Fukushima Radioactive Wastes

Japan is to release 1.2 million litres of cooling water contaminated with radioactive wastes into the ocean off the coast of Fukushima.

Fukushima Accident

The Fukushima Daiichi nuclear accident took place in March 2011 in Japan. It was triggered by the Tohoku earthquake and tsunami. It is one of the most significant nuclear accidents since the Chernobyl accident of 1986. The radiation level in the adjoining sea went up to levels millions of magnitude higher than the government prescribed limit of 100 Becquerel.

Contaminated Water

The water from the destroyed power plant is contaminated with radioactive wastes. It is being stored in huge tanks. There are about 900 such tanks at the Fukushima site. These tanks currently hold about 1.2 million tonnes of contaminated water that was collected from cooling pipes (for cooling the fuel cores). The facility will run out of storage space by 2022.

Disposal

The current debate is about how the contaminated water can be disposed of. The main choices have been either to release the water into the Pacific Ocean and let the water dilute the contamination or to let the water evaporate. Also, the water is to be filtered to remove the radioactive contaminants except tritium.