ML112160007

Email, Request for Additional Information, Nrr/Dci/Emcb Review, Round 3, Amendment Request for Extended Power Uprate to Increase the Maximum Reactor Core Power Operating Limit from 3898 to 4408 Mwt

ML112160007
Person / Time
Site:	Grand Gulf
Issue date:	08/03/2011
From:	Wang A Plant Licensing Branch IV
To:	Burford J, Millar D Entergy Operations
Wang A, NRR/DORL/LPL4, 301-415-1445
References
TAC ME4679
Download: ML112160007 (2)

Text

From:

Wang, Alan Sent:

Wednesday, August 03, 2011 8:05 PM To:

'MILLAR, DANA'; 'Jerry Burford' Cc:

Lent, Susan; Burkhardt, Janet

Subject:

Grand Gulf Extended Power Uprate Mechanical and Civil Engineering Branch Third Round Request for Information (ME4679)

Dana and Jerry, By letter dated September 8, 2010 (Agencywide Documents Access and Management System, Accession No. ML1002660403), Entergy Operations, Inc. (Entergy, the licensee), submitted a request to amend the Facility Operating License No. NPF-29 for Grand Gulf Nuclear Station, Unit 1 (GGNS). The licensee proposed a license amendment request (LAR) for an extended power uprate (EPU) to increase the maximum reactor core power operating limit from 3898 megawatts thermal (MWt) to 4408 MWt. The U.S. Nuclear Regulatory Commission (NRC) staff has determined that the following additional information is needed for the NRC staff to complete our review of this amendment. This request for additional information (RAI) was discussed with Mr. Jerry Burford of your staff on July 28, 2011, and it was agreed that a response would be provided within 30 days of receipt of this E-mail. 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 are third round RAIs related to your June 15, 2011, response to the Mechanical and Civil Engineering Branch review:

RAI 1

In its June 15, 2011, response to RAI 2 (b), Entergy stated that the 13.1 percent feedwater (FW) flow rate increase accompanying the proposed EPU implementation at the GGNS does not affect the stresses in the FW piping system. The licensee stated that the design basis of the FW piping system does not include loads which are governed by flow rate, including water hammer and transient loads. As such, the FW pipe stress analysis of record (AOR) does not credit pipe stresses resulting from flow-induced transients. While the design basis of the FW piping system does not include stresses resulting from water hammer and other flow-induced transients, the NRC staff requests that the licensee provide a technical justification which demonstrates that the FW piping and supports will maintain their structural integrity following transients whose load consequences would be amplified by the proposed flow increase accompanying EPU implementation at GGNS. Transients which should be considered include, but are not limited to, a FW pump trip, FW regulating valve closure and FW isolation valve closure. This technical justification should quantitatively demonstrate that the American Society of Mechanical Engineers Boiler and Pressure Vessel (ASME B&PV) Code allowable values used in the original design of the FW piping system will continue to be satisfied following these events, upon implementation of the proposed EPU at GGNS.

RAI 2

Note 11 of Table 2.2-7 of the Power Uprate Safety Analysis Report (PUSAR), submitted as part of the GGNS EPU license amendment request (LAR) on September 8, 2010, indicates that the low alloy steel forging portion of the FW nozzle at GGNS can be qualified for acceptable fatigue behavior using the methods of NUREG-0619, BWR Feedwater Nozzle and Control Rod Drive

Return Line Nozzle Cracking, or Revision 1 of GE-NE-523-A71-0594-A, Alternate BWR Feedwater Nozzle Inspection Requirements. Please state the specific inspection provisions of either reference which will be used to qualify the component for fatigue usage following EPU implementation. Additionally, please provide additional information regarding the proposed implementation schedule for these inspection provisions.

Alan Wang, Project Manager Plant Licensing Branch IV Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation