ML17240A006

Request for Additional Information Regarding License Amendment Request for Measurement Uncertainty Recapture Power Uprate

ML17240A006
Person / Time
Site:	Peach Bottom
Issue date:	08/24/2017
From:	Richard Ennis Plant Licensing Branch 1
To:	Deborah Neff Exelon Generation Co
Ennis R, NRR/DORL/LPLI, 415-1420
References
CAC MF9289, CAC MF9290
Download: ML17240A006 (2)

Text

From: Ennis, Rick Sent: Thursday, August 24, 2017 6:34 PM To: David Neff Cc: David Helker; Richard.Gropp@exeloncorp.com

Subject:

PEACH BOTTOM ATOMIC POWER STATION, UNITS 2 AND 3 -

REQUEST FOR ADDITIONAL INFORMATION REGARDING LICENSE AMENDMENT REQUEST FOR MEASUREMENT UNCERTAINTY RECAPTURE POWER UPRATE (CAC NOS. MF9289 AND MF9290)

Attachments: final03 rai mf9289-90.doc By application dated February 17, 2017, as supplemented by letters dated March 20, 2017.

July 13, 2017, and August 8, 2017 (Agencywide Documents Access and Management System (ADAMS) Accession Nos. ML17048A444, ML17080A067, ML17195A285, and ML17220A214, respectively), Exelon Generation Company, LLC (Exelon, the licensee) submitted a license amendment request (LAR) for Peach Bottom Atomic Power Station (PBAPS), Units 2 and 3.

The amendments would revise the Renewed Facility Operating Licenses and Technical Specifications (TSs) to implement a measurement uncertainty recapture (MUR) power uprate.

Specifically, the amendments would authorize an increase in the maximum licensed thermal power level from 3,951 megawatts thermal (MWt) to 4,016 MWt which is an increase of approximately 1.66%.

The Nuclear Regulatory Commissions (NRC) staff is reviewing your submittal and has determined that additional information is needed to complete its review. The specific request for additional information (RAI) questions are attached. The RAI questions were provided in draft form to Mr. David Neff of the Exelon staff via e-mail on August 17, 2017. The draft questions were sent to ensure that the questions were understandable, the regulatory basis for the questions was clear, and to determine if the information was previously docketed. In a telephone call on August 24, 2017, Mr. Neff stated that Exelon would provide a response by September 5, 2017.

If you have any questions, please contact me at (301) 415-1420.

Richard B. Ennis, Senior Project Manager Plant Licensing Branch I Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-277 and 50-278

REQUEST FOR ADDITIONAL INFORMATION REGARDING PROPOSED LICENSE AMENDMENT MEASUREMENT UNCERTAINTY RECAPTURE POWER UPRATE EXELON GENERATION COMPANY, LLC PEACH BOTTOM ATOMIC POWER STATION - UNITS 2 AND 3 DOCKET NOS. 50-277 AND 50-278 By application dated February 17, 2017, as supplemented by letters dated March 20, 2017.

July 13, 2017, and August 8, 2017 (Agencywide Documents Access and Management System (ADAMS) Accession Nos. ML17048A444, ML17080A067, ML17195A285, and ML17220A214, respectively), Exelon Generation Company, LLC (Exelon, the licensee) submitted a license amendment request (LAR) for Peach Bottom Atomic Power Station (PBAPS), Units 2 and 3.

The amendments would revise the Renewed Facility Operating Licenses and Technical Specifications (TSs) to implement a measurement uncertainty recapture (MUR) power uprate.

Specifically, the amendments would authorize an increase in the maximum licensed thermal power level from 3,951 megawatts thermal (MWt) to 4,016 MWt which is an increase of approximately 1.66%.

The Nuclear Regulatory Commissions (NRC) staff is reviewing your submittal and has determined that additional information is needed to complete its review. The specific request for additional information (RAI) questions are shown below. The RAI questions were provided in draft form to Mr. David Neff of the Exelon staff via e-mail on August 17, 2017. The draft questions were sent to ensure that the questions were understandable, the regulatory basis for the questions was clear, and to determine if the information was previously docketed. In a telephone call on August 24, 2017, Mr. Neff stated that Exelon would provide a response by September 5, 2017.

Nuclear Performance and Code Review Branch (SNPB)

Reviewer: Kevin Heller SNPB-RAI-1 TSAR1, Section 3.2.1, Fracture Toughness, states, in part, that PBAPS was evaluated for a fluence that bounds the required value for operation at thermal power optimization (TPO) conditions. The first sentence on page 3-2 of the TSAR describes the method used to calculate the neutron fluence for TPO.

Confirm that the water density distribution throughout the core is either bounded or doesnt decrease significantly relative to the PBAPS current licensing basis conditions (i.e., CLTP/MELLLA+). If the water density distribution is not bounded:

1 Attachment 5 to the licensees application, GE - Hitachi Nuclear Energy (GEH), Safety Analysis Report for Peach Bottom Atomic Power Station, Units 2, and 3, Thermal Power Optimization, NEDC-33873P, Revision 0, dated February 2017, summarizes the evaluations performed for PBAPS for the proposed MUR. This proprietary report is referred to as the TSAR (i.e., Thermal Power Optimization Safety Analysis Report). A public version of the TSAR, GEH report NEDO-33873, is contained in Attachment 7 to Exelons application.

a) Provide water density distributions throughout the core for both CLTP/MELLLA+ and the proposed TPO/MELLLA+ conditions, and b) Explain why the method used to calculate the neutron fluence for TPO is acceptable given the water density changes.