Well, it wasn't just heated water but a radiation "leak". That could explain the temperature but not why people are still alive, I suppose.
I can remember when there was the Chernobyl disaster, I was way out in the country side (not even in Russia) and I ended up with sun burns.
*scratches head*
It was believable to me though, since they didn't really explain the circumstances of the "problem". I guess there could be instances where it could be done.