ML121290617

E-mail, Request for Additional Information, Relief Request ISI-17, Use of ASME Code Cases N-638-4 and N-504-4 for Alternative Repair of RHR LPCI Weld During Refueling Outage RF-18, Third 10-Year Inservice Inspection Interval

ML121290617
Person / Time
Site:	Grand Gulf
Issue date:	05/08/2012
From:	Wang A Plant Licensing Branch IV
To:	Rolonda Jackson, Perino C, Seiter J Entergy Operations
Wang, A B, NRR/DORL/LPLIV, 415-1445
References
TAC ME8525
Download: ML121290617 (2)

Text

From: Wang, Alan Sent: Tuesday, May 08, 2012 2:28 PM To: Perino, Christina; SEITER, JEFFERY ALAN; JACKSON, RITA R Cc: Lent, Susan; Burkhardt, Janet

Subject:

Grand Gulf Nuclear Station Request for Additional Information (RAI)

Regarding Relief Request ISI-17 (ME8525)

Rita, Jeff and Christina, By letter dated May 2, 2012 (Agency-wide Documents Access and Management System (ADAMS) Accession No. ML12124A245), Entergy Operations Incorporated (Entergy, the licensee) requested U.S. Nuclear Regulatory Commission for review and approval of Relief Request (RR) ISI-17 to repair degraded weld N06B-KB at the "C" nozzle in the Residual Heat Removal (RHR) / Low Pressure Core Injection (LPCI) system. The licensee proposes to install a structural weld overlay on the affected weld. The proposed RR is to perform an alternative repair of RHR / LPCI "Cn Nozzle to Safe End Weld N06B-KB using the provisions of American Society of Mechanical Engineers (ASME) Code Cases N-638-4 and N-504-4.

The NRC staff has determined that the following additional information is needed to complete our review of this request. This request for additional information (RAI) was discussed with Mr.

Jeffrey Seiter, on May 8, 2012, and it was agreed that a response would be provided by May 10, 2012. If circumstances result in the need to revise the requested response date, please contact me at (301) 415-1445 or via e-mail at Alan.Wang@nrc.gov.

The following RAIs are related to your request in letter dated May 2, 2012:

1. On page 5 of the RR, the licensee stated that it will perform fracture mechanics analyses to predict crack growth of the detected flaw based on intergranular stress corrosion cracking (IGSCC) and fatigue. Please provide a discussion on the following items:

(a) Discuss the crack growth rate of the IGSCC that will be used for the crack growth calculation and provide the reference, (b) Discuss briefly the fracture mechanics analyses (i.e., methodology, technical basis, input, initial flaw size), and (c) Discuss the acceptance criteria for the results of the fracture mechanics analyses.

2. On Page 7 of the RR, item (d) states that PT [penetrant test] examination will be performed in accordance with the ASME Code,Section III. Confirm that the acceptance criteria for the PT results (indications detected) will be based on the ASME Code,Section III, NB-5000.

3. Provide the nominal diameter of the pipe and pipe wall thickness. Figure 2 of the relief request shows some dimensions of the overlay and nozzle configuration. Provide a more detailed design drawing of the weld overlay, nozzle, safe end and pipe.

4. Discuss any surface preparation for the nozzle, safe end, and pipe prior to weld overlay installation. If the surface configuration of the weld/nozzle is changed by the surface preparation process, discuss whether the weld be reexamined following the surface preparation.

Alan Wang Project Manager (Grand Gulf Nuclear Station)

Nuclear Regulatory Commission Division of Operating Reactor Licensing Alan.Wang@NRC.gov Tel: (301) 415-1445 Fax: (301) 415-1222