Subway tunnel condition assessment presents significant challenges for engineers, and is becoming increasingly important as the systems continue to age. Technologies are needed that can rapidly and accurately assess the condition of subway tunnels, and identify distress such as delamination, moisture-related damage, without interfering with the normal operation of the system. Towards this goal, different nondestructive evaluation methods including SASW, Impact Echo, GPR, and Impulse Response were evaluated to determine their advantages and limitations for tunnel evaluation. Since tunnels are in constant heavy use in an aggressive environment, it is necessary to distinguish between methods that can be used for high speed screening, and those that require interruption of subway traffic. It is also necessary to develop automated procedures to process the vast amounts of data generated during extensive NDE testing. Introduction and Problem Statement There is an increasing need for better methods to evaluate the integrity of transit infrastructure. Some transit infrastructure, particularly rail transit tunnels and underground structures, is over 100 years old. While the risk of collapse may be remote, there is a possibility of injury to the public and/or significant service interruption caused by falling concrete, loose reinforcing bars, and leakage. Traditional destructive techniques, such as coring, and currently used non-destructive techniques, such as hammer sounding, are time consuming, cover limited area, and have limited effectiveness in identifying possible sites of deterioration. 1 Department of Civil and Environmental Engineering, The University of Alabama at Birmingham, 1075 13 ~ Street South, Suite 120, Birmingham, Alabama 35294-4440 2 Department of Civil Engineering, School of Engineering, The City College of New York NYC 100M 3 Civil Engineering Department, Cleveland State University, Cleveland, Ohio 44115-2440 4 412 S. Peoria, Suite 340, Urban Transportation Center (MC 357), University of Illinois at Chicago 5 Department of Civil & Environmental Engineering, Rhodes 730, PO Box 210071, Cincinnati, OH 45221-0071