epri (2004, 2006) ground-motion model (gmm) review projectepri (2004, 2006) ground-motion model...

EPRI (2004, 2006) Ground-MotionModel (GMM) Review Project3002000717

Final Report June 2013

Electric Power Research Institute3420 Hillview AvenuePalo Alto, CA 94304

J. F. HamelExecutive Director

R. P. KassawaraSenior Project Manager

This document was not developed under a 1OCFR50Appendix B program.

DISCLAIMER OF WARRANTIES AND LIMITATION OF LIABILITIES

THIS DOCUMENT WAS PREPARED BY THE ORGANIZATION(S) NAMED BELOW AS ANACCOUNT OF WORK SPONSORED OR COSPONSORED BY THE ELECTRIC POWER RESEARCHINSTITUTE, INC. (EPRI). NEITHER EPRI, ANY MEMBER OF EPRI, ANY COSPONSOR, THEORGANIZATION(S) BELOW, NOR ANY PERSON ACTING ON BEHALF OF ANY OF THEM:

(A) MAKES ANY WARRANTY OR REPRESENTATION WHATSOEVER, EXPRESS OR IMPLIED, (I)WITH RESPECT TO THE USE OF ANY INFORMATION, APPARATUS, METHOD, PROCESS, ORSIMILAR ITEM DISCLOSED IN THIS DOCUMENT, INCLUDING MERCHANTABILITY AND FITNESSFOR A PARTICULAR PURPOSE, OR (11) THAT SUCH USE DOES NOT INFRINGE ON ORINTERFERE WITH PRIVATELY OWNED RIGHTS, INCLUDING ANY PARTY'S INTELLECTUALPROPERTY, OR (Il) THAT THIS DOCUMENT IS SUITABLE TO ANY PARTICULAR USER'SCIRCUMSTANCE; OR

(B) ASSUMES RESPONSIBILITY FOR ANY DAMAGES OR OTHER LIABILITY WHATSOEVER(INCLUDING ANY CONSEQUENTIAL DAMAGES, EVEN IF EPRI OR ANY EPRI REPRESENTATIVEHAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES) RESULTING FROM YOURSELECTION OR USE OF THIS DOCUMENT OR ANY INFORMATION, APPARATUS, METHOD,PROCESS, OR SIMILAR ITEM DISCLOSED IN THIS DOCUMENT.

REFERENCE HEREIN TO ANY SPECIFIC COMMERCIAL PRODUCT, PROCESS, OR SERVICE BY ITSTRADE NAME, TRADEMARK, MANUFACTURER, OR OTHERWISE, DOES NOT NECESSARILYCONSTITUTE OR IMPLY ITS ENDORSEMENT, RECOMMENDATION, OR FAVORING BY EPRI.

THE FOLLOWING ORGANIZATION(S), UNDER CONTRACT TO EPRI, PREPARED THIS REPORT:

AMEC Environment & Infrastructure, Inc.

Earthquake Hazards Solutions

Lettis Consultants International, Inc.

Virginia Tech, Department of Geosciences

Workforcelogic, LLC

III

ACKNOWLEDGMENTS

The following organizations, under contract to the Electric Power Research Institute (EPRI),prepared this report:

Workforcelogic, LLC420 S. Orange AvenueOrlando, FL 32801

Technical Project ManagerSalomone, L.A.

Lettis Consultants International, Inc.3 Farmers RowActon, MA 01720

Principal InvestigatorToro, G.R.

AMEC Environment & Infrastructure, Inc.2101 Webster St., 12th FloorOakland, CA 94612

Principal InvestigatorYoungs, R.R.

Lettis Consultants International, Inc.4155 Darley Ave., Suite ABoulder, CO 80305

Principal InvestigatorMcGuire, R.K.

Virginal Tech, Department of Geosciences4044 Derring HallBlacksburg, VA 24061

Principal InvestigatorChapman, M.

IV

Earthquake Hazards Solutions871 Chimney Valley RoadBlanco, TX 78606

Senior Technical AdvisorStepp, J.C.

Lettis Consultants International, Inc.1981 N. Broadway, Suite 330Walnut Creek, CA 94596

Database ManagerBozkurt, S.B.

This report describes research sponsored by EPRI.

EPRI would also like to acknowledge the Participatory Peer Review Panel (W. Arabasz -Chairman, B. Chiou, R. Quittmeyer, and R. Whorton), who reviewed the technical and processaspects of the project, and GEOVision, Inc., with The University of Texas, who conducted theshear-wave-velocity measurements at seismic recording stations. The ground-motion experts andseismologists, listed in Table 2.1-1, who participated in the due diligence review of the EPRI(2004, 2006) Ground-Motion Model, in interviews conducted by the TI Team (Appendix C), andin the October 17, 2012, workshop (Table 2.2.6-1) are also acknowledged. The value of theUpdated EPRI (2004, 2006) GMM has been enhanced through productive cooperation from thePacific Earthquake Engineering Research (PEER) Center, members of the NGA-East Project,and the U.S. Geological Survey (USGS). Some of the analyses and graphics contained in thisreport were prepared using R (R Development Core Team, 2012). EPRI thanks R. Chambers, G.Moore, and N. Sutherland of AMEC Environment & Infrastructure, Inc., for their assistance withthe preparation of the report.

ABSTRACT

This report describes the Electric Power Research Institute (EPRI) (2004, 2006) Ground-MotionModel (GMM) Review Project, which developed an updated GMM for the Central and EasternUnited States (CEUS) for use by licensees of nuclear generating plants to respond to the U.S.Nuclear Regulatory Commission's (NRC's) Request for Information to Title 10 of the Code ofFederal Regulations 50.54(f), Recommendation 2.1 of the Near-Term Task Force Review ofInsights from the Fukushima Dai-Ichi Accident, dated March 12, 2012.

The scope of this study was to determine whether the currently accepted existing EPRI (2004,2006) GMM required updating, considering currently available data and seismologicalunderstanding of ground motions in the CEUS, and if determined to require updating, to updatethe model using accepted current practice contained in present-day NRC's seismic regulatoryguidance. The team assembled to conduct the study was composed of distinguished subject-matter experts from industry, government, and academia. The study was carried out properlyusing a Senior Seismic Hazard Analysis Committee (SSHAC) Level 2 process and the activitiesof evaluation and integration, the principal activities of any SSHAC study, were carried outproperly and documented thoroughly. The activities of evaluation considered present-day data,models, and methods. The activities of integration captured the center, body, and range oftechnically defensible interpretations informed by the evaluation process (i.e., informed byevaluations of existing data, models, and methods).

The project solicited and evaluated inputs from recognized experts in the larger technicalcommunity, obtained ongoing process and technical review by a participatory peer review panel(PPRP), and solicited feedback from staff of the NRC throughout the study. The resultingUpdated EPRI (2004, 2006) GMM is thus based on a comprehensive and traceable process,implemented in accordance with SSHAC guidelines in NUREG/CR-6372, Recommendations forProbabilistic Seismic Hazard Analysis: Guidance on Uncertainty and Use of Experts.Considering current NRC guidance for updating an accepted existing hazard model, contained inNUREG-2117, Practical hnplementation Guidelines for SSHA C Level 3 and 4 Hazard Studies;the study used an enhanced SSHAC Level 2 assessment process. Therefore, the updated modelcan be used with confidence to calculate ground-motion response spectra at existing nuclearpower plant (NPP) sites with assurance that the spectra properly represent current technicalknowledge.

The study was conducted in two phases. Phase 1 consisted of assembling an up-to-date databaseand determining whether the EPRI (2004, 2006) GMM should be updated, and Phase 2 consistedof updating the EPRI (2004, 2006) GMM by integrating up-to-date data, models, and methods.As part of the project, shear-wave-velocity measurements were made at 33 seismic recordingstations. In addition, the U.S. Geological Survey provided shear-wave-velocity measurements at24 seismic recording stations. The project also obtained shear-wave-velocity profiles compiled

from the literature available in the NGA-East profile database. These shear-wave-velocity datawere used to establish uniform reference conditions for evaluating ground-motion-predictionequations (GMPEs). The study established the technical basis for evaluating GMPEs and forupdating the EPRI (2004, 2006) GMM by reviewing the current literature and conductinginterviews and a workshop with ground-motion experts and seismologists. The study alsodeveloped the analytical approach for adjusting ground motions to CEUS reference-rockconditions. Computation of GMPE weights using empirical site class factors was an importantpart of the study, along with the update of the EPRI (2006) aleatory variability model based onresults from NGA-West 1 (2008) and the NGA-West 2 (2012) studies.

The decision to proceed with the update of the EPRI (2004, 2006) GMM was based on thefollowing information obtained during the Phase 1 review:

" Seven of the 13 developers of the GMPEs evaluated for development of the EPRI (2004,2006) GMM now recommend that their GMPEs be replaced.

* Three new GMPEs were developed by ground-motion experts during the past 10 years.

" Eighty percent of the earthquake records in a new ground-motion database provided by theNGA-East Project are from earthquakes that occurred after the development of the EPRI(2004) GMM.

" The EPRI (2004, 2006) GMM was determined to over predict ground motions at somemagnitude-distance and spectral frequency ranges important to NPP probabilistic seismichazard assessments (PSHAs).

Computation of ground-motion response spectra for existing NPPs in the CEUS to supportlicensees' responses to the NRC's 50.54(f) letter dated March 12, 2012 requires use of present-day seismic regulatory guidance. This includes use of up-to-date, well-founded ground-motionand seismic-source models. The EPRI/DOE/NRC (2012) CEUS SSC model provides therequired up-to-date seismic source model. Phase 2 of the study updated the EPRI (2004, 2006)GMM providing an up-to-date GMM for calculation of the GMRS at existing NPPs in theCEUS. The EPRI (2004, 2006) GMM was updated for both the Midcontinent and Gulf Regions.

The updated model was obtained through a structured evaluation of the range of diversetechnical interpretations from the larger technical community and a full assessment andincorporation of uncertainties using an up-to-date database. Using the Updated EPRI (2004,2006) GMM, test seismic hazard results for rock conditions were computed at the seven CEUStest sites for which test hazard results were computed as part of the EPRIIDOE/NRC (2012)CEUS SSC study. The hazard results obtained using the updated model were compared with thethose developed in the 2012 CEUS SSC study, which used the EPRI (2004, 2006) GMM. Theuse of the Updated EPRI (2004, 2006) GMM, combined with the 2012 CEUS SSC model,resulted in reductions in seismic hazard at all frequencies except peak ground acceleration. TheUpdated EPRI (2004, 2006) GMM described in this report is suitable for use by licensees fordevelopment of responses the NRC's 50.54(f) letter and should be considered for other seismicregulatory purposes pending completion of the NGA-East Project.

VIII

Keywords

ground-motion model (GMM)

ground-motion prediction equations (GMPEs)

probabilistic seismic hazard analysis (PSHA)

Central and Eastern United States (CEUS)

CONTENTS

ABSTRACT ............................................................................................................................. VII

CONTENTS .............................................................................................................................. XI

1 CHAPTER 1 INTRODUCTION .............................................................................................. 1-1

1.1 Background and History ............................................................................................. 1-1

1.1.1 Context of the Study .......................................................................................... 1-1

1.1.2 Present-Day NRC Seismic Regulatory Requirements and Guidance ................. 1-2

1.1.3 EPRI (2004) GMM and EPRI (2006) Update of Sigma Model-The EPRI(2004, 2006) GMM ............................................................................................ 1-3

1.1.4 NRC Guidance for Updating Seismic Hazard Models ........................................ 1-4

1.2 Purpose of the EPRI (2004, 2006) GMM Review Project ........................................... 1-5

1.3 Study Region ............................................................................................................. 1-5

1.4 Products of the Project ............................................................................................... 1-6

1.4.1 Project Plan ....................................................................................................... 1-6

1.4.2 Updated EPRI (2004, 2006) GMM ..................................................................... 1-6

1.4.3 Hazard Input Document ..................................................................................... 1-7

1.4.4 Documentation of Literature Reviews and Expert Interviews ............................. 1-7

1.4.5 Documentation of PPRP and Observer Comments ........................................... 1-7

1.4.6 Project Database ............................................................................................... 1-8

1.4.7 Shear-Wave-Velocity Measurement at Seismic Recording StationsD ata ba se ........................................................................................................... 1-8

2 CHAPTER 2 PROJECT PLAN ............................................................................................. 2-1

2.1 Due Diligence (October 2011 to March 2012) ............................................................ 2-1

2.2 W ork Plan (March 2012 to June 2012) ....................................................................... 2-3

2.2.1 Task 1--Development of Project Plan and Approval by Participatory PeerReview Panel and NRC Observers .................................................................... 2-4

2.2.2 Task 2-Obtain Ground-Motion Database and Identify New CEUSG M P E s .............................................................................................................. 2 -4

XI

2.2.3 Task 3-Obtain Shear-Wave-Velocity Measurements at SeismicR ecording S tations ............................................................................................ 2-5

2.2.4 Task 4-Test EPRI (2004, 2006) GMM ............................................................. 2-5

2.2.5 Task 5- Update EPRI (2004, 2006) GMM ......................................................... 2-5

2.2.6 Task 6-Workshop: Interactions with Technical Community .............................. 2-6

2.2.7 Task 7- Calculate Seismic Hazard at Seven Demonstration Sites .................... 2-7

2.2.8 Task 8- Finalize Updated EPRI (2004, 2006) GMM .......................................... 2-7

2.2.9 Task 9-Document EPRI (2004, 2006) GMM Review Project in DraftR e p o rt ............................................................................................................... 2 -7

2.2.10 Task 10-- Review Draft Report by PPRP ............................................................ 2-8

2.2.11 Task 11- Finalize Report for the EPRI (2004, 2006) GMM Review Project ....... 2-8

2.2.12 Task 12- Issue Report for the EPRI (2004, 2006) GMM Review Project ........... 2-8

2.2.13 Project Manager (PM) and Technical Integration (TI) Team Evaluationand Integration Working Meetings and Conference Calls .................................. 2-8

3 CHAPTER 3 IMPLEMENTATION OF PRESENT-DAY SEISMIC REGULATORY

GUIDANCE FOR THIS STUDY ............................................................................................... 3-1

3.1 Goals and Activities of a SSHAC Assessment Process .............................................. 3-2

3.2 P roject O rganization ................................................................................................... 3-2

3.2.1 Project Sponsor: EPRI Management ................................................................. 3-3

3.2 .2 P roject M anager ................................................................................................ 3-3

3.2.3 Participatory Peer Review Panel ....................................................................... 3-4

3.2.4 Technical Integration Team ............................................................................... 3-5

3.2.5 Database Manager ............................................................................................ 3-5

3.2.6 Senior Technical Advisors ................................................................................. 3-6

3 .2 .7 O bserve rs .......................................................................................................... 3-6

3.2.8 Other Project Participants: Experts and Specialty Contractors ........................... 3-6

3.3 Project Lines of Communication and Points of Contact .............................................. 3-7

3.4 Evaluation and Integration Activities ........................................................................... 3-7

3.4.1 Development of the Project Database ............................................................... 3-7

3.4.2 Identification of Significant issues ...................................................................... 3-8

3 .4 .3 W orksho p ........................................................................................................... 3-8

3.4 .4 W orking M eetings .............................................................................................. 3-8

3.4.5 Development of the Preliminary Updated Model ................................................ 3-9

3.4.6 Completion and Review of Draft and Final Versions of the UpdatedG round-M otion M odel ........................................................................................ 3-9

3.5 D ocum entation ........................................................................................................ 3-10

XII

3.5.1 Development of the Hazard Input Document ................................................... 3-10

3.5.2 Development of the Draft Project Report ......................................................... 3-10

3.5.3 Review of the Draft Project Report ................................................................... 3-11

3.5.4 Development of the Final Project Report ......................................................... 3-12

3.6 Participatory Peer Review Panel .............................................................................. 3-12

3.6.1 Roles and Responsibilities ............................................................................... 3-12

3.6.2 Reviews and Feedback ................................................................................... 3-12

3.6.3 PPRP Review of Both Technical and Process Issues ...................................... 3-13

4 CHAPTER 4 RESULTS: SHEAR-WAVE-VELOCITY MEASUREMENTS AT SEISMIC

RECORDING STATIONS ........................................................................................................ 4-1

4.1 Technical Approach ................................... .............................................. 4-2

4.2 Discussion and Results .............................................................................................. 4-2

4.3 Observations .............................................................................................................. 4-4

4.4 USGS Shear-W ave-Velocity Data .............................................................................. 4-4

4.5 Use of Shear-W ave-Velocity Data .............................................................................. 4-4

5 CHAPTER 5 EPRI (2004, 2006) GROUND-MOTION MODEL (GMM): OVERVIEW OF

KEY FEATURES ..................................................................................................................... 5-1

5.1 EPRI (2004) GMM Framework ................................................................................... 5-1

5.1.1 Historical Background ........................................................................................ 5-1

5.1.2 Grouping GMPEs into Clusters .......................................................................... 5-2

5.1.3 Methodology Steps ............................................................................................ 5-2

5.1.4 Adjustment for Gulf Coast Region ...................................................................... 5-3

5.2 EPRI (2004) Aleatory Model Studies .......................................................................... 5-3

5.3 EPRI (2006) Aleatory Model Study ............................................................................. 5-4

6 CHAPTER 6 EVALUATION OF THE EPRI (2004, 2006) GMM IN LIGHT OF NEW

DATA, MODELS, AND METHODS ......................................................................................... 6-1

6.1 Compilation of Initial Project Database ....................................................................... 6-1

6.1.1 Initial Ground-Motion Database ......................................................................... 6-1

6.1.2 Shear-Wave-Velocity Measurements at Seismic Recording Stations ................. 6-2

6.2 Summary and Evaluation of Available GMPEs for CENA ........................................... 6-3

6.2.1 Summary and Evolution of GMPEs Used in EPRI (2004) GMM ......................... 6-3

6.2.2 New Candidate GMPEs ..................................................................................... 6-5

6.2.3 Evaluation of Candidate GMPEs ....................................................................... 6-7

6.3 Adjustment for Recording-Site Conditions .................................................................. 6-8

XIII

6.3.1 Analytical Adjustment for Recording-Site Condition ........................................... 6-9

6.3.2 Empirical Adjustment for Recording-Site Conditions ........................................ 6-10

6.4 Test of EPRI (2004, 2006) GMM: Comparisons of Observations to GMMP re d ictio n s ................................................................................................................. 6-1 1

6.4.1 Comparisons Using Analytical Adjustment for Recording-Site Conditions ........ 6-11

6.4.2 Comparisons Using Empirical Adjustment for Recording-Site Conditions ........ 6-11

6.5 New Information for Aleatory Variability .................................................................... 6-12

6.6 Conclusions from Comparisons ................................................................................ 6-12

6 .6 .1 B ia s ................................................................................................................. 6 -12

6.6.2 E pistem ic U ncertainty ...................................................................................... 6-13

6.7 Decision Point 2 - Basis for Proceeding with Updating the EPRI (2004, 2006)G M M ................................................. . ....................................................................... 6 -13

6.7.1 PPRP Feedback ........................................... 6-13

6.7.2 EPRI Communication to Nuclear Regulatory Commission ............................... 6-14

7 CHAPTER 7 UPDATED EPRI (2004, 2006) GMM ............................................................. 7-1

7.1 General Methodology for Updating EPRI (2004, 2006) GMM ..................................... 7-1

7.1.1 O verview and Road M ap ................................................................................... 7-1

7.1.2 Data and Data-Selection Criteria ....................................................................... 7-2

7.1.3 O verall Structure of G M M .................................................................................. 7-3

7.1.4 Model for Aleatory Uncertainty ........................................................................... 7-3

7.2 Development of Final Ground-Motion Database ......................................................... 7-3

7.2.1 Ground-Motion Data Sources ................................... 7-4

7.2.2 Ground-Motion Record Processing .................................................................... 7-5

7.2.3 Assignment of Moment Magnitude ................................................................... 7-7

7.2.4 Estimation of Rupture and Joyner-Boore Distance Measures ............................ 7-7

7.2.5 Classification of Recording Station Site Conditions ............................................ 7-9

7.2.6 Distribution of Final Database ........................................................................ 7-10

7.3 Adjustment for Recording-Site Conditions ................................................................ 7-11

7.3.1 Analytical Adjustment for Recording-Site Condition ......................................... 7-12

7.3.2 Empirical Adjustment for Recording-Site Condition .......................................... 7-17

7.3.3 Comparison of Analytical and Empirical Approaches ....................................... 7-19

7.4 Technical Bases for GMPEs and Development of Final Clusters ............................. 7-19

7.4.1 Selection of GMPEs and Specification of Cluster Groupings ........................... 7-20

7.4.2 Consideration of Regional Differences ............................................................. 7-22

7.4.3 Approach for the Calculation of Within-Cluster Weights ................................... 7-24

XIV

7.4.4 Development of W ithin-Cluster Epistemic Uncertainty ..................................... 7-29

7.4.5 Development of Cluster W eights ..................................................................... 7-31

7T5 Calculation of W ithin-Cluster W eights ...................................................................... 7-32

7.5.1 Calculation of Within-Cluster Weights Based on Analytical SiteA djustm e nts .................................................................................................................. 7-32

7.5.2 Calculation of Within-Cluster Weights Based on Empirical SiteAdjustments ..................................................................................................... 7-33

7.5.3 Results for W ithin-Cluster W eights .................................................................. 7-34

7T6 Cluster Median GM Models for the Midcontinent ...................................................... 7-35

7.6.1 Conversion from Rupture to Joyner-Boore Distance ........................................ 7-35

7.6.2 Calculation of Cluster Median GMMs ............................................................... 7-35

7.7 Overall Epistemic Uncertainty for Each Cluster and Calculation of High and LowGMMs for the Midcontinent ......................................................................................... 7-36

7.7.1 Development of W ithin-Cluster Epistemic Uncertainty ..................................... 7-37

7.7.2 Development of GMPEs to Represent Within-Cluster EpistemicU nce rta inty ...................................................................................................... 7-4 1

7.8 Adjustments from Epicentral Distance to Joyner-Boore Distance ............................. 7-41

7.8.1 Distance Adjustment ........................................................................................ 7-41

7.8.2 Additional Aleatory Variability .......................................................................... 7-42

7.9 Cluster W eights ........................................................................................................ 7-43

7.9.1 Calculation of Data-Consistency Cluster Weights Based on Analytical SiteAdjustments ..................................................................................................... 7-43

7.9.2 Calculation of Data-Consistency Cluster Weights Based on Empirical SiteAdjustments ..................................................................................................... 7-44

7.9.3 Results for Cluster W eights ............................................................................. 7-44

7.10 Updated EPRI (2006) Aleatory Variability Model .................................................. 7-46

7.10.1 Approach for Specification of Aleatory Variability Model ............................... 7-46

7.10.2 Updated Aleatory Variability Model ............................................................... 7-48

7.11 Development of Alternate Set of Median GMPEs for the Gulf Coast .................... 7-50

7.11.1 Basis for Defining Gulf Coast Region ........................................................... 7-50

7.11.2 Modification of Midcontinent GMM for Application to Gulf Coast CrustalR e g io n ............................................................................................................ 7 -5 5

7.12 Comparison with EPRI (2004, 2006) GMM and Other Models ............................. 7-58

7.12.1 Comparison with EPRI (2004, 2006) GMM ................................................... 7-58

7.12.2 Comparison with Atkinson et al. (2012) ........................................................ 7-59

7.12.3 Comparison with NGA for W NA .................................................................... 7-60

7.13 Sensitivity Analyses ............................................................................................. 7-60

xv

7.13.1 Effect of G iving Zero W eight to Data w ith M < 4.75 ...................................... 7-61

7.13.2 Effect of Down-W eighting O klahom a-Arkansas Data .................................... 7-61

7.13.3 Effect of Considering Only 10 Hz and 1 Hz Weights for Within-ClusterW eights ........................................................................................................... 7-62

7.13.4 Effect of Alternative Approach for Calculation of Within-Cluster Weights ..... 7-62

7.14 Discussion of Updated G M M ............................................................................... 7-62

7.15 Hazard Input Docum ent ....................................................................................... 7-63

7.15.1 Overview ...................................................................................................... 7-63

7.15.2 Contents of the Hazard Input Docum ent ....................................................... 7-64

8 CHAPTER 8 DEMONSTRATION HAZARD CALCULATIONS ............................................. 8-1

8.1 Background on Dem onstration Hazard Calculations .................................................. 8-1

8.2 Dem onstration Hazard Calculations ........................................................................... 8-2

8.2.1 Central Illinois Site ............................................................................................. 8-3

8.2.2 Chattanooga Site ............................................................................................... 8-3

8.2.3 Houston Site ...................................................................................................... 8-3

8.2.4 Jackson Site ...................................................................................................... 8-4

8.2.5 M anchester Site ................................................................................................. 8-4

8.2.6 Savannah Site ................................................................................................... 8-5

8.2.7 Topeka Site ....................................................................................................... 8-5

8.2.8 Com parison of Hazard by Equation ................................................................... 8-5

9 CHAPTER 9 REFERENCES ................................................................................................ 9-1

10 CHAPTER 10 G LO SSARY O F KEY TERM S .................................................................. 10-1

A DESCRIPTION OF PROJECT DATABASE

A.1 Data Sources ............................................................................................................... A-2

A.2 Project Database Design and Managem ent ................................................................. A-2

A.3 W orkflow and Data Assessm ent ................................................................................... A-4

A.3.1 W orkflow ............................................................................................................... A-4

A.3.2 Data Assessm ent ................................................................................................. A-4

A.4 Use of Project Database in M odel Developm ent ..................................................... A-5

A.5 M etadata ...................................................................................................................... A-5

A.6 G round-M otion Database ............................................................................................. A-6

A.6.1 G round-M otion Flat File ........................................................................................ A-6

XV1

A.6.2 Earthquakes ......................................................................................................... A-7

A.6.3 Recording Stations ............................................................................................... A-8

A.6.4 Analytically Adjusted G round-M otion Flat File ....................................................... A-9

A.6.5 Shear-W ave-Velocity Profile Files and Tem plate Profiles ..................................... A-9

B DOCUMENTATION FOR LITERATURE REVIEWS

B.1 Introduction .................................................................................................................. B-1

B.2 Literature Reviewed .................................................................................................. B-1

B.3 Literature Review Tables .............................................................................................. B-3

C DOCUMENTATION FOR INTERVIEWS

C. Introduction ................................................................................................................. C-1

C.2 Experts Interviewed ................................................................................................. C-1

C.3 Questions Posed to Resource and Proponent Experts ........................................... C-2

C.4 Interview Tables ........................................................................................................... C-3

D COMMENT RESPONSE TABLES AND OTHER PPRP AND OBSERVER FEEDBACK

D.1 Introduction .................................................................................................................. D-1

D.2 Com m ent Response Tables ......................................................................................... D-2

D.3 Slide Presentations .................................................................................................. D-2

E WORKING MEETINGS AND WORKSHOP

E.1 Docum entation of W orking Meetings and W orkshop ............................................... E-1

F BIOGRAPHIES OF PROJECT TEAM

F.1 EPRI Managem ent .................................................................................................... F-1

F.2 Project M anager ........................................................................................................... F-1

F.3 TI Team ........................................................................................................................ F-2

F.4 Technical Support ........................................................................................................ F-4

F.5 Database M anager ....................................................................................................... F-5

F.6 Participatory Peer Review Panel .................................................................................. F-6

G HAZARD INPUT DOCUMENT

G .1 Overview ..................................................................................................................... G-1

G .2 Hazard Input Docum ent ........................................................................................... G-1

G .2.1 Cluster and Curve W eights .............................................................................. G-1

G .2.2 Definition of M idcontinent and G ulf Regions .................................................... G-1

XvII

G.2.3 Functional Form of GMPEs (Midcontinent and Gulf) ............................................ G-2

G.2.4 Functional Form and Associated Sigma for Conversion from Epicentral Distance toR JB ........................................................................................................................ G -3

G.2.5 Aleatory Uncertainty ............................................................................................. G-4

G .3 U ser Instructions .......................................................................................................... G -4

G.3.1 Range of Applicability ........................................................................................... G-5

G.3.2 Midcontinent vs. Gulf Regions .............................................................................. G-5

G.3.3 Use of Cluster 4 GMPEs ...................................................................................... G-5

G.3.4 Electronic Attachments ......................................................................................... G-6

H CORRESPONDENCE

H.1 EPRI Decision Point 2 Letter to Nuclear Regulatory Commission (NRC) August2 4 , 2 0 12 ...................................................................................................................... H -2

H.2 PPRP GMM Report #1 (Project Plan) April 20, 2012 .................................................... H-4

H.3 PPRP GMM Report #2 (Decision Point 2) August 20, 2012 ....................................... H-2.8

H.4 PPRP GMM Report #3 (Feedback Workshop) October 23, 2012 ............................... H-33

H.5 PPRP GMM Report #4 (PPRP Closure Briefing Action Items) March 6, 2013 ............ H-38

H.6 PPRP GMM Report #5 (GMM PPRP Closure) April 5, 2013 ...................................... H-59

H.7 PPRP GMM Report #6 (Review of Draft Project Report) May 21, 2013 ..................... H-64

I QUALITY ASSURANCE

1.1 B a ckg ro u nd .................................................................................................................... I-1

1.2 EPRI (2004, 2006) GMM Review Project ........................................................................ 1-2

1.3 B usiness B est P ractices ................................................................................................. 1-3

1.4 Approach for Adjusting Ground Motions to Reference Rock Conditions ......................... 1-3

1.5 Update of EPRI (2006) Aleatory Variability Model ........................................................... 1-4

1.6 Hazard Calculation Software ......................................................................................... 1-4

EXECUTIVE SUMMARY ........................................................................................................ XLI

PPRP FINAL REPORT #7 EPRI GMM REVIEW PROJECT .................................................. LVII

ABBREVIATIONS AND SYMBOLS ..................................................................................... LXIV

XVIll

LIST OF TABLES

Table 2.1-1 Industry Due Diligence Review-Participant Acknowledgments ............................ 2-9

Table 2.2.6-1 Technical Community Resource Experts and Proponents at October 17,20 12 , W o rkshop ............................................................................................................. 2-10

Table 2.2.13-1 Technical Meetings and Conference Calls Conducted as Part of the EPRI(2004, 2006) GMM Review Project ................................................................................. 2-11

Table 4-1 Locations of Seismic Recording Stations in the Central and Eastern U.S ................. 4-6

Table 4.2-1 Shear-Wave-Velocity Investigation Results ........................................................... 4-8

Table 4.4-1 Shear-Wave-Velocity Results - USGS Stations .................................................... 4-9

Table 4.4-2 USGS Station Locations ...................................................................................... 4-10

Table 5.1.2-1 EPRI (2004) Models Grouped by Cluster ........................................................... 5-6

Table 7.2.3-1 (page 1 of 7) Moment Magnitudes for Earthquake in Ground-MotionD ata ba se ................................................. ...................................................................... 7-65

Table 7.2.3-1 (page 2 of 7) Moment Magnitudes for Earthquake in Ground-MotionD a ta b a se ........................................................................................................................ 7 -6 6

Table 7.2.3-1 (page 3 of 7) Moment Magnitudes for Earthquake in Ground-MotionD a ta ba se ........................................................................................................................ 7 -6 7

Table 7.2.3-1 (page 4 of 7) Moment Magnitudes for Earthquake in Ground-MotionD ata ba se ........................................................................................................................ 7 -6 8

Table 7.2.3-1 (page 5 of 7) Moment Magnitudes for Earthquake in Ground-MotionD a ta b a se ........................................................................................................................ 7 -6 9

Table 7.2.3-1 (page 6 of 7) Moment Magnitudes for Earthquake in Ground-MotionD a ta ba se ........................................................................................................................ 7 -7 0

Table 7.2.3-1 (page 7 of 7) Moment Magnitudes for Earthquake in Ground-MotionD ata b a se ........................................................................................................................ 7 -7 1

Table 7.2.6-1 Number of Earthquakes in Final Ground-Motion Database Used toDevelop Ground-Motion Model Weights ......................................................................... 7-72

Table 7.2.6-2 Number of Rock Site Recordings in Final Ground-Motion Database Usedto D evelop G M M W eights ............................................................................................... 7-73

Table 7.2.6-3 Number of Recording Stations in Final Ground-Motion Database Used toD evelop G M M W eights ................................................................................................... 7-74

Table 7.2.6-4 Number of Recording Stations with Measured Vs in Final Ground-MotionDatabase Used to Develop GMM Weights ..................................................................... 7-75

Table 7.3.1.1-1 (page 1 of 3) Stations with Shear-Wave-Velocity Profiles .............................. 7-76



Table 7.3.1.1-2 Reference Shear-Wave-Velocity Profile ........................................................ 7-79

Table 7.4.1-1 Updated EPRI (2004, 2006) GMM Clusters and Models .................................. 7-80

Table 7.4.2-1 (page 1 of 2) Results of Statistical Analysis of Regionalization ......................... 7-81

Table 7.4.2-1 (page 2 of 2) Results of Statistical Analysis of Regionalization ......................... 7-82

Table 7.5.2-1 Soft Rock Scaling Factors Used for Empirical Site Adjustments ...................... 7-83

xix

Table 7.5.3-1 Calculation of GMPE Weights for Cluster 1, 25 Hz Spectral Acceleration,Using the Analytical Adjustment for Site Conditions ....................................................... 7-84

Table 7.5.3-2 Calculation of GMPE Weights for Cluster 1, 25 Hz Spectral Acceleration,Using the Empirical Adjustment for Site Conditions ........................................................ 7-84





Table 7.5.3-7 Calculation of GMPE Weights for Cluster 1, 2.5 Hz Spectral Acceleration,Using the Analytical Adjustment for Site Conditions ....................................................... 7-87

Table 7.5.3-8 Calculation of GMPE Weights for Cluster 1, 2.5 Hz Spectral Acceleration,Using the Empirical Adjustment for Site Conditions ........................................................ 7-87





Table 7.5.3-13 Combination of GMPE Weights for Cluster 1 .................................................. 7-90










xx




Table 7.5.3-26 Combination of GMPE Weights for Cluster 2 .................................................. 7-97





Table 7.5.3-31 Calculation of GMPE Weights for Cluster 3, 5 Hz Spectral Acceleration,Using the Analytical Adjustment for Site Conditions ..................................................... 7-100

Table 7.5.3-32 Calculation of GMPE Weights for Cluster 3, 5 Hz Spectral Acceleration,Using the Empirical Adjustment for Site Conditions ...................................................... 7-100

Table 7.5.3-33 Calculation of GMPE Weights for Cluster 3, 2.5 Hz Spectral Acceleration,Using the Analytical Adjustment for Site Conditions ..................................................... 7-101

Table 7.5.3-34 Calculation of GMPE Weights for Cluster 3, 2.5 Hz Spectral Acceleration,Using the Empirical Adjustment for Site Conditions ...................................................... 7-101

Table 7.5.3-35 Calculation of GMPE Weights for Cluster 3, 1 Hz Spectral Acceleration,Using the Analytical Adjustment for Site Conditions ..................................................... 7-102

Table 7.5.3-36 Calculation of GMPE Weights for Cluster 3, 1 Hz Spectral Acceleration,Using the Empirical Adjustment for Site Conditions ...................................................... 7-102

Table 7.5.3-37 Calculation of GMPE Weights for Cluster 3, 0.5 Hz Spectral Acceleration,Using the Analytical Adjustment for Site Conditions ..................................................... 7-103

Table 7.5.3-38 Calculation of GMPE Weights for Cluster 3, 0.5 Hz Spectral Acceleration,Using the Empirical Adjustment for Site Conditions ...................................................... 7-103

Table 7.5.3-39 Combination of GMPE Weights for Cluster 3 ................................................ 7-104

Table 7.5.3-40 Raw and Moderated Within-Cluster Weights ................................................ 7-104

Table 7.7.1-1 Parameters of Data Constraint Within-Cluster Standard Deviation ................ 7-105

Table 7.7.1-2 Magnitude Scaling Variability Across All GMPEs ........................................... 7-106

Table 7.7.1-3 Magnitude Scaling Variability Across Cluster 1-3 GMPEs ............................. 7-107

Table 7.9-1 Calculation of Data-Consistency Cluster Weights for 25 Hz SpectralAcceleration, Using the Analytical Adjustment for Site Conditions ................................ 7-108

Table 7.9-2 Calculation of Data-Consistency Cluster Weights for 25 Hz SpectralAcceleration, Using the Empirical Adjustment for Site Conditions ................................. 7-108


XXI




Table 7.9-7 Calculation of Data-Consistency Cluster Weights for 2.5 Hz SpectralAcceleration, Using the Analytical Adjustment for Site Conditions ................................ 7-111

Table 7.9-8 Calculation of Data-Consistency Cluster Weights for 2.5 Hz SpectralAcceleration, Using the Empirical Adjustment for Site Conditions ................................. 7-111



Table 7.9-11 Calculation of Data-Consistency Cluster Weights for 0.5 Hz SpectralAcceleration, Using the Analytical adjustment for Site Conditions ................................ 7-113

Table 7.9-12 Calculation of Data-Consistency Cluster Weights for 0.5 Hz SpectralAcceleration, Using the Empirical Adjustment for Site Conditions ................................. 7-113

Table 7.9-13 Combination of Data-Consistency Cluster Weights Across Frequencies andAcross Approaches for Site Adjustment ....................................................................... 7-114

Table 7.9-14 Calculation of Cluster Weights on the Basis of Combined Data-Consistency Weights and Confidence Weights ............................................................. 7-115

Table 7.10.2-1 Aleatory Variability for Active Tectonic Regions Based on the NGAP roje cts ........................................................................................................................ 7 -1 16

Table 7.10.2-2 Update Aleatory Variability CEUS Ground Motions ...................................... 7-117

Table 7.11.1-1 Earthquakes Used for of Analysis of Gulf Coast Region Q ........................... 7-118

Table 7.11.1-2 Estimated Values of Q for Gulf Coast Region ............................................... 7-119

Table 8.1-1 Description of Seven Test Sites ............................................................................ 8-8

Table A-1 List of digital data layers included in the EPRI (2004, 2006) GMM ReviewP roject database .................................................................................................. A -i 1

Table B-1 A tkinson (2004a) ..................................................................................................... B-3

T able B -2 A tkinson (2004b) ..................................................................................................... B -3

T able B-3 C am pbell (2004) ..................................................................................................... B-4

Table B-4 Tavakoli and Pezeshk (2005) .................................................................................. B-4

Table B-5 Atkinson and Boore (2006) ................................................................................ B-5

Table B-6 D ouglas et al. (2006) .............................................................................................. B-6

Table B-7 Sonley and Atkinson (2006) .................................................................................... B-6

Table B-8 Atkinson and Kaka (2007) ....................................................................................... B-7

Table B-9 Atkinson and Wald (2007) ....................................................................................... B-7

Table B-10 Raghu Kanth and lyengar (2007) .......................................................................... B-8

XXll

T able B -1 1 A tkinson (2008) ..................................................................................................... B -8

Table B-1 2 Atkinson and Morrison (2009) ............................................................................... B-9

Table B-13 Cam pbell (2009) ............................................................................................... B-9

Table B-14 Somerville et al. (2009) .................................................................................. B-10

Table B-1 5 Atkinson and Kraeva (2010) ............................................................................ B-i 1

Table B-16 Boore et al. (2010) ......................................................................................... B-11

Table B-17 Zandieh and Pezeshk (2010) .......................................................................... B-12

Table B-1 8 Atkinson and Boore (2011) .............................................................................. B-13

Table B-1 9 Atkinson et al. (2011) ....................................................................................... B-13

Table B-20 Boatwright and Seekins (2011) ........................................................................... B-14

Table B-21 Pezeshk et al. (2011) .......................................................................................... B-14

T able B -22 A tkinson (2012) ................................................................................................... B -15

Table B-23 Boore (2012) .................................................................................................. B-16

Table C-1 Norm Abrahamson - June 21, 2012 ....................................................................... C-3

Table C-2 Gail Atkinson - July 6, 2012 ................................................................................... C-4

Table C-3 Jack Boatwright - October 4, 2012 ......................................................................... C-6

Table C-4 David Boore - June 26, 2012 ................................................................................. C-7

Table C-5 Kenneth Campbell - June 20, 2012 ........................................................................ C-8

Table C-6 Chris Cramer - July 3, 2012 ................................................................................... C-9

Table C-7 Arthur Frankel - July 31, 2012 .......................................................................... C-10

Table C-8 Bob Herrmann - September 11, 2012 ............................................................. C-i 1

Table C-9 Shahram Pezeshk - June 26, 2012 ...................................................................... C-12

Table C-10 Walter Silva - July 17, 2012 ............................................................................... C-14

Table C-11 Paul Somerville - July 9, 2012 ........................................................................ C-16

Table G .2.1-1 C luster W eights ................................................................................................ G -9

Table G.2.3-1 GMPE Coefficients for Cluster 1, Midcontinent Region (2 Sheets) ............. G-10

Table G.2.3-2 GMPE Coefficients for Cluster 2, Midcontinent Region (2 Sheets) ............. G-12

Table G.2.3-3 GMPE Coefficients for Cluster 3, Midcontinent Region (2 Sheets) .................. G-14

Table G.2.3-4 GMPE Coefficients for Cluster 4 Rifted, Midcontinent Region ......................... G-16

Table G.2.3-5 GMPE Coefficients for Cluster 4 Non-rifted, Midcontinent Region ............. G-17

Table G.2.3-6 GMPE Coefficients for Cluster 1, Gulf Region (2 Sheets) .......................... G-18

Table G.2.3-7 GMPE Coefficients for Cluster 2, Gulf Region (2 Sheets) ............................... G-20

Table G.2.3-8 GMPE Coefficients for Cluster 3, Gulf Region (2 Sheets) ............................... G-22

Table G.2.3-9 GMPE Coefficients for Cluster 4 Rifted, Gulf Region ...................................... G-24

Table G.2.3-1 0 GMPE Coefficients for Cluster 4 Non-rifted, Gulf Region .............................. G-25

XXIII

Table G.2.4-1 Cluster 1 Adjustment from Epicentral to Joyner-Boore Distance (centeredru ptu re s ) ................................................................................................................. G -2 6

Table G.2.4-2 Cluster 1 Adjustment from Epicentral to Joyner-Boore Distance (randomru ptu re s) ................................................................................................................. G -2 6

Table G.2.4-3 Cluster 2 Adjustment from Epicentral to Joyner-Boore Distance (centeredru ptu re s ) ................................................................................................................. G -2 7

Table G.2.4-4 Cluster 2 Adjustment from Epicentral to Joyner-Boore Distance (randomru ptu re s ) ................................................................................................................. G -2 7

Table G.2.4-5 Cluster 3 Adjustment from Epicentral to Joyner-Boore Distance (centeredru ptu re s) ................................................................................................................. G -2 8

Table G.2.4-6 Cluster 3 Adjustment from Epicentral to Joyner-Boore Distance (randomru ptu re s ) ................................................................................................................. G -2 8

Table G.2.4-7 New Cluster 4 Adjustment from Epicentral to Joyner-Boore Distance(centered ruptures) .................................................................................................. G -29

Table G.2.4-8 New Cluster 4 Adjustment from Epicentral to Joyner-Boore Distance(random ruptures) ................................................................................................... G -29

Table G.2.4-9 Cluster 1 Adjustment from Epicentral to Joyner-Boore Distance (centeredruptures) - Additional Aleatory Variability ................................................................ G-30

Table G.2.4-10 Cluster 1 Adjustment from Epicentral to Joyner-Boore Distance (randomruptures) - Additional Aleatory Variability ................................................................ G-30

Table G.2.4-11 Cluster 2 Adjustment from Epicentral to Joyner-Boore Distance(centered ruptures) - Additional Aleatory Variability ................................................ G-31






Table G.2.5-1 Aleatory Uncertainty (sigma) in Ground-Motion Amplitude .............................. G-34

Table G.3.4-1 List of Attachments in AppendixGElectronic_AttachmentsMarch.zip ......... G-35

xxiv

LIST OF FIGURES

Figure 1.3-1 Map of project study region showing sub-regions for the Updated EPRI(2004, 2006) Ground-Motion Model and test site locations for seismic hazardca lc u la tio n s ...................................................................................................................... 1-9

Figure 2.2-1 Project flow chart, including decision points ....................................................... 2-14

Figure 3.2-1 EPRI (2004, 2006) GMM Review Project organization chart .............................. 3-14

Figure 3.3-1 Chart showing lines of communication and points of contact .......................... 3-15

Figure 4-1 Locations of seismic recording stations in the Central and Eastern UnitedS ta te s ............................................................................................................................. 4 -1 1

Figure 4.4-1 Locations of USGS Virginia stations ................................................................... 4-12

Figure 5.1.4-1 EPRI (2004) Ground Motion Model regionalization based on EPRI(19 9 3 a ) ............................................................................................................................. 5 -6

Figure 7.2.4-1 Empirical distributions for vertical location of hypocenter in rupture plane, developed by Chiou and Youngs (2008b) ..................................................................... 7-120

Figure 7.2.4-2 Distributions for horizontal location of hypocenter in rupture planedeveloped by Chiou and Youngs (2008b) ..................................................................... 7-121

Figure 7.2.4-3 Comparison of epicentral and simulated Joyner-Boore distances for theground m otion database ............................................................................................... 7-122

Figure 7.2.5-1 Distribution of VS30 values for recording stations in final ground-motiondatabase ....................................................................................................... 7-123

Figure 7.2.5-2 Distribution of Vs30 values for recording stations with geologicalcla ssificatio ns ............................................................................................................... 7-124

Figure 7.2.6-1 (1 of 3) Magnitude-distance distribution of rock site ground-motion data ....... 7-125



Figure 7.2.6-2 Map of earthquakes of magnitude 3.75 _ M < 4.75 in project ground-motion database. Note: the number of earthquakes may appear to be different fromthe number in Table 7.2.6-1 because some epicentral locations may coincide ............. 7-128

Figure 7.2.6-3 Map of earthquakes of magnitude M -> 4.75 in project ground-motiond ata ba se ...................................................................................................................... 7-12 9

Figure 7.2.6-4a Map of recording stations for earthquakes of magnitude 3.75 _ M < 4.75and RJB < 500 km contributing 25 Hz PSA data to project ground-motion database ..... 7-130

Figure 7.2.6-4b Map of recording stations for earthquakes of magnitude 3.75 ! M < 4.75and RJB - 500 km contributing 10 Hz PSA data to project ground-motion database ..... 7-131

Figure 7.2.6-4c Map of recording stations for earthquakes of magnitude 3.75 ! M < 4.75and RJB - 500 km contributing 5 Hz PSA data to project ground-motion database ....... 7-132

Figure 7.2.6-4d Map of recording stations for earthquakes of magnitude 3.75 _ M < 4.75and RJB - 500 km contributing 2.5 Hz PSA data to project ground-motion database .... 7-133

Figure 7.2.6-4e Map of recording stations for earthquakes of magnitude 3.75 - M < 4.75and RJB - 500 km contributing 1 Hz PSA data to project ground-motion database ....... 7-134

Figure 7.2.6-4f Map of recording stations for earthquakes of magnitude 3.75 _ M < 4.75and RJB -< 500 km contributing 0.5 Hz PSA data to project ground-motion database .... 7-135

xxv

Figure 7.2.6-5a Map of recording stations for earthquakes of magnitude M > 4.75 andRJB < 500 km contributing 25 Hz PSA data to project ground-motion database ............ 7-136

Figure 7.2.6-5b Map of recording stations for earthquakes of magnitude M > 4.75 andRJB < 500 km contributing 10 Hz PSA data to project ground-motion database ............ 7-137

Figure 7.2.6-5c Map of recording stations for earthquakes of magnitude M > 4.75 andRJB < 500 km contributing 5 Hz PSA data to project ground-motion database .............. 7-138

Figure 7.2.6-5d Map of recording stations for earthquakes of magnitude M > 4.75 andRJB < 500 km contributing 2.5 Hz PSA data to project ground-motion database ........... 7-139

Figure 7.2.6-5e Map of recording stations for earthquakes of magnitude M > 4.75 andRjB3 - 500 km contributing 1 Hz PSA data to project ground-motion database .............. 7-140

Figure 7.2.6-5f Map of recording stations for earthquakes of magnitude M > 4.75 and RjB< 500 km contributing 0.5 Hz PSA data to project ground-motion database ................. 7-141

Figure 7.3.1.1-1 Template shear-wave-velocity profiles used for extending the measuredprofiles. Source: EPRI (2013). The three profiles not identified in the legendcorrespond to VS30 values of 1,364, 2,032, and 2830 m/s ............................................. 7-142

Figure 7.3.1.1-2 Example of measured shear-wave-velocity profile for station ET.SWETas m easured by the University of Texas ....................................................................... 7-143

Figure 7.3.1.1-3 Example of extended shear-wave-velocity profile for station ET.SWET ...... 7-144

Figure 7.3.1.2-1 Calculation of the [recording site]/[reference site] Fourier amplificationfactor for rock station ET.SW ET ................................................................................... 7-146

Figure 7.3.1.2-2 Calculation of the [recording site]/[reference site] Fourier amplificationfactor for rock station N M .U S IN .................................................................................... 7-147

Figure 7.3.1.2-3 Calculation of the [recording site]/[reference site] Fourier amplificationfactor for rock station C N .O TT ...................................................................................... 7-148

Figure 7.3.1.2-4 Adjusted and original response spectra for an M 4.6 earthquakerecorder at rock station ET.SWET at a distance of 85 km ............................................. 7-149

Figure 7.3.1.2-5 Adjusted and original response spectra for an M 5.3 earthquakerecorder at rock station NM.USIN at a distance of 56 km ............................................. 7-150

Figure 7.3.1.2-6 Adjusted and original response spectra for an M 5.1 earthquakerecorder at rock station CN.OTT at a distance of 55 km ............................................... 7-151

Figure 7.3.2-1 Example residuals for the project ground-motion database computedusing the EPRI (2004) Cluster 1 median GMPE ........................................................... 7-152

Figure 7.3.2-2 Coefficients of Model 1 (Equation 7.3.2-1) and Model 2 (Equation 7.3.2-2)fit to residual for the project ground-motion database using the EPRI (2004) Cluster1 m edian G M P E ........................................................................................................... 7-153

Figure 7.3.3-1 Comparison of analytical and empirical amplification factors for 1 Hz.Results shown are based on data for M > 4.75 and RJB -< 500 km ................................ 7-154

Figure 7.3.3-2 Comparison of analytical and empirical amplification factors for 5 Hz ..... 7-155Figure 7.3.3-3 Comparison of analytical and empirical amplification factors for 10 Hz .......... 7-156

Figure 7.3.3-4 Comparison of analytical and empirical amplification factors for 25 Hz .......... 7-157

Figure 7.3.3-5 NGA amplification factors for magnitude 6 at 100 km. Modified fromA braham son et al. (2008) ............................................................................................. 7-158

Figure 7.4.2-1 Individual earthquake event terms obtained from fitting the residuals forthe A08' G M PE using Equation 7.3.2-3 ........................................................................ 7-159

XXVI

Figure 7.4.2-2 Individual earthquake event terms obtained from fitting the residuals forthe AB06' G M PE using Equation 7.3.2-3 ...................................................................... 7-160

Figure 7.4.2-3 Individual earthquake event terms obtained from fitting the residuals forthe FEL G M PE using Equation 7.3.2-3 ......................................................................... 7-161

Figure 7.4.2-4 Individual earthquake event terms obtained from fitting the residuals forthe PZT GM PE using Equation 7.3.2-3 ......................................................................... 7-162

Figure 7.4.2-5 Individual earthquake event terms obtained from fitting the residuals forthe SDCS GM PE using Equation 7.3.2-3 ...................................................................... 7-163

Figure 7.4.2-6 Individual earthquake event terms obtained from fitting the residuals forthe SSCCSS GM PE using Equation 7.3.2-3 ................................................................. 7-164

Figure 7.4.2-7 Individual earthquake event terms obtained from fitting the residuals forthe SSCVS GM PE using Equation 7.3.2-3 ................................................................... 7-165

Figure 7.4.2-8 Individual earthquake event terms obtained from fitting the residuals forthe SEL G M PE using Equation 7.3.2-3 ......................................................................... 7-166

Figure 7A.2-9 Individual earthquake event terms obtained from fitting the residuals forthe TEL G M PE using Equation 7.3.2-3 ......................................................................... 7-167

Figure 7.4.2-10 Scaling coefficients for Equations 7.4.2-1, 7.4.2-2, and 7.4.2-3 obtainedfrom fitting the residuals for M > 3.75 earthquakes using the nine candidate GMPEs ...7-168

Figure 7.4.2-11 Scaling coefficients for Equations 7.4.2-1, 7.4.2-2, and 7.4.2-3 obtainedfrom fitting the residuals for M > 4.75 earthquakes using the nine candidate GMPEs ... 7-169

Figure 7A4.4.1 Parameterization of the mean ground-motion residual as a function ofdistance for the calculation of the epistemic-uncertainty term Udata constraint ..................... 7-170

Figure 7,5.1-1a Residuals for analytically adjusted spectral accelerations from 3.75 < M< 4.75 earthquakes computed using the SSCCSS GMPE ............................................ 7-171

Figure 7.5.1-1b Residuals for analytically adjusted spectral accelerations from M > 4.75earthquakes computed using the SSCCSS GMPE ....................................................... 7-172

Figure 7,5.1-2a Residuals for analytically adjusted spectral accelerations from 3.75 < M< 4.75 earthquakes computed using the SSCVS GMPE .............................................. 7-173

Figure 7,5.1-2b Residuals for analytically adjusted spectral accelerations from M > 4.75earthquakes computed using the SSCVS GMPE ......................................................... 7-174

Figure 7,5.1-3a Residuals for analytically adjusted spectral accelerations from 3.75 < M< 4.75 earthquakes computed using the TEL GMPE .................................................... 7-175

Figure 7.5.1-3b Residuals for analytically adjusted spectral accelerations from M > 4.75earthquakes computed using the TEL GMPE ............................................................... 7-176

Figure 7,5.1-4a Residuals for analytically adjusted spectral accelerations from 3.75 < M< 4.75 earthquakes computed using the FEL GMPE .................................................... 7-177

Figure 7,5.1-4b Residuals for analytically adjusted spectral accelerations from M > 4.75earthquakes computed using the FEL GMPE ............................................................... 7-178

Figure 7.5.1-5a Residuals for analytically adjusted spectral accelerations from 3.75 < M< 4.75 earthquakes computed using the A08' GMPE .................................................... 7-179

Figure 7.5.1-5b Residuals for analytically adjusted spectral accelerations from M > 4.75earthquakes computed using the A08' GMPE .............................................................. 7-180

Figure 7.5.1-6a Residuals for analytically adjusted spectral accelerations from 3.75 < M< 4.75 earthquakes computed using the SDCS GMPE ................................................. 7-181

XXVll

Figure 7.5.1-6b Residuals for analytically adjusted spectral accelerations from M > 4.75earthquakes computed using the SDCS GMPE ............................................................ 7-182

Figure 7.5.1-7a Residuals for analytically adjusted spectral accelerations from 3.75 < M< 4.75 earthquakes computed using the AB06' GMPE ................................................. 7-183

Figure 7.5.1-7b Residuals for analytically adjusted spectral accelerations from M > 4.75earthquakes computed using the AB06' GMPE ............................................................ 7-184

Figure 7.5.1-8a Residuals for analytically adjusted spectral accelerations from 3.75 < M< 4.75 earthquakes computed using the PZT GMPE .................................................... 7-185

Figure 7.5.1-8b Residuals for analytically adjusted spectral accelerations from M > 4.75earthquakes computed using the PZT GMPE ............................................................... 7-186

Figure 7.5.1-9a Residuals for analytically adjusted spectral accelerations from 3.75 < M< 4.75 earthquakes computed using the SEL GMPE .................................................... 7-187

Figure 7.5.1-9b Residuals for analytically adjusted spectral accelerations from M > 4.75earthquakes computed using the SEL GMPE ............................................................... 7-188

Figure 7.5.2-1a Residuals for empirically adjusted empirically adjusted spectralaccelerations from magnitude 3.75 < M < 4.75 earthquakes computed using theS S C C S S G M P E ........................................................................................................... 7-189

Figure 7.5.2-1b Residuals for empirically adjusted spectral accelerations from magnitudeM > 4.75 earthquakes computed using the SSCCSS GMPE ........................................ 7-190

Figure 7.5.2-2a Residuals for empirically adjusted spectral accelerations from magnitude3.75•< M < 4.75 earthquakes computed using the SSCVS GMPE ................................ 7-191

Figure 7.5.2-2b Residuals for empirically adjusted spectral accelerations from magnitudeM > 4.75 earthquakes computed using the SSCVS GMPE ........................................... 7-192

Figure 7.5.2-3a Residuals for empirically adjusted spectral accelerations from magnitude3.75 < M < 4.75 earthquakes computed using the TEL GMPE ..................................... 7-193

Figure 7.5.2-3b Residuals for empirically adjusted spectral accelerations from magnitudeM > 4.75 earthquakes computed using the TEL GMPE ................................................ 7-194

Figure 7.5.2-4a Residuals for empirically adjusted spectral accelerations from magnitude3.75 < M < 4.75 earthquakes computed using the FEL GMPE ..................................... 7-195

Figure 7.5.2-4b Residuals for empirically adjusted spectral accelerations from magnitudeM > 4.75 earthquakes computed using the FEL GMPE ................................................ 7-196

Figure 7.5.2-5a Residuals for empirically adjusted spectral accelerations from magnitude3.75 < M < 4.75 earthquakes computed using the A08' GMPE ..................................... 7-197

Figure 7.5.2-5b Residuals for empirically adjusted spectral accelerations from magnitudeM > 4.75 earthquakes computed using the A08' GMPE ................................................ 7-198

Figure 7.5.2-6a Residuals for empirically adjusted spectral accelerations from magnitude3.75 5 M < 4.75 earthquakes computed using the SDCS GMPE .................................. 7-199

Figure 7.5.2-6b Residuals for empirically adjusted spectral accelerations from magnitudeM > 4.75 earthquakes computed using the SDCS GMPE ............................................. 7-200

Figure 7.5.2-7a Residuals for empirically adjusted spectral accelerations from magnitude3.75 < M < 4.75 earthquakes computed using the AB06' GMPE .................................. 7-201

Figure 7.5.2-7b Residuals for empirically adjusted spectral accelerations from magnitudeM > 4.75 earthquakes computed using the ABO6' GMPE ............................................. 7-202

XXVIIi

Figure 7.5.2-8a Residuals for empirically adjusted spectral accelerations from magnitude3.75 < M < 4.75 earthquakes computed using the PZT GMPE ..................................... 7-203

Figure 7.5.2-8b Residuals for empirically adjusted spectral accelerations from magnitudeM > 4.75 earthquakes computed using the PZT GMPE ................................................ 7-204

Figure 7.5.2-9a Residuals for empirically adjusted spectral accelerations from magnitude3.75 < M < 4.75 earthquakes computed using the SEL GMPE ..................................... 7-205

Figure 7.5.2-9b Residuals for empirically adjusted spectral accelerations from magnitudeM > 4.75 earthquakes computed using the SEL GMPE ................................................ 7-206

Figure 7.5.2-10a Soft-rock -scaling coefficient CSR obtained from fitting the residuals forSSCCSS (top), SSCVS (middle), and TEL (bottom) ..................................................... 7-207

Figure 7.5.2-10b Soft-rock-scaling coefficient CSR obtained from fitting the residuals forFEL (top), A08' (middle), and SDCS (bottom) ............................................................... 7-208

Figure 7.5.2-10c Soft-rock-scaling coefficient CSR obtained from fitting the residuals forAB06' (top), PZT (m iddle), and SEL (bottom ) ............................................................... 7-209

Figure 7.6.1-1 Depth distributions for well-located earthquakes in the NUREG-2115earthquake catalog ....................................................................................................... 7-2 10

Figure 7.6.2-1a Development of median PGA motions for Cluster 1 .................................... 7-211Figure 7.6.2-1b Development of median 25 Hz PSA motions for Cluster 1 ........................... 7-212

Figure 7.6.2-1c Development of median 10 Hz PSA motions for Cluster 1 ........................... 7-213Figure 7.6.2-1d Development of median 5 Hz PSA motions for Cluster 1 ............................. 7-214

Figure 7.6.2-le Development of median 2.5 Hz PSA motions for Cluster 1 .......................... 7-215

Figure 7.6.2-1f Development of median 1 Hz PSA motions for Cluster 1 .............................. 7-216Figure 7.6.2-1g Development of median 0.5 Hz PGA motions for Cluster 1 ......................... 7-217Figure 7.6.2-2a Development of median PGA motions for Cluster 2 .................................... 7-218

Figure 7.6.2-2b Development of median 25 Hz PSA motions for Cluster 2 ........................... 7-219Figure 7.6.2-2c Development of median 10 Hz PSA motions for Cluster 2 ........................... 7-220

Figure 7.6.2-2d Development of median 5 Hz PSA motions for Cluster 2 ............................. 7-221

Figure 7.6.2-2e Development of median 2.5 Hz PSA motions for Cluster 2 .......................... 7-222

Figure 7.6.2-2f Development of median 1 Hz PSA motions for Cluster 2 .............................. 7-223Figure 7.6.2-2g Development of median 0.5 Hz PGA motions for Cluster 2 ......................... 7-224

Figure 7.6.2-3a Development of median PGA motions for Cluster 3 .................................... 7-225Figure 7.6.2-3b Development of median 25 Hz PSA motions for Cluster 3 ........................... 7-226

Figure 7.6.2-3c Development of median 10 Hz PSA motions for Cluster 3 ........................... 7-227Figure 7.6.2-3d Development of median 5 Hz PSA motions for Cluster 3 ............................. 7-228

Figure 7.6.2-3e Development of median 2.5 Hz PSA motions for Cluster 3 .......................... 7-229

Figure 7.6.2-3f Development of median 1 Hz PSA motions for Cluster 3 .............................. 7-230

Figure 7.6.2-3g Development of median 0.5 Hz PGA motions for Cluster 3 ......................... 7-231Figure 7.6.2-4 Fit of Equation 7.6.2-1 to Cluster 1 median ground motions .......................... 7-232

Figure 7.6.2-5 Fit of Equation 7.6.2-2 to Cluster 2 median ground motions .......................... 7-233

Figure 7.6.2-6 Fit of Equation 7.6.2-1 to Cluster 3 median ground motions .......................... 7-234

Figure 7.7.1-1 Model-to-model variability for Cluster 1 ......................................................... 7-235

XXIX



Figure 7.7.1-4a Magnitude scaling of PGA for nine candidate GMPEs ................................. 7-238

Figure 7.7.1-4b Magnitude scaling of 25 Hz PSA for nine candidate GMPEs ....................... 7-239

Figure 7.7.1-4c Magnitude scaling of 10 Hz PSA for nine candidate GMPEs ....................... 7-240

Figure 7.7.1-4d Magnitude scaling of 5 Hz PSA for nine candidate GMPEs ......................... 7-241

Figure 7.7.1-4e Magnitude scaling of 2.5 Hz PSA for nine candidate GMPEs ...................... 7-242

Figure 7.7.1-4f Magnitude scaling of 1 Hz PSA for nine candidate GMPEs .......................... 7-243

Figure 7.7.1-4g Magnitude scaling of 0.5 Hz PSA for nine candidate GMPEs ...................... 7-244

Figure 7.7.1-5 Values of total a'(fsF)(M) computed from the MSF(M) values for the

nine candidate G M P Es ................................................................................................. 7-245

Figure 7.7.1-6 Values of cluster-to-cluster o-,4IsFr)(M) computed from the MSF(M)

values for the four cluster median GMPEs .................................................................... 7-246

Figure 7.7.1-7 Values of total O',(AF) (M) computed from the MSF(M) values for the

eight candidate GMPEs in Clusters 1, 2, and 3 ............................................................. 7-247

Figure 7.7.1-8 Values of cluster-to-cluster a-,•( F)(M) computed from the MSF(M)

values for the Cluster 1, 2, and 3 median GMPEs ........................................................ 7-248

Figure 7.7.1-9 Cluster-independent values of within-cluster epistemic standard deviation ...7-249

Figure 7.7.1-10 Within-cluster epistemic standard deviation of the median groundm otions for C luster 1 .................................................................................................... 7-250

Figure 7.7.1-11 Within-cluster epistemic standard deviation of the median groundm otions for C luster 2 .................................................................................................... 7-25 1



Figure 7.7.2-1a Cluster 1 5th percentile GMPEs .................................................................. 7-254

Figure 7.7.2-1b Cluster 1 95th percentile GMPEs ................................................................ 7-255





Figure 7.7.2-4a Cluster 4 5th percentile GMPEs for rift earthquakes .................................... 7-260

Figure 7.7.2-4b Cluster 4 95th percentile GMPEs for rift earthquakes .................................. 7-261

Figure 7.7.2-5a Cluster 1 5th percentile GMPEs for non-rift earthquakes ............................. 7-262

Figure 7.7.2-5b Cluster 1 95th percentile GMPEs for non-rift earthquakes ........................... 7-263

Figure 7.8.1-1a Distance adjustments for Cluster 1, PGA .................................................... 7-264

Figure 7.8.1-1b Distance adjustments for Cluster 1, 25 Hz PSA .......................................... 7-265

Figure 7.8.1-1c Distance adjustments for Cluster 1, 10 Hz PSA ........................................... 7-266

XXX

Figure 7.8.1-1d Distance adjustments for Cluster 1, 5 Hz PSA ............................................ 7-267

Figure 7.8.1-1e Distance adjustments for Cluster 1, 2.5 Hz PSA ......................................... 7-268

Figure 7.8.1-1f Distance adjustments for Cluster 1, 1 Hz PSA ............................................. 7-269

Figure 7.8.1-1g Distance adjustments for Cluster 1, 0.5 Hz PSA ......................................... 7-270





Figure 7.8.1-2e Distance adjustments for Cluster 2, 2.5 Hz PSA .......................................... 7-275








Figure 7.8.1-3f Distance adjustments for Cluster 3, 1 Hz PSA ............................................. 7-283Figure 7.8.1-3g Distance adjustments for Cluster 3, 0.5 Hz PSA ......................................... 7-284


Figure 7.8.1-4b Distance adjustments for Cluster 4, 25 Hz PSA .......................................... 7-286Figure 7.8.1-4c Distance adjustments for Cluster 4, 10 Hz PSA ........................................... 7-287





Figure 7.8.2-1a Added aleatory sigma for Cluster 1, PGA .................................................... 7-292

Figure 7.8.2-1b Added aleatory sigma for Cluster 1, 25 Hz PSA .......................................... 7-293

Figure 7.8.2-1c Added aleatory sigma for Cluster 1, 10 Hz PSA .......................................... 7-294Figure 7.8.2-1d Added aleatory sigma for Cluster 1, 5 Hz PSA ............................................ 7-295

Figure 7.8.2-1e Added aleatory sigma for Cluster 1, 2.5 Hz PSA ......................................... 7-296Figure 7.8.2-1f Added aleatory sigma for Cluster 1, 1 Hz PSA ............................................. 7-297

Figure 7.8.2-1g Added aleatory sigma for Cluster 1, 0.5 Hz PSA ......................................... 7-298



Figure 7.8.2-2c Added aleatory sigma for Cluster 2, 10 Hz PSA .......................................... 7-301

Figure 7.8.2-2d Added aleatory sigma for Cluster 2, 5 Hz PSA ............................................ 7-302

Figure 7.8.2-2e Added aleatory sigma for Cluster 2, 2.5 Hz PSA ......................................... 7-303Figure 7.8.2-2f Added aleatory sigma for Cluster 2, 1 Hz PSA ............................................. 7-304


XXXI

Figure 7.8.2-3a Added aleatory sigma for Cluster 3, PGA .................................................... 7-306Figure 7.8.2-3b Added aleatory sigma for Cluster 3, 25 Hz PSA .......................................... 7-307

Figure 7.8.2-3c Added aleatory sigma for Cluster 3, 10 Hz PSA ......................................... 7-308

Figure 7.8.2-3d Added aleatory sigma for Cluster 3, 5 Hz PSA ............................................ 7-309

Figure 7.8.2-3e Added aleatory sigma for Cluster 3, 2.5 Hz PSA ......................................... 7-310

Figure 7.8.2-3f Added aleatory sigma for Cluster 3, 1 Hz PSA ............................................. 7-311




Figure 7.8.2-4c Added aleatory sigma for Cluster 4, 10 Hz PSA .......................................... 7-315

Figure 7.8.2-4d Added aleatory sigma for Cluster 4, 5 Hz PSA ............................................ 7-316Figure 7.8.2-4e Added aleatory sigma for Cluster 4, 2.5 Hz PSA ......................................... 7-317

Figure 7.8.2-4f Added aleatory sigma for Cluster 4, 1 Hz PSA ............................................. 7-318


Figure 7.9.1-1a Residuals for analytically adjusted spectral accelerations frommagnitude 3.75 < M < 4.75 earthquakes computed using the Cluster 1 medianG M P E .......................................................................................................................... 7 -3 2 0

Figure 7.9.1-1b Residuals for analytically adjusted spectral accelerations frommagnitude M > 4.75 earthquakes computed using the Cluster 1 median GMPE ........... 7-321







Figure 7.9.2-1a Residuals for empirically adjusted spectral accelerations from magnitude3.75 < M < 4.75 earthquakes computed using the Cluster 1 median GMPE ................. 7-328

Figure 7.9.2-1 b Residuals for empirically adjusted spectral accelerations from magnitudeM > 4.75 earthquakes computed using the Cluster 1 median GMPE ............................ 7-329


Figure 7.9.2-2b Residuals for empirically adjusted spectral accelerations from magnitudeM > 4.75 earthquakes computed using the Cluster 2 median GMPE ............. 7-331

XXXII


Figure 7.9.2-3b Residuals for empirically adjusted spectral accelerations from magnitudeM > 4.75 earthquakes computed using the Cluster 3 median GMPE ............................ 7-333


Figure 7.9.2-4b Residuals for empirically adjusted spectral accelerations from magnitudeM > 4.75 earthquakes computed using the Cluster 4 median GMPE ............................ 7-335

Figure 7.9.2-5a Soft-rock-scaling coefficient CSR obtained from fitting the residuals forCluster 1 (top) and Cluster 2 (bottom ) .......................................................................... 7-336

Figure 7.9.2-5b Soft-rock-scaling coefficient CSR obtained from fitting the residuals forCluster 3 (top) and Cluster 4 (bottom ) .......................................................................... 7-337

Figure 7.10.2-1 Results of sensitivity tests for the effect of including alternative values ofto ta l a ........................................................................................................................... 7 -3 3 8

Figure 7.10.2-2 Comparison of total u for the EPRI (2006) model and the updatedaleatory variability m odel .............................................................................................. 7-339

Figure 7.11.1-1 Geologic map of the southern U.S. showing the locations of EarthscopeTransportable Array stations, and permanent broadband stations during 2011.Source: G arrity and Soller (2009) ................................................................................. 7-340

Figure 7.11.1-2 Epicenters of earthquakes providing data from analysis (Table 7.11-1).The thick solid line shows the boundary of the Gulf coastal region defined on thebasis of extended crust (EPRI, 2012) ........................................................................... 7-341

Figure 7.11.1-3 Lg travel time versus epicentral distance observed from the February 28,2011, Arkansas earthquake. The line shows a least-squares fit to the data .................. 7-342

Figure 7.11.1-4 Lg duration versus epicentral distance observed from the February 28,2011, Arkansas earthquake. The line shows a least-squares fit to the data .................. 7-343

Figure 7.11.1-5 Horizontal component acceleration recordings at Station P37A innorthern Missouri and Station 441A in southern Louisiana, from the February 28,2011, earthquake in central Arkansas. The epicenter distance is approximately 500km for both stations ...................................................................................................... 7-344

Figure 7.11.1-6 Filled circles show the mean estimates of Q at 12 frequencies between0.25 Hz and 11.2 Hz using data recorded at stations in the Gulf Coast region andassuming Geometric Spreading Model 1. Open circles show estimates of Qassuming a stress drop of 5 MPa; filled circles assume a stress drop of 10 MPa ......... 7-345

Figure 7.11.1-7 The solid line shows mean site response for stations in the Gulf Coastregion south of latitude 33N, using Geometric Spreading Model 1. The dashed anddotted lines show the mean ± standard error estimates of the site terms ...................... 7-346

Figure 7.11.1-8 The solid line shows mean receiver (site) terms for stations in the GulfCoast region south of latitude 33N, using Geometric Spreading Model 1. The dottedline shows a linear regression fit to the site terms, implying a K0 value of 0.096 ±0 .0 10 seco nds .............................................................................................................. 7-34 7

Figure 7.11.1-9 The solid line shows mean site response for stations in the Gulf Coastregion south of latitude 33N, using Geometric Spreading Model 2. The dashed anddotted lines show the mean ± standard error estimates of the site terms ...................... 7-348

XXXIII

Figure 7.11.1-10 The solid line shows mean receiver (site) terms for stations in the GulfCoast region south of latitude 33N, using Geometric Spreading Model 2. The dottedline shows a linear regression fit to the site terms, implying a K0 value of 0.096 ±0 .0 10 se co nds .............................................................................................................. 7-34 9

Figure 7.11.1-11 Residuals (left) and receiver terms (site terms) for 0.25 Hz (top), 0.35Hz (middle) and 0.5 Hz (bottom). Regression assuming Geometric SpreadingM o d e l 1 ........................................................................................................................ 7 -3 5 0

Figure 7.11.1-12 Residuals (left) and receiver terms (site terms) for 0.7 Hz (top), 1.0 Hz(middle) and 1.4 Hz (bottom). Regression assuming Geometric Spreading Model 1 .... 7-351

Figure 7.11.1-13 Residuals (left) and receiver terms (site terms) for 2.0 Hz (top), 2.8 Hz(middle), and 4.0 Hz (bottom). Regression assuming Geometric Spreading Model 1 ...7-352

Figure 7.11.1-14 Residuals (left) and receiver terms (site terms) for 5.6 Hz (top), 8.0 Hz(middle), and 11.2 Hz (bottom). Regression assuming Geometric Spreading Model1 ................................................................................................................................... 7 -3 5 3

Figure 7.11.1-15 Map defining Gulf Coast crustal region ...................................................... 7-354

Figure 7.11.2-1 Comparison of Q models for the Midcontinent and Gulf Coast crustalre g io n s ......................................................................................................................... 7 -3 5 5

Figure 7.11.2-2 Comparison of Midcontinent and Gulf GMPEs for Cluster 1 and 100 Hzspectral acceleration (PGA) .......................................................................................... 7-356

Figure 7.11.2-3 Comparison of Midcontinent and Gulf GMPEs for Cluster 1 and 25 Hzspectral acceleratio n .................................................................................................... 7-357

Figure 7.11.2-4 Comparison of Midcontinent and Gulf GMPEs for Cluster 1 and 10 Hzspectral acceleration ................................................................................................... 7-358

Figure 7.11.2-5 Comparison of Midcontinent and Gulf GMPEs for Cluster 1 and 5 Hzspectral acceleration .................................................................................................... 7-359

Figure 7.11.2-6 Comparison of Midcontinent and Gulf GMPEs for Cluster 1 and 2.5 Hzspectral acceleration .................................................................................................... 7-360

Figure 7.11.2-7 Comparison of Midcontinent and Gulf GMPEs for Cluster 1 and 1 Hzspectral acceleratio n .................................................................................................... 7-36 1


Figure 7.11.2-9 Comparison of Midcontinent and Gulf GMPEs for Cluster 2 and 100 Hzspectral acceleration (PGA) ......................................................................................... 7-363


Figure 7.11.2-11 Comparison of Midcontinent and Gulf GMPEs for Cluster 2 and 10 Hzspectral acceleratio n ................................................................................................... 7-365




XXXIV


Figure 7.11.2-16 Comparison of Midcontinent and Gulf GMPEs for Cluster 3 and 100 Hzspectral acceleration (PGA) .......................................................................................... 7-370

Figure 7.11.2-17 Comparison of Midcontinent and Gulf GMPEs for Cluster 3 and 25 Hzspectral acceleratio n .................................................................................................... 7-37 1



Figure 7.11.2-20 Comparison of Midcontinent and Gulf GMPEs for Cluster 3 and 2.5 Hzspectral acceleratio n .................................................................................................... 7-374



Figure 7.11.2-23 Comparison of Midcontinent and Gulf GMPEs for Cluster 4 (nonriftedsources) and 100 Hz spectral acceleration (PGA) ........................................................ 7-377

Figure 7.11.2-24 Comparison of Midcontinent and Gulf GMPEs for Cluster 4 (nonriftedsources) and 25 Hz spectral acceleration ..................................................................... 7-378

Figure 7.11.2-25 Comparison of Midcontinent and Gulf GMPEs for Cluster 4 (nonriftedsources) and 10 Hz spectral acceleration ..................................................................... 7-379

Figure 7.11.2-26 Comparison of Midcontinent and Gulf GMPEs for Cluster 4 (nonriftedsources) and 5 Hz spectral acceleration ....................................................................... 7-380

Figure 7.11.2-27 Comparison of Midcontinent and Gulf GMPEs for Cluster 4 (nonriftedsources) and 2.5 Hz spectral acceleration .................................................................... 7-381

Figure 7.11.2-28 Comparison of Midcontinent and Gulf GMPEs for Cluster 4 (nonriftedsources) and 1 Hz spectral acceleration ....................................................................... 7-382

Figure 7.11.2-29 Comparison of Midcontinent and Gulf GMPEs for Cluster 4 (nonriftedsources) and 0.5 Hz spectral acceleration .................................................................... 7-383

Figure 7.11.2-30 Comparison of Midcontinent and Gulf GMPEs for Cluster 4 (riftedsources) and 100 Hz spectral acceleration (PGA) ........................................................ 7-384

Figure 7.11.2-31 Comparison of Midcontinent and Gulf GMPEs for Cluster 4 (riftedsources) and 25 Hz spectral acceleration ..................................................................... 7-385

Figure 7.11.2-32 Comparison of Midcontinent and Gulf GMPEs for Cluster 4 (riftedsources) and 10 Hz spectral acceleration ..................................................................... 7-386

Figure 7.11.2-33 Comparison of Midcontinent and Gulf GMPEs for Cluster 4 (riftedsources) and 5 Hz spectral acceleration ....................................................................... 7-387

Figure 7.11.2-34 Comparison of Midcontinent and Gulf GMPEs for Cluster 4 (riftedsources) and 2.5 Hz spectral acceleration .................................................................... 7-388

Figure 7.11.2-35 Comparison of Midcontinent and Gulf GMPEs for Cluster 4 (riftedsources) and 1 Hz spectral acceleration ....................................................................... 7-389

Figure 7.11.2-36 Comparison of Midcontinent and Gulf GMPEs for Cluster 4 (riftedsources) and 0.5 Hz spectral acceleration .................................................................... 7-390

xxxv

Figure 7.12.1-1 Comparison of updated GMM to EPRI (2004) for PGA as a function ofdistance for multiple magnitudes. Figure shows all curves for all clusters in eachmodel and uses line thickness to indicate curve weight ................................................ 7-391

Figure 7.12.1-2 Comparison of updated GMM to EPRI (2004) for spectral acceleration at25 Hz as a function of distance for multiple magnitudes. Figure shows all curves forall clusters in each model and uses line thickness to indicate curve weight .................. 7-392



Figure 7.12.1-5 Comparison of updated GMM to EPRI (2004) for spectral acceleration at2.5 Hz as a function of distance for multiple magnitudes. Figure shows all curves forall clusters in each model and uses line thickness to indicate curve weight .................. 7-395


Figure 7.12.1-7 Comparison of updated GMM to EPRI (2004) for spectral acceleration at0.5 Hz as a function of distance for multiple magnitudes. Figure shows all curves forall clusters in each model and uses line thickness to indicate curve weight .................. 7-397

Figure 7.12.1-8 Comparison of updated GMM to EPRI (2004) for PGA as a function ofdistance for multiple magnitudes. Figure shows arithmetic-mean and percentilecurves for both G M M s .................................................................................................. 7-398

Figure 7.12.1-9 Comparison of updated GMM to EPRI (2004) for spectral acceleration at25 Hz as a function of distance for multiple magnitudes. Figure shows arithmetic-mean and percentile curves for both GMMs ................................................................. 7-399

Figure 7.12.1-10 Comparison of updated GMM to EPRI (2004) for spectral accelerationat 10 Hz as a function of distance for multiple magnitudes. Figure shows arithmetic-mean and percentile curves for both GMMs ................................................................. 7-400

Figure 7.12.1-11 Comparison of updated GMM to EPRI (2004) for spectral accelerationat 5 Hz as a function of distance for multiple magnitudes. Figure shows arithmetic-mean and percentile curves for both GM Ms ................................................................. 7-401

Figure 7.12.1-12 Comparison of updated GMM to EPRI (2004) for spectral accelerationat 2.5 Hz as a function of distance for multiple magnitudes. Figure showsarithmetic-mean and percentile curves for both GMMs ................................................. 7-402

Figure 7.12.1-13 Comparison of updated GMM to EPRI (2004) for spectral accelerationat 1 Hz as a function of distance for multiple magnitudes. Figure shows arithmetic-mean and percentile curves for both GMMs ................................................................. 7-403

Figure 7.12.1-14 Comparison of updated GMM to EPRI (2004) for spectral accelerationat 0.5 Hz as a function of distance for multiple magnitudes. Figure showsarithmetic-mean and percentile curves for both GMMs ................................................. 7-404

Figure 7.12.1-15 Comparison of updated GMM to EPRI (2004) for PGA as a function ofmagnitude for multiple distances. Figure shows arithmetic-mean and percentilecurves for both G M M s .................................................................................................. 7-405

XXXVI

Figure 7.12.1-16 Comparison of updated GMM to EPRI (2004) for spectral accelerationat 25 Hz as a function of magnitude for multiple distances. Figure shows arithmetic-mean and percentile curves for both GMMs ................................................................. 7-406



Figure 7.12.1-19 Comparison of updated GMM to EPRI (2004) for spectral accelerationat 2.5 Hz as a function of magnitude for multiple distances. Figure showsarithmetic-mean and percentile curves for both GMMs .................................................. 7-409


Figure 7.12.1-21 Comparison of updated GMM to EPRI (2004) for spectral accelerationat 0.5 Hz as a function of magnitude for multiple distances. Figure showsarithmetic-mean and percentile curves for both GMMs ................................................. 7-411

Figure 7.12.1-22 Comparison of updated GMM to EPRI (2004) in the form of spectra formultiple magnitudes at a distance (RjB) of 10 km. Figure shows arithmetic-meanand percentile curves for both G M M s ........................................................................... 7-412

Figure 7.12.1-23 Comparison of updated GMM to EPRI (2004) in the form of spectra formultiple magnitudes at a distance (RJB) of 20 km. Figure shows arithmetic-meanand percentile curves for both G M M s ............................................................................ 7-413

Figure 7.12.1-24 Comparison of updated GMM to EPRI (2004) in the form of spectra formultiple magnitudes at a distance (RJB) of 50 km. Figure shows arithmetic-meanand percentile curves for both G M M s ........................................................................... 7-414




Figure 7.12.2-1 Comparison of mean and range of PGA values predicted for hard rocksite by the Atkinson et al. (2012) GMMs with those based on the GMM developed inth is stud y ...................................................................................................................... 7 -4 18

Figure 7.12.2-2 Comparison of mean and range of 10 Hz PSA values predicted for hardrock site by the Atkinson et al. (2012) GMMs with those based on the GMMdeveloped in this study ................................................................................................. 7-4 19

Figure 7.12.2-3 Comparison of mean and range of 5 Hz PSA values predicted for hardrock site by the Atkinson et al. (2012) GMMs with those based on the GMMdeveloped in this study ................................................................................................. 7-420

XXXVII

Figure 7.12.2-4 Comparison of mean and range of 1 Hz PSA values predicted for hardrock site by the Atkinson et al. (2012) GMMs with those based on the GMMdeveloped in this study ................................................................................................. 7-42 1

Figure 7.12.2-5 Comparison of mean and range of 0.5 Hz PSA values predicted for hardrock site by the Atkinson et al. (2012) GMMs with those based on the GMMdeveloped in this study ................................................................................................. 7-422

Figure 7.12.2-6 Comparison of the total aleatory variability model developed by Atkinsonet al. (2012) with the model developed in this study ..................................................... 7-423

Figure 7.12.3-1 Comparison of mean ground motions produced by the updated EPRIGMM with average motions produced by the 2008 NGA GMPEs ................................. 7-424

Figure 8.1-1 Project study region showing sub-regions for the Updated EPRI (2004,2006) Ground-Motion Model and 7 test site locations for seismic hazardca lcu la tio ns ...................................................................................................................... 8 -9

Figure 8.2-1 a Central Illinois site, contribution to rock PGA hazard by seismic source ........... 8-10

Figure 8.2-1b Central Illinois site, contribution to rock 25 Hz hazard by seismic source ......... 8-11

Figure 8.2-1c Central Illinois site, contribution to rock 10 Hz hazard by seismic source ......... 8-12

Figure 8.2-1d Central Illinois site, contribution to rock 5 Hz hazard by seismic source ........... 8-13

Figure 8.2-1e Central Illinois site, contribution to rock 2.5 Hz hazard by seismic source ........ 8-14

Figure 8.2-1f Central Illinois site, contribution to rock 1 Hz hazard by seismic source ............ 8-15

Figure 8.2-1g Central Illinois site, contribution to rock 0.5 Hz hazard by seismic source ........ 8-16

Figure 8.2-1h Central Illinois site, 10-4 and 10-5 rock UHRS ................................................... 8-17

Figure 8.2-2a Chattanooga site, contribution to rock PGA hazard by seismic source ............. 8-18

Figure 8.2-2b Chattanooga site, contribution to rock 25 Hz hazard by seismic source ........... 8-19

Figure 8.2-2c Chattanooga site, contribution to rock 10 Hz hazard by seismic source ........... 8-20

Figure 8.2-2d Chattanooga site, contribution to rock 5 Hz hazard by seismic source ............. 8-21

Figure 8.2-2e Chattanooga site, contribution to rock 2.5 Hz hazard by seismic source ......... 8-22

Figure 8.2-2f Chattanooga site, contribution to rock 1 Hz hazard by seismic source .............. 8-23

Figure 8.2-2g Chattanooga site, contribution to rock 0.5 Hz hazard by seismic source .......... 8-24

Figure 8.2-2h Chattanooga site, 10-4 and 10-5 rock UHRS ..................................................... 8-25

Figure 8.2-3a Houston site, contribution to rock PGA hazard by seismic source .................... 8-26

Figure 8.2-3b Houston site, contribution to rock 25 Hz hazard by seismic source .................. 8-27

Figure 8.2-3c Houston site, contribution to rock 10 Hz hazard by seismic source .................. 8-28

Figure 8.2-3d Houston site, contribution to rock 5 Hz hazard by seismic source .................... 8-29

Figure 8.2-3e Houston site, contribution to rock 2.5 Hz hazard by seismic source ................. 8-30

Figure 8.2-3f Houston site, contribution to rock 1 Hz hazard by seismic source ..................... 8-31

Figure 8.2-3g Houston site, contribution to rock 0.5 Hz hazard by seismic source ................. 8-32

Figure 8.2-3h Houston site, 10-4 and 10-5 rock UHRS ............................................................ 8-33

Figure 8.2-4a Jackson site, contribution to rock PGA hazard by seismic source .................... 8-34

Figure 8.2-4b Jackson site, contribution to rock 25 Hz hazard by seismic source .................. 8-35

Figure 8.2-4c Jackson site, contribution to rock 10 Hz hazard by seismic source ................... 8-36

Figure 8.2-4d Jackson site, contribution to rock 5 Hz hazard by seismic source .................... 8-37

XXXVIII

Figure 8.2-4e Jackson site, contribution to rock 2.5 Hz hazard by seismic source ................. 8-38

Figure 8.2-4f Jackson site, contribution to rock 1 Hz hazard by seismic source ..................... 8-39

Figure 8.2-4g Jackson site, contribution to rock 0.5 Hz hazard by seismic source ................. 8-40

Figure 8.2-4h Jackson site, 10-4 and 10-5 rock UHRS ............................................................ 8-41

Figure 8.2-5a Manchester site, contribution to rock PGA hazard by seismic source ............... 8-42

Figure 8.2-5b Manchester site, contribution to rock 25 Hz hazard by seismic source ............. 8-43

Figure 8.2-5c Manchester site, contribution to rock 10 Hz hazard by seismic source ............. 8-44

Figure 8.2-5d Manchester site, contribution to rock 5 Hz hazard by seismic source ............... 8-45

Figure 8.2-5e Manchester site, contribution to rock 2.5 Hz hazard by seismic source ............ 8-46

Figure 8.2-5f Manchester site, contribution to rock 1 Hz hazard by seismic source ................ 8-47

Figure 8.2-5g Manchester site, contribution to rock 0.5 Hz hazard by seismic source ............ 8-48

Figure 8.2-5h Manchester site, 104 and 10-5 rock UHRS ...................................................... 8-49

Figure 8.2-6a Savannah site, contribution to rock PGA hazard by seismic source ................. 8-50

Figure 8.2-6b Savannah site, contribution to rock 25 Hz hazard by seismic source ............... 8-51

Figure 8.2-6c Savannah site, contribution to rock 10 Hz hazard by seismic source ................ 8-52

Figure 8.2-6d Savannah site, contribution to rock 5 Hz hazard by seismic source ................. 8-53

Figure 8.2-6e Savannah site, contribution to rock 2.5 Hz hazard by seismic source .............. 8-54

Figure 8.2-6f Savannah site, contribution to rock 1 Hz hazard by seismic source .................. 8-55

Figure 8.2-6g Savannah site, contribution to rock 0.5 Hz hazard by seismic source .............. 8-56

Figure 8.2-6h Savannah site, 10-4 and 10-5 rock UHRS .......... : .............................................. 8-57

Figure 8.2-7a Topeka site, contribution to rock PGA hazard by seismic source ..................... 8-58

Figure 8.2-7b Topeka site, contribution to rock 25 Hz hazard by seismic source .................... 8-59

Figure 8.2-7c Topeka site, contribution to rock 10 Hz hazard by seismic source .................... 8-60

Figure 8.2-7d Topeka site, contribution to rock 5 Hz hazard by seismic source ...................... 8-61

Figure 8.2-7e Topeka site, contribution to rock 2.5 Hz hazard by seismic source ................... 8-62

Figure 8.2-7f Topeka site, contribution to rock 1 Hz hazard by seismic source ...................... 8-63

Figure 8.2-7g Topeka site, contribution to rock 0.5 Hz hazard by seismic source ................... 8-64

Figure 8.2-7h Topeka site, 10-4 and 10-5 rock UHRS ............................................................. 8-65

Figure 8.2-8 Chattanooga site, sensitivity of PGA rock hazard to 9 ground-motionequations. Solid curves show hazard for the Updated GMM; dashed curves showhazard for the EPRI (2004, 2006) G M M ......................................................................... 8-66

Figure 8.2-9 Chattanooga site, sensitivity of 10 Hz rock hazard to 9 ground-motionequations. Solid curves show hazard for the Updated GMM; dashed curves showhazard for the EPRI (2004, 2006) G M M ......................................................................... 8-67

Figure 8.2-10 Chattanooga site, sensitivity of 1 Hz rock hazard to 9 ground-motionequations. Solid curves show hazard for the Updated GMM; dashed curves showhazard for the EPRI (2004, 2006) G M M ......................................................................... 8-68

Figure 8.2-11 Sensitivity of hazard to aleatory uncertainty (logarithmic standarddeviation, or sigma). Note: This result was obtained using the approach in AppendixI of EPRI (2004), assuming a logarithmic slope of 3 for the hazard curve ....................... 8-69

XXXIX

Figure A. 1-1 Locations of seismic recording stations from GEOVision report (EPRI,2 0 13 a ) ....................................................................................................................... A -3

Figure A.1-2 Locations of seismic recording stations from the USGS (Kayen et al., in

p re ss ) ........................................................................................................................ A -3

Figure G.2.2-1 Map defining the Gulf Coast region ............................................................... G-35

Figure G.2.5-1 Frequency and magnitude-dependent portion of the aleatory uncertainty ...... G-36

Figure G.3.3-1 Logic tree for sites affected by both RLMEs and distributed-seismicityso urces ......................................................... . ....................................................... G -37

XL

EXECUTIVE SUMMARY

The EPRI (2004, 2006) Ground-Motion Model (GMM) Review Project was conducted duringthe period from March 8, 2012, to May 31, 2013, to provide the nuclear industry with an updateto the EPRI (2004, 2006) GMM for use in conducting probabilistic seismic hazard analyses(PSHAs) to respond to the U.S. Nuclear Regulatory Commission's (NRC's) Request forInformation (RFI) for existing nuclear facilities dated March 12, 2012. A Senior Seismic HazardAnalysis Committee (SSHAC) Level 2 study process with a number of Level 3 processenhancements was used (NUREG-2117) considering present-day NRC guidance for updating anaccepted existing seismic hazard model and balancing project-specific factors such as technicalcomplexity, regulatory requirements, and resource limitations with the need to ensure with a highlevel of confidence that the updated model represents present-day technical knowledge. Thepurpose of providing an extended executive summary is to convey the extended scope of theproject in somewhat greater detail.

This project was motivated by significant technical advances in predicting earthquake groundmotion during the past 10 years, triggering the need to review the EPRI (2004, 2006) GMM and,if necessary, to update the model for use by licensees of nuclear plants located in the Central andEastern United States (CEUS) in developing their responses to Near-Term Task Force (NTTF)Recommendation 2.1: Seismic. A key objective in planning the project was to implement astructured, unbiased process that included broad participation of the present-day GMM technicalcommunity, the regulator, and oversight groups to (1) define current seismological understandingof ground motion in the CEUS since the SSHAC study that developed the EPRI (2004, 2006)GMM, which began in 2002; (2) compile an up-to-date ground-motiondatabase; and (3) evaluatewhether the EPRI (2004, 2006) GMM required updating in light of the up-to-date database andpresent-day advances in the development of ground-motion-prediction equations (GMPEs).

For the purpose of defining the present-day state-of-practice for GMM, insights and perspectivesfrom recognized ground-motion experts and from ongoing GMM projects were obtained. Thiswas accomplished by means of conference calls, interviews, and a meeting at the offices of theU.S. Geological Survey (USGS). Table 2.1-1 lists the dates for these contacts and theprofessionals who participated, some of whom had participated in the SSHAC studies thatdeveloped the EPRI (2004, 2006) GMM. The observations and recommendations concerning thecurrent state of practice for GMM in the CEUS that came from these activities were the basis fordevelopment of the EPRI (2004, 2006) GMM Review Project Plan described in Chapter 2.

These due diligence activities were conducted during the period from October 2011 to March2012. During this period, interactions with the Pacific Earthquake Engineering Research (PEER)Center's NGA-East Project and the USGS National Seismic Hazard Mapping Project took placeto establish processes for productive cooperation with these important ongoing projects

XLI

throughout this study. The level of confidence that the Updated EPRI (2004, 2006) GMMrepresents present-day ground-motion-modeling practice has been enhanced by the broadparticipation of recognized seismologists and ground-motion experts from industry, government,and academia and by productive cooperation from participants in the PEER NGA-East Projectand the USGS National Seismic Hazard Mapping Project.

The EPRI (2004, 2006) GMM Review Project implemented an enhanced SSHAC Level 2 studyin order to provide a high level of assurance that the present-day data, models, and methods ofthe ground-motion modeling technical community were considered and that the center, body, andrange of technically defensible interpretations have been properly represented in the updatedmodel. The SSHAC process ensures thorough consideration of present-day knowledge anduncertainties of the larger technical community within a robust and transparent evaluation andassessment framework. Guidance for implementation of a SSHAC study is detailed in the NRC'sNUREG/CR-6372, Recommendations for Probabilistic Seismic Hazard Analysis: Guidance onUncertainty and Use of Experts, and NUREG-2117, Practical Implementation Guidelines forSSHA C Level 3 and 4 Hazard Studies.

The SSHAC methodology is accepted in present-day NRC's seismic regulatory guidance(Regulatory Guide 1.208) for ensuring that proposed seismic-design-basis ground motionsproperly represent uncertainties in data and scientific knowledge in compliance with therequirements of the seismic regulation 10 CFR Part 100.23 ("Geologic and Seismic SitingCriteria"). Therefore, the goal of the SSHAC methodology is the proper and completerepresentation of knowledge, data, and modeling uncertainties in the seismic-sourcecharacterization (SSC) and ground-motion characterization (GMC) inputs to the PSHA.Regulatory Guide 1.208 accepts the CEUS SSC and ground-motion characterization (GMC)models for the CEUS to be the starting basis for site-specific PSHAs at sites within the regionand provides guidance for site-specific implementation. A SSHAC Level 3 study is required fordevelopment of a regional SSC or GMC model to be accepted as an element of the NRC'sseismic regulatory guidance. A Level 2 study may be used for evaluating whether an existingaccepted regional model requires updating for a specific application and, if determined to berequired, for updating the model for PSHA at a specific site or another specific use.

A SSHAC assessment process consists of two core sequential activities: evaluation andintegration. For a Level 2 study, these activities, which are conducted by a Technical Integration(TI) Team under the leadership of a TI Lead and the Project Manager, are described in NUREG-2117 as follows:

The fundamental goal of a SSHAC process is to carry out properly and documentcompletely the activities of evaluation and integration, defined as:

Evaluation: The consideration of the complete set of data, models, and methods proposedby the larger technical community that are relevant to the hazard analysis.

Integration: Representing the center, body, and range of technically defensibleinterpretations in light of the evaluation process (i.e., informed by the assessment ofexisting data, models, and methods.

Implementation of each of the assessment and model-building activities of the EPRI (2004,2006) GMM Review Project was carried out consistent with the evaluation and integration stepsof a SSHAC Level 2 process. The specific roles and responsibilities of all project participants

XLII

were defined in the Project Plan (EPRI, 2012). The technical assessments were made by the TITeam, which had the principal responsibility of evaluation and integration. The DatabaseManager and other technical support individuals assisted in the development of work products.Consistent with the SSHAC Level 2 implementation guidance, Resource and Proponent Expertsparticipated in interviews. They continued technical interchange with the TI Team throughoutthe project. Also, the Resource and Proponent Experts presented their data and current modelsand interpretations at the workshop on October 17, 2012. The Participatory Peer Review Panel(PPRP) provided continuous interactive review of both the SSHAC Level 2 processimplementation and the evolving technical assessments. Project communication with stakeholderobservers assured proper integration of the activities of all participants.

For this project, the SSHAC Level 2 assessment process was enhanced by the implementation ofa number of SSHAC Level 3 study processes. For example, the PPRP was engaged at projectinception, including for development of the Project Plan and participation in the feedbackworkshop. Both the PPRP and the Resource and Proponent Experts provided extensive feedback.A comparison of the activities conducted during the EPRI (2004, 2006) GMM Review Projectwith those recommended in the SSHAC guidelines shows that the current standards of practicefor a SSHAC Level 2 process were fully met and the activities of evaluation and integration werecompletely documented. The SSHAC Level 2 assessment process and implementation arediscussed in depth in Chapter 3 of this report.

The objective of the project was to review the EPRI (2004, 2006) GMM and, if necessary, toupdate the model. Both the evaluation of whether the existing GMM should be updated and theimplementation of the update study were carried out retaining the conceptual-structuralframework of the EPRI (2004, 2006) GMM. The following steps were implemented:

1. Development of an up-to-date database.

2. Testing the EPRI (2004, 2006) GMM using the up-to-date database to determine whether itrequired updating.

3. Evaluation: Consideration of current data, models and methods that have been proposed bythe larger technical community using the up-to-date database.

4. Integration: Assessment and incorporation of uncertainties representing the center, body, andrange of technically defensible interpretations.

5. Adoption of new approaches to systematically document input from the larger technicalcommunity and to evaluate all data considered in order to increase transparency.

6. Engagement of all stakeholders and a robust peer review.

Highlights of the EPRI (2004, 2006) GMM review and update project are presented below.

STUDY AREA

The project study region (Figure 1) is the same as the region for the 2012 CEUS SSC model(EPRI/DOE/NRC, 2012). For the GMM, the project study region is divided into two sub-regions:the Midcontinent Region and the Gulf Region. The Updated EPRI (2004, 2006) GMM isapplicable to all sites within the project study region. The western boundary is locatedapproximately along the foothills of the Rocky Mountains at longitude 105'W. On the north, the

XLIII

study region extends a minimum of 322 km (200 mi.) beyond the U.S.-Canadian border. On theeast and south, only areas that lie within the continental crust are included. The GMM does notapply to areas outside the study region boundaries, including the Western United States (WUS),Canada, most of Mexico, and the Caribbean Plate boundary area.

PRODUCTS OF THE PROJECT

Updated EPRI (2004, 2006) Ground-Motion Model

The Updated EPRI (2004, 2006) GMM was developed retaining the conceptual framework of theEPRI (2004) GMM for the Midcontinent Region and Gulf Region shown on Figure 1. Theupdated assessment was accomplished with the following major steps:

Explanation

* Test Sites (1)• • Q •r"'lCEUS study area (1)

Midcordinent Region (2)Gul Source Region (2)

Sources: 1F CEUS Project,EPRI (2012); 2. This study

Base map: GEBCO 2008 Grid

N 0 ft0rn.

A 0 , 1400 1

Figure I

Study area showing ground-motion model sub-regions and test sites

" Prepare an up-to-date database of ground-motion recordings for use in testing the availableCentral and Eastern North America (CENA) GMPEs, using as a starting point the ground-motion database assembled by the NGA-East Project.

• Process the assembled database to ensure uniformity parameters and correction for near-surface site classifications throughout the study region, check the consistency of correcteddata, and adjust, if necessary.

" Identify GMPEs and assign GMPEs to clusters by reviewing the literature, conductinginterviews, and holding a workshop with current ground-motion experts.

XLIV

" Establish analytical and empirical approaches for adjusting recording-site conditions usingshear-wave-velocity measurements at strong-motion recording sites.

" Compute GMPE and cluster weights.

" Evaluate the epistemic uncertainty.

" Update the EPRI (2006) aleatory variability model.

The paragraphs that follow provide summaries regarding the evaluation and integration activitiesperformed for development of the Updated EPRI (2004, 2006) GMM and describing additionalproducts of the project.

Hazard Input Document

The hazard input document (HID) in Appendix G provides the documentation necessary forusers to implement the Updated EPRI (2004, 2006) GMM in a PSHA. The HID contains all theinformation required for a future use of the model within a PSHA, but it does not include thetechnical basis or justification for the elements of the model. The purpose of the HID is to ensurethat the expert assessments made by the TI Team are captured fully and are accurately andtransparently communicated for use by the designated hazard analyst in a PSHA for a specificsite. As part of this EPRI (2004, 2006) GMM Review Project, the HID was used by the hazardanalyst, a member of the TI Team, to carry out hazard calculations at seven demonstration sites.

Documentation of Literature Reviews, Expert Interviews, and PPRP Correspondence

In order to demonstrate the structured and systematic evaluation of the range of diverseinterpretations from the larger technical community in a structured and systematic way, the TITeam conducted literature reviews and both interviewed Resource and Proponent Experts, someof whose work was either not published or was awaiting publication. Appendix B provides thedocumentation for literature reviews, including literature review tables that document the resultsof the reviews by the TI Team. Appendix C provides the documentation for the interviewsconducted by the TI Team with Resource and Proponent Experts who are working on CEUSground-motion modeling. The TI Team obtained information from copies of papers under reviewor in press, as well as from updates about these experts' ongoing work. Appendix H and thePPRP Final Report present the PPRP input throughout the project.

Project Database

The EPRI (2004, 2006) GMM Review Project database was developed to compile, organize, anddocument the data sets and resources that have been utilized during the course of this project.Development of the project database began at the inception of the project and provided TI Teammembers with the current version of the NGA-East ground-motion database, the shear-wave-velocity database for seismic recording stations, and an up-to-date set of data, maps, and figures.The Database Manager established a File Transfer Protocol (FTP) site for the TI Team, ProjectManager, and other participants in the study to access the project database. Appendix A providesdetails regarding the project database.

Shear- Wave- Velocity Measurements at Seismic Recording Stations

Shear-wave-velocity measurements were obtained for a suite of seismic recording sites in theCEUS from which usable recordings were available; the measurements were used for uniformly

XLV

correcting the updated database. EPRI (2013a) describes the investigations conducted from May15 and July 19, 2012, to develop S-wave velocity (Vs) models to a depth of 30 m (or more) andto estimate the average shear-wave velocity of the upper 30 m (Vs 30) at 33 seismic recordingstations located in the CEUS from which seismic recordings were available.

Additionally, the USGS measured shear-wave velocity at 24 seismic recording stations during2011 and 2012 (Kayen et al., 2013). The results of these measurements were provided to theEPRI (2004, 2006) GMM Review Project as part of the productive cooperation between EPRIand the USGS established for the project. A summary of results from each of the recording sitelocations is provided in Chapter 4.

Based on these investigations, including overlapping shear-wave-velocity measurements atstations ET.SWET and US.CBN, the following results were obtained for support of ground-motion modeling in the CEUS.

" Shear-wave velocity for hard rock sites in general are, lower than the CEUS reference-rockvelocity of 2,800 m/s, which is assumed for developing GMPEs; shear-wave velocitiesapproaching or equal to the reference-rock velocity were encountered at depths greater than30 m at some sites.

* Velocity inversions exist at some sites (i.e., shear-wave velocity of rock over a depth intervalin the profile can be higher than that for an interval that is immediately below it).

" Information on the depth of seismograph instrument emplacement was obtained for therecording stations.

* The near-surface geology at the recording stations can be highly variable and lateral velocityvariation is an important issue at many sites.

" The effects of different configurations of the velocity measurement instrumentation, lateralvariation in the properties of near-surface strata, and local variation in the depth of watertable must be taken into account in evaluating Vs30 measurements.

The NGA-East profile database was also used. This database contains Vs 30 estimates compiledfrom existing literature.

EPRI (2004, 2006) GROUND-MOTION MODEL (GMM)

Framework

The Updated EPRI (2004, 2006) GMM retained the structural framework developed for theEPRI (2004) GMM development. The EPRI (2004) study essentially updated a study performedby EPRI almost 20 years earlier, in 1993, to evaluate and quantify uncertainty in ground-motionmodeling in the CEUS and to develop a CEUS GMM that incorporated both epistemic andaleatory uncertainty in seismological aspects of ground-motion prediction given the databaseavailable at that time. Although the study preceded publication of the SSHAC Guidance (Budnitzet al., 1997), it was conducted following a process comparable to a SSHAC Level 3 assessment.

Consistent with the SSHAC Guidance for a Level 3 assessment, the EPRI (2004) GMM projectteam consisted of a three-person TI Team, including experienced ground-motion-modelingexperts, a six-person expert panel, and a PPRP. The expert panel consisted of proponent GMPE

XLVI

development experts who broadly represented the range of seismological attributes of the-existing proponent GMPEs. The PPRP included nationally recognized experts in ground-motionmodeling for engineering application, as well as in seismic hazard modeling applicable toseismic regulation.

Also consistent with the SSHAC Guidance, a series of three workshops was held fordevelopment of the EPRI (2004) GMM. TI Team working meetings took place as neededbetween workshops. An important outcome of Workshop 1 was consensus that simply weightingthe technically defensible GMPEs based on the degree to which each predicts the available datawould not adequately capture epistemic uncertainty. Considering approaches for structuring theevaluation and integration of the GMM to more fully understand and capture epistemicuncertainty, a structure evolved from the workshop of grouping the GMPEs into four clustersbased on similar seismological attributes (primarily representation of the earthquake source).This structure permitted evaluation and assessment of within-cluster epistemic uncertainty, aswell as epistemic uncertainty based on an assessment of the seismologic attributes of the fourclusters. Implementation of the cluster structure resulted in four model clusters, defined asSingle-Corner Stochastic (Cluster 1), Double-Corner Stochastic (Cluster 2), Hybrid (Cluster 3)and Finite-Source/Green's Function (Cluster 4). The 13 technically defensible GMPEs at thetime were grouped into the four clusters shown in Table 1. EPRI (2004) GMM regionalization ofthe CEUS is shown on Figure 2.

Table 1

EPRI (2004) Ground-Motion Models Grouped by Cluster

Cluster Model Type Models1

1 Single-Corner Stochastic Hwang and Huo (1997)Silva et al. (2002) - SC-CS

Silva et al. (2002) - SC-CS-SatSilva et al. (2002) - SC-VS

Toro et al. (1997)Frankel et al. (1996)

2 Double-Corner Stochastic Atkinson and Boore (1995)Silva et al. (2002) DC

Silva et al. (2002) - DC-Sat

3 Hybrid Abrahamson and Silva (2002)

Atkinson (2001) and Sadigh et al. (1997)

Campbell (2003)

4 Finite-Source /Green's Function Somerville et al. (2001)

SC = single-corner; DC = double-corner; CS = constant stress; VS = variable stress; Sat = saturation.

XLVII

EPRI (2006) Aleatory Model Study: Update of the EPRI (2004) Aleatory Model

The standard deviation (sigma) developed in the EPRI (2004) ground-motion study was muchlarger than shown by later studies that used large western data sets of ground-motionmeasurements. In consequence, EPRI performed a study for the purpose of assessing the properaleatory variability (sigma) to assign to CENA GMMs (EPRI, 2006). That study, which updatedthe EPRI (2004) study, was conducted using a SSHAC Level 2 assessment process. Thepreliminary results available from NGA-West 1 constituted the primary data for the study. Thestudy concluded that empirically based estimates of sigma using data from active tectonicregions are appropriate with proper adjustment for the CEUS region. In the EPRI (2006) study,alternative models for the total standard deviation (combined intra-event and inter-event) weredeveloped and applied to the CEUS.

GUFCOAST

Figure 2EPRI (2004) regionalization

Discussion of EPRI (2004, 2006) GMM Update

The TI Team for the EPRI (2004, 2006) GMM Review Project concluded that the model shouldbe updated for the following reasons:

" Seven of the 13 GMPEs underlying the EPRI (2004, 2006) GMM are no longer supported bytheir developers.

" Three new GMPEs for CENA have been developed since the completion of the EPRI (2004)work. Furthermore, these 3 GMPEs are currently in their second generation of development,which suggests that they are robust.

" The CENA ground-motion database is significantly larger now than it was when the EPRI(2004) study was completed. This is a consequence of the occurrence of a number ofearthquakes during the last decade (including the Mineral, Virginia, Sparks, Oklahoma, Valdes Bois, Quebec, and Mt. Carmel, Illinois, earthquakes), and it is also due to the data

XLVIII

collection efforts of the NGA-East Project. In fact, the NGA-East CENA database availableto this project is five times larger than the EPRI (2004) database.

" Comparisons to the database described above indicate that the EPRI (2004, 2006) GMM overpredicts ground motions at some magnitude-distance and structural frequency ranges that areimportant to nuclear power plant (NPP) PSHA.

" The aleatory portion of the EPRI (2004, 2006) GMM was based primarily on preliminarymodels from the NGA-West 1 study (Power et al., 2008). These preliminary models havebeen superseded by the final NGA-West 1 model released in 2008 and by the preliminaryresults of the ongoing NGA-West 2 model study (Bozorgnia et al., 2012).

Based on the reviews and discussions with researchers, the continued use of each of the GMPEsincluded in the EPRI (2004) study was evaluated and new candidate GMPEs were identified.The results of these evaluations are shown in Table 2 where the Updated EPRI (2004, 2006)GMM clusters, models, and weights are shown.

Table 2Updated EPRI (2004, 2006) GMM Clusters and Models

Model Types and Cluster Weights(repeated large-magnitude earthquake

Cluster sources/area earthquake sources) Models

1 Single-Corner Brune Source Silva et al. (2002) - SC-CS-Sat'(0.15/0.185) Silva et al. (2002) - SC-VS 1

Toro et al. (1997)

Frankel et al. (1996)

2 Complex/Empirical Source Silva et al. (2002) - DC-Sat

-R- 1 Geometrical spreading Atkinson (2008) with 2011 modifications

(0.31/0.383) (A08')

3 Complex/Empirical Source Atkinson-Boore (2006) with 2011

-R- 1.3 Geometrical spreading modifications (AB06')

(0.35/0.432) Pezeshk et al. (2011)

4 Finite-Source /Green's Function Somerville et al. (2001); slightly different

(0.19/0) models for rifted and nonrifted (not used fordistributed seismicity sources with largecontribution from M < 6)

SC = single-corner; DC = double-corner; CS = constant stress; VS = variable stress; Sat = saturation.

Treated as one model for calculation of weights.

KEY ELEMENTS OF THE UPDATED EPRI (2004, 2006) GMM

The following is an overview of the methodology used to develop the Updated EPRI (2004,2006) GMM. Clusters 1-4 for the Updated EPRI (2004, 2006) GMM are described in Table 2.Chapters 5 through 7 provide details.

XLIX

SSHA C Study Level

Because this study is an update to an accepted existing SSHAC Level 3 GMM, a SSHACLevel 2 assessment process was selected as the appropriate level. A number of SHHAC Level 3features were also implemented in this project, such as the engagement of a PPRP from the startof the project, review and acceptance of the Project Plan, and an in-person feedback workshop.Both the PPRP and the Resource and Proponent Experts provided extensive feedback in formalinterviews and in an interactive workshop.

Data

This project took advantage of two significant data collection efforts, namely, the NGA-EastProject effort, which included the uniform processing of strong-motion and seismograph data,and the EPRI-sponsored effort, which characterized site conditions at a number of recordingstations (the latter supplemented by a parallel USGS effort that provided data for additionalstations). Chapter 4 provides the shear-wave-velocity data from both collection efforts. Thestation site data were used to adjust the strong-motion data to reference site conditions, using twoalternative approaches. Appendix A provides details regarding the database for this study.Chapter 6 of this report describes development and corrections to the database, and Section 7.2describes the development of the final ground-motion database used in this study, includingdetails of the NGA-East database and the processing steps applied to develop the final projectdatabase used for the update to the EPRI (2004, 2006) GMM.

Structure of the Updated GMM

The Updated GMM retained the structure of the EPRI (2004) GMM, which grouped thecandidate GMPEs into four clusters according to their seismological characteristics, weightingthe GMPEs within each cluster according to their consistency with the data, representing eachcluster by three fitted GMMs (5th percentile, median, and 95th percentile), and assessing clusterweights based on consistency with observed data and seismological attributes of the GMMswithin each cluster.

There are some differences in implementation in the Updated GMM, however. Some of thesedifferences represent adjustments for advances in ground-motion prediction; others representimprovements in methodology for model development. In particular, the set of candidate GMPEs*has changed to because (1) some of the GMPEs considered by the EPRI (2004) study are nolonger supported by their developers and proponents, and (2) new GMPEs are currentlyavailable. The new GMPEs necessitated updating the definition of Clusters 2 and 3 because themost salient grouping of the candidate GMPEs for these clusters was their difference ingeometrical spreading. Also, the calculation of consistency with the data was changed to alikelihood-based formulation, which is more flexible (e.g., it allows for consideration of single-station correlation in adjustment factors) and has a strong basis in theory. In addition, thecharacterization of within-cluster epistemic uncertainty was modified to avoid unquantifiedcorrelations, and to take advantage of the more abundant data in constraining the predictions atlow magnitudes, and to account for uncertainty in magnitude scaling in a more direct manner.The clusters and weights (for area sources and repeated large-magnitude-earthquake sources,respectively) for the Updated EPRI (2004, 2006) GMM are shown in Table 2.

L

Model for Aleatory Uncertainty

The EPRI (2006) model for aleatory uncertainty (sigma) was based on preliminary NGA-West 1models for sigma (Power et al., 2008) from the WUS, adjusted to account for differences inproperties of the earth's crust between WUS and CEUS. The updated model for this studyincorporates nearly final NGA-West 2 aleatory models (Bozorgnia et al., 2012), with the sameadjustments for differences between WUS and CEUS. In that sense, the updated model foraleatory uncertainty represents a straightforward update to the EPRI (2006) aleatory model,where elements that have been superseded are replaced by their natural successors. The aleatoryvariability model developed by Atkinson et al. (2012) for updating the seismic hazard map ofCanada is compared with the model developed in this study on Figure 3. A comparison of thetotal aleatory variability for the EPRI (2004) GMM and the Updated EPRI (2004, 2006) GMM isshown on Figure 4.

----- Atkinson et al. (2012)

0.9 EPRI(2013)M5•" EPRI (2013) M6

0.8 EPRI (2013) M7

0.7

0.6 -

0.5

0 .4 . . . ..0.1 10 100

Frequency (Hz)

Figure 3Comparison of aleatory variability model developed by Atkinson et al. (2012) with the modeldeveloped from this study

LI

1

0.9

". 0.8 -

'.. __ _ _._.... _-.- __0.7 L

50.60 - - - EPRI (2006)

0.5 - Update M5-Update M6

0.4 - Update M7 _

0.1 1 10 100

Frequency (Hz)

Figure 4Total aleatory variability for EPRI (2006) GMM and Updated EPRI (2004, 2006) GMM

Model for Gulf Region

Section 7.11 documents procedures for modifying the Updated GMM for site-seismic sourcegeometries where seismic wave travel paths are primarily through Gulf Coast. This modificationaccounts for differences in anelastic attenuation between the Midcontinent and the Gulf Coastsub-regions and updates the approach developed by EPRI (1993), which was adopted for theEPRI (2004) GMM. The updated geographical boundary between the Midcontinent and GulfRegions is shown on Figure 1; the geographical boundary used for the EPRI (2004) GMM isshown on Figure 2.

In cases where a seismic source defined in the CEUS SSC Model (EPRIDOE/NRC, 2012) iswholly or partially within one region and the site for which PSHA is to be performed is withinthe other, the selection between the Midcontinent and Gulf model is not straightforward. It isrecommended that the hazard analyst select the region that contains the majority of the travelpath, defined by the minimum distance from the source to the site. It is also appropriate to pro-rate the Midcontinent and Gulf ground-motion amplitudes, taking into account the fraction of thesource-site path that is contained within each region.

SEISMIC HAZARD CALCULATIONS AT TEST SITES

Overview

The Updated EPRI (2004, 2006) GMM was used to calculate seismic hazard at the seven testsites examined under the CEUS SSC Project (EPRIIDOE/NRC, 2012). Comparisons of hazardresults shown in Chapter 8 of this report illustrate differences in hazard between the EPRI (2004,2006) GMM and the Updated EPRI (2004, 2006) GMM. All the calculations described in this

LII

chapter were made for demonstration purposes only and should not be used for design oranalysis decisions for any engineered facility.

The seismic hazard calculated for comparative purposes are for CEUS reference-rock conditions.CEUS reference rock is defined by shear-wave velocity of 2,800 m/s (9,200 ft/s) and kappa of0.006 seconds. Locations of the seven test sites are shown on Figure 1.

When the geometry of the earthquake rupture is defined, the Updated EPRI (2004, 2006) GMMuses distance to the surface projection of the rupture (Joyner-Boore distance) and closest distanceto the rupture (depending on the specific equation within the model). When (for seismic hazardcalculations) the rupture geometry is unknown and the earthquake is represented as a point, theEPRI (2004) report includes correction terms for the distance measures and for the aleatorystandard deviation, in order to modify these parameters for point-source conditions. Thesemodifications were implemented within the seismic hazard calculations, for both the EPRI(2004, 2006) GMM and the Updated EPRI (2004, 2006) GMM.

The seismic hazard calculations performed for this report were made with the LCI THAZsoftware code. This software is different from the software used to calculate and report results inthe CEUS SSC Project (EPRIIDOE/NRC (2012), but it gives seismic hazard results that are veryclose to those in that project. Any differences in the results observed are attributable todifferences in the ground-motion equations.

Observations

The following observations are based on comparisons of the seismic hazard curves in Chapter 8.

" There is a decrease in ground motion hazard at all spectral frequencies, but not at peakground acceleration (PGA), for the test sites in both the Midcontinent Region and GulfRegion when the Updated EPRI (2004, 2006) GMM is used with the 2012 CEUS SSCmodel. For PGA, equations for the Updated EPRI (2004, 2006) GMM indicate a range ofseismic hazards similar to the range of seismic hazards obtained using the EPRI (2004, 2006)GMM.

" The amount of reduction in ground motion varies by spectral frequency and test site.

* At test sites located in the Gulf Region, some of the difference in hazard can be attributed tothe updated geometry of the Gulf Region, compared with the geometry defined in the EPRI(2004, 2006) GMM. Chapter 8 provides details of the changes between the EPRI (2004,2006) GMM and the Updated EPRI (2004, 2006) GMM for the seven test sites.

All results from the seismic hazard calculations for each of the seven test sites, including adetailed discussion, are provided in Chapter 8. Details of differences in hazard between the EPRI(2004, 2006) GMM and the Updated EPRI (2004, 2006) GMM for the seven test sites are alsoprovided in Chapter 8.

CONCLUSIONS

The conclusions from the EPRI (2004, 2006) GMM Review Project are as follows:

LIII

1. The EPRI (2004, 2006) GMM Review Project demonstrates that a SSHAC Level 2 processupdate of an accepted existing SSHAC Level 3 study is feasible by maintaining theconceptual/structural framework of the original SSHAC Level 3 study.

2. The Updated EPRI (2004, 2006) GMM was developed using the conceptual structuredeveloped for the EPRI (2004) GMM and updating the model considering technicallydefensible present-day GMPEs and the present-day ground-motion database, 80% of whichwas obtained after the EPRI (2004) study.

3. Each of the steps in the SSHAC Level 2 process was followed along with severalenhancements performed for this study.

4. The center, body, and range (CBR) of technically defensible interpretations (TDI) have beencaptured and appropriately represented in the Updated EPRI (2004, 2006) GMM.

5. Participation of recognized seismologists and ground-motion experts from industry,government, and academia, engagement of the PPRP from the beginning of the study, andthe productive cooperation from the PEER Center, members of the NGA-East Project, andthe USGS contribute to assurance that the Updated GMM properly represents present-daystate of practice.

REFERENCES

Atkinson, G., with input from Adams, J., Rogers, G., Onur, T., and Assatourians, K., 2012.White paper on Proposed Ground-Motion Prediction Equations (GMPEs) for 2015 NationalSeismic Hazard Maps, Final Version, November; available at http://www.seismotoolbox.ca/GMPEtables2012/ri 2_GMPEs9b.pdf.

Bozorgnia, Y., Abrahamson, N.A., Campbell, K.W., Rowshandel, B., and Shantz, T., 2012.NGA -West2: A comprehensive research program to update ground motion prediction equationsfor shallow crustal earthquakes in active tectonic regions, Proceedings 15 World Conference onEarthquake Engineering, Lisbon Portugal, Sept. 24-28, paper WCEE2012_2572.

Budnitz, R.J., Apostolakis, G., Boore, D.M., Cluff, L.S., Coppersmith, K.J., Cornell, C.A., andMorris, P.A., 1997. Recommendations for Probabilistic Seismic Hazard Analysis: Guidance onUncertaintv and Use of Experts, Report NUREG/CR-6372, Lawrence Livermore NationalLaboratory, sponsored by the U.S. Nuclear Regulatory Commission, U.S. Department of Energy,and Electric Power Research Institute.

Electric Power Research Institute (EPRI), 1993a. Guidelines for Determining Design BasisGround Motions, EPRI Report TR-102293, Research Project 3302, Final Report, November,Palo Alto, Calif.

Electric Power Research Institute (EPRI), 2004. CEUS Ground Motion Project Final Report,EPRI Report 1009684, December, Palo Alto, Calif.

Electric Power Research Institute (EPRI), 2006. Program on Technology hInovation: Truncationof the Lognormal Distribution and Value of the Standard Deviation/br Ground Motion Modelsin the Central and Eastern United States, EPRI Report 1013105, Technical Update, February,Palo Alto, Calif.

LIV

Electric Power Research Institute (EPRI), 2013a. EPRI (2004, 2006) Ground-Motion Model(GMM) Review Project.- Shear Wave Velocity Measurements at Seismic Recording Stations,EPRI Report 3002000717, Palo Alto, Calif., April.

Electric Power Research Institute (EPRI), 2013b. Seismic Evaluation Guidance: Screening,Prioritization and Implementation Details (SPID) for the Resolution of Fukushima Near-TermTask Force Recommendation 2.1: Seismic, EPRI Report 1025287, Palo Alto, Calif.

Electric Power Research Institute, U.S. Department of Energy, and U.S. Nuclear RegulatoryCommission (EPRI/DOE/NRC), 2012. Technical Report: Central and Eastern United StatesSeismic Source Characterization for Nuclear Facilities, NUREG-2115.

Kayen, R.E., Carkin, B.A., Corbett, S.C., Zangwill, A.S., Lai, L., and Estevez, I., 2013 (in press).Seismic Shear- Wave Velocity and Ground Motion Amplification Factors for 50 Sites Affected bythe Mineral, Virginia M5.8 Earthquake of 23 August 2011, U.S. Geological Survey, Open-FileReport 2013

Power, M., Chiou, B., Abrahamson, N., Bozorgnia, Y., Shantz, T., and Roblee, C., 2008. Anoverview of the NGA Project, Earthquake Spectra 24 (1), 3-21.

U.S. Nuclear Regulatory Commission (U.S. NRC), 2007. Regulatory Guide 1.208." Performance-Based Approach to Define the Site-Specific Earthquake Ground Motion, Office of NuclearRegulatory Research, March.

U.S. Nuclear Regulatory Commission (U.S. NRC), 2012. Letter to All Power Reactor Licenseeset al., "Request for Information Pursuant to Title 10 of the Code of Federal Regulations 50.54(f)Regarding Recommendations 2.1, 2.3 and 9.3 of the Near-Term Task Force Review of Insightsfrom the Fukushima Dai-Ichi Accident," March 12.

LV

PPRP FINAL REPORT #7EPRI GMM REVIEW PROJECT

May 29, 2013

Robert P. Kassawara Lawrence A. SalomoneEPRI Senior Project Manager Technical Project ManagerElectric Power Research Institute Electric Power Research Institute3420 Hillview Avenue 3420 Hillview AvenuePalo Alto, CA 94304 Palo Alto, CA 94304

Gentlemen:

Reference: EPRI (2004, 2006) Ground Motion Model Review Project.- Participatory PeerReview Panel Final Report (PPRP Report #7)

This letter constitutes the final consensus report of the Participatory Peer Review Panel (PPRP)l("the Panel") for the EPRI (2004, 2006) Ground Motion Model Review Project (the "GMMReview Project" or "the Project").

The four Panel members (Walter J. Arabasz, Brian Chiou, Richard C. Quittmeyer, andRobert B. Whorton) participated in the Project in a manner fully consistent with the SSHACGuidance 2 for a participatory peer review. The Panel was continually engaged in all phases andkey activities of the Project's implementation.

CONCLUSIONS

1. The exemplary implementation of a Senior Seismic Hazard Analysis Committee(SSHAC) Level 2 process in this Project allows us to confidently endorse its proceduralaspects.

2. We concur that the full ranges of relevant data, models, and methods proposed by thelarger technical community have been duly considered by the Technical Integration (TI)Team in their assessment and development of an Updated EPRI (2004, 2006) GroundMotion Model (GMM).

All acronyms used in this report are defined in the Appendix.

2 Budnitz, R. J., G. Apostolakis, D. M. Boore, L. S. Cluff, K. L. Coppersmith, C. A. Cornell, and P. A.

Morris, 1997. Recommendations for Probabilistic Seismic Hazard Analysis: Guidance on Uncertaintyand the Use of Experts (known as the "Senior Seismic Hazard Analysis Committee Report," or the"SSHAC Guidance"). NUREG/CR-6372, U. S. Nuclear Regulatory Commission. TIC; 235076.Washington, DC.

LVII

3. We concur that, in responding to our review comments on the draft Project Report, alltechnical assessments have been adequately defended and documented by the TI Team.

4. Based on our observation of the implementation of the SSHAC Level 2 process and ourreview of the technical bases and justifications provided by the TI Team, the PPRPconcurs that the Updated EPRI (2004, 2006) GMM, developed to be consistent with theconceptual framework of the existing EPRI (2004, 2006) GMM, appropriately capturesthe center, body, and range (CBR) of technically-defensible interpretations (TDI).

BACKGROUND

Summary of PPRP Engagement

Consistent with the SSHAC Guidance for a participatory peer review, the Panel engaged incontinual peer-review activities throughout the entire project period-from development of theProject Plan (March-June 2012) through production of draft and final versions of the ProjectReport (April-May 2013). The Panel, collectively and individually, fully understood theSSHAC Guidance for a structured participatory peer review and the requirements for a SSHACLevel 2 assessment process. We interacted extensively with the TI Team and Project Managerthroughout the Project, and diligent efforts were made by the Project Manager to keep usappropriately informed.

The Panel provided written and oral peer-review comments on both technical and processaspects at several stages of the Project's evolution. Our written comments are documented in sixPPRP reports reproduced in Appendix H of the Project Report.

Key PPRP activities included the following:

" Detailed review of the draft Project Plan (PPRP Report #1)

" Participation as observers, and occasionally as resource experts when requested by the TITeam and Project Manager, in each of the TI Team's five formal working meetings, heldbetween March and August 2012

" Critical review of information and arguments presented by the TI Team and ProjectManager at Working Meeting #5 on August 14, 2012, and PPRP agreement with the TITeam's recommendation to update the EPRI (2004, 2006) GMM (PPRP Report #2)

" Involvement in the October 17, 2012, Project Workshop: "Interactions with TechnicalCommunity"-including advising in the planning stage, participating collectively as areview panel during the workshop (and individually as resource experts when requestedby the TI Team and Project Manager), and submitting a written report of the Panel'sobservations and recommendations following the workshop (PPRP Report #3)

" Peer-review and written comments on the draft updated GMM presented at the PPRPClosure Briefing on February 13, 2013, together with general comments on the TITeam's Intermediate Document of January 18, 2013 (PPRP Report #4)

" Multiple interactions with the TI Team and Project Manager, following on the PPRPClosure Briefing, leading to a final version of an Updated EPRI (2004, 2006) GMM in

LVIII

late March 2013 along with PPRP concurrence with the Updated GMM (PPRP Report#5)

" Extensive, critical peer-review of the draft Project Report in May 2013 (PPRP Report #6)

" In addition to the workshop and five working meetings noted above, direct PPRPinteraction with the TI Team and Project Manager in more than 13 conference calls, allproviding opportunities for timely comments on technical and process issues

Responsibilities of the PPRP at Closure

Upon closure of the Project, the PPRP has the responsibility, under SSHAC guidelines, toaddress the following (see, for example, section 3.6.8 ofNUREG-21173):

" Whether the Project has conformed to the recommendations of a SSHAC Level 2assessment process

" Whether the full ranges of data, models, and methods have been duly considered in the TITeam's assessment

" Whether all technical assessments have been adequately defended and documented by theTI Team

" Whether the updated GMM captures the CBR of TDI

DISCUSSION

Implementation of a SSHAC Level 2 Process

Chapter 3 of the Project Report provides a full description of how a SSHAC Level 2 assessmentprocess was implemented in the Project. The summary reflects evident attention to ensuringcompliance with SSHAC guidelines. The SSHAC Level 2 process implemented for the Projecthas been exemplary, in our judgment. The PPRP has also been impressed with the execution ofthe Project in terms of adherence to schedule and the timely completion of tasks.

The decision by the Project Manager and the Sponsor to enhance the SSHAC Level 2 process byinvolving a PPRP has contributed significantly, in our view, to the Project's success. We thankthe Project Manager and the TI Team for actively seeking, respecting, and duly acting upon ourcomments and recommendations relating both to process and technical issues throughout theProject.

Evaluation of Data, Models, and Methods

We observed that the TI Team adopted a structured systematic approach to perform the SSHACevahlation activity of considering the complete set of relevant data, models, and methodsproposed by the larger technical community. The evaluation activity notably included multi-stage interactions with the larger technical community-including interviews, conference calls

3 U.S. Nuclear Regulatory Commission (NRC), 2012. Practical Implementation Guidelines for SSHAC Level 3and 4 Hazard Studies, NUREG-2117, Rev. 1, NRC Office of Nuclear Regulatory Research.

LIX

and meetings during the pre-Project "due diligence" stage that helped shape the Project Plan;close coordination with the NGA-East Project and the U.S. Geological Survey's NationalSeismic Hazard Mapping Project; a thorough literature review; one-on-one interviews bymembers of the TI Team with 11 resource and proponent experts; and the October 2012interaction workshop together with follow-up feedback.

It is germane to note that for the purpose of updating the EPRI (2004, 2006) GMM, the TI Teamadopted an approach intended to be consistent with the conceptual framework of the existingEPRI GMM. Based on our observations of the process involved in the Project, including directcomments made by ground motion experts at the October 2012 workshop, we are confident thatthe TI Team has duly considered and evaluated all available data, methods, and models that arerelevant.

Documentation-the Project Report

The SSHAC Guidance emphasizes the critical importance of thorough and adequatedocumentation of the Project's process and results-for understanding and use by others in thetechnical community, by later analysis teams, and by the project sponsor. The Panel wascommitted to ensuring (1) that the documentation of technical details associated with the ProjectReport was clear and complete and (2) that process aspects of the Project were transparent andaccurately described in the Project Report. The PPRP also has the companion responsibility toensure that all of the TI Team's technical assessments have been adequately defended anddocumented. To be clear, the SSHAC Guidance charges the PPRP to judge the adequacy of thedocumented justification for the Updated GMM and its associated logic-tree weights; intellectualownership of the Updated GMM and its inputs belongs to the TI Team.

The Panel completed a rigorous review of the draft Project Report. We provided a lengthycompilation of review comments on the entire report, including appendices (PPRP Report #6),and we also provided marked-up Microsoft Word files with extensive editorial comments andsuggestions for improving the report. Further, we held a conference call with the TI Team andProject Manager to ensure a clear understanding of our review comments. Our formal reviewcomments were designated as either mandatory (to be addressed by the TI Team in finalizing theProject Report) or non-mandatory (to be handled by the TI Team as feasible and at theirdiscretion).

Production of the final Project Report faced a firm deadline. Before submitting this PPRP FinalReport, the Panel had the opportunity to examine revised versions of Chapters 5-8 of the ProjectReport-the critical chapters describing the technical bases of the Updated EPRI (2004, 2006)GMM. A conference call was held with the TI Team and Project Manager to confirm that thePPRP's mandatory comments had been suitably resolved. Also, a member of the PPRP was onsite for one day to assist in final technical editing of these chapters as the Project Report wasbeing prepared for publication. It is on this basis that we affirm that the TI Team has adequatelyjustified, defended, and documented its technical assessments supporting the Updated GMM.

Updated GMM vis-i:-vis the CBR of TDI

Here, we revisit an assessment of this issue that we made in PPRP Report #5 regarding the TITeam's integration activity, i.e., how they evaluated existing data, models, methods and

LX

ultimately how their Updated GMM represents the CBR of TDI. To clarify the issue at hand:"The SSHAC process seeks to capture the center, the body, and the range on each component ofthe hazard study .... If the correlations between these component distributions are alsocaptured, this in turn will then result in capture of the center, the body, and the range of seismichazard estimates, which is the ultimate objective of the process" (NUREG-2117, section 3.1, p.33).

For clarification of terminology, we refer further to NUREG-2117:

Once a group of geological, seismological, and geotechnical experts have madetheir evaluations of all of the available data, the center of these interpretations canbe thought of as the best estimate or central value (median) of the distribution ofpossible outcomes as determined by that group. The term "body" can be thoughtof as the shape of the distribution of interpretations that lie around this bestestimate and capture the major portion of the mass of the distribution. The term"range" refers to the tails of this distribution and the limiting credible values.(NUREG-2117, section 3.1, p. 33)

Importantly, the excerpt from NUREG-2117 reproduced above points out how the center of TDIis achieved-in effect, it results from determinations of the TI Team. Whereas the body andrange of TDI can be compared to the available views of the larger technical community, thecenter of TDI is more fundamentally linked to the TI Team's informed judgment.

Based on our observation of the implementation of the SSHAC Level 2 process and our reviewof the technical bases and justifications provided by the TI Team in the Project Report, weconcur that the Updated EPRI (2004, 2006) GMM appropriately captures the CBR of TDI. Inparticular, we note the following:

The multi-stage engagement by the TI Team of resource and proponent experts from thelarger technical community gives us assurance that the TI Team's decisions to eliminatesome older ground motion prediction equations (GMPEs) and to substitute/include moreup-to-date GMPEs, which predict lower mean ground motions than the older GMPEs, arewell founded and not just reflections of the TI Team's own experience and opinions.

" Despite the great increase in available ground-motion recordings in the central andeastern U. S. (CEUS) since the development of the EPRI (2004, 2006) GMM, the TITeam's recognition of the limitations of these data for predicting future ground motionsin critical magnitude-distance ranges is an important element of the Updated GMM.Significantly, the TI Team has (1) abandoned an earlier decision to give greater weight todata consistency and (2) added a contribution to epistemic uncertainty that aims tocapture increased uncertainty due to the relative lack of empirical data and knowledge ofmagnitude scaling for earthquakes of magnitude 5 and greater in the CEUS.

" Ground motion data used to evaluate GMPEs are adjusted to take into account siteconditions of the recording stations. Uncertainties in the adjustments are incorporatedappropriately. The adjustments mitigate a known bias in the use of the ground motiondata to test GMPEs developed for a nominal site condition of 2800 m/s.

LXI

" The characterization of aleatory variability, updating the approach used for the existingEPRI GMM, is based on the published NGA-Westl models and preliminary results of theNGA-West2 project.

" The model updates the characterization of ground motion for the Gulf Coast region toincorporate current data and technical results, including NUREG-2115 4 and studies basedon data recorded by regional network stations of the Advanced National Seismic System(ANSS) and by EARTHSCOPE Transportable Array stations.

* Demonstration hazard calculations at the seven (7) test sites for both the existing EPRI(2004, 2006) GMM and the Updated GMM provide a level of assurance of consistency infinal results achieved, when compared to the existing model.

We are pleased to confirm that implementation of the GMM Review Project conformed with theSSHAC Guidance and that the resulting Updated GMM properly meets the SSHAC goal ofrepresenting the center, body, and range of technically-defensible interpretations.

This concludes our PPRP Final Report for the EPRI (2004, 2006) Ground Motion Model ReviewProject.

~¾Z~Walter J. Arabasz, Brian Chiou

Chairman

Richard C. Quittmeyer Robert B.Whorton

Copy: Gabriel R. Toro, TI Team Lead

4 Electric Power Research Institute, U.S. Department of Energy, and U.S. Nuclear Regulatory Commission(EPRI/DOE/NRC), 2012. Technical Report: Central and Eastern United States Seismic Source Characterizationfor Nuclear Facilities, NUREG-2115.

LXII

APPENDIX- ACRONYMS

ANSS

CBR

CEUS

EARTHSCOPE

EPRI

GMM

GMPE

NGA-East

NGA-Westl,

NGA-West2

NRC

NUREG

NUREG/CR

PPRP

SSHAC

TDI

TI Team

Advanced National Seismic System

Center, Body, and Range

Central and Eastern United States

An earth science program funded by theU.S. National Science Foundation

Electric Power Research Institute

Ground Motion Model

Ground Motion Prediction Equation

Research project to develop a new groundmotion characterization (Next-GenerationAttenuation) model for Central and EasternNorth America

NGA project(s) for Western North America

U.S. Nuclear Regulatory Commission

NRC Nuclear Regulation Report

NRC Nuclear Regulation Contractor's Report

Participatory Peer Review Panel

Senior Seismic Hazard Analysis Committee

Technically Defensible Interpretations

Technical Integration Team

LXIII

ABBREVIATIONS AND SYMBOLS

A08'

AB06'

AIC

ANSS

BA08'

BIC

CBR

CENA

CERI

CEUS

CFR

COL

COLA

DNFSB

DOE

ECC-GC

ENA

EPRI

EPRI-SOG

EQID

ERM-N

ERM-S

ESP

EUS

FEL

Atkinson (2008) GMPE with 2011 revisions (see GMPE below)

Atkinson and Boore (2006) GMPE with 2011 revisions

Akaike Information Criteria

U.S. Advanced National Seismic System

Boore and Atkinson (2008) GMPE with revisions of Atkinson and Boore (2011)

Bayesian Information Criteria

center, body, and range

Central and Eastern North America

Center for Earthquake Research and Information

Central and Eastern United States

Code of Federal Regulations

combined construction and operating license

Combined Operating License Application

Defense Nuclear Facilities Safety Board

U.S. Department of Energy

extended continental crust - Gulf Coast region seismotectonic zone

Eastern North America

Electric Power Research Institute

Electric Power Research Institute - Seismicity Owners Group

Earthquake identification number

Eastern rift margin - north

Eastern rift margin - south

Early Site Permit

Eastern United States

Frankel et al. (1996) GMPE

IXIV

FTP File Transfer Protocol

ft. foot or feet

ft/s feet per second

GC Gulf Coast

GHEX Gulf Coast Highly Extended Crust seismotectonic zone

GIS geographic information system

GMC ground-motion characterization

GMM ground-motion model

GMPE ground-motion-prediction equation

GMRS ground-motion response spectrum (or spectra)

GPS global positioning system

GV GEOVision, Inc.

HEM hybrid empirical method

HID hazard input document

Hz hertz

IRIS Incorporated Research Institutes for Seismology

IRVT inverse random vibration theory

ITC informed technical community

km kilometer(s)

K kappa: represents near-surface anelastic attenuation

LRSM Long-Range Seismic Measurements

m meter(s)

M moment magnitude

MALW multichannel analysis of Love waves

MSF magnitude scaling factor

MASW multichannel analysis of Rayleigh waves

mi. mile(s)

MIDC Midcontinent

MidC Midcontinent-Craton (seismotectonic zone)

Mmax maximum magnitude

m/s meter(s) per second

LXV

NGA Next Generation Attenuation

NMFS New Madrid fault source

NPP nuclear power plant(s)

NRC U.S. Nuclear Regulatory Commission

NTTF Near-Term Task Force

NUREG NRC Nuclear Regulation Report

*• intra-event component of aleatory variability standard deviation

PEER Pacific Earthquake Engineering Research Center

PGA peak ground acceleration

PGD peak ground displacement

PGV peak ground velocity

PM Project Manager

PPRP Participatory Peer Review Panel

PSA pseudo-spectral acceleration

PSHA probabilistic seismic hazard analysis

PZT Pezeshk et al. (2011) GMPE

Q Quality factor (used for quantifying anelastic attenuation)

QWL quarter-wavelength method

p mass density

R distance

RJB Joyner-Boore distance

RRup rupture distance

RFI request for information

RLME repeated large-magnitude earthquake

RR Reelfoot Rift seismotectonic zone

RR-RCG Reelfoot Rift - Rough Creek Graben seismotectonic zone

RSTN Regional Seismic Test Network

RVT random vibration theory

7- covariance matrix (also called variance matrix)

Ytotal aleatory variability standard deviation

SA spectral acceleration

LXVI

SASW spectral analysis of surface waves

SEL Somerville et al. (2001) GMPE

SDC Silva et al. (2002, 2003) double-corner GMPE (also denoted as DC)

SDCS Silva et al. (2002, 2003) double-comer with saturation GMPE (also denoted asDC-Sat)

SSCCS Silva et al. (2002, 2003) single-comer constant stress GMPE (also denoted asSC-CS)

SSCCSS Silva et al. (2002, 2003) single-comer constant stress with saturation GMPE (alsodenoted as SC-CS-Sat)

SSCVS Silva et al. (2002, 2003) single-comer variable stress GMPE (also denoted asSC-VS)

SSC seismic source characterization

SSHAC Senior Seismic Hazard Analysis Committee

Tinter-event component of aleatory variability standard deviation

TA EarthScope Transportable Array

TC technical community

TDI technically defensible interpretations

TEL Toro et al. (1997) GMPE

TIP Trial Implementation Project

TI Technical Integration (also Technical Integrator)

UHRS uniform hazard response spectra

USGS U.S. Geological Survey

UT The University of Texas

Vp compressional wave (P-wave) velocity

Vs, 13 shear-wave (S-wave) velocity

Vs30 time-averaged shear-wave velocity to a depth of 30 m

WNA Western North America

WUS Western United States

LXVII

epri (2004, 2006) ground-motion model (gmm) review projectepri (2004, 2006) ground-motion model...

Documents