ML070790255
| ML070790255 | |
| Person / Time | |
|---|---|
| Site: | Mcguire, Catawba, McGuire  |
| Issue date: | 03/08/2007 |
| From: | Morris J Duke Energy Carolinas, Duke Power Co |
| To: | Document Control Desk, NRC/NRR/ADRO |
| References | |
| Download: ML070790255 (4) | |
Text
JAMES R. MORRIS m~ Duke Vice President oEnergy Catawba Nuclear Station 4800 Concord Rd. / CNO1 VP York, SC 29745-9635 803 831 4251 803 831 3221 tax
-March 8, 2007 U.S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, D.C. 20555-0001
Subject:
Duke Power Company LLC d/b/a Duke Energy Carolinas, LLC (Duke)
McGuire Nuclear Station, Units 1 and 2 Docket Nos. 50-369 and 50-370 Catawba Nuclear Station, Units I and 2 Docket Nos. 50-413, 50-414 Hydrogen Igniter Backup Power Supply
'This letter is to notify the Nuclear Regulatory Commission (NRC) of changes that Duke Energy Corporation (Duke) intends to implement at the McGuire and Catawba Nuclear Plants that will enhance plant capabilities to mitigate the potential for early containment failure from hydrogen combustion following a severe accident. These changes were discussed with the NRC staff during a January 17, 2007, meeting. The changes address and resolve concerns related to GSI-189, "Susceptibility of Ice Condenser and Mark Ill Containments to Early Failure from Hydrogen Combustion During a Severe Accident.",
As discussed during the January 17, 2007 meeting with the NRC, the Duke proposed enhancement will involve relocating the train 'A" hydrogen igniter loads from its existing power supply to safe shutdown facility (SSF) power supply. The SSF has its own diesel generator that is capable of supplying the additional loads for a train of hydrogen igniters. This proposed enhancement will also include an alternate method of activating the hydrogen igniters from an area other than the control room. In addition, appropriate procedure changes. and training will be conducted as part of the implementation of the enhancement.
Since implementation of the enhancement will require one train of hydrogen igniters to be inoperable for a time longer than allowed by current technical specifications, the enhancement will be implemented during a refueling outage for each unit as described in the attachment to this letter. Duke's commitment for McGuire and Catawba is provided in the attachment to this letter.
www. duke -energy. corn
U.S. Nuclear Regulatory Commission Page 2 March 8, 2007 Inquiries on this matter should be directed to R.D. Hart at (803) 831-3622 or K.L.
Ashe at (704) 875-5715.
Sincerely, Jmes R. Morris
Attachment:
U.S. Nuclear Regulatory Commission Page 3 March 8, 2007 xc (with attachment):
W.D. Travers U.S. Nuclear Regulatory Commission Regional Administrator, Region 11 Atlanta Federal Center 61 Forsyth St., SW, Suite 23T85 Atlanta, GA 30303 J.B. Brady Senior Resident Inspector (MNS)
U.S. Nuclear Regulatory Commission McGuire Nuclear Station A. T. Sabisch Senior Resident Inspector (CNS)
U.S. Nuclear Regulatory Commission Catawba Nuclear Station J.F. Stang NRC Project Manager (MNS and CNS)
U.S. Nuclear Regulatory Commission One White Flint North, Mail Stop 8 H-4A 11555 Rockville Pike Rockville, MID 20852-2738
Attachment Regulatory Commitments The following table identifies the actions committed to by Duke Energy Corporation in this document. Any other actions discussed in this submittal represent intended or planned actions by Duke Energy Corporation. They are described to the Nuclear Regulatory Commission (NRC) for the NRC's information and are not regulatory commitments.
Commitment Date Catawba will install design modifications in Unit 1 and Unit 2 that involve relocating the train 'A",hydrogen igniter loads Ui aur 1
from its existing power supply to safe shutdown facility Unit 10-Jnar1 (SSF) power supply and provide an alternative method of Unt20-Ma 10 00 activating the hydrogen igniters from an area other than Unt2-My3,09 the control room complex.
McGuire will install design modifications in Unit 1 and Unit 2 that involve relocating the train 'A" hydrogen igniter loadsUnt1-Nvme30 from its existing power supply to safe shutdown facility Unt 200Nvebr8 0
(SSF) power supply and provide an alternative method of Unt2008y 1 20 activating the hydrogen igniters from an area other than Unt2-My3,08 the control room complex.
I