We did this for anode placement. You put a anode x hundred yards away from a pipeline to stop it rusting. We used to send people into the field with metal spik

We did this for anode placement. You put a anode x hundred yards away from a pipeline to stop it rusting. We used to send people into the field with metal spikes to measure conductivity to find the best locations. You want the anode in a place of high conductivity. This was used instead. Personally I was dubious on the economics of a few of the things that was done on the project, doing this compared to using people was a no brainer even if it was $$$$. But all this money and as usual the SCADA was crap. The rig was from mining if you wonder about it's everyday use.