Twelve years after 3/11, dispute grows over Fukushima’s radioactive soil
BY TOMOKO OTAKE, STAFF WRITER, https://www.japantimes.co.jp/news/2023/03/10/national/dispute-fukushima-radioactive-soil/
OKUMA, FUKUSHIMA PREF. – On the surface, everything seems to be under control at the expansive site storing radioactive soil collected from across Fukushima Prefecture in the aftermath of the 2011 core meltdowns at the Fukushima No. 1 nuclear power plant.
Since 2015, the Interim Storage Facility, which straddles the towns of Okuma and Futaba and overlooks the crippled plant, has safely processed massive amounts of radioactive soil — enough to fill 11 Tokyo Domes — in an area nearly five times the size of New York’s Central Park. The soil was collected during decontamination procedures in Fukushima’s cities, towns and villages that were polluted by the disaster.
Here, black plastic bags full of contaminated soil are put on conveyor belts and unpacked. The contents are sifted through to remove plastic, leaves, twigs and other nonsoil waste. Then the soil is taken to dump zones, where it’s buried in 15-meter-deep pits with protective sheeting and a drainage pipe at the bottom so that radioactive cesium won’t leak into the ground. Finally, the soil is covered with noncontaminated soil and topped with a lawn. Areas where the work has been completed look like soccer fields.
The level of radiation here is about 0.2 microsieverts per hour (uSv/h), explained Hiroshi Hattori, an official at the Environment Ministry’s local office, during a recent tour of the areas where the polluted soil is buried. The radiation level there is harmless to humans, though higher than an average of 0.04 uSv/h elsewhere in Japan.
“It’s higher not because of the soil, but because of surrounding forests (which have not been decontaminated).”
The problem is that, as smooth and orderly as its operations are, the site is only a temporary home for the radioactive soil. Nobody knows where this massive pile of dirt will eventually end up. All that is certain is that the central government has pledged to — and is legally obliged to — move all of the soil out of Fukushima Prefecture by 2045.
This unresolved soil issue — along with the lingering dispute over the planned ocean release of tritium-laced wastewater from Fukushima No. 1 — is a sour reminder of the enormous toll the nuclear disaster in Fukushima has inflicted on the country and beyond.
Opposition from residents
The soil is a product of years of state-funded measures to bring radiation levels down in communities affected by the disaster. The government drew up a “decontamination road map” soon after the accident, in the hopes of a speedy return of residents to their hometowns.
The desire to avoid moving the massive amount of soil again — and to make it easier to find a final destination for it — has also led the Environment Ministry to try to reduce its volume first by reusing some of the less contaminated mud for public works projects across the nation. That way, only a quarter of the total amount that contains over 8,000 becquerel per kilogram of cesium will be subject to final disposal, the ministry says.
But it’s a tough sell. In December, the ministry held its first round of meetings with residents in areas of greater Tokyo where pilot projects to utilize the soil under the 8,000 Bq/kg threshold are planned: the Shinjuku Gyoen National Garden in Tokyo, the National Environmental Research and Training Institute in Tokorozawa, Saitama Prefecture, and the National Institute for Environmental studies in Tsukuba, Ibaraki Prefecture.
Nearby residents vehemently opposed the plan. Last month, they formally demanded that the ministry cancel the pilot projects, under which the ministry plans to bury radioactive soil underneath a 50 cm layer of cover soil, for flower beds and parking lots.
Roads, tidal walls and dams
Though little known until recently, the ministry released a policy document in 2016 that outlined the “safe use” of radioactive soil with radiation levels of 8,000 Bq/kg or less. According to the document, the government will divert such soil to embankments in public works projects “whose management entities and responsibilities are clearly defined.”
Roads, tidal walls, seaside protection forest and earthfill dams are some of the projects where use of the soil is envisioned, the document says.
The plan has raised the eyebrows of not just residents but also experts.
“Japan is very seismic and we have (harsh) weather and typhoons,” said Azby Brown, architect and lead researcher for Safecast, a citizen science group that has independently measured and publicized radiation levels in Fukushima and elsewhere.
“The half-life of cesium-137 is 30 years. It’s going to stay radioactive for a long time. What happens when these embankments get old?… It is not a very rational or sound decision, from the sense of certainly the perception of safety.”
Kenichi Oshima, professor of energy policy at Ryukoku University in Kyoto, questions the rationale of treating the soil of 8,000 Bq/kg or less as safe, pointing to a “double standard” between the ministry’s policy and the rigorous control of waste required for other nuclear power plants under the Nuclear Reactor Regulation Law. That law states only waste with radiation levels under 100 Bq/kg is considered safe enough to be reused.
All of the radioactive waste produced by the Fukushima disaster is covered by a separate “special law” that went into force in 2012. This says that Tokyo Electric Power Co. Holdings (Tepco), the operator of Fukushima No. 1, is responsible for the handling of the radioactive waste and soil within its property, while the Environment Ministry is responsible for the disposal of the 3/11-borne radioactive waste outside the plant, though the law itself does not mention the reuse of soil that has been decontaminated.
The ministry has explained that the 8,000 Bq/kg threshold keeps it consistent with the level of “designated waste materials” stipulated in that special legislation. When people are exposed to waste below 8,000 Bq/kg, the additional radiation exposure is limited to less than 1 millisievert per year, not a level that causes health concerns, according to the ministry.
“Granted, soil with 8,000 Bq/kg of radioactive materials is not one that immediately kills people who touch it,” Oshima said. “But it is low-level radioactive waste nonetheless, and so should be managed properly as such, just like low-level radioactive waste from other nuclear power plants is. It’s just inconceivable that it would be utilized as materials for infrastructure that people will be using often.”
Public support elusive
On Feb. 24, Environment Minister Akihiro Nishimura reiterated the ministry’s stance, telling a news conference that utilization of soil outside the prefecture is “important to realize its final disposal outside the prefecture (of Fukushima).”
“We would like to continue explaining our stance in detail so as to nurture public understanding,” he said.
But to nurture this understanding about an issue as serious as radioactive waste, everyone who has a stake should be involved in the decision-making process, Brown says.
“The strong consensus internationally regarding where to put things like radioactive waste requires full agreement and participation by all of the stakeholders, all of the citizens, everyone who’s involved,” Brown said. “What we usually see often in Japan in general, and certainly regarding the Fukushima issues, is that a decision is made at the top. It’s decided, it’s announced and then they try to persuade people to go along with it. This is the case with the water release issue (as well as) the soil issue.”
Around this spring or summer, the government and Tepco hope to begin discharging water that has all the radioactive nuclides except tritium removed. Construction work is already under way at the seaside plant to install an undersea tunnel, through which the water will be released 1 kilometer offshore.
The so-called JESCO law, which went into effect in 2014, gives legal grounds for the creation of the government-funded entity that runs the interim storage site, as well as the obligation for the central government to move the soil out of Fukushima by 2045. The obligation was written into law following a political compromise with the Fukushima Prefectural Government, with officials from the national government saying they “considered the excessive burden” being shouldered by the people of Fukushima.
Both Oshima and Brown, however, say they find the government’s plan to recycle the dirt out of line.
In fact, Oshima says the best solution would be to set aside an area and make it a controlled zone for all the polluted soil for 50 years until the radioactive cesium decays, which is how waste from other nuclear plants is handled, and is what the final disposal site is going to look like.
He cites a 2017 report by the Japan Atomic Energy Agency that estimated the size of the area needed for final disposal, which should be ready by 2045. If the volume of the soil is estimated at 20 million cubic meters, a subsurface ground facility for its final disposal will need to measure about 1.3 km by 1.3 km, the report concluded.
“It may sound like a huge space, but both the national government and Tepco have vacant land plots of that size,” Oshima said. Once the soil’s use as construction materials is greenlighted, however, it would be transported nationwide, and it would be impossible to track and measure its radiation doses, he argued.
“If the soil is properly stored in a controlled area, it would make the public feel so much more at ease.”
Posted by Christina Macpherson |
Fukushima continuing, Reference, wastes
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