ML15155A748
| ML15155A748 | |
| Person / Time | |
|---|---|
| Site: | Columbia  |
| Issue date: | 06/04/2015 |
| From: | Japan Lessons-Learned Division |
| To: | |
| DiFrancesco N, NRR/JLD, 415-1115 | |
| References | |
| Download: ML15155A748 (17) | |
Text
Near-term Task Force Recommendation 2.1 (R2.1)
Seismic Hazard Evaluation Energy Northwest Columbia Generating Station Public Meeting June 4, 2015
References and Logistics
- Public Meeting Agenda - ML15142A452
- NRC Presentation Slides - ML15155A748
- Licensee Presentation Slides - ML15154B396
- Licensee Hazard Report - ML15078A243
- Screening and prioritization results -
- Meeting Feedback Form (request from njd2@nrc.gov)
- Meeting Summary to be issued within 30-day 2
Meeting Purposes
- Gather additional information based on early identification of areas where additional technical information will support the staffs review
- Gain a better understanding of how the licensee conducted their evaluation 3
Outline
- Overview of Recommendation 2.1 -
Response to NRC 50.54(f) letter
- Screening and Prioritization results
- NRC approach to seismic hazard characterization reviews for Western US (WUS) sites
- Review schedules and timeline 4
Seismic R2.1 Process Ensures Clarity, Consistency, and Risk-Informed Regulatory Decisions 5
NRC makes Regulatory Decisions as Needed
- Safety Enhancements
- Backfit Analysis
- Modify Plant License PHASE 2 DECISION-MAKING Interact with Industry on Hazard and Risk Evaluation Guidance CEUS Licensees submit Site Response (9/2013 &
3/2014)
Licensees submit Hazard Reevaluations and Interim Evaluations, as needed (CEUS:3/2014,WUS:3/2015)
Screen and prioritize plants for Risk Evaluation.
Review Interim Evaluations, as needed (CEUS:5/2014; WUS:5/2015)
Screened-in plants complete Expedited Interim Evaluation (CEUS:12/31/2014;WUS:1/2016) and Risk Evaluation (Group 1: 6/2017)
NRC reviews Risk Evaluation PHASE 1 STAGE 1 STAGE 2 INFORMATION GATHERING
Seismic Screening and Prioritization results
- NRC Letter issued for WUS sites on May 13, 2015 (ML15113B344)
- Columbia has screened-in for seismic risk evaluation and limited scope evaluations
- Review Group 1 plant
- No immediate safety issues identified
- Information supports safety assurance allowing additional time to complete the seismic risk evaluation 6
NRC Review of SSHAC Studies for WUS Sites
- Did SSHAC process follow NRC guidance?
- How effective was the peer review panel?
- Have all applicable data been considered?
- Were data uncertainties identified and considered?
- Was an appropriate range of applicable models considered?
- How were models selected and weighted in the analysis?
- How were models assembled into the PSHA?
7
NRC Review of Source Models for WUS Sites
- How were seismic sources identified?
- Geologic mapping
- Geophysical observations
- Earthquake catalog
- How were seismic sources characterized?
- Geometry (location, length, dip)
- Range of magnitudes
- Faulting style (normal, reverse, strike-slip)
- Slip rate and recurrence models
- Complex rupture scenarios 8
NRC Review of Ground Motion Models and Site Response for WUS Sites
- Do final ground motion models capture a reasonable range of alternative models?
- How were sources of uncertainty captured in model development?
- How were ground motion models adjusted for local site geology?
- Does site response analysis cover a reasonable range of alternative soil/rock properties?
- How was uncertainty in site response analysis incorporated into final probabilistic hazard curves?
9
WUS Hazard Staff Review Timeline
- March 2015: WUS Hazard Submittals
- May: Screening and prioritization letter
- June/July: Public meetings
- Late summer/early fall: Staff questions
- December: GMRS suitability Letter
- January 2016: ESEP Interim Evaluation
- April 2016: ESEP review response
- Summer 2016: Document Hazard review
- June 2017: Risk Evaluation submittal (Grp 1) 10
Break for NRC Staff Alignment
- 15 - 20 minute planned break for NRC staff alignment to support meeting wrap-up
- Meeting to resume at 3:00pm (Eastern) or 12:00pm (Western) 11
Opportunity for Public Questions or Comments
- Additional Questions?
Please ask us at:
JLD_PublicResource@nrc.gov 12
List of Acronyms CEUS - Central and Eastern United States ESEP - Expedited Seismic Evaluation Process (for Interim Evaluation)
GMRS - Ground Motion Response Spectrum NRC - U.S. Nuclear Regulatory Commission NPP - Nuclear Power Plant NTTF - Near-Term Task Force PSHA - Probabilistic Seismic Hazard Analysis SFP - Spent Fuel Pool SMA - Seismic Margins Analysis SPID - Screening, Prioritization, and Implementation Details SPID SPRA - Seismic Probabilistic Risk Assessment SSC - Structures, Systems and Components SSHAC - Senior Seismic Hazard Analysis Committee SSE - Safe Shutdown Earthquake SPID - Screening, Prioritization, and Implementation Details WUS - Western United States 13
Backup Slides 14
Additional WUS Seismic Hazard Reports Public SSHAC Report
- Hanford Sitewide (PSHA including Columbia Generating Station) http://www.hanford.gov/page.cfm/OfficialDo cuments/HSPSHA 15
Guidance Documents
- Two main guidance documents proposed by industry and endorsed by the NRC
- Screening, Prioritization, and Implementation Details (SPID)
- Submitted by EPRI on November 2012
- Endorsed by NRC on February 15, 2013
- EPRI-1025287 (ML12333A170)
- Seismic Evaluation Guidance: Augmented Approach (aka Expedited Approach)
- Submitted by EPRI on April 9, 2013
- Endorsed by NRC on May 7, 2013
- EPRI-3002000704 (ML13102A142) 16
2012 2013 2014 2015 2016 2017 2018 2019 2020 Hazard Development Expedited Interim Evaluations Risk Evaluations Higher Priority Lower Priority CEUS CEUS Group 1 Only plants with new seismic hazard exceeding design basis All plants Hazard Analyses WUS Group 3 (as needed)
WUS Group 2 Risk Evaluations plant mods plant mods Staff Assessment or response Staff acknowledgement to use GMRS for risk evaluation Expedited Interim Evaluations Schedule for Seismic Hazard and Risk Evaluations 17