ML19327A616
| ML19327A616 | |
| Person / Time | |
|---|---|
| Site: | Grand Gulf  |
| Issue date: | 07/03/1980 |
| From: | James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| To: | Stampley N MISSISSIPPI POWER & LIGHT CO. |
| References | |
| NUDOCS 8008060495 | |
| Download: ML19327A616 (1) | |
Text
'o UNITEJ 8TATES 8
NUCLEAR REGULATORY COMMISSION
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_, a REGION 11 o
101 MARlETTA ST N.W.. Sulf E 3100 Y4 ATLANTA, GEORGIA 30303 JLit 3 1980 In Reply Refar To:
RII:JP0s) 50-416 g 417,/
Mississippi Power and Light Company ATTN:
N. L. Stampley Vice President of Production P. O. Box 1640 Jackson, MS 39205 Gentlemen:
The enclosed IE Bulletin No. 80-17, is forwarded to you for information.
No written response is required.
If you desire additional informat.on regarding this matter, please contact this office.
Sincerdly,
-5 James P. O'Reilly Director
Enclosure:
IE Bulletin No. 80-17 cc w/ enc 1:
C. K. McCoy, Plant Manager f}
l 8008060
SSINS No.:
6820 Accession No.:
8005050076 UNITED STATES NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT JULY 3, 1980 IE BULLETIN N0. 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manual scram was initiated and all partially inserted rods were observed to drive inward, but 59 remained partially withdrawn.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high level in the SDV and bypassing for another short drain of the SDV, with the result that 47 rods remained partially withdrawn.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. Those that are presently shutdown shall perform the following steps pr' DUPLICATE DOCUMENT 1.
Within 3 days from the dai; teststoverifythattherd Entire document previously Discharge Volume (SDV) an i entered into system under:
t are operable and vent sys
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