Fukushima nuclear tragedy hovers over Japan and region 11 years after tsunami and accident

The International Atomic Energy Agency set up a task force last year to oversee proper disposal of the wastewater. The task force consists of staff members from across various departments and laboratories of the IAEA, and 11 internationally recognized experts with diverse backgrounds from Argentina, Australia, Canada, China, France, the Marshall Islands, the Republic of Korea, the Russian Federation, the United Kingdom, the United States and Vietnam.

Professor Brendan Kennedy, from the School of Chemistry at the University of Sydney, said the water used to cool the reactors has an excess of tritium, a radioactive form of hydrogen. "Tritium is all around us, but now we have an excess. The question is what to do with it," Kennedy said.

Associate professor Nigel Marks of the physics and astronomy department at Curtin University, Western Australia, said eleven years after the disaster, the reactors at Fukushima are still being cooled down.

"And this will continue for many years to come. A vast number of large storage tanks have been built on the site, but space is rapidly running out," Marks said.

"This is why the Japanese govt announced last year that treated wastewater would be released into the ocean."

He said the vast majority of toxic elements could have been removed from the wastewater.

"But one element remains – tritium, a mildly radioactive form of hydrogen that is impossible to separate from water on an industrial scale," Marks said.