Our environment correspondent Matt McGrath assesses the ongoing efforts to deal with contaminated water at the damaged Fukushima nuclear power plant in Japan. It has been revealed that some of the storage facilities used in the clean-up have been leaking highly radioactive water.
This isn't the first water leak at the plant. What is going on?
The ongoing problem with water seems to be coming, in the main, from poorly constructed storage tanks.
Tepco, the company that operates Fukushima, is using huge volumes of water every day to cool the reactors that once generated electricity at the plant.
When the water comes in contact with fuel rods at the heart of the reactors, it becomes highly radioactive and has to be stored in large containers on the site where the water is then processed to remove some of the most dangerous elements.
Every day, the company has an extra 400 tonnes of irradiated water to store. This is roughly a 10th of an Olympic-sized swimming pool.
By Matt McGrath
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