The number of storage tanks for contaminated water and other materials has continuously increased at Tokyo Electric Power Company Holdings, Inc.’s Fukushima No. 1 nuclear power plant, and space for still more tanks is approaching the limit.
Behind this is the fact that a way to get rid of treated water, or tritium water, has not been decided yet. The government and TEPCO will have to make a tough decision on disposal of tritium water down the road.
Water volume increasing
At the Fukushima No. 1 nuclear plant, groundwater and other water enters the reactor buildings that suffered meltdowns, where the water becomes contaminated. This produces about 160 tons of contaminated water per day. Purification devices remove many of the radioactive materials, but tritium — a radioactive isotope of hydrogen — cannot be removed for technical reasons. Thus, treated water that includes only tritium continues to increase.
Currently, the storage tanks have a capacity of about 1.13 million tons. About 1.07 million tons of that capacity is now in use, of which about 80 percent is for such treated water.
Space for tanks, which has been made by razing forests and other means, amounts to about 230,000 square meters — equivalent to almost 32 soccer fields. There is almost no more available vacant space.
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.”
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