Nice, they should have built these right after Three Miles Island and Chernobyl ...
Sakura's mission is to go into the underground levels of nuclear power plants. It's very compact, as it has to go down stairways just 70 cm wide, and turn around on landings that are also 70 cm."
"Coolant water is leaking from somewhere inside the reactor, because no matter how water much is pumped in, the level doesn't stay above 60 cm. But unless that space can be filled with water, the melted-down fuel rods can't be removed safely. So, Sakura's first job is to find out where the cracks are."
"The part above ground slopes at 40 degrees, and that below ground at 42 degrees. This difference of just two degrees is very hard for a robot to handle. What's more, Sakura has to climb down, and then climb up, to the top of the suppression pool. That stairway slopes at 53 degrees."