B Residual Heat Removal (RHR) pump

had been taken out of service.for replacement of the lower motor bearing.

Technical Specification 4.8.3.C requires that when one of the two RHR

pump systems is inoperable the remaining RHR system, both centrifugal

charging pumps and safety injection pumps and associated standby AC and

DC power supplies, be demonstrated to be operable imediately and daily

thereafter. Technical Specifications states further that if the

conditions cannot be met, the reactor shall be brought to hot shutdown

in four hours.

At 7:46 a.m., July 18,1985, the 2B DG was declared operable after

successful completion of a surveillance test and the Unusual Event was

terminated.

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