ML19210D783
| ML19210D783 | |
| Person / Time | |
|---|---|
| Site: | La Crosse File:Dairyland Power Cooperative icon.png |
| Issue date: | 11/16/1979 |
| From: | James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | Linder F DAIRYLAND POWER COOPERATIVE |
| References | |
| NUDOCS 7911280064 | |
| Download: ML19210D783 (1) | |
Text
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,j oy'o, UNITED STATES l'
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'n NUCLEAR REGULATORY COMMISSION E
REGION 111 5-f
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799 ROOSEVELT ROAD o,
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GLEN ELLYN, ILLINOIS 60137 Docket No. 50-409 Dairyland Power Cooperative ATTN:
Mr. F. W. Linder General Manager 2615 East Avenue - South La Crosse, WI 54601 Gentlemen:
The enclosed IE Information Notice No. 79-27 provides inforination with regard to the sequence of events thst followed incidents involving steam generator tube ruptures at two PWR units.
Sincerely,
- i. 6U s~[
g James G. Keppler I Director
Enclosures:
1.
IE Information Notice No. 79-27 2.
Recently Issued IE Information Notices cc w/er.cls:
Mr. R. E. Shimshak, Plant Superintendent Central Files Director, NRR/DPM Director, NRR/ DOR PDR Local PDR NSIC TIC Anthony Roisman, Esq.,
Attorney
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1435 509 7 9112 80 0 M
SSINS No.:
6870 Accession No.:
UNITED STATES NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT WASHINGTON D.C.
20555 November 16, 1979 IE Information Notice No. 79-27 STEAM GENERATOR TUBE RUPTURES AT TWO PWR PLANTS Description of Circumstances:
In recent months two incidents involving stehm generator tube ruptures have occurred.
In both instances, the units were cooled down and placed in the residual heat removal mode with existing procedures.
Event of June 25, 1979 at the Doel 2 Nuclear Power Plant in Belgium 4
The first event occurred on June 25, 1979, at the Doel 2 nuclear power plant in Belgium. The Doel unit is a 390 Mwe Westinghouse two-loop reactor.
The event consisted of a rupture of several tubes in the loop B steam generator.
The resultant leakage between the primary and secondary systems was estimated to be 125 gpm.
The event started when the plant " : N ted up after a shutdown caused by a malfunction of the main steam isolation Give.
At the time of the incident the primary coolant pressure was:
2233 psi and the temperature:
491 F.
The reactor remained subcr!'ical throughout the event.
The first indication of abnormal behavior was a rapid decrease of the primary system pressure (approximately:
28 psi / min.).
This was followed by the sequence of events listed below:
Time. min.
1.
Itcrease of charging flow demand, requiring startup of a second 1.8 charging pump.
2.
Automatic isolation of the C 3.
Shut off of the pressurizer j '$
DUPLICATE DOCUMENT pressurizer.
Entire document previously entered into system under:
ANO l
No. of pages:
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