ML19321A492

Interim Deficiency Rept Re Nonconforming Elbow in two-inch Drain Line from Reactor Pressure Vessel.Foreign Matl Found in Elbow.Removal of Elbow Scheduled for Wk of 800714.Final Rept Will Be Submitted Late Aug 1980

ML19321A492
Person / Time
Site:	Clinton
Issue date:	07/14/1980
From:	Koch L ILLINOIS POWER CO.
To:
References
U-1056, NUDOCS 8007230518
Download: ML19321A492 (2)

Text

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s U-0156 ILLINOIS POWER COMPANY f .my. Ll4-80(07-14)-9 d.

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50] SOUTH 27TH STREET. DECATUR. ILLINotS 62525 July 14, 1980 Mr. James G. Keppler Director, Region III

, Office of Inspection and Enforcement

>[- U.S. Nuclear Regulatory Commission i .799 Roosevelt Road ,

Glen Ellyn, Illinois 60137

Dear Mr. Kecc.ler:

~

Clinton Power Station Unit 1 -

Docket No. 50-451 Construction Permit No. CPPR-137

. On June 20, 1980, Illinois Power Co=pany verbally notified Mr. John Neisler, NRC Region III, cf a potential reportable deficiency per 10CFR50.55(e). We had-identified at that time a suspected noncon-forming elbow installed in the two-inch drain line from the reactor pressure vessel (RPV) for Clinton Power Station Unit 1.

Subsecuently, we initiated an investigation of the potential report-able c.eficiency. Our investigation has not been completed. However, the following preliminary information has been developed to serve as an interim report:

A. Potential Problem - Radiographs of the field weld to the second 900 elbow of the RPV drain line, downstream from the RPV, revealed a one-inch oval discontinuity at the inside surface located at the outside radius of the elbow. Some foreign material was found inside the elbow. Subsequent investigation of the discontinuity has shown a wall-thickness as small as 0.254-inch, which compares to a nominal wall thickness of 0.354-inch for the two-inch Schedule 160 elbow.

B. Resolution Approach - We plan further investigations and analyses of the elbow after its removal fro: the drain line. Removal is tentatively-scheduled for the week of July 14.

C. We anticipate an additional thirty days will be required to '

complete the investigation. We w_ I file a final report about mid to late August, 1980.

(3el9 800723o$1s S /e

o p U-0156 Ll4-80(07-14)-0 Mr. James G. Keppler July 14, 1980 Page 2 If you have any con:ments with regard to this information, please notify me as appropriate.

Sincerely i

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. .K h Vice President GEW:dl - - ..

cc: Director, Cffice of I&E, NRC, Washington, D.C.

H. H. Live = ore, NRC Resident Inspector

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