Or we could pick a) an uninhabited Island or b) not have it on land, have it floating. Or c) have it flying. A 10km * 10km * 1km bag of Hydrogen or Helium can carry 80,000,000 mt at sea level. Admittadly it would have to use H2 as we don't have enough Helium, which is a bit of a fire risk, but if my idea bears fruit it would be able to lift 125 million tons with no fire risk.
Craazy idea, but it'll happen.