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This study attempts a nuclear forensic characterization of uranium in soil samples from a prospective Serule mine in Botswana. The analysis involves the determination of forensic signatures found i...

The aim of the study is to assess the main radiation-hazardous factors that determine the effective dose of personnel during underground uranium mining at the Priargunsky Industrial Mining and Chemical Association, and to summarize the data of the radiation control of the enterprise for 2016-2020. The main factors that create personnel dose loads are: the volume activity of short-lived daughter products of radon decay in the air, the dose rate of external gamma radiation, and the volume activity of long-lived alpha-emitting radionuclides of the uranium-radium series in industrial dust. Information on the structure and values of individual effective doses of workers is presented. Recommendations for improving the radiation monitoring system are given.

The Democratic People’s Republic of Korea (DPRK)’s only confirmed uranium mill is within the Pyongsan uranium mining complex. The ore processing pathway and the production capacity for uranium conc...

To evaluate the radiological risk to human health associated with the ingestion of radionuclides in foods, some different plant foods cultivated in the mining area were collected and analyzed. Results showed that local foods contained higher 210Pb (8.1–150 Bq/kg) and 228Ra (0.3–4.2 Bq/kg) than the worldwide reference values. The annual committed effective doses to children (3.1 mSv/y) and adult (1.3 mSv/y) from the ingestion of local foods might exceed the recommended reference level of 1 mSv/y. Further, the activity concentrations of natural radionuclides in soil and soil-to-plant concentration ratio are also discussed.

This study presents measurements of activity concentrations of natural radionuclides in selected water and soil samples taken from areas affected by the uranium industry in the surroundings of Pribram, Straz pod Ralskem and Mydlovary, Czech Republic. In these areas, the dose equivalent rate was also determined at the sampling locations and additionally also during walkabouts in the surroundings of sludge fields. The activity concentration of water samples was 0.06 ? 0.02 BqL?1 for 226Ra and 0.07 ? 0.07 mgL?1 for 238U while the mean activity concentrations of soil samples were 74 ? 70 Bqkg?1 and 80 ? 77 Bqkg?1 for 226Ra and 238U, respectively. The average value of the dose equivalent rate was of 0.15 ? 0.1 ?Svh?1. These values conform with the nature of the industrial activities which were carried out in the areas and are comparable with measurement results in similar locations worldwide.

Cyclic loading damage in uranium mining is often accompanied by changes in radon exhalation characteristics. Understanding the relationship between rock damage and radon exhalation of uranium ore is therefore important for predicting rock instability and improving monitoring methods to ensure the safety of uranium mines and other underground projects. In this study, we performed constant amplitude cyclic loading and unloading tests on quasi-uranium ore to measure the degree of damage and used the closed chamber method to measure the accumulated radon concentration. The results show a range of damage values between 0.089 and 0.315. The sample with the highest damage value also showed the highest radon exhalation rate of 0.0411 ± 0.00384 Bq m− 2 s− 1. We use the dissipated energy as a damage variable and find a positive correlation between damage and radon exhalation rate. The damage value was fitted with radon exhalation rates, yielding correlation coefficients of 0.97, and shows an inverted S-shaped trend. The results provide a basis for monitoring rock stability using radon exhalation in future uranium mining operations.

The technology of downhole uranium production used at mining enterprises in Kazakhstan is described, the factors affecting the decrease in the filtration characteristics of productive formations are studied in detail, and an effective method is described for increasing the downhole uranium production. The applied methods of intensification of downhole production at uranium mining enterprises are considered, the positive and negative aspects of the electroplasma and chemical methods are discussed. Calculations of the working values of the hydro-wave method of destruction of clogging formations in the well and the parameters of the solution supply during repair and restoration work are presented. Based on the calculation of the operating parameters, a diagram of the dependence of the operating cycle of the hydropercussion machine on the flow rate of the water supplied to the machine is constructed. The developed 3D model of the hydropercussion apparatus for increasing the permeability of the productive horizon is presented. The advantages of the use of the hydrodynamic method for restoring the permeability of the productive horizon in the conditions of downhole uranium production in difficult mining and geological conditions are disclosed. The optimal parameters for intensification of downhole uranium production in difficult mining and geological conditions are recommended, and a method for using a hydropercussion apparatus in combination with traditional methods of well regeneration is developed.

In present study, distribution of 210Po and 210Pb in ground water in uranium mineralized zone of Jaduguda in East Singhbhum region of Jharkhand state, India is evaluated. Activity concentration of 210Po ranges from

The research was performed under the grant financing project of the Ministry of Education and Science of the Republic of Kazakhstan (GF) AP08856422 “Development of an innovative technology for intensifying downhole uranium mining using a hydrodynamic decolmatization device in combination with a complex of multifunctional chemicals”.

The authors of the paper are grateful to A.I. Matunov, Deputy General Director for Geology and Subsoil Use of JV Budyonovskoye LLP, for rendering a valuable advice and assistance in collecting statistical data.

For the first time, exposure to uranium (U) among the residents living around U-mining sites in Siavonga, Zambia, was assessed by determining the concentrations of U in their urine using the Inductively Coupled Plasma-Mass Spectrometry. We further investigated the correlations for urinary U concentrations from the current study with the U concentrations in drinking water and cow milk from our previous studies conducted in the same study sites. The urinary U concentration for the residents from communities situated ≤4km from the U-mining sites, i.e. U-mining area, had a median concentration of 60.67 µg/L. Comparably, residents from communities located about ≥67km from the U-mining sites, i.e. non-mining area, had urinary U concentrations with a median of 0.72 µg/L. Positive correlations with urinary U concentration were recorded for U concentrations in drinking water (rs= 0.64, p

This paper summarizes the history of what is known about uranium mining in the DPRK; describes the major uncertainties regarding DPRK uranium production; notes some of the key techniques, as used in preparing estimates of nuclear sector activity in other nations, that might be available to assist in narrowing the range of estimates of DPRK uranium and processed fissile material production; summarizes estimates of enriched uranium and plutonium production prepared by other authors; describes existing estimates of the amounts of fissile materials used in nuclear weapons tests and exported; provides a demonstration of the potential impact of remote sensing methods and testing in the DPRK in reducing uncertainties in cumulative historical uranium production, and thus in fissile materials inventories; and, offers conclusions, resulting from the potential impacts of uncertainty reduction approaches, as to which verification procedures should be key targets during negotiations with the DPRK.

Biological uranium (VI) reduction was investigated using a mixed-culture of U(VI) reducing bacteria isolated from tailing dumps at an abandoned uranium mine in Pharaborwa (Limpopo Province, South Africa). A fixed-film reactor was used in the investigation, whereby the reactor was operated in the up-flow mode under fully submerged conditions at a recirculation ratio of, Qin/QR = 20. The performance of the bioreactor was evaluated over a range of influent U(VI) concentrations [75–100 mg U(VI)/L] and 24 h hydraulic retention time [HRT]. Complete U(VI) removal was observed in phases with 30–85 mg/L influent U(VI). When influent U(VI) was increased to 100 mg/L, approximately 60% U(VI) removal was achieved. The oxidation states of reduced uranium species were determined by Scanning and Transmission Electron Microscopy followed by X-ray Diffractometer (SEM/TEM-XRD). Earlier studies in batch systems showed that U(VI) was non-toxic to U(VI) reducing organisms at concentrations up to 400 mg/L. The decrease in U(VI) removal efficiency observed in the fixed-film reactor after 42 days was therefore attributed to the accumulation of U(IV) hydroxide precipitates in the reactor. Genetic identification using the 16S rRNA gene sequence analysis showed that the species Kocuria turfanensis, Arthrobacter creatinolyticus, Bacillus licheniformis, and Microbacterium aerolatum survived from the original cultures. The feasibility of continuous removal of U(VI) in an inoculated indigenous culture system was thus demonstrated.

Level of the heavy metals was measured in tissue and blood samples from 19 cattle, 20 horse, 38 camel, 89 sheep and 102 goats in several mining areas such as Ulaanbadrakh soum (uranium mining) and Airag soum (spar mining) of Dornogovi province. In addition, level of the lead in the liver of sheep and goat samples from Zuunbayan soum of Dornogovi province was bit higher than same samples from other sampling areas. In the result, level of the copper was 814 ppm in the liver samples of sheep, 734 ppm in the liver samples of goat and they were and 2.5-4.0 fold higher than international permissible value. On the other hand, level of the cadmium was 352,789±122,64 mg/kg in kidney samples of horse, indicating that amount of these heavy metals were enough high to have toxicities in animals. Except for these results, level of heavy metals was not higher than international permissible value in plant and soil samples. Говийн бүсийн уул уурхайн хайгуул олборлолтын бүс орчимд бэлчээрлэж буй малын эд, эрхтэн дэх хүнд металлын агууламжийг тодорхойлсон судалгааны дүнгээс Хураангуй: Дорноговь аймгийн Улаанбадрах, Зүүнбаян сумын нутаг дэвсгэрт ураны хайгуул, туршилтын олборлолт явуулж буй бүс нутаг, Айраг сумын жоншны уурхайн олборлолтын бүс нутаг орчим бэлчээрлэж буй 89 хонь, 102 ямаа, 19 үхэр, 38 тэмээ, 20 адууны эд эрхтэн болон цусанд хүнд металлын (хар тугалга, зэс, кадми) агууламжийг тодорхойлов. Хар тугалга нь тархи болон бөөрийг маш хүндээр гэмтээдэг, ясыг зөөлрүүлдэг, төдийгүй хордолт нь үхэлд хүргэх аюултай бодис билээ. Маш удаан хугацаагаар энэ бодист өртөгдсөн хүүхэд төдийгүй томчуудын мэдрэлийн системийг гэмтээдэг, бага багаар хуримтлагдсаар хордлого үүсгэх, хүний мэдрэлийн эрхтэнд муугаар нөлөөлөх талтай. Хар тугалга нь хүний биед нөлөөлөх байдлаараа хортой бодисын ангилалд ордоггүй. Хөнөөлт бодист тооцогдоно. Иймд мал амьтны эд эрхтэнд агуулагдаж буй хар тугалга болон зэсийн агууламжийг дахин нарийнсудлах шаардлагатай байна. Түлхүүр үг: Хар тугалга, зэс, Индукцэн холбоост плазм масс спектрометр.

Activities associated with mining of uranium have generated significant quantities of waste materials containing uranium and other toxic metals. A qualitative and quantitative study was performed to assess the situation of nuclear pollution resulting from waste of drilling and exploration left on the surface layer of soil surrounding the abandoned uranium mine hole located in the southern of Najaf province in Iraq state. To measure the specific activity, twenty five surface soil samples were collected, prepared and analyzed by using gamma- ray spectrometer based on high counting efficiency NaI(Tl) scintillation detector. The results showed that the specific activities in Bq/kg are 37.31 to 1112.47 with mean of 268.16, 0.28 to 18.57 with mean of 6.68 and 132.25 to 678.33 with mean of 277.49 for 238U, 232Th and 40K respectively. Based on these values, radium equivalent activity in Bq/kg and absorbed dose rate one meter above the ground surface nGy/h were calculated and found to be vary 52.72 to 1189.84 and from 25.02 to 553.01. The indoor and outdoor annual effective dose rate in mSv/y ranged from 0.12 to 2.71 and from 0.03 to 0.67 respectively. To evaluate the dangerous of the study area, the external (Hex) and internal (Hin) hazard indexes are calculated and found to be ranged 0.14 to 3.21 and from 0.24 to 6.22. For the purpose of assessing the seriousness of the study area, results were compared with the world wide average. This comparison indicated that the study area is not safe from the radiological protection point view.

Background Contamination of cow milk with uranium (U) is attracting global attention owing to U’s radio-toxicity and chemical toxicity in humans and animals. Concentrations of U in 223 cow milk samples from indigenous breeds reared in the proximity of a U mine in Zambia were measured using the inductively coupled mass spectrometry, and the human health risks from exposure to U through milk consumption were assessed. Results Milk from cattle reared in the U-mining area showed a significantly higher U-mean concentration (0.83 ± 0.64 µg/L; t = 9.95; tα = 0.05, p > 0.05) than milk from cattle reared in the non-mining area (0.08 µg/L ± 0.05). Among the residents of the U-mining area, the mean estimated daily intake (EDI), the target hazard quotients (THQs) and the target carcinogenic risks (TCRs) were all significantly (p Conclusions Since the EDIs, THQs and TCRs and the U level in the cow milk were all within the World Health Organization’s and the United States Environmental Protection Agency’s permissible limits of 0.6 µg/kg-bw/day, –4 and 30 µg/L, respectively. The current study, therefore, has insufficient evidence to implicate U exposure through consumption of cow milk in any non-carcinogenic or carcinogenic human health complications that are currently prevailing in the study area. Graphic abstract

Elevated levels of radon and thoron in the indoor atmosphere may cause the deleterious effects on the mankind. Mining sites and their environs attract a special interest in radon studies as higher levels are frequently reported in the habitats. In the present study, radon and thoron levels were measured in the dwellings of Buddonithanda, a village in the environs of proposed uranium mining site, with pin-hole (SSNTDs) dosimeters for the period of a year. The measured radon and thoron levels were found to vary widely from 14 to 675 Bq m−3 (geometric mean = 94 Bq m−3) and from 21 to 704 Bq m−3 (geometric mean = 121 Bq m−3), respectively. An attempt was made to understand the large spatial variation of these levels. The seasonal and diurnal variation studies were used in unraveling the behavior of the radioactive isotopes in indoor environment and the same was explained with the help of a simplified mathematical model. Quantification of inhalation dose due to radon and thoron was done with suitable occupancy factors.

Made available in DSpace on 2021-06-25T11:18:23Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-01-01 Mine restoration is a long and ongoing process, requiring careful management, which must be informed by site-specific, geochemical risk assessment. Paired topsoil and tree core samples from 4 sites within the uranium mining complex of INB Caldas in Minas Gerais (Brazil) were collected. Soil samples were analysed for their total content of Co, Fe, Pb, U and Zn by XRF, and subsequently, the potential environmental bioavailability of these metals were investigated by DGT and pore water analysis. In addition, results were compared with metal concentrations obtained by Tree Coring from the forest vegetation. In all sampling areas, mean total concentrations of U (Ctot. = 100.5 ± 66.5 to 129.6 ± 57.1 mg kg−1), Pb (Ctot. = 30.8 ± 12.7 to 90.8 ± 90.8 mg kg−1), Zn (Ctot. = 91.5 ± 24.7 to 99.6 ± 10.3 mg kg−1) and Co (Ctot. = 73.8 ± 25.5 to 119.7 ± 26.4 mg kg−1) in soils exceeded respective quality reference values. Study results suggest that AMD caused the increase of labile concentrations of Zn in affected soils. The high lability of the elements Pb (R = 62 ± 34 to 81 ± 29%), U (R = 57 ± 20 to 77 ± 28%) and Zn (R = 21 ± 25 to 34 ± 31%) in soils together with high bioconcentration factors found in wood samples for Pb (BCF = 0.0004 ± 0.0003 to 0.0026 ± 0.0033) and Zn (BCF = 0.012 ± 0.013 to 0.025 ± 0.021) indicated a high toxic potential of these elements to the biota in the soils of the study site. The combination of pore water and DGT analysis with Tree Coring showed to be a useful approach to specify the risk of metal polluted soils. However, the comparison of the results from DGT and Tree Coring could not predict the uptake of metals into the xylems of the sampled tree individuals. Environmental Studies Center (CEA) São Paulo State University (UNESP), Avenida 24-A, 1515 Institute for Global Security School of Biological Sciences Queen’s University Belfast, BT9 5DL Indústrias Nucleares do Brasil S.A. - INB Rodovia Poços de Caldas - Andradas, km 20,6 (BR 146, km 540) Department of Geology and Basin Studies Laboratory (LEBAC) São Paulo State University (UNESP), Avenida 24-A, 1515 Environmental Studies Center (CEA) São Paulo State University (UNESP), Avenida 24-A, 1515 Department of Geology and Basin Studies Laboratory (LEBAC) São Paulo State University (UNESP), Avenida 24-A, 1515

Science and technology developed by the Manhattan Project during the second world war created an entirely new industry based on the use of uranium (U) as a source of power and for nuclear weapons. This resulted in near instantaneous development of a large market for U, and U.S. production went from nearly nonexistent in 1949 to 35 Mlbs/year of U concentrate, represented as U3O8, by 1959. This production continued for 25 years and then experienced a sharp decline due to declining markets as a result of decreased interest in nuclear power and less expensive sources of foreign U. Most U.S. production was done by open pit and underground mines from sandstone deposits located in the western states of Arizona, Colorado, New Mexico, and Utah. The only current U mining in the U.S. uses the in situ recovery process (ISR, also referred to as in situ leach or ISL) at a few mines in Wyoming and Nebraska. Large ISR mines located in south Texas are no longer active. The rapid development of the U industry in the west and its almost equally rapid demise in the U.S. mean that most of the impacts on human health and the environment are due to legacy operations that began before protective laws and regulations were passed in the 1970s and 1980s.

The article describes the current situation in the global uranium concentrate market, explains the reasons for the formation of an excess amount of finished goods and the subsequent decreasein prices. The authorsevaluated the prospects of using market mechanisms to improve the financial results of Russian uranium mining enterprises. The location of the main mining centers in comparison with the centers of consumption of finished goods, pricing for the products of uranium mining companies, the dynamics of price changes over the past 20 years, the influence of non-market factors on the supply of finished products are analyzed.This study led to the conclusion that the expectation of changes in the market situation is not viable in a long term. The authors outlined the direction to improve the profitability of mining enterprises by introducing technological changes aimed at reducing the cost of the final product.

Radium is the most common source of alpha radiation exposure to humans and non-human species in the environment but the dosimetry is complicated by the decay chain which involves gamma exposure due to radon daughters. This paper seeks to determine the separate contributions of alpha and gamma doses to the total dose and total direct and non-targeted effect in a fish and a human cell line.This study aimed to isolate the effect of alpha particles following exposure to low doses of radium in cells, and their progeny which received no further exposure. This was initially done by comparing the survival values of a human keratinocyte cell line (HaCaT) and an embryonic Chinook salmon cell line (CHSE-214) exposed to gamma radiation, from survival of the same cell lines exposed to mixed alpha and gamma radiation through exposure to Ra-226 and its decay products. A Monte Carlo simulation was later performed to determine the contributions of radium decay products including radon daughters.The human cell line showed increased radioresistance when exposed to low doses of alpha particles. In contrast the fish cell line, which demonstrated radioresistance to low dose gamma radiation, showed increased lethality when exposed to low doses of alpha particles. Significant and complex levels of non-targeted effects were induced in progeny of irradiated cells. The simulation showed that gamma and beta decay products did not contribute significant dose and the highest beta dose was below the threshold for inducing non-targeted effects.The results confirm the need to consider the dose-response relationship when developing radiation weighting factors for low dose exposures, as well as the need to be aware of possible cell line and species differences.

Resumo: O artigo discute os processos de publicização dos problemas do nuclear em Caetité, Bahia. Desde o início da operação da mina de urânio na região, no ano de 1999, uma série de atores locais e não locais têm produzido evidências dos problemas decorrentes da extração do mineral para combustível das usinas nucleares brasileiras. Neste artigo argumenta-se que esse processo, ao mesmo tempo que constitui o nuclear e o urânio como uma situação problemática, também transforma os atores a ela concernidos, construindo os processos através dos quais questões do nuclear se tornam visíveis. Para isso, baseia-se em documentos, relatórios técnicos, materiais publicados em jornais e observação de campo de parte dos atores envolvidos nas questões do nuclear. Concluímos que as exigências dos atores passam a ser construídas a partir de evidências que seguem constrangimentos metodológicos próximos daqueles produzidos pela operação da mina, baseado em monitoramento e avaliação de dados técnicos. Mas, diferente da manutenção do nuclear como uma caixa preta, os atores publicizam o urânio e o nuclear como um problema público. Abstract: The article presents the processes of publicization nuclear problems in Caetité, Bahia. Since the beginning of the operation of the uranium mining in the region in 1999, local and non-local actors have produced evidence of problems arising from the extraction of the uranium from Brazilian nuclear power plants. We discuss that this process, while constituting nuclear and uranium as a problematic situation, also transforms the actors concerned, building processes through which nuclear issues become visible. We analyze documents, technical reports, newspapers and field observation on the part of the actors involved in nuclear issues. We conclude that the demands of the actors are dependent on evidences that came out through methodological constraints similar to those produced by the mine operating company, based on monitoring and evaluation of technical data. But unlike maintaining nuclear as a black box, local and non-local actors have exposed uranium and nuclear energy as a public problem. Resumen: El artículo discute los procesos de divulgación de los problemas del ámbito nuclear en Caetité, Bahía. Desde el inicio de la operación de la mina de uranio en la región, en el año de 1999, una serie de actores locales y no locales han generado evidencias de los problemas resultantes de la extracción del mineral usado como combustible en las plantas nucleares brasileñas. En este artículo se argumenta que este proceso, al mismo tiempo que constituye la propia cuestión nuclear -junto con el uranio- como una situación problemática, también transforma a los actores concernientes a ella, construyendo procesos a través de los cuales las cuestiones del ámbito nuclear se tornan visibles. Para esto, este artículo se basa en documentos, informes técnicos, material publicado en periódicos y observaciones de campo por parte de los actores involucrados en el ámbito nuclear. Concluimos que las exigencias de los actores son construidas a partir de las evidencias que siguen restricciones metodológicas cercanas a aquellas producidas por la operación de la mina, basados en el monitoreo y la evaluación de datos técnicos. No obstante, al contrario de mantener al tema nuclear en secreto, los actores divulgan al uranio y a la propia cuestión nuclear como un problema público.

The town of Zhovti Vody is a ‘capital’ of uranium mining and processing industry of Ukraine. The mining and processing of uranium has been carried out in this area for more than 60 y. During this period, due to increasing production activities, the town has grown significantly. As a result of production activities and also due to the human factor, the territory of the town was contaminated by radioactive rocks. In addition, out of ignorance, radioactive rocks were used in the construction of houses and roads. To normalize the radiation situation in the town, a targeted State Programme was adopted in 2003 for a period of 10 y. In 2013, the Programme was subsequently extended until 2022. In accordance with this Programme, decontamination of the urban territory, measurements of radon isotopes in houses and anti-radon reconstructions of the premises have been performed. The results of these works are described in this article.

International audience; In highly permeable sedimentary rock formations, U extraction by in-situ leaching techniques (ISR À In-Situ Recovery) is generally considered to have a limited environmental impact at ground level. Significantly, this method of extraction produces neither mill tailings nor waste rocks. Underground, however, the outcome for 238 U daughter elements in aquifers is not well known because of their trace concentrations in the host rocks. Thus, understanding the in-situ mobility of these elements remains a challenge. Two samples collected before and after six months of ISR experiments (Dulaan Uul, Mongolia) were studied with the help of a digital autoradi-ography technique (DA) of alpha particles, bulk alpha spectrometry, and complementary petrographic observation methods. These techniques demonstrate that before and after leaching, the radioactivity is concentrated in altered and microporous Fe-Ti oxides. Most of the daughter elements of U remain trapped in the rock after the leaching process. DA confirms that the alpha activity of the Fe-Ti oxides remains high after uranium leaching, and the initial secular equilibrium of the 238 U series for 230 Th to 210 Po daughter elements (including 226 Ra) of the fresh rocks is maintained after leaching. While these findings should be confirmed by more systematic studies, they already identify potential mechanisms explaining why the U-daughter concentrations in leaching water are low.

Environmental contamination caused by uranium mining is becoming a worldwide issue due to its negative impact on the environment. The aim of this study is to evaluate the contamination levels of riparian forest stands and their interaction with pollutants on the example of two localities with long and short-term uranium mining closure. Notably high Cu content, which exceeded the lower range of the toxicity limit in 50&ndash, 75% of the cases, was detected in the leaves. Increased U content also represents a potential risk. As both of the elements have a negative effect particularly on the root system, it can be assumed that the soil-stabilizing and water erosion-reducing functions of the stands may be reduced. Extremely high U content (51.8 mg/kg DA) in the leaves of Aesculus hippocastanum L. indicates its potential for phytoremediation. Significantly higher U content determined at the locality with the long-term closure of mining was probably caused by the instauration of the shallow hydrogeological circulation after mine inundation. Strong correlation between U and Pb suggests identical trend of their uptake and accumulation by plants. A significant dependence of the level of contamination on the distance from its source was not demonstrated. Therefore, the management of mining areas should focus on the protection of riparian forest, which can through its stabilizing and erosion-reducing functions and through suitable species composition effectively prevent spreading of contamination.

Starting in 1946, companies such as Kerr McGee, Vanadium Corporation of America, Foote Mineral, Amex and Climax began a twenty year commitment to produce bomb-grade uranium from the federal government and fuel-grade material for civilian nuclear plants. The Navajo nation of New Mexico and Arizona have perhaps suffered the most egregious harm due to uranium mining and milling in the American Southwest. Uranium mining and milling operations have regularly desecrated or destroyed places that are sacred to different Southwest nations. The Grants Uranium Belt of northwestern Mew Mexico is home to thousand-year old Pueblo communities. The eventual contamination the Grants Belt people faced when the Anaconda mine stopped operating was mind boggling: they had hosted the largest uranium strip mine on the planet for nearly thirty years. The deserts, forests and mountains of this land are thousand year carvings by water, wind and sun.

Gamma logging for uranium exploration is currently based on total counting with the Geiger–Muller gas detectors or NaI(Tl) scintillators. However, the total count rate interpretation in terms of uranium concentration may be impaired in case of roll fronts when the radioactive equilibrium of the natural 238U radioactive chain is modified by the differential leaching of uranium and its daughter radioisotopes radium, radon, and so on. Indeed, in the case of secular equilibrium, more than 95% of gamma rays emitted by uranium ores come from 214Pb and 214Bi isotopes that are in the back end of the 238U decay chain. These two isotopes might produce an intense gamma signal even when uranium is not present, or with a much smaller activity, in the ore. Therefore, gamma spectroscopy measurements of core samples are performed on the surface with HPGe detectors to directly characterize uranium activity from the 1001-keV gamma ray of 234mPa that is at the beginning of the 238U chain. However, due to the low intensity of this gamma ray, acquisitions of several hours are needed. In view to characterize uranium concentration within a few minutes, we propose a method using both the 92 keV gamma rays of 234Th and 235U and the 98.4-keV uranium X-ray. This last is due to uranium self-induced fluorescence caused by gamma rays of the uranium chain, mainly 214Pb and 214 Bi. The gamma rays of 214Pb and 214Bi undergo scatterings in the sample leading to photons with energy in the 100-keV range that favor photoelectric interactions and, thus, fluorescence. The comparison of the uranium activity obtained with the 92- and 98.4-keV lines allows detecting a uranium heterogeneity in the ore. Indeed, in the case of uranium nugget, the 92-keV peak leads to underestimated uranium concentration due to the gamma self-absorption, but on the contrary, the 98.4-keV peak leads to an overestimation because of increased fluorescence. In order to test this new approach, tens of uranium ore samples have been measured with a handheld HPGe FALCON 5000 detector.

There is a description of technology by borehole uranium mining in Kazakhstan. The factors which affect for reduction of filtration characteristics in productive reservoirs are studied in detail and described an effective method for increasing borehole uranium production. The processes that occur during borehole mining of uranium with the use of sulfuric acid as solvent, as well as the conditions and reasons for reducing the productivity of geotechnical wells during their operation are considered. The results of experimental work on the intensification of borehole uranium mining in complex mining and geological conditions are analyzed and discussed, comparative graphs of the content of uranium in the productive solution, the flow rate of wells, the degree of extraction and the volume of production before and after the experiments are constructed. The results of experimental work on the efficiency of borehole uranium production, the content of uranium in PS and the productivity of wells, with predominance of the chemical type of sedimentation, are positively evaluated. The optimal parameters for the intensification of borehole uranium production in complex mining and geological conditions are recommended, and method for using complex of multi-purpose chemical reagents in combination with traditional methods of well regeneration is developed.

There is a long history of uranium mining and milling in what is now the Czech Republic, with the main exploitation beginning in the second half of the 19th century. The greatest expansion was during the Cold War, which was then reduced after political changes in eastern Europe in the 1990s. Thereafter, almost all uranium work was stopped, the mines and mills were closed, and plans for decommissioning and remediation of sites and facilities were initiated. The paper describes the application of the regulatory framework for the decommissioning and remediation of the uranium waste sites and facilities in the Czech Republic, illustrated by examples of deep and surface mining, in-situ leaching sites, and ore processing facilities. It builds on information provided as a case study for the Nuclear Energy Agency’s Expert Group on Legacy Management. Some practical experience and lessons learned are presented. The sharing of the lessons and experience is noted as an important mechanism for avoiding the creation of future legacies.

Aquatic environments downstream of uranium operations (mining/milling) in Northern Saskatchewan are exposed to a variety of chemical and physical disturbances. There is extensive regulatory documen...

High pressure, radon bearing water has been identified as one of the most critical challenges in mining the high-grade uranium deposit at the McArthur River Operation, Cameco Corporation. The ore deposits are located between 490 and 640 m below the surface and surrounded by water bearing Athabasca sandstone, a graphitic P2 fault zone, and highly altered ground. This paper introduces the inflow risk management program at McArthur River Operation, which includes various hydrogeological challenges and the corresponding strategies applied, such as risk-based probe and grout programs (geological, hydrogeological, and geotechnical), ground freezing programs, and comprehensive ground control programs. These programs have been developed, tested, and proven successful over years of mining practices. Working with this world class deposit of high risk and low tolerance, it is believed that these experiences might be beneficial to other mining operations with similar hydrogeological characteristics. Keywords: Inflow risk management, Geotechnical and development probe and grout programs, Dewatering infrastructure, Ground freezing, Ground control

We studied the influence of terrain, geology and weather condition on radon concentration in the atmosphere and occurrence of radon density currents. The survey was carried out in Kowary (SW Poland) and in the spoil tip formed during uranium mining. The measurements of radon concentration were performed using SSNTD LR-115. The measurements of uranium thorium and potassium content in soil were carried out using gamma ray spectrometer Exploranium RS-230. We noticed that terrain and stability of weather condition had significant impact on atmospheric radon concentration. The seasonal variations of radon concentrations in Kowary differ from those usually registered in temperate climate. Based on our analyses, the increase of radon concentration in winter and spring was caused by inversion occurring in that area during these seasons. The observed seasonal variations of radon concentrations in the spoil tip were consistent with those characteristic for temperate climate (the highest radon concentration registered in spring and summer and the lowest in winter and autumn). The spoil tip is located above 900 m a.s.l. and is not cover by grass or trees. These circumstances promoted radon exhalation. The air movement above the spoil tip area is intensive, even in winter time. The average atmospheric radon concentration in the spoil tip was 318 Bq m− 3. The performed research did not reveal occurrence of radon density currents and flow of radon from the spoil tip to lower lying areas in Kowary. We noticed interdependence of atmospheric radon concentration measured at the height of 1.5 above the ground and uranium content in soil and no correlation between thorium content and radon concentration. The lung cancer in residents of Kowary which is more common than in Poland can be associated with increased concentrations of radon. The average radon concentration in the atmosphere in Kowary was 79 Bq m− 3.

This review examines the history of uranium mining in sub-Saharan Africa to contextualize recent extraction developments on the continent. From the secretive days of uranium mining in the first half of the twentieth century to today's ambitions of African nations to domestically mine uranium and generate nuclear power, Africa remains largely invisible from the global nuclear record in spite of its historical significance. The Cold War dynamics that bound the nuclear world are increasingly untenable as African states turn to nuclear power to meet growing energy deficits. This article reveals how African states challenge narratives serving to obscure the African origins of uranium. Connecting the history of uranium mining with non-proliferation agreements and aspirations for nuclear power, this review examines the current place of Africa in the nuclear world, and looks to the future.

The paper shows, that radionuclides from the stony rocks of uranium mines can be leached by atmospheric precipitations. In acid conditions, a degree of leaching is greater. Goal. The aim of this investigation was to study the distribution of radionuclides in uranium minings and their impact on the environmental contamination. Materials and methods. The study was carried out in two stages. In the first stage, a blade of rock was mixed with distilled water in proportions of 0,3 kg of gravel and 1 liter of water. After thirty days of soaking, water was sent to the gamma-spectrometric analysis to Canberra’s spectrometer (USA) with a high-purity germanium detector. In the second stage, we carried out the similar experiment with water, wich was acidified to pH = 3. Contamination levels of areas near the in-situ leaching mine were determined. Intervention levels were used to estimate risk and possible water consumption by the population. Estimations were carried out taking into account the combined presence of several radionuclides in the water. Results. The results of these studies have shown that the distribution of radionuclides from the source of the contamination is about 360 meters during the 30 y period. The stream, along which samples of soil were collected and studied, was formed by the miner waters that flow along small ruts towards a village, thereby increasing the likelihood of water use by the public. Conclusions. The uranium mines are the source of radioactive contamination. Radionuclides are distributed due to the erosion of rocks and leached out of the stony rock by precipitations. The extent of leaching is significantly increased in an acidic environment, which takes place near the in-situ leaching mines.

Uranium ore has been mine for decades before it was abandoned in Mika village of Yorro LGA of Taraba state. Uranium mining poses high risk of radiation exposure to members of the public and local community. Despite the high risk associated with uranium ore deposit and mining in the area, the local community have continued to live in the surroundings of the abandoned mine sites and engaging in their day to day socio-economic activities. No attempt has been made to investigate the characteristics and current condition of the abandoned uranium mine site in the area and its potential impacts on the socio-economic life of the people. This study examined the potential environmental impact that could arise from the abandoned uranium mine site and associated past activities. Data was generated through desk review of existing data sources, including literatures, field observation and measurements of abandoned uranium mine pits and related features. Measuring tape and Garmin 12 X GPS (Global Positioning System) was used in the measurements. Interview of key informants was also carried out. Findings from the study show that the uranium ore is found on hill top (425metre above sea level). The mine wastes and overburden were deposited around the mine pits. Most of the overburden materials have been washed away. Findings from the study revealed that scooping of uranium ore samples have been ongoing in Mika area before independence in 1960. The uranium mineral samples collected from the site were taking to France and subsequently to Iran. Despite the risk posed by the abandoned uranium mine pit, the local communities insist that they did not observe any strange sickness or effects associated with the mining activities. Many of them depend on the water collected in the abandoned uranium mine pit for domestic consumption. Based on the findings, the study recommends periodic monitoring of water and agricultural crop to ascertain the possible effects of radioactivity associated with the uranium ore deposits in the area and enlightenment of the local communities on the potential impact of the abandoned uranium mines on their land, soil, air and water in the area.

The following explanations relate to processing residues and their storage in various locations (tailings ponds) as a result of SDAG Wismut’s uranium mining operations in Saxony and Thuringia. These are possibly the largest uranium mill tailings ponds in the world, so that they can be described as reference objects. Comparisons are made with remediation programs and legal requirements in the USA, so that the reader can make comparisons with corresponding site specific projects and thus one may also acquire ideas for options for site specific solutions.

The diffusion length of 222Rn in uraniferous waste rock was determined through a novel experiment. Large PVC columns were filled to different depths in the range from 0.5 m to 3.0 m with waste rock material from the Ranger uranium mine and the build-up of 222Rn activity concentration in the column headspace above the material was measured after closing the columns with a lid. Measurements were made approximately one month after filling the columns and again after approximately one and two years. The average 222Rn diffusion length derived from the measurements was 1.9 ± 0.2 m in the dry material. The corresponding diffusion coefficient was (7.3 ± 0.7) × 10−6 m2 s−1. For an infinitely thick layer of the dry material, the average value of the 222Rn exhalation flux density relative to the 226Ra activity concentration was estimated as (5.3 ± 0.3) × 10−4 Bq m−2 s−1 per Bq kg−1. From the diffusion length, the waste rock material was characterised as both a source and attenuator of 222Rn for its proposed use as the surface cover on the final landform of the remediated Ranger uranium mine.

Public exposure to external gamma radiation on the waste-rock-covered-8.5-km2-planned final landform from rehabilitation of the Ranger uranium mine was assessed. The average above-background dose rate from external gamma radiation on the planned final landform was determined to be 6.0 × 10−3 mSv d−1. This dose rate was one order of magnitude higher than that for inhalation of radon progeny and two orders of magnitude higher than that for inhalation of radionuclides in dust on the final landform. The above-background annual effective dose to the public from external gamma radiation when the envisioned land use by Aboriginal traditional owners was averaged over the entire 79 km2 Ranger Project Area was about 4.1 × 10−2 mSv. The results of this study may provide general guidance to sites elsewhere on the relative importance of the external gamma pathway and assist in the development or assessment of rehabilitation plans for uranium mining sites.

Studies are being conducted for the past few decades in and around the uranium mining sites across the globe to identify environmental nuclear radiation risk to the common public. The area near Dasarlapally village was identified for uranium exploration by the AMDER, Hyderabad. The present study was carried out to measure the indoor radon and thoron activity concentrations in the dwellings of Dasarlapally village. For this purpose different types of dwellings were chosen randomly across the village. The measured annual average concentration of radon and thoron in dwellings were found to be 141 ± 42 and 139 ± 77 Bqm−3, respectively, and the calculated annual effective inhalation dose due to radon was determined to be 3.5 mSv. Seasonal variation and diurnal variation of radon and thoron activity concentration were investigated. The variation of radon and thoron activity concentration in different types of dwellings was also studied, and the variation was found to be statistically insignificant. The uncertainty propagated in the effective inhalation dose due to thoron was discussed.

It is well established that high radon exposures increase the risk of lung cancer mortality. The effects of low occupational exposures and the factors that confound and modify this risk are not clear and are needed to inform current radiation protection of miners. The risk of lung cancer mortality at low radon exposures (

Gamma logging for uranium exploration are currently based on total counting with Geiger Müller gas detectors or NaI (TI) scintillators. However, the total count rate interpretation in terms of uranium concentration may be impaired in case of roll fronts, when the radioactive equilibrium of the natural 238U radioactive chain is modified by differential leaching of uranium and its daughter radioisotopes of thorium, radium, radon, etc. Indeed, in case of secular equilibrium, more than 95 % of gamma rays emitted by uranium ores come from 214Pb and 214Bi isotopes, which are in the back-end of 238U chain. Consequently, these last might produce an intense gamma signal even when uranium is not present, or with a much smaller activity, in the ore. Therefore, gamma spectroscopy measurements of core samples are performed in surface with high-resolution hyper-pure germanium HPGe detectors to directly characterize uranium activity from the 1001 keV gamma ray of 234mPa, which is in the beginning of 238U chain. However, due to the low intensity of this gamma ray, i.e. 0.84 %, acquisitions of several hours are needed. In view to characterize uranium concentration within a few minutes, we propose here a method using both the 92 keV gamma ray of 234Th and the 98.4 keV uranium X-ray. This last is due to uranium self-induced fluorescence caused by gamma radiations of 214Pb and 214Bi, which create a significant Compton scattering continuum acting as a fluorescence source and resulting in the emission of uranium fluorescence X-rays. The comparison of the uranium activity obtained with the 92 keV and 98.4 keV lines allows detecting a uranium heterogeneity in the ore. Indeed, in case of uranium nugget, the 92 keV line leads to underestimated uranium concentration due to gamma self-absorption, but on the contrary the 98.4 keV line leads to an overestimation because of increased fluorescence. In order to test this new approach, several tens of uranium ore samples have been measured with a handheld HPGe FALCON 5000 detector.