Brief 4 - Message Delivery: The Chernobyl Disaster

The spread of radiation from Chernobyl 

The Chernobyl disaster happened in April 1986, It was the worlds worse nuclear accident when reactor 4 exploded. The reason this is so key to the research into Hinkley point because it made people question the very idea of nuclear power. It brought death and birth defects for years to come.

There was a fatal floor in the reactors design where it becomes highly unstable whilst running at low power. The owner and man in charge wanted to dominate over the technology. On the night of the disaster they were supposed to be running a test on the safety after a few years before they were bombed by Israelis, because of this soviet scientists demand tests to check how they would cope with out the power. However the man who was in charge didn't follow the guide lines and did not run the test properly. There was instructions to run the reactor between 700-100 megawatts when the test began but he ran it at 200megawatts to preserve the cooling water from over heating. He didn't listen to anyones opinion of the workers below him. 

The water drums levels were low so the low power stalled and grounded to a halt, and the foolish decision to pull the control rods to start power up again was made. The control rods are the break and the accelerator of the nuclear reactor, so doing this was described like cooking a gun. There are over 1000 uranium filled fuel rods the splitting of uranium atoms realises heat from the fuel rods, this produces a mass of steam from the water. This steam then turns a turbine and generates electricity. To control this 211 control rods are spread through the core, if they are raised the power accelerates and if they are taken out altogether they loose the ability to apply the breaks. This is what happened.  They believed the chances of the accident were completely rare, even those who are aware of risks and danger estimated that there was only a 1 in a million chance of an accident.

KGB Documents came out which showed the plant had ignored serious warnings about the design floors of Chernobyl between 1979 - 1986. The director and senior mangers rushed to open the reactor number 4 early so they could win bonuses, for them the safety came second. For example the roof was meant to be made from non flammable, fire proof materials but they didn't feel they had time so they used combustable material. Accidents were constantly covered up and swept under the rug so to speak. Interestingly the test that they were running on the night was meant to have been ran before the reactor was even opened and operational.

Power built up at the bottom of the core which formed hotspots where a few of the control rods had been left partially in at the top. These lower parts would not show up on the system so the plant became a ticking time bomb. As previously mentioned the water levels were low, the alarms for this were ignored. This meant that is was boiling like an empty kettle. More and more energy began to be produced with less and less water. The steam pressure from the core managed to lift the 350 kilo caps to the fuel rods out of their sockets!

Reading into the disaster and also watching documentaries on it, it has become clear that living in the soviet country played a part in why the workers didn't speak up more often. It is reported that quite a few did say that the station wasn't following procedures but even they were fully aware of the risks. One of the points that was highlighted was that the workers for the plant had been provided with accommodation near to the plant together and schools were built for their children along with other benefits. They were given a very comfortable life style so rising up over an accident that they thought was unlikely to happen didn't seem worth it.