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Fukushima Reaches a Turning Point

by Citizens’ Nuclear Information Center · September 30, 2022

By Yamaguchi Yukio (CNIC Co-Director)

After the nuclear catastrophe in Fukushima in March 2011, the town of Futaba, located in Hamadori (the Fukushima coastline), became the only municipality in Fukushima Prefecture to decide to move its administration out of the prefecture. After changing evacuation sites several times, gradually moving further and further away from Futaba, the town’s government offices and many of its residents settled in a disused school in Kazo City, Saitama Prefecture, at the end of March 2011. It seemed as if the nuclear power plant town, where Fukushima Daiichi Nuclear Power Station (FDNPS) reactors Units 5 and 6 are located, had “drifted” 250 kilometers away from home. The evacuation was ordered based on the Special Act on Nuclear Emergency Preparedness and Response, and it was a difficult evacuation, the people evacuating “with nothing but the clothes on their back.”

The evacuation order for Futaba Town was lifted on August 30 this year, eleven-and-a-half years after it was imposed. However, there are very few who are willing to return to their hometown. As of March 2022, 19 households (26 people), or 0.4% of the pre-disaster level, had applied for “Preparation of Accommodation.”* The rich natural environment that was once part of the area no longer exists, and there is no prospect for the revival of community life.

The decommissioning of the plant at FDNPS is not expected to be completed anytime soon, as nothing like this has been experienced before and the radiation is likely to cause unexpected issues. That is not a problem when fission is used as a nuclear weapon, because the objective is to annihilate the opponent. However, that is not the case for “commercial use.” International organizations promoting nuclear power have set “standards” (radiation dose limits), but they are not reliable. It is impossible to properly evaluate the effects of low-dose exposure with current scientific knowledge alone. It is also a trans-scientific issue (a question that can be asked by science but cannot be answered by science).

The government decided on a plan to treat the radioactive water from FDNPS with ALPS, reduce its radioactivity level, and then discharge it into the ocean. The plan is to be implemented from 2023. The government and those who support the plan claim that there is no safety problem because the concentration will be much lower than the standard, even though the “standard” itself is questionable. However, that cannot be proven. It is only possible to prove it by repeating experiments under exactly the same conditions (including in the natural environment) as exist in reality and obtain results with a sufficiently high degree of confidence in the effects on humans as well as on ecosystems. It may be possible to do so, but it would probably take hundreds of years. The experiments might also lead to irreversible disasters. This kind of “experiment” is not feasible because it would take a long time and be too costly. In addition, simulations are also unlikely to allow us to draw solid conclusions.

There are many who are opposed to the oceanic release plan by the government and TEPCO, and who have presented reasons for their opposition. One thing I would like to add about “harmful rumors” is that this expression has the connotation of “irresponsible rumors that make something which is actually harmless appear to be harmful.” I do not agree with this connotation.

The government and nuclear energy proponents pushed forward the nuclear power plants without regard for the opinions of citizens and residents. This caused a nuclear catastrophe, the government has adopted an evacuee return policy without taking responsibility, and it is now about to discharge contaminated water into the ocean. The reason why such an absurdity has occurred is that the government has become extremely powerful. The separation of legislative, administrative, and judicial powers is said to be the basis of democracy, but the equilibrium of these three powers has been seriously disturbed. Nevertheless, the Mito District Court decision (Tokai Daini NPP Lawsuit, 18 March 2021) , the Sapporo District Court decision (Tomari NPP Lawsuit, 31 May 2022), the Supreme Court’s opinion by Justice Miura (17 June 2022), and the Tokyo District Court judgement (TEPCO Shareholder Lawsuit, 13 July 2022) remind us that the judiciary still exists.

Sun Yat-sen (1866-1925) once advocated the idea of a “five-power constitution” on the grounds that the three powers alone were not sufficient. Considering the current situation in Japan, I suggest the right to vote alone is powerless to curb the tyranny of the government. We need more powerful civic rights so that ordinary citizens can get together and be as powerful as the other three institutions.

Although the existence of “experts” is crucial in today’s world of science and technology, there are still many problems that cannot be answered by “experts” alone. Eleven-and-a-half years after March 11, METI committees, acting as if Fukushima is now history, often use expressions such as “innovative reactors” and insist that “nuclear power is the key to decarbonization.” I believe citizen power is needed more than ever before.

*”Preparation of Accommodation”: A system that allows disaster victims to stay overnight in their homes, which is prohibited in the evacuation zone, in order to facilitate preparations for a smooth resumption of life in their hometowns after the evacuation order is lifted.

Source: https://cnic.jp/english/?p=6286

October 1, 2022 Posted by | Fuk 2022 | , | Leave a comment

Ministry of the Environment – Draft Demonstration Plan for Reclamation of Removed Soil, Seeking Use as Road Fill

August 4, 2022

The Ministry of the Environment has compiled a draft plan for a demonstration project to recycle removed soil in order to reduce the final disposal volume of waste generated by the decontamination project for the Fukushima Daiichi Nuclear Power Plant accident. The project aims to expand the use of recycled materials based on removed soil at intermediate storage facilities in Fukushima Prefecture (in the towns of Okuma and Futaba), and is exploring the use of the materials for road fill. The design and construction methods and procedures will be studied until October, and construction will be carried out between October and January 2023. The project will be implemented from October to January 2023. After January, various tests and monitoring will be conducted. The project will also conduct demonstrations outside of the prefecture to demonstrate the use of recycled materials for parking lot construction and other purposes.
 On March 3, the first meeting of the “Working Group to Study the Recycling of Soil Removal at Interim Storage Facilities” (WG, chaired by Professor Takeshi Katsumi, Graduate School of Global Environmental Studies, Kyoto University) was held in Tokyo, where the draft plan was presented. The WG will organize and evaluate the findings from the demonstration project, and study measures to safely use the removed soil as recycled materials. A practical guide for recycling will also be prepared.
 According to the draft plan, recycled materials will be used for roadway fill in the interim storage facility. The road to be used for the general road standards is assumed to be a structure with sidewalks and a daily traffic volume of 4,000 to 20,000 vehicles (Class 3 and Class 2). The road is assumed to be a structure with sidewalks. Evaluation will be conducted after actual construction. The results of the project will be reflected in the guide.
 A demonstration project will be conducted outside of Fukushima Prefecture with the aim of realizing final disposal outside of Fukushima Prefecture. Recycled materials will be used for the roadbed of parking lots, and different reclamation patterns will be demonstrated, including differences in pavement and roadbed materials. Cases in which recycled materials are used to create flowerbeds and plazas will also be investigated. During the construction and use of the reclaimed materials, air dose rates in and around the reclaimed areas and radioactive concentrations in seepage water will be measured to confirm safety. Construction will be conducted this year, and monitoring will begin after completion.

August 5, 2022 Posted by | Fuk 2022 | , , , | Leave a comment

Japan Still Facing Challenges in Reconstructing Fukushim

Reconstruction without full decontamination is nothing else but a pipe dream, mostly made out of PR and propaganda…

July 19, 2022

Tokyo, July 19 (Jiji Press)–Reconstruction of areas in Fukushima Prefecture hit by the March 2011 nuclear accident has shown progress, but a number of challenges have yet to be overcome, including construction of essential facilities for everyday life and creation of jobs to bring back residents who evacuated to other prefectures.
The decommissioning of the meltdown-hit Fukushima No. 1 nuclear power plant of Tokyo Electric Power Company Holdings Inc. should also be pushed forward.
With evacuation orders in afflicted areas having been lifted in stages, the number of evacuees outside the northeastern prefecture has now fallen to some 30,000 from the peak level of over 160,000.
Most recently, it has been decided to remove Aug. 30 the evacuation order for the so-called specified reconstruction zone in the town of Futaba, which co-hosts the Fukushima No. 1 plant, crippled by the March 11, 2011 earthquake and tsunami, and is the only remaining completely evacuated municipality.
After the central and Futaba town governments reached the agreement to lift the order for the area around Futaba Station on the JR Joban Line, Chief Cabinet Secretary Hirokazu Matsuno visited nuclear accident-hit areas for two days through Saturday.

July 22, 2022 Posted by | Fuk 2022 | , , | Leave a comment

Fukushima Prefecture Bar Association makes an emergency statement on the Supreme Court ruling on the nuclear power plant lawsuit

July 19, 2022
In response to the Supreme Court’s ruling last month that the government is not responsible for the nuclear power plant accident, the Fukushima Prefecture Bar Association called for a decision based on the actual situation in the other lawsuits.

On March 17, the Supreme Court ruled against the government’s responsibility in four class action lawsuits over the nuclear accident, stating that even if the government had obliged TEPCO to take measures to prevent a nuclear accident, there is a high possibility that an accident would have occurred.

In response, the Fukushima Prefecture Bar Association held a press conference in Fukushima City on March 19 and issued an emergency statement.

Daisuke Yorikane, attorney-at-law of the Fukushima Prefecture Bar Association, said, “In terms of responding to the wishes of the litigants, we are disappointed because we wanted the Supreme Court to give a proper opinion on the state of nuclear safety regulations in the country.

The statement pointed out that the Supreme Court’s decision was based solely on the theory of causality and could not be said to be responsive to the wishes of the plaintiffs.

The statement called for the Supreme Court to make a decision that recognizes the responsibility of the government based on the actual conditions of the other cases that are still ongoing.

Attorney Yorikane said, “I hope that (the government) will actively fulfill its responsibilities regarding the exercise of its authority based on scientific findings.

The Fukushima Prefecture Bar Association also referred to the government’s interim guidelines, which serve as the standard for compensation for damages, and called for a review of the guidelines according to the actual conditions of the damage in the future.
https://newsdig.tbs.co.jp/articles/tuf/99511?display=1&fbclid=IwAR1My4O3GcaHfiS3tUv-gwAaC2TiRnu0VK5ZeY4UQ8t-Sv7CL5Ig4bwuLBc

July 22, 2022 Posted by | Fuk 2022 | , , , , , | Leave a comment

Persistent impact of Fukushima decontamination on soil erosion and suspended sediment.

Published: 14 July 2022

Abstract

In Fukushima, government-led decontamination reduced radiation risk and recovered 137Cs-contaminated soil, yet its long-term downstream impacts remain unclear. Here we provide the comprehensive decontamination impact assessment from 2013 to 2018 using governmental decontamination data, high-resolution satellite images and concurrent river monitoring results. We find that regional erosion potential intensified during decontamination (2013–2016) but decreased in the subsequent revegetation stage. Compared with 2013, suspended sediment at the 1-year-flood discharge increased by 237.1% in 2016. A mixing model suggests that the gradually increasing sediment from decontaminated regions caused a rapid particulate 137Cs decline, whereas no significant changes in downstream discharge-normalized 137Cs flux were observed after decontamination. Our findings demonstrate that upstream decontamination caused persistently excessive suspended sediment loads downstream, though with reduced 137Cs concentration, and that rapid vegetation recovery can shorten the duration of such unsustainable impacts. Future upstream remediation should thus consider pre-assessing local natural restoration and preparing appropriate revegetation measures in remediated regions for downstream sustainability.

Main

Radioactive material leakage from nuclear industry activities or nuclear accidents poses a major threat to the environment and the economy1,2. Historically, widespread radioactive contamination has been observed several times, such as the Kyshtym accident (Soviet Union) in the 1940s–50s3, Windscale accident (England) in 1957 (ref. 4) and Chernobyl accident (Soviet Union) in 1986 (ref. 5). Long-term radiation exposure and radiophobia have increased the health risk and psychological pressure on the people of these regions, resulting in the abandonment of large areas rich in environmental resources and consequently in constrained sustainable human development6,7. As a key means for recovering contaminated regions, mechanical decontamination has been implemented in many legacy sites, including Hanford (United States)8 and Chernobyl9. However, almost all attention has been directed to understanding in situ decontamination effects10,11 and atmospheric particle resuspension issues12 and little is known about if these perturbations would have secondary environmental impacts on their downstream catchments for the long-term.

On 11 March 2011, the most recent large-scale nuclear accident happened at the Fukushima Daiichi Nuclear Power Plant (FDNPP), Japan13. Over 2.7 PBq of fallout 137Cs (half-life T1/2 = 30.1 yr) from the FDNPP was deposited in the terrestrial environment, causing long-term radioactive contamination on large-scale neighbouring catchments13,14. To recover contaminated soil and decrease the exposure dose in Fukushima, the Japanese government evacuated the residents in 2011 and large-scale decontamination was implemented in contaminated villages15,16 in 2012. Within a few years, dramatic land-cover changes occurred in the agricultural regions where 5 cm of the surface soil and vegetation were removed and replaced with uncontaminated soil (Fig. 1), with the subsequent natural restoration promoting revegetation in these decontaminated regions11,13,16.

The effectiveness of such intensive decontamination at reducing radiation exposure in situ is apparent, with air dose rates decreasing by 20–70% after decontamination13. However, as 137Cs can firmly bind to clay minerals, it is transported along with suspended sediments (particulate 137Cs) in the river system to the Pacific Ocean17,18. Comprehensively assessing the impacts of land-use changes in decontaminated regions on the downstream ecosystem is also necessary from the perspective of environmental sustainability. Moreover, recent studies have shown notable differences in the reduction in the particulate 137Cs concentration over time across 30 rivers in Fukushima19,20, further underscoring the need to study land-use impacts on downstream particulate 137Cs discharge into the ocean.

In addition to contaminant migration, land-use changes induced by strong perturbations (for example, decontamination) also alter land–ocean sediment transfer patterns21,22, which in turn affect elemental cycles23, biodiversity24 and global climate25. Systematically assessing the perturbations’ impacts on downstream river suspended sediments (SS) has thus become a joint goal of many related disciplines and a key part of developing science-based catchment management strategies26,27,28,29. However, owing to the limited availability of reliable and concurrent river monitoring data, how downstream river SS variations and land-use changes are linked remains unclear21.

With approximately 11.9% of the watershed area subjected to government-led decontamination between 2013 and early 2017, the Niida River Basin in Fukushima (Fig. 2a)11,30 provides an excellent opportunity to examine the long-term impact on the dynamics of SS and particulate 137Cs in river systems. Previous short-term river studies19,20,31,32,33,34 have suggested an increased river SS load and decreased particulate 137Cs concentrations during decontamination. Several studies that analysed geochemical fingerprints in deposited sediments have implied a significant contribution of sediment sources from the decontaminated regions to the river35,36,37. Yet, given that threats to sustainable catchment management from anthropogenic perturbations are often long-term28,29, more comprehensive and reliable data on quantified land cover and continuous river records are required to explore the effect of decontamination on river SS and particulate 137Cs discharge.

Here we provide a comprehensive assessment of the impacts of land-use changes in decontaminated regions on river SS and particulate 137Cs dynamics, as well as the downstream discharge. We mapped the evolution of decontaminated region boundaries using governmental decontamination documents (Fig. 2b), photographed the land cover in the decontaminated regions using drones and quantified the land-use changes using the normalized difference vegetation index (NDVI) at 10 m spatial resolution. Meanwhile, we conducted a long-term field investigation (Methods and Supplementary Table 1) spanning the decontamination (2013–2016) and natural restoration (2017–2018) stages to continuously record the fluctuations in water discharge and turbidity (10 min temporal resolution) and particulate 137Cs concentrations, both upstream and downstream. Combining the above quantitative data, we systematically reveal that long-term land-use changes in upstream decontaminated regions greatly affect sediment and 137Cs discharge from downstream river systems into the Pacific Ocean.

Land-cover changes in decontaminated regions

Regional decontamination was accomplished in March 2017, spanning over 22.9% and 11.9% of the upstream (Notegami) and downstream (Haramachi) watershed areas, respectively (Fig. 2c). In 2014, agricultural land (18.02 km2) was one of the major land uses in the regions where decontamination was ordered, with a significant increase of over 720% compared with that in 2012. Conversely, the changes in the ordered grassland (1.93 km2) were minimal, with an approximately 26% increase between 2012 and 2014. Given that overall land-cover changes were more pronounced in agricultural lands than in grasslands or residential lands, large-scale agricultural land decontamination may severely alter landscape erodibility and consequently the sediment supply. Moreover, the proximity of the decontaminated agricultural land to rivers increases sediment transport from terrestrial environments.

Drone photographs (Fig. 3a and Supplementary Fig. 1) showed significant land-cover changes in the upstream decontaminated regions. For instance, the agricultural land at the Hiso site (D3, Fig. 3a) was almost bare in August 2016 when the decontamination was completed. However, natural restoration caused the recovery of vegetation during the post-decontamination stage (August 2018). Considering the decontamination sequence and seasonal dependence of the plant growth cycle38, drastic spatiotemporal land-cover changes in the decontamination regions are conceivable.

To quantitatively estimate and compare land-cover changes in the decontaminated regions, we generated NDVI maps in these regions based on the available satellite images from Sentinel 2 and the Moderate Resolution Imaging Spectroradiometer (MODIS) between 2011 and 2018. The comparison between realistic scenarios and Sentinel 2-based NDVI maps (spatial resolution: 10 m) from drone observation sites (Fig. 3a and Supplementary Fig. 1) confirmed the feasibility of NDVI images in distinguishing bare land and agricultural land with vegetation cover. To improve the temporal–spatial resolution of the NDVI dataset, we used the enhanced spatial and temporal adaptive reflectance fusion model (ESTARFM)39 to fuse Sentinel 2 and MODIS maps. Subsequently, we used interpolation to link these newly generated NDVI data (spatial resolution: 10 m) and plotted daily NDVI variations for all decontaminated regions between 2011 and 2018 (Fig. 3b).

In the daily NDVI variation curve, the peak NDVI during 2013–2014 was similar to the pre-decontamination stage (2012) but decreased by approximately 10% in 2016. After decontamination, the peak value presented an increasing trend under the influence of vegetation recovery. However, as the government lifted the evacuation zone after 2017 and allowed the residents to return, vegetation was again removed from some areas planned for agricultural activities in 2018 (Supplementary Fig. 1b). Further analyses of the NDVI variations in the decontaminated regions scheduled in 2012 (Fig. 3c), 2013 (Fig. 3d) and 2014 (Fig. 3e) showed that the NDVI peaks were decreased by approximately 12%, 11% and 15%, respectively, within 2–3 years after decontamination was ordered, thereby providing unambiguous evidence for decreasing vegetation land cover caused by decontamination.

We converted all NDVI maps derived from ESTARFM-images to C × P (cover management and support practice factors, respectively) maps using empirical models40,41. We then estimated erosion potential (that is, K × LS × C × P in the revised Universal Soil Loss Equation (RUSLE); Methods) maps using the LS (slope length and slope steepness factors, respectively) map (Supplementary Fig. 2) and K (soil erodibility) factor in the decontaminated regions. We found that the slopes of decontaminated regions were generally similar for each decontamination-ordered year (Supplementary Fig. 2), suggesting that the erosion potential was consistent with the NDVI in the decontaminated regions. Therefore, we also estimated the daily variation curve of the erosion potential using the mean CP, LS and K factors in the decontaminated regions.

Here we show the ESTARFM-based NDVI (Fig. 3f) and erosion potential (Fig. 3g) during the summer season for each year (specific periods in Supplementary Table 2). NDVI showed a decreasing trend from 2013 to 2016, while the erosion potential peaked in 2016, representing approximately 98% and 52% increases over the pre-decontamination (2011) and natural restoration (2018) stages, respectively. Combining the corresponding NDVI (Supplementary Fig. 3) and erosion potential maps (Supplementary Fig. 4), significant changes in the spatial differences between the land cover and erosion potential during decontamination were also observed.

Response of river SS to land-cover changes

The downstream river SS load (L; Fig. 4a) exhibited a strong correlation with water discharge (Q) during the monitoring periods (Supplementary Fig. 5 and Supplementary Table 3). Under the range of water discharges from 0.1 to 100 m3 s−1, river SS carrying capacity exhibited a considerable increase from 2013 to 2016 and a slight decrease after decontamination (2017 to 2018). Contrastingly, the range of water discharges was relatively narrow upstream, and a steady decrease in SS loads has been observed since 2015. Although the above result suggests an increase in SS supply during the decontamination stage, the high SS carrying capacity in 2015 is not consistent with the actual decontamination progress. Since decontaminated regions tend to be bare land, sediment loads are prone to increasing during rainstorms due to soil erosion. Governmental decontamination plans showed that over 50% of agricultural land decontamination was planned to be implemented in 2016, implying that the erosion potential of the decontaminated regions should have been higher in 2016, rather than in 2015.

The variations in downstream river SS loads over the 6 years (Supplementary Table 4) exhibited a similar trend to peak river SS load in 2015 (126.7 ± 0.3 Gg yr−1). This was an approximately 1,776%, 140% and 215% increase relative to that of 2013, 2016 and 2018, respectively. The historical rainfall records (Fig. 4b) show that the rainfall in September 2015 (551 mm) was more than two-fold greater than that during the same period in 2016 (274 mm), implying that the SS peak may be related to strong runoff. Here we estimate the SS loads at 1-year-flood discharge (Q = 95 m3 s−1) using established LQ curves, which allow for the comparison of dynamic variations in SS loads under the same flood conditions. In Fig. 4b, a significant increasing trend during the decontamination period is shown, with a 237.1% increase in 2016 compared with 2013. After decontamination, the SS loads drastically decreased by approximately 41% from 2016 to 2017, implying changes in sediment yield and transfer patterns due to natural restoration. These results reveal that river SS loads responded closely to land-cover changes during the study period.

To better explore the response of river SS load to land-cover changes, we extracted river monitoring data during each rainfall event and quantitatively linked the river SS to the corresponding soil loss from the decontaminated regions. We found that SS loads during rainstorms were highly correlated with water discharges in both upstream and downstream areas (Supplementary Fig. 6). Comparing similar rainfall events, significantly greater SS concentrations are observed in 2015–2016 than in other years (Supplementary Figs. 7 and 8). Considering that the land-cover changes induced by decontamination were more pronounced in the summer season, the regression was performed for SS loads between May and October and soil loss during the corresponding period. A more significant correlation was observed (Fig. 4c) between estimated soil loss by RUSLE and SS load upstream (R2 = 0.55, P < 0.01, N = 34) than downstream (R2 = 0.27, P < 0.01, N = 52). Eliminating the effect of rainfall and normalizing by discharge (Fig. 4d) results in a more evident relationship between the erosion potential and SS loads downstream (R2 = 0.35, P < 0.01, N = 52). Overall, these results demonstrate the connection between river SS dynamics and land-cover changes in the decontaminated regions. The short distance between the upstream catchment and decontaminated regions makes soil erosion a critical driver for upstream river SS transport, whereas the downstream river is dependent on long-distance SS transport, making water discharge an important driver for the downstream catchment.

Long-term impact on river SS and 137Cs discharge

From August 2014 to March 2017, the particulate 137Cs concentration in Haramachi exhibited a steep decrease, contrasting remarkably with the limited 137Cs variation observed in the early decontamination stages (January 2013 to August 2014; Fig. 5a). The effective half-life of the particulate 137Cs (eliminated by the natural attenuation factor) during this decontamination period (1.87 yr) was considerably faster than that of physical decay of 137Cs (30.1 yr), the early decontamination period (16.9 yr) and the surrounding contaminated catchments (mean of 4.92 yr)20. Such a sharp decrease in the 137Cs concentration was also observed at the other three monitoring sites (Supplementary Fig. 9a). Because the 137Cs concentration in decontaminated soil was considerably lower than that in the contaminated soil37,42, these results suggest the contribution of sediment from decontaminated regions to the river system. Moreover, strong negative correlations were observed between measured 137Cs levels and decontamination progress at all monitoring sites (Fig. 5b and Supplementary Fig. 9b), which further supports our interpretation. The observed 137Cs concentration increased by approximately 150% in 2018 compared with that at the end of 2016, which may be caused by the weakened sediment supply from decontaminated regions owing to natural restoration and resulting in a relatively increased contribution of sediments from contaminated forest regions13.

Given that the variation in 137Cs concentrations reflects a change in sediment source, the deviations between the measured 137Cs and the natural decrease in 137Cs derived from surrounding contaminated catchments provide a way to quantitatively estimate the contribution of sediment from decontaminated regions (Fig. 5c). In the early decontamination period, our results showed slight variations in the 137Cs concentration (Fig. 5a), which could be attributed to the contribution of sediment from upstream regions with different degrees of contamination. During the main decontamination period, the erosion potential in the summer of 2015 was approximately 22% higher than that in 2014 and the heavy rainfall caused the largest flooding event during the study period (26-year flood). This may result in the sediment from decontaminated regions not being the dominant source for downstream. In 2016, decontamination caused an increase by approximately 59% in the erosion potential compared with 2013, with the contribution percentage steadily increasing over this period to a maximum of 75.7% ± 3.2% (value ± 95% uncertainty). After decontamination, the decreased contribution of sediment from decontaminated regions and the increased 137Cs concentrations can both be attributed to the reduction of soil loss from upstream due to natural restoration.

The 137Cs discharge from contaminated catchments around the Fukushima region into the Pacific Ocean is another ecological issue of global concern. Our data show that the export flux of particulate 137Cs from the downstream of the Niida river (that is, Haramachi) peaked in 2015 (1.24 TBq yr−1, equalling 0.65% 137Cs loss), which is an approximately 667%, 233% and 429% increase relative to that in 2013, 2016 and 2018, respectively (Fig. 5d). Although such 137Cs loss is negligible compared with the terrestrial inventory, it is approximately 105 times greater than that in the pre-Fukushima stage43,44. Accordingly, the dynamic variations in 137Cs discharge from terrestrial environments into the Pacific Ocean, and its drivers, require more attention in the future.

Here we used SS loads at one-year-flood discharge to normalize the 137Cs flux and found its peak occurred in 2015 (Fig. 5e). Additionally, the reduction of the normalized 137Cs flux from 2013 to 2016 (~32%) was similar to natural attenuation in the non-contaminated catchment (~34%) over same period, which may be due to the increased SS load during decontamination offsetting the role of declining 137Cs concentrations in reducing 137Cs emission. During the subsequent natural restoration period, the rapid NDVI increase (Fig. 3f) suggested vegetation recovery in decontaminated regions and a decrease in regional erosion potential (Fig. 3g). This resulted in an approximately 24% decrease in sediment yield from the catchment and an approximately 31% decrease in the contribution of sediment from decontaminated regions (Fig. 5c) from 2016 to 2018. Due to the mutual balance of these effects, there were no significant changes in normalized particulate 137Cs flux in 2018 compared with 2016.

Discussion

Our work highlights the great potential of interdisciplinary analyses for understanding river SS variation and quantifying the contribution of sediment from specific regions. Fukushima decontamination practices, like a controllable validation experiment, justified the reliability of using long-term 137Cs monitoring data for tracing sediment source dynamics due to specific perturbation. Combining the long-term dataset of 137Cs (or other fallout radionuclides) in SS with remote sensing images would provide additional evidence to determine if the changes in the downstream SS transport pattern are linked to the upstream perturbation.

With these interdisciplinary analyses, we systematically reveal how changes in land use in the decontaminated regions significantly influences downstream river SS and 137Cs discharge into the ocean. Indeed, the secondary environmental impacts of surface remediation are being increasingly considered in the broader field concerning remediation of regions contaminated with hazardous materials (for example, heavy metals and organic contaminants)45. The concept of environmental sustainability-centred green remediation has also been brought up in many scenarios46,47. The Fukushima decontamination practice provides evidence showing that mechanical remediation can cause persistently excessive SS load downstream, though it also reduced river 137Cs concentrations. Since persistently excessive turbidity in rivers affects not only surrounding residents’ water use but also trophic level structure in aquatic environments48, the unsustainable downstream impacts caused by upstream decontamination should be highly regarded. The vegetation recovery after land development is highly dependent on local conditions49, and the soil used for decontamination and local high rainfall amount in Fukushima promoted rapid vegetation recovery11,13, which shortened the duration of such unsustainable impacts. Therefore, future upstream contaminated lands that await mechanical remediation need to consider the pre-assessment of local natural restoration conditions or the preparation of appropriate revegetation measures in the catchments’ regulatory frameworks, which would minimize the impact of long-term decontamination on downstream sustainability.

Methods

Study region

The Niida River Basin (265 km2) is located about 40 km northwest of the damaged FDNPP. The topography of its upstream is almost mountainous and its soil types are mainly cambisols and andosols, while fluvisols are the dominant soil type in the downstream plain50. The monitoring data from the Japan Meteorological Agency show that the average rainfall in the Niida River Basin is greater than 1,300 mm, with more than 75% of the rainfall occurring between May and October. According to the third airborne monitoring survey by the Japanese government, the 137Cs inventory in the Niida River Basin was over 700 kBq m−2 (ref. 14). Because of particularly high contamination in its upstream watershed (over 1,000 kBq m−2)51, the government-led decontamination was implemented in the upstream basin from 2013 to 2016 (~1% of the area was extended to March 2017).

Land-cover observation

We constructed the vector decontamination maps based on the paper maps from the Ministry of the Environment, Japan. The boundaries of the decontaminated regions with different land-use types were first outlined by creating polygons using Google Earth. Subsequently, the projections of these polygons were imported to ArcMap v.10.3 to quantitatively evaluate their area.

During the decontamination (2016) and post-decontamination stages (2018), drone photography was utilized (Fig. 2a, triangle) to compare land-cover changes. A commercially available drone (Phantom 4, DJI product) was employed at 100 m above the ground in Matsuzuka (D1; 37.689° N, 140.720° E), Iitoi (D2; 37.663° N, 140.723° E) and Hiso (D3; 37.613° N, 140.711° E) to take photographs.

Quantification of land-cover changes in decontaminated regions

We calculated NDVI within the boundary of the decontaminated regions to quantify the land-cover changes. Through the spectral reflectance dataset in the red (R, nm) and near-infrared (NIR, nm) regions, the NDVI was calculated as52:

NDVI=NIR−RNIR+R.

(1)

The available satellite images from 2011 to 2018 from Sentinel 2 were downloaded from the United States Geological Survey53, while the concurrent MODIS images were derived from the National Aeronautics and Space Administration’s Reverb54. The wavelength bands and spatiotemporal resolutions of the satellite images used here are summarized in Supplementary Tables 5 and 6.

To confirm the reliability of the newly generated NDVI variation curve, NDVIs for the same date as the Sentinel 2 images were estimated using the interpolation and compared with the Sentinel 2-based NDVI. The linear regression analysis showed that the fitting R2 was 0.99 (N = 16, P < 0.01). We also calculated the NDVI in the decontaminated region based on available satellite images of Landsat 5/7/8 (ref. 53) and established a daily NDVI variation curve. The linear regression analysis also showed a high R2 between two daily NDVI curves (R2 = 0.97, N = 2868, P < 0.01). Therefore, these NDVIs calculated by different satellite images confirmed the reliability of the NDVI variation curve based on ESTARFM.

Estimation of erosion potential in decontaminated regions

To link the land-cover changes in decontaminated regions with the soil erosion dynamics, we defined an erosion potential (K × LS × C × P) based on the RUSLE.

The soil loss (A, t ha−1 yr−1) of a specific region can be estimated as55:

A=R×K×LS×C×P,

(2)

where R is the precipitation erosivity factor (MJ mm ha−1 h−1 yr−1), K represents the soil erodibility factor (t h MJ−1 mm−1), L and S are slope length factor (dimensionless) and slope steepness factor (dimensionless), respectively, and C and P are the cover management factor (dimensionless) and support practice factor (dimensionless), respectively. Because these parameters are often set as fixed values, it is difficult to assess the soil loss dynamics during anthropogenic disturbances. To address this problem, we used daily NDVI data to estimate C × P and then considered these dynamic factors in RUSLE.

Wakiyama et al.40 reported a correlation between vegetation cover in Fukushima and the sediment discharges from the standard USLE plot (that is, soil loss, A) that have been normalized by R, K, S and L factors40,56. Therefore, this empirical equation reflects the quantitative relationship between vegetation fractions (VF) and C × P.

To quantify daily C × P changes in decontaminated regions, we first converted the interpolated daily NDVI into the VF by a semi-empirical equation41:

VF=1−(NDVI−NDVI∞NDVIs−NDVI∞)0.6175,

(3)

where NDVIs and NDVI represent the NDVI value for land cover corresponding to no plants and 100% green vegetation cover, respectively. Since these values mainly depend on plant species and soil types, we followed previous methods applied to agricultural land and set NDVIs and NDVI as 0.05 and 0.88, respectively41.

Subsequently, the C × P was estimated by the empirical equation derived from uncultivated farmlands and grasslands (R2 = 0.47, N = 145)40:

C×P=0.083×e−5.666×VF.

(4)

Since the soil type used for decontamination is generally the same, the K factor was set as a constant (0.039; ref. 40). For the LS factor, we downloaded a digital elevation model from the Geospatial Information Authority of Japan (spatial resolution: 10 m) to build an LS map using55:

LS=[QM22.13]y×(0.065+0.045×Sg+0.0065×S2g),

(5)

where Qa is the flow accumulation grid, Sg represents the grid slope as a percentage, M is the grid size and y is a parameter depended on slope steepness. We here used the y values recommended by a published study, ref. 55.

The calculated LS-factor map (Supplementary Fig. 2) showed a relatively consistent LS distribution in space. Based on the ESTARFM-generated satellite images, we compared C×P and erosion potential (K × LS × C × P) and found a significant correlation (R2 = 0.99, P < 0.01, N = 174). Since these results suggest that LS factors in decontaminated regions have a negligible effect on the erosion potential, the mean LS factor and interpolated NDVI based on the daily variation curve (Fig. 3b) were used to estimate the daily erosion potential.

Monitoring of river discharge and turbidity

The water-level gauges (in situ Rugged TROLL100 Data Logger) and a turbidimeter (ANALITE turbidity NEP9530, McVan Instruments) were installed in each monitoring site to continuously recording the water level and turbidity with a temporal resolution of 10 min. As ocean tides may influence the accuracy of water-level monitoring, the Sakekawa site (M4 in Fig. 2) was excluded from the river monitoring programme.

The recorded water level (H, m) was converted to the water discharge (Q, m3 h−1) based on the annual HQ curves for each monitoring site. These curves were calibrated using a synchronous monitoring dataset of 10-min-resolution water level and discharge provided by the Fukushima prefecture’s official monitoring network57. Because of occasional damage to the water-level gauge at the Haramachi site, the available monitoring data with a temporal resolution of 10 min recorded by the Fukushima prefecture’s official monitoring network57 were used to fill the gaps. The percentages of filling data from official monitoring network were all less than 34% except for 2015 (56.6%). Although similar situations occurred in Notegami, we were unable to fill in gaps with other data due to the lack of a concurrent monitoring network.

The hourly SS concentration (Css, g m−3) at each monitoring site was calculated from the measured turbidity (T, mV) using a calibrated curve20. As the turbidimeter was susceptible to the moss and debris flowing in the river, the dataset was verified with an automated check by HEC-DSSVue (The U.S. Army Corps of Engineers’ Hydrologic Engineering Center Data Storage System) before transforming the data.

The SS load was estimated as the product of the corresponding datasets of discharge and SS concentration, after which we can obtain the annual SS load (L, ton yr−1) by taking the sum:

L=∑(Q×Css).

(6)

We estimated values for gaps including missing and abnormal data through a linear model established by 10-min-resolution monitoring data at the same site. The reliability of the gap-filling strategies used in this study has been documented by Taniguchi et al.19,20 These procedures vastly enhance the possibility of reconstructing the complete dataset. In this study, only the error in converting from water discharge to SS load was considered in the uncertainty assessment, and all estimates were within 0.5% (95% confidential interval) in this case. To reduce the uncertainty of LQ fitting, the 10-min monitoring dataset (discharge and SS load) was transformed to a 1-hour dataset.

Considering the river SS is often transported by discharge, we used downstream LQ curves to estimate river SS loads at 1-year-flood discharge (Q = 95 m3 s−1), which eliminates the influence caused by different annual water discharges. The 1-year-flood discharge was calculated from the daily maximum discharge data from 1 January 2013 to 30 September 2020 at the Haramachi site.

To compare river SS dynamics during rainfall events, we here defined a rainfall event as the increase in water discharge exceeding 1.4 and 1.6 times the baseflow before precipitation for the upstream and downstream catchments, respectively. As a result, a total of 64 and 72 rainfall events from the Notegami and Haramachi sites were identified.

To study the dynamic relationship between soil loss from decontaminated regions and river SS load, we estimated eroded soil amount during each rainstorm using RUSLE. Specifically, the NDVI during a specific rainfall was determined by interpolation. Subsequently, the corresponding C × P can be estimated using equations (3) and (4). With the mean values of the K and LS factors, the erosion potential can then be calculated. Finally, precipitation erosivity factor (Supplementary Table 7) for each rainfall event can be calculated as58:

R=1nj=1nk=1mj(EI30)k,

(7)

where n is the number of years used, mj is the number of precipitation events in each given year j and E and I30 represent each event’s kinetic energy (MJ) and maximum 30 min precipitation intensity (mm h−1), respectively, for each event k. The event’s erosivity, EI30, can be calculated as58:

EI30=(∑r=10ervr)I30,

(8)

where er denotes the unit rainfall energy (MJ ha−1 mm−1) and vr provides the rainfall volume during a set period (r) (mm). For this calculation, the criterion for the identification of a precipitation event is consistent with previous work, that is, the cumulative rainfall of an event is greater than 12.7 mm (ref. 58). If another rainfall event occurs within 6 h of the end of a rainfall event, they are counted as one event. Therefore, the unit rainfall energy (er) can be derived for each time interval based on rainfall intensity (ir, mm h−1)58:

er=0.29[1−0.72e(−0.05×ir)].

(9)

The calculation’s required parameters were derived from the historical precipitation record from the Japan Meteorological Agency59. For the Notegami catchment, the precipitation monitoring data were derived from Iitate. For the Haramachi catchment, the precipitation was obtained from three adjacent monitoring sites (that is, Haramachi, Iitate and Tsushima) with the specific weights of 0.143, 0.545 and 0.312, respectively. These weights were determined by the Voronoi diagram method in a Geographic Information System60.

River monitoring of particulate 137Cs

At each monitoring site, the suspended sediment sampler proposed by Phillips et al.61 was installed at 20–30 cm above the riverbed for the time‐integrated sampling of river suspended sediment. The reliability of this sampler has been widely proven in past studies19,20. After sampling, the trapped turbid water and SS samples were transferred into a clean polyethylene container and stored until laboratory analysis.

The SS samples were separated from the collected water mixture via natural precipitation and physical filtration, dried at 105 °C for 24 h and subsequently packed into a plastic container. The activities of 137Cs in the SS samples (C, Bq kg−1) were determined via the measurement system, which consists of a high-purity germanium γ-ray spectrometer (GCW2022S, Canberra−Eurisys, Meriden) coupled to an amplifier (PSC822, Canberra, Meriden) and multichannel analyser (DSA1000, Canberra, Meriden). The measurement system was calibrated with the standard soil sample from the International Atomic Energy Agency. Under the 662 keV energy channel, each measurement batch would take approximately 1–24 h to make the analytical precision of the measurements within 10% (95% confidential interval). All measured 137Cs concentrations were decay-corrected to their sampling date. Moreover, the results obtained in this study were also normalized by their initial average 137Cs inventory in the catchment (D, Bq m−2) to eliminate the effect caused by spatial differences.

As 137Cs concentration in the sediment sample depends on particle size19,20, we conducted a particle size correction for all measured data in Takase, Ukedo and Haramachi to eliminate this effect. The particle size distributions for dried SS samples were analysed using the laser diffraction particle size analyser (SALD-3100, Shimadzu Co., Ltd.). With the parameterized particle size distributions, the particle size correction coefficient (Pc) can be calculated by19:

Pc=(SsSr)v,

(10)

where Sr and Ss represent the reference and collected samples’ specific surface areas (m2 g−1). The exponent coefficient, v, is a fitting parameter associated with chemical and mineral compositions. In this study, the same parameters measured in the Abukuma River, the major river in the Fukushima area, were applied for Sr (0.202 m2 g−1) and v (0.65). The specific surface area for collected SS samples was estimated by the following equation under a spherical approximation20:

Ss=∑(6×ρ−1×d−1i×p−1i),

(11)

where ρ is the particle density and di and pi denote the ratio and diameter of the particle size fraction for particle i. Therefore, the 137Cs concentration corrected for particle size can be obtained by dividing the measured 137Cs concentration by Pc.

Considering that the decrease in particulate 137Cs concentration in a catchment was also affected by natural attenuation, there is a need to eliminate this effect from the declining trend of our observed 137Cs dataset to highlight the impacts of decontamination. The Ukedo and Takase are rivers surrounding the Niida River with similar contaminated situations. Our long-term 137Cs monitoring data from downstream of these two catchments showed that their 137Cs decline trends were relatively steady. Although there is a dam reservoir upstream of Ukedo, the 137Cs concentration observed both upstream and downstream showed a similar declining trend62. Therefore, the above evidence suggests that natural attenuation was the dominant factor controlling the 137Cs decrease in these two rivers. Here we assumed that the natural attenuation trend of 137Cs in the surrounding catchments (Ukedo and Takase) with little effect by decontamination was similar to that of the Haramachi catchment. Thus, we fitted their time change curves of 137Cs concentration (normalized by average 137Cs inventory of the corresponding catchment) using an exponential model. We then estimated the 137Cs concentration at the same sampling time as Haramachi in the two catchments by using the fitting models. Finally, we calculated the mean value of the two datasets and recalculated the effective half-life (Teff = ln(2)/λ; λ is the fitting exponential term) of the natural attenuation by the exponential model.

The 137Cs flux (LCs, Bq) for each monitoring site was estimated by the product of the SS flux and the 137Cs concentration in the suspended sediment sample. We then took the sum over that year:

LCs=∑(Q×Css×C).

(12)

According to the law of error propagation, we considered the error from SS load and 137Cs measurement in the combined uncertainty assessment for 137Cs fluxes and found their values are all within 1.1% (95% confidential interval).

Using 137Cs as a tracer in estimating SS source contribution

Although 137Cs has been widely used in tracing sediment source, the spatial variability of the 137Cs deposition inventory in the Fukushima catchment hinders the estimation of the source contribution from a specific region. However, for the decontaminated catchments, as the 137Cs concentration in decontaminated soil was much lower than that in contaminated regions (for example, forested regions and the riverbank)11,13,63, the fluctuations in the particulate 137Cs concentration can help to identify the sediment from the decontamination regions. Specifically, we assumed that the particulate 137Cs concentrations in surrounding contaminated watersheds (that is, having similar land-use composition) follow a similar decline trend driven by natural reasons, while the decontamination-induced land-cover changes cause other sediment sources to mix with the original river SS and thus result in a deviation in observed 137Cs concentrations from this natural trend. Therefore, the relative contribution (RC) of the specific sediment source can be expressed as:

RC=(Cm−Cn)(Cs−Cn),

(13)

where the Cm is the measured 137Cs concentration and Cs and Cn represent the 137Cs concentration in a specific sediment source and the naturally varied 137Cs concentration at the same time as the measured 137Cs. For data comparability, all 137Cs concentrations presented here were corrected by their particle size and 137Cs inventory. We also excluded the samples with collection weights below 0.5 g from the calculations due to their high uncertainty in Pc measurement.

In this study, the specific sediment source is the decontaminated soil in the Niida River Basin where the 137Cs concentration was approximately 53.99 ± 40.90 Bq kg−1 (refs. 37,42; mean ± standard deviation, N = 8). The natural decline of the 137Cs concentration (that is, λ) was established using temporal variation in 137Cs data originating from the Ukedo and Takase rivers, which were scarcely influenced by decontamination. The first measured 137Cs data in Haramachi were set as the starting point of its natural decline curve. The total uncertainty for the contribution percentage of SS from the decontaminated regions was calculated by the propagation of error from each part with the uncertainties originating from the measured 137Cs concentration, 137Cs concentration in a specific source and the natural 137Cs concentration. For the uncertainty in the 137Cs concentration in decontaminated soil (Cs), we set the standard deviation as its error source, while the natural 137Cs concentrations were calculated by the propagation of the 95% confidential interval of the fitting curves.

Reporting summary

Further information on research design is available in the Nature Research Reporting Summary linked to this article.

Data availability

Ordered decontamination process data are available from http://josen.env.go.jp/plaza/info/weekly/weekly_190607.html. Particulate 137Cs monitoring data in Haramachi, Takase and Ukedo during 2012–2017 are available from: https://doi.org/10.34355/Fukushima.Pref.CEC.00014, https://doi.org/10.34355/CRiED.U.Tsukuba.00020 and https://doi.org/10.34355/Fukushima.Pref.CEC.00021. The rest of data presented in this study are available from the corresponding author upon request.

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Acknowledgements

We appreciate B. Matsushita for his valuable suggestions on satellite image processing and NDVI calculation, J. Chen for sharing the code for ESTARFM, J. Takahashi for sharing 137Cs in decontaminated soil data, H. Kato for his suggestions on presenting the results, S. Fujiwara for his assistance on calculating the precipitation erosivity factor, Y. Yamanaka and T. Kubo for their work on decontamination map development, field investigation and preliminary data analysis and Y. He and F. Yoshimura for their constructive suggestions on improving figure quality. We also acknowledge funding support from the commissioned study from the Ministry of Education, Culture, Sports, Science and Technology (MEXT) FY2011–2012, Nuclear Regulation Authority FY2013–2014, Japan Atomic Energy Agency-funded FY2015–2021, Grant-in-Aid for Scientific Research on Innovative Areas grant number 24110005, Grant-in-Aid for Scientific Research (A) 22H00556, Agence Nationale de la Recherche ANR-11-RSNR-0002 and the Japan Science and Technology Agency as part of the Belmont Forum.

Author information

Authors and Affiliations

  1. Center for Research in Isotopes and Environmental Dynamics, University of Tsukuba, Tsukuba, Japan Bin Feng, Yuichi Onda, Asahi Hashimoto & Yupan Zhang
  2. Institute of Environmental Radioactivity, Fukushima University, Fukushima, JapanYoshifumi Wakiyama
  3. National Institute of Technology, Tsuyama College, Tsuyama, JapanKeisuke Taniguchi

Contributions

B.F. and Y.O. conceived the study; B.F. performed the data evaluation and all analyses, interpreted the data, wrote the manuscript and prepared all figures and tables in close discussion with Y.O.; Y.O. provided funding support for the field monitoring and all needed resources; K.T. and Y.Z outlined the boundary of the decontamination regions and implemented the drone observations of the sites; and Y.W. and K.T. performed the field river monitoring and determined the particulate 137Cs concentration. B.F., A.H. and Y.Z. prepared all satellite images, ran the NDVI calculation and processed ESTARFM. All listed authors contributed to the editing of the manuscript and approved the final version.

Source: https://www.nature.com/articles/s41893-022-00924-6

July 16, 2022 Posted by | Fuk 2022 | , , , | Leave a comment

Where to in 2045? Contaminated Soil from the Nuclear Power Plant Accident: The Present Location of Interim Storage Facilities, Fukushima.

July 3, 2022
Contaminated removed soil and other materials generated by decontamination following the accident at TEPCO’s Fukushima Daiichi Nuclear Power Plant are temporarily stored at an interim storage facility adjacent to the plant. Decontamination outside of the difficult-to-return zones has been largely completed, and decontamination is also progressing in the specified restoration and rehabilitation base areas (restoration bases) within the difficult-to-return zones where evacuation orders are expected to be lifted this spring or later. However, there is no concrete plan for the decontamination of areas outside of the restoration centers that are difficult to return to, and there has been no progress in discussions regarding the removal of contaminated soil outside of Fukushima Prefecture. Eleven years after the accident, the problem of radioactive waste remains unresolved. (The problem of radioactive waste remains unresolved even 11 years after the accident.)

◆Total amount of contaminated waste is not foreseeable
 According to the Ministry of the Environment, the amount of contaminated soil generated by decontamination in areas other than the difficult-to-return zones is estimated to be 14 million cubic meters, an enormous amount equivalent to 11 times the size of the Tokyo Dome. The soil is scheduled to be delivered to an interim storage facility by March 2010. In the remaining difficult-to-return zones in the seven municipalities of Fukushima Prefecture, six municipalities (excluding Minamisoma City) have been designated as “specific restoration base areas (restoration bases)” where decontamination work will be carried out ahead of other areas. It is estimated that 1.6 to 2 million cubic meters of contaminated soil will be generated in the decontamination of the reconstruction bases.
 In addition, the government decided in August 2009 to lift the evacuation order for difficult-to-return zones outside of the restoration centers by decontaminating homes and other structures on request of those who wish to return. The Ministry of the Environment said, “We will proceed with the acquisition of land and the construction of storage facilities while keeping a close eye on the amount of soil that can be brought in. We do not know the maximum amount that can be brought in.

◆Unclear whether the waste will be transported out of Fukushima Prefecture
 As the name implies, storage at interim storage facilities is considered “temporary” for final disposal. The government has promised to remove the contaminated soil to a final disposal site outside of Fukushima Prefecture in 2045, 30 years after the storage began in 2015. However, it is not known whether there are municipalities that will accept the waste contaminated by the nuclear accident, and the candidate site has not yet been decided.
 In addition, three-quarters of the total amount of contaminated soil in storage currently contains less than 8,000 becquerels of radioactive cesium per kilogram of soil, which is the same level as that of the soil that is normally incinerated or landfilled. The government plans to reuse contaminated soil with less than 8,000 becquerels per kilogram in public works projects such as road construction. However, the use of contaminated soil is strongly opposed by local residents, and efforts to put this into practical use have run into difficulties. The Ministry of the Environment states that it will “continue its efforts to develop technologies and gain the understanding of related parties.

Interim storage facilities are located around the Fukushima Daiichi Nuclear Power Plant and cover an area of 1,600 hectares. Of the privately owned land, which accounts for about 80% of the total area, 93% has been acquired by the government. The delivery of contaminated soil generated outside of the difficult-to-return zone is expected to be completed by the end of FY2022.

福島第一原発を囲むようにして汚染土を一時保管する中間貯蔵施設が広がる=福島県大熊町で(2022年1月25日、本社ヘリ「おおづる」から伊藤遼撮影)

https://www.tokyo-np.co.jp/article/161520?fbclid=IwAR1aeeM_DVPdjUmckTFzItQfpsfj9wKIRu9IbxaiTzDwnqK50g3THWmCd_0

July 10, 2022 Posted by | Fuk 2022 | , , | Leave a comment

Evacuation of Okuma Town Lifted, a First in a Town where Fukushima Daiichi Nuclear Power Plant is Located

July 1, 2022
 At 9:00 a.m. on July 30, the evacuation order was lifted in Okuma Town, one of the hard-to-return zones still restricted due to radioactive contamination caused by the accident at TEPCO’s Fukushima Daiichi Nuclear Power Plant (Okuma and Futaba Towns, Fukushima Prefecture). Eleven years and three months have passed since the accident, and this is the first time that people have been able to live in the difficult-to-return zone in the municipality where the Fukushima Daiichi Nuclear Power Plant is located. The town is moving forward with the attraction of companies related to the decommissioning of the plant and the construction of housing, but it is not clear how many people will be able to live in the area.
 The reconstruction site is mainly located in the residential area around Ono Station on the JR Joban Line and covers approximately 860 hectares, or 10% of the town’s land area. At the time of the nuclear accident, more than half of the population (11,505) lived there. Even now, approximately 5,900 people are registered residents, accounting for 60% of the total. The town has set a target of 2,600 residents in five years.
 Mayor Atsushi Yoshida said at a crime prevention patrol ceremony held in front of Ono Station, “It takes time to get back to the bustling town we once were. We have finally made a start.
 In April 2019, the evacuation order will be lifted in the southwestern part of Okuma Town, where about 380 residents are now living after the entire town was forced to evacuate due to the nuclear accident.

Specified Reconstruction and Revitalization Zone (Reconstruction base): A zone designated by the government after the Fukushima Daiichi Nuclear Power Plant accident as a “difficult-to-return zone” with high radiation levels, where government funds are being used to decontaminate the area in advance to enable residents to resume their lives. Of the seven municipalities in Fukushima Prefecture that remain in the difficult-to-return zones, six, with the exception of Minamisoma City, are located in these zones. The reconstruction base in Katsurao Village was lifted on June 12. The base in Futaba-cho, where the Fukushima Daiichi Nuclear Power Plant is located, is expected to be lifted in July or later.


◆There are many issues to be addressed, and the future will be tough.
 In Okuma Town, Fukushima Prefecture, where the evacuation order has been lifted, there are still some areas that have not been fully decontaminated, and some houses that have not been demolished and decontaminated yet. The situation remains inconvenient with no stores or hospitals, and residents who wish to return to their homes said, “There are a lot of issues. The future will be tough,” said one resident.
 About 6 km southwest of the Fukushima Daiichi Nuclear Power Plant. Mitsuhide Ikeda, 61, a part-time farmer, keeps 17 head of cattle in his pasture. On March 30, while feeding his cows with his wife Mikiko (64), Ikeda said, “I am happy to be able to go back to my home freely. I hope to resume livestock farming someday and also produce rice, vegetables, and fruits to show that it is possible to grow food in the area that was once a hard-to-return zone.

Mitsuhide Ikeda, who said he wants to return to livestock farming in Okuma, Fukushima Prefecture, on March 30.

Eleven years ago, on the morning of March 12, Ikeda and his wife refused to dispose of their cattle, even after the sudden evacuation, saying, “We cannot take away the lives of our cows, our precious family members who have supported our lives. Once they caught the cows that had fled, they continued to care for them while commuting from Hirono Town, Fukushima Prefecture, where they had evacuated from, about 25 km south of the town.
 Two years ago, he built an office where he can sleep on the site of his former home adjacent to the pasture, but even after the evacuation order was lifted, he continues to commute from Hirono Town. Even after the decontamination of his property, he found areas where the radiation level was 15 microsieverts per hour, well above the government’s long-term target of 0.23 microsieverts per hour, and had to have the area re-decontaminated. There were many such places throughout the neighborhood. Mitsuhide said, “The government could have bought up all the areas with high radiation levels and not decontaminated them.
 Mikiko does not want to live in Okuma because “shopping is inconvenient. Mitsuhide also said, “There is no one around for hundreds of meters, so when something happens, there is no one to shout out. It would be difficult to live there right now,” he spilled. Still, he is determined to fulfill his desire to be a cattle breeder on his ancestral land.


◆It’s just a transit point
 A woman, 60, who evacuated to Iwaki City, Fukushima Prefecture, feels that the lifting of the evacuation order is “just a passing point. After her house was placed in a recovery center, she asked the town what would happen to her house after the evacuation order was lifted, but she did not know.
 I couldn’t see what was going to happen to the town,” said the woman. Her house has been demolished, but the surrounding area has been ransacked by burglars and animals, and there are still buildings that have not been decontaminated. I like Okuma because I can feel the four seasons and smell the grass being cut,” she said. But even if I was told I could go home, I would not be able to lead a settled life in a place where the living environment is not well maintained.”
 The woman would like to build a house and live with her husband if the town’s environment is improved, but she cannot make up her mind right now. In a survey of residents’ intentions, 20% said they could not decide whether or not to return, but these people are the most likely candidates to come back. If we don’t take good care of them, they won’t come back.
https://www.tokyo-np.co.jp/article/186757?fbclid=IwAR1u_nJYuzfyBZH8Odmy_i0qmX4AWdYsaBiAkFpCud4I7HbevwaFA7efvxE

July 3, 2022 Posted by | Fuk 2022 | , , | Leave a comment

Japan OKs return to nuclear plant host town for 1st time in 11 yrs

Photo taken June 16, 2022, shows a zone in Okuma, Fukushima Prefecture, specified as a reconstruction and revitalization base, where an evacuation order will be lifted at 9 a.m. June 30. (Kyodo)

June 28, 2022

The government decided Tuesday to lift an evacuation order on part of a town hosting a crippled nuclear power plant in Fukushima Prefecture, allowing residents to return home for good this week for the first time since the March 2011 earthquake, tsunami and nuclear disaster.

Restrictions in a zone specified as a reconstruction and revitalization base in Okuma will be lifted at 9 a.m. Thursday, the first such case for a municipality hosting Tokyo Electric Power Company Holdings Inc.’s Fukushima Daiichi plant in northeastern Japan.

“Ending restrictions on an area, which used to be downtown (Okuma) before the disaster, will be a significant first step in reconstruction,” Economy, Trade and Industry Minister Koichi Hagiuda said.

“We will create an environment where residents can return home without worries,” Hagiuda said at a press conference.

Restrictions in the specified reconstruction and revitalization base zone of the town of Futaba, which also hosts the Fukushima Daiichi plant, are also expected to end soon.

Okuma will be the second municipality in Fukushima Prefecture, after the village of Katsurao, to see people coming back to an area once designated as difficult to return to due to high levels of radiation.

Restrictions in part of the village were lifted on June 12.

With decontamination work reducing radiation levels and infrastructure being prepared in Okuma, restrictions will end in the 8.6-square-kilometer area that was once the center of the town.

Residents have been able to stay overnight in the area since December in preparation for their full-scale return.

A total of 5,888 people in 2,233 households, accounting for about 60 percent of the town population, were registered as residents of the area as of Monday, according to the Okuma town government.

Three other municipalities where residents are still not allowed to return — Tomioka, Namie and Iitate — are expected to see restrictions lifted around next spring.

https://english.kyodonews.net/news/2022/06/e96af5c6ecfb-japan-oks-return-to-nuclear-plant-host-town-for-1st-time-in-11-yrs.html

July 3, 2022 Posted by | Fuk 2022 | , , | Leave a comment

Govt. to lift evacuation order for part of Fukushima’s Okuma Town

June 28, 2022

The Japanese government has officially decided to lift its evacuation order in part of Fukushima Prefecture’s Okuma Town.

About 60 percent of Okuma Town was designated as a “difficult-to-return” zone after the 2011 accident at the Fukushima Daiichi nuclear power plant. The plant is located in the town.

The evacuation order will be lifted in about 20 percent of Okuma Town’s “difficult-to-return” zone on Thursday. The decision was made on Tuesday.

The government decontaminated the area after it was designated as a special zone for reconstruction and revitalization.

The area will be the second “difficult-to-return” zone that residents can go back to.

The government made a similar decision for part of Katsurao Village earlier this month. Katsurao Village is located near the Fukushima Daiichi plant.

https://www3.nhk.or.jp/nhkworld/en/news/20220628_19/

July 3, 2022 Posted by | Fuk 2022 | , , | Leave a comment

Don’t Evacuate Evacuees to National Public Service Housing” Support Groups Meet

June 14, 2022

In response to the Fukushima prefectural government’s decision to file a lawsuit demanding compensation from some evacuees who continue to live in the national public employee dormitories in the Tokyo metropolitan area, a support group for the evacuees held a press conference and appealed, “The prefectural government must not evict the evacuees with the help of the judicial system. The Fukushima Prefectural Government and other organizations have stated that the prefectural government should not use the power of the judiciary to evict evacuees.

According to Fukushima Prefecture and other organizations, 26 families who voluntarily evacuated from outside the evacuation zone after the nuclear accident are still living in the national public employee dormitories in the Tokyo metropolitan area, even after the free provision of rooms ended at the end of March 2009. The provision of free housing has been terminated at the end of March 2009.

Of these, 11 households living in national public employee dormitories in Tokyo and Saitama prefectures are suing the prefectural government for approximately 11 million yen in damages for emotional distress caused by being asked to pay twice the rent and being contacted by relatives to move out. They have filed a lawsuit with the Tokyo District Court seeking approximately 11 million yen in damages.

The prefectural government has decided to submit a proposal to the June meeting of the prefectural assembly to demand that 10 of the 11 households suing the tenants vacate their rooms, claiming that it is difficult to settle the matter through negotiation. The prefectural government has decided to submit a proposal to the June regular meeting of the prefectural assembly demanding that 10 of the 11 households who filed the suit vacate their rooms.

In response to this, a support group for the evacuees held a press conference at the prefectural government office on June 14, and reported that many of the evacuees from the national public employee dormitories are elderly singles or part-time workers, and that it is difficult for them to move out, or that they have asked the prefectural government to allow them to stay at the dormitories until they can find a new place to live with the stipulated rent. However, the prefectural government refused and demanded compensation for damages.

He then said, “It is unacceptable for the prefectural government to evict evacuees from their homes with the help of the judiciary,” and appealed to the prefectural assembly to carefully deliberate on the proposal and reach a just conclusion.

https://www3.nhk.or.jp/lnews/fukushima/20220614/6050018928.html?fbclid=IwAR0epeFhn3Yf7y_gqidVG3JRviCFJvbb6tOEpTGF9g5a01Xr9gkX2mLy9hE

June 18, 2022 Posted by | Fuk 2022 | , , | Leave a comment

Japan’s Fukushima village residents allowed to return 11 years after nuclear disaster – but do they want to?

Restrictions lifted for some residents in Fukushima prefecture, more than decade after the nuclear disaster, but many people are still worried

It’s first time restrictions removed to allow people to live again in ‘difficult-to-return’ zone; government says radiation levels have been reduced

Workers open a gate in Katsurao, Japan, as evacuation orders are lifted for part of the village, near the crippled Fukushima Daiichi nuclear power plant, allowing residents to move back into their homes more than a decade on from the March 2011 disaster.

12 June, 2022

Residents from part of Katsurao village in Fukushima Prefecture can move back into their homes again more than a decade on from the March 2011 nuclear disaster that followed an earthquake and tsunami, after evacuation orders were lifted on Sunday morning.

It is the first time restrictions have been removed to allow residents to live again in part of the “difficult-to-return” zone once expected to stay closed far into the future due to high radiation exposure.

The government decided on June 3 to end restrictions for the 0.95-square-kilometre area after determining decontamination had reduced radiation levels, and that infrastructure was in place to support habitation.

But while the government has poured funds into decontamination and infrastructure development for zones known as “specified reconstruction and revitalisation bases” which are earmarked for reopening, the intervening 11 years have depressed residents’ desire to return to their homes.

In the part of Katsurao’s Noyuki district where restrictions have been lifted, just four of the 30 households comprising 82 people intend to return, according to the local government.

Amid rainy weather, an official from the central government’s nuclear emergency response headquarters declared the area reopened at 8am. After the gate blocking the road was opened, a police car and other vehicles quickly began patrols of the area.

Katsurao Mayor Hiroshi Shinoki indicated he was considering bringing back residents through revitalising local agriculture, the area’s key industry.

“This is one milestone,” he said. “It is our duty to work to try to bring things back as much as we can to how they were 11 years ago.”

But Fujio Hanzawa, a 69-year-old resident who was quick to revisit his home, spoke carefully when asked about the reopening. “I’m glad I can return without limits, but I’m still 80 per cent concerned. There are issues outstanding, like the unfinished decontamination of the mountain.”

Around 337 square kilometres of land in seven Fukushima municipalities remain subject to the difficult-to-return zone classification. Of those, a total of just 27 square kilometres in six of the same municipalities comprise specified reconstruction and revitalisation base zones.

Apart from Katsurao, the towns of Futaba and Okuma – the latter being home to the crippled Fukushima Daiichi nuclear power plant – are expected to see restrictions partially lifted sometime this month or later, with another three municipalities scheduled for next spring. A specific timetable for areas outside the specified reconstruction bases has not been reached.

Katsurao was made entirely off-limits following the nearby nuclear power plant’s meltdown in the aftermath of the March 2011 earthquake and tsunami.

https://www.scmp.com/news/asia/east-asia/article/3181426/japans-fukushima-village-residents-allowed-return-11-years

June 18, 2022 Posted by | Fuk 2022 | , , | Leave a comment

Government OKs reopening of Fukushima village section to residents in June

Decontamination work is conducted in the village of Katsurao, Fukushima Prefecture, in November 2018

June 3, 2022

Fukushima – More than a decade since the March 2011 nuclear disaster, some registered residents of part of a Fukushima village made off-limits by high radiation levels can finally return home after the government decided Friday to lift evacuation orders on June 12.

While some areas around stations and rail tracks had their so-called “difficult-to-return” zone classification lifted, it is the first time for the classification to be lifted to host permanent residents again.

A 0.95 square kilometer part of Katsurao, located near the defunct Fukushima No. 1 nuclear power plant, will have the designation lifted, the government’s nuclear emergency response headquarters and the Reconstruction Agency agreed in a joint meeting.

The move comes after national and local governments decided in May that the area’s radiation decontamination and infrastructural developments had progressed enough to reopen.

“This is a big step toward the restoration of the village,” said Mayor Hiroshi Shinoki in a statement. “The lifting is not a goal, but a start.”

The entirety of Katsurao became off-limits after the nuclear crisis triggered by an enormous earthquake and tsunami on March 11, 2011, with evacuation orders for most of the village lifted on June 12, 2016.

Of the 30 registered households and 82 residents in the relevant part of Katsurao, just four households totaling eight people have expressed an intention to return, according to the village government.

Currently, around 337 sq. km of land in six municipalities of Fukushima Prefecture, including Katsurao, Okuma and Futaba, is still subject to the difficult-to-return zone classification.

At Friday’s meeting, Prime Minister Fumio Kishida said he intends to “move ahead with work to lift restrictions and further accelerate Fukushima’s recovery.”

Among the five other Fukushima municipalities inside the zone, Futaba and Okuma are set to have restrictions partially lifted from June onward, while the other three can expect partial removals in spring 2023.

However, more than 90% of the difficult-to-return zone in the prefecture will remain under the classification, and there is no concrete timetable for when it will be completely accessible again.

https://www.japantimes.co.jp/news/2022/06/03/national/fukushima-village-residents-return/?fbclid=IwAR1dC6AUO7mneslC3NsFAK0Gg08TXj2LeFTEjE7UJuEG4OElfjU-DYT-eU0

June 13, 2022 Posted by | Fuk 2022 | , , | Leave a comment

Areas reopening after Fukushima nuclear disaster need sustained gov’t support

June 10, 2022

Evacuation orders that have been in place since the 2011 Fukushima Daiichi Nuclear Power Station disaster are set to be lifted in part of the Fukushima Prefecture village of Katsurao, one of the so-called difficult-to-return zones, on June 12.

Difficult-to-return zones, which people are forbidden from entering in principle due to high radiation levels, have been left behind in the recovery process. The latest move marks the first time that people will be able to live in one of these areas since the meltdowns triggered by the March 2011 Great East Japan Earthquake and tsunami.

The central parts of six difficult-to-return towns and villages including Katsurao have been designated as “zones for reconstruction and recovery,” and the national government has been carrying out decontamination work there. The part of the village of Katsurao set to reopen for living is one of such zones, finally marking a step forward more than 11 years after the accident.

However, of the 82 people in 30 households registered in that part of Katsurao, at this stage only eight people in four households have expressed their intention to return.

Evacuation orders were lifted in 2016 for other parts of Katsurao that fell outside the difficult-to-return zone, five years after the onset of the disaster. Another six years have passed since then, and residents have apparently become hesitant to return.

Through next spring, it is expected to become possible for people to permanently return to designated reconstruction and recovery zones in five remaining towns and villages including the towns of Futaba and Okuma, which the crippled nuclear power station straddles.

Many residents, however, are reluctant to return as those areas face an uncertain future. While local bodies are planning to secure medical care and attract commercial facilities into the areas, there is a need to steadily prepare such a living environment.

Besides worries about the future, an additional source of concern for people is that decontamination work in areas outside the specified reconstruction and recovery zones has yet to commence.

The government promised to create an environment enabling all residents wanting to return to do so in the 2020s. But the only places outside the restoration and recovery zones that the government has decided to decontaminate are returning residents’ homes and their vicinities. It has not revealed how it plans to handle other land and homes.

If the scope of decontamination work is not fixed, there will likely be many residents unable to decide whether they can return with peace of mind. The government needs to quickly present a course of action.

The road to recovery of the difficult-to-return zones is still far off. An official at Katsurao Murazukuri Kosha, a public corporation that is promoting the revival of the village, stressed, “First, it’s important to properly support the lives of people who have returned. We want to move forward one step at a time from there.”

The government has a responsibility to accomplish the revitalization of Fukushima. It must listen to the voices of residents, and continue to offer sustained support.

https://mainichi.jp/english/articles/20220610/p2a/00m/0op/013000c

June 13, 2022 Posted by | Fuk 2022 | , , | Leave a comment

Magnitude 6.0 quake shakes Japan’s east and northeast

The epicenter of the earthquake that occurred on May 22 at 12:24 p.m. is located offshore in Ibaraki Prefecture

May 22, 2022

TOKYO (Kyodo) — An earthquake with a preliminary magnitude of 6.0 struck Fukushima and other prefectures in Japan’s east and northeast on Sunday, but there was no threat of a tsunami, the country’s weather agency said.

There were no immediate reports of injuries or serious property damage following the quake, which occurred around 12:24 p.m.

The quake’s magnitude was later revised upward from the initial estimate of 5.8, the Japan Meteorological Agency said.

The quake registered a lower 5 on the Japanese seismic intensity scale of 7 in Fukushima’s Iwaki city, according to the agency. Its focus was at a depth of about 30 kilometers in the Pacific off Ibaraki Prefecture.

The quake registered 4 in some other parts of Fukushima and 3 in the neighboring prefectures of Miyagi, Yamagata, Ibaraki, Niigata and Tochigi.

No abnormalities were found at the Tokai No. 2 nuclear power plant on the coast of Ibaraki or at the Fukushima Daiichi and Daini nuclear power plants, their operators said.

There were also no major transport disruptions. JR East said it briefly suspended services on a section of the Tohoku Shinkansen bullet train line between Fukushima and Miyagi prefectures.

https://www.japantimes.co.jp/news/2022/05/22/national/earthquake-ibaraki-fukushima/

May 29, 2022 Posted by | Fuk 2022 | , | Leave a comment

Seismic intensity of 5 on the Iwaki City, Fukushima Prefecture, Japan; operation suspended between Takahagi and Tomioka on Joban Line

May 22, 2022

At around 0:24 p.m. on March 22, an earthquake centered off the coast of Ibaraki Prefecture hit Iwaki City, Fukushima Prefecture, with an intensity of just under 5 on the Japanese seismic scale, while Koriyama City, Hirono Town, Tomioka Town, Namie Town, and other areas in Fukushima Prefecture registered an intensity of 4 on the Japanese scale. According to the Japan Meteorological Agency, the epicenter was about 5 km deep, and the magnitude of the quake was estimated at 6.0. There is no concern of a tsunami from this quake.

 According to East Japan Railway Company, the earthquake caused a temporary power outage on the Tohoku Shinkansen Line between Shin-Shirakawa and Shiroishi Zao, suspending operations, which resumed at 0:32 pm. The line was reportedly delayed by up to 10 minutes.

 Also, due to the earthquake, operation is suspended on the Joban Line between Takahagi (Takahagi City, Ibaraki Prefecture) and Tomioka (Tomioka Town, Fukushima Prefecture) on the up and down lines.
https://www.asahi.com/articles/ASQ5Q44YWQ5QUTIL00F.html?fbclid=IwAR23WM3gBJHdz7AUbi7pmI1lkOKNgpPyNpvK_TRmjrqeTGOk52FCnPCen8w

May 22, 2022 Posted by | Fuk 2022 | , , | Leave a comment