This was my thought also, although it may not be trivial to just hire an oil tanker to transport radioactive water. Before dilution, there may be a significant

This was my thought also, although it may not be trivial to just hire an oil tanker to transport radioactive water. Before dilution, there may be a significant risk of contamination to the vessel and crew. You'd probably need a special vessel, specifically designed to handle radioactive fluids. Even if an oil tanker is technically adequate, there's likely some costly certification / approval that would need to be done. All the handling involved would also introduce risks, and is probably more cheaply and safely achieved on land. That said, there's a political aspect to this, and maybe the perception of disposing of the water far away from Fukushima justifies the scientifically unnecessary added complexity.