ML032790018

Letter, Evaluation of Steam Generator Tube Inspection Report, Ninth Refueling Outage, April 2002

ML032790018
Person / Time
Site:	Braidwood
Issue date:	10/28/2003
From:	Mahesh Chawla NRC/NRR/DLPM/LPD3
To:	Skolds J Exelon Generation Co
Chawla M, 415-8371, NRR/DLPM
References
TAC MB8476
Download: ML032790018 (5)

Text

October 28, 2003 Mr. John L. Skolds, President Exelon Nuclear Exelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555

SUBJECT:

EVALUATION OF STEAM GENERATOR TUBE INSPECTION REPORT BRAIDWOOD STATION, UNIT 2, NINTH REFUELING OUTAGE, APRIL 2002 (TAC NO. MB8476)

Dear Mr. Skolds:

By letters dated May 10, 2002 (ML021480394) and April 9, 2003 (ML031110379), Exelon Generation Company, the licensee for Braidwood Station, submitted reports from the steam generator (SG) inspections performed in Unit 2 during the ninth refueling outage in April 2002.

These reports were submitted in accordance with Braidwood Station technical specifications 5.6.9.a and 5.6.9.b. After initial review, the NRC staff developed a set of questions and the requested information was submitted by the licensee in a letter dated July 29, 2003 (ML032200254). The NRCs evaluation of the inspection results is summarized below.

Braidwood Station, Unit 2 has four Model D-5 recirculating steam generators that began operation in 1988. Each steam generator contains 4,570 thermally treated Alloy 600 tubes.

Each tube has a nominal outside diameter of 0.750 inches and nominal thickness of 0.043 inches. The tubes were hydraulically expanded at both ends for the full length of the tubesheet, and they are supported by stainless steel support plates with quatrefoil-shaped holes. The U-bend portion is supported by four chromium-plated Alloy 600 anti-vibration bars (AVBs).

During the 2002 outage, the licensee performed bobbin coil inspections on 100 percent of the tubes in SG 2A. Rotating probe inspections were performed at some of the locations with bobbin coil indications. No eddy current inspections were performed in SGs 2B, 2C, or 2D. As a result of these inspections, two tubes were plugged due to wear at anti-vibration bars.

Anti-vibration bar wear was the only degradation mode reported from the inspection.

Foreign object search and retrieval (FOSAR) was performed on the secondary side in all four steam generators. The FOSAR inspections revealed a total of six objects in SGs 2B (2 objects), 2C (1 object), and 2D (3 objects), four of which were removed. The licensee found no indications of degradation associated with foreign objects. Additional details regarding these loose parts can be found in the licensees July 29, 2003 letter.

J. Skolds Based on a review of the information provided by the licensee, the NRC staff concludes that the information the licensee was required to submit according to their technical specifications was provided and that no additional follow-up is required at this time.

Sincerely,

/RA/

Mahesh Chawla, Project Manager, Section 2 Project Directorate III Division of Licensing Project Management Office of Nuclear Reactor Regulation Docket Nos.: STN 50-456 and STN 50-457 cc w/encls: See next page

J. Skolds Based on a review of the information provided by the licensee, the NRC staff concludes that the information the licensee was required to submit according to their technical specifications was provided and that no additional follow-up is required at this time.

Sincerely,

/RA/

Mahesh Chawla, Project Manager, Section 2 Project Directorate III Division of Licensing Project Management Office of Nuclear Reactor Regulation Docket Nos.: STN 50-456 and STN 50-457 cc w/encls: See next page DISTRIBUTION:

PUBLIC PD3-2 r/f WRuland PCoates AMendiola GHill (4)

MChawla AStone, RIII GMakar WBeckner MMurphy LLund OGC ACRS ADAMS Accession Number: ML032790018 OFFICE PM:LPD3-2 LA:LPD3-2 C:EMCB:DE TL:LPD3-2 SC:LPD3-2 NAME MChawla PCoates LLund* DPickett AMendiola DATE 108/03 10/8/03 9/22/03 10/8/03 10/28/03 OFFICIAL RECORD COPY

Braidwood Station Units 1 and 2 cc:

Regional Administrator, Region III Illinois Emergency Management U.S. Nuclear Regulatory Commission Agency 801 Warrenville Road Division of Disaster Assistance &

Lisle, IL 60532-4351 Preparedness 110 East Adams Street Document Control Desk - Licensing Springfield, IL 62701-1109 Exelon Generation Company, LLC 4300 Winfield Road Chairman Warrenville, IL 60555 Will County Board of Supervisors Will County Board Courthouse Ms. C. Sue Hauser, Project Manager Joliet, IL 60434 Westinghouse Electric Corporation Energy Systems Business Unit Attorney General Post Office Box 355 500 S. Second Street Pittsburgh, PA 15230 Springfield, IL 62701 Joseph Gallo George L. Edgar Gallo & Ross Morgan, Lewis and Bockius 1025 Connecticut Ave., NW, Suite 1014 1800 M Street, NW Washington, DC 20036 Washington, DC 20036-5869 Ms. Bridget Little Rorem Braidwood Station Plant Manager Appleseed Coordinator Exelon Generation Company, LLC 117 N. Linden Street 35100 S. Rt. 53, Suite 84 Essex, IL 60935 Braceville, IL 60407-9619 Howard A. Learner Site Vice President - Braidwood Environmental Law and Policy Exelon Generation Company, LLC Center of the Midwest 35100 S. Rt. 53, Suite 84 35 East Wacker Dr., Suite 1300 Chicago, IL 60601-2110 Braceville, IL 60407-9619 U.S. Nuclear Regulatory Commission Senior Vice President, Nuclear Braidwood Resident Inspectors Office Services 35100 S. Rt. 53, Suite 79 Exelon Generation Company, LLC Braceville, IL 60407 4300 Winfield Road Warrenville, IL 60555 Ms. Lorraine Creek RR 1, Box 182 Vice President - Operations Support Manteno, IL 60950 Exelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555 Chairman, Ogle County Board Post Office Box 357 Oregon, IL 61061

J. Skolds Braidwood Station Units 1 and 2 Regulatory Assurance Manager - Braidwood Exelon Generation Company, LLC 35100 S. Rt. 53, Suite 84 Braceville, IL 60407-9619 Chief Operating Officer Exelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555 Director Licensing Exelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555 Senior Counsel, Nuclear Exelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555 Vice President - Licensing and Regulatory Affairs Exelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555 Manager Licensing - Braidwood and Byron Exelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555