Coal mines here have to run many hundreds of feet of large copper pipe to obtain 25 Ohms.
Tom could give you better actual numbers than me.
Alas, grounding is a major headache for me and I'm always interested in different methods...
Although not required to obtain 25 Ohms in the work I do (minimum 2 rods regardless by PoCo) I would like the rods I labor so hard to install actually do something!
Tell me more!
