ML060530405

Implementation of Degraded Voltage Protection Backfit

ML060530405
Person / Time
Site:	Cook
Issue date:	02/08/2006
From:	Jensen J Indiana Michigan Power Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
AEP:NRC:6321, TAC MC5735, TAC MC5736
Download: ML060530405 (2)

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Indiana Michigan Power Company Nuclear Generation Group INDIANA One Cook Place MICHIGAN Bridgman, MI 49106 POWER aep.com February 8, 2006 AEP:NRC:6321 10 CFR 50.109 Docket Nos.: 50-315 50-316 U. S. Nuclear Regulatory Commission ATTN: Docuament Control Desk Mail Stop O-P1-17 Washington., DC 20555-0001 Donald C. Cook Nuclear Plant Units 1 and 2 Implementation of Degracled Voltage Protection Backfit

References:

1) Letter from C. Haney, U. S. Nuclear Regulatory Commission (NRC), to M. K. Nazar, Indiana Michigan Power Company (I&M), 'Donald C. Cook Nuclear Plant, Units 1 and 2 - Imposition of Facility-Specific Backfit Re:

Degraded Voltage Protection System (TAC Nos. MC5735 and 5736)," dated November 9, 2005, ML050680057.

2) Letter from J. N. Jensen, I&M, to NRC, 'Degraded Voltage Protection at Donald C. Cook Nuclear Plant," dated December 10, 2004, ML043500015.

By Reference 1, the Nuclear Regulatory Commission (NRC) informed Indiana Michigan Power Company (I&M) of a proposed backfit in accordance with 10 CFR 50.109. The proposed backfit consists of modifying the design of Donald C. Cook Nuclear Plant Units 1 and 2 such that automatic degraded voltage protection is not bypassed during normal operation. The NRC stated in Reference 1 that I&M may choose to implement the backfit or appeal it.

I&M has chosen to implement the backfit. In Reference 1, the NRC stated that, if I&M chose to implement the backfit, implementation should be accomplished on a schedule negotiated with the NRC staff in accordance with NRC Management Directive (MD) 8.4, Paragraph (I1)(B)(9). MD 8.4, Paragraph (]I)(B)(9) states that scheduling criteria should include the importance of the backfit relative to other safety or security-related activities under way, such as planned construction or maintenance that will allow the facility to maintain the schedule of construction or continue operations.

I&M is currently evaluating options for implementing the backfit. I&M expects that implementation of the backfit will require significant planning and expenditure of resources. I&M anticipates that fylt

U. S. Nuclear Regulatory Commission AEP:NRC:6321 Page 2 up to two operating cycles will be needed for each unit to complete implementation of the backfit. I&M intends to meet with members of the NRC staff to discuss technical and schedular considerations, and establish a mutually acceptable date by which implementation of the backfit will be complete.

As described in Section 3.0 of Attachment 1 to Reference 2, I&M considers the existing degraded voltage protection system design adequate to assure plant safety. Additionally, I&M concludes that acceptance of this backfit does not result in the units being in noncompliance with the associated technical specifications. However, I&M has enhanced the level of plant safety by changing plant operating procedures to include additional actions to be taken in response to a sustained degraded voltage condition. The procedure changes have been implemented and are expected to remain in effect until the backfit modifications are completed.

This letter contains no new regulatory commitments. Should you have any questions, please contact Mr. Michael K. Scarpello, Regulatory Affairs Supervisor, at (269) 466-2649.

Sincerely, h N. Jensen Site Vice President JW/rdw C: J. L. Caldwell, NRC Region III K. D. Curry, Ft. Wayne AEP J. T. King, MPSC MDEQ - WHMD/RPMWS NRC Resident Inspector P. S. Tam, NRC Washington, DC