The location, location and mapping of hidden facilities make it possible to avoid the risks of accidents and other nuisances that can cause material and human damage during the various phases of planning and construction of a project. Hence it is important to identify these to solve several problems on a given site. Damaging these buried utilities during construction work, urbanization continues to be one of the major risks for different industries. Currently, it is important to update information on hidden utilities that will serve several scientific disciplines during field work and for successful projects involving excavation, well drilling, exploration drilling, leveling And construction in the field of civil engineering. Bluestake (picketing and marking) processes identify and locate the various hidden utilities such as underground piping, ducting and cable systems, sewers and other installations that can emit a frequency that can be detected during field prospecting . Accordingly, the Blue stake processes are based on the geophysical prospecting method, see the electromagnetic approach using an apparatus consisting of a transmitter, a receiver, electrodes, the ground rod and the electromagnetic field clamp which Of the searched utility sends a detectable frequency and then locates it for mapping.