Expertise: Mr. Eloy U. Retamal, S.E., is a registered structural engineer in California and Chile, two of the most active seismic areas in the world. Mr. Retamal is a pioneer in the use of performance based specifications for the procurement of seismic isolators and has been involved in projects since the late 1980’s, when use of the technology became more widespread. He has had multiple articles published on the topic of seismic isolation and has presented on the topic worldwide. He has specialized in earthquake-resistant analysis and design of structures in structural steel, reinforced concrete, reinforced masonry and timber. His experience centers on response spectrum, non-linear time-history, non-linear finite elements analysis, and evaluation of energy absorption systems utilizing base isolation and/or passive damping devices. Mr. Retamal possesses unique experience in the long-term recovery efforts in the wake an earthquake, having served as the lead structural engineer and program director for the recovery from the largest disaster in the history of the United States for an American University: California State University, Northridge (CSUN). The 6.7 magnitude earthquake devastated the campus by breaking power and water lines and damaging all 107 buildings on the campus and required a billion dollars (in today’s dollars) in government aid to restore the university.