Jeffrey Unruh
Senior Principal Geologist
– Structural geology
– Neotectonics
– Quaternary geology
– Seismotectonics
– Engineering geology
Dr. Unruh is President of Lettis Consultants International, Inc., and a California Certified Engineering Geologist with over 30 years of experience in neotectonics, structural geology, and seismic hazard evaluation. Jeff has conducted comprehensive multidisciplinary studies of seismic hazards for large, engineered structures such as dams, water delivery systems, nuclear power plants, and liquid natural gas facilities. Dr. Unruh currently is participating in a Senior Seismic Hazard Advisory Committee (SSHAC) level 3 probabilistic seismic hazard analysis for Idaho National Laboratory. For the past several years Dr. Unruh has been supporting the Department of Water Resource’s program to address the impacts of land subsidence on the California Aqueduct. He is currently leading a program to develop a probabilistic subsidence forecast model that will be used in a risk-informed feasibility study to evaluate alternative responses for restoring design capacity.
Key Projects:
– Oroville Emergency Response and Recovery, California Department of Water Resources (DWR)
– CA Aqueduct Subsidence Study, DWR
– Lower Columbia Dams Seismic Hazard Analysis, United States Army Corps of Engineers
– SSHAC Study to Update Seismic Hazard Model for Idaho National Lab, US Department of Energy
– Geophysical Investigation of the West Tracy Fault, DWR
– Geologic Investigations for the California WaterFix Project