05000312/LER-1981-019, Forwards LER 81-019/03L-0 & Submits Detailed Event Analysis

Forwards LER 81-019/03L-0 & Submits Detailed Event Analysis

ML20003F787
Person / Time
Site:	Rancho Seco
Issue date:	04/15/1981
From:	Mattimoe J SACRAMENTO MUNICIPAL UTILITY DISTRICT
To:	Engelken R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
Shared Package
ML20003F788	List: 05000312/LER-1981-019, Forwards LER 81-019/03L-0 & Submits Detailed Event Analysis 05000312/LER-1981-019-03, /03L-0:on 810316,obstruction in Suction of Atmosphere Radiation Monitor R15001B Discovered.Caused by Plastic Cap from Bottle of Industrial Leak Detection Fluid. Bottle Cap Removed from Sample Line Suction
References
NUDOCS 8104230595
Download: ML20003F787 (2)

LER-1981-019, Forwards LER 81-019/03L-0 & Submits Detailed Event Analysis

Event date:
Report date:
3121981019R00 - NRC Website

text

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SACRAMENTO MUNICIPAL UTILITY DISTRICT C 6201 S Street. Box 15830. Sacramento. California 95813; (916) 452 3211 Aprii 15, 1981 9e /

'o"\\1 R. H. ENGELKEN, DIRECTOR V

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REGION V 0FFICE OF INSPECTION & ENFORCEMENT U. S. NUCLEAR REGULATORY COMMISSION

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REPORTABLE OCCURRENCE 81-19 in accordance with Technical Speci fications for Rancho Seco Nuclear Generating Station, Section 6.9.4.2(b) and Regulatory Guide 1.16, Revision 4, Section C.2.b(3),.the Sacramento Municipal Utility District is hereby submitting a thirty-day report of Reportable Occurrence 81-19 On March 16, 1981, while conducting sampling tests to determine whether the reactor building atmosphere radiation monitor, RiS001B, was measuring activity representative of the building atmosphere, an obstruction was found in the suction of the monit'.ar's sample line. The obstruction was TM a plastic cap from a bottle of SN00P

, an industrial leak detection fluid f requently utilized during maintenance evolutions at Rancho Seco.

The bottle cap was removed from the sample line suction.

Discussions with personnel who had worked in the vicinity of the-suction line on the previous day revealed that the line had been observed to be free of any obstructions at that time. As a result it was determined that the maximum time span that the suction line was obstructed was approximately 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

During review of this occurrence by the Plant Review Committee it was determined that obstruction of the suction line of this particular monitor could have resulted in a degradatic. of the post accident emergency sampling system.

To preclude the possibility of such an occurrence being undetected and commencing power operation in the degraded mode, corrective action will be implemented.

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R. H. Engelken April 15, 1981 Prior to returning to power,following the present refueling shutdown, the suction line will be verified to.be free of any obstructions. This will be done during the Reactor Building walk-around inspection, just prior to closing the building.. Additionally, District engineers are evaluating the-feasibility of adding some type of "non pluggable". pipe end to the suction piping of this particular monitor.

If such a modifi-cation is determined feasable, implementation thereof would be pursued during a future outage.

There were no plant transients nor power reductions associated with this e. ant.

s ohn. Mattimoe Assistant General Manager nd Chief Engineer cc:

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