ML061940121

E-mail from R. Kuntz, NRC, to D. Chrzanowski, Exelon Byron Unit 2 SG Tube Inspection RAI

ML061940121
Person / Time
Site:	Byron
Issue date:	07/06/2006
From:	Robert Kuntz Office of Nuclear Reactor Regulation
To:	Chrzanowski D Exelon Corp
References
Download: ML061940121 (2)

Text

ýRobert Kuntz - Byron Unit 2 SG Tube Inspection RAIs Page 1,1I From: Robert Kuntz To: david.chrzanowski @exeloncorp.com Date: 07/06/2006 10:57:49 AM

Subject:

Byron Unit 2 SG Tube Inspection RAts The staff is currently reviewing the Bryon Station Unit 2 Fall 2005 steam generator tube inspection results.

To complete its review the staff has the following requests for information (RAI):

1. In the summary of the Nuclear Regulatory Commission's conference call with Byron Unit 2 (the licensee), dated December 7, 2005 (ML053410444), and the licensee letter dated December 5, 2005 (ML060050336), it was reported that SGs 2B and 2C were each found to have one tube with a bulge in or slightly above the tubesheet on the cold-leg side of the SG. The call summary indicated that both the tubes were preventively plugged and stabilized because the voltage of the bulges was considerably larger than the voltage from the hydraulic expansion. However, the licensee letter indicated that the tube in SG 2B was plugged and stabilized while the tube in SG 2C was only plugged. Please discuss whether this tube was plugged or plugged and stabilized.

2. Due to dent and dings being areas of increased stress, discuss the scope and results of any dent and ding exams performed during the end-of-cycle 12 SG tube inspections. Please discuss whether there were any new (service induced) dents/dings identified.

3. In the staff's call summary, it was stated that a secondary-side visual inspection of the steam drum/moisture separator region of SG 2B was scheduled to be performed. Please provide the results of this secondary-side visual inspection.

4. The staff's call summary indicated the foreign object search and retrieval (FOSAR) was in progress for SG 2A and retrieval of the parts found in all SGs was in progress. Please discuss the results of the SG 2A FOSAR. In addition, if any loose parts were left in any of the SGs, discuss whether analyses were performed to ensure that tube integrity would be maintained until the next inspection of these tubes.

Rob Kuntz Project Manager Byron and Braidwood Stations U. S. Nuclear Regulatory Commission NRR/ADRO/DORLJLPL3-2 (301) 415-3733 rfk@nrc.gov

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Subject:

Byron Unit 2 SG Tube Inspection RAIs Creation Date 07/06/2006 10:57:49 AM From: Robert Kuntz Created By: RFK@nrc.gov Recipients Action Date & Time exeloncorp.com Transferred 07/06/2006 10:58:42 AM david.chrzanowski (david.chrzanowski @exeloncom.com)

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