ML19209D028
| ML19209D028 | |
| Person / Time | |
|---|---|
| Site: | Clinton  |
| Issue date: | 10/01/1979 |
| From: | James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | Gerstner W ILLINOIS POWER CO. |
| References | |
| NUDOCS 7910180624 | |
| Download: ML19209D028 (1) | |
Text
T}L f* **%g UNITED STATES o
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NUCLEAR REGULATORY COMMISSION o
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OCT 1 1979 Docket No. 50-461 Docket No. 50-462 I,llinois Power Company ATTN:
Mr. W. C. Gerstner Executive Vice President 500 South 27th Street Decatur, IL 62525 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, fa'mes~G. ga A -_
D. _.., _ L fepbfer Director
Enclosure:
IE Information Notice No. 79-24 cc w/ encl:
Central Files Director, NRR/DPM Director, NRR/ DOR PDR Local PDR NSIC TIC Mr. Dean Hansell, Office of Assistant Attorney General 1177 177 7910180{7
SSINS:
6870 Accession No:
7908220123 UNITED STATES
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' 6B i NUCLEAR REGULATORY COMMISSION A
OFFICE OF INSPECTION AND ENFORCEMENT T
WASHINGTON, D. C.
20555 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 approximately 10 minutes.
The long term blowdown of the water supplied under runout conditions by the auxiliary feedwater system had not been considered in the earlier analyses.
The corrective action is now under review by the owner, architect engineer, and NSSS supplier.
This Information Notice is provided as an early notificaticn 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 NRC 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 il77 178 4
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5 IE Information Notice No. 79-24 Enclosure October 1, 1979 Page 1 of 2 LISTING OF IE INFORMATION NOTICES 15 SUED IN LAST SIX MONTHS
.Information Subject Date Issued To
-Notice No.
Issued 79-10 Nonconforming Pipe 4/16/79 All power reactor Support Struts facilities with a CP 79-11 Lower Reactor Vessel Head 5/7/79 All holders of Reactor Insulation Support Problem OLs and cps 79-12 Attempted Damage to New 5/11/79 All Fuel Facilitier Fuel Assemblies Research Reactors, and Power Reactort 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 Cable Support Systems Facilities with a 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 Mile Island and Test Reactors with OLs 79-17 Source Holder Assembly Darage 6/20/79 All Hciders of Reactor Damage From Misfit Between OLs and cps 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 179 e
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6 IE Information Notice No. 79-24 Enclosure October 1, 1979 Page 2 of 2 LISTING 0F IE INFORMATION NOTICES ISSUED IN 1979 Information Subject Date Issued To N9tice No.
Issued h9-20 NRC Enforcement Policy 8/10/79 All Holders of Reactor NRC Licensed Individuals OLs and cps and Production Licensees 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 holoing LLs and cps 1177 180