NL-15-0341, Clarification of Response to Request for Additional Information on Spring 2013 Steam Generator Tube Inspections
| ML15054A536 | |
| Person / Time | |
|---|---|
| Site: | Vogtle  |
| Issue date: | 02/23/2015 |
| From: | Pierce C Southern Co, Southern Nuclear Operating Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| NL-15-0341, TAC MF4288 | |
| Download: ML15054A536 (4) | |
Text
Charles R. Pierce Regulatory Affairs Director February 23, 201 5 Docket Nos.: 50-425 Southern Nuclear Operating Company, Inc.
40 Inverness Center Parkway Post Office Box 1295 Birmingham, AL 35242 Tel 205.992.7872 Fax 205.992.7601 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D. C. 20555-0001 Vogtle Electric Generating Plant - Unit 2 SOUTHERN A COMPANY NL-1 5-0341 Clarification of Response to "Request for Additional Information on Spring 201 3 Steam Generator Tube Inspections (TAC No. MF4288)"
Ladies and Gentlemen:
By letters dated July 2, 201 3 (Agencywide Documents Access and Management System (ADAMS) Accession Number ML13184A269) and September 26, 201 3 (ADAMS Accession Number ML14170A021 ), Southern Nuclear Operating Company, Inc. (SNC) submitted information summarizing the results of the spring 201 3 steam generator (SG) tube inspections performed at Vogtle Electric Generating Plant, Unit 2. These inspections were performed during refueling outage 1 6 (RFO 1 6). In a letter dated April 25, 2013 (ADAMS Accession Number ML13112A225), the U.S. Nuclear Regulatory Commission (NRC) staff summarized two conference calls that were held with the licensee during RFO 1 6.
The NRC issued a request for additional information (RAI) via a letter dated November 1 3, 201 4 (ADAMS Accession Number ML14314A878), which was answered by SNC via letter dated January 12, 201 5 (ADAMS Accession Number ML15013A023). Following receipt of this letter, the NRC and SNC participated in a clarification call on February 2, 201 5. Additional information was requested from SNC to further explain the response to RAI question number five in the January 12, 201 5 letter. The enclosure to this letter contains the SNC response to that request.
This letter contains no NRC commitments. If you have any questions, please contact Ken McElroy at (205) 992-7369.
Respectfully s"ed, c.11!
C. R. Pierce Regulatory Affairs Director CRP/EGA
U. S. Nuclear Regulatory Commission NL-1 5-0341 Page 2
Enclosure:
SNC Response to Request for Additional Information Question Number 5 cc:
Southern Nuclear Operating Company Mr. S. E. Kuczynski, Chairman, President & CEO Mr. D. G. Bast, Executive Vice President & Chief Nuclear Officer Mr. D. R. Madison, Vice President - Fleet Operations Mr. M. D. Meier, Vice President - Regulatory Affairs Mr. B. K. Taber, Vice President - Vogtle 1 & 2 Mr. B. J. Adams, Vice President - Engineering Mr. G. W. Gunn, Regulatory Affairs Manager - Vogtle 1 & 2 RType: CVC7000 U. S. Nuclear Regulatory Commission Mr. V. M. McCree, Regional Administrator Mr. R. E. Martin, NRR Senior Project Manager - Vogtle 1 & 2 Mr. L. M. Cain, Senior Resident Inspector - Vogtle 1 & 2 State of Georgia Mr. J. H. Turner, Environmental Director - Protection Division
Vogtle Electric Generating Plant - Unit 2 Clarification of Response to "Request for Additional Information on Spring 201 3 Steam Generator Tube Inspections (TAC No. MF4288)"
Enclosure SNC Response to Request for Additional Information Question Number 5
Enclosure to NL-1 5-0341 SNC Response to RAI 5 NRC Question 5 A "historical" tube wear indication in SG 4 was reported. In reviewing the prior inspection report submitted to the NRC, no reference was made to this indication. Please confirm that this indication was detected in the prior inspection and that all indications are being reported.
SNC Response to RAI 5 in the January 12, 2015 letter Tube SG4 R1 2C57 was previously identified as a volumetric indication associated with Mechanical Wear and Wall Loss from Secondary Side Cleaning activities reported in the Unit 2 Refueling Outage 1 3 inspection report (Reference ADAMS Accession Number ML090990606).
This indication has been re-categorized as loose part wear based on evaluation of location and eddy current signal character in the Unit 2 Refueling Outage 1 6. No progression of growth has been identified and no foreign objects have been associated with this indication. Indications are reported as they are identified. The indication associated with SG4 R12C57 was identified prior to Unit 2 Refueling Outage 1 5 (2R15), and discussion of this tube indication was not included in the 2R1 5 inspection report.
Additional Information for SNC Response to RAI 5 The review of previous inspection reports and inspection results for Vogtle Unit 2 identified additional tubes that should have been included in the Vogtle Unit 2 Refueling Outage 1 5 report.
These indications were identified in Vogtle 2 Refueling Outage 1 3 and reported in the 2R1 3 inspection report (ML090990606). These indications were confirmed in the Vogtle Unit 2 Refueling Outage 1 5 inspection with no progression of growth. Table 1 listed below contains the additional tubes that were not reported in the Vogtle Unit 2 Refueling Outage 1 5 report for Tube Wear and Wall Loss from the Secondary Side Cleaning Processes.
Table 1: Vogtle 2 Tube Wear and Wall Loss from Secondary Side Cleaning for 2R15 SG Row Col Volts lnd 1
1 46 0.22 PCT 1
1 78 0.21 PCT 1
1 78 0.1 3 PCT 4
42 93 0.29 PCT Definitions:
TSC - Tubesheet region on Coldleg side TSH - Tubesheet region on Hotleg side lnd - Indication
%TWO-Percent Through wall Depth Locn - Location PCT - Percent Volumetric Degradation E-1
%TWO Locn 1 8 TSH+1 0.29 1 7 TSH+9.63 1 2 TSH+1 1.44 24 TSC+0.99