ML19224C449
| ML19224C449 | |
| Person / Time | |
|---|---|
| Site: | Summer  |
| Issue date: | 06/20/1979 |
| From: | James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| To: | Mary Johnson SOUTH CAROLINA ELECTRIC & GAS CO. |
| References | |
| NUDOCS 7907020391 | |
| Download: ML19224C449 (1) | |
Text
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, /pn nuc UNITED ST ATES
'o NUCLEAR REGULATORY COMMISSION s ^^#(f,T n 8 ' ',,.
REGION il
..E 101 Manit TT A sT., N W, SulT E 3100 k
F AT L ANT A. G E oRGI A 30303
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we In Reply Refer To:
RII:JPO Scr-395 South Carolina Electric and Gas Conpany Attn:
M. C. Johnson, Vice President Specisi Services and Purchasing Post Office Box 764 Columbia, South Carolina 29218 Centlemen:
Ihis Information Notice is provided as an early notification of a possibly It is expected that recipients will review the informa-significant matter.
tion for possible applicability to their facilities. No specific action or If further NRC evaluations so indicate, response is requested at this time.
an IE Circular or Bulletin vill be issued to recor: mend or request specific If you have questions regarding this matter, please contact licensee actions.
the Director af the appropriate NRC Regional Office.
Sincerely,
[r -Janes P, O'Rei Director
Enclosures:
1.
IE Information Nor'.e No. 7 9-17 2.
List of Information Notices Issued in 1979 271 274
@9uv02 1l W
JUN 2 C E75 South Carolina Electrie,
- .nd Gas Cocpany cc 9/ encl:
T. B. Conners, Jr.
Con.ers, Moore and Corber 171.7 Fetnsylvania Avenue, N.W.
Washington, D.C.
20006 A. A. Seith Quality Assurante Post Office Box 8 29065 Jenkinsville, South Carolina O. S. Bradbac, Manager Nuclear Operations Post Office Box 8 29065 Jenkinsville, South Carolina e
l 271 275' O
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f UNITED STATES NUCLEAR RECULATORY COMMISSION OFFICE OF INSPECIION AC ENTORCEMENT WASHINGTON, D.C.
20555 June 20, 1979 IE Information Notice No. 79-17 SOURCE HOLDER ASSESLY DAu. ACE FROM MIST 1T BETi'EEN ASSESLY AND REACTOR UFFER CRID PLATE Description of Circumstances:
Recently, the NRC was infomed of a problem at two Westinghouse Fb'R f acilities
- resulting fro = an apparent risfit between secondary source holder asse=blies and the reactor upper grid plate.
i.
The cJefit proble= vas first identified by Carolina Power & Light, licensee for B. B. Robinson Unit 2, who inforced the NRC on May 6,1979, of the cireten-d During the current refueling outaFe at B. B. Robinson 2 C?&L deter-stances.
mined that tvo seconden source holder assecblie, had been damaged during the
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previous refueling in February 1978, by a misfit between the asse=bly and the reactor upper grid plete. The misfit resulted froc insufficient clearance
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(i.e. 1/2 to 3/4 inch) between the source holder asse=bly hub and the grid plate at the core locations _ containing themocouple mixing vares. This lack of sufficient clearance caused cinor defor=ation of the upper grid plate com-8; The defor=a-ponents at the cose location and of the source helder assemblies.
.t tion also resulted in so=e bending of the fuel rods in the asse=bly, however, in no case did this bending result in fuel cladding perforation.
On May 16, 1979, the licensee of D. C. Cook Unit 1 inforced the NRC that the
- j present refueling outage vould be extended 15 to 20 days to remove the reactor head, which b d already been reinstalled following conpletion of refueling, to correct this misfit problem. They learned of the problem fro: Westinghouse.
Subsequently, the licensee's inspection revealed that the source holder asse bly hubs were in contact with the vanes. The source holder was removed one asse=bly readily with no apparent datage while in the other the fro:
source holder was found stuck in the asse=bly. The probic: vas corrected prior to return to operations.
The secondary source asse:bly rods are corr.sily inserted into rod cluster Each such control asse:blies and placed at syr.=ctrical locations in the core.
assently contains a sytnetrical grouping of four secondary source rods and Locations in the asse bly not betvcen zero and twenty burnable poison rods.
illied vfth a source or burnable poi 2
2/O of sufficient clearance for these so DUPLICATE DOCUMENT only at the core locations which con I
Entire document previously entered into system under:
1 h h h)M ANO No. of pages:
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