ML12132A436
| ML12132A436 | |
| Person / Time | |
|---|---|
| Site: | Monticello  |
| Issue date: | 05/11/2012 |
| From: | Tam P Plant Licensing Branch III |
| To: | Rippy L, Loeffler R Northern States Power Co |
| Tam P | |
| References | |
| TAC ME8068 | |
| Download: ML12132A436 (1) | |
Text
Accession No. ML12132A436 From: Tam, Peter Sent: Friday, May 11, 2012 4:38 PM To: 'Loeffler, Richard A.'; Rippy, L. Randal Cc: Wallace, Jay; Tsao, John
Subject:
Monticello draft RAi - Relief Request RR-004 (TAC ME8068)
Randy:
By letter dated February 28, 2012, Northern States Power Company - Minnesota (the licensee) submitted request for alternative RR-004, Alternative Requirements for Wall Thickness Restoration of Class 2 and 3 Carbon Steel Piping for Raw Water Service,Section XI, Division 1 (Accession No. ML12059A403). The licensee proposes to use the provisions of American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code (Code) Case N-661-2 for repair of Class 2 and 3 carbon steel piping for raw water service at Monticello Nuclear Generating Plant. This Code Case has not been approved for use in Regulatory Guide 1.147, Revision 16. In order to complete our review, the NRC staff needs additional information as follows:
- 1. Please specify the expected start and end dates of the Monticello Nuclear Generating Plant Fifth Inservice Inspection Interval.
- 2. The NRC staff is concerned about the exemption from volumetric examination for Class 3 weld overlays in Code Case N-661-2, paragraph (6)(c)(1), when the Construction Code does not require that full-penetration butt welds in the same location be volumetrically examined. This exemption is not found in Code Case N-661-1. Please specify whether this exemption from volumetric examination is to be employed. If the exemption is to be employed:
- a. Please state which Construction Code was used for the service water piping and whether the Construction Code would require volumetric examination of a butt weld at the weld overlay site.
- b. Provide detailed technical justification for assurance of the structural integrity of the weld overlay if it is not volumetrically examined.
You may accept this draft RAI as formal Request for Additional Information and formally respond to the above questions by June 15, 2012. Alternatively, you may request to discuss with the NRC staff, in a conference call, the contents of this draft RAI and/or proposed response date.
Peter S. Tam Senior Project Manager (for D. C. Cook and Monticello)
Plant Licensing Branch III-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Tel. 301-415-1451