In the decade since the Fukushima Daiichi nuclear power plant disaster devastated the region, local fisheries have worked hard to win back consumer trust in their catch. As a confidence-building measure, all docked fish are routinely screened for radioactive caesium, and must meet standards more stringent than those in the EU, before they can be sold to market.
It was perhaps unsurprising, then, that when the Japanese Government announced in April that it will release around 1.25 million tonnes of water from the power plant site into the sea, those fishermen felt devastated once again.
Water has been steadily accumulating at the Fukushima site since it was evacuated 10 years ago. Currently, it’s stored in up to a thousand large tanks, but the government and Tepco [Tokyo Electric Power Company], the plant operator, say this strategy is not viable for the long-term future. Instead, the water must be released into the sea, possibly over a decade or so, though arrangements are yet to be confirmed.
The plans, which are expected to start in two years, have the backing of the International Atomic Energy Agency and the US Government. However, alongside local fishermen, China has called the move “extremely irresponsible” and South Korea and Taiwan are also strongly opposed.
Why is there so much water at Fukushima?
Water is an important part of all nuclear power plants because it’s used to cool the reactors’ hot radioactive cores. As a matter of routine, this water goes through a filtration process to reduce pollution to permitted levels and is then either stored in large tanks or released into nearby bodies of water.
When a core meltdown happens, radioactivity – primarily Caesium-137 and strontium – is released from the broken fuel pins into the cooling water, contaminating it. After this happened at Fukushima, a few cubic metres per hour were routinely added to the site to maintain cooling.
Furthermore, to stop any water from leaking out of the facility and into the sea, groundwater levels in the building were kept lower than outside, meaning the site is always gaining water. Hence why quantities increase by around 140 tonnes every day.
An advanced liquid processing system (ALPS) is used to remove Caesium, strontium, and other isotopes from the water; however, tritium, which cannot be chemically separated from water, still remains at low levels.
How safe is the water?
“I personally think [releasing the water] is the right thing to do,” says Lake Barrett, an independent consultant who has worked in the nuclear industry for five decades, including at Three Mile Island nuclear facility in the US. Barrett is also the former head of the US Department of Energy’s Office of Civilian Nuclear Waste Management and serves as a special advisor to the Japanese Government and Tepco’s president and board of directors.
“There is emotion because the water came from the Fukushima accident as opposed to normal operations. But don’t confuse emotion with technical reality: from a science, health, and environmental protection point of view, the radiation numbers and risks are very small,” he adds.
CANDU heavy water reactors used in China and Canada produce much more tritium than a light water reactor like Fukushima, says Barrett.
“During normal operations, Fukushima used to release tritium [into the ocean] and it was never a big issue. In fact, the amount of tritium set to be released in this new proposal is about the same as what happened prior to 2011,” he explains.
Dr Leslie Mabon, a senior lecturer in Marine Social Science at the Scottish Association for Marine Science-University of the Highlands and Islands, agreed that international scientific consensus says ‘if protocols are followed correctly’, the material contained in the water to be released is very unlikely to pose any risk of harm to people, fish, or the wider marine environment.
However, not all agree. Dr Paul Dorfman, a senior researcher at University College London and founder of the Nuclear Consulting Group, says in an email: “The issue is whether the concentration of radionuclides will damage the environment – and there is a complex debate around this.
“I think it’s true to say that marine species could have their DNA damaged through exposure to radionuclides in seawater, and a contaminated environment results in a contaminated food chain.”
Furthermore, writing in China Daily, Shaun Burnie, a senior nuclear specialist with Greenpeace East Asia, says that nearly 800,000 cubic meters of the water still contains high levels of radioactive strontium-90 and iodine-129. This is in addition to other radionuclides because the ALPS system failed to reduce radioactive elements, as claimed by the plant owner.
“It’s unclear whether they will be successful in doing so over the coming years,” he says.
Speaking off the record, another expert, who has visited Fukushima and Chernobyl, says that following the science, it would likely have been safe to release the water much sooner after the accident, rather than collecting it for 10 years.
“At first it looks like a sensible move, but you can’t, for decades, capture everything that flows into a site without thinking how you’re going to get rid of it.”
Responding to this suggestion, Barrett says: “In hindsight, could you have done that? Yes, it would have been legal and low risk, but I don’t think it would have been socially feasible.
“At Three Mile [where another nuclear accident occurred], it took decades of hard work by the owners to change the dialogue, to engage people with the facts but, in the end, the plant restarted and people didn’t want it to close when it became uneconomic to keep it running.”
After the Three Mile Island accident, due to public opposition, the water was evaporated, because the alternative was disposing of it directly into people’s drinking water.
This was easier to do because there were only 9,000 tonnes and the salt content was much lower. Doing the same for a million tonnes of briny water at Fukushima would likely be unfeasible. Storing it, Tepco says, is equally unsustainable because it will require ever more land and presents the risk of an uncontrolled spill.
Winning back trust
Releasing any contaminated water, however little, into the ocean is less than ideal, but as many scientists have pointed out, it doesn’t necessarily make it dangerous. But that doesn’t necessarily matter. As Mabon writes, reputational damage to Fukushima fisheries is the main cause for concern.
Public trust is hard to win back when it is lost and the handling of the fall-out from Fukushima, over the years, has not always been exemplary. Furthermore, the science is difficult to understand, and as Barrett says, “engineers generally aren’t the best communicators”.
Nevertheless, Japan has been ‘very transparent’ about its plans, he adds. Furthermore, before discharging any contaminated materials into the ocean, Japan is required to conduct an environmental impact assessment under Article 206 of the United Nations Convention on the Law of the Sea.
It’s also required to comply with international law that prohibits a country from causing significant trans-boundary environmental harm, both to the territory of other states and to areas beyond its national jurisdiction.
But this kind of monitoring at government level is not always reassuring to the public. At Three Mile Island, to win back the community’s trust, a citizens’ monitoring programme was started. This saw a local university train citizens to independently monitor the site and anti-nuclear campaigners were invited to review the procedures.
The Japanese Government and Tepco, who desperately need to gain public trust for their clean-up efforts, may need to consider new approaches, particularly ones that support the reputation of the fisheries of Fukushima.
“There’s definitely an opportunity for independent monitoring and other efforts,” concludes Barrett. “Ten-years from now, we may look back and people will say, ‘why was there such a fuss?’”