ML12198A317

Draft RAI for Relief Request RR-004

ML12198A317
Person / Time
Site:	Monticello
Issue date:	07/16/2012
From:	Tam P Plant Licensing Branch III
To:	Rippy L, Kissinger P, Loeffler R Northern States Power Co
Tam P
References
TAC ME8068
Download: ML12198A317 (1)

Text

Accession No. ML12198A317 From: Tam, Peter Sent: Monday, July 16, 2012 1:13 PM To: Kissinger, Peter W.; 'Loeffler, Richard A.'; Rippy, L. Randal Cc: Wallace, Jay; Tsao, John; Lupold, Timothy; Frankl, Istvan

Subject:

Monticello - Draft RAI on ISI Relief Request RR-004 re. Code Case N-661-2 (TAC ME8068)

Rick, Randy:

By letter dated February 28, 2012, Northern States Power Company - Minnesota submitted a request for alternative, Relief Request 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 branch requests 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 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 choose to accept this e-mail as conveying a formal RAI and formally respond by 8/31/2012, or request to discuss with the NRC staff in a conference call the contents above and a different 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