12 inches of topsoil to bedrock need a GE

[Fred B]

Remote structure that will be getting a 4 wire; 2 hots, neutral, and ground. Needing the supplemental grounding electrode. Feeder is being installed in conduit and concrete encased because of crossing driveway. The installation is on bedrock and structure is on elephant foot peirs pinned to the bedrock no footers. Can I count the 100ft of encased re-rod as the electrode where crossing the driveway? Or, how do I get a grounding electrode in 12 inch or under to solid bedrock?

 

[zbang]

Does the concrete-encasement and rebar run all the way up to the remote building? That might count, but it's going to be an AHJ call.

 

[petersonra]

I think if you used rigid conduit it would count as an underground piping system that could be used as a grounding electrode perhaps. I would want to look at exactly what the rules are about such thing as though.

 

[Fred B]

Does the concrete-encasement and rebar run all the way up to the remote building? That might count, but it's going to be an AHJ call.

Yes all the way to the building. But not part of a footer of the building, there is no building footer only peirs. Perhaps he would have been better served if he had done a footer then there would be no debate over getting a GE at the remote building, but that is not what was done.