ML19224C448
| ML19224C448 | |
| Person / Time | |
|---|---|
| Site: | Grand Gulf  |
| Issue date: | 06/20/1979 |
| From: | James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| To: | Stampley N MISSISSIPPI POWER & LIGHT CO. |
| References | |
| NUDOCS 7907020389 | |
| Download: ML19224C448 (1) | |
Text
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/ ** a' coq'o UNITED ST ATES NUCLEAR REGULATORY COMMISSION
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REGION il sol M ARitTT A ST., N W., SUITE 3100
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AT L ANT A, GEORGI A 30303
,t o B73 In Reply Refer To:
RII:JPO 50-416, 50-417 Mississippi Power and Light Company Attn:
N. L. Stampley Vice President of Production P. O. Box 1640 Jackson, Misaissippi 39205 Centlemen:
This Infornation 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 recorrend or request specific If you have questions regarding this matter, please contact licensee actions.
the Director of the appropriate FRC Regional Office.
Sincerely,
[r--James P. O'Rei Director
Enclosures:
1.
IE Information Notice No. 79-17 2.
List of Inforcation Notices Issued in 1979 271 2/l e
h
JUN 2 01979 Mississippi Power and Light Company cc w/ encl:
C. K. McCoy Plant Manager Post Of fice Box 756 39150 Port Gibson, Mississippi f
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8 3
271 272 4
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UNITED STATES NUCLEAR REGULATORY CO SISSION OFFICE OF INSPECTION AND ENFORCEFENT WASHINGTOS, D.C.
20555 June 20,1979 IE Information Notice No. 79-17 SOURCE HOLDER ASSEMBLY DAMAGE FROM MISFIT NMFN GRID PLATE Description of Circt= stances:
Recently, the NRC was informed of a problem at two Westinghouse IVR fac lies resulting from an apparent misfit between secondary source holder asse=b
- and the reactor upper grid plate.
The cisfit problem was first identified by Carolina Power & Light, licensee for H. B. Robinson Unit 2, who informed the NRC on M during the mined that two secondary source holder assecblies had been damaged stances.
l d che previous refueling in February 1978, by a misfit between the asse (i.e. 1/2 to 3/4 inch) between the source holder asse=bly hub and the g reactor upper grid plate.
~
Thia lack plate at the core locations _ containing thermocouple mixi The eleforna-ponents at the core location and of the source holder assemblies.
bly, however, tion also resulted in some bending of the fuel rods in the assem in no case did this bending result in fuel cladding perforation.
1 inforced the NRC that the on May 16, 1979, the licensee of D. C Cook Unit tr present refueling outage would be extended 15 to 2 e
They learned of the problem fro Westinghouse.
corren his misfit proble=.
Subsequently, the licensee's inspection revealed that the source holderTh assembly hubs were in contact with the vanes.from one asse=b source holder was found stuck in the assembly.
prior to return to operations.
The secondary source asse bly rods are normally inserted into rod cluster Each auch control assemblies and placed at syt=ctrical locations in the core.
d d
assembly contains a syr=ctrical grouping of four secondary source ro s anLocati between zero and twenty burnable poison rods.
T e lack A e i.
filled with a source or burnable p
^
of sufficient clearance for these DUPLICATE DOCUMENT only at the core locations which Entire document previb ly tered l
into system under:
h h h2h ANO No. of pages:
1
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