Fukushima: Why is Japan releasing water and is it safe?
Japan began pumping more than a million metric tons of treated radioactive water from the destroyed Fukushima Daiichi nuclear power plant on Thursday, a process that will take decades to complete.
The water was distilled after being contaminated from contact with fuel rods at the reactor, destroyed in a 2011 earthquake and tsunami.
Tanks on the site hold about 1.3 million tonnes of the water — enough to fill 500 Olympic-sized swimming pools.
WHAT IS JAPAN'S WATER RELEASE PLAN?
The utility responsible for the plant, Tokyo Electric Power (Tepco), has been filtering the contaminated water to remove isotopes, leaving only tritium, a radioactive isotope of hydrogen that is hard to separate. Tepco will dilute the water until tritium levels fall below regulatory limits before pumping it into the sea from the site on the coast north of Tokyo.
Water containing tritium is routinely released from nuclear plants around the world, and regulatory authorities support dealing with the Fukushima water in this way.
Tritium is considered to be relatively harmless because its radiation is not energetic enough to penetrate human skin.
When ingested at levels above those in the released water it can raise cancer risks, a Scientific American article said in 2014.
The water disposal will take decades to complete alongside the planned decommissioning of the plant.
IS THE WATER SAFE?
Japan and scientific organisations say the water is safe, but environmental activists argue that all possible impacts have not been studied. Japan says it needs to start releasing the water as storage tanks are full.
The International Atomic Energy Agency (IAEA), the U.N.
