and melting down. the plant stayed unplugged for about an hour and a half while workers inspected the backup diesel pumps and then the regular pumps came back on. this thing with nuclear power plants staying on the grid matters a lot. in japan this year they first had an earthquake that caused a tsunami, but it was when the tsunami knocked out electricity at fukushima nuclear power plant that the world knew fukushima was really in trouble. without electricity fukushima could not keep its spent nuclear -- excuse me -- could not keep its reactors or its spent nuclear fuel cool. the japanese government now says that three of the reactors may have suffered not just meltdowns, but melt-throughs. melt through the internal super strong containment vessel. that is a real nuclear nightmare. wucht things we are learning as this scary situation drag on in nebraska is that fort calhoun, ç which was built in 1973, fort calhoun was built partly on the basis of a mistake. somebody miscalculated the pumping capacity the plant would need for a cat strafk flood.