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PWR Sump Performance (GSI-191) Industry Workshop. Hyatt Regency, Baltimore, Maryland October 18-19, 2012 Mark Richter Senior Project Manager Nuclear Energy Institute. GSI-191 Industry Workshop. Workshop Objectives
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PWR Sump Performance (GSI-191) Industry Workshop Hyatt Regency, Baltimore, Maryland October 18-19, 2012 Mark Richter Senior Project Manager Nuclear Energy Institute
GSI-191 Industry Workshop • Workshop Objectives • Provide guidance and information to PWR licensees to assist in the resolution and closure of this long-standing issue. • Provide the range of closure path options and applicability relative to SECY 12-0093. • Provide an opportunity for open discussion with peers and NRC staff to resolve questions and identify remaining issues.
GSI-191 Industry Workshop • Workshop Focus • Industry and Regulatory Perspectives • PWROG Closure Plan, STP Risk-Informed Project, and other coupled deterministic and risk-informed closure options • Bypass Testing, Defense-in Depth and Mitigation Strategies, and Operability Determination • Closure Option Templates based on options in SECY 12-0093 for Year-End Submittals
GSI-191 Closure Options Option 1: Compliance with 10 CFR 50.46 Based on Approved Models • Attributes and Requirements • Ideal for low/no fiber plants that meet “Clean Plant Criteria” or plants that can meet the 15 grams per fuel assembly fiber limit associated with WCAP 16793 r. 2 • Must demonstrate compliance with 10 CFR 50.46 • Must comply with any additional conditions imposed through the anticipated SE for WCAP-16793 r. 2 • Additional margin may be achieved later based on current PWROG testing results • Required plant actions must be completed within two refueling outages after January 1, 2013
GSI-191 Closure Options Option 2: Deterministic or Risk-Informed • Graded approach with actions based on amount of fibrous insulation • Plants must implement defense-in-depth and mitigation measures to offset residual risk while testing and/or modifications are completed (Plants may reference the NEI March 5, 2012 letter to NRC summarizing these measures) • Option 2 offers a deterministic or risk-informed path for resolution and closure
GSI-191 Closure Options Option 2a: Deterministic Resolution Path • Attributes and Requirements • Actions taken based on amount of fibrous insulation • Apply results of new PWROG test program to provide basis for new in-vessel criteria • Anticipate new in-vessel criteria will minimize or eliminate the need for additional plant modifications • Testing and plant modifications are to be completed within three refueling outages after January 1, 2013
GSI-191 Closure Options Option 2b: Full Risk-Informed Resolution Path • Attributes and Requirements • Utilize risk-informed methods piloted by STPNOC-Risk assessment models and plant-specific testing support assumptions • Plant-specific resolution schedule established with NRC • Anticipate license amendment request submitted by December, 2015. • All testing and analysis to support assumptions complete within two RFOs after January 1, 2013 • If risk-informed approach is determined to not be feasible, deterministic resolution will be completed by third RFO after January 1, 2013
GSI-191 Closure Options Option 3 Different Regulatory Treatment for Suction Strainer and In-Vessel Effects • Attributes and Requirements • Separate resolution paths for strainers and in-vessel effects • Strainer resolved deterministically, in-vessel resolved by risk-informed or yet to be defined methods • Requires identification of defense-in-depth measures to mitigate risk while testing, and modifications are completed • Deterministic scope to be complete within two RFOs after January 1, 2013 and the risk-informed scope consistent with the schedule defined by Option 2b. • The NRC is interested in identifying a plant(s) to pilot this conceptually defined option
GSI-191 Industry Workshop Topical Agenda • Thursday October 18th • Introductions and Opening Remarks • NRC Perspectives on Closure • PWROG Closure Plan • PWROG Perspective on Closure • GSI-191 Downstream Effects Resolution Path • GSI-191 Downstream Effects –Alternate Flow Paths • PWROG Closure Plan Panel Discussion w/Q&A • Risk-Informed Approach • Risk-Informed Approach Panel Discussion w/Q&A • Closing Comments
GSI-191 Industry Workshop Topical Agenda • Friday October 19th • Opening Remarks: Agenda Review and Re-focus • Option 3 (Reg. Guide 1.174 and Other Approaches) • Risk-Informing In-Vessel Effects • Risk-Informed Approach for GSI-191 Resolution • Defense-in –Depth, Mitigation Measures • Bypass Testing Attributes and Recent Bypass Testing Results • Bypass Testing • STP Testing with NEI Debris Preparation • Bypass Testing NRC Perspective
GSI-191 Industry Workshop Topical Agenda • Panel Discussion on Closure Strategies w/Q&A • Closing Comments • Template Overview for All Closure Options • Option 1 – Beaver Valley • Option 2a – Farley • Option 2b – Vogtle • Option 3 – Point Beach • Operability Determination Approaches • Assuring Regulatory Certainty Through Technical Specifications • Operability Determination Template