The Tokyo Electric Power Company is running out of container space to store water contaminated by tritium outside the Fukushima No. 1 nuclear power plant, and it's also running out of room for building more tanks, according to Yomiuri Shimbum, a Japanese newspaper, which is creating an intractable problem for the utility, which has been tasked with supervising the cleanup of Fukushima.
The Japanese government has been desperately trying to accelerate the cleanup ahead of the upcoming 2020 Olympic Games in Tokyo - and it's a miracle it hasn't run into this issue sooner. TEPCO is still struggling with how to dispose of the tritium-tainted water. Options discussed have included dumping it into the ocean, but that proposal has angered local fishing communities.
At some point, TEPCO and the government will need to make a difficult decision. Until then, ground water will continue to seep into the ruined reactor, where it becomes contaminated. Afterward, TEPCO can treat the contaminated water to purify it, but they can't remove the tritium, which is why the supply of water contaminated with tritium continues to grow.
As one government official pointed out, Japan can't simply store the radioactive water forever. As of now, the company should be able to store water until 2020.
Efforts have been made to increase storage capacity by constructing bigger tanks when the time comes for replacing the current ones. But a senior official of the Economy, Trade and Industry Ministry said, "Operation of tanks is close to its capacity."
TEPCO plans to secure 1.37 million tons of storage capacity by the end of 2020, but it has not yet decided on a plan for after 2021. Akira Ono, chief decommissioning officer of TEPCO, said, "It is impossible to continue to store [treated water] forever."
But after that, Tepco is either going to need to start releasing the tritium water into the ocean (something that has been done by many power plants, but is politically popular in Japan) or find another solution. In fact, an average of 380 trillion becquerels had been annually released into the sea across Japan during the five years before the accident. If the water from Fukushima is diluted to the point that tritium content is only 1 million becquerels per liter, which is more than 10 times higher than the national average for sea release. But if it's diluted, it can eventually be released. However, an industry report has determined that sea release would be the safest and most efficient option.
Regarding disposal methods for the treated water, the industry ministry’s working group compiled a report in June 2016 that said that the method of release into the sea is the cheapest and quickest among five ideas it examined. The ideas were (1) release into the sea, (2) release by evaporation, (3) release after electrolysis, (4) burial underground and...