ML13268A492
| ML13268A492 | |
| Person / Time | |
|---|---|
| Site: | Sequoyah  |
| Issue date: | 09/27/2013 |
| From: | Plasse R License Renewal Projects Branch 1 |
| To: | James Shea Tennessee Valley Authority |
| References | |
| TAC MF0481, TAC MF0482 | |
| Download: ML13268A492 (5) | |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 September 27, 2013 Mr. Joe W. Shea Vice President, Nuclear Licensing Tennessee Valley Authority P.O. Box 2000 Soddy-Daisy, TN 37384
SUBJECT:
REQUESTS FOR ADDITIONAL INFORMATION FOR THE REVIEW OF THE SEQUOYAH NUCLEAR PLANT, UNITS 1 AND 2, LICENSE RENEWAL APPLICATION (TAC NOS. MF0481 AND MF0482)- SET 15.
Dear Mr. Shea:
By letter dated January 7, 2013, Tennessee Valley Authority submitted an application pursuant to Title 10 of the Code of Federal Regulations (CFR) Part 54, to renew the operating license DPR-77 and DPR-79 for Sequoyah Nuclear Plant, Units 1 and 2, for review by the U.S. Nuclear Regulatory Commission (NRC) staff. The staff is reviewing the information contained in the license renewal application and has identified, in the enclosure, areas where additional information is needed to complete the review.
These requests for additional information (RAis), outlined in the Enclosure were discussed with Henry Lee, and a mutually agreeable date for the response is within 60 days from the date of this letter. If you have any questions, please contact me at 301-415-1427 or by e-mail at Richard. Plasse@nrc.gov.
Sincerely,
'f/ '27/r!>
~f'\l""f\~ve-t- .S:ltiDL
'ft/{2-Ric ard A. Plasse, f"::~
Projects Branch 1 Division of License Renewal Office of Nuclear Reactor Regulation Docket Nos. 50-327 and 50-328
Enclosure:
Requests for Additional Information cc: Listserv
ML13268A492 OFFICE LA:RPB1 :DLR PM:RPB1 :DLR BC:RPB1 :DLR PM: RPB1 :DLR NAME Y. Edmonds E Sayoc Y Diaz-Sanabria R Plasse DATE 9/27/2013 9/27/2013 9/27/2013 9/27/2013 SEQUOYAH NUCLEAR PLANT, UNITS 1 AND 2 LICENSE RENEWAL APPLICATION REQUESTS FOR ADDITIONAL INFORMATION RAI 4.2-1a (Follow up)
Background:
In the applicant's response to RAI 4.2-1, Parts 1 -4, dated August 9, 2013, the applicant states that the basis for the time-limited aging analysis (TLAAs) on reactor vessel (RV) neutron embrittlement are provided in Westinghouse Technical Report No. WCAP-17539.
In Footnote (f) of Table 3-1 of WCAP-17539, applicant identifies that it did not have any specific unirradiated upper shelf energy (UUSE) data for the fabrication of Unit 1 RV extended beltline circumferential weld W06 from Weld Heat No. 25006. The applicant therefore states that the UUSE value (i.e., 78 ft-lb) for Unit 1 RV weld W06 is based on Charpy impact tests from RV surveillance weld coupons (Surveillance Weld Heat No. 25295) that were removed and tested from Capsule T of the applicant's RV surveillance program.
In Footnote (f) of Table 3-2 of WCAP-17539, the applicant also identifies that it did not have specific UUSE data for the fabrication of RV circumferential welds W06 and W04 for Unit 2, which were fabricated from Weld Heat No. 721858. The applicant therefore states that the UUSE value for these welds (i.e., 78 ft-lb) is based on the limiting UUSE values for all RV beltline and extended beltline welds at Sequoyah Units 1 and 2. As a result, the UUSE value for Unit 2 RV extended beltline circumferential welds W04 and W06 is set to the UUSE value reported for Unit 1 RV extended beltline circumferential weld W06 (Weld Heat No. 25006).
Issue:
The UUSE values reported in the LRA for these RV extended beltline welds do not appear to be based on any NRC-endorsed positions on the establishment of UUSE values, such as those positions in NRC Generic Letter No. 92-01, Revision 1, or in NRC Branch Technical Position 5-3 NUREG 0800, "Standard Review Plan." As a result, the staff needs further demonstration that the UUSE values for Unit 1 RV extended beltline circumferential weld W06 and for Unit 2 RV extended beltline circumferential welds W06 and W04 are sufficiently conservative to ensure that either the upper shelf energy (USE) values for the welds will be maintained above a required end-of-life USE value of 50 ft-lb, in accordance with the USE requirements in 10 CFR Part 50, Appendix G, or that an appropriate equivalent margins analysis (EMA) has been performed for the welds.
Request:
- 1. Provide your basis for why the UUSE value basis that has been reported for Unit 1 RV extended beltline circumferential weld W06 (i.e., 78 ft-lb), as reported in LRA Table 4.2-3 and based on Footnote (f) of Table 3-1 ofWCAP-17539-NP, is considered to be a conservative basis for estimating the UUSE value of the component. In addition, justify how NRC Branch Technical Position 5-3 can be used as the basis for establishing a ENCLOSURE
UUSE value of 78 ft-lbs for this weld when the weld heat identifier (Weld Heat No.
25006) is not represented in any of the surveillance capsules for the RV Surveillance Programs of Sequoyah Unit 1 or Unit 2.
- 2. Identify the NRC regulatory guidance or position that was used to establish a UUSE value of 78 ft-lb for Unit 2 RV extended beltline circumferential welds W06 and W04.
Justify why the basis for establishing a UUSE value of 78 ft-lb for Unit 2 RV extended beltline circumferential welds W06 and W04, as reported in LRA Table 4.2-3 and based on Footnote (f) of Table 3-2 of WCAP-17539-NP, is considered sufficiently conservative and, therefore, a valid basis for the UUSE value, particularly in consideration of the fact that the weld heat identifier (i.e., Weld Heat No. 721858) is not represented in any of the RV Surveillance Programs for the Sequoyah units.
- 3. Given the absence of applicable UUSE data for Unit 1 RV extended beltline weld W06 and for Unit 2 RV extended beltline welds W06 and W04, justify why an EMA would not need to be performed for these welds as part of the LRA in order to demonstrate equivalency with the safety margin requirements in the ASME Code Section XI, Appendix G, as required by 10 CFR Part 50, Appendix G.
Letter to J. Shea from R. Plasse dated September 27, 2013
SUBJECT:
REQUESTS FOR ADDITIONAL INFORMATION FOR THE REVIEW OF THE EQUOYAH NUCLEAR PLANT, UNITS 1 AND 2, LICENSE RENEWAL APPLICATION (TAC NOS. MF0481 AND MF0482)- SET 15.
DISTRIBUTION:
HARD COPY:
DLR RF E-MAIL:
PUBLIC RidsNrrDir Resource RidsNrrDirRpb1 Resource RidsNrrDirRpb2 Resource RidsNrrDirRerb Resource RidsNrrDirRarb Resource RidsNrrDirRasb Resource beth.mizuno@nrc.gov brian. harris@nrc.gov john.pelchat@nrc.gov gena.woodruff@nrc.gov siva.lingam@nrc.gov wesley.deschaine@nrc.gov galen.smith@nrc.gov scott.shaeffer@nrc.gov jeffrey.hamman@nrc.gov craig.kontz@nrc.gov caudle.julian@nrc.gov generette.lloyd@epa.gov gmadkins@tva.gov clwilson@tva.gov hleeO@tva.gov dllundy@tva.gov