ML20197K118

Submits Daily Highlight.On 850721,reactor Tripped Due to Turbine Trip & on 850721 & 22,auxiliary Feedwater Pumps Autostarted Due to lo-lo Steam Generator Level & High Level, Respectively.Cooldown Effected on 850722 for Valve Repairs

ML20197K118
Person / Time
Site:	Turkey Point
Issue date:	07/23/1985
From:	Tam P Office of Nuclear Reactor Regulation
To:	Harold Denton NRC
Shared Package
ML20197K090	List: IA-85-729, Further Response to FOIA Request for NRC Insp Rept & Related Records Re Evaluation of Auxiliary Feedwater Sys.Documents Listed on Encl App Available in Pdr.Search for Addl Document Continuing ML20197K085 ML20197K118 ML20198A364 ML20198A368 ML20198A371 ML20203H152
References
FOIA-85-729 NUDOCS 8508080205
Download: ML20197K118 (1)

Text

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1. jw 4 - ' UNITED STATES iJ

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kE NUCLEAR REGULATORY COMMISSION WASHINGTON, D. C. 20555

% 8 July 23, 1985 J

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Docket Nos. 50-250 and 50-251 f MEMORANDUM FOR: H. Denton R. Bernero .

D. Eisenhut J. Knight G. Edison W. Russell H. Thompson B. Snyder F. Miraglia T. Speis G. Lainas g7 G..Holahan m a D. Crutchfield D. Vassallo T. Novak J. Miller J. Stolz

"- THRU: Steven A. Varga, Chief' Operating Reactors Branch 1

, Division of Licensing FROM: Peter S. Tam, Project Manager Operating Reactors Branch #1 Division of Licensing 3

SUBJECT:

' DAILY HIGHLIGHT - TURX Y POINT UNIT While operating at a nominal 100% power on u y 21, 1985, the reactor j tripped at 11:41 p.m. due to turbine trip. The exact cause is unknown but a lightning strike occurred in the area at that time.

Approximately one hour later, all three (A, B & C) auxiliary feedwater (AFW) pumps auto-started due to low-low level in steam generator 3B. The low-low level was caused by failure of the nonnal feedwater train bypass valve to open when demanded by the operator. Auxiliary feedwater pumps A &

C tripped on mechanical overspeed (cause of oversr.eed to be determined).

The B pump was able to maintain water level. Within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />, the A,C pumps were successfully tested and considered operable.

At 4:00 a.m. on 7/22/85 (plant in hot shutdown), all three AFW pumps successfully auto-started due to main feedwater pump trip caused by high level in the 3C steam generator. The level increase was caused by a closed but leaking FW bypass regulating valve. t At 6:04 a.m. on 7/22/85, plant cooldown from hot shutdown to cold shutdown was effected due to required repair of an AFW control valve. This action removes one train of AFW from service to steam generator 3C, resulting in the required cold shutdown. Cause of the failure of the AFW control valve is to be determined.

All information is based on conversations with licensee personnel, the Resident Inspector and ORAB personnel.

I 2

eter S. Tam, Project Manager Operating Reactors Branch #1

,- g569## $ AN oivision of Licensin9 F/7 l