Fukushima’s Dilemma

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A roadblock is removed near JR Yonomori Station in Tomioka, Fukushima Prefecture, in March after an evacuation order for the area was lifted.

photo：Yomiuri Shimbun file

Government grants of up to ¥2 million will be provided next fiscal year to people who move to one of 12 municipalities surrounding the Fukushima No. 1 nuclear plant, where meltdowns occurred following the 2011 Great East Japan Earthquake, according to sources.

Japan government planning grants for

those willing to reside in Fukushima Prefecture

photo：CBC

The 12 municipalities — all in Fukushima Prefecture — are Futaba, Okuma, Tomioka, Namie, Iitate, Kawamata, Minami-Soma, Katsurao, Naraha, Kawauchi, Tamura and Hirono. Next March will mark 10 years since the nuclear accident at the plant operated by Tokyo Electric Power Company Holdings, Inc., but the population of these municipalities still hovers around 20% of the number in the basic resident register.

Evacuation orders were issued at the time of the accident but have since been gradually lifted.

The government aims to promote the reconstruction and revitalization of the area by not only encouraging evacuees to return, but also by getting people from outside the area to move in.

The grants will be offered, likely next summer or later, to people who did not live in the 12 municipalities at the time of the 2011 accident.

A family moving in from outside Fukushima Prefecture will receive ¥2 million, and a family from within the prefecture will be offered ¥1.2 million. For a single-person household, the grant will be ¥1.2 million for a newcomer to the prefecture and ¥800,000 for someone from Fukushima Prefecture.

Recipients would be required to live in the region for at least five years and to have a job. People who live in the 12 municipalities and telework for firms outside the region will also be eligible for a grant.

photo：dw.com

Those who start businesses within five years of moving to one of the municipalities will also receive three-quarters of the necessary expenses, with a maximum limit set at ¥4 million.

The grants will be paid from resources including subsidies to accelerate the revitalization of Fukushima Prefecture, provided to the Fukushima prefectural government and the 12 local governments by the Reconstruction Agency.

What to do with hundreds of thousands of tonnes of contaminated water?

The word “Fukushima” has become known globally as shorthand for a nuclear disaster that happened at the Fukushima Daiichi Nuclear Power Plant on the coast of Japan in March 2011. The disaster at the plant—about three hours’ drive north of Tokyo on the shore of the Pacific Ocean—began with a Magnitude 9.0 earthquake and tsunami that flooded critical control equipment and triggered a meltdown. For nearly a decade, the plant’s workers have cooled the wreckage with water. Now the Tokyo Electric Power Company (TEPCO), the power plant’s owner, is facing a new problem: what to do with radioactive water piling up at the site.

Each reactor encloses rods of uranium pellets. Uranium is naturally radioactive and undergoes a process called fission—its atoms decay, or split, at a predictable rate, emitting neutrons and heat. In the reactor fuel, this natural ability is harnessed—neutrons collide with other uranium atoms and split them apart in a chain reaction. The resulting heat is used to boil water, which drives steam turbines and generates electricity. Nuclear reactors control fission rates by surrounding the fuel rods with “control rods” that absorb extra neutrons. To keep the fuel cooled and avoid overheating and meltdown, it is immersed in water. Before the quake, three of Fukushima’s six nuclear reactors were in use and operating smoothly to generate electricity.

Tanks containing radioactive water are seen at the Fukushima No. 1 nuclear power plant grounds in August.

photo：The Japan Times

Then the earthquake struck. The plant’s reactors withstood the damage but lost power. The subsequent tsunami flooded critical operating equipment, and the cooling systems stopped working, triggering a meltdown. Workers eventually contained the meltdown, but they’ve had to keep the smoldering site cool for nearly 10 years, pumping water into the ruined buildings. Now the plant has a huge volume of used radioactive water, and nowhere to put it.

We’ve unpacked this coastal conundrum with the help of marine chemist and oceanographer Jay Cullen at the University of Victoria, British Columbia.

Why is water piling up at Fukushima?

When the reactors were damaged, their automatic shutdowns and safeguard systems failed, and so did the cooling systems. Fission sped up until the fuel’s temperature was hot enough to liquefy, and the rods began to literally melt down. Workers frantically pumped seawater directly over the broken reactors and exposed fuel, leaving highly radioactive water pooling in the buildings and seeping into the groundwater around the plant. “That process has continued since 2011,” says Cullen of the pumping. “The fuel is still warm and it still needs to be kept cool.”

Tanks with radioactive water are piled up at Fukushima No. 1 nuclear power plant in October, which Tepco hopes to release into the sea in an apparent effort to make room to store fuel debris from reactors.

photo：The Japan Times

While some of this water can be reused in cooling the hot reactors, some must be contained and stored after coming in contact with the reactors. “TEPCO … has used most of the plant site as a storage area [and has] built tanks to hold this water, because really they … don’t have any other option,” Cullen says. There are just over one million tonnes of water in the tanks as of 2020. TEPCO estimates the site will run out of room for new tanks by 2022, and the contaminated water keeps piling up.

What do we know about the radiation in the stockpiled water?

“When the fuel burns,” Cullen explains, “it produces radioactive elements in a predictable way and so [TEPCO has] a pretty clear picture of what elements are there.” The company says there are potentially up to 62 different radioactive elements in the wastewater, but names only a few, including carcinogenic cesium-137 and strontium-90. TEPCO said in 2018 that the levels of these isotopes in the tanks still exceeded safe limits, despite having gone through several “cleaning” steps. And to make any risk analysis trickier, TEPCO has been vague about the full list of radioactive elements still in the water.

How can the wastewater be treated or cleaned?

This schematic shows the current arrangement of facilities at the Fukushima Daiichi Nuclear Power Plant, including the damaged reactors, water treatment facilities, and storage tanks. Illustration by Mark Garrison (after a graphic from the Tokyo Electric Power Company)

photo：Hakai Magazine

The collected wastewater is filtered through resin beads, which have an electrical charge that attracts radioactive isotopes, including cesium and strontium. The beads are then stored as standard radioactive waste.

Most of the water also goes through further processing, including an advanced liquid processing system (ALPS) that strips charged particles out of the water. ALPS doesn’t remove everything; it leaves an isotope of hydrogen called tritium in the water. Tritium is not known to be harmful to life, although the effects of large doses are untested.

What are the disposal options for this wastewater, and why is Japan considering the ocean?

Disposal options are very limited. Since dosage determines toxicity, any scheme must dilute the radioactive water as much as possible. An expert panel assembled to find solutions focused on two potential options: vaporizing the water and dispersing it into the atmosphere from a very tall stack, or dumping it in the ocean.

The expert panel advised the Japanese government in 2020 that ocean dumping was preferable. The International Atomic Energy Agency, the United Nations organization responsible for nuclear monitoring, agreed it was feasible. TEPCO says that if it receives approval, the water in the tanks would be released into the sea offshore Fukushima very slowly, over several decades. Cullen notes that there are risks to not dumping the water. “By storing on the site,” he says, “you risk potential uncontrolled release due to another natural disaster or human error.”

Who will oversee and monitor any release?

The United Nations International Maritime Organization administers the London Protocol, a 2006 agreement governing waste in the ocean, to which Japan is a signatory. The protocol prohibits all dumping of nuclear waste so Cullen says it’s unclear what legal options would permit the dumping, but monitoring before, during, and after any planned release would be critical.

photo：thedailybeast.com

If the water is dumped in the ocean,

could it impact human or marine life?

There’s no way to test the impacts of ocean dumping ahead of time. The only way to anticipate the impacts is to look at studies of previous releases of radioactive material into the ocean, as well as studies of the effects radioactive isotopes have on the body.

The isotopes cesium-137 and strontium-90 can be harmful because they enter cells through the same pathways as the nutrients potassium and calcium. An organism could easily incorporate radioactive cesium or strontium into its body, as if it were a nutrient. These isotopes alone aren’t toxic, but their decay is. “When they decay, they generate free radicals,” Cullen says, referring to certain harmful forms of oxygen. “And those can attack important molecules, like DNA inside your cells, and cause problems in replication, and cause illnesses like cancer.”

Cesium can also biomagnify—increase in concentration as it moves through the food chain—to build up in top predators. A study has linked carbon isotopes in seals off the coast of Scotland, for instance, to material released from a nuclear waste disposal site at Sellafield, England. Measurements off the coast of Japan in 2011 identified radioactive cesium from the Fukushima incident throughout the food web, with higher levels in organisms closer to shore. Since the second quarter of 2015, cesium levels in all organisms have been well below Japan’s safety limits for human consumption, but the isotope has persisted.

The effects of dumping the water remain unknown. “Determining what the risk would be to the public and to the environment,” Cullen says, “could only be done if we knew exactly what was in the tanks. And at this point, we don’t.”

photo:REUTERS

How have the public and other countries reacted?

Neighboring countries have expressed concern. South Korea, for one, has banned the import of seafood from Fukushima.

One key group opposing ocean dumping is Fukushima’s local fishers. “Their industry and their livelihoods have been basically destroyed by the disaster,” says Cullen. Following the nuclear meltdown, all exports of seafood from the area were halted. Since then, the fishers have slowly rebuilt their industry, with levels of any radioactive elements well below safe consumption levels. Dumping wastewater nearby could destroy this nascent progress.

Japan has been holding talks and evaluating options throughout 2020 and must soon announce its final decision on the wastewater’s fate. Every option carries risks. What is clear is that fishers, neighboring countries, and other stakeholders can only weigh these risks once they know how many radioactive particles, and of what types, are in the water.

photo:The Idependent

Japan court nixes approval of

post-Fukushima nuclear safety steps

A Japanese court on Friday, for the first time, revoked the government's approval of operating a nuclear plant under new safety regulations developed in the wake of the 2011 Fukushima nuclear disaster.

The Osaka District Court ruled in favor of about 130 plaintiffs who claimed that the Nos. 3 and 4 reactors of Kansai Electric Power Co.'s Oi nuclear plant in Fukui Prefecture are vulnerable to a major earthquake.

In the ruling, Presiding Judge Hajime Morikagi said the Nuclear Regulation Authority's safety screening "has errors and flaws that should not be overlooked" as its estimates needed to factor in a potentially much larger earthquake around the plant.

File photo taken Oct. 20, 2020, shows No. 3 (R) and No. 4 reactors at Kansai Electric Power Co.'s Oi nuclear power plant in Fukui Prefecture, central Japan.

photo:kyodo news

The plaintiffs claimed the utility, known as KEPCO, had underestimated quake hazards using an insufficient formula in calculating the so-called standard ground motion, or the maximum shaking that the reactors could withstand during a quake.

The nuclear watchdog countered that the 2017 regulatory approval based on KEPCO's estimate for the maxim possible ground motion, calculated by such elements as past quake data and geographical structures, of 856 gal was appropriate, adding their claim lacked scientific rationality.

It is the first time a Japanese court has withdrawn government approval granted to a power company to operate a nuclear plant under the safety standards set in 2013 following the meltdowns at the Fukushima Daiichi power plant triggered by a major earthquake and ensuing tsunami.

While the two reactors in Oi in the central Japan prefecture have been idle due to regular inspections since earlier this year, the ruling will not take effect if the NRA appeals the decision.

But the ruling may have an impact on the operations of not only the nuclear plant on the Sea of Japan coast but also other reactors in the country that went back online under the new rules.

The Osaka-based power company, which was part of the lawsuit as a supporting intervenor, suggested it will appeal the ruling with the NRA, saying the decision was "extremely regrettable and totally unacceptable."

A team of lawyers for the plaintiffs, including residents in the prefecture and other parts of the country, released a statement welcoming the ruling and the court's "sincere and serious deliberations," also demanding the immediate abolition of all "dangerous" nuclear reactors in the country.

"(The ruling proves that) KEPCO underestimated the scale of an earthquake and that the NRA's judgment was also too lenient," said Takumi Saruhashi, 66, a member of the Oi town's assembly, who has questioned the safety of the plant for a long time.

photo:CNN

However, an Oi resident in his 60s expressed worries about the decision, "If the reactors are stopped for a prolonged period, the local economy, which is already battered by the coronavirus pandemic, will worsen further."

"We believe we were unable to earn the court's understanding regarding our claims," the NRA said in a statement. "We will have discussions with the ministries and agencies concerned and respond accordingly."

The Nos. 3 and 4 reactors started commercial operations in 1991 and 1993, respectively, and became the first to resume operation in 2012 under the then government's tentative safety rules, while others remained offline in the aftermath of the nuclear disaster.

The utility, meanwhile, has decided to decommission the aging Nos. 1 and 2 reactors at the Oi plant.

来源：The Japan Times，Hakai Magazine，Kyodo News，图片来源于网络，如侵删。

编辑：俞梦婕

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