Nuclear Accident Research Articles

Robotics uncharted: When hazardous-duty robots met the Fukushima nuclear disaster (2011–2015)

The Fukushima nuclear disaster of 11 March 2011, created a hazardous environment for both residents and rescue workers. The proficient use of robotic technology to assist with disaster mitigation and intense research into this genre of robotics had been proposed as a pivotal substitute for endangering disaster workers in disaster response. However, despite the high expectations and aspirations of Japan’s competitive robotics industry, the technological and political problems surrounding the use of robots were severe. Robot-enabled disaster management can only materialize through effective policy direction by the government. This paper explores the problems of using robots in disaster management since Japan’s launch of a nuclear disaster-response robot project in the 1980s.

Methodology for analyzing dose consequence using atmospheric dispersion code A2CDOSE

Abstract The experience of Fukushima brings out the importance of the emergency response plan during or after a severe nuclear power plant (NPP) accident. To deal with the accident emergency response situation, the National Atomic Research Institute (NARI) in Taiwan developed an emergent radiological dose evaluation system with the Central Weather Administration (CWA) called “A2CDOSE”. A2CDOSE can evaluate the eight-day projected dose after a nuclear accident and provide the predicted dose consequences for decision-making. Nevertheless, a source term generation method was still needed during the accident. This study chose MELCOR as the comparison target for the source term simulation issue with RASCAL. A MELCOR calculation of Maanshan NPP was built and a 5 % containment leakage was set for both MELCOR and RASCAL source term calculations. It seems the calculations of noble gases were consistent between MELCOR and RASCAL. However, the Cs-137 and I-131 calculated by MELCOR were twice compared to the RASCAL results, which may have a chance to cause different calculations of public protective actions during an accident. After the source term analysis, several atmospheric dispersion cases were simulated by A2CDOSE and RASCAL for further comparison.

Improving the estimation of direct release rates and transport processes from the Fukushima Daiichi Nuclear Power Plant accident using higher-resolution oceanic dispersion model

A series of accidents at the Fukushima Daiichi Nuclear Power Station (F1NPS), following the 11 March 2011 earthquake and tsunami, resulted in the release of radioactive substances into the ocean. In particular, the release of large amounts of radioactive caesium has damaged the fishing industry, leading to voluntary restrictions on fishing and shipping. Oceanic dispersion simulations based on estimates of the pathways and fluxes of radioactive materials provide useful information for assessing the environmental impacts and formulating measures to mitigate the effects of the accident. For the direct release rate from the F1NPS site, an estimation method was developed using the results from nearby monitoring, and the seawater exchange rate was estimated in target volume using a numerical simulation. However, the influence of volume on the seawater exchange rate was not considered. Appropriate volumes must be considered when estimating the effects of future accidents. In addition, the directional coastal transport was underestimated in the simulations of the F1NPS accident because of the low resolution. To estimate the pathways and fluxes of radioactive material to the ocean and understand the distribution of the concentration of radioactive material based on ocean dispersion simulations, a study was conducted using a higher-resolution model. The horizontal resolution of the conventional ocean dispersion model Regional Ocean Modelling System (ROMS), was increased from 1 km to 200 m. The optimal settings of the seawater exchange rate were investigated, and the radioactive caesium transport process in the coastal direction was more accurately reflected. We found that the conventional volume for determining the seawater exchange rate, including the locations of release sources and observation points, is optimal. The validity of this finding was confirmed using experimental equations from previous oceanic tracer release experiments. To estimate future release rates, it an appropriate volume must be defined, for example, depending on the distance between the locations of the release sources and the observation point. In addition, improvements in the accuracy of the simulation of the coastal transport process were observed owing to the higher resolution, which increased reproducibility. However, with a horizontal resolution of 200 m, problems with repeatability near the harbours arose. A higher resolution, achieved using nesting or other methods, would be desirable to deal with releases smaller than those in the F1NPS accident.

Polaritonic states trapped by topological defects

The miniaturization of photonic technologies calls for a deliberate integration of diverse materials to enable novel functionalities in chip-scale devices. Topological photonic systems are a promising platform to couple structured light with solid-state matter excitations and establish robust forms of 1D polaritonic transport. Here, we demonstrate a mechanism to efficiently trap mid-IR structured phonon-polaritons in topological defects of a metasurface integrated with hexagonal boron nitride (hBN). These defects, created by stitching displaced domains of a Kekulé-patterned metasurface, sustain localized polaritonic modes that originate from coupling of electromagnetic fields with hBN lattice vibrations. These 0D higher-order topological modes, comprising phononic and photonic components with chiral polarization, are imaged in real- and Fourier-space. The results reveal a singular radiation leakage profile and selective excitation through spin-polarized edge waves at heterogeneous topological interfaces. This offers impactful opportunities to control light-matter waves in their dimensional hierarchy, paving the way for topological polariton shaping, ultrathin structured light sources, and thermal management at the nanoscale.

A model to predict indoor concentrations and internal radiation doses of radioactive aerosols from nuclear accidents

Spread of radiation contaminations can be affected by several factors. Some of these factors were considered in previous articles. Those studies were based on some Computational Fluid Dynamic (CFD) schemes and gave good results for describing deposition and penetration of aerosol particles. In this paper, those CFD schemes are applied to set a model that can be used to calculate the indoor concentrations of the radioactive aerosols that release from nuclear accidents. The one of the Fukushima nuclear power plant (NPP) that took place in 2011 is taken as an example. Furthermore, the internal radiation doses caused by the intake of the radioactive aerosols are estimated. Considering in particular the radionuclide C137s, due to its very long half-life, the internal doses are calculated for the lungs and some of the surrounding vital organs. The radiation transport throughout the body is simulated by codes of the Monte-Carlo N-Particle simulation software, version 5 (MCNP5), with exploiting the human body representation by the phantom of the Oak Ridge National Laboratory-Medical Internal Radiation Dose (ORNL-MIRD). The results show a large spread of the radiation contaminations from outdoors to indoors, and that the whole-body annual dose from C137s is more than tenfold higher than the annual dose limit set by the International Commission on Radiological Protection (ICRP).

Quality and safety of products using GM soybeans in the diet of bulls

The production of high-quality and safe food products in areas contaminated by radiation due to the Chornobyl Nuclear Power Plant accident remains a pressing issue. The aim of this study was to determine the concentration and transfer factors of 137Cs, Pb, Cd, Cu, and Zn in bull products when including various high-protein feeds, such as narrow-leaved lupin and genetically modified soybean, in their diets. The study employed zootechnical methods (design and conduct of a scientific-economic experiment on animals), radiological and spectrometric methods (determination of the concentration of 137Cs, Pb, Cd, Cu, and Zn in feeds, longissimus dorsi muscle, liver, kidneys, and testes of bulls), and statistical methods. It was established that when using GM soybean in the grain mixture, the concentration of 137Cs in the muscle tissue of animals in Group II (experimental) decreased relative to the control by 2.57 Bq/kg, or by 40.5% with a statistically significant difference between groups (P > 0.99). Furthermore, the transfer factor of the radionuclide into the muscle tissue of animals in Group II compared to Group I also had 2.15% abs. lower. The content of Pb in the muscle tissue of bulls in both experimental groups exceeded the maximum permissible concentration by 2.52-2.78 times, while the concentration of Cd in the longissimus dorsi muscle and Cu in the liver of animals in Group II also exceeded sanitary-hygienic requirements by 10.0% and 2.0%, respectively. The introduction of 40% (by mass) of maize grain and 30% of GM soybean into the grain mixture instead of the same amount of wheat and lupin chop during the fattening of animals in the third zone of radioactive contamination contributed to significantly higher content and transfer of heavy metals into muscle tissue: Pb – by 10.3% and 0.10% abs., Cd – 10.0 and 0.03, Cu – 17.2 and 0.53, and Zn – by 17.2% and 2.40% abs. The results of the research can be used in agricultural enterprises and private households that produce livestock products in areas with a high anthropogenic load

Analysis of the Long-Term Interaction Between Molten Core and Dry Concrete at Fukushima Daiichi Unit 1

The latest investigations of Fukushima Daiichi Unit 1 have demonstrated that corium attack to the pedestal walls and pedestal floor has occurred in Fukushima Daiichi Unit 1 to a certain extent. The results of past analytical benchmarks, such as the Organisation for Economic Co-operation and Development (OECD)/Nuclear Energy Agency (NEA) Benchmark Study of the Accident at the Fukushima Daiichi Nuclear Power Plant (BSAF project), have agreed with this finding. However, the latest investigation does not show evidence of unlimited molten core–concrete interaction (MCCI), which is one of the main discrepancies from the BSAF project. More recently a MCCI benchmark has been launched in the context of the OECD/NEA project ARC-F (Analysis of Information from Reactor Building and Containment Vessels of Fukushima Daiichi Nuclear Power Station). In the benchmark, common geometry, boundary, and initial conditions have been selected among all the participants. The results show an improved agreement among different codes for what concerns overall erosion, corium temperature, and hydrogen generation, confirming that to some extent, the earlier scatter found in these variables came from differences in the MCCI scenario modeled by each partner. However, common unlimited erosion, not observed by onsite visual inspections, is still predicted. Understanding the origin of this deviation might provide insights into boundary conditions, model drawbacks, or ill-posed assumptions that might need to be revisited (e.g. interfacial temperature, effective heat transfer coefficients, concrete heat transfer). In this paper, a summary of the overall results and a discussion of modeling and boundary conditions is presented to disclose the results of the activity and the future steps to be taken in the OECD/NEA project FACE (Fukushima Daiichi Nuclear Power Station Accident Information Collection and Evaluation).

Embodying the nuclear: The moral struggle of family care in postfallout Japan

AbstractThis paper examines the moral struggle of family care by focusing on parents’ efforts to raise “healthy” children in irradiated environments of Fukushima following the 2011 Fukushima Daiichi nuclear disaster. Drawing on fieldwork between 2017 and 2020, it explores the lived experiences of primary caretakers, mostly mothers, as they strive to cultivate “health” in their children while negotiating conflicting logics of radiological exposure, risk assessment, and gendered childcare. Central to this endeavor is what I call an ethical labor of “balancing:” the daily negotiation between protecting children and allowing them to live fully in risk‐laden environments. Emphasizing intercorporeal and interpersonal aspects of embodied care, the paper examines the nuanced ways in which three mothers recalibrate notions of health, personhood, and responsibility to safeguard their children's everyday lives. Such notions of “health” carry significant implications for family dynamics amid the uncertainties of postdisaster life. By highlighting the critical role of family care in potentially stigmatizing environments, the paper advocates for developing frameworks that address the real‐life complexities of making life in an increasingly compromised world.

A novel strategy for iodine removal from nuclear reactor accidental gases: efficient adsorption of CH3I on the moderately hydrophobic modified silver-loaded zeolite under high temperature and humidity conditions

ABSTRACT Ensuring nuclear energy safety through effective gas emission filtration from nuclear reactor containment in accident scenarios is paramount. The efficacy of hydrophobic modified Ag-loaded zeolites for methyl iodide (CH3I) removal under challenging conditions of high temperature, humidity, and irradiation is studied in this work. Through hydrophobic modification of AgX zeolite with three different silane coupling agents, a series of modified zeolites with varied hydrophobicity levels is produced. The adsorption capabilities of these modified materials are assessed using a self-designed gas adsorption setup, focusing on CH3I removal from a gas mixture emblematic of nuclear accident environments. Results indicate that all hydrophobically modified zeolites exhibited superior CH3I removal rates compared to their unmodified counterparts, with the variant modified with 10% phenyltriethoxysilane achieving the highest removal rate of 99%. Additionally, zeolites modified with octyltrimethoxysilane demonstrate commendable irradiation resistance at a radiation dose of 4.2 × 105 Gy. The results suggest that optimally hydrophobically modified AgX zeolites hold significant promise for filtering gases containing radioactive iodine, offering novel insights for the advancement of adsorbent materials in nuclear reactor containment discharge systems.

Resilience-based seismic design for nuclear island building: An innovative hybrid passive control system

The Fukushima nuclear incident has heightened global concerns about the safety of nuclear facilities, the imperative to enhance the seismic resilience of nuclear power plants (NPPs) has become a pivotal aspect of nuclear safety. This study introduces an innovative hybrid passive control system that integrates three-dimensional (3D) base isolation technology with periodic isolation walls, aiming to bolster the seismic resilience of NPPs against very rare earthquakes. Furthermore, a complete and viable computational procedure was developed to study the nonlinear soil-structure interaction effects with high-precision wave motion analysis. Finally, the efficacy of the innovative control system to improve the seismic resilience of large-scale nuclear island buildings situated on non-rocky sites was assessed. The findings reveal that the system significantly mitigates the distribution of damage to NPPs during very rare earthquake scenarios. Compared to non-isolated NPP, the adoption of a hybrid passive control system reduces structural damage dissipation energy by 97.73 %. The system augments the effectiveness of 3D base isolation technology in reducing dynamic responses; specifically, the floor response spectra at the top position of the nuclear island building in the X, Y, and Z directions were lowered by 62.33 %, 52.03 %, and 84.12 %, respectively. Moreover, the system considerably reduces the deformation of the 3D isolation bearings. The innovative hybrid passive control system helps to enhance the seismic resilience of NPPs.

Serum miR-192–5p is a promising biomarker for lethal radiation injury

In the event of a nuclear or radiation accident, rapid identification is required for those who exposed to potentially lethal dose irradiation. However, existing techniques are not adequate for the classification of lethal injury. Several studies have explored the potential of miRNAs as biomarkers for ionizing radiation injury, however, there are few miRNAs with specific expression for lethal radiation injury. Therefore, the aim of this study was to screen and validate the possibility of serum miRNAs as biomarkers of lethal radiation injury. We found the specific expression of mmu-miR-374c–5p / mmu-miR-194–5p on first day and mmu-miR-192–5p / mmu-miR-223–3p on third day in the mouse serum only under 10 Gy irradiation by miRNA sequencing and all significantly correlated with lymphocyte counts by Pearson’s correlation analysis. In addition, it was found that among the 4 candidate serum miRNAs, only highly-expressed mmu-miR-192–5p in mouse serum irradiated at lethal doses was returned to sham-like expression levels at 3 days post-irradiation with amifostine pretreatment and closely correlated with survival rate. We demonstrated for the first time that mmu-miR-192–5p screened from lethally irradiated mice sera can be used as a potential biomarker for lethal irradiation injury, which will be helpful to improve efficiency of medical treatment to minimize casualties after a large-scale nuclear accident.

Metal-organic cages for efficient capture and convenient detection of iodine from vapor and aqueous solutions

In the pursuit of advancing radioactive waste management and mitigating the risks associated with nuclear accidents, the development of effective adsorbents for the removal of radioactive iodine from the environment is paramount. This study presents the synthesis and characterization of two metal–organic cages (MOCs) tailored for the efficient adsorption of volatile iodine vapor and iodine from aqueous solutions. The prepared MOCs exhibited efficient adsorption capacities for iodine vapor and iodine in water. Experimental and theoretical analyses underscored the significance of hydrophobic and electrostatic interactions in augmenting the iodine adsorption efficacy from aqueous solutions, providing valuable insights into the design of high-capacity iodine adsorption materials for aqueous environments. Furthermore, MOC-coated test strips were developed, enabling rapid, convenient, and sensitive detection of iodine vapor and iodine in aqueous solutions through the integration of fluorescent elements. To the best of our knowledge, this study presents a pioneering example of MOCs proficient in both adsorbing and detecting iodine vapor and iodine in aqueous solutions.

Comparison of TL characteristics of natural quartz and zircon.

The dosimetry of different minerals is carried out to investigate the dose received by the population in case of a nuclear accident. Retrospective dosimetry is a field where there is a continuous search to find new materials. Beach sand minerals, namely quartz and zircon, were exposed to beta and gamma radiation and studied separately. A comparison of the thermoluminescence (TL) output of different peaks of quartz for beta and gamma was studied. Comparison of quartz peaks with the TL output of zircon peaks was carried out. TL output for a constant dose of gamma is always higher compared to the TL output received due to beta.

Literature survey and analysis of phytoremediation strategies for Cs-137 decontamination

Phytoremediation has become a sustainable solution for mitigating cesium-137 (Cs-137) contamination and has been implemented in areas affected by the Chernobyl and Fukushima nuclear disasters. Despite the absence of nuclear power plants in Indonesia, incidents of Cs-137 contamination have been reported in Batan Indah Housing Complex, emphasizing the need for effective decontamination techniques. The aim of this study was to analyze the bibliometric characteristics of research works on phytoremediation in addressing Cs-137 contamination during the last ten years (2013–2022) by foreign and Indonesian authors. This research is important both globally and in specific contexts, such as Indonesia, particularly in the context of policy and practical applications. For example, when facing issues like Cs-137 decontamination in the BATAN Indah area, the research can have local relevance and contribute to solving immediate problems. This study utilized the Scopus database and retrieved 2,123 article titles within this topic over the last decade. Several indicators were used to examine the publications: productivity of authors, collaboration between countries, top-cited articles, keywords analysis, and publication trends. The results show that the number of publications fluctuated over previous decade with an average publications age of 5.54 years. Onda Y from the University of Tsukuba, Tsukuba, Japan become the most prolific and collaborative author. Japan being the most productive and collaborative country, while Indonesia ranked 42nd with only 9 publications regarding the topics. The bibliometric analysis provides a foundation for understanding the development of science on this topic and uncovers that there is still plenty of space to conduct phytoremediation research in Indonesia, especially for Cs-137 contaminated soils, which have increased over the years.

Overview of marine radionuclides from sampling to monitoring

Abstract Radioactive materials may contain primordial radionuclides, and radionuclides of anthropogenic, nuclear accident, and waste disposal which are present in marine environments. This review explores various approaches for the effective sampling and detection of marine radionuclides. The different types of samples that can be collected, including water, sediment, biota, and suspended particulate matter are discussed. Additionally, this paper discusses the various analytical techniques employed for radionuclide detection, such as gamma spectrometry and radiochemical separation. The review emphasizes the importance of choosing appropriate sampling and detection methods based on the specific radionuclides, environmental conditions, and the desired level of sensitivity. It also highlights the challenges associated with their sampling and detection in complex marine environments. These include low radionuclide concentrations, interference from natural matrices, and contamination risks.

Orbital-Rail-Type Automatic Inspection Device for Pipeline Welds Using Radiation Dose Prediction Results from FLUKA Simulation

Pipeline welds typically do not have secondary reinforcement, rendering welds highly vulnerable to leakage accidents caused by the movement of gases or liquids. Therefore, identifying internal defects in welds through radiographic testing (RT) is critical for a visual and quantitative evaluation of weld defects. In this study, we developed a device that can automatically inspect the circumferential connection between pipes by applying a digital radiography testing (DRT) technique that can convert radiation signals into real-time electrical signals by using a digital detector array (DDA). Gamma rays were used to minimize spatial constraints in the inspection environment and optimization was performed to satisfy quality requirements set by international standards. Furthermore, FLUKA simulation was performed to predict radiation intensity for accurate radiation leakage identification to enable the shielding design to be supplemented with lead rubber. This measure considerably reduces the safe distance for radiation leakage during field testing. The results confirmed the feasibility of a novel automated inspection technique that integrates automatic inspection devices and ensures safety using radiation, the byproduct of which is a hazardous material.

A reconstruction method of stress fields, bending moments and wave parameters for floating nuclear power plants through regular wave identification

Floating nuclear power plants (FNPPs) have the potential to supply abundant electricity, hot water, and freshwater resources for offshore islands and offshore oil and gas extraction platforms. However, the consequences of a nuclear reactor accident can be extremely serious. In addition, there may be many uncertain factors in the actual operation of FNPPs. These factors lead to higher structural safety requirements. So， developing more scientific structural monitoring methods is an effective way to enhance the structural safety of FNPP. Traditional hull monitoring schemes can only track bending and torsional forces on specific cross-sections, failing to identify the overall stress field of the entire vessel structure. The paper proposes a reconstruction method for the stress field, bending moment distribution, and wave parameters of FNPP using regular wave identification. Initially, irregular waves are decomposed into a linear combination of multiple regular waves with different amplitudes and frequencies. Subsequently, the strains induced by these regular waves on the FNPP are utilized as basic functions to establish a mathematical model for reconstructing the stress field. The stress field, bending moment distribution, and wave parameters of the FNPP can be reconstructed by identifying the combination coefficients of the regular wave loads. The ill-posedness of the mathematical model for stress field reconstruction has the potential to significantly impact the accuracy of the stress field reconstruction, which was addressed by optimizing the sensor installation position in this study. Meanwhile, the optimization of the sensor installation position greatly reduces the dimensionality of mathematical models. Finally, a numerical study, i.e. FNPP being designed by China, was used to validate the accuracy of the proposed stress field reconstruction algorithm. The reconstructed stress field of the FNPP closely matched the original stress distribution under various irregular wave conditions.

Radioactive Attenuation Using Different Types of Natural Rocks.

Humans benefit from nuclear technology, but it also generates nuclear radiation that is bad for both the environment and human health. The serious issue of radiation leakage affects many technological applications. Shielding is required to protect both users and the environment from negative side effects. This work describes the radioactive attenuation properties of some natural rocks, such as claystone, bentonitic claystone, bentonitic shale, sandstone, and basalt using a NaI(Tl) detector. The mass attenuation coefficients μm of these rocks at various photon energies, half-value layer (HVL), tenth-value layer (TVL), and mean free path (MFP) were determined. The validation of obtained values of μm was carried out against the theoretical calculations from the XCOM program, and the correlation factor and relative deviation between the two methods were evaluated. It was noted that basalt samples exhibit superior shielding parameters when compared to other rock samples. Also, the concentrations of naturally occurring radioactive elements (238U, 226Ra, 232Th, and 40K) were measured, allowing for the calculation of environmental hazard indices and assessment of attenuation (%) efficiency for certain natural rocks, such as bentonite, sandstone, and basalt. The results revealed that increasing the thickness of Basalt-AZ from 1.5 cm to 2 cm results in an approximate 11% rise in attenuation percentage, with values reaching 77.12%, 67.2%, 67.65%, and 59.8% for NMA-U, IAEA-Th, IAEA-Ra, and IAEA-K, respectively.

Consequences of ionizing radiation exposure to the cardiovascular system.

Ionizing radiation is widely used in various industrial and medical applications, resulting in increased exposure for certain populations. Lessons from radiation accidents and occupational exposure have highlighted the cardiovascular and cerebrovascular risks associated with radiation exposure. In addition, radiation therapy for cancer has been linked to numerous cardiovascular complications, depending on the distribution of the dose by volume in the heart and other relevant target tissues in the circulatory system. The manifestation of symptoms is influenced by numerous factors, and distinct cardiac complications have previously been observed in different groups of patients with cancer undergoing radiation therapy. However, in contemporary radiation therapy, advances in treatment planning with conformal radiation delivery have markedly reduced the mean heart dose and volume of exposure, and these variables are therefore no longer sole surrogates for predicting the risk of specific types of heart disease. Nevertheless, certain cardiac substructures remain vulnerable to radiation exposure, necessitating close monitoring. In this Review, we provide a comprehensive overview of the consequences of radiation exposure on the cardiovascular system, drawing insights from various cohorts exposed to uniform, whole-body radiation or to partial-body irradiation, and identify potential risk modifiers in the development of radiation-associated cardiovascular disease.

Impacts of farmland decontamination on 137Cs transfers in rivers after Fukushima nuclear accident: Evidence from a retrospective sediment core study

Following the Fukushima Daiichi Nuclear Power Plant disaster in March 2011, the Japanese government initiated an unprecedented decontamination programme to remediate 137Cs-contaminated soils and allow population return. This programme involved the removal of topsoil under farmland and residential land, and its replacement with “fresh soil” composed of granitic saprolite. However, decontamination was limited to these two land uses, without remediating forests, which cover 70 % of the surface area in the affected region. In this unprecedented context, the specific impact of this unique decontamination programme on 137Cs transfers in river systems remains to be quantified at the catchment scale. In this study, based on the analysis of a sediment core collected in June 2021 in the Mano Dam reservoir draining a decontaminated catchment, the effects of soil decontamination on particle-bound 137Cs dynamics and sediment source contributions in response to a succession of extreme precipitation events were retrospectively assessed. The sequence of sediment layer deposition and its chronology were reconstructed through the analysis of several diagnostic properties (organic matter, elemental geochemistry, visible colourimetry, granulometry) and contextual information. During abandonment (2011–2016), cropland contribution decreased (31 %). Concurrently, 137Cs activity and deposition flux decreased (19 and 29%year−1, respectively). Following decontamination (2017), sediment transfer increased (270 %) in response to increased contributions from decontaminated cropland and “fresh soil” (625 % and 180 % respectively). Meanwhile, forest contributions remained stable. In contrast, 137Cs activity dropped (65 %), although 137Cs deposition flux remained constant. Forests acted as a stable source of 137Cs. Accordingly, 137Cs deposition flux after decontamination (2016–2021) was similar to that observed during the 5-years period of land abandonment (2011–2016), as a result of the regrowth of spontaneous vegetation over farmland, protecting soil against erosion. Future research should further investigate the impact of longer land abandonment that prevailed in some regions decontaminated lately on the 137Cs fluxes in the rivers.