That 70 ton number is too low for any superstrong guy. A M-1 U.S. Army tank weighs 70 tons. Those guys toss around tanks with ease. Ships get really gigantic when it comes to tonnage. If a super hero is tossing them around then he really is mega strong.
Well those numbers and those feats never quite match up. What number could you put that would explain how Hulk can hold up an entire mountain range or Hercules can tow the entire island of Manhattan?