05000373/LER-1982-034, Forwards LER 82-034/03L-0.Detailed Event Analysis Encl

From kanterella
(Redirected from 05000373/LER-1982-034)
Jump to navigation Jump to search
Forwards LER 82-034/03L-0.Detailed Event Analysis Encl
ML20054L150
Person / Time
Site: LaSalle Constellation icon.png
Issue date: 06/23/1982
From: Holyoak R
COMMONWEALTH EDISON CO.
To: James Keppler
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
Shared Package
ML20054L151 List:
References
NUDOCS 8207070194
Download: ML20054L150 (2)


LER-2082-034, Forwards LER 82-034/03L-0.Detailed Event Analysis Encl
Event date:
Report date:
3732082034R00 - NRC Website

text

. , - . . - ___ -. __

.' O s Commonwitith Edison e LaSalle County Nuclear Station m

) Rural Route #1, Box 220 v Marseilles, Illinois 61341 s Telephone 815/357 6761 I

i June 23, 1982 James G. Keppler Regional Administrator Directorate of Regulatory Operations, Region lil U. S. Nuclear Regulatory Commission 799 Roosevelt Road Glen Ellyn, IL 60137

Dear Si r:

Reportable Occurrence Report #82-034/03L-0 Docket #050-373 is being 3

submitted to your office in accordance with LaSalle County Nuclear Power Station Technical Specification 6.6.B.2. (c), observed inade-quacies in the implementation of administrative or procedural controls which threaten to cause reduction of degree of redundancy provided in 1

reactor protection systems or engineered safety feature systems.

l

<u R. H. Holy kt ,

I superintendent N

)

LaSalle County ation ]

RHH/GW/djp Enclosure cc: Director of Inspection & Enforcement Director of Management Information & Program Control U. S. NRC Document Management Branch inpo-Records Center File /NRC l

I207070194 820623

{DRADOCK 05000373 g30 M

4

1. LER NUMBER: 82-034/03L-0
11. LA SALLE COUNTY STATION: UNIT 1 111. DOCKET NUMBER: 050-373 IV. EVENT DESCRIPTION:

The RHR System was being lined up for the shutdown cooling mode of operat1~on per LOP-RH-07 The RHR Shutdown Cooling Suction Header isolation Valve (IE12-F009) would not open. Subsequent investigation found RHR Pump Suction flow switch 1E31-N0128 isolated.

V. PROBABLE CONSEQUENCES OF THE OCCURRENCE The plant was in Condi tion 3, Hot Shutdown, at approximately 225 F reactor coolant temperature. Tech. Spec. 3 3 2. requires one channel per trip system to be operable. A redundant channel from RHR pump suction flow switch 1E31-N012A was operable. Technical Specification 3.4.9.1 requires that shutdown cooling flow be established as soon as possible. The RWCU non-regenerative heat exchanger was operable and in service for heat removal.

There is no irradiated fuel generating decay heat at this time. Safe .

operation of the plant was maintained at all times.

VI. CAUSE:

l The last documentated operation the RHR pump suction flow switch IE31-N012B was on 6/5/82, the date of the Deviation Report. The Instrument Maintenance Department was performing LIS-RH-12 (RHR, Shutdown Cooling Mode, High Suction

~1 flow isolation and Functional Test). The Instrument Mechanic contacted related he cut the lockwires on RHR pump suction flow switch 1E31-N012B, isolated the instrument, repaired a leak on the manifold block, completed the Inst. Calibra tion Check, then went on break. After break he was reassigned to a higher priority job. It can not be determined with certainty the status (inservice or isolated) of instrument 1E31-N012B when the instrument mechanic

was reassigned.

Vll. CORRECTIVE ACTION:

i l

RHR pump suction flow switch 1E31-N012B was immediately unisolated and returned to service. Shutdown cooling was established'dithin one hour.

AIR 1-82-312 has beer. issued to the Instrument Maintenance Department to re-emphasis the importance of LAP-24E1, step f.6. This item refers to informing the shif t engineer of system status if a test is stopped or delayed.

Prepared by: A. C. Settles

. .-. - . . _ . -_ . - - - - -