I remember the Chernobyl reactor disaster occurring when I was at school. The news was full of talk about radioactive Welsh milk and general fretting about contamination everywhere. I don't remember a lot of "hard" information, though. Of course, in these post–Perestroika and internet–enabled days, information is plentiful. I read up about the disaster, and looked at the event from various angles.
The technical issues are of great interest to me, of course. As is so common with such things, the problem was part technical, and part human. The operators were experimenting with new safety procedures, and were unaware that operating the reactor at very low power levels was hazardous. The explosion itself was not nuclear. The tremendous heat generated just prior to the explosion turned some of the cooling water to steam very rapidly. This dramatically increased the pressure inside the reactor vessel, forcing the lid free of the rest of the reactor and throwing highly radioactive debris into the air.
The nuclear reaction continued, beyond all human control. The resulting fire produced clouds of radioactive dust. This spread over the entire planet, though of course the level of contamination dropped rapidly as the distance from the reactor increased. Kiev was saved only because the wind blew the dust northwards. The neighbouring country of Belorussia was not so lucky. If you are interested, have a look at Elena Filatova's Site, which contains a good deal of information.
Of course this disaster affected a great many lives, and tens of thousands of people were seriously affected – though loss of life, homes etc. How quickly mankind's toys can turn to bite him.
I hadn't imagined that I would ever actually visit the site. While visiting Kiev recently, the opportunity arose. This is me standing in front of the wreckage of reactor no. 4, the source of all of the trouble. Yes, it is still rather radioactive here, and I and the rest of the group didn't linger.
The nearby town of Pripyat was built to house the workers at the reactor site and their families. Being so close to the reactor, it was heavily contaminated and therefore had to be evacuated. This meant thousands of people leaving almost everything behind. Originally, it was felt that they would soon be able to return. However, it turned out that this was not possible, even after considerable decontamination efforts. This picture shows the hotel.
Pripyat is an odd place. Our guide said he disliked being there at or after sunset. While looking around this abandoned town, I tried to imagine what it must be like to have considered this home, then to have left, leaving everything behind, never to return. We really don't have much to complain about. Remind me of that next time I grumble about the rain.