The mechanisms of electromagnetic interference between a power line and a neighboring pipeline using electromagnetic fieM theory are discussed based on a simple right-of-way scenario. First, the field theory approach is used to model the complete conductor network under consideration, as is. The inductive, capacitive and conductive interference
effects between all the elements in the network are simultaneously taken into account in one single step. The computed results are then used to develop new computer models whereby the effects of the inductive, capacitive and conductive interference effects can be separated. This allows us to compare the field-theory-based results with the results obtained from other approximated approaches, such as grounding analysis (conductive effects) and circuit-based models (inductive effects). The effects of a typical mitigation system on the interference levels are also studied. The results presented in this paper clearly illustrate the mechanisms of electromagnetic interference between electrical networks and neighboring metallic utilities. Furthermore, the methods used here should help develop more accurate approximations when modeling non parallel pipelines using conventional circuit theory.