by Jonathon Mayo for the Daily Mail
The V.I. Lenin Nuclear Power Station at Chernobyl, with its four RBMK nuclear reactors, was the pride of the Soviet Union, generating electricity for 30 million homes and businesses.
It was an operating system the West had rejected because of concerns about design flaws and its safety, but the Soviets were confident it was secure. In an interview in February 1986, Vitali Sklyarov, the Minister of Power and Electrification of the Ukraine, said: ‘The odds of a meltdown are one in 10,000 years.’
JONATHAN MAYO reveals, in gripping detail, how the catastrophe unfolded minute by minute…
Sky series, Chernobyl, shed new light on one of the world’s worst nuclear incidents
Friday, April 25, 1986
It has been an unseasonably warm day at Chernobyl, in northern Soviet Ukraine, and the cherry trees are already in bloom. In the shadow of the power station, scores of fishermen are settling on the edge of a large artificial pond — its waters are used to cool the plant’s four giant reactors. Power station bosses boast that the water is so safe they are breeding fish there. Angling is prohibited but the fishermen know that at this time of night no one will bother them.
Anatoly Dyatlov, Chernobyl’s 55-year-old deputy chief engineer, arrives at work. Tonight he will be overseeing a test authorised by the Soviet Energy Authority to assess the plant’s ability to keep its latest reactor, No 4, cool in the event of a power cut.
The test should have been carried out before the reactor became operational in 1984, so it is two years overdue.
The son of a Siberian peasant, Dyatlov has risen to become the leading nuclear expert at Chernobyl. He is an intolerant manager and keeps a notebook to write down the names of those who cross him.
engineer Sasha Yuvchenko, 24, clocks on for the night shift. The tall young man is one of 176 workers at the power station tonight. He changes into regulation white overalls and cap and makes his way to his office, between Reactors No 3 and No 4, to be briefed by the engineer he is taking over from.
A former champion rower, he has just said goodbye to his wife Natasha and their two year-old son Kirill in the nearby city of Pripyat, built from scratch in 1970 to house the thousands of workers at the plant. It now has a population of just under 50,000.
The nuclear industry is prestigious and Pripyat’s supermarkets are better stocked than most in the Soviet Union. It has good schools and sports facilities.
It was an operating system the West had rejected because of concerns about design flaws and its safety, but the Soviets were confident it was secure (pictured: Chernobyl)
Saturday, April 26, 1986
The large control room of Reactor No 4 is harshly lit by fluorescent lights and full of cigarette smoke. The atmosphere is tense. No one has done a shutdown test like this before.
Anatoly Dyatlov is arguing with the shift foreman, Alexander Akimov, about the level of power produced by the reactor at which it is safe to begin the test. The lower the power, the more danger there is of an accidental shutdown.
The rule book, which Akimov has in his hands, stipulates that it should be no less than 700 megawatts, otherwise the reactor will become unstable. Dyatlov insists that 200 megawatts is safe. Akimov is outranked by Dyatlov, so he reluctantly agrees to allow the test to continue.
The reactor control engineer, 26-year-old Leonid Toptunov, who has only been in his job a few months, switches the system from manual to automatic. But he misses a vital step, failing to select a megawatt level at which the control room computer would then operate.
The computer defaults to the last level that had been inputted — near zero. Power in Reactor No 4 falls almost to zero megawatts. The reactor is now unstable and has the potential to explode.
Alarms begin to sound. Alexander Akimov says that the rulebook states the test should now be aborted. But Dyatlov wants it completed and insists they continue. That the reactor might explode is unthinkable to him.
In the reactor’s core are more than 1,600 radioactive uranium-235 metal fuel rods. Uranium-235 is unstable, its atoms constantly breaking down to release subatomic particles called neutrons — which hit more uranium atoms, so triggering a chain reaction that generates enormous heat and energy.
In a controlled chain reaction, this heat can be used to turn water into steam that powers a turbine to generate electricity.
Control of the reaction depends on 211 boron control rods spread throughout the reactor’s core. They can absorb neutrons and so slow the chain reaction.
If the rods are raised, the chain reaction accelerates. If they are taken out altogether, the engineers lose their ability to stop the reactor overheating.
In an attempt to lift the power level, Dyatlov orders the control rods to be raised. Alarmed by the likely loss of control, Toptunov refuses to do so.
Threatened with the sack by Dyatlov, Toptunov finally agrees to raise the control rods and the reactor is powered up to what is regarded as a safer 200 megawatts. But it is increasingly unstable.
The control room computer is demanding that the reactor be shut down, but the test is scheduled to begin. Alexander Akimov hesitates over the controls. ‘What are you waiting for?’ Dyatlov says impatiently.
In an interview in February 1986, Vitali Sklyarov, the Minister of Power and Electrification of the Ukraine, said: ‘The odds of a meltdown are one in 10,000 years’ (pictured: Chernobyl TV miniseries)
1.23 and 40 seconds
The temperature in the reactor is now 4,650c — almost as hot as the surface of the Sun. Akimov presses the button to start the test, inadvertently starting a catastrophic chain reaction that generates enormous amounts of steam.
Suddenly, Valeri Perevozchenko, an engineer who had been on a catwalk high above the reactor, bursts into the control room in a panic, shouting that he has seen the 350kg (772lb) caps on the fuel rods jumping up and down in their sockets. Then the control room walls start shaking and the men hear a sound like a long, low human moan — followed by a huge explosion as a build-up of steam blasts the 200-ton concrete shield above the reactor into the air.
In the control room, Akimov shouts: ‘Shut down the reactor!’ But it is too late.
1.23 and 45 seconds
There is a second, much louder blast as 50 tons of radioactive uranium fuel from the reactor core — ten times the amount at Hiroshima — vaporises and is blasted into the atmosphere. Uranium-235 has a half-life (the time it takes for the radioactivity to fall to half its original value) of 700 million years.
A further 70 tons of uranium and 900 tons of radioactive graphite is scattered around the surrounding area, including on Reactor No 3.
In No 4’s reactor core, 800 tons of graphite start to burn, sending more lethal radioactive material 3,000 ft into the night sky. The men fishing by the cooling pond are illuminated by the flames.
In the control room, dust and debris are falling from the ceiling and the terrified technicians think they are in the middle of an earthquake. No one imagines it could possibly be the reactor.
More alarms sound, the fluorescent lights go off and the emergency generators kick in.
Sasha Yuvchenko is in the senior engineer room, talking to a colleague who has come to collect a tin of paint, when a shockwave hits the room. ‘The metre-thick concrete walls were bent like rubber. I thought war with the Americans had begun,’ he later said.
Jessie Buckley plays Lyudmilla Ignatenko, the young wife of Vasily, a firefighter who suffers from exposure to radiation at Chernobyl
Everywhere there is an ominous hissing noise. Yuvchenko runs from the room and, behind a pile of rubble, finds a badly scalded and bloody pump operator, who tells him he must rescue their colleague Valery Khodemchuk, who is in the main circulating pump room close to the explosion. ‘He’s still trapped in there!’
Outside Paramilitary Fire Station Number Two, 500 yards away, firemen enjoying the cool night air watch in horror as a giant mushroom cloud of smoke rises from the power station. In their operations room, hundreds of red lights are flashing — one for every room in the power plant.
The crews run to their trucks. In charge is youthful but respected 23-year-old Lieutenant Vladimir Pravik. On his radio, he summons every fire crew in the region.
At his home in Pripyat, Viktor Bryukhanov, the director of the Chernobyl plant, is woken by a phone call. His wife watches as the colour drains from his face. Bryukhanov gets dressed and leaves without saying a word.
Sasha Yuvchenko is still searching for Valery Khodemchuk in the reactor building. He looks up and sees stars — the ceiling has disappeared.
Sparks are showering from severed power cables and a blue-white beam of radiation from the core is shooting upwards.
‘I remember thinking how beautiful it was,’ Yuvchenko said afterwards. There is no sign of Khodemchuk.
The control room of Reactor No 4 is filled with dust. A shocked Dyatlov is trying to understand what has happened. Unaware that the reactor is a blazing volcano, he hopes water might save it from damage and orders Akimov to activate the emergency cooling pumps. ‘We’ve got to get water into the reactor!’
On A ledge more than 100ft up in the remains of the main reactor hall, three technicians are looking down into the blazing reactor. A few yards away, Sasha Yuvchenko is straining to hold the steel and concrete reactor hall door open. It has come off its hinges. If it closes, his three colleagues will be trapped inside.
Yuvchenko doesn’t realise that radiation from the door is already attacking his skin. Although the three men on the ledge are only there for a minute, the radiation will kill them in less than two weeks. Sasha Yuvchenko will die of leukaemia in 2008.
The fire crews from Paramilitary Fire Station Number Two arrive at the power station. They are stunned to see that the roof of Reactor No 4 is missing.
Lieutenant Pravik says to his colleague Leonid Shavrey: ‘We’ll really have our work cut out here.’ Shavrey knows they are heading into danger. ‘My hair stood on end,’ he later said.
There is a strange vapour in the air.
Viktor Bryukhanov, the director of the plant, drives through the gates and sees the devastation for the first time. He knows his career is over.
‘I’m going to prison,’ he thinks.
He had overseen the building of the power station and, like many Soviet officials, had cut corners, signed off tests that were never conducted and hit targets by reducing the time spent in making urgent repairs.
Bryukhanov orders that the power station’s underground bunker — built as a command post in case of nuclear war — be opened, then tells his managers to assess the situation in their departments and report back to him. Soon the bunker is filled with 40 men, all frantically making telephone calls.
In the rubble of the kilometre-long turbine hall that links all four reactors, a team of engineers armed with a single torch are searching desperately for their colleague Vladimir Shashenok. They find him barely alive, badly burned and with bloody foam coming out of his mouth. They pick him up and carry him to safety.
Above them on the burning turbine hall roof, firemen Leonid Shavrey and Vladimir Pryshchepa are trying to extinguish the flames. Reluctant to use water because of the danger from exposed electricity cables, they are throwing sand on the fires and beating them out with their canvas hoses.
Contrary to fire regulations, the roof is covered with highly flammable bitumen. Shavrey later recalled: ‘With the slightest increase in temperature, the bitumen immediately caught fire. If you stepped on it, you couldn’t put one foot in front of the other — it tore off your boots.’
The men have no training in putting out fires such as this, and are kicking away burning debris with their boots, not realising that it is radioactive.
Dr Valentyn Belokon, 28, arrives from Pripyat Hospital armed only with painkillers to treat burns. But there are no burns victims yet. A young worker from Reactor No 3 is brought to him suffering from nausea and a violent headache. Belokon assumes the man was drinking the night before.
The young fire chief, Lieutenant Pravik, is concerned that the roof of Reactor No 3 (built close to Reactor No 4 to save money) is now on fire. A westerly wind could spread the flames farther, to Reactors 1 and 2, which are both still operating.
Even though Pravik’s walkie-talkie isn’t working and they have no anti-radiation equipment, he bravely leads his men up a fire ladder to the roof of Reactor No 3.
On the roof of the turbine hall, fireman Leonid Shavrey is getting so hot he removes his helmet. The fishermen, still by the cooling pond, see this and cheer what they think is bravado. ‘He’s taken his helmet off!’ says one. ‘He’s a real hero!’
In Reactor No 4’s control room, Anatoly Dyatlov, the dogmatic deputy chief engineer, is told by a technician that the reactor has blown up. Dyatlov refuses to believe it and heads outside to see for himself. He is stunned by the apocalyptic scene before him.
The local fire brigade chief, Lieutenant-colonel Leonid Teliatnikov, has assembled a team of 28 men to put out the reactor fires. Thoughts of his family flash through his mind, but his main worry is that his men won’t have the strength to keep going until reinforcements arrive.
The condition of the young man Dr Belokon thinks is hung over worsens. He is very pale and continually muttering ‘The horror of it! The horror of it!’ Belokon gives him a sedative. More men appear with similar symptoms.
Leonid Shavrey’s younger brother Petr, who is also a fireman, arrives at the power station not wearing any protective gear, as he was off duty when the emergency call came. He hears Leonid shout from the turbine hall roof that he has no working hoses, so Petr puts two under his arms and clambers up the fire ladder. ‘Protection didn’t matter but time was of the essence to stop the flames spreading,’ he later said.
Lieutenant Pravik and his men come down from the roof of Reactor No 3, as they are all starting to feel sick. Someone calls an ambulance. As Pravik is helped inside, he asks a colleague to phone his wife and tell her to close their apartment’s windows. Pravik’s eyes have turned from brown to blue. He has only days to live.
Fireman Alexander Petrovsky, 24, has taken Pravik’s place and is making his way to the top of Reactor No 3. He is shocked to find only one hose is working.
The power station’s civil defence chief, Serafim Vorobyev, is using a military radiometer designed for use in a nuclear attack to measure radiation. It shows levels are 100 times higher than normal. He runs to Viktor Bryukhanov, the director of the plant, and tells him they need to warn the citizens of Pripyat to stay indoors.
Bryukhanov tells him to go away — he needs time to think.
The firefighters on the roof of the turbine hall have run out of water because the electric pumps have failed. Petr Shavrey, still with no protective gear, has decided the only option is to use water from the cooling ponds. But first he has to guide large fire trucks around the huge amount of debris from the explosion that is surrounding the power station.
As Petr runs in front of the first truck, moving obstacles out of the way, its tyres are punctured by metal spikes. He grabs one with both hands and the skin on his palms peels away.
On top of Reactor No 3, firefighter Alexander Petrovsky goes blind for 30 seconds. When his sight returns, he says to his colleague: ‘Let’s get the f*** out of here!’
All the operators who were missing after the explosions have been accounted for except Valery Khodemchuk, who, unbeknown to his colleagues, was vaporised.
Anatoly Dyatlov from the control room joins the search, with turbine engineer Valeriy Perevozchenko. Their progress through the engine room is hampered by concrete rubble and a fallen crane.
Perevozchenko manages to partially open an office door — and as he shouts Khodemchuk’s name, he is showered by radioactive water cascading from broken pipes overhead. His search for Khodemchuk will ultimately kill him.
Viktor Bryukhanov, the power station’s director, is calling his bosses in Moscow to give them an update.
He downplays the situation, saying that although there has been an explosion, only part of the turbine hall roof has collapsed and the reactor is still intact and being cooled down by his engineers.
Finally realising the firemen and nuclear workers he is seeing are suffering from the effects of radiation, Dr Belokon calls the hospital in Pripyat to ask for potassium iodide — a drug that offers some protection from radiation — to be brought to Chernobyl.
The power station’s civil defence chief, Serafim Vorobyev, is continuing to measure radiation levels, but his clothes and body are so contaminated he can no longer get an accurate reading. Vorobyev angrily confronts his boss, Viktor Bryukhanov, again.
‘There’s no mistake! We have to take action!’
Bryukhanov shoves him away. ‘Get out! Your instrument must be broken!’
Fire chief Leonid Telyatnikov starts vomiting. ‘I thought I was just tired from rushing around so much,’ he said. ‘I was somehow sure I couldn’t get ill because I still had so many things to do.’
After watching the efforts of the firefighters for almost three hours, the fishermen by the cooling ponds are starting to feel ill. Two of those fishing closest to the plant will die.
The newly installed General Secretary of the Communist Party of the Soviet Union, Mikhail Gorbachev, is woken by a phone call telling him there has been a fire at the Chernobyl nuclear power plant. Even he is not told the whole story.
‘In the first hours and even the first day after the accident there was no understanding that the reactor had exploded and there had been a huge nuclear emission into the atmosphere,’ Gorbachev later recalled.
Fire chief Leonid Telyatnikov and his men have arrived at Pripyat hospital. They are chatting and smoking.
They think they are there for a routine post-fire check, but within a few days they will develop radiation burns on their faces, hands and feet.
Six of the men will die. The survivors, including Telyatnikov himself, are later taken to a sterile unit in the specialist radiological wards of Moscow’s Hospital No 6. He won’t be well enough to leave hospital for eight months.
‘Chernobyl showed us that some people are not as conscientious and upright as they should be. We did what we had to do and that’s all,’ he said afterwards.
Anatoly Dyatlov, weakened by sickness and with his shoes soaked by radioactive water, reports to the plant’s director, Viktor Bryukhanov, who asks him how the disaster happened.
‘I don’t know. I don’t understand any of it,’ Dyatlov replies. Both Dyatlov and Bryukhanov will be sentenced to ten years in prison for their role in the disaster.
The sun has now risen, revealing the full horror of the wrecked V.I. Lenin nuclear power station.
The fires are under control, thanks in part to water from the cooling pond. Firefighter brothers Leonid and Petr Shavrey are exhausted. Petr is desperate for a drink and grabs a water hose. ‘What are you doing? It’s filthy!’ a colleague yells at him.
Petr knows by now that the water is probably radioactive but he doesn’t care: ‘It seemed to me that if I didn’t get a couple of gulps, I would collapse and wouldn’t be able to get up again.’
That brief drink will cause lasting damage to Petr’s digestive system.
The deputy fire chief for the region declares optimistically that the emergency is over.
Alexander Akimov and Leonid Toptunov, the two control-room technicians who had argued with Anatoly Dyatlov before the test began, are in the bowels of Reactor No 4 on a futile mission, trying to get water to the wrecked reactor.
Radioactive water is showering down on them as they struggle to turn a large valve. They are becoming increasingly weak and Toptunov frequently has to stop in order to vomit. Akimov’s skin will turn black and he will die in hospital on May 11. He told a colleague his conscience hurt him more than the pain. Toptunov will die three days later. The bravest people at Chernobyl were those most likely to die.
On Sunday, April 27, the city of Pripyat was finally evacuated. The population were told that ‘an unsatisfactory radioactive situation has occurred’ and to leave their pets and take enough food and clothing for three days. They never returned.
In total, almost 350,000 people were moved out of the Chernobyl area.
The outside world knew nothing about the disaster until Monday, April 28, when Cliff Robinson, a Swedish chemist at a nuclear power plant near Stockholm, passed through a radiation detector on his way to clean his teeth at the end of a shift. To his surprise, an alarm went off. Radiation was found on his and other workers’ shoes.
When it was discovered that a cloud of radioactive gas was drifting west across Scandinavia, suspicion immediately fell on the Soviet Union as the source of the contamination.
Later that day, the accident at Chernobyl was the seventh story on the Soviet state television news.
Eventually, the radioactive cloud spread north over the whole of Scandinavia and into Germany and Czechoslovakia, causing toxic rain to fall. Pharmacies in Demark sold out of potassium iodide tablets.
A week after the disaster, radioactive particles in rain fell on North Wales. For more than a quarter of a century, all Welsh lamb produced for human consumption was monitored for radioactivity.
Today, 33 years on, there is still a 30km exclusion zone around the Chernobyl site because radiation levels in the soil remain high. But this so-called ‘dead zone’ is now open to tourists, who visit on day passes.
Nature has flourished and there is an abundance of wildlife. It is illegal to live in the zone but up to 150 people, mainly elderly subsistence farmers, still do. In recent years, a few Ukrainian families — some of them fleeing the Crimean conflict — have moved to live in homes abandoned just outside the exclusion zone.
Buildings in the abandoned city of Pripyat have been stripped of valuable metal by looters. Among the crumbling homes, schools, shops and offices lie toys, shoes and gas masks on the ground.
A total of 31 firemen and workers died at Chernobyl. So radioactive were some of their bodies, they were buried in lead coffins with the lids welded shut.
A World Health Organisation report estimated that, of the 600,000 people across the Soviet Union exposed to the highest levels of radiation, 4,000 would eventually die.
It has been claimed that if all four nuclear reactors at Chernobyl had been damaged by the explosion, most of life on Earth would have been wiped out.
Jonathan Mayo is the author of Hitler’s Last Day: Minute by Minute (Short Books, £8.99).