Media reports say that Japan is to release treated radioactive water from the Fukushima nuclear plant into the sea. Some of the water was used as a coolant at the power station which was destroyed by a tsunami in 2011. Plant operator Tokyo Electric Power (Tepco) has processed the water through a filtration plant removing most of the radionuclides although there is no technology to separate tritium. Tepco has stored more than 1 million tonnes of this water in huge tanks at the site but is running out of space. The Japanese Government says no final decision has been made.