1 central coastal california seismic imaging project california energy commission workshop dr....

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Central Coastal CaliforniaSeismic Imaging ProjectCalifornia Energy Commission Workshop

Dr. Stuart NishenkoPG&E

April 27, 2015

Overview

PG&E Long Term Seismic Program• Continually assesses seismic safety at Diablo

Canyon Power Plant (DCPP)• Advanced seismic research (conducted 2010-2013)

has provided a more detailed picture of the region’s complex geology

• Studies published in 2014 provide an unprecedented look into the Earth around DCPP and further defines the level of seismic activity that the earthquake faults are capable of producing

Overview

Research confirms previous analyses:• The plant is designed to withstand the ground

motions, or shaking, from earthquakes• Major components can continue to perform their

safety functions during and after a major seismic event

History of Assembly Bill 1632

In 2006:

California Assembly Bill 1632 requires the California Energy Commission (CEC) carry out:

“…a compilation and assessment of existing scientific studies…to determine the potential vulnerability to a major disruption due to aging or a major seismic event of large base load generation facilities of 1,700 megawatts or greater.”

History of Assembly Bill 1632

In 2008:

California Energy Commission (CEC) issues an Assessment of California’s Nuclear Power Plants: AB 1632 Report

- Recommends PG&E update seismic hazard assessments;

- Directs the use of 3D geophysical seismic reflection mapping and other advanced techniques to supplement previous and ongoing research programs

History of Assembly Bill 1632

From 2010 – 2015:

In response to the CEC recommendations, the California Public Utilities Commission (CPUC) directs PG&E to complete the 3D seismic studies and convenes an Independent Peer Review Panel (IPRP) to review, evaluate and report on PG&E’s study plans and resultsIPRP membership :

- California Coastal Commission- California Emergency Management Agency - California Energy Commission- California Geological Survey- California Public Utility Commission- California Seismic Safety Commission - San Luis Obispo County

PG&E/PUC/IPRP Coordination2010 - 2015

18 Public and Information Meetings

9 IPRP Reports + Evaluation Poster

Before and After: Comparison of Hazard Significant Parameters

Sensitivity Hazard / 10-4 @ 2 gSensitivity Hazard / 10-4 @ 2 g

Improvements in Geophysical Data Acquisition

- Geophysical Instrumentation

- Geophysical Data Processing

- DGPS Navigation

- Geographic Information Systems

- 3D v 2D Seismic Imaging

- X-Rays vs CT scans

- Revolution in Spatial Resolution

1. Multi Beam Echo Sounder & Potential Field Mapping*

2. 2D/3D Low Energy Seismic Surveys (LESS) - Shoreline Fault Zone

3. 2D/3D Onshore Seismic Reflection Surveys - Irish Hills/Los Osos Valley

*Long Term Seismic Program

Central Coastal California Seismic Imaging Project 2009 - 2011

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1. 3D LESS – Southern Shoreline Fault Zone

2a. 3D LESS – Hosgri Fault Zone, Point Sal

2b. 3D LESS – Hosgri Fault Zone, Estero Bay

3. 2D/3D Onshore Survey, Western Irish Hills/ DCPP

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2b3

2a

Central Coastal California Seismic Imaging Project 2012

Multi Beam Echo Sounding

Marine Geophysical Surveys

Mapping the Sea Floor – Multi Beam Echo Sounding

San Luis Obispo Bay 3D Survey

3D View of San Luis Obispo Bay

2012 Data Collection Area

2011 Data Collection Area

Shoreline Fault Offset San Luis Obispo Bay

Hosgri Channel OffsetsOffshore Point Sal

VibroSeis in Irish Hills

Accelerated Weight Drop

2D/3D Land Seismic Reflection Surveys DCPP/ Irish Hills/ Los Osos Valley

EnviroVibe at DCPP

Irish Hills 2011 2D/3D Seismic Acquisition Geometry

Central Coastal California Seismic Imaging Summary

Central Coastal California Seismic Imaging Summary

Point Buchon Ocean Bottom Seismometer Project

Central Coastal CA Seismic Imaging Report

pge.com/en/safety/systemworks/dcpp/seismicsafety/report.pge

2010-2012 Marine Seismic Reflection Data

https://walrus.wr.usgs.gov/NAMSS/surveys/survey/469/

2011-2012 Land Seismic Reflection Data

http://www.iris.edu/hq/http://ds.iris.edu/data/reports/2014/14-027/

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Thank You

Dr. Stuart NishenkoSPN3@pge.com