![]() ![]() ![]() Richmond is one of five scientists on a panel advising the Pacific Islands Forum, an intergovernmental organization made up of 18 Pacific nations including Australia, Fiji, Papua New Guinea and French Polynesia. “Have the people promoting this going forward - ALPS treatment of the water and then release into the ocean - demonstrated to our satisfaction that it will be safe for ocean health and human health?” asks Robert Richmond, marine biologist at the University of Hawaii at Manoa. The Philippine government has also called for Japan to reconsider releasing the water into the Pacific. Last year, the US National Association of Marine Laboratories in Herndon, Virginia, also voiced its opposition to the planned release, saying that there was “a lack of adequate and accurate scientific data supporting Japan’s assertion of safety”. Nations such as South Korea have expressed concern that the treated water could have unexplored impacts on the ocean environment, and a delegation from the country visited the Fukushima site in May. “The risk of another earthquake or a typhoon causing a leak of a tank is higher, and they’re running out of space.” Will radioactivity concentrate in fish? “The nearest Pacific island is about 2,000 kilometres away.” He argues that a greater risk is posed by keeping the treated water on-site. “I always hesitate to say zero, but close to zero,” he says. Jim Smith, an environmental scientist at the University of Portsmouth, UK, says the risk this poses to nations around the Pacific Ocean will probably be negligible. ![]() The carbon-14 in the tanks is currently at concentrations of around 2% of the upper limit set by regulations, TEPCO says, and this will reduce further with the seawater dilution that takes place before the water is discharged. The company suggests that the concentration of tritium will drop to background ocean levels within a few kilometres of the discharge site. TEPCO says that the resulting concentration of tritium is around 1,500 becquerels (a measure of the radioactivity of a substance) per litre - around one-seventh of the World Health Organization’s guidelines for tritium in drinking water. ![]() These limits are based on recommendations from the International Commission on Radiological Protection.īut that process does not remove carbon-14 and tritium, so the treated water needs to be diluted further to less than one part per 100 parts of seawater. The ALPS process removes enough of 62 of the 64 radionuclides to bring their concentration below Japan’s 2022 regulatory limits for water to be discharged into the environment. The plan for disposing of the radioactive waste created in the ALPS process will be “gradually revealed as the decommissioning process progresses”, according to communication the Permanent Mission of Japan to the International Organizations in Vienna sent to the International Atomic Energy Agency (IAEA). TEPCO says the water undergoes five processing stages of co-sedimentation, adsorption and physical filtration. The power-station operator, Tokyo Electric Power Company (TEPCO), so far has used what it describes as an advanced liquid-processing system (ALPS) to treat the water. The contaminated water has been collected, treated to reduce the radioactive content and stored in more than 1,000 stainless steel tanks at the site. But others take longer to decay carbon-14, for example, has a half-life of more than 5,000 years. Some of these radionuclides have a relatively short half-life and would already have decayed in the 12 years since the disaster. Of greatest concern are those that could pose a threat to human health: carbon-14, iodine-131, caesium-137, strontium-90, cobalt-60 and hydrogen-3, also known as tritium. Since then, more than 1.3 million cubic metres of seawater have been sprayed onto the damaged cores to keep them from overheating, contaminating the water with 64 radioactive elements, known as radionuclides. The power station exploded after a devastating earthquake and subsequent tsunami crippled the coastal plant, overheating the reactor cores. But just how safe is the water to the marine environment and humans across the Pacific region? How is the water contaminated? Starting sometime this year and continuing for the next 30 years, Japan will slowly release treated water stored in tanks at the site into the ocean through a pipeline extending one kilometre from the coast. Credit: Kimimasa Mayama/AFP via Gettyĭespite concerns from several nations and international groups, Japan is pressing ahead with plans to release water contaminated by the 2011 meltdown of the Fukushima Daiichi nuclear power plant into the Pacific Ocean. A TEPCO representative measures radiation levels around the treated water storage tanks in 2018. ![]()
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