UFER electrode question

[Robert Olin]

I'm using the rebar in my storage shed/well house as the grounding
electrode. I just read that the footing has to be in contact with the
earth, which means that I'll have to pull back the plastic that I have
extending across the footing. Question:
Is it sufficient to pull back say 25 feet of plastic(the UFER has to be 20'
long (it will be the entire perimiter rebar), or should the entire footing
be on the dirt?

Thanks,
Bob
--
Robert Olin
Bob's Water & Septic LLC
jo...@whidbey.net
http://soilsandseptic.com/bobs.html

[John Grabowski]

> I'm using the rebar in my storage shed/well house as the grounding
> electrode. I just read that the footing has to be in contact with the
> earth, which means that I'll have to pull back the plastic that I have
> extending across the footing. Question:
> Is it sufficient to pull back say 25 feet of plastic(the UFER has to be
> 20' long (it will be the entire perimiter rebar), or should the entire
> footing be on the dirt?

*Soil conditions vary by region which affects the ground resistance
therefore the more contact the better. However I just read 250.52(A)(3) and
the way I interpret it you are fine with 20'. Your best bet is to contact
your electrical inspector and ask him.

In addition to the above you could also take two ground rods and lay them in
the trench along side of the footings as long as they are at least 30" deep
and at least six foot apart. 250.53(B) and 250.53(G)