2CAN111305, Unit 2, Response to Request for Additional Information Related to Relief Request ANO2-ISI-004

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:	Pyle S Entergy Operations
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
2CAN111305, ANO2-ISI-004, TAC MC9768, TAC MF2319
Download: ML13316C078 (5)

Text

Entergy Operations, Inc.

1448 S.R. 333 Russellville, AR 72802 Tel 479-858-4704 Stephenie L. Pyle Manager, Licensing Arkansas Nuclear One 2CAN111305 November 11, 2013 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555

Subject:

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

References:

1. Entergy letter dated April 24, 2013, Additional Reactor Vessel Closure Head Weld Request for Alternative ANO2-ISI-004, Proposed Alternative to Extend the Third 10-Year Inservice Inspection Interval for Reactor Vessel Weld Examinations (2CAN041303) (ML13115A015)

2. Letter from NRC to Mr. Gordon Bischoff, Manager, Owners Group Program Management Office, Final Safety Evaluation of Pressurized Water Reactor Owners Group (PWROG) Topical Report (TR) WCAP-16168-NP, Revision 2, Risk-Informed Extension 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 NRCs approval of an alternative to the requirements 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 essentially 100% of the reactor vessel pressure retaining Examination Category B-A and B-D welds be performed once each ten-year inservice inspection (ISI) interval. The alternative was to extend the examination frequency to once every 20 years. The request was based upon the methodology outlined in Reference 2.

On reviewing the submittal, the NRC staff requested additional information (RAI) to continue the review and issued Reference 3. Attached is Entergys response to the request.

2CAN111305 Page 2 of 2 This submittal contains no regulatory commitments.

Should you have any questions, please contact me.

Sincerely, Original signed by Stephenie L. Pyle SLP/rwc

Attachment:

Response to Request for Additional Information Regarding Request for Alternative ANO2-ISI-004 Proposed Alternative to Extend the Third 10-Year Inservice Inspection Interval for Reactor Vessel Weld Examinations cc: Mr. Marc L. Dapas Regional Administrator U. S. Nuclear Regulatory Commission Region IV 1600 East Lamar Boulevard Arlington, TX 76011-4511 NRC Senior Resident Inspector Arkansas Nuclear One P. O. Box 310 London, AR 72847 U. S. Nuclear Regulatory Commission Attn: Mr. Kaly Kalyanam MS O-8 B1 One White Flint North 11555 Rockville Pike Rockville, MD 20852

ATTACHMENT TO 2CAN111305 Response to Request for Additional Information Regarding Request for Alternative ANO2-ISI-004 Proposed Alternative to Extend the Third 10-Year Inservice Inspection Interval for Reactor Vessel Weld Examinations

Attachment to 2CAN111305 Page 1 of 2 Response to Request for Additional Information Regarding Request for Alternative ANO2-ISI-004 Proposed Alternative to Extend the Third 10-Year Inservice Inspection Interval for Reactor Vessel Weld Examinations The Nuclear Regulatory Commission (NRC) staff has reviewed the information provided by Entergy Operations, Inc. (Entergy, the licensee) for Arkansas Nuclear One, Unit 2 (ANO-2) in its letter dated April 24, 2013 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML13115A015), and has determined that additional information is necessary to complete the review of Entergys Request for Alternative ANO2-ISI-004.

Based on the staffs review of Entergys request, please provide responses that address the following requests:

RAI 1

The reactor pressure vessel (RPV) weld that is the subject of Entergys April 24, 2013 request 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 of the Fall 1992, Spring 1994, and Spring 1997 outages, and that no unsatisfactory indications were identified during those examinations. Please provide the following information for Weld No. 02-001:

a. Please describe the non-destructive techniques used to examine the weld during all three examinations, including the applicable editions/addenda of the American Society 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 the second 10-year inservice inspection (ISI) interval with magnetic particle and ultrasonic examination methods. The second 10-year ISI interval began on March 26, 1990, and completed March 25, 2000. The examinations were performed using procedures to the requirements of ASME Section XI, 1986 edition, which was the code of record for the second 10-year ISI interval for these examinations.

b. Identify whether there were any recordable indications during the three examinations. If so, please provide a summary of those indications and their disposition.

There were no recordable service induced indications observed from any of the previous exams.

Inside surface geometry from the flange side interface was observed and recorded with ultrasonic examinations and accepted as a non-relevant condition. An internal segregate was noted in one ultrasonic examination and was accepted.

Attachment to 2CAN111305 Page 2 of 2

RAI 2

Reference 1 of Entergys April 24, 2013 letter is Entergys original request for NRC approval 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 of the 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 whether Weld No.02-001 was examined during the third interval. If so, provide the items requested in RAI 1 for any examinations performed.

Examinations were not performed during the third 10-year ISI interval on Weld Number 02-001 as 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 (ADAMS Accession No. ML060330504) are still met with the inclusion of Weld No.02-001 into Entergys 20-year alternative examination frequency.

Note: For clarification, the request for the alternative and the associated safety evaluation refers to Topical Report WCAP-16168-NP, Revision 2, Risk-Informed Extension of the Reactor Vessel 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 Pressure Retaining 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 the code required examinations, volumes, and frequency. Topical Report WCAP-16168-NP, Revision 2, specifically identifies ASME code category B-A (inclusive) for extension from 10 to 20 years for examination frequency. The WCAP specifically lists item B1.40 as including welds in Table 3-1 and further lists the closure head-to-flange weld in the discussion related to the limiting conditions assessment in Section 3-1.

All the provisions of Topical Report WCAP-16168-NP, Revision 2, are met with the inclusion of Weld Number 02-001 into Entergys 20-year alternative examination frequency.