When the Chernobyl Atomic Energy Station exploded in the early hours of April 26, 1986—precipitating the worst nuclear disaster in history—it resulted almost entirely from human factors.

As the real history of that fateful event continues to be revealed, those factors loom large. Would the Chernobyl explosion, which occurred close to the border between then-Soviet republics of Ukraine and Belarus, have happened if the deputy chief engineer on duty that night wasn’t sleep-deprived? Or if the plant’s administrative head hadn’t succumbed to pressure to cut corners or cover up an earlier accident? How many fewer people would have fallen ill if government officials hadn’t dithered over the question of evacuation? And how much of the broader region might have avoided radioactive fallout if Soviet decision-makers weren’t so steeped in a culture of secrecy and fear?

In his new book Midnight In Chernobyl, author Adam Higginbotham reconstructs the catastrophic events through the experiences of the people who lived through it. Here are seven key protagonists at the heart of the tragedy:

Viktor Brukhanov

Director of the Chernobyl Atomic Energy Station

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Viktor Brukhanov at a sitting of the USSR Supreme Court, 1987.

Viktor Brukhanov had devoted most of his adult life to the communist dream of bringing electricity to the USSR. Appointed to head the Chernobyl nuclear project when he was just 34 years old—and the site of the future plant was nothing more than a deserted field knee-deep in snow—Brukhanov was soft-spoken and well-liked by his staff, but overworked and brow-beaten by his Communist Party bosses. By the spring of 1986, he was nonetheless on the brink of personal triumph: The Chernobyl plant was among the best-performing nuclear stations in the Soviet Union; and Pripyat, the city he had had built to house the plant workers and their families, stood as a beacon of progress—a magnet for specialists from all over the USSR.

With the approach of the May Day holiday, Brukhanov, now 50, was expecting news of a promotion to Moscow, along with state awards for the plant—despite being forced to cut corners and cook the books to meet quotas, and having helped cover up a serious plant accident in 1982. A year later, Brukhanov had also signed off on the launch of the station’s newest and most advanced reactor, Reactor Unit No. 4, even though a key required safety test hadn’t been carried out. When the test was rescheduled to take place during a regular maintenance shutdown of the reactor on April 25, 1986, Brukhanov’s deputy—a Party loyalist who had learned what little he knew of nuclear physics from a correspondence course—didn’t even bother to tell his boss it was happening.

As the administrative head of the entire Chernobyl enterprise, Brukhanov would be held personally responsible for anything that went wrong at the plant. When he first glimpsed the scale of the destruction of Unit Four, his first thought was: “I’m going to prison.”

Anatoly Dyatlov

Deputy chief engineer for operations at the Chernobyl Atomic Energy Station

Igor Kostin/Sygma/Getty Images
Anatoly Dyatlov (seated, leaning forward) is among six defendants attending trial for their role in the Chernobyl disaster.

One of the most experienced nuclear engineers at the Chernobyl station, Anatoly Dyatlov had arrived in Ukraine from the top-secret Laboratory 23 in the Soviet Far East, where he had overseen a team installing reactors in the USSR’s growing fleet of nuclear-powered submarines. But the manner Dyatlov had developed while working at the military laboratory didn’t endear him to the young civilian staff of the nuclear power plant. They found the gray-haired Siberian harsh and dictatorial. And although Chernobyl workers respected him for the depth of his knowledge, many feared or even detested him, his insistence that they unquestioningly follow his orders to the letter and the power he wielded to punish those who disobeyed him.

On the night of the accident, Dyatlov was responsible for overseeing the long-overdue safety test on Reactor No. 4. By the time it finally began, in the small hours of April 26, he was sleep-deprived and as ill-tempered as ever. When the young reactor engineer, Leonid Toptunov, made a mistake soon after taking over at the controls on the midnight shift, Dyatlov insisted on continuing with the test—even though Toptunov, and safety protocols, suggested otherwise.

Leonid Toptunov

Senior Reactor Control Engineer, Fifth Shift, Reactor No. 4

Alexander Zemlianichenko/AP Photo
Vera Toptunova, the mother of Leonid Toptunov, who was a senior reactor control engineer at the Reactor No. 4 of the Chernobyl nuclear plant when it exploded on April 26, 1986, mourns over his grave at Mitino cemetery in Moscow.

A graduate of the Moscow Engineering and Physics Institute—the esteemed Soviet counterpart to the Massachusetts Institute of Technology—Toptunov was just 25 years old when he took the controls of Reactor No. 4 on the night of the accident. Well-trained, independent-minded and something of a ladies’ man, the mustachioed Toptunov—Lenya to his friends—had written his graduate thesis on fine points of reactor physics and knew that under certain circumstances the equipment under his control could be capricious and difficult to master. But he had also been a senior reactor operator for just two months and had never before piloted the reactor through the difficult shutdown process before. He was unaware of the numerous design faults that made accidents not merely possible, but likely, during the normal course of operation.

A series of crucial missteps ensued, any one of which would not in themselves have caused a disaster. But in this case, they fell together in a deadly confluence.

Before the ill-fated test began, Toptunov somehow skipped a step in the process of assuming control of the reactor, accidentally allowing its power output to fall almost to nothing. His training suggested he shut the reactor down, ending the important test before it had even begun. But Anatoly Dyatlov, the senior manager in the room, threatened Toptunov, forcing him to increase the reactor’s power toward the level required for the test. That decision made it susceptible to “reactor runaway,” a terrifying process that, in a split second, could lead to a core meltdown or explosion. At the end of the test, which lasted just 36 seconds, Toptunov pressed the shut-down button of the emergency safety system—the system vulnerable to the most serious of the reactor’s design faults—inadvertently precipitating its destruction. The resulting power surge inside the core led to a pair of explosions that blew the massive concrete lid off the reactor and destroyed the roof and upper reaches of the building around it.

Valery Legasov

First deputy director of the Kurchatov Institute of Atomic Energy, Moscow

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Valery Legasov, Nuclear Energy Institute First Deputy Director (right), was active investigation expert of the Chernobyl nuclear plant disaster.

A happily married father of two grown children, Valery Legasov was 49 years old at the time of the accident and approaching the pinnacle of his career at the top of the Soviet scientific establishment. He had won all but one of the state’s most prestigious prizes for his work and expected to be appointed head of the Institute of Atomic Energy as soon as his boss and mentor, the octogenarian nuclear chief Anatoly Aleksandrov, retired.

The son of a leading Party ideologue, Legasov was a true believer in communism and politically beyond reproach. Living in a grand villa a short walk from his office at the Institute, he was also a keen athlete who skied, played tennis and wrote poetry in his spare time.

He learned that an accident had occurred at the Chernobyl plant in Ukraine during a regular Party meeting on the morning of Saturday April 26. A radiochemistry specialist, he knew little about nuclear reactors, but was ordered to join a government commission, flown to the scene to take control of the emergency and immediately put in charge of containing the consequences of the explosion.

What Legasov witnessed in Chernobyl would change the course of his life: The chaos and incompetence he saw shook his confidence in socialism. The radiation dose he received shattered his health. And his subsequent attempts to reform the Soviet scientific system destroyed his career.

Boris Scherbina

Deputy chairman of the Soviet Council of Ministers; chairman of the government commission in Chernobyl

A memorial plaque for Boris Scherbina on a house in Tyumen where he lived.

A grizzled apparatchik at the head of the USSR’s fuel and energy industries, Scherbina was preparing to give a speech to workers in an oil field near the border with Kazakhstan when he received an urgent summons from Moscow: to fly to Ukraine to take charge of managing the developing disaster in Chernobyl. At 66—balding, bulldog-faced and sure of himself—the minister was an old hand in the ways of the system, its patterns of absurd quotas and preposterous deadlines. As chairman of the government’s Chernobyl commission, Scherbina was responsible not only for bringing the catastrophe under control but investigating its consequences. Without his approval, nothing could happen inside the Exclusion Zone that soon surrounded the remains of Reactor Number Four.

Arriving on the scene on the evening following the explosion, he projected the brash confidence expected of senior Soviet managers. Not only did he disregard the need for personal radiation protection, but he dismissed calls for immediate evacuation of the city of Pripyat as the wayward opinions of panic-mongering weaklings. It was not until almost 36 hours after a pillar of toxic radionuclides began pouring from the wreckage of the reactor that the city’s residents were finally allowed to leave.

Ludmilla Ignatenko

Wife of Sergeant Vasily Ignatenko, member of the third watch, Pripyat city fire station

Igor Kostin/Sygma/Getty Images
<em>Ludmila Ignatenko mourns the death of her husband as she attends t</em>he first commemorative ceremony in homage to liquidators who died from exposure to radiation in the first few weeks after the catastrophe.

Arriving in Pripyat in 1979, fresh from school at the age of 16, Ludmilla took a bed in a student dormitory and a job as a pastry chef in the canteen of the Chernobyl nuclear plant. Soon after, she met Vasily Ignatenko, a young fireman at the city’s Paramilitary Fire Station No. 6. Stocky and thick-set, Ignatenko was charming and talkative—and the champion athlete of the brigade, a regular in the competitive firefighting championships held throughout the USSR. The couple married in 1983 and moved into a small one-bedroom flat in the annex above the fire station reserved for members of the brigade and their families. They gathered blueberries and wild mushrooms in the countryside around the city and barbecued in the garden with their friends from the station. Ludmilla became pregnant with twins, but miscarried; by the spring of 1986, she was expecting once again.

On the night of April 25, the couple was planning a visit to Vasily’s parents, who lived in a village across the border in Belarus, to help them plant a crop of potatoes. He had already received a signed permission slip granting him leave beginning at four in the morning of the 26—in time for the first train out of town. But at around 1:30 a.m., Ludmilla heard three trucks preparing to leave from the station, so she called down to her husband from their balcony to ask where they were going. “The nuclear power plant is on fire,” he said. “Go to sleep. I’ll wake you when I get home.” He never returned.

Maria Protsenko

Chief architect of the city of Pripyat

Courtesy of Maria Protsenko
Maria Protsenko, circa 1986.

Born to Sino-Russian parents in China, raised in the Soviet Union, but excluded from the Communist Party by her foreign birth, Protsenko brought an outsider’s zeal to her work in Pripyat before the accident. Working with scant supplies of precious materials, she imparted beauty and individuality to the standardized buildings of the city. Short but formidable, she patrolled the streets with a ruler, berating construction teams for shoddy workmanship and lashing them with invective as she oversaw plans to expand Pripyat from a town of 50,000 to one of 200,000.

As radiation from the explosion of Reactor No. 4 began to engulf the town, Protsenko was responsible for organizing the evacuation. She planned the escape of every family from each apartment block in Pripyat; and, as more than a thousand buses arrived to take them to safety, she stood at the entrance to the city with a map and gave the drivers instructions on where to go. As the last one departed, Protsenko remained behind, convinced by Party assurances that the citizens would soon return to the homes she had helped build.

Months later, she would still be at her desk in the heart of the newly-created 30-kilometer Exclusion Zone when a KGB officer arrived. His request? To help map a fence intended to permanently seal off the city she helped create from the outside world. 

Adam Higginbotham writes for The New Yorker, The New York Times Magazine, Wired, GQ and Smithsonian. He is the author of the book Midnight in Chernobyl: The Untold Story of the World's Greatest Nuclear Disaster.

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