Fukushima Daiichi Accident

The Fukushima Nuclear accident was a major nuclear accident at the Fukushima Daiichi Nuclear Power Plant in Ōkuma, Fukushima, Japan, which began on 11 March 2011.

The cause of the accident was the earthquake and the tsunami that occurred in the Pacific Ocean. The earthquake lasted approximately 6 minutes and brought a tsunami alongside. The earthquake, also known as the "Great East Japan Earthquake" was the most powerful earthquake ever recorded in Japan, and the fourth most powerful earthquake recorded in the world with a magnitude of 9,1 Mw. The earthquake triggered powerful tsunami waves that may have reached heights of up to 40.5 meters, and in the Sendai area, the waves traveled 10 kilometers inland. The catastrophe caused harm more than predicted when the nuclear accident was added. With the impact of the tsunami, the nuclear reactors at the plant suffered significant damage due to the loss of cooling.

The lack of cooling caused the reactor's cores to overheat. As the temperature inside the core continued to increase, the fuel rods began to melt, known as a "core meltdown". This meltdown happened in Units 1, 2, and 3. Compromised cores at the units ended with the release of radioactive materials. The overheated cores also caused risks of explosions.

This prediction of risk happened the following days. Units 1, 2, and 3 exploded due to hydrogen gas buildup. As you may guess, radioactive substances were leaked into the environment. With the ongoing situation, engineers worked to stabilize the reactors by pumping water into the cores.

After the accident, engineers had to come up with ideas to fix the situation.

To cool the reactors' cores, cooling fluids like seawater and fresh water were pumped into the reactors through pipes. Additionally, continuous monitoring and filtration systems were installed to prevent radioactive water from mixing with the ocean. The hydrogen gas buildup was still a risk. To mitigate this, they vented the gas safely from the reactors and mixed hydrogen with oxygen to prevent any kinds of explosions. a temporary concrete barrier and walls were constructed surrounding the area to limit the spreading.

In long-term solutions, they came up with the shutdown of the plant and entered the decommissioning phase. With the decommissioning, the plant would be monitored and safely refined to remove all the radioactive structure.

The accident resulted in the evacuation of thousands and long-lasting harm to the environment. But it also led to a global reassessment of nuclear energy and stricter rules. In conclusion, the Fukushima disaster had an effect on nuclear energy policies, and the event highlighted the shift to more sustainable energy resources.