ML020910600
| ML020910600 | |
| Person / Time | |
|---|---|
| Site: | Oconee  |
| Issue date: | 03/19/2002 |
| From: | Mccollum W Duke Energy Corp |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| IEB-01-001 | |
| Download: ML020910600 (2) | |
Text
Duke Duke Energy kEnergy.
Oconee Nuclear Station 7800 Rochester Highway Seneca, SC 29672 W R. McCollum, Jr.
(864) 885-3107 OFFICE Vice President (864) 885-3564 FAX March 19, 2002 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555-0001
Subject:
Oconee Nuclear Station Unit 1 Docket Number 50-269 Supplementary Information Concerning Duke Energy Corporation Response to NRC Bulletin 2001 -01
Reference:
Letter, Duke to NRC, "Response to NRC Bulletin 2001-01: Circumferential Cracking of Reactor Pressure Vessel Head Penetration Nozzles," dated August 31, 2001 The referenced letter provided Duke Energy Corporation's (Duke) response to NRC Bulletin 2001-01. Duke's response committed to volumetrically inspect any Control Rod Drive Mechanism (CRDM) Reactor Vessel Head (RVH) penetration nozzle that is not verified by analysis to have a positive gap in the shrink fit annulus between the reactor vessel head and the CRDM nozzle. This commitment was included in the referenced letter due to a previous analysis of Framatome-ANP (FRA) shrink fit data on penetration nozzle No. 69 at Oconee Unit 1 could not verify a gap adequate for a valid qualified visual inspection. All other Oconee Units 1, 2, and 3 CRDM penetration nozzles had an adequate gap for a valid qualified visual inspection.
At a meeting with the NRC Staff on September 7, 2001, Duke indicated that a volumetric inspection of nozzle No. 69 would be performed at the next refueling outage. The original analysis for penetration No. 69 was based on final bore dimensions from a list of nozzles to be rehoned. Since the completion of the original analysis, FRA has located additional fabrication records that indicate the dimension used for the original nozzle No. 69 shrink fit analysis was too small and that penetration No. 69 had not been rehoned. Accordingly, the dimensions on earlier records of penetration No. 69 dimensions should be used. Verification of this conclusion is provided by comparing the previous ID dimensions to the dimensions on the rehone list. If the penetration had been rehoned, the penetration ID should have been slightly larger following the rehoning process, when in fact; the rehone list had significantly smaller ID dimensions. This new information indicates that a qualified visual inspection can be completed on Penetration No.
69 on Oconee Unit 1.
U. S. Nuclear Regulatory Commission March 19, 2002 Page 2 Since a qualified visual inspection can be performed on all Unit 1 CRDM RVH penetration nozzles, the above described commitment to perform volumetric inspection is fulfilled.
If you have any questions regarding this submittal, please contact Robert Douglas at 864-885-3073.
Very Truly Yours, William R. McCollum, Jr.
Site Vice-President, Oconee Nuclear Station xc w/att:
NRR Project Manager Regional Administrator, Region II Senior Resident Inspector South Carolina Dept. of Health & Environmental Control