ML14114A740

Application of GE Hitachi Simplified Stability Solution GS3 Pre-Submittal Presentation

ML14114A740
Person / Time
Site:	Clinton
Issue date:	04/09/2014
From:	Exelon Generation Co
To:	Division of Operating Reactor Licensing
Blake Purnell, NRR/DORL 415-1380
References
Download: ML14114A740 (10)

Text

Clinton Power Station Application of GE Hitachi Simplified Stability Solution (GS3)

Pre-Submittal Meeting pril 9, 2014

Meeting Agenda Objectives Key Project Personnel Key Aspects of GS3 Application of GS3 to CPS GS3 Benefits for CPS GS3 Motivation and Basis SAR Content and Sample Demonstration Results Conclusion Project Schedule

Objectives The purpose of this meeting is to discuss the Clinton Power Station (CPS) license amendment request (LAR) for application of the GE Hitachi Simplified Stability Solution (GS3) methodology

- Address key aspects of the GS3 methodology

- Address technical topics associated with the proposed LAR

- Discuss licensing activities and schedule

• Obtain NRC input on the proposed application of this methodology at CPS

ey Project Personnel Exelon Technical Lead: Andy Olson Exelon Licensing Lead: Tim Byam Exelon Core Design: Dale Bradish GEH Technical Lead: Juswald Vedovi GEH Licensing Lead: Jim Harrison GEH Project Manager: Charles Lamb

ey Aspects of GS3 GS3 is a TRACG methodology alternative to the DIVOM methodology used for the calculation of the stability based OLMCPRs in the stability long-term solution (LTS) Option III implemented at CPS GS3 is a methodology improvement rather than a new LTS and it is built on a Best Estimate Plus Uncertainty (BEPU) methodology GS3 does not include any change to the backup stability protection aspect of the current Option III solution implemented at CPS GS3 uses TRACG to calculate the MCPR at the time of oscillation suppression to show that the SLMCPR is protected GS3 does not calculate the Decay Ratio nor use frequency domain analysis

pplication of GS3 to CPS GS3 implementation at CPS does not require any hardware or software changes in the plant GS3 application to CPS uses the existing detection algorithm, the Period Based Detection Algorithm (PBDA)

The best-estimate TRACG code is used to determine the MCPR margin during reasonably limiting instability event simulations for GS3 applications to CPS The GS3 methodology generic Licensing Topical Report (LTR),

NEDE-33766, Rev. 0, was submitted for NRC review in September 2013 The proposed CPS LAR is based on a plant-specific GS3 SAR for CPS and does not require NRC approval of the generic LTR The GS3 methodology used in the plant-specific SAR for CPS is identical to the methodology documented in the generic GS3 LTR NEDE-33766, Rev. 0

GS3 Benefits for CPS Improve plant safety through better understanding of simulated phenomena More realistic analyses Comply with applicable GDC (i.e., GDC 10 and 12)

• Eliminate/reduce impact on plant operation Reduce chances of spurious scram or alarms - CPS currently operating with minimum recommended OPRM setpoints Optimize core reload design and improve thermal limit margins - excess conservatism in current stability methodology results in stability analyses establishing the MCPR operating limit

• Use of the integrated TRACG approach will vastly simplify the MCPR protection basis versus the current multi-step DIVOM based process

• Cycle-specific confirmation check will be used to select the OPRM setpoint

GE Hitachi Presentation roject Schedule Submittal of the CPS GS3 LAR is currently scheduled for mid-June 2014 Exelon will request approval of the amendment by April 30, 2015 Expedited NRC review is required to support the CPS refueling outage in May 2015 The core design will be completed using the GS3 methodology

• Exelon will implement the approved amendment prior to startup from refueling outage C1R15 (startup is currently scheduled for May 13, 2015)

• Implementation will include updating the following documents:

CPS Technical Specification (TS) 5.6.5, Core Operating Limits Report, to reflect the new approved methodology Cycle 16 Core Operating Limits Report (COLR) to reflect OPRM setpoint and OLMCPRs TS Bases, as required

Questions