The highly dispersive nature of fluid-filled pipeline systems makes the use of traditional time-of-flight source location techniques generally ineffective. Because such methods rely on the assumption of a non-dispersive signal, they do not compensate for the multimodal characteristics of a real acoustic signal. This paper describes on-going work at ISU to understand the underlying principles of multi-mode propagation in fluid-filled pipes and to develop leak location signal processing which accounts for these propagation characteristics. Results which examine some of the practical problems to be encountered in the application of the previously-reported method, which uses both spatial and temporal transforms to isolate modes and determine source location, are reported. Data are presented that show the effect of transmission line interruptions. It is shown that the characteristics of a pipeline vary as a function of distance along the pipe, and that these characteristics can be determined empirically. Results indicating the effect of system background noise are also presented.