ML13198A091

North Anna Power Station Unit 1, Response to Request for Additional Information ASME Section Xl Inservice Inspection Program Relief Request NI-14-LMT-001 - Fourth Interval Period 1 Limited Examinations

ML13198A091
Person / Time
Site:	North Anna
Issue date:	07/12/2013
From:	Grecheck E S Virginia Electric & Power Co (VEPCO)
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
13-393
Download: ML13198A091 (4)

Text

10 CFR 50.55aVIRGINIA ELECTRIC AND POWER COMPANYRICHMOND, VIRGINIA 23261July 12, 2013United States Nuclear Regulatory Commission Serial No. 13-393Attention:

Document Control Desk NAPS/JHL ROWashington, D.C. 20555 Docket No. 50-338License No. NPF-4VIRGINIA ELECTRIC AND POWER COMPANY (DOMINION)

NORTH ANNA POWER STATION UNIT 1RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION ASME SECTION Xl INSERVICE INSPECTION PROGRAMRELIEF REQUEST NI-14-LMT-001

-FOURTH INTERVALPERIOD 1 LIMITED EXAMINATIONS By letter dated November 1, 2012 (Serial No.12-660),

Virginia Electric and PowerCompany (Dominion) submitted a relief request for limited examination coverage (i.e.,less than 90% weld coverage

achieved, due to physical interferences that prohibited attaining full weld coverage) obtained during the inservice inspection (ISI) examinations at North Anna Power Station Unit 1 during the fourth ten-year ISI interval.

Theseexaminations were performed to meet the requirements of the 2004 Edition of ASMESection Xl with No Addenda and the Risk-Informed/Safety-Based Inservice Inspection (RIS B) Program Plan based on Code Case N-716. In an E-mail from Dr. V. Sreenivas, dated March 4, 2013, the NRC requested additional information to complete the reviewof the limited examination relief request.

This information was provided in a letter datedApril 5, 2013 (Serial No.13-141).

In a subsequent E-mail from Dr. V. Sreenivas datedJuly 2, 2013, the NRC requested further clarification of the information provided in theoriginal relief. This information is provided in the attachment to this letter.If you have any questions or require additional information regarding the information provided in the attachment, please contact Mr. Thomas Shaub at (804) 273-2763.

Very truly yours,E. S. GrecheckVice President

-Nuclear Engineering and Development

Attachment:

Response to Request for Additional Information

-ASME Section Xl Inspection Program Relief Request Nl-14-LMT-001 Fourth Interval Period Limited Examinations Commitments made in this letter: None Serial No. 13-393Docket No. 50-338Response to Request for Additional Information Fourth Interval Period 1 ISI Limited Exam Relief RequestPage 2 of 2cc: U.S. Nuclear Regulatory Commission Region IISam Nunn Atlanta Federal Center61 Forsyth Street, SWSuite 23T85Atlanta, Georgia 30303Mr. J. E. Reasor, Jr.Old Dominion Electric Cooperative Innsbrook Corporate Center4201 Dominion Blvd.Suite 300Glen Allen, Virginia 23060NRC Senior Resident Inspector North Anna Power StationMs. K. R. Cotton GrossNRC Project ManagerU. S. Nuclear Regulatory Commission One White Flint NorthMail Stop 0-8 G9A11555 Rockville PikeRockville, Maryland 20852Dr. V. Sreenivas NRC Project ManagerU. S. Nuclear Regulatory Commission One White Flint NorthMail Stop 0-8 G9A11555 Rockville PikeRockville, Maryland 20852 Serial No. 13-393Docket No. 50-338Attachment Response to Request for Additional Information ASME Section XI Inservice Inspection ProgramRelief Request NI-14-LMT-001

-Fourth IntervalPeriod 1 Limited Examinations North Anna Power Station Unit IVirginia Electric and Power Company(Dominion)

Serial No. 13-393Docket No. 50-338Page 1 of 1REQUEST FOR ADDITIONAL INFORMATION (RAI)VIRGINIA ELECTRIC AND POWER COMPANYNORTH ANNA POWER STATION UNIT 1BACKGROUND By letter dated November 1, 2012 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML12319A278),

Virginia Electric and Power Company(Dominion) submitted Relief Request (RR) Nl-14-LMT-001 for U.S. Nuclear Regulatory Commission (NRC) review and approval.

Dominion requested relief from certainrequirements of the American Society of Mechanical Engineers Boiler and PressureVessel Code (ASME Code), Section Xl, specifically related to examination coverage.

RR Nl-14-LMT-001 is applicable to the fourth 10-year inservice inspection (ISI) intervalfor the North Anna Power Station (NAPS) Unit 1, which commenced on May 1, 2009and will end on April 30, 2019. On March 4, 2013, the NRC sent Dominion a request foradditional information (RAI) concerning this relief request.

The response to the RAI wasprovided on April 5, 2013. In a subsequent e-mail dated July 2, 2013, the NRCrequested further clarification of the information provided in the original relief. The NRCRAI and the Dominion responses are provided below.NRC INFORMATION REQUESTNRC QuestionThe relief request stated that the volumetric examination identified indications in Welds8 (12"-SI-67) and SW-12 (32"-SHP-58) that were determined to be root geometry.

Please provide the detail:* How did the licensee determine that these indications were root geometry?

• Were these root geometries also detected by the previous examinations in thesewelds?Dominion ResponseBeam plots, profiles, along with UT signals were used to characterize the geometrical condition of Weld SW-12 on line 32"-SHP-58.

The indications were evaluated using theIndication Classification guidance of the Appendix VIII qualified procedure utilized forthe examination.

This weld had been examined three previous times with intermittent geometry noted in previous reports.Beam plots, profiles, along with UT signals were also used to characterize thegeometrical condition of Weld 8 on line 12"-SI-67.

The indications were evaluated usingthe Indication Classification guidance of the appendix VIII qualified procedure utilized forthe examination.

This location was not previously examined.