In the eight years since the, Japan's Tokyo Electric Power Company (Tepco) has collected more than , and it's running out of space to store it all. On Tuesday, the country's environment minister offered a worrying solution to the problem -- dumping that water into the Pacific Ocean.
"The only option will be to drain it into the sea and dilute it," Yoshiaki Harada told reporters in Tokyo, according to Reuters. "The whole of the government will discuss this, but I would like to offer my simple opinion."
Japan's chief cabinet secretary, Yoshihide Suga, separately emphasized that the government hadn't settled on a course of action, CNN reported.
A massive earthquake on March 11, 2011, caused three reactors at the Fukushima Daiichi nuclear plant to melt down, releasing radiation into the air and forcing the evacuation of more than 160,000 people from the area. Over the last eight years, Tepco has had to continually use fresh water to cool the reactors.
But the question about what to do with the increasing amount of water was always going to come to a head. Tepco has been storing contaminated water from the reactors in 900 tanks on the grounds at Daiichi, but a spokesperson told CNET's Roger Cheng last year that it expects to run out of space in the 37.7-million-square-foot facility sometime in 2020.
"We're conscious of the fact that we can't keep storing more and more water," Kenji Abe said through an interpreter.
Tepco has worked on several solutions to decrease the level of contaminated water generated by the facility. The company has switched from tanks sealed with bolts to welded tanks, which offer greater storage capacity and less risk of leaks. There's a steel wall by the water to keep the contaminants from flowing into the ocean. Tepco has also covered 96 percent of the surface of most of the facility with concrete, preventing rainwater from seeping in.
An impermeable ice wall is currently keeping radioactive contaminants from the melted-down reactors from spilling into the water, as robots.
Tepco has worked to remove the contaminants from the water, and have managed to remove 62 out of the 63 radioactive elements out. But the last, tritium, has proven difficult because it bonds to water molecules.
While nuclear industry observers note that other plants around the world discharge water with tritium, there's a particular sensitivity with Fukushima. Organizations such as Greenpeace have called for Tepco to keep storing the water, noting that much of the early batches of treated water far exceed safety limits for radioactive elements.
The Japanese Ministry of the Environment didn't immediately respond to a request for comment.
First published at 3:28 a.m. PT.
Updated at 3:55 a.m. PT and 6:44 a.m.: Adds more detail.