You are 100% correct when you say "Just sitting a container on the ground increases the decomposition" I would block it like a mobile home and grade so water does not sit under it.Couple kids with an axe broke into mine when it was waiting on me to move it. The Corvette stored inside was a playtoy to them, judging by the amount of candle wax that was left. Glad i didn't lock the car, or leave the keys in it, as the results could have been worse!
Just sitting a container on the ground increases the decomposition of them, so burying it probably isn't a good idea.
David from jax