ML20027B988
| ML20027B988 | |
| Person / Time | |
|---|---|
| Site: | Beaver Valley |
| Issue date: | 08/04/1980 |
| From: | Lanning W NRC OFFICE FOR ANALYSIS & EVALUATION OF OPERATIONAL DATA (AEOD) |
| To: | NRC OFFICE FOR ANALYSIS & EVALUATION OF OPERATIONAL DATA (AEOD) |
| References | |
| AEOD-E006, AEOD-E6, NUDOCS 8210120120 | |
| Download: ML20027B988 (1) | |
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AUG 4158D AE00/E006 f
This is an internal, pre-f decisional document not fl0TE TO:
File necessarily representing a r
FROM:
Wayne D. Lanning, Office for Anilysis and position of AE0D or NRC.
Evaluation of. Operational Data
SUBJECT:
LOSS OF RN AT EEAVER VALLEY, LER 80-031
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On May 21, 1980, the RHP, system was inoperabTer for approximately five hours..
The plant had been in cold shutdown since Nove=ber 30, 1979. As.a result of a leak in the weld attaching a 3/4" line to the comon header of the RHR pumps, l
_the.. isolation valves to the RHR syste= were re-energized as a precaution in
, case of a gross failure. The valves closed after'tiiey were re-energized due i
to a false high pressure signal due to a de-energized process control signal.
i Plant management then elected to repair the wild leak which accounted for the:
S hour period.
i Investication revealed that the safety significance of the total loss of: RHR was minimal due to the following considerations:
1.
The RRR is not part of the emergency core cooling system.
A separate low pressure decay heat removal system which is safety-related was available.
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2.
Due to the low decay heat power level, an alternate cooling.
- system was not required. The reactor coolant system temperature increased from 900F to only 1150F, during the period.
i Since this leak appeared similar to several I,ERs in RHR systems due to fatigue failure caused by vibration, the Pipe Crack E'
' Group included this issue in its study. A report is to be issued in abon e a ',teeks. Therefore, no further AEOD action is planned.concerning this event. wis type of event will remain on qy watch list for future consideration.
Original signed by, 1Tayne D. T="r 1.
^
.liayne D. Lanning f
Office for Analysis and Evaluation of Operational Data i-cc:
J. Heltemes l
I C. I;ichelson
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I 8210120120 800804 I
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