Warnings raised about tritium levels at Chinese nuclear plants

Japanese government say planned discharge of tritium tainted wastewater from Fukushima will be 6.5 times less than China's plants

Jun. 30, 2023 09:18

The Fukushima Daiichi Nuclear Power Plant.

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TAIPEI (Taiwan News) — Chinese nuclear plants have released water with tritium levels 6.5 times higher than the intended discharge of wastewater from Fukushima, a Japanese government document shows.

The document, obtained by Yomiuri Shimbun and published on June 23, reveals the tritium release from four Chinese nuclear power plants in 2020 and 2021. It also compares them with the planned and pre-2011 release from Tokyo Electric Power Company Holdings (TEPCO), Fukushima No. 1 nuclear power plant.

The release of tritium-contaminated water has sparked concerns on the grounds it can cause serious environmental damage. However, China has not provided any agreements or explanations regarding the tritium release from its nuclear power plants, a Japanese government official told the Yomiuri Shimbun.

According to the document, the tritium releases from the four Chinese nuclear power plants were:

• Qinshan III phase nuclear power plant: Released approximately 143 trillion becquerels of tritium in 2020

• Yangjiang nuclear power plant: Released 112 trillion becquerels of tritium in 2021

• Ningde nuclear power plant: Released 102 trillion becquerels of tritium in 2021

• Hongyanhe nuclear power plant: Released 90 trillion becquerels of tritium in 2021

Japanese government graphic on TEPCO's discharge. (Taiwan News collage)

In comparison, Tokyo Electric Power Company (TEPCO) plans to release less than 22 trillion becquerels of tritium from Fukushima No. 1 nuclear power plant. Before the 2011 meltdown, the plant released approximately 2.2 trillion becquerels of tritium.

TEPCO said the concentration of tritium in the treated water is approximately 1,500 becquerels per liter, which is about one-seventh of the World Health Organization's guideline limits for tritium in drinking water. It expects tritium levels to normalize near the discharge site, per Nature.

TEPCO has also conducted tests comparing the health of fish raised in diluted treated water to those raised in untreated seawater. The tests have shown that tritium concentrations in marine organisms exposed to ALPS-treated water stabilize and do not exceed natural levels, as reported by Nature.

However, some experts have raised safety concerns about the release of treated water into the ocean. Professor Robert Richmond from the University of Hawaii said that tritium can concentrate in the food web and damage DNA. He also questions the efficacy of dilution as a pollution solution.

Professor David Krawczyk from the University of Auckland said tritium is naturally produced and already present in significant quantities in the world's oceans. He says that Fukushima's tritium discharge is the least bad option among all available alternatives.

He also warned against the risks associated with keeping the treated water on-site, citing the potential for increased leaks from tanks during earthquakes or typhoons.

In terms of health concerns, carbon-14 raises particular alarm among radionuclides with short half-lives, per Nature. Carbon-14 has a long half-life of over 5,000 years and can enter the food chain.

To address these concerns, TEPCO said that the carbon-14 concentration in storage tanks currently remains well below the regulatory limit of 2%, with further reduction expected through seawater dilution before the planned release.

Professor Krawczyk said that tritium and carbon-14 should not raise significant concerns, as they are present in our daily lives through consumption and inhalation. He highlighted the dilution factor involved before the water is released, which effectively lowers concentration levels.

He also expressed concern about the products of nuclear fission, such as cesium and strontium, which are derived from nuclear fission or weapons testing. He said they are very nasty and can accumulate in bones, teeth, and thyroid glands.

TEPCO said that its Advanced Liquid-Processing System (ALPS) effectively reduces the concentration of 62 out of 64 radionuclides, aligning with Japan's water discharge limits and international recommendations, as reported by Nature. However, the Associated Press said that approximately 70% of the ALPS-treated water still contains cesium and other detectable levels of radionuclides.

As Japan prepares to discharge the treated water, Prime Minister Kishida Fumio is scheduled to meet with International Atomic Energy Agency (IAEA) Director-General Rafael Grossi on July 4, per Japan Times. Grossi is expected to present a comprehensive report compiled by the IAEA, addressing the safety aspects of water discharge.

The Fukushima Daiichi nuclear power plant suffered a devastating meltdown in 2011 following a powerful earthquake and tsunami. Since then, approximately 1.3 million tonnes of water have accumulated on-site, serving to cool the damaged reactor cores.

The release of the treated water is planned for summer 2023, and the aim is to facilitate the decommissioning of the plant by 2051. However, experts cast doubts on achieving the ambitious 2051 goal, given the formidable task of removing all debris within the designated timeframe.