ML19209D034
| ML19209D034 | |
| Person / Time | |
|---|---|
| Site: | Callaway  |
| Issue date: | 10/01/1979 |
| From: | James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | Bryan J UNION ELECTRIC CO. |
| References | |
| NUDOCS 7910180636 | |
| Download: ML19209D034 (1) | |
Text
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NUCLEAR REGULATORY COMMISSION
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8 799 ROOSEVELT ROAD GLEN ELLYN. ILLINOIS 6o137 g,**..'+
I Docket No. 50-483 Docket No. 50-486 Union Electric Company hTTN:
Mr. John K. Bryan Vice President - Nuclear P. O. Box 149 St. Louis, M0 63166 Gentlemen:
The enclosed IE Information Notice No. 79-24 provides information with regard to an analysis that identifies an event that could result in over-pressurization of containment at a pressurized water reactor.
Sincerely,
%A Y" AN
(/JamesG.Ke7 pier Director
Enclosure:
IE Information Notice No. 79-24 cc w/ enc 1:
Mr. W. H. Weber, Manager, Nuclear Construction Central Files Director, NRR/DPM Director, NRR/ DOR PDR Local PDR NSIC TIC Region I & IV Ms. K. Prey Hon. C. J. Frass, Chairman Missouri Public Service Commission 1177 201 i
1 7 91018o 63 C 9
SSINS:
6870 Accession No:
7908220123 UNITED STATES NUCLEAR REGULATORY COMMI.,SION OFFICEOFINSPECTIONANDENFORCEMENTy WASHINGTON, D. C.
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October 1, 1979 IE Information Notice No. 79-24 OVERPRESSURIZATION OF CONTAINMENT OF A PWR PLANT AFTER A MAIN STEAM LINE BREAK Virginia Electric and Power Co. submitted a report dated September 7, 1979 that identified a deficiency in the original analyses of containment pressurization as a result of a steam line break for North Anna Power Station, Units 3 and 4.
Stone and Webster Engineering Corporation performed a reanalyses of containment pressure following a main steam line break and determined that, if the auxiliary feedwater system continued to supply feedwater at runout conditions to the steam generator that had experienced the steam line break, containment design pressure would be exceeded in apptoximately 10 minutes. The long term blowdown of the water supplied under runout conditions by the auxiliary feedwater system had net been considered in the earlier analyses. The corrective action is now under redew by the owner, architect engineer, and NSSS supplier.
This Information Notice is provided as an early notification of a possibly significant matter that is still under review by the NRC staff.
It is expected that recipients will review the information for possible applicability to their facilities.
No specific action or response is requested at this time.
If HRC evaluations so indicate, further licensee actions may be requested or required.
No written response to this Information Notice is required.
If you have any questions regarding this matter please contact the Director of the appropriate NRC Regional Office.
Enclosure:
List of IE Information Notices Issued in the Last Six Months 1177 202 L-
Enclosure IE Information Notice No. 79-24 Page 1 of 2
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October 1, 1979 LISTING OF IE INFORMATION NOTICES
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ISSUED IN LAST SIX MONTHS
,Information Subject Date Issued To Issued (Notice No.
79-10 Nonconforming Pipe 4/16/79 All power reactor facilities with a Support Struts CP 79-11 Lower Reactor Vessel Head 5/7/79 Ail holders of Reactor Insulation Support Problem OLs and cps 79-12 Attempted Damage to New 5/11/79 All Fuel Facilities Research Reactors, Fuel Assemblies and Power Reactors with an OL or CP 79-13 Indication of Low Water 5/29/79 All Holders of Reactor Level in the Oyster Creek OLs and cps Reactor 79-14 NRC Position of Electrical 6/11/79 All Power Reactor Facilities with a Cable Support Systcms CP 79-15 Deficient Procedures 6/7/79 All Holders of Reactor OLs and cps 79-16 Nuclear Incident at Three 6/22/79 All Research Reactors and Test Reactors Mile Island with OLs 79-17 Source Holder Assembly Damage 6/2D/79 All Holders of Reactor OLs and cps Damage From Misfit Between Assembly and Reactor Upper Grid Plate 79-18 Skylab Reentry 7/5/79 All Holders of Reactor OLs 79-19 Pipe Cracks In Stagnant 7/17/79 All Holders of Reactor Borated Water Systems At OLs and cps PWR Plants 1177 203
IE Information Notice No. 79-24 Enclosure October 1, 1975 Page 2 of 2 LISTING OF IE INFORMATION NOTICES ISSUED IN 1979 Information Subject Date Issued To Rotice No.
Issued 79-20 NRC Enforcement Policy 8/10/79 All Holders of Reactor NRC Licensed Individuals OLs and cps and Production Licenstes with Licensed Operators 79-21 Transportation and Commercial 9/7/79 All power and research Burial of Radioactive Material reactors with OL's 79-22 Qualification of Control 9/14/79 All power reactor Systems facilities with operating licenses and construction permits.
79-23 Emergency Diesel Generator 9/26/79 All Power facilities Lube Oil Coolers holding OLs and cps 1177 204 i
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