Millions of tons of highly contaminated water from Fukushima Daiichi being discharged into the Pacific Ocean not only poses a threat to humans and the environment, but also raises questions on how the decision by the Japanese government relates to international law.
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Duncan Currie |
Consequently, the Korean government has the legal right to oppose the discharging of radioactive water from the Fukushima Daiichi nuclear plant.
The discharge of radioactive materials into the marine environment from the nuclear plant will inevitably increase marine species' exposure to radioactivity, with the exact level of exposure depending on multiple variables. The concentrations in biota are of direct relevance to those who may consume them, including marine species, and ultimately, humans.
The one million tons of highly contaminated water stored in nearly 1000 tanks at the Fukushima Daiichi nuclear plant currently contain concentrations of radioactive tritium much higher than is permitted by Japanese regulation for discharge into the ocean. One principle concern is that the high relative biological effectiveness (RBE) of tritium's beta radiation, its ability to bind with cell constituents to form organically-bound tritium (OBT) and its short-range beta particle, mean that it can damage DNA.
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Shaun Burnie |
A further major problem is that the processing technology used at Fukushima Daiichi ― specifically the Advanced Liquid Processing System (ALPS) ― failed to operate effectively, and therefore around 800,000 tons of the water contains even higher amounts of radioactive material, including Sr-90. There are an estimated 30,000 Megabecquerels of Strontium90 in the storage tanks.
To give some perspective on this amount of strontium-90 ― it is what an average Pressurized Water Reactor would discharge in its liquid waste if it were to operate for 120,000 years. This is more than half the number of years humans have inhabited the earth. Even more threatening is that these discharges are only a small fraction of the radioactive inventory of what remains at the destroyed nuclear site. Most Strontium-90 still remains in the molten cores at the site ― an amount 17.3 million times more than would be released under the Japanese government's plans for the contaminated water. And there are many other radionuclides present in the contaminated water with even longer half-lives ― the time is takes for one-half of the radioactive material to decay ― including iodine-129, which has a half-life of 13 million years.
For South Korea, the impacts of this radiation exposure are of great importance to its fishing communities, the wider population and the government. The toxic cocktail of radionuclides from Fukushima Daiichi will rapidly disperse through the strong coastal currents along Japan's Pacific coast, and enter the East Sea via the East China Sea, including the waters of the Korean peninsula. We know this as a result of sea water sampling following the March 2011 nuclear disaster.
In addition to the requirements under the U.N. International Maritime Organization (IMO), Japan is required to comply with international law that prohibits significant trans-boundary environmental harm, both to the territory of other States and to areas beyond national jurisdiction. Before any discharge into the Pacific Ocean, Japan is required to conduct an Environment Impact Assessment under Article 206 of UNCLOS. International radio-protection principles require that a decision to increase radioactivity in the environment must be justified, and if there is a viable alternative ― in this case long-term storage ― it cannot be justified.
There never was a rationale for further, deliberate radioactive pollution of the marine environment from Fukushima Daiichi. In the interests of protection of that environment as well as public safety, and to ensure compliance with its international legal obligations, the only acceptable way forward for the Japanese government is to terminate its discharge plans. There is a clear alternative to discharging over one million tons of highly contaminated water into the environment, which is to securely store the water in robust tanks for the long term (hundreds of years). In parallel, the best available technology should be applied for further processing to remove all radionuclides.
Authors
Duncan Currie is a practicing international and environmental lawyer. He has practiced international law and environmental law for nearly thirty years, and over that time has advised NGOs, corporations and governments on a wide range of environmental issues including the law of the sea, nuclear and waste issues.
Shaun Burnie is a senior nuclear specialist with Greenpeace Germany, with much of his time based in Japan. He has worked on nuclear issues in Asia, the former Soviet Union, Europe, North and South America and the Middle East for 35 years. He worked against the operation of the TEPCO Fukushima Daiichi reactors since 1997.