My 24 hour fan aspirated ISS is going to be attached to a Galvanized pole about 6 feet from the ground. I'm too far down the road to think about something else for support.
Well, Dr. Bob - is the ISS going to be 6 feet above the ground? Or the anemometer? Or how tall is the pole, and what is nearby? Perhaps, if you gave more information, people could give better answers.
But:
Sod would make it look nicer.
What size holes would you have to put in the pipe, to run the anemometer cable through them?
And, are you going to put a cap on the top of the pipe, to prevent rain from getting in? Or how does it get out? In other words - try being longer on descriptions.