ML14119A012

Draft Requests for Additional Information (Apla) Request RR-003

ML14119A012
Person / Time
Site:	Monticello
Issue date:	04/11/2014
From:	Beltz T A Plant Licensing Branch III
To:	Rippy L R Northern States Power Co
References
MF3050
Download: ML14119A012 (4)

Text

1 NRR-PMDAPEm Resource From: Beltz, Terry Sent: Friday, April 11, 2014 1:07 PM To: Rippy, L. Randal Cc: Kissinger, Peter W.; Eckholt, Gene F. (Eugene.Eck holt@xenuclear.com); Loeffler, Richard A.;

Carlson, Robert; Reisifard, Mehdi; Audrain, Margaret

Subject:

Monticello Nuclear Generating Plant - Draft R equests for Additional Information (APLA) re:

Request RR-003 (TAC No. MF3050)

Dear Mr. Rippy:

By letter to the U.S. Nuclear Regulatory Commission (NRC) dated October 31, 2013 (Agencywide Documents Access and Management System Accession No. ML13308A390), Northern States Power Company - a Minnesota corporation (NSPM), doing business as Xc el Energy, submitted Request RR-003. In RR-003, NSPM requests authorization to implement a risk-informed/safety-based inservice inspection (ISI) program based on American Society of Mechanical Engineers (ASME) Boiler and Pressure Code Case N-716, "Alternative Piping Classification and Examination Requirements,Section XI, Division 1," for ASME Class 1 and 2 piping welds for the fifth 10-year ISI interv al at the Monticello Nuclear Generating Plant.

The NRC staff in the Probabilistic Risk Assessment Licensing Branch of the Office of Nuclear Reactor Regulation has identified areas where additional information is needed to complete its review. Draft requests for additional information (RAI) are provided below.

You may accept these draft RAIs as formal Requests for Additional Information and provide a response by May 23, 2014. You may also request to discuss the contents of these draft RAIs with the NRC staff in a conference call.

Please let me know if you have any questions or concerns.

Sincerely, TERRY A. BELTZ, SENIOR PROJECT MANAGER U.S. Nuclear Regulatory Commission One White Flint North 11555 Rockville Pike Rockville, MD 20852-2738 Mail Stop: O-8D15

REQUEST FOR ADDITIONAL INFORMATION REGARDING REQUEST RR-003 IMPLEMENTATION OF A RISK-INFORMED/SAFETY-BASED INSERVICE INSPECTION PROGRAM BASED ON ASME BOILER AND PRESSURE CODE CASE N-716 FOR ASME CLASS 1 AND 2 PIPING WELDS FOR THE FIFTH TEN-YEAR INSERVICE INSPECTION INTERVAL MONTICELLO NUCLEAR GENERATING PLANT DOCKET NO. 50-263

2 (TAC NO. MF3050)

By letter to the U.S. Nuclear Regulatory Commission (NRC) dated October 31, 2013 (Agencywide Documents Access and Management System (A DAMS) Accession Number ML13308A390), Northern States Power Company - Minnesota corporation (NSPM), doing business as Xcel Energy, submitted Request RR-003 for NRC review and approval. RR-003 requests authorization to implement a risk-informed/safety-based (RIS_B) inservice inspection (ISI) program based on American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code Case N-716 for ASME Class 1 and 2 piping welds for the fifth 10-year ISI interval at the Monticello Nuclear Generating Plant, Unit 1.

The NRC staff in the Probabilistic Risk Assessment Licensing Branch (APLA) of the Office of Nuclear Reactor Regulation has reviewed the October 31, 2013, submittal, and identified that the following requests for additional information (RAI) are needed to complete its review:

RAI APLA-1 The Safety Evaluation Report (SER) related to EPRI Risk-Informed Inservice Inspection Evaluation Procedure (EPRI TR-112657, Rev. B) states that EPRI TR-112657, Rev. B, does not include a detailed discussion of the specific assumptions to be used to guide the assessment of the direct and indirect effects of segment failures.

The SER states that specific assumptions regarding the direct and indirect effects of pipe segment failure should be developed by the individual licensees and should form part of the onsite documentation.

NSPM states in the license amendment request (LAR) submittal dated October 31, 2013, that under the solution for F&O [Facts & Observations] originating from Supporting Requirement IFSN-A6 that a qualitative assessment was performed for the following flood failure mechanisms: submergence; spray; jet impingement; pipe whip; humidity; condensation and temperature.

a) Please clarify if specific guidelines and assumptions used for determining direct and indirect effects of flooding, including assumptions on the failure of components affected by the pipe break, have been developed for this application.

b) Please clarify if the loss of mitigating ability (as discussed in Section 3.2.4 of the SER), where segment failures occur that only cause failure of mitigating functions but do not cause a plant trip, has been considered in consequence evaluations for this application in accordance with EPRI TR-112657.

RAI APLA-2 According to Regulatory Issue Summary 2007-06, "Regulatory Guide 1.200 Implementation," the NRC staff expects licensees to fully address all scope elements wi th Revision 2 of Regulatory Guide (RG) 1.200 by the end of its implementation period (i.e., one year after the issuance of Revision 2 of RG 1.200). Revision 2 of RG 1.200 endorses, with exceptions and clarifications, the combined American Society of Mechanical Engineers (ASME)/American Nuclear Society (ANS) probabilistic risk assessment (PRA) standard (ASME/ANS RA-Sa-2009).

Given that the implementation date of Revision 2 to RG 1.200 was in April 2010, and your LAR was submitted in October 2013, please describe any gaps between the 2013 focused scope peer review of the PRA model used in this application and RG 1.200, Revision 2, that are relevant to this submittal and the impact on the application.

3 Hearing Identifier: NRR_PMDA Email Number: 1254 Mail Envelope Properties (Terry.Beltz@nrc.gov20140411130600)

Subject:

Monticello Nuclear Generating Plant - Draft Requests for Additional Information (APLA) re: Request RR-003 (TAC No. MF3050) Sent Date: 4/11/2014 1:06:53 PM Received Date: 4/11/2014 1:06:00 PM From: Beltz, Terry Created By: Terry.Beltz@nrc.gov Recipients: "Kissinger, Peter W." <Peter.Kissinger@xenuclear.com> Tracking Status: None "Eckholt, Gene F. (Eugene.Eckholt@xenuclear.com)" <Eugene.Eckholt@xenuclear.com> Tracking Status: None "Loeffler, Richard A." <Richard.Loeffler@xenuclear.com>

Tracking Status: None "Carlson, Robert" <Robert.Carlson@nrc.gov> Tracking Status: None "Reisifard, Mehdi" <Mehdi.Reisifard@nrc.gov> Tracking Status: None "Audrain, Margaret" <Margaret.Audrain@nrc.gov>

Tracking Status: None "Rippy, L. Randal" <Randal.Rippy@xenuclear.com> Tracking Status: None

Post Office: Files Size Date & Time MESSAGE 5307 4/11/2014 1:06:00 PM

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