[R-390] Underground connection sealant/insulation

[Dan Merz]

Hi,  I'm now dealing with putting in some ground points at various locations
for my 390 receiving antenna system and am looking at using some type of
sealant/insulation over a few connections that will be in the dirt or within
the concrete of the footings.  I want to cover the connectors with something
that will for the most part prolong the connections,  which are mechanical,
clamped connections between copper wire and iron rebar/galvanized hog wire.
I can't get these connections above grade which would make the connection
more reliable.  I'm trying to bury the grounding rather than driving a rod
into the ground.  I picked up some GE Silcone II "Blacktop and Roof, black"
stuff in a caulking container at the local hardware and read a little about
RTV/silicone materials online and decided the stuff I got was the more
desirable alcolol curing type and not the not-for-electronic use  acetic
acid curing,  vinegary smelling type.  It there a hardware variety type that
might be better than this or something that is commonly used for such
connections?  My first idea was to find some asphalt base material since I
know asphalt has great longevity and there was one caulking material that
was asphalt base but I opted for the Silicone II figuring it might cure
faster and endure as well.  Any thoughts appreciated,  Dan.