Dr. Timothy Stark is a Professor of Civil and Environmental Engineering at the University of Illinois at Urbana-Champaign. Dr. Stark has been conducting interdisciplinary research on geosynthetics, and in particular geomembranes, for the last twenty-five (25) years. This includes his research on the installation and long-term durability of geomembranes and other geosynthetics in geo-environmental and the static and seismic stability of landfill liner and cover systems. His research on the static and seismic stability has led to a better understanding of design geosynthetic interface strengths, the importance of interim slope conditions in landfill operations, and the shear behavior of various geosynthetic interfaces. He is also the Technical Director of the Fabricated Geomembrane Institute (FGI), which is an industry sponsored research organization investigating the advantages and disadvantages of geosynthetics for containment applications.