A solid step has been taken toward the decommissioning of the reactors at Tokyo Electric Power Co.’s Fukushima No. 1 nuclear power plant.
The Fukushima Prefectural Federation of Fisheries Cooperative Associations has approved TEPCO’s plan to release water into the ocean after it has been decontaminated.
Under the plan, TEPCO will pump up water from wells, called subdrains, around reactor buildings at the plant. This water will then be treated and discharged into the sea. There are expectations that this will reduce the volume of contaminated water generated when groundwater accumulates inside buildings wrecked by the March 11, 2011, earthquake and tsunami.
Regarding water quality management, TEPCO plans to set a stringent goal of cleaning the water to a level that exceeds international standards for drinking water. It is conducting water purification tests using a special-purpose treatment system. We hope the utility will carefully explain the system to clear up any anxiety felt by the public.
Initially, the volume of groundwater seeping into the buildings at the nuclear plant reached about 400 tons a day.
Since May 2014, TEPCO has been pumping up groundwater from other wells on the hill near the plant and releasing it into the sea before it flows into the buildings and becomes contaminated. This process has reduced the daily volume of water entering the buildings to about 300 tons a day.
TEPCO believes realization of the plan to pump water from the subdrains and discharging it into the sea after treatment could halve the volume of water entering the wrecked buildings.
However, even after treated water is discharged into the sea, contaminated water will continue to accumulate. A veritable forest of about 950 large tanks, which combined hold about 690,000 tons of water, already stands within the plant’s premises.
At some point, discharging this water into the sea also will need to be considered.
This editorial appeared in The Japan News/Yomiuri Shimbun.