I'm assuming that's what this is...

My father-in-law's house had a solar system installed in the mid-70s,
which never worked properly. The panels are long gone, but the plumbing
and storage tank remain. As far as I can tell the system had a double
tank, with the inner tank being house water and the outer tank being
part of the solar circuit. The tank is uninsulated steel and thus has
pretty much no value. We'd like to get rid of the tank because it's
taking up a large amount of needed space.

I was able to drain the water from the inner tank into the ground by
hooking a hose to it and running it to a corner of the basement which
was left open for sewer drain access; however, the solar circulation
loop apparently is filled with some sort of (clear) anti-freeze. I have
no idea how much there is. What's the easiest way to get rid of this
stuff? I'm assuming just dumping it into the ground or the sewer system
would be a Bad Thing.

The house is located on Long Island, if that information is meaningful.

Please post to the groups; this email address is dead.

Thanks,

Steve