Chapter 1

A BRIEF HISTORY OF NUCLEAR POWER

Radiation is perhaps the most misunderstood phenomenon known to humanity. Even today, now that its effects are well known, the word ‘radiation’ still elicits a fearful overreaction in most people. During the euphoric decades of study following its discovery at the turn of the century, people held a more carefree attitude in their ignorance. Radiation’s most well-known pioneering researcher, Marie Curie, died in 1934 from aplastic anaemia brought on by her decades of unprotected exposure to the faint, glowing substances in her pockets and desk drawers. Together with her husband Pierre, she built upon German physicist Wilhelm Röntgen’s momentous 1895 discovery of X-rays, by working tirelessly out of, “an abandoned shed which had been in service as a dissecting room of the School of Medicine,1” on the University of Paris’ grounds. Curie herself noted that, “one of our joys was to go into our workroom at night... the glowing tubes looked like faint fairy lights.2” While researching the chemical element Uranium, the pair discovered and named new elements Thorium, Polonium and Radium, and spent significant time studying the effects of unusual waves radiating from all four. Marie dubbed these waves ‘radiation’ and received the Nobel Prize for her work. Until this point in time, the atom was believed to be the absolute smallest thing in existence. It was accepted that atoms were whole, unbreakable, and by themselves formed the building blocks of the universe. Curie’s revelation that radiation is created when atoms split apart was groundbreaking.

Her discovery that the fluorescent Radium destroyed diseased human cells faster than it destroyed healthy cells spawned a whole new industry in the early 20th century, peddling the (mostly imagined) properties of this magical new element to an unsuspecting and misguided public. This craze was encouraged by authority figures, including a Dr. C. Davis, who wrote in the American Journal of Clinical Medicine that, “Radioactivity prevents insanity, rouses noble emotions, retards old age, and creates a splendid, youthful, joyous life.3” Watch and clock faces, fingernails, military instrument panels, gun sights and even children’s toys glowed with radium, hand-painted in factories by young women working for the United States Radium Corporation. The unsuspecting artisans would lick their brushes - ingesting radium particles each time - to keep the tips pointed during the precision work, but years later their teeth and skulls began to disintegrate. Radithor, a ‘modern weapon of curative science’ and one of several medicinal radium products of the time, boasted that it could cure people of rheumatism, arthritis and neuritis.4 Radium cosmetics and toothpastes promising to rejuvenate the skin and teeth were popular for a few years, as were various other proud-to-be-radioactive products, such as radium condoms; chocolate; cigarettes; bread; suppositories; wool; soap; eye drops; The Scrotal Radiendocrinator (from the same genius who brought us Radithor) to enhance a man’s virility; and even radium sand for children’s sandpits, advertised by its creator as, “most hygienic and... more beneficial than the mud of world-renowned curative baths.5” The true hazardous properties of radium, which is around 2.7 million times more radioactive than uranium, were not realised or acknowledged by the public until the 1930s and 40s.6

Fevered7 work to uncover the atom’s secrets continued throughout the early years of the 20th century, as scientists across Europe made many important breakthroughs. By 1932, American physicist James Chadwick made his Nobel winning discovery of the neutron - the final missing piece of the puzzle. With Chadwick’s discovery, the atom’s structure had been unlocked: an atom consists of a nucleus - a central region of protons and neutrons - circled by electrons. The atomic age had truly begun.

Several years later in 1939, physicists Lise Meitner, Otto Frisch and Niels Bohr determined that when an atom nucleus splits and creates new nuclei (a process called nuclear fission), it releases vast amounts of energy, and that a fission chain reaction was possible. The news brought with it the theory that such a chain reaction could potentially be harnessed to create a limitless supply of clean energy for ships, planes, factories and homes, or unleashed from a weapon of unfathomable destructive force. Just two days before World War II began, Bohr and John Wheeler published a paper proposing that fission would work better in an environment where a ‘moderator’ was introduced to slow the speed of neutrons moving within an atom, thus giving them a greater chance to collide and split away from one another.8

As the dangers of radioactive products became more well-known and their civilian popularity collapsed, the desperation and urgency of World War II brought about other remarkable advances in the field. Britain was initially the country most devoted to unlocking the secrets of a fission weapon. Germany had a nuclear program, but it focused on power reactor development. After the Japanese attack on Pearl Harbor on December 7th, 1941, America - which had previously concentrated on nuclear naval propulsion - began its own serious fission research, applying vast resources to the development of an atomic bomb. Within a year, the world’s first nuclear reactor, Chicago Pile-1, was built at the University of Chicago as part of America’s Manhattan Project, supervised by Nobel Laureate for Physics Enrico Fermi. The reactor, famously described by Fermi as, “a crude pile of black bricks and wooden timbers,9” first went critical (achieved a self-sustaining chain reaction) on December 2nd, 1942. Using graphite as its moderator, the reactor had neither a radiation shield nor a cooling system of any kind.10 It was a massive and reckless risk by Fermi, who had to convince his colleagues that his calculations were accurate enough to rule out an explosion.

Joseph Stalin learned that the United States, Britain and Germany were all pursuing fission after a physicist named Georgi Flerov, returning from the front lines, noticed all research on nuclear physics had disappeared from the newly published international science journals. The young man (who now has an artificial chemical element named after him: Flerovium) realised the articles had become classified and wrote a letter to Stalin, in which he stressed the significance of their absence; “build the uranium bomb without delay.11” The dictator took notice and devoted more resources towards the potential of fission energy. He instructed prominent Russian scientist Igor Kurchatov to focus on coordinating espionage information on the Manhattan Project, and to begin surreptitious research into what would be necessary for the Soviets to build a bomb. To do this in absolute secrecy, Kurchatov established a new laboratory, hidden away in Moscow’s wooded outskirts.

The Allied forces declared victory over Germany on May 8th, 1945, and America turned its attention to Japan. Meanwhile, Kurchatov had made rapid progress but was still behind the Americans, who, under Robert Oppenheimer, successfully tested the first atomic device at 05:29:21 on July 16th, 1945, near Alamogordo, New Mexico.12 As this was the first time a weapon of such devastating potential had been tested and the consequences were unproven, Fermi offered to take wagers from the physicists and military personnel present as to whether the bomb would ignite the atmosphere, and, if it did, would it only destroy the state or the entire planet.13 Codenamed ‘Trinity’, the blast dug a crater 1,200 feet in diameter, and produced temperatures of ‘tens of millions of degrees Fahrenheit’. Frightened by what he had witnessed, physicist George Kistiakowsky said, “I am sure that at the end of the world, in the last millisecond of the Earth’s existence, the last man will see what we have just seen.14” A mere three weeks later, on August 6th, a modified Boeing B-29 Superfortress dropped the first atomic bomb on the city of Hiroshima, Japan, and its population of 350,000 people. It converted 0.6 grams of uranium into a force of energy equivalent to 16,000 tons of TNT. A second bomb followed three days later at Nagasaki. Over 100,000 people - most of them civilians - died instantly. Japan surrendered within days; World War II was over.

Despite the horrific display, fear in some parts of the world gradually gave way to wonder and optimism at how such a small device could produce so much energy. Even so, weapons development continued. Russia’s first plutonium-producing reactor (plutonium does not occur in nature) came online at Mayak in 1948, followed by their first atomic bomb test in the deserts of Kazakhstan during August of 1949.15 Outside16 the Soviet Union, attention in the West turned towards applying fission’s unprecedented energy potential to civilian purposes. Five days before Christmas of 1951, America’s small ‘Experimental Breeder Reactor 1’ became the world’s first electricity-producing reactor when it generated sufficient electricity to light four 200-watt light bulbs.17 Two years later, America’s President Eisenhower announced the ‘Atoms For Peace’ program during a speech in which he pledged the United States’, “determination to help solve the fearful atomic dilemma - to devote its entire heart and mind to find the way by which the miraculous inventiveness of man shall not be dedicated to his death, but consecrated to his life.18” Part genuine attempt to push for civilian nuclear infrastructure and further research, part propaganda program to silence global critics of nuclear energy and provide a cover for a nuclear arms build-up, Atoms For Peace ultimately lead to the creation of America’s nuclear power stations.19

One of Russia’s existing military plutonium production reactors was modified for electricity generation, and in June 1952, AM-1 - short for ‘Peaceful Atom 1’ in Russian - became the world’s first civilian nuclear power station, generating 6-Megawatts electric (MWe).20 It was a graphite-moderated, water-cooled configuration, which served as a prototype for Chernobyl’s RBMK reactors. Two years later, Queen Elizabeth II opened Britain’s first commercial 50 MWe nuclear reactor at Windscale, as the government announced that Britain had become, “the first station anywhere in the world to produce electricity from atomic energy on a full industrial scale.21”

Both dominant superpowers recognised the obvious potential naval benefits of a power source that only needs to be refuelled every few years, and worked hard to reduce the scale of their reactor designs. By 1954, miniaturisation had progressed far enough for the United States to launch the world’s first nuclear submarine, the USS Nautilus, and both America and Russia had nuclear-powered surface ships within a further five years.

In 1973, the first high power RBMK-1000 reactor - the same type used at Chernobyl, which was under construction at the time - started up in Leningrad. America and most Western countries had now settled on a Pressurised Water Reactor design - water moderated and cooled - as the safest option. From the late 1970s until early 2000s, construction of new reactors stalled: a consequence both of the world’s reaction to the Chernobyl and Three Mile Island incidents, and of improvements to the power capacity and efficiency of existing reactors. Nuclear power reached its peak in terms of number of reactors operating in 2002, with 444 in use, but it wasn’t until 2006 that the highest level of nuclear-generated electricity record was set: 2,660 Terawatt-hours for the calendar year.22

As of 2011, nuclear power provided 11.7% of the world’s electricity, with over 430 commercial nuclear reactors operating in 31 countries.23 Combined, they generate 372,000 Megawatts of electricity. The current largest nuclear plant is Japan’s Kashiwazaki-Kariwa Nuclear Power Plant, which generates 8000MW from 7 reactors, though it is not currently in use. France is the country most dependent on nuclear power, providing roughly 75% of its electricity through nuclear power plants, while America and Russia both hover around the 20% mark. Slovakia and Hungary were the only other countries to produce more than 50% of their electricity from nuclear power as of the end of 2014, though Ukraine, where Chernobyl is situated, still relies on nuclear for 49% of its energy.24

Nuclear electricity has become the power source of choice for many large naval vessels. This peaked in the early 1990s, when there were more nuclear reactors in ships (mostly military - over 400 in submarines)25 than there were generating electric power in commercial power plants worldwide.26 This number has since dwindled, but there are still some 150 ships and submarines containing nuclear reactors. Russia is constructing the world’s first floating nuclear power station barge for use in the Arctic, which could be towed to wherever power is needed. Containing two modified naval reactors from ice-breakers and operating at a capacity of 70MW, the Akademik Lomonosov is expected to be delivered in September 2016.27 While the Russians will claim the title of first barge to produce nuclear power, floating power stations are not a new idea. The United States built the first floating nuclear power station inside a converted ex-WWII Liberty Ship in the late ‘60s, though none operate today. China is also entering the market, and expects its first floating nuclear power station to begin generating electricity some time in 2020.28

 

Previous Accidents

 

It is impossible to say for certain how many people have died as a result of nuclear accidents, because cancers and other medical disorders caused by exposure to radiation are often indistinguishable from any other cause. Only estimates can be made. As with Marie Curie, it is likely that many of the early pioneers of radiation research (and early patients receiving overpowered X-rays)29 were killed later in life - via cancer or radiation-related illnesses - by that which they studied. Even though Curie’s work deteriorated her health - and the health of her colleagues - until her eventual death in 1934, she continued to deny the hazards of radiation. Curie’s two children - who continued her work and won their own Nobel Prize - were also killed by radiation.30 Even deaths resulting from acute radiation syndrome have no reliable statistics, as the Soviet Union covered up all serious accidents until the Chernobyl disaster. It is possible that secretive, nuclear-capable countries notorious for bureaucratic corruption such as Pakistan, Iran and North Korea may continue to do so.

There are around 70 nuclear and radiation accidents involving fatalities on public record, almost all of which resulted in less than 10 deaths,31 although there have without doubt been more which will have been kept hidden. Interestingly, many of these events are attributed to miscalibration or theft of medical radiotherapy equipment.

For instance, more than 240 people were exposed to radiation in Goiânia, Brazil in September 1987, after thieves dismantled a steel and lead capsule stolen from a nearby semi-demolished hospital. The capsule, which contained radioactive caesium from a radiotherapy machine, was stored in the back garden of one of the men. There, over the course of several days, during which both thieves became ill, the pair hacked away at the capsule until they pierced its protective steel casing. The men attributed their symptoms to something they had eaten, not suspecting their loot, and subsequently sold the compromised capsule to a scrapyard dealer named Devair Ferreira. That night, Devair noticed the material inside gave off a blue glow and assumed it to be valuable - even supernatural. To protect it, he stored the capsule in the home he shared with his wife Gabriela, and distributed powder and fragments among friends and family. This included Devair’s brother, who gave some of the caesium powder to his six-year-old daughter. Enticed by the magical blue glow, she played with it, spreading it on herself like glitter, and ingested the radioactive particles. Two of Devair’s employees spent several days further dismantling the capsule, to extract the lead it contained.

Gabriela was the first to notice that she and everyone around her was becoming seriously ill. Despite being told by a doctor that she, too, was having an allergic reaction to something she ate, she was convinced the culprit was the unusual material that had so fascinated her family. Gabriela reclaimed the capsule from a second scrap merchant, to whom it had now been resold, and took it - by bus - to a nearby hospital, where she declared that it was, “killing [her] family”.32 Her foresight prevented the incident from being far more serious.

The caesium then sat unidentified in a courtyard until the next day, when a visiting medical physicist, who had been asked to investigate by a doctor at the hospital, “arrived just in time to dissuade the fire brigade from their initial intention of picking up the source and throwing it into a river”.33 Gabriela perished, along with the little girl and Devair’s two employees. Devair Ferreria himself survived, despite receiving a higher dose than any of the four fatalities. Because the capsule had been opened and transported several times during the two-week incident, several areas of the city were contaminated, necessitating the demolition of multiple buildings.34

The total number of fatalities from accidents relating to civilian nuclear power is relatively low - far lower than deaths related to conventional coal, oil or hydro-power accidents.

To place this in perspective, consider the death tolls of the worst conventional power-related accidents. Coal mining, notorious for being dangerous, contributes a huge number of deaths. A list of just 32 notable coal mining accidents totals almost 10,000 fatalities,35 while all American coal-mining accidents since 1839 account for over 15,000 deaths.36 The worst of these incidents occurred on April 26th 1942, exactly 44 years prior to the Chernobyl disaster, when a gas explosion at China’s Benxihu Colliery lead to the deaths of 1,549 miners.37

The Nigerian National Petroleum Corporation’s Jesse Oil Pipeline exploded in 1998, killing over 700 people - one of dozens of similar incidents in the country. Its exact cause was never determined because everyone in the vicinity was killed, but the explosion was either due to poor maintenance or - just as likely - deliberate sabotage by scavengers seeking to steal oil.38 Another striking oil/gas accident happened near the Russian city of Ufa. When a leak sprang in a large gas pipeline near a remote section of the Trans-Siberian railway, instead of locating and fixing it, workers increased the pipe’s gas pressure to compensate. This gradually filled the valley through which it ran with a flammable mixture of benzine and propane-butane, until people up to 5 miles away reported smelling gas. On June 4th, 1989, two trains carrying a total of around 1,200 family holidaymakers, running in opposite directions, passed each other near the leaking pipeline. Sparks from their wheels ignited the lingering gas, triggering an explosion of, “frightening might” - 10,000 tons of TNT. Both locomotives and their 38 carriages were incinerated and flung from the tracks, according to Mikhail Moiseyev, the Army’s General Chief of the Soviet General Staff. The explosion was so powerful, “that it felled all trees within 4 kilometers,” he said. The accident claimed the lives of 675 people, over 100 of whom were children.39 (Linked Footnote)40

Hydro-41power’s most catastrophic accident occurred during Super-Typhoon Nina in 1975, after a year’s worth of rain fell on China’s Henan Province in 24 hours. The Beijing-based Central Meteorological Observatory had predicted 100mm of rainfall, leaving people unprepared for what followed. At its peak, 190mm fell in a single hour.42 “When the rain continued, the days were like nights as rain fell like arrows,” survivors were quoted as saying by official records. “The mountains were covered all over by dead sparrows after the rain.” Just after 1am on August 8th, the Banqiao Dam failed with what sounded, “like the sky was collapsing and the Earth was cracking.43” An unstoppable deluge of water then prompted a chain reaction that overwhelmed 61 other dams and reservoirs. The resulting 11 kilometer-wide, 50 km/h wave ultimately killed a staggering 171,000 people, destroyed the homes of 11 million more, and wiped out entire communities.44

A number of nuclear accidents are worth highlighting. One early example is that of a 6.2-kilogram piece of plutonium, which went critical on two separate incidents at the Los Alamos nuclear research laboratory in New Mexico, US. It was subsequently given the nickname ‘The Demon Core’. The first occasion occurred on August 21st, 1945, when Harry Daghlian, working alone, dropped a neutron-reflective brick onto the core by mistake, causing an instantaneous and uncontrolled chain reaction.45 He knew what was happening, but had to partially disassemble his experiment to remove the brick, by which time he had already received a fatal dose. He died twenty-five days later. Despite a review of safety protocol following the accident, another event with the same piece of plutonium occurred less than a year later when physicist Louis Slotin allowed two neutron-reflecting half-spheres to envelop the core by accident, thus causing it to go critical. Leaning over the core, he received a fatal dose in less than a second and died after, “a total disintegration of bodily functions,” nine days later.46 Following this second accident, hands-on experiments halted and special remote control machines were used instead. After the war, scientists placed the Demon Core into a nuclear bomb and detonated it underwater at Bikini Atoll as part of America’s Operation Crossroads - a study intended to test the effects of nuclear weapons on Navy ships.

Britain’s worst nuclear accident was a direct consequence of the short-sighted conversion of the two existing plutonium-producing reactors at Windscale (now Sellafield) in Cumbria to instead produce tritium, which is required for a thermonuclear bomb. The graphite-moderated, air-cooled reactors were not well suited to the task, which required a hotter, more intense fission reaction than they were designed for. Engineers made modifications inside the core that enabled the production of tritium at the cost of reduced safety. When initial tests succeeded with no apparent problems, full-scale production of tritium began unabated. Nobody knew that modifying the reactor had dangerously changed the distribution of heat within the core - the reactor was now growing far too hot in areas which had earlier been cool and lacked the proper sensors for measuring temperature. When the Windscale reactors were designed and built, British scientists were inexperienced with how graphite responds to being bombarded with neutrons, and were unaware that it ‘suffers dislocations in its crystalline structure, causing a build-up of potential energy,’ which could then spontaneously escape in a dangerous burst of heat. The problem was not discovered until the reactors became operational, by which time it was too late for a redesign. A solution came in the somewhat unreliable form of a slow annealing process, where the graphite was heated and then allowed to cool, which returned the heated graphite to its initial state with a gradual release of built up energy.

On October 7th, 1957, workers at Windscale performed a routine annealing process by heating up and then shutting down the reactor to wait for it to cool, but soon noticed that the release of energy was not happening as expected. The operators heated the core a second time, but by the morning of the 10th realised something was wrong - the core temperature should have fallen as the graphite energy release slowed, but it had not. Uranium fuel inside the reactor had caught fire. (Note, it was first reported to be a graphite fire, but later analysis showed it was a uranium fire.) Unaware of this critical piece of information, the operators increased the flow of air being blown into the core to help it cool down, but this only fanned the flames. At this point they noticed the radiation monitors mounted on top of the chimney were off the scale. A quick manual inspection of the reactor revealed that it was on fire, and had been for almost 2 full days. After frantic efforts to first use carbon dioxide and then water to extinguish the flames, Windscale’s manager, Tom Tuohy, evacuated all but the vital personnel, shut off the cooling fans and closed the ventilators. He then climbed up the towering chimneystack several times for a direct view down into the rear of the reactor to be sure the fire was out. He later said, “I did stand to one side, sort of hopefully, but if you’re staring straight at the core of a shutdown reactor you’re going to get quite a bit of radiation.47”

This incident - dire as it was - would have been a disaster had it not been for “Cockroft’s Folly”. Sir John Cockroft was the Director of Britain’s Atomic Energy Research Establishment and had won the 1951 Nobel Prize in Physics, along with Ernest Thomas Sinton Walton, “for their pioneer work on the transmutation of atomic nuclei by artificially accelerated atomic particles.48” Mid-way through Windscale’s construction, Cockroft intervened and insisted that expensive radiation filters be retrofitted, overruling all objections. His filters were added, resulting in the iconic chimney bulges which came to be known as ‘Cockroft’s Folly’ - until their existence prevented a catastrophic spread of radioactive particles across the landscape. The full facts of the accident were not made public for nearly 30 years, but a 1983 report by the National Radiological Protection Board estimated that 260 people were likely to have contracted thyroid cancer because of the incident, and over 30 more will have either already died or, “sustained genetic damage that will bring disease or death to their descendents”.49 The Windscale incident was regarded as the worst reactor accident until Three Mile Island, and is a fascinating story in and of itself. I recommend further reading.50 (Linked Footnote)51 (Linked Footnote)52

America’s53 first serious reactor accident, and the only known fatal reactor incident in US history, took place on January 3rd 1961, at the US Army’s experimental SL-1 reactor. Engineers were performing maintenance requiring the large, main control rod to be disconnected from its drive motors. Reconnection necessitated that the operator, Army Specialist John Byrnes, manually lift the rod up by a few centimeters. He withdrew the rod too far, causing the reactor to go critical in an instant. Water inside the core explosively vaporised, causing a pressure wave to hit the lid from inside the reactor and launching the reactor vessel upwards, firing the control rods and shield plugs from their housings. One shield plug penetrated up through Construction Electrician Richard C Legg’s groin and out of his shoulder, impaling and pinning him to the ceiling. He had been standing on top of the reactor. Barnes himself was killed by water and steam, and a nearby trainee died later of his injuries. Some suggest that this may not have been an accident at all, but rather a murder-suicide, as Byrnes suspected his wife was having an affair with another operator on his shift.54

Two submarine reactor accidents stand out. On July 4th 1961, Soviet ballistic missile submarine K-19 developed a serious leak in its reactor coolant system, causing a complete failure of the coolant pumps. Even though the control rods had been inserted into the core to neutralise the reaction, decay heat (the process of decaying radioisotopes creating heat as they lose energy - the same thing is a significant contributor to the heat at the Earth’s core) rose the temperature inside to 800°C. During construction, a welder had allowed a drop of solder to land on a coolant pipe, causing a microscopic crack. During a training exercise, the crack burst open under pressure. Captain Nikolai Zateyev realised he had no choice but to create a makeshift cooling system for the reactor by cutting off an air vent valve and welding a water pipe to it. “It would have been Chernobyl, only 30 years earlier,” said crew member Alexander Fateyev. The emergency solution worked, but the whole crew received large doses of radiation and the six brave men who entered the reactor compartment to work on the pipes died of radiation poisoning within weeks. Sixteen more would follow them. “Right on the spot, their appearances began changing,” recalled Captain Zateyev, after the fall of the Soviet Union. “Skin not protected by clothing began to redden, face and hands began to swell. Dots of blood began to appear on their foreheads, under their hair. Within two hours we couldn't recognize them. People died fully conscious, in terrible pain. They couldn't speak, but they could whisper. They begged us to kill them.” The event was later depicted in the movie ‘K19: The Widowmaker’, starring Harrison Ford.55

Over56 two decades later on August 10th, 1985, the Echo-II class submarine K-431 sat on the choppy waters of the Chazhma Bay naval facility southeast of Vladivostok, at the tri-border junction with Russia, China and North Korea. The 20-year-old sub was on the final stage of a 10-step refuelling process. This required the 12-ton reactor lid to be detached from its control rods, then lifted by a crane arm extended across the water from a nearby refuelling service ship, to allow new fuel assemblies to be placed. The reactor lid had been replaced, the control rods reattached and the cooling system refilled with water, but workers on the submarine discovered that the lid had not formed a perfect seal. Without seeking the proper authorisation, they craned-up the lid by a few centimeters to fix the problem, leaving the rods attached to save time. At this worst possible moment, a Navy torpedo boat sped by, creating a wake violent enough to rock the refuelling ship and its crane arm. The attached lid and control rods lurched away from the core and the reactor instantly went critical, causing a steam explosion that blew the core’s contents out of the compartment and destroyed the submarine’s pressure hull. Eight officers and two workers were killed by the explosion, while an additional 290 workers received significant doses of radiation in the 4-hour battle to bring the resulting fire under control.57 The accident remained secret until a book of declassified documents was published in 1993, following the fall of the Soviet Union.

 

Kyshtym

 

The event that came to be known as the Kyshtym Disaster happened near Russia’s closed city of Chelyabinsk-65, 120 kilometers from the border with Kazakhstan. The existence of closed cities was a well-guarded secret during the Cold War - even among the USSR’s own citizens - because they housed workers of nearby nuclear facilities, weapons factories and other significant industrial sites. They did not appear on any map or road sign, visitors were prohibited without express permission from the Government, and residents who left the city were forbidden from discussing where they lived or worked with outsiders. As a result of this secrecy, the disaster was named after Kyshtym, the nearest known town. Besides being the location of one of Russia's largest tank factories, Chelyabinsk-65 was near to the Mayak nuclear plutonium-producing reactors (for nuclear weapons) and reprocessing plant - one of the country’s biggest nuclear facilities, and the site where their first nuclear weapon was produced. The Soviet Government was not known for its compassion for the safety its people or the environment, and Mayak was no exception, as the site played host to a long list of nuclear accidents and biological atrocities in the decades after its completion in 1948. By the time of the catastrophe which would claim Kyshtym’s name, the Mayak facility had already contaminated the surrounding area with constant dumping of nuclear and chemical waste into the nearby Techa-Iset-Tobol river system and lakes, to such an extent that it would be regarded as the most contaminated place on Earth decades later.

Mayak cooled some of its nuclear waste in buried steel and concrete storage tanks, each containing 300m³ (around 80 tons) of materials. At some time during September 1957, one of the tanks’ cooling systems failed. Nobody noticed as the temperature within began to rise due to decay heat, even as it reached a temperature of approximately 350°C. On the afternoon of September 29th, 1957, built-up pressure caused the tank to explode with the force of 70 - 100 tons of TNT, throwing off the 160-ton concrete lid, damaging the two adjacent tanks and spewing 740,000 terabecquerels of radioactive particles into the air - twice the amount released by Chernobyl.

The prevailing northeasterly wind carried the radioactive plume over an area of up to 20,000 square kilometers (km²), with serious contamination covering around 800km². Reliable statistical health information is impossible to find as officials hid the accident from public view and no registry was created to track the health of those affected. After an initial (unjustifiable) delay of a week, over 10,000 people were evacuated from their homes during the following two years. Doctors diagnosed those who fell ill with ‘the special disease’, because they could not refer to radiation as long as the Mayak facility was a secret. It worked: the accident remained hidden until 1976 when Zhores Medvedev (who went on to write the excellent ‘Legacy of Chernobyl’) exposed the event in an article for New Scientist. The incident was then given a rating of 6 on the International Nuclear Events Scale, making it the third worst nuclear accident in history. Lev Tumerman, a Soviet scientist who had passed through the area in 1960, supported Medvedev’s assertions, stating that, “about 100 kilometres from Sverdlovsk, a highway sign warned drivers not to stop for the next 20 or 30 kilometers and to drive through at maximum speed. On both sides of the road, as far as one could see, the land was ‘dead’: no villages, no towns, only the chimneys of destroyed houses, no cultivated fields or pastures, no herds, no people...nothing.58” It transpired that the CIA had known about the incident for over fifteen years, but had kept silent because they didn’t want to spread fear of the United States’ own nuclear facilities among the population.

Mayak was the location of another serious radiation accident ten years later. Lake Karachay is a small lake on the site which had been used as a dump for radioactive waste for over a decade. Dumping into the lake continued after the explosion and by the mid-1960s it was so contaminated that standing on its shores at the time would give you a lethal dose within an hour. 1965 and ‘66 were particularly dry years, causing the lake to begin to dry out. During a drought in the spring of 1967, low-level areas of the lake evaporated completely, exposing radioactive sediments to the atmosphere. A violent storm swept through the area, blowing the contaminated particles several hundred kilometers from the almost bone-dry lake bed and depositing 185,000 terabecquerels (the same amount released by the Hiroshima bomb) of radioactivity onto half a million people - the same people irradiated by the Mayak explosion ten years earlier. Years later, the lake was filled with thousands of hollow concrete blocks to prevent the same thing from ever happening again.59 (Linked Footnote)60 (Linked Footnote)61 (Linked Footnote)62

Soviet63 accidents were not isolated to military installations. Operators at the Beloyarsk Nuclear Power Plant received serious radiation exposure in 1977 after a partial meltdown, and again a year later during a reactor fire. Despite all these events, Soviet authorities continued to maintain in public that their nuclear program was absolutely safe. Lev Feoktistov, Deputy Director of the I. V. Kurchatov Institute of Atomic Energy - now Russia’s leading nuclear research and development institution, named after its founder - co-authored an article in Soviet Life magazine a year before the Chernobyl accident. In it, he stated that, “in the 30 years since the first Soviet nuclear power plant opened, there was not a single instance when plant personnel or nearby residents have been seriously threatened: not a single disruption in normal operation occurred that would have resulted in the contamination of the air, water or soil. Thorough studies conducted in the Soviet Union have proved completely that nuclear power plants do not affect the health of the population.64”

 

Three Mile Island

 

The most well-known accident at a nuclear plant prior to Chernobyl occurred at the Three Mile Island (TMI) power station in Pennsylvania, United States on March 28th, 1979, when a cooling fault lead to the meltdown of the site’s brand-new second reactor. Although nobody was injured, it is considered to be the worst accident in the history of US nuclear energy. Much like Chernobyl, it combined a complicated series of oversights and mistakes to create a near-disaster.

Eleven hours before the accident began, while attempting to clean a condensate filter, a stubborn blockage compelled workers to blow compressed air into a water pipe, intending to let the water’s force clean the filter. This worked, but it also caused an inadvertent trickle of water to leak into the feedwater pumps’ control system. The resulting fault went undiscovered until the accident concluded.

Eleven hours later, at 4am, a minor malfunction in the secondary, non-nuclear water cooling circuit prevented proper heat dissipation and caused the primary coolant temperature to rise. TMI’s reactor shut itself down, halting the chain reaction, but decay heat continued to raise the core temperature. This alone wasn’t a problem, as nuclear reactors are designed with decay heat in mind and multiple automatic, redundant, independent safety systems are in place to prevent an accident. By an unlucky coincidence, however, the three auxiliary water coolant pumps that also activated could not pump any water because their valves were closed for routine maintenance. Decay heat in the core created a pressure build-up much like it had at Mayak, prompting the pressuriser’s pilot-operated relief valve (PORV) to open, which stabilised the pressure level. Then things started to go wrong. The mechanical fault from 11 hours prior came into play, preventing the valve from closing again. Reactor 2’s operators incorrectly assumed that the valve had closed, because their control panels indicated that a ‘close’ signal had been sent to it - not what the valve’s actual position was. As a result, they failed to notice that coolant was escaping from the system for several hours, leading them to make several wrong-moves.

With coolant rapidly escaping, the control computer injected emergency water from pressurised tanks into the system to compensate. Although a significant volume of this injected water also escaped through the PORV, enough was flushed past the pressuriser’s water sensors to trick the operators into believing that there was actually too much water in the cooling system. They responded by reducing the flow of replacement water, unintentionally starving the reactor of water and allowing dangerous steam to build up within the primary cooling system. When steam bubbles form in fluid and subsequently collapse, they emit high-pressure shock waves that can damage the pipes. This is known as cavitation. TMI’s control room personnel, who were still under the impression there was sufficient water travelling around the cooling system, turned off the pumps to prevent this. Diminishing water levels gradually exposed the top of the fuel elements inside the core, allowing them to reach extreme temperatures and melt, which released radioactive particles into the remaining water. During all of this, the reactor operators struggled to figure out what was wrong.

It was only when the control room shift changed at 6am that fresh eyes noticed the PORV temperature was higher than expected. At 6:22 am operators closed a backup block valve between the relief valve and the pressuriser. The coolant loss halted, but by now superheated steam was preventing the inertia circulation of water, so they slowly increased the pressure by injecting pressurised water into the cooling system. Over 16 hours after the disaster began, the pressure climbed high enough to restart the primary pumps without fear of cavitation. It worked: the reactor temperature fell, but not before about half of the core and 90% of the fuel’s safety cladding had melted. The event was saved from being catastrophically worse by the reactor’s pressure vessel - an enormous metal shield surrounding the core, containing its molten radioactive remains. The same vital containment that Chernobyl’s RBMK reactors lacked.65

As66 at Chernobyl, operator error was shouted loud as the fundamental cause of the accident, but US President Jimmy Carter’s own President’s Commission came to more pragmatic conclusions seven months later. Their report noted many areas where improvements could be made. “While training may have been adequate for the operation of a plant under normal circumstances, insufficient attention was paid to possible serious accidents.” It also acknowledged that some, “operating procedures, which were applicable to this accident, are at least very confusing and could be read in such a way as to lead the operators to take the incorrect actions they did.” Problems with the confusing control interface were addressed too: “The control room, through which the operation of the [reactor] is carried out, is lacking in many ways. The control panel is huge, with hundreds of alarms, and there are some key indicators placed in locations where the operators cannot see them... During the first few minutes of the accident, more than 100 alarms went off, and there was no system for suppressing the unimportant signals so that operators could concentrate on the significant alarms.” Finally, the timeless problem of failure to learn from past mistakes also contributed, as it transpired a similar incident had happened at another U.S. plant over a year earlier, but American reactor operators were not informed.67

While these events are disturbing when taken in isolation, it’s important to remember that nuclear power remains by far the least harmful method of energy production overall. Using historical production data, NASA scientists calculated in 2013 that nuclear power has actually prevented an average of 1.84 million air pollution-related deaths and 64 gigatonnes of CO2-equivalent greenhouse gas emissions that would have resulted from fossil fuel burning between 1971 and 2009.68 That data was based on European and US plants, which tend to be cleaner than elsewhere, meaning those numbers are likely to be far higher in reality. A study by Tsinghua University associate professor Teng Fei estimates that Chinese coal pollution caused a distressing 670,000 deaths in 2012,69 while the global average coal deaths is 170 per Terawatt-hour (TWh) of generated electricity. For comparison, data from 2012 shows that oil-generated electricity causes 36 deaths/TWh; biofuel, 24 deaths/TWh; wind power, 0.15 deaths/TWh; hydro-electricity, if you factor in the Banqiao disaster, causes 1.4 deaths/TWh, and still causes widespread devastation to the surrounding landscape if you don’t. Nuclear power, including Chernobyl and Fukushima, is responsible for 0.09 deaths per Terawatt-hour.70