ML082910073

TAC MD8717, Draft Rais, Relief Requests Plant ISI Program Third 10-year Closeout

ML082910073
Person / Time
Site:	FitzPatrick
Issue date:	10/16/2008
From:	Bhalchandra Vaidya Plant Licensing Branch 1
To:	Eugene Dorman FitzPatrick
vaidya B K, NRR/Dorl/lpl1-1, 415-3308
References
TAC MD8717
Download: ML082910073 (5)

Text

From: Bhalchandra Vaidya Sent: Thursday, October 16, 2008 4:34 PM To: 'Dorman, Eugene' Cc: Mark Kowal

Subject:

Fitz Patrick, MD8717, Draft RAIs Draft RAIs for the Relief Request Re: Plant ISI program Third Ten Year Close Out are provided below.

Please Review the RAIs and let me know, whether the licensee understands the RAIs clearly and when the supplemental submission responding to the RAIs can be expected. And if a Tele-conference is needed, let me know your convenient Dates and Time in the Next week. ================================== REQUEST FOR ADDITIONAL INFORMATION 1 Request for Relief RR-CRV-1 (Part A), ASME Code,Section XI, Examination Category B-A, Items B 1.21 and B1.22, Reactor Pressure Vessel (RPV) Bottom Head Welds The licensee has requested relief from examining 100% of the ASME Code-required volumes for Welds VC-BH-2-3 & VV-BH-2A thru 2F. The licensee has indicated that no coverage or examination of these welds is possible for the following reasons.

Access to the area is limited to four 18" diameter manways 90° apart in the vessel support skirt. In addition, the one hundred and thirty-seven (137) control rod drives and forty-three (43) in-core monitor instrumentation penetrations present extensive interference.

The positioning and spacing of these components prevent an inspector from physically being able to reach them and limits the surface distance required to perform the examination (reference attached photograph depicting configuration). This combined with the curvature of the bottom head and the Bioshield wall narrowing in this area precludes access. Permanent vessel insulation and limited storage space for those insulation panels which require removal is extremely limited based on the size of the manways.

The ASME Code requires that essentially 100% of the accessible length of the subject welds be examined. However, the licensee has stated that there has been no volumetric examination of the accessible portions of the subject welds. In the relief request, the licensee does not adequately demonstrate impracticality of examination for these welds. The relief request contains copies of photographs of the area below the RPV; however, the copies contained in the electronic file are of poor quality and cannot be used to determine accessibility to the subject welds. Please provide a detailed description to clarify the interferences caused by the control rod drive housings and in-core instrument nozzles. Also include readable photographs or sketches in order to clarify the basis to demonstrate the reason why it is impractical to access the subject welds from the outside surface of the RPV. In addition please confirm that circumferential weld VC-BH-1-2 was volumetrically examined and that the examinations met ASME Code requirements.

The staff has noted that other licensees with similar vintage plants have been able to inspect the accessible portion of the subject welds either from the outside surface of the RPV, or through the use of remote inspection devices applied from the inside surface of the RPV. Discuss whether new technologies have been considered, e.g., robotic tools, applied from the inside of the RPV, which would allow examinations of the subject welds to occur.

2 Request for Relief RR-CRV-1 (Part B), ASME Code,Section XI, Examination Category B-D, Item B3.90, Full Penetration Welded Nozzles in Vessels The licensee has included multiple RPV nozzle-to-shell and nozzle-to-head welds in the subject relief request. Several axial and circumferential coverage calculations and related sketches depicting angle beam orientations for coverage areas are included in the licensee's submittal. However, in many of the licensee's sketches, it is unclear which portion and how much of the ASME Code-required volumes have been completed. Please re-submit cross-sectional drawings showing volume coverage for each of the ultrasonic angles applied. Include written descriptions of the ASME Code-required volumes and areas of completed coverage for each of the techniques (near surface, inner 15%, and full volume) used on these welds. Summarize scanning directions and techniques, list the materials for the base materials and welds, and state whether any reportable indications were detected during the examinations.

The licensee has provided some limited drawings depicting interferences from insulation brackets and rings, and proximity of mirror insulation that cause scanning difficulties. However, no discussion of why this insulation cannot be removed is given. Please discuss whether the limited examinations caused by interference from insulation cannot be remedied by removal of the subject insulation and supporting appurtenances.

Clarify whether the methods used to examine each of the RPV nozzle-to-shell or head welds have been qualified in accordance with performance demonstration requirements per ASME Code,Section XI, Appendix VIII.

3 Request for Relief RR-CRV-1 (Part C), ASME Code,Section XI, Examination Category B-G-1, Item B6.40, Reactor Vessel Flange Ligament The licensee has included, as Enclosure 10

[1], a rough hand sketch depicting areas of limited scanning. However, insufficient text is provided in order to make use of the drawing. In order to demonstrate impracticality, submit a detailed written description of how the machined areas on either side of the threaded areas in the RPV flange impacted ultrasonic scanning. In addition, describe the ultrasonic methods employed to maximize coverage for the subject areas.

4 Request for Relief RR-CRV-1 (Part D), ASME Code,Section XI, Examination Category B-K, Item B10.10, Integrally Welded Attachments The licensee provided, as Enclosure 11 1, two drawings showing the RPV stabilizer brackets and listing surface and visual coverage. However, insufficient text has been provided to discuss the exact cause of the limited surface examination. Submit further description of the limiting conditions for performing the magnetic particle examinations on the integral attachment welds. In addition, state whether surface examination coverage could be increased by using liquid penetrant examination techniques. Also, state whether the surface and VT-1 examinations detected any reportable conditions.

5 Request for Relief RR-CRV-1 (Part E) ASME Code,Section XI, Examination Category C-A, Item C1.20, Pressure Retaining Welds in Pressure Vessels The licensee provided, as Enclosure 12 1, two drawings showing ultrasonic angle beams applied and scanning obstructions due to supports and weld-o-lets. However, insufficient text is given to adequately describe the level of ASME Code coverage was obtained. Submit further description of the limiting conditions for performing ultrasonic examination, and re-submit the cross-sectional sketch showing areas of completed coverage for each of the ultrasonic techniques employed.

6 Request for Relief RR-CRV-1 (Part F) ASME Code,Section XI, Examination Category C-B, Item C2.22, Pressure Retaining Nozzle Welds in Vessels The licensee provided, as Enclosure 13 1, two drawings showing ultrasonic angle beams applied and geometrical conditions that may affect ultrasonic scanning. However, insufficient text is given to adequately describe the level of ASME Code coverage was obtained. Submit further description of the limiting conditions for performing ultrasonic examination, and re-submit the cross-sectional sketch showing areas of completed coverage for each of the ultrasonic techniques employed.

7 Request for Relief RR-CRV-1 (Part G) ASME Code,Section XI, Examination Category R-A, Item R1.20 (Category C-F-2, Item C 5.51)

Pressure Retaining Welds in Carbon or Low Alloy Steel Piping

1. Enclosures 10, 11, 12, 13, and 14 are not included in the RAI and can be found in the licensee's submittal dated April 30, 2008 The licensee has provided a drawing, Enclosure 14 1, which is believed to show the coverage obtained from the pipe side of the weld for axial scans. However, insufficient text is included to describe the conditions that limit ultrasonic scanning in both the axial and circumferential directions. Please submit further written description to demonstrate impracticality. In addition, describe the ultrasonic techniques employed.

In addition to the bases for impracticality, state whether any outside diameter surface feature, such as weld crown, diametrical weld shrinkage, or surface roughness conditions caused limited volumetric coverage during the subject piping weld examinations. Discuss the efforts that were used to correct these conditions.

Clarify whether the methods used to examine the subject piping weld have been qualified in accordance with performance demonstration requirements per ASME Section XI, Appendix VIII.

============================== Bhalchandra K. Vaidya Licensing Project Manager U. S. NRC, NRR/DORL 301-415-3308 (Office) 301-415-1222 (Fax)

Bhalchandra.Vaidya@nrc.gov E-mail Properties Mail Envelope Properties (1D658D167B82F54585A33C1A31821B681ECE934BEB)

Subject:

Fitz Patrick, MD8717, Draft RAIs

Sent Date: 10/16/2008 4:34:03 PM Received Date: 10/16/2008 4:34:00 PM From: Bhalchandra Vaidya

Created By: Bhalchandra.Vaidya@nrc.gov

Recipients:

EDorman@entergy.com ('Dorman, Eugene')

Tracking Status: None Mark.Kowal@nrc.gov (Mark Kowal)

Tracking Status: None

Post Office:

HQCLSTR02.nrc.gov

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MESSAGE 18106 10/16/2008 Options Expiration Date:

Priority: olImportanceNormal ReplyRequested: False Return Notification: False

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