On Saturday 26th April 1986, Ukraine experienced the biggest disaster in its history.
In unit 4 of the nuclear power station at Chernobyl, staff were testing whether the turbines that powered the conductors could produce enough energy to keep the cooling pumps running before the emergency generator kicked in, in the event of a power loss. For this, the safety systems were switched off.
Though the reactor was due to be turned down to 25 per cent of its capacity, the reactors fell instead to below one per cent. In light of this, the power had to be turned back up in a controlled manner. Unfortunately there was a sudden power surge and the emergency shutdown failed, causing the disaster.
The result was a catastrophic explosion. With temperatures over 2,000 degrees celsius, the one thousand tonne sealing cap on the reactor blew off, causing the graphite covering of the reactor to also ignite – causing an inferno that raged for nine days, releasing over 200 times the amount of radiation of Hiroshima.
In the following days, 2,400 tonnes of lead and 1,800 tonnes of sand were dropped over the site to try and calm the fire; however, this approach only increased the heat. It was not until 6 May that the blaze was put under control and by that time the disaster had already taken its toll.
Seven million people have since been affected, 30 losing their lives to immediate exposure to radiation and since then at least 25,000 ‘liquidators’ (the term for those involved in the clear-up) are estimated to have died due to the exposure. There have been approximately 700,000 liquidators since that time and those who survive continue to be blighted by health complications today. Indeed, the heightened risk of cancer in the area is not expected to improve for the next 40 years.
However, perhaps what is most worrying about Chernobyl is that to contain the disaster a concrete ‘sarcophagus’ was constructed on the site, to prevent any further radiation damage. But, due to the fact that this was designed to last 20 to 30 years and the fact that it has been in place now for 32, it is feared that the next Chernobyl-level disaster will be Chernobyl itself.
Image: Wikimedia Commons