ML20206J943
| ML20206J943 | |
| Person / Time | |
|---|---|
| Site: | Oconee  |
| Issue date: | 11/21/1988 |
| From: | Tucker H DUKE POWER CO. |
| To: | NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM) |
| References | |
| GL-88-11, NUDOCS 8811290197 | |
| Download: ML20206J943 (2) | |
Text
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th!II Tasa Duke her Company PO Box 331%
kr Presihnt
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Charlotte, N C 28242 Nuclear rmluction (704)]i3 4331 s
DUKEPOWER November 21, 1988 U. S. Nuclear Regulatorf Commission Documnt Control Desk Wasnington, D. C. 20555
Subject:
Oconee Nuc1 car Station Docket Nos. 50-269, -270, 28/
Response to GL 88-11 Gentlemen:
By letter dated July 12, 1988, NRC issued Generic Letter 88-11, "NRC Position on Radiation Embrittlement of
~2 actor Vessel Materials and its Impact on Plant Operations." GL 88-11 requires that within 180 days of the effective date of Reg. Guide 1.99, Revision 2, licensees should submit the results of their i :chnical analysis and a proposed schedule for whatever actions they propose to take. This letter is a preliminary response for 0 onee Nuclear Station.
The current pressure-temporature limit curves in Oconee Nucicar Station Technical Specifications were generated based on the methodology required by Reg. Guide 1.99, Revision 1 and reactor vessel surveillance program capsule data for 15 EFPY (Amendments Nos. 119/119/116). As of November 1988 Oconee Units 1, 2, and 3 had operated for approximately 10.5, 10.0, and 9.7 EFPYs, respectively. Therefore, these curves are projected to expire within the next approximately 6 calendar years when these units accumulate 15 EFPYs.
By letter dated October 31, 1988, Duke Power provided NRC the results of surveillance capsules OCI-C and OCII-E for Oconee Unit 1 and 2, respectively.
These capsulo results, which are based on Reg. Guide 1.99, Rnv. 2, projected a genurally lower fluence for vessel inside surface at the end of 32 EPPYs compared to the previous capsules' results.
Furtherncre, the shift in RT NDT both forging and weld materials calculated for 21 EFPYs was determined to be conservative with respect to predict'on methodology of Reg. Guide 190, Rev.
02.
Also, the capsule analyses demonstrated that the most limiting veld metal has adequate irradiated toughn<is proporties to assure safe operation of these units to 32 EFPYs.
Duke Power Company is currently reanalyzing the present 15 EFPY pressure-temperature limits. sing the most recent capsule data and methodology of f
8911290197 881121 PDR ADOCK OS000269 i 'I P
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U. S.* Nuclear Reguletory Commission November 21, 1988 Page Two R.G. 1.99, Rev. '4 to determine its impact.
Results of this reanalysis which will be used to generate a response to Generic Letter 88-11 will become available in January 1989. Duke anticipates to provide a response addressint the concerns of GL 88-11 by January 31, 1988.
Very truly yours,
).6 /L m
,11. B. Tucker
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.. MAH08.D2/lcs b
Attachments xc:
M. L. Ernst Acting Regional Administrator, Region II U. S. Nuclear Regulatory Commission 101 Marietta Street, NW, Suite 2900 Atlanta, Georgia 30323 ilelen Pastis Office of Nuclear Reactor Regulation U. S. Nuclear Regulatory Commission Washington, D. C.
20555 P.11. Skinner NRC Resident Inspector Oconee Nuclear Station s
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