On April 25, 1986, Power Station 4 at the Chernobyl Nuclear Power Plant began scheduled periodic maintenance. However, due to successive operational errors, the reactor at Station 4 was in a very unstable state.April 26, 1986 was the day when tragedy began for the Chernobyl nuclear power plant. At 1:23 a.m., two dull explosions broke the surrounding silence. With the explosions, a column of fire more than 30 meters high lifted off the reactor's shell and shot into the sky. The entire protective structure and various equipment of the reactor were lifted up, and flames as high as 2,000 degrees Celsius engulfed the engine room and melted the thick steel frame. Water vapor and dust carrying highly radioactive substances rose and filled the air with smoke, obscuring the sky. Although firefighters arrived at the scene six minutes after the accident, the intense heat radiation made it difficult to get close, and helicopters had to be used to drop sandbags containing lead (Pb) and boron (B) down from the air to seal the reactor and stop the radioactive material from leaking out.
The damage caused by the accident at the Chernobyl nuclear power plant was tragic, with the concentration of nuclear fuel leaking at the time of the explosion as high as 60 percent, and until the reactor was sealed 10 days and nights after the accident, radioactive elements had been released in excessive quantities. The neighborhood was hastily evacuated only three days after the accident, but those three days had already left many people contaminated with radioactive materials. Two people died instantly in this accident, and by 1992, more than 700O people had died from the nuclear contamination of this accident. The radioactive contamination caused by the accident spread over 150,000 square kilometers of the former Soviet Union, where 694.5 million people lived. As a result of the accident, a 30-kilometer area around the nuclear power plant was designated as a quarantine zone, nearby residents were evacuated, crops were completely buried, and trees within 7 kilometers of the plant gradually died. For the next half century, farming and grazing will not be allowed within 10 kilometers, and milk production will be banned within 100 kilometers for 10 years. Not only that, but the whole of Europe was shrouded in the shadow of nuclear contamination due to the spread of radioactive fallout. Extraordinary levels of radioactive fallout were detected in neighboring countries, resulting in huge losses in the production of food, vegetables, and dairy products. The mental and psychological disturbances and fears caused by the nuclear contamination are even more incalculable. In the seven years following the accident, 7,000 cleanup workers died, one-third of whom committed suicide. Forty percent of the workers who participated in the medical rescue suffered from mental illness or permanent memory loss. To this day, 55,000 of the 834,000 people who participated in the rescue effort have been killed, 50,000 have been disabled, and more than 300,000 have died from radiation injuries.
While nuclear power is the newest, cleanest, and lowest-cost source of electricity, nuclear contamination due to possible nuclear leaks has brought unprecedented disasters to mankind. To date, in addition to the Chernobyl accident, nuclear leakage accidents have occurred at the Sellafield nuclear power plant in northern England, the Brownsfield nuclear power plant in the United States, and the Three Circles nuclear power plant. In addition to these, there have been a number of nuclear submarine accidents in the world's waters. These scattered on land, in the air and sleeping on the seabed of the nuclear pollution to human beings and the environment brought about by the harm far beyond the reported figures can be drawn to a conclusion, because the latent period of nuclear radiation up to several decades.