5 Unknown Nuclear Disasters: Chernobyl Is Far from the Only One
By Marcia Wendorf, Interesting Engineering, 1 August 2019.
By Marcia Wendorf, Interesting Engineering, 1 August 2019.
Chernobyl is not the world's only nuclear disaster, there are plenty of others to keep you up at night.
The recent miniseries "Chernobyl" has scared the daylights out of everyone, but Chernobyl is far from the world's only nuclear disaster. Here are some others that are also worth knowing.
1. The Kyshtym Disaster
In September 1957, Ozyorsk, Russia was a closed city, built around the Mayak plant which produced plutonium for both nuclear weapons and fuel.
After scrambling to build the Mayak plant between 1945 and 1948, all six of its reactors initially dumped high-level radioactive waste directly into Lake Kyzyltash. When it became contaminated, they moved on to dumping into Lake Karachay, which also became contaminated.
In 1953, workers built a storage facility for liquid nuclear waste, but that waste was being heated by residual decay heat from the nuclear reaction. The coolers around one of the tanks failed, and on September 29, 1957, that tank exploded with the force of between 70 to 100 tons of TNT.
While there were no immediate casualties, the explosion released an estimated 20 MCi (800 PBq) of radioactivity into the air. A plume containing 2 MCi (80 PBq) of radionuclides, primarily caesium-137 and strontium-90, moved toward the northeast and contaminated an area of more than 52,000 square kilometers (20,000 sq miles).
At least 270,000 people lived in that area, which is referred to as the East-Ural Radioactive Trace (EURT).
In an attempt to maintain secrecy, no evacuation was ordered, but a week later, on October 6, 1957, 10,000 people were removed from their homes.
Estimates of the death toll caused by the accident go from 200 to more than 8,000, depending on the study. A 2001 work stated that the accident caused 66 diagnosed cases of chronic radiation syndrome.
Amazingly, it wasn't until 18 years later, in 1976, that the full scope of the disaster was disclosed by Zhores Medvedev in the publication the New Scientist.
In 1968, the Soviet government disguised the EURT area by creating East Ural Nature Reserve, with access allowed to only authorized personnel. Documents describing the disaster were only declassified in 1989.
On the International Nuclear Event Scale (INES), Kyshtym is rated a 6, making it the third-most serious nuclear accident behind only the Fukushima Daiichi nuclear disaster and the Chernobyl disaster, which are both Level 7.
2. The Windscale Fire
Less than two weeks after Kyshtym, a fire broke out in Unit 1 of the two reactors at the Windscale facility located in what is now known as Sellafield, Cumbria, UK.
The two reactors were created because of Britain's need for an atomic weapon following World War II. Determining that a uranium enrichment plant would cost ten times as much to produce the same number of atomic bombs as a nuclear reactor, the decision was made to build a nuclear reactor that would produce plutonium.
The cores of the reactors were comprised of a large block of graphite, with horizontal channels drilled through it for the fuel cartridges. Each cartridge consisted of a 12-inch-long (30 centimeters) uranium rod encased in aluminum.
The reactor was cooled by convection through a 400-foot (120 m) tall chimney. When Winston Churchill committed the UK to create a hydrogen bomb, the fuel loads at Windscale were modified to produce tritium, but this also meant that the core became hotter.
On the morning of October 10, 1957, the core began to uncontrollably heat, eventually reaching 400 degrees C. Cooling fans were brought in to increase the airflow, but just worsened the problem. It was then that operators realized that the core was on fire.
Workers tried dousing the core first in carbon dioxide, then in water, but both proved ineffective. What finally worked was cutting off air to the reactor building, which starved the fire.
The fire caused the release of radioactive radionuclides across the UK and Europe, including an estimated 740 terabecquerels (20,000 curies) of iodine-131, 22 TBq (594 curies) of caesium-137 and 12,000 TBq (324,000 curies) of xenon-133.
By comparison, the 1986 Chernobyl explosion released far more, and the Three Mile Island accident in 1979 in the U.S. released 25 times more xenon-135 than Windscale, but less iodine, caesium, and strontium. The atmospheric release of xenon-133 by the Fukushima Daiichi nuclear disaster was similar to that released at Chernobyl, and thus, high above what the Windscale fire released.
There were no evacuations of the surrounding area, but it has been estimated that the incident caused 240 additional cancer cases. For a month after the accident, milk coming from 500 square kilometers (190 sq mi) of the nearby countryside was destroyed.
The reactor tank has remained sealed since the accident and still contains about 15 tons of uranium fuel. The reactor core is still slightly warm due to continuing nuclear reactions. It is not scheduled for final decommissioning until 2037. On the International Nuclear Event Scale, Windscale ranks at level 5.
3. Soviet Submarine K-19
K-19 was one of what the Soviets called their Project 658-class submarines, while NATO called them Hotel-class. They were the first generation of nuclear submarines equipped with nuclear ballistic missiles.
Commissioned on April 30, 1961, K-19 was snake bit from the start. On its initial voyage, on July 4, 1961, it was conducting exercises off the coast of Greenland when suddenly, pressure in the reactor's cooling system dropped to zero due to a leak.
The emergency SCRAM system immediately inserted the control rods, but due to decay heat, the reactor's temperature rose to 800 degrees C (1,470 degrees F). The accident released steam containing fission products throughout the ship through the ventilation system.
The captain ordered the ship's engineering crew to fabricate a new cooling system, but this required them to work within the radioactive area. The jury-rigged cooling water system prevented a complete meltdown of the reactor core.
American warships nearby had picked up K-19's distress call and offered to help, but K-19's captain, fearful of giving away Soviet military secrets, refused. Instead, K-19 sailed to meet up with a diesel-powered Soviet submarine. The accident had irradiated K-19's entire crew, as well as the ship and some of her ballistic missiles.
Within a month, all eight members of the ship's engineering crew died of radiation exposure. They are Boris Korchilov, Boris Ryzhikov, Yuriy Ordochkin, Evgeny Kashenkov, Semyon Penkov, Nicolai Savkin, Valery Charitonov, and Yuriy Povstyev.
Within the next two years, 15 other sailors died of radiation-related illnesses.
Towed into port, K-19 contaminated a 700 meter (2,300 feet) wide area, and the repair crews who worked on her. Eventually, the Soviet Navy dumped the damaged reactor into the Kara Sea.
The 2002 movie K-19: the Windowmaker [trailer shown above], which starred Harrison Ford and Liam Neeson, is based on the K-19 disaster.
4. The Goiânia Accident
In the 1980s, the Instituto Goiano de Radioterapia (IGR) was a private radiotherapy hospital in Goiânia, Brazil [pictured above]. When it moved to a new facility in 1985, a caesium-137-based therapy unit was left behind. The caesium-137 was encased in a shielding canister made of lead and steel.
Legal wrangling prevented the canister from being removed from the facility, and the court posted a security guard to protect the equipment. Unfortunately, that guard was nowhere to be found on September 13, 1987, when two men, Roberto dos Santos Alves and Wagner Mota Pereira, entered the facility and made off with the equipment, placing it in a wheelbarrow and taking it to Alves's house.
There, they began dismantling the equipment, and both immediately began to vomit. The next day, Pereira noticed a burn on his hand that required the amputation of several fingers.
Alves soldiered on, piercing the canister with a screwdriver. He noticed the blue light of Cherenkov radiation. Alves's arm ulcerated and had to be amputated, but before that, he sold the items to a scrapyard owned by Devair Alves Ferreira.
Fascinated by the blue glow being emitted, Ferreira carried the items into his house, and over the next three days, he invited his friends and family in to observe the blue glow.
Ferreira's brother brought some of the caesium to his house where he sprinkled it onto a floor. There, his six-year-old daughter, Leide das Neves Ferreira, sat down and ate a sandwich.
Eventually, Ferreira's wife took the caesium to a hospital, and news of the radioactive leak was broadcast on local media. 250 people were found to be contaminated by radiation, with 129 people having internal contamination.
Four people would die of radiation sickness including six-year-old Leide, Ferreira's wife Gabriela, 37, and two employees of Ferreira, Israel Baptista dos Santos, 22, and Admilson Alves de Souza, 18.
The Goiânia accident spread significant radioactive contamination throughout the Aeroporto, Central, and Ferroviários districts of Goiânia. Contaminated areas included Alves's house, Devair Ferreira's scrapyard which had extremely high levels of radiation, and his brother Ivo's house.
The "NATO Science for Peace and Security Series" bizarrely found radioactive contamination on three buses; 42 houses; fourteen cars; five pigs, and 50,000 rolls of toilet paper.
The Goiânia accident ranks as a number 5 on the International Nuclear and Radiological Event Scale. A 1990 film about the disaster won several awards at the 1990 Festival de Brasília film festival, and a 1994 episode of the TV series "Star Trek: The Next Generation," "Thine Own Self," was inspired by the Goiânia accident.
5. Chalk River Ontario, Canada Incident
On December 12, 1952, there was a power excursion and partial loss of coolant in the NRX reactor at the Chalk River nuclear laboratories [pictured above]. Because of mechanical problems, the control rods couldn't be lowered into the core, and the fuel rods overheated, resulting in a meltdown of the core.
Just like at Chernobyl, hydrogen gas caused an explosion that blew off the multi-ton reactor vessel seal. Also like at Chernobyl, 4,500 tons of radioactive water was found in the basement of the Chalk River reactor building.
During the accident, 10,000 curies or 370 TBq of radioactive material was released into the atmosphere.
Future U.S. president Jimmy Carter, then a U.S. Navy officer [pictured above], led a team of 13 U.S. Navy volunteers who helped in the cleanup of this disaster.
On the International Nuclear Event Scale, Chalk River is a 5, along with Goiânia, Three Mile Island, and Windscale.
Top image: Radiation danger warning sign at the Techa River, near the Mayak nuclear facility. Credit: Alla Slapovskaya & Alisa Nikulina/Wikimedia Commons.
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