Edwin Lau

Opinion | Our fragile oceans should not be a dumping ground for Fukushima’s radioactive waste water

Some scientists believe Japan’s treatment system for the radioactive waste water and its subsequent dilution in our oceans will make it safe, but many others are doubtful

Even small amounts of contaminants can accumulate in fish and human bodies. Importantly, we cannot afford to upset the fragile marine ecosystem

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Thousands of South Korean fishermen gather near the parliamentary building in Seoul on June 12 to protest against Japan’s waste water discharge plan. Photo: Xinhua

Edwin Lau

Published: 8:15am, 7 Jul 2023

The Japanese government is adamant about discharging treated radioactive waste water from the Fukushima Daiichi nuclear plant into the Pacific Ocean this summer despite strong opposition in many countries, including China and South Korea, as well as fishing communities in the region.

This week, Tokyo’s decision was reinforced by an International Atomic Energy Agency report concluding that the discharge plan complies with international safety standards.

The government says Japan’s advanced liquid processing system (ALPS) reduces the presence of 62 of the 64 hazardous radioactive elements in the waste water to within regulatory limits.

More than 1.3 million tonnes of this waste water is stored in some 1,000 stainless steel tanks at the site after the nuclear accident occurred in March 2011. Several of the radioactive elements contained in the waste water, such as carbon-14, strontium-90, caesium-137 and tritium, are considered to have potential effects on human health.

The half-life (or time taken for half the atomic nuclei to decay) of radionuclides varies. While some have decayed since 2011, carbon-14, for example, has a half-life of more than 5,000 years, which means it remains radioactive in the environment for many generations after us.

Tokyo says it is confident the ALPS can process most of the radionuclides in the waste water, except for two: carbon-14 and tritium. So the treated waste water still needs to be diluted before discharge, to reduce the concentration of these elements to acceptable levels.

A work ship is seen offshore where Tokyo Electric Power Company said it has installed the last piece of an undersea tunnel to be used to discharge the treated waste water, during a media tour to the Fukushima Daiichi nuclear power plant in northern Japan on June 26. Photo: AP