Ed_G wrote:

Thanks, Dave. That is probably what I may do, I don't want to be
putting in overkill for my situation ( that would be rods every 8 feet
all around the house and connected by #0 copper! ). I'm more interested
in grounding for electrical safety than lightning protection. I'll
probably just put in two or three standard 8' rods and connect them with
large copper cable. My question was aimed more at wondering how
effective for this purpose a ground rod or three would be in sand......

And thanks to those who mentioned the rebar grid... but this house is
on pillars, with rebar only in the perimeter foundation.... and well
embedded in the center of the concrete, at that, so as to preclude any
access.

For an electrical safety ground, you should follow the requirements of
the National Electrical Code (NEC).

Roy Lewallen, W7EL