ML020880630

Plans for Repair of Recirculating Cooling Water (Rc) System Expansion Joints

ML020880630
Person / Time
Site:	Catawba
Issue date:	03/20/2002
From:	Gordon Peterson Duke Power Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
IR-01-002
Download: ML020880630 (3)

Text

SDuke Duke Power a Power 4800 Concord Rd.

York, SC 29710 A DueEne C a (803) 831-4251 OFFICE (803) 831-3221 FAX Gary R. Peterson grpeters@duke-energy.com Vice President Catawba Nuclear Station March 20, 2002 U. S. Nuclear Regulatory Commission Document Control Desk Washington, DC 20555-0001

Subject:

Duke Energy Corporation Catawba Nuclear Station Unit 1,2 USNRC License NPF No. 35 and NPF No. 52 USNRC Docket No. 50-413 and 50-414 Plans for Repair of Recirculating Cooling Water (RC) System Expansion Joints

Reference:

Letter from USNRC to Duke Energy Corporation, Catawba Nuclear Station - NRC Inspection Report 50-413/01-02, 50-414/01-02, February 23, 2001.

Gentlemen:

The purpose of this letter is to outline the plans for repair of the Recirculating Cooling Water (RC) Expansion Joints. This response is in regards to issues discussed during the exit meeting for NRC Inspection 50-413/01-02, 50-414/01-02 on January 26, 2001. These issues, which were not findings, were noted in section 4 of the inspection report. The inspectors were concerned about stress cracking and age-related deterioration of the RC system rubber expansion joints. On each unit there are eight 10-foot diameter expansion joints and two 30-inch diameter expansion joints of concern. At the time of the exit meeting the licensee's plans for repair or replacement of these expansion joints was not complete. However, recent budget and planning meetings have resulted in a clearer picture of the repair plans.

At the end of the last Unit 2 Outage one of the original 10-foot joints on the 2AI Waterbox developed a small leak. This was repaired using an additional internal "Hydra-Tight" seal that was installed by Universal Utility Services. During the outage an inspection of the joint and similar joints was performed. An engineering calculation (CNC-1206.0006-0001) was developed to

U. S. Nuclear Regulatory Commission March 20, 2002 Page 2 determine the acceptability of continued operation of the RC system with the original rubber expansion joints installed. The calculation concluded that the continued structural integrity of the joints could be based on leakage with a fairly high degree of certainty. If a leak were to develop that is through wall, this would be considered a sign that the structural strength of the joint had diminished. The joint would then be repaired at the next available opportunity.

Earlier this year a decision was made to repair the eight 10 foot expansion joints and two 30-inch joints on Unit 1 during the next outage (lEOCI3), currently scheduled for April 27, 2002. The current plan is to attempt to repair all ten seals.

However, the roughness of the coatings on the inside of the RC piping could effect the ability of the Hydra-Tight seals to form a watertight seal. The time required to prepare these surfaces could limit the number of seals completed during the upcoming outage, which is currently scheduled for 18.5 days.

Plans to repair the remaining nine RC expansion joints on Unit 2 are included in the station's long-range plan. However, this repair has not been approved for a particular outage since the budget cycle does not extend to that time frame at present. The next Unit 2 outage is scheduled for March 2003.

The intent of this letter is only to inform the Commission on the current plans for RC expansion joint repair at the Catawba site. This document contains no new commitments.

For additional information contact Tony Jackson at 803-831-3742.

Sinerly, GaryR Peterson APJ/apj

U. S. Nuclear Regulatory Commission March 20, 2002 Page 3 xc:

L. A. Reyes, Regional Administrator, Region II U. S. Nuclear Regulatory Commission Atlanta Federal Center 61 Forsyth Street, SW, Suite 23T85 Atlanta, GA 30303 C. P. Patel, NRR Senior Project Manager (CNS)

U. S. Nuclear Regulatory Commission Mail Stop 0-8 H12 Washington, DC 20555-0001 R.C. Haag, Chief Reactor Projects Branch 1 U. S. Nuclear Regulatory Commission RGN-II/DRP/RPB5 Atlanta Federal Center 61 Forsyth Street Atlanta, GA 30303 D. J. Roberts, Senior Resident Inspector (CNS)

U. S. Nuclear Regulatory Commission Catawba Nuclear Station R. E. Carroll, Jr., Region II U. S. Nuclear Regulatory Commission DRP/RPBI Atlanta Federal Center 61 Forsyth Street Atlanta, GA 30303