ML13022A088

Response to Request for Additional Information (RAI 19) Regarding Confirmatory Action Letter Response (TAC No. Me 9727)

ML13022A088
Person / Time
Site:	San Onofre
Issue date:	01/16/2013
From:	St.Onge R Southern California Edison Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
TAC ME9727
Download: ML13022A088 (4)

Text

\\V SOUTHERN CALIFORNIA Richard J. St. Onge Director, Nuclear Regulatory Affairs and EDISON Emergency Planning An EDISON INTERNATIONAL Company January 16, 2013 10 CFR 50.4 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001

Subject:

Docket No. 50-361 Response to Request for Additional Information (RAI 19)

Regarding Confirmatory Action Letter Response (TAC No. ME 9727)

San Onofre Nuclear Generating Station, Unit 2

References:

1. Letter from Mr. Elmo E. Collins (USNRC) to Mr. Peter T. Dietrich (SCE), dated March 27, 2012, Confirmatory Action Letter 4-12-001, San Onofre Nuclear Generating Station, Units 2 and 3, Commitments to Address Steam Generator Tube Degradation

2. Letter from Mr. Peter T. Dietrich (SCE) to Mr. Elmo E. Collins (USNRC), dated October 3, 2012, Confirmatory Action Letter - Actions to Address Steam Generator Tube Degradation, San Onofre Nuclear Generating Station, Unit 2

3. Letter from Mr. James R. Hall (USNRC) to Mr. Peter T. Dietrich (SCE), dated December 26, 2012, Request for Additional Information Regarding Response to Confirmatory Action Letter, San Onofre Nuclear Generating Station, Unit 2

Dear Sir or Madam,

On March 27, 2012, the Nuclear Regulatory Commission (NRC) issued a Confirmatory Action Letter (CAL) (Reference 1) to Southern California Edison (SCE) describing actions that the NRC and SCE agreed would be completed to address issues identified in the steam generator tubes of San Onofre Nuclear Generating Station (SONGS) Units 2 and 3. In a letter to the NRC dated October 3, 2012 (Reference 2), SCE reported completion of the Unit 2 CAL actions and included a Return to Service Report (RTSR) that provided details of their completion.

By letter dated December 26, 2012 (Reference 3), the NRC issued Requests for Additional Information (RAIs) regarding the CAL response. Enclosure 1 of this letter provides the response to RAI 19.

P.O. Box 128 San Clemente, CA 92672

Document Control Desk January 16, 2013 There are no new regulatory commitments contained in this letter. If you have any questions or require additional information, please call me at (949) 368-6240.

Sincerely,

Enclosures:

1. Response to RAI 19 cc: E. E. Collins, Regional Administrator, NRC Region IV J. R. Hall, NRC Project Manager, SONGS Units 2 and 3 G. G. Warnick, NRC Senior Resident Inspector, SONGS Units 2 and 3 R. E. Lantz, Branch Chief, Division of Reactor Projects, NRC Region IV

ENCLOSURE 1 SOUTHERN CALIFORNIA EDISON RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION REGARDING RESPONSE TO CONFIRMATORY ACTION LETTER DOCKET NO. 50-361 TAC NO. ME 9727 Response to RAI 19 Page 1

RAI 19

Reference 1, Section 11.2, page 52 - Provide additional details on how the GE Smart Signal System will be used in the context of tube-to-tube wear and/or the circumstances associated with tube-to-tube wear. What information/data will the system be evaluating? For what purpose?

RESPONSE

As stated in the RAI Reference 1, Section 11.2, GE Smart Signal TM will be used as "an analytic tool that aids in diagnosis of equipment conditions. The tool will be used to analyze historical plant process data from the Unit 2 steam generators (SGs) following the inspection interval."

GE Smart Signal TM will be used as a backward looking tool to assist in the investigation of any additional tube-to-tube wear identified during the mid-cycle inspection. GE Smart Signal TM is not included as a Defense in Depth measure in section 9 of RAI Reference 1.

GE Smart Signal TM is a software program used to trend and monitor variances in plant equipment (such as pressures, temperatures, flowrate, speed, feedwater pump and turbine vibration). GE Smart Signal TM will be monitoring the following equipment:

1. Unit 2 Steam Generators

2. Unit 2 Main Feedwater Pumps

3. Unit 2 Main Feedwater Turbines Page 2