The operator of the crippled Fukushima Daiichi nuclear power plant on Tuesday completed its seventh round of treated radioactive water discharge into the ocean.
Tokyo Electric Power Company Holdings Inc. released around 7,800 tons of water in the latest round, which started on June 28, with the operator saying no abnormal tritium levels were detected in nearby waters.
While the latest water release is the seventh overall, it marked the third of seven discharge rounds planned for fiscal 2024.
Prior to discharge, water used to cool melted fuel at the plant is passed through an advanced liquid processing system that removes most radionuclides apart from tritium.
TEPCO detected 18 becquerels of tritium per liter from seawater sampled from the facility's outlet, below its own limit of 700 becquerels required for the discharge to be halted and far under the World Health Organization's limit of 10,000 becquerels for drinking water.
TEPCO plans to discharge about 54,600 tons over the course of seven rounds in fiscal 2024. The first round of the water release went ahead in August 2023 as a key step in decommissioning the Fukushima Daiichi plant, which suffered fuel meltdowns in three reactors following a massive earthquake and tsunami in 2011.