Building an observatory pier

Was chatting to an Uncle about a pier earlier, knows little about astronomy but a lot about building.

He reckoned that reinforced concrete is the way to go. To have a 9" pier a meter above the ground, he reckons you would need to go almost as far underground.

Dig down, and create a wide base to stick the reinforcing bars into. Then buy a 9" diameter concrete pipe, put that in place, level it, support it with wood, and then pour concrete in, then sink in the mount base into that. Concrete should be mixed with one part sand and two parts gravel (or just gravel, I have some sand I'm trying to use up).

So now to find someone who can weld a mount base for me...

Cheers,
~Al