Jim Lux wrote:

The minimum depth is provided by the building code. Since the footer
must be below the frost line the resultant Ufer Ground is also below
the frost line. If it's not it will be ineffective.


To split hairs a bit, you can build a Ufer ground that isn't a
structural footer, and so, may not be subject to the frost line rules.


Yes Jim he can. But if he does will frost heaves likely destroy it.
When I was younger I spent a lot of time building duct banks and they
were always built with the base of the bank below the frost line so that
the formation of ice in the soil during a hard winter would not destroy
them. Remember that even a ground ring composed of straight wire is
buried a minimum of thirty inches deep. The objective in constructing
grounding electrodes is to get them down below the permanent moisture
level well into the so called water table.

I know that the subject area is Texas and the strata he's dealing with
is quite hard but he didn't seem to be asking how to install what looks
like an electrode but rather what will function as an electrode.
--
Tom Horne

"This alternating current stuff is just a fad. It is much too dangerous
for general use." Thomas Alva Edison