Journal of environmental radioactivity最新文献

{"title":"Investigation on the reactive transport characteristic of uranium-bearing sandstone during the in-situ leaching mining uranium","authors":"Xuebin Su ,&nbsp;Junlin Mao ,&nbsp;Tong Zhang ,&nbsp;Xin Yang ,&nbsp;Yihan Yang ,&nbsp;Chuanfei Zhang ,&nbsp;Peng Qiao ,&nbsp;Bingzhang Li ,&nbsp;Fan Chen","doi":"10.1016/j.jenvrad.2025.107654","DOIUrl":"10.1016/j.jenvrad.2025.107654","url":null,"abstract":"<div><div>The multi-phase flow in dynamic pore-fracture is crucial to the safety and efficient uranium mining using the in-situ leaching method. In this study, the pore-fracture evolution and multi-phase flow morphology was investigated using the online low-field nuclear magnetic resonance (NMR) system, and the relationship of pore structure, permeability transformation and chemical reaction was analyzed. The results show that the adsorption pore (0.1 ms &lt; AP &lt; 10 ms,46.4%), seepage pore (10 ms &lt; SP &lt; 100 ms,36.6%) and migration pore (100 ms &lt; MP,17.0%) composed the pore-fracture structure, and the chemical corrosion increased the AP, the decreased SP was mainly controlled by the carbonatite precipitation, and MP was enhanced by the dynamic fluid pressure and decreased by the carbonatite precipitation. Compared with the increased permeability of uranium dissolution-dependent pore structure, the carbonatite precipitation-dependent pore structure dominated the decreased permeability during the in-situ leaching. The increased effect on permeability and mineral dissolution for dynamic pressure was gradually weakened by the carbonatite precipitation. Thus, the uranium dissolution was mainly occurred at AP, the uranium-bearing solution migration was controlled by SP, and carbonatite precipitation was occurred at MP. The transformation between the AP, SP and MP was integral dominated by the corrosion dissolution, carbonatite precipitation and fluid kinetics, resulting in the decrease of SP and permeability. The variation in uranium concentration from 0.1 MPa to 0.7 MPa indicates that uranium dissolution and migration in the in-situ leaching process are primarily governed by the interplay of pressure, fluid dynamics, and carbonate precipitation. At lower pressures, enhanced uranium dissolution facilitates greater mobility. However, as pressure increases, carbonate precipitation intensifies, significantly hindering uranium migration and resulting in a marked decrease in uranium concentration. Thus, the conductivity of the uranium-bearing sandstone characterized by the permeability was directly dominated by the SP. The finding provides significant insight into safety and efficiency in-situ leaching uranium mining.</div></div>","PeriodicalId":15667,"journal":{"name":"Journal of environmental radioactivity","volume":"284 ","pages":"Article 107654"},"PeriodicalIF":1.9,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143529351","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessment of radiocesium cycle equilibrium in a deciduous broad-leaved forest using stable cesium: A pilot study after the Fukushima accident","authors":"Wataru Sakashita ,&nbsp;Takuya Manaka ,&nbsp;Ren Tsuneoka ,&nbsp;Tadashi Sakata ,&nbsp;Naohiro Imamura ,&nbsp;Junko Nagakura ,&nbsp;Yoshiki Shinomiya","doi":"10.1016/j.jenvrad.2025.107653","DOIUrl":"10.1016/j.jenvrad.2025.107653","url":null,"abstract":"<div><div>To accurately predict long-term ¹³⁷Cs activity concentrations in stem wood, it is crucial to assess whether the ¹³⁷Cs cycle in forests has reached quasi-equilibrium between trees and forest soil. A method has been proposed to evaluate this equilibrium based on the concentration ratio of ¹³⁷Cs to stable cesium (¹³³Cs) within the tree compartments. However, this assessment has not yet been conducted in the recent situation following the Fukushima accident. In this study, we investigated the relationship between the concentration ratios of ¹³⁷Cs and ¹³³Cs in tree leaves, inner bark, stem wood, and stemflow in a deciduous broad-leaved forest at Kawauchi Village, the Fukushima Prefecture, as of 2022–2023. Our comparisons between ¹³⁷Cs and ¹³³Cs concentrations revealed that ¹³⁷Cs/¹³³Cs concentration ratios were constant in the above-ground compartment and stemflow, suggesting that the cycle of ¹³⁷Cs in the Fukushima forest has reached quasi-equilibrium 11–12 years after the accident. This concentration ratio-based assessment for quasi-equilibrium may be applicable to forest sites where long-term monitoring is not conducted.</div></div>","PeriodicalId":15667,"journal":{"name":"Journal of environmental radioactivity","volume":"284 ","pages":"Article 107653"},"PeriodicalIF":1.9,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143529352","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical simulations of radon diffusion-seepage in single fracture of rock","authors":"Qianran Jia ,&nbsp;Guojie Chen ,&nbsp;Jun Zeng ,&nbsp;Xiongfeng Luo ,&nbsp;Yuanchao Chen ,&nbsp;Junzhe Wang ,&nbsp;Dong Xie","doi":"10.1016/j.jenvrad.2025.107643","DOIUrl":"10.1016/j.jenvrad.2025.107643","url":null,"abstract":"<div><div>The joint roughness coefficient (JRC) of rock fractures significantly effects their seepage characteristics, which is critical in radon diffusion-seepage studies. It is worthwhile to investigate how to accurately characterize the rock fracture roughness and its effect on radon diffusion-seepage patterns within fractured porous media. In this study, the roughness of single-fracture rock is thoroughly considered and described by the Barton curve. Furthermore, this study examines the effects of pressure gradient, temperature, and water saturation on radon diffusion-seepage in fracture-containing porous media. Additionally, this study investigates the variation in seepage velocity within cracks under various pressure gradients, and further analyze the impact of roughness on radon exhalation rate in rocks. The results indicate that: (1) the JRC significantly influences the diffusion-seepage of radon in rocks. The radon exhalation rate on the low-pressure side and the seepage velocity within the fracture increase approximately by 30% and 10%, respectively. (2) The radon exhalation rate on the low-pressure side of the rock correlates positively with the JRC, whereas the radon exhalation rate in the fracture shows a negative correlation with the JRC. Concurrently, the pressure gradient, temperature and water saturation also significantly impact the radon exhalation rate. (3) The seepage velocity within the fracture increases with the rise of osmotic pressure in a fixed JRC value. AS the increase of JRC, the seepage velocity of the rock fracture decreases by approximately 7.9%–10.8%.</div></div>","PeriodicalId":15667,"journal":{"name":"Journal of environmental radioactivity","volume":"284 ","pages":"Article 107643"},"PeriodicalIF":1.9,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143511097","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Conversion of hydrogen gas to water in soil: Implications to fusion contributions","authors":"E.R. Edwards ,&nbsp;B.J. Viner ,&nbsp;M.C. Duff ,&nbsp;S.M. Lyons ,&nbsp;A. Seifert ,&nbsp;H. VerMeulen ,&nbsp;C.E. Aalseth ,&nbsp;B. Boehnke ,&nbsp;J.O. Davis ,&nbsp;B.R. Hackett ,&nbsp;M.C. Huh ,&nbsp;D.B. Hunter ,&nbsp;N.D. Rocco ,&nbsp;J.J. Moran","doi":"10.1016/j.jenvrad.2025.107624","DOIUrl":"10.1016/j.jenvrad.2025.107624","url":null,"abstract":"<div><div>With the continuing development of fusion energy, it is reasonable to be concerned about contamination from the potential release of tritiated water (HTO) plumes, as well as the oxidation of atmospheric tritiated hydrogen gas (HT) releases in nearby soils. We build on past studies by examining oxidation rates of HT to HTO at two sites representing dry and moist soil. We also examine diurnal changes to better constrain rates of microbial HT oxidation and subsequent deposition into soils. We estimate the potential effects of an HTO plume resulting from an oxidation HT. This methodology framework is expected to be useful in the determination of potential health and environmental impacts from HTO as a result of HT releases.</div></div>","PeriodicalId":15667,"journal":{"name":"Journal of environmental radioactivity","volume":"284 ","pages":"Article 107624"},"PeriodicalIF":1.9,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143530997","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A statistical approach to screening isotopic signatures in monitoring for underground nuclear explosions","authors":"Charles R. Carrigan ,&nbsp;Yunwei Sun ,&nbsp;Eric B. Herbold ,&nbsp;Tarabay Antoun","doi":"10.1016/j.jenvrad.2025.107626","DOIUrl":"10.1016/j.jenvrad.2025.107626","url":null,"abstract":"<div><div>The ability to differentiate between atmospheric radionuclide signatures from underground nuclear explosions (UNEs) and signals from other sources, such as medical isotope-production facilities and nuclear reactors, can be critical to the detection and monitoring of unannounced, low-yield nuclear events. Signatures having anomalously high amplitudes, compared to background levels, remain the best indicator in screening for a UNE. However, isotopic composition can further validate a suspected UNE signature, but separation from any atmospheric background composition is first necessary. To date, evaluating the challenges of performing this separation has typically involved comparing an observed background with a highly idealized deterministic model of radioxenon signature production by a UNE that does not consider the influence of post-detonation chemical/physical processes in the detonation cavity or the subsequent gas transport mechanisms that can also affect the isotopic composition of the detected gas signature. In addition, purely deterministic models, as previously employed, overlook the uncertainty inherent in estimating critical parameters characterizing the UNE and its detonation environment. In this paper, we create detailed, multi-parameter models of radionuclide evolution using the widely accepted England and Rider post-detonation radionuclide decay-chain network coupled to detailed models simulating physical production and transport processes affecting the gas signature. Because these models are governed by uncertain parameters including barometric fluctuations, realistic ranges of variation for each of the parameters influencing isotopic composition are then defined. A Latin-Hypercube sampling approach is used to obtain a random distribution of isotopic production and gas transport results associated with a given value of each parameter. We apply these results to background histories of two stations, one providing 4-isotope background measurements and the other providing two-isotope measurements associated with the 2013 DPRK announced UNE.</div></div>","PeriodicalId":15667,"journal":{"name":"Journal of environmental radioactivity","volume":"284 ","pages":"Article 107626"},"PeriodicalIF":1.9,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143479880","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ecosystem effects in the lake affected by the Kyshtym accident","authors":"S.V. Fesenko","doi":"10.1016/j.jenvrad.2025.107641","DOIUrl":"10.1016/j.jenvrad.2025.107641","url":null,"abstract":"<div><div>The ecosystems of two similar lakes, located at different distances from the Mayak chemical plant, were compared to evaluate the potential ecosystem effects of radiation exposure on hydrobionts (phytoplankton, zooplankton, and zoobenthos). Uruskul Lake, the first lake, experienced significant radiation exposure due to the Kyshtym accident in 1957, while the second lake exhibited radiation levels close to background values. The radiation doses received by the aquatic organisms inhabiting Uruskul Lake are presented, and the long-term effects of irradiation on hydrobionts of this lake are discussed.</div></div>","PeriodicalId":15667,"journal":{"name":"Journal of environmental radioactivity","volume":"284 ","pages":"Article 107641"},"PeriodicalIF":1.9,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143464520","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"GATE MARIM DB, a Monte Carlo database for dose assessment of microorganisms exposed to natural α-radioactivity","authors":"Giovanna Rosa Fois,&nbsp;Sofia Kolovi,&nbsp;Vincent Breton,&nbsp;Alexis Pereda,&nbsp;Patrick Chardon,&nbsp;Dariana Llanes Vega,&nbsp;Luca Terray,&nbsp;Lydia Maigne","doi":"10.1016/j.jenvrad.2025.107639","DOIUrl":"10.1016/j.jenvrad.2025.107639","url":null,"abstract":"<div><div>The International Commission on Radiological Protection (ICRP) recommended in 2007 a systematic approach to assess the radiological effects on non-human species. This method transforms radiation exposure into dose rates for living matter, using Dose Conversion Coefficients (DCCs) specific to radionuclides and organisms. Among the long-lived radionuclides, those of the ²³⁸U and ²³²Th decay chains dominate in terms of contributing to natural radiation exposure of non-human species, with significant dose contribution due to their alpha emissions. The ERICA tool was designed to assess dose rates for living organisms weighing from 10^-6 <!-->kg to 10³ <!-->kg. This study extends ERICA’s applicability by using the open-source GATE Monte Carlo platform to compute DCCs for smaller microorganisms exposed to alpha particles (internal or external exposures). This research compares GATE’s results to ERICA’s near its validity limits and explores how DCCs evolve with environmental composition and microorganism size. The open-source GATE MARIM database, including DCC values for 15 alpha-emitting isotopes from the ²³⁸U and ²³²Th decay chains, is now available with a Python Jupyter notebook interface enabling the calculation of dose rates for microorganisms exposed to natural radioactivity.</div></div>","PeriodicalId":15667,"journal":{"name":"Journal of environmental radioactivity","volume":"283 ","pages":"Article 107639"},"PeriodicalIF":1.9,"publicationDate":"2025-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143429504","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Monitoring the changing levels of radon emanation from former uranium mine dumps in different seasons and their effect on the surrounding atmosphere","authors":"Theodor Adam ,&nbsp;Petr Otáhal ,&nbsp;Miroslav Jurda ,&nbsp;Michael Komárek","doi":"10.1016/j.jenvrad.2025.107638","DOIUrl":"10.1016/j.jenvrad.2025.107638","url":null,"abstract":"<div><div>Uranium mining waste represents a considerable potential source of radon emissions in the nearby environment. The project's aim (2021–2024) was to observe and evaluate the effects of seasonal fluctuations in radon release from former uranium mine dumps No.15 and No.4 in the Příbram area and their influence on the surrounding atmosphere. The objective was to describe the radiation situation and homogeneity of the dumps and to record and analyze the impact of climatic conditions, which contribute to radon transport to the adjacent communities. The progressive phase involved aerial and field measurements of the Ambient Dose Equivalent Rate, detecting hot spots using an unmanned aerial vehicle (UAV), collecting air samples with Lukas cells, and continuously monitoring Radon Activity Concentration. Meteorological data filtered for conditions of temperatures, absence of wind, and no precipitation during night-time hours (from 8:00 p.m. to 6:00 a.m.) identified 890 days between 2005 and 2023. This corresponds to an average of 47 days per year during which conditions conducive to radon transport to the vicinity of the dumps were present, which, as determined, influences radon activity concentrations and their subsequent dispersion into the surrounding environment. These measurements confirmed elevated radon activity concentrations in the ambient air, exceeding several kBq/m³ with measured maxima of 27 kBq/m³. This project's integration of monitoring methods has resulted in a novel, comprehensive approach to determining radon transport from the dump to nearby communities. The ability to accurately identify areas with elevated Radon Activity Concentrations (RAC) plays a crucial role in optimizing strategies to mitigate the impact of radon decay products on public health.</div></div>","PeriodicalId":15667,"journal":{"name":"Journal of environmental radioactivity","volume":"283 ","pages":"Article 107638"},"PeriodicalIF":1.9,"publicationDate":"2025-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143419822","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"U(VI) sorption onto rutile surface in the presence or absence of EDTA: A combined macroscopic and spectroscopic study","authors":"Wanqiang Zhou ,&nbsp;Fan Wang","doi":"10.1016/j.jenvrad.2025.107640","DOIUrl":"10.1016/j.jenvrad.2025.107640","url":null,"abstract":"<div><div>Knowledge of the sorption and speciation of uranium at mineral/water interface is essential to predict its long-term behavior. The sorption of uranium on minerals is well known affected by its interaction with EDTA. Here, the sorption of U(VI) on rutile in the presence or absence of EDTA was investigated by combining batch sorption, species calculation, time-resolved fluorescence spectroscopy (TRFS) and X-ray photoelectron spectroscopy (XPS). The batch sorption results suggest that the sorption of U(VI) on rutile is governed by outer-sphere surface complexation under acidic conditions, and undergoes a transformation to inner-sphere surface complexation as the pH increases. In the presence of EDTA, the sorption process is dominated by inner-sphere interactions across the entire pH range. EDTA has been observed to reduce the sorption of U(VI) on minerals, thereby enhancing the mobility of U(VI). Greater inhibition of U(VI) sorption was observed with increasing concentration of EDTA. The TRFS and XPS analysis reveal that the uranium presents as entirely distinct surface complexes on rutile in the presence or absence of EDTA. These findings are essential for understanding the sorption mechanism of U(VI) with EDTA at a molecular scale and developing a reliable assessment for the long-term storage of radioactive waste.</div></div>","PeriodicalId":15667,"journal":{"name":"Journal of environmental radioactivity","volume":"283 ","pages":"Article 107640"},"PeriodicalIF":1.9,"publicationDate":"2025-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143420015","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantifying historical releases of radium-226 from Canadian mining operations to freshwaters","authors":"C.L. Proulx ,&nbsp;B.W. Kilgour ,&nbsp;R.R. Goulet","doi":"10.1016/j.jenvrad.2025.107629","DOIUrl":"10.1016/j.jenvrad.2025.107629","url":null,"abstract":"<div><div>A common misconception is that radium-226 (Ra-226) is released into receiving waters exclusively by uranium mines and mills. In fact, Ra-226 is routinely analyzed in mining effluent across various sectors. Using data reported under the Canadian <em>Metal and Diamond Mining Effluent Regulations</em>, Ra-226 releases from mine effluent were evaluated for the period of 2014–2022. Final treated effluent concentrations ranged from 0.2 to 7800 mBq/L. Data were grouped by mining sector as being either precious metals, base metals, ferrous metal, non-ferrous metals, uranium ore, or diamonds. Mean Ra-226 concentrations were highest for non-ferrous metal mines (51.9 mBq/L), followed by base metal (31.6 mBq/L), diamond (23.8 mBq/L), uranium (22.0 mBq/L), precious metal (15.0 mBq/L), and ferrous metal mines (11.0 mBq/L). Mean concentrations for non-ferrous, base metal, diamond, and uranium mining sectors exceeded the upper tolerance limit (UTL) for natural background concentrations (21.7 mBq/L), calculated using reference data from Northern Saskatchewan. Median concentrations, however, were below the UTL for all sectors, indicating episodic high Ra-226 releases likely influenced by variations in the uranium content of the ore bodies. This study demonstrates that Ra-226 activity concentrations in final treated effluent from uranium mining operations are lower than those from other mining sectors, challenging the perception that uranium operations are the primary source of Ra-226 releases.</div></div>","PeriodicalId":15667,"journal":{"name":"Journal of environmental radioactivity","volume":"283 ","pages":"Article 107629"},"PeriodicalIF":1.9,"publicationDate":"2025-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143394660","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}