Build-up of contaminated water from wrecked nuclear plant has been sticking point in clean-up likely to take decades //

In 2018, Tokyo Electric apologised after admitting its filtration systems had not removed all dangerous material from the water, and the site is running out of room for storage tanks.

But it plans to remove all radioactive particles from the water except tritium, an isotope of hydrogen that is hard to separate and is considered to be relatively harmless.

“Compared to evaporation, ocean release can be done more securely,” the committee said, pointing to common practice around the world where normally operating nuclear stations release water that contains tritium into the sea. //

Tokyo Electric, or Tepco, has collected nearly 1.2m tonnes of contaminated water from the cooling pipes used to keep fuel cores from melting since the plant was crippled by an earthquake and tsunami in 2011. The water is stored in huge tanks that crowd the site.