Topband: Edger for burying ground radials ?

[Kenneth Silverman]

I haven't used one, but what about renting a wire/cable trencher from your
local equipment rental store?

Here's a video of one type
http://video.google.com/videoplay?docid=3967613380941633039#  though this
type sure makes a mess.  I've seen some that use a blade and aren't as
messy, and I've seen pictures of a blade type that attach to the back of a
tractor.

You might search under dog fence trencher.

Kenny K2KW