[Lowfer] LF interference - slightly off topic...

[JD]

Perhaps they are to electrify particular locations where they don't want 
dogs peeing? :-)

But seriously, I don't know.  My first thought was monitoring of ground 
currents for possible seismic connections, but you'd hardly need such an 
array at each individual monitoring point.  Could be the sort of thing you'd 
use to track leakage from buried electrical power lines, but I can't imagine 
why they'd need miles and miles of them.

Do they actually seem related to the LF source you were hunting down, 
Laurence?

John