ML070610328
| ML070610328 | |
| Person / Time | |
|---|---|
| Site: | Oconee  |
| Issue date: | 02/14/2007 |
| From: | Brandi Hamilton Duke Energy Carolinas, Duke Power Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| GL-96-006 | |
| Download: ML070610328 (3) | |
Text
Duke BRUCE H HAMILTON F_-2ýDukeVice President 6 Energy Oconee Nuclear Station Duke Energy Corporation ON01 VP / 7800 Rochester Highway Seneca, SC 29672 864 885 3487 864 885 4208 fax bhhamilton@duke-energy. com February 14, 2007 U.S. Nuclear Regulatory Commission Document Control Desk Washington, D.C. 20555
Subject:
Duke Power Company LLC d/b/a Duke Energy Carolinas, LLC Oconee Nuclear Station Docket Nos. 50-269, 50-270, 50-287 Generic Letter 96-06: Assurance of Equipment Operability and Containment Integrity During Design-Basis Conditions - Waterhammers -
Supplemental Information Regarding Modification Schedules Generic Letter (GL) 96-06, "Assurance of Equipment Operability and Containment Integrity During Design Basis Conditions" was issued on September 30, 1996. GL 96-06 requested licensees to determine if containment air cooler cooling water systems are susceptible to either waterhammer or two-phase flow conditions during postulated accident conditions and to determine if piping systems that penetrate containment are susceptible to thermal expansion of fluid that could lead to overpressurization of piping.
Duke Energy Carolinas (Duke) responded to the GL 96-06 in submittals to the NRC dated October 29, 1996, January 28, 1997, April 15, 1997, June 30, 1997, August 1, 1997, May 28, 1998, September 22, 1998, December 17, 1998, September 30, 2002, March 24, 2003, September 29, 2003, and May 10, 2006.
In the September 30, 2002 letter, Duke indicated that although the required systems remained operable, certain code allowables associated with the piping and the present piping support/restraint system would be exceeded without implementation of modifications to reduce the magnitudes of waterhammers. The letter also provided the conceptual scope of the proposed modifications and indicated that the schedules to complete the additional modifications would be provided when the plans and schedule for the modifications were developed.
Duke originally provided the schedule to implement the design modifications in a letter dated September 29, 2003. These dates were later revised in a letter dated May 10, 2006. The change in implementation dates allowed for NRC review and approval of a submittal that was deemed necessary prior to implementation.
www. duke-energy. corn
US NRC Document Control Desk February 14, 2007 Page 2 Oconee has completed modifications to address thermally induced overpressurization of Reactor Building Penetration Piping.
In addition, two large modifications were planned to the Low Pressure Service Water System to address the waterhammers described in GL 96-06. One involves the piping associated with the Reactor Building Auxiliary Coolers (RBACs), while the other involves piping and valves associated with the Reactor Building Cooling Units (RBCUs). The modifications associated with the RBACs have been completed on all three units. This letter addresses the commitment dates relative to the modifications pertaining to RBCUs. Due to the additional time necessary to support the analysis and LAR submittal, the modification completion schedule has changed as follows:.
Unit End-of Cycle Outage No.
Approximate Date 2
23 Fall 2008 3
24 Spring 2009 1
25 Fall 2009 Please address any questions to Reene' Gambrell at 864-885-3364.
Very truly yours, B. H. Hamilton, Site Vice President Oconee Nuclear Station cc:
Mr. W. D. Travers, Regional Administrator U. S. Nuclear Regulatory Commission, Region II Atlanta Federal Center 61 Forsyth St., SW, Suite 23T85 Atlanta, Georgia 30303 Mr. L. Olshan, Project Manager Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Mail Stop 0-14 H25 Washington, D.C. 20555 Mr. D. W. Rich Senior Resident Inspector Oconee Nuclear Site
US NRC Document Control Desk February 14, 2007 Page 3 bcc:
Lisa F. Vaughn Graham Davenport Ken Ashe-MNS Randy D. Hart - CNS Robert L. Gill -NAID Reene V. Gambrell Beau Abellana Steve D. Capps Patsy Earnhardt Elizabeth S. Durham Lenny Azzarello BWOG Tech Spec Committee (5)
NSRB, EC05N ELL, EC050 ONS Document Management (OS-293)
Commitments