ML19225A534
| ML19225A534 | |
| Person / Time | |
|---|---|
| Site: | Hatch, Vogtle  |
| Issue date: | 06/20/1979 |
| From: | James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| To: | John Miller GEORGIA POWER CO. |
| References | |
| NUDOCS 7907190518 | |
| Download: ML19225A534 (2) | |
Text
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UNITED STATES
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NUCLEAR REGULATORY COMMISSION c
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.' E REGION il E
101 MARlETTA ST., N.W., &UITE 3100 g
AT LA NT A, G E OF.GI A 303o3 6
In Reply Refer To:
JUN 2 01979 RII:JPO 50-321, 50-366 50-424, 50-425 Georgia Powr Company Attn:
J. B. Miller, Jr.
Executive Vice President
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270 Peachtree Street, N. W.
Atlanta, Cecrgia 30303 Gentlemen:
Ihis Information Notice is provided as an estly notification of a possibly significant matter. It is expected that recipients will review the inferna-tion for possible applicability to their facilities. No specifte action or response is requested at this tice. If further NRC eva bations to indicate, an IE Circular or Bulletin will be issued to recccmend or request specific licensee actions. If you have questions regarding this matter, please contact the Director of the appropriate NRC Regional Off* m.
Sincerely, y
pJames P. O'Rei Director
Enclosures:
1.
IE Information Notice No. 79-17 2.
List of Information Noticas Issued in 1979 C
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415 352
JUN 2 0 Bfg Georgia Power Company.
cc w/ enc 1:
M. Hanry, Plant Manager Post Office Box 442 Baxley, Georgia 31513 C. E. Belflower Site QA Supervisor Post Office Box 442 Baxley, Georgia 31513 K. H. Gillespie Constraction Project Kanager Post Office Box 282 Waynesboro, Georgia 30830
~. E. D. Grover QA Site Supervisor Post Office Box 282 Waynesboro, Georgia 00830 1
415 353
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..s s-4, UNITED STATES i
NUCLEAR RECULATORY COMKISSION OTTICE OF INSPECTION RC ENTORCEMENT WASHINOTON, D.C.
20555 June 20,1979 IE Information Notice No. 79-17 50"RCE BOLDER ASSEMELY DA". AGE TRO'd. MISTIT B. ~~EEN ASSDSLY AND REACTOR UPPER CFlD PLATE Description of Circu= stances:
Recently, the NRC was inforr.ed of a problem at two Westinghouse W R facilities resulting froc an apparent u.lsf ac between secondary source holder asse=blies and the reactor upper grid plate.
The misfit proble= vas first identified by Carolina Power & Light, licensee for B. B. Robinson Unit 2, who inforned the NRC on May 6 1979, of the circum-stances. During the current refueling outage at B. B. Robinson 2, CP&L deter-mined that two secondary source holder asse:blies had been da: aged during the previous refueling in Tetruary 1978, by a misfit between the asse=bly and the r
reactor upper grid plate. The misfit resulted from insufficient clearance (i.e. 1/2 to 3/4 inch) between the source holder asse=bly hub and the grid plate at the core locations containing thermocouple cixing vanes. This lack of sufficient clearance caused minor defort.ation of the upper grid plate cc:n-ponents at the core location and of the source holder asse=blies. The deforma-I-
tien airo resulted in some bending of the fuel rods in the asse=bly, bovever, in no case did this bending result in fuel cladding perforatitin.
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On May 16, 1979, the licensee of D. C. Cook Unit 1 inforted the NRC that the present refueling outage would be extended 15 to 20 days to reenve the reactor 5.;
head, which had already been reinstalled following co=pletion of refueling, to correct this misfit problem. They learned of the problem froc Westinghouse.
Subsequently, the licensee's inspection revealed that the source holder j.
asse:bly bubs were in contact with the vanes. The source holder was recoved fron one asse:bly readily with no apparent ds=aEe while in the other the source holder was found stuck in the assecbly. The proble: vas corrected prior to return to operations.
The secondary source assembly rods are cores 117 inserted into rod cluster control assemblies and placed at syt.etrical locations in the core. Each such asse:bly contains a syr: etrical grouping of four secondary source rods and betvcen aero and twenty burnable po'~
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filled with a source or burnable po DUPLICATE DCCUMENT h
of sufficient clearance for these a Qj only at the core locations which to Entire document previously entered ii into system under:
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