Almost 32 years ago, disaster struck the town of Chernobyl. Leaving it uninhabitable for any living thing for the next 20,000 years. But what happened at Chernobyl? Why did it happen? and is it safe to go there at all today? We’re going to be talking about all these in today’s article.
What Happened and why?
On 26th April 1986, testing was being carried out on reactor 4 to see how it copes with low power output. At 12:28 in the morning one of the operators made a mistake. Instead of keeping the power output at 30% he did not reset a controller which caused the power to drop to 1%.
At 12:54 in the morning, safety alarms sounded because of high void built up in the reactor but were switched off. Because of high void being built up, this meant that the reactor was not properly displaced. The steam amount was increased and the power was raised.
At 01:19 in the morning water flow to the reactor was increased to counteract the high void amounts and cool it down. Turbine 8 was shut down at 01:23 in the morning as scheduled. Because of this there was a huge increase of power.
At 01:23 in the morning, operators recognised an emergency and therefore shut down the reactor. All of the control rods were automatically lowered. All the control rods had 6 inch radioactive graphite ends. As they entered the core, a power surge occurred, which was 100 times more than normal operating level. The operators were not aware that the graphite would cause a temporary power increase. Each reactor was capable of producing 1000 MW of power.
The power surge lead to a massive increase of steam, therefor pipes began to burst, reactor core started to fracture and as a result an explosion occurred, lifting the 1000 tonne cover and flipping it on its side. Large amounts of steam, heat and radiation immediately started to escape into the atmosphere.
Another problem was found with the reactor which made the situation worse. As the fuel rods ignited, they started to melt, forcing their way through the concrete below which held a large water module. An operation began to drop sand and lead on top of the open reactor to try to smuggle the fire. Of course, there was a danger of the reactor being so hot, the sand would simply turn into lava and heat things up even more. This operation was carried out by men dropping the sand bags from helicopters.
If the molten fuel was to reach the water, it would create a geothermal explosion, ten times the size of an atomic bomb, levelling the ground up to a 200km radius. Unfortunately, the water module could not be remotely emptied. 2 volunteers were found and dived into the highly radioactive water to open up the flood gates. They never came back.
What was the aftermath?
The Chernobyl disaster released up 30,000 units of radiation per hour into the atmosphere. To give you an idea of how bad that is, 2 is the normal amount and 400 is enough to kill a person. During the disaster employees and firemen received more than 1,500 units of radiation per hour.
237 people suffered from acute radiation sickness. 31 died within the first 3 weeks. More than 135,000 evacuated from the danger area. Children were born deformed because of the accident and a red forest developed and is now the most contaminated area not just in Chernobyl, but in the world.
Is it safe to visit Chernobyl?
No. But it’s not impossible and there are tour groups that specialise in taking people on a two-day tour of Chernobyl. There are strict rules while on the tour and at no point should you wander away from your tour guide. The last thing you want is to be stranded alone in Chernobyl, miles from civilisation, with the chance of exposed to deadly amounts of radiation. I’ll leave a link at the bottom of this article, if you wish to find out more about Chernobyl tours.
A safe confinement structure over the Chernobyl sarcophagus and is the largest movable structure ever built.