Margin Management Configuration Management Benchmarking Group June 21, 2011 Michael Hayes Configuration Control SME

Overview of Margin Management Design and operating margins are understood, considered in decision-making, and managed consistent with design and licensing requirements. Effects of changes on design and operating margins are identified, evaluated, and documented before the changes are approved for implementation. Degraded conditions that reduce design or operating margins for systems important to safety and reliability are identified, evaluated, understood, and mitigated. 1/18/2019

Benefits of Margin Management Operational configuration is conservatively maintained within the design requirements, and design requirements are conservatively maintained within the design bases. Operators and plant systems have sufficient flexibility to accommodate routine activities and the capability to respond to anticipated transients and accident scenarios effectively. Low margin concerns are identified, evaluated, prioritized, tracked, and resolved. System Managers evaluate aggregate impact of low margin concerns associated with their system. 1/18/2019

Margin Model

Margins are Understood and Considered Issues are identified in terms of margin within: Corrective Action Program System & Component monitoring programs Operability Evaluations & Determinations Operational Decision Making process Site or Corporate Business Plan Issues brought before the Plant Health Committee (PHC) – Subcommittee are evaluated in terms of margin. Action is taken on High Risk systems that have the low Margin.

Changes are identified, evaluated, & documented The effects of changes on design and operating margins are identified, evaluated, and documented before the changes are approved. Design Input and Impact Screening documentation includes analysis of the impact of the change on margins. Processing of Procedures includes documentation of the impact of the change on margins. The applicable interfacing departments provide concurrence that reductions in margins have been identified and sufficiently justified.

Address Degraded Conditions that Reduce Margin Engineering programs, testing, and predictive and preventive maintenance activities confirm that systems continue to provide assumed design margins. The Corrective Action Program (CAP) Process and the Operability Determination Process are utilized to assure that degraded conditions are evaluated and addressed. Aggregate impact of margin degradation is identified, evaluated, understood, and a need for mitigation strategies, if any, assessed.

Margins Maintained in Process Processing of Procedures Project Review Committee Configuration Change Control for Permanent Physical Plant Changes Document Change Requests Temporary Configuration Changes Control of Design Analyses Engineering Technical Evaluations Implementing and Managing Engineering Programs Plant Health Committee System Health Monitoring System Performance Monitoring and Analysis System Vulnerability Review Process Operability Determinations Corrective Action Program (CAP) Performance Centered Maintenance (PCM) Process Predictive Maintenance Program Operator Work-Around Program Operational and Technical Decision Making Process

Margin Issue Database As an extra barrier in addition to these processes, Exelon has developed a margin issue database and associated lifecycle description. An entry into the margin issue database may be made at the discretion of the individual with a concern. The margin issue database is used to obtain PHC Subcommittee review of a concern that existing margin may not be sufficient to protect a design or operating limit. (Not when the limit has already been exceeded as in a nonconforming condition or Operability Determination.)

Margin Issue Lifecycle Issue Identified Issue owner enters issue into database Margin Management Coordinator prepares report for PHC Subcommittee review Margin Management Coordinator informs Issue Owner that clarification is required PHC Subcommittee reviews issues in report Issue sufficiently defined? PHC Subcommittee comments as to required clarifications No Yes Margin acceptable as is? PHC Subcommittee provides basis for decision and closes issue Yes No PHC Subcommittee prioritizes and provides action plan and action tracking number Issue can be addressed thru LOE activity? Yes No PHC Subcommittee prioritizes and provides action plan and Portfolio Director number and IR number (if applicable) PHC prioritizes and allocates resources to address the margin issue Actions required to address margin issue are performed

SRM – Margin Management – Part 1

SRM – Margin Management – Part 2

SRM – Margin Management – Part 3

System IQ - Margin

System IQ – Indicator Details

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