ML19310A219
| ML19310A219 | |
| Person / Time | |
|---|---|
| Issue date: | 06/03/1980 |
| From: | Israel S NRC - TMI-2 BULLETINS & ORDERS TASK FORCE |
| To: | Ross D NRC - TMI-2 BULLETINS & ORDERS TASK FORCE |
| References | |
| IEB-79-05B, IEB-79-5B, NUDOCS 8006060300 | |
| Download: ML19310A219 (2) | |
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7 BIE'iORA::DO: FOh D. F. Eoss, Director, 360 Task Force, : R".
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S. L. Israel, Group Leader, Systems Group, D&O Task Force,';ER
SUBJECT:
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> ' ~ ~a weHMW 29 The events at TMI-2 led the ::RC staff to issue Bulletin 79-053, April 21, 1979, to all operatin:; 36W NSSS licensees requesting them to consider modifying their pressuri: er PORV lif t setpoint and their high pressure reactor clip setpoint in order to minimize the number of PORV cpenings.
Subsequent to this, the licensees increased their PORV setpoints and decreased their high pressure reactor trip setpoint.
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a Tne long-term effect of these setpoint modifications is still unclear, but
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observation and the true long-term effect of these modifications may not be known for some time.
and the setpoint changes, B&W reported experiencing abcut W,. s ef e.
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gj These records supplied by B&W only report cases where a reactor trip occurred in conjunction with the PORV actuation.
This challenge rate is clearly a minimum value since prior to the setpoint changes, the reactor did not necessarily trip every time a PORV opened.
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9 M licensees with B&W NSSS experienced reactor trips due to M M'%
the,,setpoints, these plants'(excluding Crystal River 3)
MLCPNfiEI4 The interval over which these observations were made is quite short and thus an accurate assessment of the time frequency cannot be made until a longer period has elapsed. Ilowever, 6 am e t== = u::r=.y v-:.. s:.-
Contact:
Glenn Kelly Ext. 27591 8006060 30 0
5 Crystal River 3 had five fecdwater transients in a onc conth period related to cr -- t : on '.'i rh onl: t h re - hG pumps enerating. gJnya&LWN.g po2nowmir-nn~srgiprantlygg4gc$,gKggag3 ga46,;i44WM:7 A
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Refercuce:
(1) 1.etter, G. C. Moore, Florida Power Corporaticn to R. A. Reid, NRC. Nove=ber 1!., 1979.
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Sanford L. Israel, Group Leader Sys tems Group Sulletins 5 Orders Task Force T. Nevak ( R. Cac M cc:
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.nadani L. Ras:coc:y G. Kelly i
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