ML20095E542

Provides Revised Response to GL 94-03, IGSCC of Core Shroud in Bwrs

ML20095E542
Person / Time
Site:	Clinton
Issue date:	11/22/1995
From:	Jackie Cook ILLINOIS POWER CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
GL-94-03, GL-94-3, JGC-494-95, L30-95(11-22)LP, U-60216, NUDOCS 9512150148
Download: ML20095E542 (3)

Text

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Ilknois Power Company  !

Cl ton Pow r Stabon Chnton. !L 61727 Tel 217 935-5623

, Fax 217 935 4632 John G. Cook inmens """2;;;

u P4MER JGC-494-95 L30-95(11 -22 )LP November 22, 1995 8G.120 k

Docket No. 50-461  :

Document Control Desk ,

Nuclear Regulatory Commission Washington, D.C. 20555

[

Subject:

Illinois Power's (IP's), Clinton Power Station's (CPS's) R.evised Response to Generic Letter (GL) 94-03, "Intergranular Stress Corrosion Crackina of Core Shrouds in Boiling Water Reasign"

Dear Sir:

IP provided its GL 94-03 response to the NRC in letters U-602364, dated September 24,1994 and U-602369 dated December 14,1994. The purpose of this letter is to revise IP's response to the NRC regarding when the CPS core shroud will be  ;

inspected. IP committed, in letter U-602369 to inspect the core shroud during the sixth refueling outage (RF-6) scheduled for October 1996.  !

On September 2,1994, the BWR Vessels & Internals Project (BWRVIP) initiated GENE-523-113-0894, "BWR Core Shroud Inspection and Flaw Evaluation Guidelines." l This document listed CPS as a Category "A" plant. The plant characteristics for this I category are 304L plants (plants with 304L stainless steel, carbon content 0.04 wt.% or less, as the shroud base material) with less than 8 hot operating years and an average conductivity at or below 0.30 pS/cm during the first 5 cycles of operation. Presently, the calculated hot operation years at CPS at the start of RF-6 will be 7.63 years (revised from the 7.96 years in U-602369), and the average conductivity during the first five operating cycles is 0.186 pS/cm, thus categorizing CPS as a Category "A" plant. GENE-523-113- l 0894 states that such plants have shown very low likelihood of cracking, demonstrated by I field experience with the shroud and other components; therefore, an inspection is not l necessary. l The NRC letter, " Evaluation of'BWR Shroud Cracking Generic Safety  !

Assessment, Revision 1,' GENE-523-A107P-0794, August 5,1994 and 'BWR Core Shroud Inspection and Evaluation Guidelines,' GENE-523 113-0894, September 2,1994,"

l to Mr. J. T. Beckman, Chairman BWR/ VIP, acknowledged agreement with the

categorization of BWR plants into three groups (Category A, B, or C) and with the proposed guidance for establishing schedules for the inspection of Category A and B plants.

~ 9512150148 951122 I PDR ADOCK 05000461 P ._ _

PDR / I '

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f U-602516 Page 2 Based on the information contained herein,' CPS will not conduct an inspection  ;

during RF-6. The core shroud inspections documented in our response to GL 94-03 will instead be performed during RF-7 scheduled for March 1998.

Attachment 1 provides an affidavit supporting the facts set forth in this letter. ,

i Sincerely yours, l

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. G. k i ice President i

JSP/csm  ;

i Attachment cc: NRC Clinton Licensing Project Manager l NRC Resident Office, V-690 l Regional Administrator, Region III, USNRC .i Illinois Department of Nuclear Safety  !

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>- Attachment 1 l to U-602516 ,.

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l J. G. Cook, being first duly sworn, deposes and says: That he is Vice President of the l

Nuclear Program at Illinois Power (IP), Clinton Power Station (CPS); that this letter ,

l supplying IP's response to Generic Letter 94-03 has been prepared under his supersision j

and direction; that he knows the contents thereof; and that to the best of his knowledge ,

l and belief said letter and the facts contained therein are true and correct.  !

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Date: This 'Ak day ofNovember 1995.

Signed:

J. G. Cook s,- _

l l STATE OF ILLINOIS l SS. 'OmCut mga

) Mhm a.as 71,.o ; //- COUNTY J py

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i Subscribed and sworn to before me this #3" day of November 1995.

l a)Ma sWJ/

4 (Notary Public)//