ML19256B738
| ML19256B738 | |
| Person / Time | |
|---|---|
| Site: | Haddam Neck File:Connecticut Yankee Atomic Power Co icon.png |
| Issue date: | 08/13/1979 |
| From: | Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | Counsil W CONNECTICUT YANKEE ATOMIC POWER CO. |
| References | |
| NUDOCS 7908280257 | |
| Download: ML19256B738 (1) | |
Text
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KING OF PRUSSIA, PENNSYLVANIA 19406 Docket No. 50-213 AUG13l379 Connecticut Yankee Atomic Power Company ATTN:
Mr. W. G. Counsil Vice President - Nuclear Engineering and Operations P. O. Box 270 Hartfard, Connecticut 05101 Gentleman:
Enclosed is IE Bulletin 79-21 which requires action by you with regard to your PWR power reactor facility (ies) with an operating license.
Should you have any questions regarding this Bulletin or the actions required by you, please contact this office.
Sincerely, ik N'
Boyce H. Grier Director
Enclosures:
1.
List of IE Bulletins Issued in tne Last 6 Months cc w/encls:
R. Graves, Plant Superintendent D. G. Diedrick, Manager of Quality Assurance J. R. Himmelwright, Licensing Safeguards Engineer 79082 80g 5 7
ENCLOSURE 1 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 TEMPERATURE EFFECTS ON LEVEL MEASUREMENTS Uescription of Circumstances:
On June 22, 1979, Westinghouse Electric Corporation reported, to NRC, a potential substantial safety hazard under 10 CFR 21.
The report, Attachment No. 1, addresses the effect of increased containment temperature on the reference leg water column ar 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, provie
- e. oneous information during post-accident monitoring.
Attachment No. 1 adjrssses only a Westinghouse steam generator 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 oost-ac-cident ambient temperatures on the indicated water level to determ'.e iy change in indicated level relative to actual water level.
This evaluatio include other sources of error including the effects of varying flu.
pressure and flashing of reference leg to steam on the water level measure-ments. The results of this evaluation should ue presented in a tabular f9rm similar to Tables 1 and 2 of Attachment 1.
DUPLICATE DOCUMENT
- Boiling water reactors hav NRC to provide similar inf Entire document previously entered into system under:
ANO 7QO2O R O l9 ]
No. of pages:
12