ML033290423
| ML033290423 | |
| Person / Time | |
|---|---|
| Site: | Cook  |
| Issue date: | 11/14/2003 |
| From: | Zwolinski J Indiana Michigan Power Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| AEP:NRC:3455 | |
| Download: ML033290423 (4) | |
Text
Indiana Michigan Power Company 500 Circle Drive Buchanan, MI 49107 1395 INDIANA MICHIGAN POWER November 14,2003 AEP:NRC:3455 Docket No:
50-316 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Mail Stop O-PI-17 Washington, DC 20555-0001 Donald C. Cook Nuclear Plant Unit 1 STEAM GENERATOR TUBE INSERVICE INSPECTION REPORT Pursuant to the requirements of the Donald C. Cook Nuclear Plant (CNP) Unit 1 Technical Specification 4.4.5.5.a, Indiana Michigan Power Company is submitting this letter to notify the Nuclear Regulatory Commission of the results of the Unit 1 Cycle 19 steam generator inspection.
The CNP Steam Generator Management Program (SGMP) has been developed to implement the requirements of CNP Technical Specifications (TS).
The overall objective of the SGMP is to ensure structural integrity of the steam generator tubing such that accident-induced and operational leakage is maintained within regulatory limits. The SGMP contains various fundamental elements, which form the basis of the program.
These elements present a balance of prevention, inspection, evaluation, repair and leakage monitoring measures, which interact to ensure that overall steam generator integrity is maintained.
The program revolves around well designed and maintained replacement steam generators that have enhanced design features and materials to resist tube degradation and a thorough inspection program to monitor steam generator conditions.
In December 2000, CNP replaced all four Unit I original steam generators with Babcock & Wilcox Model 5IR steam generators. The replacement steam generators consist of a new lower assembly used in conjunction with refurbished Westinghouse steam domes and Babcock & Wilcox moisture separator units.
Each of the four replacement steam generators received a 100 percent general-purpose (bobbin coil) pre-service examination during the final phases of the steam generator fabrication process in 1999.
This inspection identified no degraded or defective tubes.
The operational baseline was completed at the conclusion of first operating cycle, Cycle 17, in May 2002, for the replacement steam generators.
This.
examination again consisted of a 00 percent full-length bobbin coil examination
-A:C7
U. S. Nuclear Regulatory Commission AEP:NRC:3455 Page 2 of each of the four steam generators. This examination was supplemented by rotating coil inspection of selected bobbin coil indications for diagnostic purposes.
No degraded or defective tubes were identified during this examination and the steam generators were determined to be in degradation category C-I as defined by plant Technical Specification 4.4.5.2, i.e., less then five percent of the total tubes inspected are degraded and none were defective.
Based upon this classification and the associated inspection frequency requirements of Technical Specification 4.4.5.3, which requires the next examination to be completed within not less than 12 nor more than 24 calendar months, the current examination was performed at the conclusion of Cycle 18, in October 2003.
The October 2003 examination consisted of an eddy current inspection of one of the four Unit I steam generators, Steam Generator 14. The inspection was a full-length examination of twenty percent of the steam generator tubes using a bobbin coil probe, which exceeds the twelve percent minimum requirements of TS Table 4.4-2 when one steam generator is being inspected.
In addition, portions of these tubes were examined using a rotating coil for enhanced characterization.
No defective or degraded tubes were identified during these examinations and as a result, no tubes were plugged.
Based upon these results, the CNP Unit 1 steam generators are considered to be in degradation Category C-1. As this inspection completes the second of two consecutive inspections with a C-I result, the Unit I steam generators now fall under the provisions of Technical Specification 4.4.5.3.a which allows the inspection interval to be extended to a maximum of once per 40 months.
Therefore, the next scheduled examination will be performed no later than September 2006.
There are no new commitments in this submittal.
Should you have any questions, please contact Mr. Brian D. Mann, Acting Manager of Regulatory Affairs, at (269) 697-5806.
Sincerely, of Design Engineering and Regulatory Affairs DB/dmb
-I, U. S. Nuclear Regulatory Commission Page 3 AEP:NRC:3455 c:
J. L. Caldwell, NRC Region III K. D. Curry - AEP Ft. Wayne J. T. King, MPSC MDEQ - WHMD/HWRPS NRC Resident Inspector M. A. Shuaibi - NRC Washington DC
U. S. Nuclear Regulatory Commission AEP:NRC:3455 Page 4 bc:
M. J. Finissi D. W. Jenkins J. N. Jensen B. D. Mann M. K. Nazar J. E. Newmiller D. J. Poupard M. K. Scarpello T. K. Woods J. A. Zwolinski