ML19327A610
| ML19327A610 | |
| Person / Time | |
|---|---|
| Site: | Dresden, Quad Cities  |
| Issue date: | 07/03/1980 |
| From: | James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | Reed C COMMONWEALTH EDISON CO. |
| References | |
| NUDOCS 8008060470 | |
| Download: ML19327A610 (1) | |
Text
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'o UNITED STATES
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NUCLEAR REGULATORY COMMISSION o
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-r REGION lli I
7M ROOSEVELT ROAD O
GLEN ELLYN. ILLINOIS So137 JUL' 3 580 Docket Nos. 50-10, 50-237, 50-249; 50-254, 50-265 Commonwealth Edison Company ATTN:
Mr. Cordell Reed Vice President Post Office Box 767 Chicago, IL 60690 Gentlemen:
The enclosed IE Bulletin No. 80-17, is forwarded for action. Prepare to perform the scram tests contained in the bulletin; however, the 20-day time clock for completing will begin upon notification by telephone from the IE Regional Office. The testing shall be performed at directed un-less shutdown would severely impact the power reliability in your area as shown by appropriate and timely documentation to the Director of the Office of Inspection and Enforcement.
A written response to the bulletin is required.
If you desire additional information regarding this matter, please cor. tact this office.
Sincerely, hfar ka James G. Kep M Director
Enclosure:
IE Bulletin No. 80-17 cc w/ encl:
Mr. D. L. Peoples, Director Director NRR/ DOR of Nuclear Licensing PDR Mr. B. B. Stephenson, Local PDR Station Superintendent NSIC Mr. N. Kalivianakis, TIC Station Superintendent Mr. Dean Hansell, Office of Central Files Assistant Attorney General Director, NRR/DPM 8008060QD g
SSINS No.:
6820 Acce.sion No.:
8005050076 UNITED STATES NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT JULY 3, 1980 IE BULLETIN NO. 80-17 FAILURE OF 76 0F 185 CONTROL RODS TO FULLY INSERT DURING A SCRAM AT A BWR Description of Circumstances:
On June 28, 1980, 76 of the 185 control rods failed to fully insert during a routine shutdown at TVA s Browns Ferry Unit No. 3 located at Athens, Alabama. The reactor was manually scrammed from about 30 percent power in accordance with routine shutdown procedures.
The shutdown was initiated to repair the feedwater system.
The 76 control rods that failed to fully insert were all on the east side of the core.
Following scram discharge volume (SDV) high level bypass and a short drain period of the SDV, a second manual scram was initiated and all partially inserted rods were observed to drive inward, but 59 remained partially withdrawn.
A third manual scram was made, again following high level in the SDV and bypassing for another short drain of the SDV, with the result that 47 rods remained partially withdrawn.
Following a longer drain of the SDV, an automatic scram occurred that was initiated by a scram discharge volume tank high water level signal when the scram reset switch was placed in " Normal"; with this scram all remaining rods fully inserted.
The total time elapse from the initial scram to the time that all rods were inserted was approximately 15 minutes.
Core coolant flow, temperature and pressure remained normal for plant conditions.
The unit is now shutdown and additional testing indicates that a possible cause of the malfunction was the retention of a significant amount of water in the east bank scram discharge volume.
In view of these interim findings and pending results of continued investigation, the following actions are to be taken.
Actions To Be Taken By Licensees:
All General Electric Boiling Water Reactors with operating licenses which are operating at any power on the date of this Bulletin shall perform the following steps in the time stated.
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perform the following steps prior tt DUPLICATE DOCUMENT Within3daysfromthedateofff 1.
tests to verify that there is ij Entire document previously entered into system under:
DischargeVolume(SDV)andasst]
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areoperableandventsystemi}l ANo h
No. of pages:
5