Scientists at the Fukushima Daiichi nuclear plant in Japan have declared a state of emergency because one of the reactors is on the verge of collapse and could fall into the ocean. This event has once again put the possible environmental consequences in the spotlight after several years of complex management of the aftermath of the nuclear accident that occurred in 2011.
Lethal radiation levels have been detected around reactor 2, attributed to a leak caused by melted nuclear fuel. The discovery revives the nightmare of Fukushima and is a reminder of the challenges of decommissioning a severely damaged nuclear power plant. LAST MINUTE: Non-gravity explosion at a nuclear power plant in France
Radiation levels in reactor 2
In the latest measurements reported by the Tokyo Electric Power Company (TEPCO), alarming levels of radiation were detected inside reactor 2 of the Fukushima nuclear power plant. Records indicate that values ​​of 530 sieverts per hour, which represents a direct threat to human life.
To put this into context, a dose of just 8 sieverts is considered sufficient to cause certain death in a human being. Therefore, the magnitude of 530 sieverts per hour is extremely dangerous and requires specialized handling with the strictest safety measures.
Impact of the discharge of contaminated water
In the summer of 2023, Japan made the controversial decision to begin dumping a significant amount of contaminated and treated water from the Fukushima plant into the Pacific Ocean. This action has generated strong opinions both inside and outside Japan. Tokyo Electric Power Company (TEPCO) initiated this process, arguing that the discharge is carried out under strict controls to ensure environmental safety, and that it does not pose an immediate risk due to the dilution and treatment that the water has received.
The International Atomic Energy Agency (IAEA) has backed the move, saying tritium levels in treated water are far below globally accepted limits. However, the move has sparked protests, especially among neighbouring countries such as China and South Korea, which have sharply criticised the Japanese policy, accusing Japan of acting irresponsibly.
Hole in the pressure vessel of reactor 2
During inspections at reactor 2, a leak was discovered one square meter hole below the pressure vessel. This damage is the result of nuclear fuel melting during the 2011 accident. Some of the molten fuel appears to have penetrated through the reactor's metal structure. TEPCO has said that the remains of the molten nuclear fuel were located at the bottom of the vessel, just above the hole. Because of this, the risk of radioactive material being released into the ocean has increased considerably, justifying the declaration of an emergency.
This discovery was made possible by the use of a camera probe remote-controlled device that was inserted into the reactor. This technology allows reaching areas inaccessible to humans due to the lethal levels of radiation present. However, the equipment used faces serious challenges, as even the robots have been damaged due to extreme radiation, which makes inspection tasks difficult.
Long-term decommissioning plan
The process of decommissioning the Fukushima plant remains a monumental challenge. Recent estimates suggest the work could take between 30 and 40 years. Among the main hurdles are the safe removal of radioactive debris and the handling of trapped nuclear fuel. The task of dismantling the reactor is complicated by the extremely high residual radiation, which requires the continuous use of specialized robots. Despite technological advances, drones and robots recently sent to reactor 1 also failed to complete their mission due to technical glitches.
The radioactive water spill and the international reaction
Since the process of dumping treated water into the ocean began, several countries have raised their voices. Environmental groups, as well as China and South Korea, have expressed concerns about the long-term effects on marine wildlife and the potential impact on local economies such as fisheries. China in particular has been vocal, imposing bans on the import of Japanese fishery products, citing concerns about food safety. Japan has defended its actions, saying that the dilution of treated water ensures radiation levels will be well below international standards.
- Generation of new nuclear fuelThe plant continues to generate about 90 tons of radioactive water daily.
- Advanced Liquid Processing System: The water has been treated to remove most of the radioactive isotopes.
Lessons learned and the future of the plant
The Fukushima accident has provided important lessons for other nuclear-powered nations. Globally, safety agencies have tightened their protocols and requirements, while governments continue to monitor progress at the Fukushima plant. The IAEA has sent multiple missions to inspect the progress of the decommissioning and management of radioactive water. However, complete decommissioning of the plant remains a task that requires not only time but also continued technological advances, as radiation limits human access to the most critical areas.
The challenge of handling and storing nuclear waste remains. So far, there is no definitive solution for the long-term storage of the most dangerous waste. However, the TEPCO team has made significant progress in monitoring affected areas and remediating the site, although serious complications remain. The events at Fukushima remain one of the greatest reminders of the importance of nuclear safety and the need for comprehensive plans that take into account long-term environmental protection. This process not only affects Japan, but also provides enormous learning for future generations of scientists, engineers and regulators focused on the safe use of nuclear energy.