ML19207C191
| ML19207C191 | |
| Person / Time | |
|---|---|
| Site: | Cooper  |
| Issue date: | 08/13/1979 |
| From: | Seyfrit K NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV) |
| To: | Pilant J NEBRASKA PUBLIC POWER DISTRICT |
| References | |
| NUDOCS 7909100129 | |
| Download: ML19207C191 (1) | |
Text
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UNITED STATEC y
PDR S y }AiI Wp,..q7 g NUCLEAR REGULATORY COMMISSION g,p g c
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'I j' ARLINGTON, TEXAS /G012 August 13, 1979 Docket No.
50-298 Nebraska Public Power District ATTN:
J. M. Pilant, Director Licensing & Qaality Assurance Post Office Box 499 Columbus, Nebraska 63601 Gentleaan:
The enclosed IE Bulletin 79-21 is forwarded to you for information. No written response is required.
If you desire additional information regarding this matter, please contact this office.
Sincerely, 4
Karl V. Seyfrij Director
Enclosures:
1.
IE Eulletin No. 79-21 2.
Listing of IE Bulletins Issued in Last 6 Months cc:
L.
C.
Lessor, Superintendent Cooper Nuclear Station Post Office Box 98 Brownville, Nebraska 68321
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UNITED STATES NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT WASHINGTON, D.C.
20555 IE Bulletin No. 79-21 Date: August 13, 1979 Page 1 of 2 TEMPERATLTE EFFECTS ON LEVEL MEASUREMENTS Description of Circumstances:
On June 22, 1979, Westinghouse Electric Corporation reported to NRC a potential substantial safety hazard under 10 CFR 21.
The report, Enclosure No. 1, addresses the effect of increased containment temperature on the reference leg water column and the resultant effect on the indicated steam generator water level. This effect would cause the indicated steam generator level to be higher than the actual level and could delay or prevent protection signals and could also provide erroneous information during post-accident monitoring.
Enclosure No. I addresses only a Westinghouse steam generatcr reference leg water column; however, safety related liquid level measuring systems utilized on other steam generators and reactor coolant systems could be affected in a similar manner.
Actions To Be Taken By Licensees:
For all pressurized water power reactor facilities with an operating license:*
1.
Review the liquid level measuring systems within containment to determine if the signals are used to initiate safety actions or are used to provide post-accident monitoring information.
Provide a description of systems that are so employed; a description of the type of reference leg shall be included, i.e., open column or sealed reference leg.
2.
On those systems described in Item 1 above, evaluate the effect of post-accident ambient temperatures on the indicated water level to determine any change in indicated level relative to actual water level.
This evaluation must include other sources of error including the effects of varying fluid pressure and flashing of reference leg to steam on the water level measure-ments. The results of this evaluation should be presented in a tabular form similar to Tables 1 and 2 of Enclosure 1.
3.
Review all safety an,1 control setpoints derived from level signals to verify that the setpoints will initiate the action required by the plant safety
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analyses throughout the range of a:
- >t,1y
- instrumentation, including acciden
" U ATE DOCUMENT these setpoints.
Entire document previously entered into system under:
- Boilir.g water reactors have been regt the NRC to provide similar informatic oho}O[
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No. of pages:
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