SMiRT 21 November 2011 Advances in Seismic Hazard Assessment for - - PowerPoint PPT Presentation

Advances in Seismic Hazard Assessment for Nuclear Facilities in the Central and Eastern United States

• Dr. Annie Kammerer
• Dr. Jon Ake
• Dr. Cliff Munson

SMiRT 21

November 2011

Source Characterization Ground motion prediction equations Framework for large PSHA studies

Central and Eastern US Seismic

Source Characterization project for Nuclear Facilities (CEUS SSC) Next Generation Attenuation Relationships for the Central and Eastern (NGA-East) Recommendations for Application

• f the SSHAC Guidelines

3 projects that work together

dM . dr ) r , M PGA PGA ( P ). r ( f ). M ( f ) PGA ( E

i n 1 i r M M i i

min max min

> ∑ ∫ ∫ =

= ∞

α

PSHA

CEUS Seismic Source Characterization Project for Nuclear Facilities (SSC) NGA-East

(Ground Motion Characterization)

Rieter, 1991

CEUS SSC Project

• Central and Eastern United States Seismic

Source Characterization for Nuclear Facilities Project

• 4 Year SSHAC Level 3 project to create

new source model for the CEUS

• Model finalized and accepted by the PPRP
• NRC GI-199 draft letter notes CEUS SSC

models as accepted model for reevaluation

5

CEUS SSC Project

• Publically available

in January as an NRC NUREG, EPRI report, and DOE report

• Web site to be

published in February

6

CEUS SSC Project

• Regional model

used as a starting point for all reactors in the study area

• Applicants perform

a SSHAC Level 2 refinement to the model as per RG1.208.

• Appropriate data collection and field

investigation efforts to meet 10 CFR 100.23 requirements Data Collection in RG1.208

Site (>1km) Site Area (>8 km)

Site Vicinity (>40 km) Site Region (>320 km)

Increasing level of effort close to site. However, any seismic sources that may impact hazard should be appropriately assessed. Regional source models (e.g. new CEUS SSC model) must still be refined with site-specific information

8

CEUS SSC Advancements

• Identification of zones of “Repeated Large

Magnitude Events”, principally through advanced paleoseismicity techniques

• State-of-the-art Bayesian Mmax assessments

Source USGS Li et al, 1998

9

CEUS SSC Advancements

• New fully consistent seismicity catalog, with

transparent tracked and documented uncertainties in all conversions

• A new approach to variable a- and b-values

using a “Penalized Likelihood” approach

• Comprehensive GIS database combining all

available datasets

• New Paleoliquefaction Database and new

description of associated “best practice”

10

CEUS SSC Advancements

• New “Data Evaluation” and “Data Summary”

tables to document and summarize all available data, models and methods, and their use in the model

– Example provided in the SSHAC NUREG – Modified for use in the NGA-East and South Africa SSHAC Level 3 projects

NGA-East

• Next Generation Attenuation Relationships

for Central and Eastern North America (participation of Canada & other countries in stable continental regions (SCR))

• SSHAC Level 3 project to be complete 2014
• Managed and led by the Pacific Earthquake

Engineering Research Center at University

• f California, Berkeley

NGA-East

• Extremely complex study requiring a large

amount of research and development

• Global SCR database being collected and

beneficial research for SCRs globally

• New work in geotechnics, source inversion,

and a large number of simulations to complement limited earthquake database

• Data from August 2011 Mineral Virginia

earthquake to be collected

NGA-East

NGA-East

Simplified Flow Chart

• f Activities

NGA-East

Complete Flow Chart

• f Activities

• Complete project plan, videos and

presentations from past workshops, and

• ther documentation available on-line
• http://peer.berkeley.edu/ngaeast/

17

SSHAC Guidelines

• Refer to Presentation on Paper 699
• NUREG supplements NUREG/CR-6372
• NUREG in final publication
• Use of SSHAC guidelines in applications

for new reactors in the US

– New Level 3 regional model to be used for new reactors in the east through CEUS SSC and NGA-East projects. – New reactors in the west must perform a site-specific Level 3 or 4 assessment study due to lack of a regional model

18

Fukushima Lessons Learned Report with Significant Recommendations for changing NRC regulations and practices NRC ML111861807 Fukushima Lessons Learned Report with Recommendations for changing NRC regulations and practices

Recommendation 2.1 Order licensees to reevaluate the seismic and flooding hazards at their sates against current NRC requirements and guidance, and if necessary update the design basis and SSCs important to safety to protect against the updated hazards

NRC ML111861807

19

SSHAC Guidelines

• Re-evaluation of Operating Reactors

– Generic Issue 199 draft letter out for comment (ML111710782) merging with NTTF R2.1 – Existing reactors in the will use the new CEUS SSC model with the 2004, 2006 EPRI ground motion prediction equations – Existing reactors outside of the CEUS SSC study region will be required to perform site- specific SSHAC Level 3 studies. (Diablo Canyon PP is staring this month)

20

SSHAC Guidelines

• For NPPs in the United States

– 2 Ongoing cooperative regional SSHAC Level 3 studies (one complete in December) – 1 SSHAC Level 3 study for a new western site starting imminently – 1 SSHAC Level 3 study for an existing western site starting imminently – 3 additional SSHAC Level 3 or 4 studies for

• perating NPPs are expected for GI-199

Title Goes Here

Thank You

Advances in Seismic Hazard Assessment for Nuclear Facilities in the Central and Eastern United States