ML15169A251

NRR E-mail Capture - Request for Additional Information Regarding Byron Station, Unit 2, Steam Generator Tube Inspection Report for Refueling Outage 18

ML15169A251
Person / Time
Site:	Byron
Issue date:	06/18/2015
From:	Joel Wiebe Plant Licensing Branch III
To:	Spitzer D Exelon Corp
References
Download: ML15169A251 (2)

Text

NRR-PMDAPEm Resource From: Wiebe, Joel Sent: Thursday, June 18, 2015 10:55 AM To: Doug Spitzer

Subject:

Request for Additional Information Regarding Byron Station, Unit 2, Steam Generator Tube Inspection Report for Refueling Outage 18

Doug, By letter dated February 20, 2015 (Agencywide Documents Access and Management System Accession No. ML15051A312), Exelon Generation Co., LLC (the licensee) submitted information summarizing the results of the fall 2014 steam generator tube inspections at Byron Station, Unit 2. These inspections were performed during refueling outage 18 (RFO 18). A response is requested within 30 days.

In order to complete its review, the U.S. Nuclear Regulatory Commission (NRC) staff requests the following additional information:

1. Discuss the results of the Dent/Ding Special Interest Scope inspections. Were these inspections related to the denting phenomenon observed during RFO 16? If so, were attempts made to obtain the orientation of the dents? Also discuss whether the condition is progressing.

2. Was any degradation or leakage observed during the plug visual inspections? If so, please describe.

3. Note 1 to the anti-vibration bar (AVB) wear summary table on page 7 indicates that there is a 15 percent through-wall (TW) reporting criteria for AVB wear. Provide clarification of the 15 percent TW reporting criteria. For example, is the 15 percent TW criteria the level at which an eddy current analyst will report/record an indication or is this the depth at which indications are reported to the NRC? If the latter, confirm that all service induced indications, regardless of depth, have been reported to the NRC per TS 5.6.9.d.

4. There is a similar Note 1 in the tube support plate (TSP) wear summary table on page 7. Provide clarification as requested in 3, above.

5. At the 07C TSP, both flat and tapered wear have been reported. Confirm that the shape of the wear is confirmed by a rotating probe or array probe. Also, discuss why there is a difference in the shape of wear at the 07C TSP. Do all the quatrefoil openings of the 07C TSP have the same shape?

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Hearing Identifier: NRR_PMDA Email Number: 2157 Mail Envelope Properties (Joel.Wiebe@nrc.gov20150618105500)

Subject:

Request for Additional Information Regarding Byron Station, Unit 2, Steam Generator Tube Inspection Report for Refueling Outage 18 Sent Date: 6/18/2015 10:55:11 AM Received Date: 6/18/2015 10:55:00 AM From: Wiebe, Joel Created By: Joel.Wiebe@nrc.gov Recipients:

"Doug Spitzer" <Douglas.Spitzer@exeloncorp.com>

Tracking Status: None Post Office:

Files Size Date & Time MESSAGE 1935 6/18/2015 10:55:00 AM Options Priority: Standard Return Notification: No Reply Requested: No Sensitivity: Normal Expiration Date:

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