Comment by dmurray

It doesn't really matter. 45,000 acres for a tank farm, or multiple tank farms, would be basically free by the standards of this project. Yes it's "an area the size of Washington DC" but it wouldn't be in Washington DC, where rent is expensive, it would be on some low-value desert land that the military might otherwise use as an artillery range.

Storing it in underground salt caverns is more secure, not necessarily cheaper.