Isabella Notarpietro | Climate Change Fellow
In 2011, the world looked on in horror as a tsunami pummelled Japan’s Fukushima Daichi reactor, causing three of the four reactors to meltdown and release huge amounts of radiation. The incident triggered a major shift in public opinion on nuclear power globally, prompting several countries to announce plans to phase out nuclear power and a four per cent drop in nuclear-generated electricity in 2012. Since then, however, nuclear generation capacity has been steadily increasing around the world, with nuclear considered a promising low-carbon energy source. Indeed, in Australia, the recent AUKUS deal has prompted calls for the long-standing nuclear ban to be overturned.
Fukushima provides a sobering reminder that nuclear power differs greatly from other low-carbon energy sources. In 2021, Japan announced its intention to release over 500 Olympic swimming pools worth of radioactive water from Fukushima into the ocean. As the use of nuclear power continues to grow, the international, intergenerational, and interspecies impact of this waste stream must be addressed and integrated into sustainable energy policies.
Fukushima—Plans and Pushback
The Fukushima wastewater has two primary sources. The first is water produced from cooling the reactor cores in the aftermath of the incident. The other is contaminated groundwater and rainwater. This wastewater has been treated via a multi-nuclide removal facility (called ALPS) and stored in over 1,000 on-site storage tanks. In 2019, the plant’s operator TEPCO announced they were running out of storage space. With the Japanese government unwilling to extend the site boundary, in 2021 TEPCO received government approval to discharge the wastewater into the Pacific Ocean.
The proposal has raised significant concerns among neighbouring countries. At the 2022/23 Pacific Islands Forum (PIF), Pacific leaders urged Japan to delay the release until the environmental and human health impacts on oceanic communities could be ascertained. Concerns were raised about high concentrations of tritium–a radioactive form of hydrogen which cannot be removed via ALPS–and the reliability of radioisotope monitoring data. An expert panel to the PIF concluded that the “present plan does not provide the assurance of safety needed for people’s health or for sound stewardship of the ocean”. Echoing these concerns, China warned Japan to postpone its plans “until full consultation and agreement is reached with neighbouring countries.”
Japan has rebuffed these concerns with modelling that indicates dilution will lower radiation levels below regulatory standards. It asserted that tritium has “little impact on the human body” and emphasised that the plans align with the safety standards set by the International Atomic Energy Agency.
The issue also speaks to the transgenerational impacts of nuclear power. TEPCO is proposing to release the water over 40 years. This timeline could be extended by “decades longer” when considering the additional water that will accumulate over the treatment period, thereby shifting the burden of managing wastewater disposal to future generations. Moreover, despite tritium (and other radionuclides potentially present in the wastewater) having relatively short half-lives compared to other radioactive species, they can last for decades in the environment, and the effects of long-term exposure to radionuclides are not fully understood.
Finally, the Fukushima proposal raises concerns over interspecies justice and the rights of the more-than-human world. Acceptable radioactive dosage limits are based on human exposure thresholds. There is substantial evidence that both radioactive dosage thresholds and radionuclide accumulation patterns differ between species. These effects can compound throughout the food chain, with one study finding concentrations of radioactive caesium three to four times higher in seals compared to the fish they ate, and 300 times greater than the seawater. The reality is that the full effects of different radioactivity dosages on many marine species are still unknown, particularly over long time horizons.
A One-off Case?
The Fukushima case is unique; the vast majority of nuclear reactors will not melt down and produce millions of tonnes of radioactive water. The production of nuclear wastewater is, however, a fundamental aspect of nuclear power generation which has historically been managed via dilution.
Nuclear power plants require large quantities of cooling water. While this water can be reused, eventually some of it must be released as liquid effluents. In most nuclear plants, the liquid effluents are treated and then released to local waterways. France’s largest nuclear power plant, La Hague, “legally discharges 33 million litres of radioactive liquid into the sea each year” according to an ecologist. While these discharges are carefully monitored to ensure concentrations are below safety thresholds, research indicates that prolonged exposure to radionuclides can result in DNA damage to marine species. Clearly, the consequences of nuclear wastewater are not isolated to accident sites like Fukushima.
The Need for Change
For many decades, waste management was governed by the mantra “dilution is the solution to pollution.” Fukushima highlights how deeply embedded this approach still is in the nuclear industry.
Fortunately, there are other solutions. The PIF expert panel outlined three alternative options to ocean discharge: storage in more permanent tanks to allow radionuclide decay; bioremediation; and the use of the water to make concrete. While there are other risks inherent to these methods, plus economic and technological barriers to implementation, they deserve to be properly evaluated. Industry-wide, there are now also a large number of chemical, physical, and biological methods for treating nuclear wastewater. Though many are yet to be proven at scale and come with significant economic costs, by necessity, they must be investigated further.
In 2022, the International Energy Agency noted that “nuclear power has the potential to play a significant role in helping countries to securely transition to energy systems dominated by renewables”. The trend of increasing nuclear power is therefore unlikely to abate. As the Fukushima debacle highlights, however, nuclear energy is not like other low carbon energy sources; it intrinsically carries a host of unique risks. We must stop conflating nuclear power with other low carbon energy sources and seriously consider whether these risks can be justified. For facilities which already exist, the nuclear industry needs to start taking the management of radioactive wastewater seriously. This means shifting away from archaic “dilution is the solution” approaches and instead holding generators to account for their wastewater treatment. Given the current barriers, effectively doing so necessitates significant additional investments to realise industrial-scale radioactive wastewater treatment as well as much better consultation with impacted communities.