The Nuclear Regulation Authority (NRA) of Japan has given formal approval to the plan of the Tokyo Electric Power Company (Tepco) to discharge into the sea treated water from the disabled and deactivated Fukushima Daiichi nuclear power plant (NPP). The operational reactors at the plant had been wrecked by the devastating tsunami which hit north-eastern Japan, following a massive undersea earthquake, in 2011. Following the consequent meltdowns of the three reactors, water was used to cool the melted nuclear fuel. That, and other contaminated water, has been stored in a tank farm, containing some 1 000 tanks, constructed on the NPP site. The water is being treated, using an Advanced Liquid Processing System (ALPS). This removes all the radioactive contamination, except for tritium (which is a radioactive isotope of hydrogen).
