Since Iroquois' transmission pipelines are underground, line markers are used to indicate the approximate location of the pipeline. The markers display the material transported in the line, the name of the pipeline operator, and the telephone number where the operator can be reached in the event of an emergency. Markers only indicate the general location of a pipeline and cannot be relied upon to indicate the exact position. In agricultural areas, markers are generally not practical and may be found only at road and railway crossings, fencelines, and hedgerows.