[TowerTalk] Grounding a tower in sand stone

[Jim Lux]

On 7/15/15 10:20 AM, Kent Olsen wrote:
> I have my tower up. The next thing I want to do is grounding.
>
> While digging for the foundation of my tower I hit sand stone and about 2
> 1/2 feet. We broke a back hoe digging through the sand stone.

Your concrete base, with all of its rebar, will be a suitable ground, 
and much better than any rod you drive.  The contact area of rebar with 
concrete is huge, and the concrete to soil contact area is huge-er.

>
> I would like to pound a 8 foot ground rod in but I do not think I will be
> able to do it it all the way in. I have seen some people say you can pound
> them in at an angel. Is this ok?? Is it not as well grounded if this is
> done??

Sure, you can lay it horizontal in a trench, too.

But I'd just make a Ufer ground (concrete encased grounding electrode) 
in your concrete base.  Make life easy and put 20 feet of bare 4 AWG 
copper wire in the concrete and bring it up through the top to connect 
to. Actually, if you've got bolts in the concrete, they'd make a 
connnection too, but it's nice having a copper wire to connect with.

25 feet of bare AWG4 was just under $40 a couple weeks ago when I bought it.