Fukushima needs more than ice wall to reduce radioactive water

TOKYO: A government-commissioned group of experts concluded yesterday that a costly underground ice wall is only partially effective in reducing the ever-growing amount of contaminated water at Japan’s destroyed Fukushima nuclear plant, and other measures are needed.

The plant’s operator, Tokyo Electric Power Co, says the ice wall has helped reduce the radioactive water by half. The plant also pumps out several times as much groundwater before it reaches the tsunami-damaged reactors via a conventional drainage system using dozens of wells dug around the area.

The groundwater mixes with radioactive water leaking from the damaged reactors.

The panel agreed that the ice wall helps, but doesn’t solve the problem.

Members suggested extra measures be taken to minimise the inflow of rainwater and groundwater, such as repairing roofs and other damaged parts of the buildings.

The 1.5km coolant-filled underground structure was installed around the wrecked reactor buildings to create a frozen soil barrier and keep groundwater from flowing into the heavily radioactive area. The ice wall has been activated in phases since 2016. Frozen barriers are now deemed complete.

On Wednesday, Tepco said in addition to the 35 billion yen (R3.8bn) construction cost funded by taxpayers’ money, the ice wall needs more than 1 billion yen annually in operating and maintenance costs. Critics have been sceptical about the ice wall and suggested a greater use of wells – a standard groundwater drainage system – would be a cheaper and more proven option.

Officials aim to further reduce the amount of contaminated water in the reactor buildings before starting to remove melted fuel in 2021.