ML19254C979
| ML19254C979 | |
| Person / Time | |
|---|---|
| Site: | Humboldt Bay, Diablo Canyon |
| Issue date: | 10/01/1979 |
| From: | Engelken R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V) |
| To: | Crane P PACIFIC GAS & ELECTRIC CO. |
| References | |
| NUDOCS 7910190214 | |
| Download: ML19254C979 (1) | |
Text
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Io, UNITED STATES g y ; ),3 y,g NUCLEAR REGULATORY COMMISSION g, pf '
f, REGION V 0, ' p.,
., J 1990 N. CALIFORNI A POULEVARD
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e' SUITE 202, WALfJUT C 7E E K PLAZA WALNUT CHEEK, CAllf 3RNIA 9459G October 1, 1979 Docket flos. 50-133 50-275 50-323 Pacific Gas and Electric Company 77 Beale Street San Francisco, California 94106 Attention:
Mr. Philip A. Crane, Jr.
Assistant General Counsel Gentlemen:
The enclosed Information Notice provides ni.
ation with regard to an analysis that identifies an event that could result in overpressurization of containment at a pressurized water reactor.
Sincerely, b'Yl'Iw, c ( d --
R. H. Engelken Director
Enclosures:
1.
Information tiotice 79-24 2.
List of IE Information flotices Issued in the Last Six Months cc w/ enclosures:
W. Barr, PG&E W. Raymond, PG&E R. Ramsay, PG&E, Diablo Canyon E. Weeks, PG&E, Humboldt Bay J. Worthington, PG&E 118? 005
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6870 Accession fio:
7908220123 UNITED STATES NUCLEAR REGULATORY COMMISSION n
t ara 0FFICE OF INSPECTION AND ENFORCEMEfC
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La October 1, 1979 IE Information tiotice tio. 79-24 OVERPRESSURIZATION OF CONTAINMEllT 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 fecdwater 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 notification of a possibly significant matter that is still under review by the tiRC 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 requirad.
No written response to this Information Notice is required.
If you have any question s agarding this matter pleasa con act the Director of the appropriate NRC Regional O M ce.
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iE Information Notice No. 79-24 Enclosure October.1, 1979 Page 1 of 2 LISTING OF IE INFORMATION NOTICES ISSUED IN LAST S'X MONTHS Information Subject Date Issued To Notice No.
Issued 79-10 Nonconforming Pipe 4/16/79 All power reactor Support Struts facili'ies with a CP 79-11 Lower Reactor Vesse 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 Facilities Fuel Assemblies Research Reactors, and Power Reactors with an OL or CP 79-13 Indication of Low Hater 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 Damage 6/20/79 All Holders 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 s
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IE I'nformation Notice No. 79-24 Enclosure October 1, 1979 Page 2 of 2 LISTING OF IE INFORMATION NOTICES ISSUED IN 1979 Information Subject Date Issued To Notice No.
Issued 79-20 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 pow. and research Burial u.- 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 1189 008