ML13316C078

Arkansas Nuclear One - Unit 2, Response to Request for Additional Information Related to Relief Request ANO2-ISI-004

ML13316C078
Person / Time
Site:	Arkansas Nuclear
Issue date:	11/11/2013
From:	Stephanie Pyle Entergy Operations
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
2CAN111305, ANO2-ISI-004, TAC MC9768, TAC MF2319
Download: ML13316C078 (5)

Text

2CAN111305November 11, 2013U.S. Nuclear Regulatory CommissionAttn: Document Control DeskWashington, DC 20555

Subject:

Response to Request for Additional InformationRelated to Relief Request ANO2-ISI-004Arkansas Nuclear One - Unit 2Docket No. 50-368License No. NPF-6

References:

1. Entergy letter dated April 24, 2013, "Additional Reactor Vessel ClosureHead Weld Request for Alternative ANO2-ISI-004, ProposedAlternative to Extend the Third 10-Year Inservice Inspection Interval forReactor Vessel Weld Examinations" (2CAN041303) (ML13115A015)2. Letter from NRC to Mr. Gordon Bischoff, Manager, Owner's GroupProgram Management Office, Final Safety Evaluation ofPressurized Water Reactor Owners Group (PWROG) TopicalReport (TR) WCAP-16168-NP, Revision 2, "Risk-InformedExtension of the Reactor Vessel In-Service Inspection Interval"(TAC No. MC9768), dated May 8, 2008 (ML081060051)3. NRC email dated October 9, 2013, "RAI on Request for Relief No.ANO2-ISI-004 (TAC No. MF2319)" (ML13282A360)

Dear Sir or Madam:

Entergy Operations, Inc. (Entergy) requested NRC's approval of an alternative to therequirements of the American Society of Mechanical Engineers Boiler and Pressure Code,Section XI, paragraph IWB-2412, Inspection Program B, for Arkansas Nuclear One, Unit 2(ANO-2) in Reference 1. In particular the requirement that volumetric examination of essentially100% of the reactor vessel pressure retaining Examination Category B-A and B-D welds beperformed once each ten-year inservice inspection (ISI) interval. The alternative was to extendthe examination frequency to once every 20 years. The request was based upon themethodology outlined in Reference 2.On reviewing the submittal, the NRC staff requested additional information (RAI) to continue thereview and issued Reference 3. Attached is Entergy's response to the request.Entergy Operations, Inc.1448 S.R. 333Russellville, AR 72802Tel 479-858-4704Stephenie L. PyleManager, LicensingArkansas Nuclear One 2CAN111305Page 2 of 2This submittal contains no regulatory commitments.Should you have any questions, please contact me.Sincerely,Original signed by Stephenie L. PyleSLP/rwc

Attachment:

Response to Request for Additional Information Regarding Request forAlternative ANO2-ISI-004 Proposed Alternative to Extend the Third 10-YearInservice Inspection Interval for Reactor Vessel Weld Examinationscc: Mr. Marc L. DapasRegional AdministratorU. S. Nuclear Regulatory CommissionRegion IV1600 East Lamar BoulevardArlington, TX 76011-4511NRC Senior Resident InspectorArkansas Nuclear OneP. O. Box 310London, AR 72847U. S. Nuclear Regulatory CommissionAttn: Mr. Kaly KalyanamMS O-8 B1One White Flint North11555 Rockville PikeRockville, MD 20852 ATTACHMENT TO2CAN111305Response to Request for Additional Information RegardingRequest for Alternative ANO2-ISI-004 Proposed Alternative to Extend the Third 10-YearInservice Inspection Interval for Reactor Vessel Weld Examinations Attachment to2CAN111305Page 1 of 2Response to Request for Additional Information RegardingRequest for Alternative ANO2-ISI-004 Proposed Alternative to Extend the Third 10-YearInservice Inspection Interval for Reactor Vessel Weld ExaminationsThe Nuclear Regulatory Commission (NRC) staff has reviewed the information providedby Entergy Operations, Inc. (Entergy, the licensee) for Arkansas Nuclear One, Unit 2(ANO-2) in its letter dated April 24, 2013 (Agencywide Documents Access andManagement System (ADAMS) Accession No. ML13115A015), and has determined thatadditional information is necessary to complete the review of Entergy's Request forAlternative ANO2-ISI-004.Based on the staff's review of Entergy's request, please provide responses that addressthe following requests:RAI 1:The reactor pressure vessel (RPV) weld that is the subject of Entergy's April 24, 2013request for alternative is identified as Weld No.02-001, which is the closure head-to-flange weld. Entergy identified that one-third of this weld was last examined in each ofthe Fall 1992, Spring 1994, and Spring 1997 outages, and that no unsatisfactoryindications were identified during those examinations. Please provide the followinginformation for Weld No. 02-001:a.Please describe the non-destructive techniques used to examine the weld duringall three examinations, including the applicable editions/addenda of the AmericanSociety of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code (Code),Section XI that were used.Weld Number 02-001 was examined in approximate one-third portions during thesecond 10-year inservice inspection (ISI) interval with magnetic particle and ultrasonicexamination methods. The second 10-year ISI interval began on March 26, 1990, andcompleted March 25, 2000. The examinations were performed using procedures to therequirements of ASME Section XI, 1986 edition, which was the code of record for thesecond 10-year ISI interval for these examinations.b.Identify whether there were any recordable indications during the threeexaminations. If so, please provide a summary of those indications and theirdisposition.There were no recordable service induced indications observed from any of the previousexams.Inside surface geometry from the flange side interface was observed and recorded withultrasonic examinations and accepted as a non-relevant condition. An internalsegregate was noted in one ultrasonic examination and was accepted.

Attachment to2CAN111305Page 2 of 2RAI 2:Reference 1 of Entergy's April 24, 2013 letter is Entergy's original request for NRCapproval of an alternative to the requirements of ASME Code,Section XI, Paragraph IWB-2412, Inspection Program B for ANO-2 (ADAMS Accession No. ML093030136). Item 3 ofthe attachment to that request identifies that the third 10-year inservice inspection (ISI)interval for ANO-2 was scheduled to end on March 25, 2011. Please identify whetherWeld No.02-001 was examined during the third interval. If so, provide the itemsrequested in RAI 1 for any examinations performed.Examinations were not performed during the third 10-year ISI interval on Weld Number 02-001as category B-A was not identified in the ISI program for examination.RAI 3:Please confirm that all of the provisions of Topical Report WCAP-16168-NP, Revision 1,"Risk-Informed Extension of the Reactor Vessel In-Service Inspection Interval" (ADAMSAccession No. ML060330504) are still met with the inclusion of Weld No.02-001 intoEntergy's 20-year alternative examination frequency.Note: For clarification, the request for the alternative and the associated safety evaluationrefers to Topical Report WCAP-16168-NP, Revision 2, "Risk-Informed Extension of the ReactorVessel In-Service Inspection Interval." This is the correct revision of the report.ASME Section XI, 1995 Edition with 1996 addenda, Table IWB-2500-1, Category B-A "PressureRetaining Welds in Reactor Vessel", includes Item B1.21 - Circumferential Head Welds,Item B1.22 - Meridional Head Welds, and Item B1.40 - Head to Flange Weld, and defines thecode required examinations, volumes, and frequency. Topical Report WCAP-16168-NP,Revision 2, specifically identifies ASME code category B-A (inclusive) for extension from 10 to20 years for examination frequency. The WCAP specifically lists item B1.40 as including weldsin Table 3-1 and further lists the closure head-to-flange weld in the discussion related to thelimiting conditions assessment in Section 3-1.All the provisions of Topical Report WCAP-16168-NP, Revision 2, are met with the inclusion ofWeld Number 02-001 into Entergy's 20-year alternative examination frequency.