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Numbers of radioactive tailings were produced in the process of uranium mining and milling.In this study,radiation environment monitoring was carried out on a decommissioned uranium mining and mill...

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...

Purpose. Improving the efficiency of borehole uranium mining and the selection of special decolmating solutions to improve the filtration characteristics of the seam due to effective destruction, as well as by preventing the sedimentation in the productive horizon, depending on the mineralogical composition and structure of sediment-forming materials. Methods. The advantages and disadvantages of the main methods used for improving the filtration characteristics of the productive horizon, when mining the uranium deposits by the borehole method, have been studied. Samples of sedimentation from the productive horizon are taken at the uranium deposit of the Shu-Syrasu depression. The quantitative and qualitative parameters, as well as the peculiarities of the mineral compositions have been determined by the X-ray phase method. A methodology has been developed and laboratory experiments have been conducted on the treatment of sedimentation samples by the drop method using various compositions of selected decolmating solutions. The microscopic method is used to determine the structure and peculiarities of sedimentation before and after treatment with various decolmating solutions. Findings. The effectiveness of the main methods used to improve the filtration characteristics of seams in the uranium deposits, mined by the borehole method, has been determined. The structure and composition of sedimentation, which causes a decrease in the filtration characteristics of the productive horizon, have been determined. To destroy and prevent the sedimentation in the productive horizon, an effective composition of a special decolmating solution using ammonium hydrogen fluoride with the addition of sulphuric acid and surfactants has been selected. An effective method for increasing the filtration characteristics of the productive horizon with the use of special decolmating solutions has been developed and scientifically substantiated. Originality. The use of special decolmating solutions based on ammonium hydrogen fluoride with the addition of sulphuric acid and surfactants according to the developed methodology allows to effectively destroy and prevent sedimentation in the productive horizon of borehole uranium ore mining. Practical implications. The use of the developed decolmating solution and a special methodology for the intensification of borehole uranium mining can reduce the operating costs of its production. This increases the ecological and industrial safety of the work to intensify the leaching of uranium ores.

Natural background gamma radiation levels were estimated in indoors and outdoors of the surrounding seven villages of Devarakonda town, these villages are at a distance of 15 to 20 kms from the proposed uranium mining area, in the Telangana State, with µR survey meter and Thermoluminescence Dosimeters (TLDs). The estimated average absorbed dose rates in the indoors and outdoors with survey meter were found to be 233 ± 68 nGy h−1 and 204 ± 55 nGy h−1, respectively, and estimated average gamma radiation levels with TLDs in the indoors were found to be 318 ± 48 nGy h−1. The estimated dose rate is about four times higher than the national average. The distribution of gamma activity concentration in the study area is observed to be followed normal distribution. An attempt has been made to find out the cause of gamma radiation levels in the dwellings and calculated the effective dose rate due to gamma radiation levels to the public living in these villages.

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.

The article considers the study of the radiation safety of uranium mining enterprises, since in the process of mining and processing of uranium ores a significant amount of radionuclides enter the environment, as well as methods for the absorption of radionuclides using sorbents (bentonites).

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

This paper gives an insight into the assessment of water quality in and around the Tummalapalle Uranium deposit. A total of 19 groundwater samples were collected in the study area and the chemical ...

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.

Uranium mining and ore processing are known to be harmful to the environment and human health if the waste generated is not managed properly. The aim of the present study is to determine the radiol...

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

In the context of proposed uranium mining area, it is very important to evaluate the presence of certain trace metals in groundwater around a proposed uranium mining area at Peddagattu and Seripally areas of Nalgonda district, Telangana (India). The concentrations of certain metals (Cu, Zn, Ni, Pb, Fe, Mn, Cd, Co, Sr, Ba, Cr, Cs and As) were measured in 37 groundwater locations and 10 surface water locations for seven times during 2 years around proposed uranium mining areas. The risk of the chemical toxicant [may be characterized using a hazard quotient (HQ)] is calculated by the results obtained during the study. The HQs of both groundwater (37) and surface water (10) all the considered trace metals were well below the threshold value of 1 as suggested by USEPA.

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.

The spatial distribution of six heavy metals (Cd, As, Zn, Pb, Cr, and Cu) in the soil of a decommissioned uranium mining area was investigated and their potential environmental risk was assessed. S...

Meteorological elements affecting radioactive contamination of the environment, each indicator has a different weight in the formation of the radioactive background. The strongest influence on the spread of radioactive contamination have winds. Influenced also different rainfall and the permeability of the atmospheric layer to solar radiation reaching us. The other meteorological components have a negligible impact on the spread of radioactive rays, particles and isotopes and therefore in further research we will ignore them and will not recognize their influence on climate radioactive background. In the analysis of meteorological elements that influence the spread of radioactive particles and radioactive isotopes in Bulgaria are mainly analyzed winds and air currents that form in the airspace over Bulgaria. These are the main weather elements that most influence the climate of the radioactive background. Another element that influences is precipitation in its various manifestations - horizontal and vertical type and depending on the physical condition of the water. The other meteorological elements because of their vile influence of the radiation situation will exclude them from the factors shaping the natural indicators of the state of the atmosphere, water and pochvata.Analizat is made on the basis of detailed statistics on the direction and strength of the wind and air currents over the territory of Bulgaria in the last 30 years. In addition to daily data for the period after 2009 have used aggregated figures on the direction and strength of winds, and near the concerned areas and over throughout our country and in adjacent border areas. This data is used for a period of 20 years, which is enough to capture the trends of change of atmospheric masses and neighboring aquatic and terrestrial surfaces. I must point out that monitoring of air masses over the past 25 years gives us only the main trends and directions, but as we all know, these processes are too dynamic and not subject to cyclic steady repetition and prediction. So at the same time made extensive research and data processing should not disable the constant monitoring of our environment and its parametri.Kato main potential sources of radioactive contamination are discussed nuclear power in Europe. In analyzing the results of the forecast movements of air masses and spreading radioactive particles consequently observed that apart from the NPP "Kozloduy" and adjacent to Bulgaria Kozloduy "Black Water" at different intervals of time radioactive contamination may occur and result of an accident in other NPPs in Europe.

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.

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.

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.

Introdução: A radioproteção tem como foco a proteção dos seres humanos e seus descendentes e a proteção do meio ambiente. A proteção ambiental sempre foi feita de forma indireta por meio da proteção do ser humano no meio ambiente. Essa abordagem antropocêntrica tem várias deficiências. Em sua recomendação de 2007, a Comissão Internacional de Proteção Radiológica - ICRP aponta para a necessidade de uma radioproteção ser feita no meio ambiente. Conclusão: Os valores de concentração de atividade estiveram dentro das variações para emissores alfa na literatura e, com as taxas de estimativa de dose, nenhum efeito biológico relevante era esperado.

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.

Made available in DSpace on 2020-12-12T01:21:06Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-01-01. Added 1 bitstream(s) on 2021-07-15T14:37:48Z : No. of bitstreams: 1 S0001-37652020000101102.pdf: 10826198 bytes, checksum: 8e09377d2c69a20ff6e2ad75b1c75e83 (MD5) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ) The Generalized Integral Transform Technique (GITT) was employed to simulate transient one-dimensional flow in variably saturated porous media, as well as radioactive waste transport within different layers (a solid waste pile, nearby soil, and a granular aquifer) towards the edge of a uranium mining installation under institutional control. Computational codes, written using the Mathematica software system, were implemented and tested for solution of the coupled advection-dispersion equations for an arbitrary number of daughter products within a radioactive chain migrating in saturated and unsaturated soil layers. The computer simulations were verified in great detail against results obtained using the built-in routine NDSolve of the Mathematica platform and the HYDRUS-1D software system. The present work reports the main results for 238U chain radionuclide transport using data extracted from a safety assessment of solid waste repositories at a uranium mining and milling installation in Caetité, state of Bahia, Brazil, operated by INB (Indústrias Nucleares do Brasil). Concentration evolutions of the various radionuclides obtained with the simulations were analyzed for five different cases to explore variations in the infiltration and recharge rates, the effect of assuming physical equilibrium or non-equilibrium transport conditions, and of different initial concentrations of some of the radionuclides. LabMEMS Mechanical Eng. Dept. POLI & COPPE Federal University of Rio de Janeiro, Rua Muniz de Aragão, no. 360, Bloco 4, CT-2, Cidade Universitária General Directorate for Nuclear and Technological Development DGDNTM, Brazilian Navy, Ed. 23 do AMRJ, Rua da Ponte, s/n, Centro Nuclear Eng. Dept. POLI & COPPE Federal University of Rio de Janeiro UFRJ, Rua Horácio Macedo, Bloco G, Cidade Universitária Center for Environmental Studies CEA São Paulo State University UNESP, R. 16 B, 99-193, Bela Vista Chemical Eng. Dept. Federal University of Pará UFPA Instituto de Tecnologia, Campus Guamá Center for Environmental Studies CEA São Paulo State University UNESP, R. 16 B, 99-193, Bela Vista

Concentrations of potentially toxic metals including Cd, Cu, Pb, Cr, U, Th in surface water and sediment samples collected from a river were analyzed to assess the contaminations, distribution characteristics, and sources of these metals. The contents of the metals were lower than the standard levels set by World Health Organization (WHO) for drinking water. However, U and Th contents were far beyond the background values of surface water. The concentrations of Cd, Cr, and U in sediments were higher than the background values and the Probable Effect Level (PEL) of sediment quality guidelines (SQGs) which may result in high potential harmful biological effects to aquatic ecosystems. Based on the contamination factor (CF), geo-accumulation index (Igeo), and potential ecological risk index (RI), Cd, Cr, and U were considered to be the metals that mainly contribute to the contamination of sediments. The calculation results also indicated that the sites adjacent to the uranium ore field were highly polluted. Results of cluster analysis, principal component analysis, and correlation analysis revealed that Cr, Pb, U, and Th were highly correlated with each other. These metals mainly originated from both anthropogenic sources and natural processes, especially emissions from uranium mining and quarrying, whereas Cd mostly came from anthropogenic sources (agricultural activities) of the upper reaches of the river.

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.

Historically, there have been limited international controls at the very front end of the nuclear fuel cycle, which consists of mining, processing, transportation, and conversion of natural...

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...

Purpose. To establish pre-mining indicators to assess radiological impact as a result of release of radionuclides to environment during uranium mining at Mkuju River Project radioactivity of 226Ra, 232Th and 40K in soil, plants, fruits and cereals. Methods. The High Purity Germanium detector was used to determine the radioactivity and the data were subsequently used to establish soil to plant transfer factors and annual effective dose. Findings. The results revealed a strong positive correlation (r) of 0.947 and 0.950 for 226Ra and 232Th, respectively, between values determined in soils and plants. Implicit in these finding is that the distribution of radionuclides in soils is directly proportional to the corresponding radionuclides in plants. Originality. The roots of wild grass had the highest specific radioactivity (Bqkg-1) for 226Ra (2.15 ± 0.02), 232Th (1.43 ± 0.02) and 40K (198.16 ± 1.72) and the roots of cabbage had the highest values for 226Ra (1.38 ± 0.04), 232Th (1.34 ± 0.03) and 40K (146.12 ± 1.02) among the food crops, an indication of a higher ability to uptake radionuclides from soil. Similarly, since the TFs were found higher in wild grass for 226Ra (0.0533 ± 0.04), 232Th (0.0374 ± 0.002) and 40K (0.5297 ± 0.05) and cabbage for 226Ra (0.0362 ± 0.03), 232Th (0.0360 ± 0.001) and 40K (0.4173 ± 0.05). Practical implications. It is an evident that these plants can serve as good bio indicators to assess release of radionuclides from inside the mining site to the public domain. Moreover, the annual effective dose (mSvy-1) for 40K (0.23 ± 0.02), 226Ra (0.046±0.004) and 232Th (0.073 ± 0.006) in edible crops when consumed in the vicinity of the MRP before the mining operations were, as expected, insignificant.

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.

Following its discovery, more than 200 years ago, uranium found useful applications in a number of various areas especially those related to industry, research and also medicine. The uranium history has been closely associated with the discovery of radioactivity which opened the door to the separation and later to the production of many useful radionuclides. The importance of uranium was recognized particularly owing to its ability to undergo fission process leading to the release of much more energy than it is possible to acquire from chemical reactions. Namely, the fission has been widely utilized in nuclear reactors to generate electricity in nuclear power plants. Such reactors are also used to produce a great number of radionuclides and for fundamental and applied research. Unfortunately, the fission has also been used for military purpose that resulted later in the construction of weapons of mass destruction. The extensive demand for uranium led to the expansion of uranium mining, milling and processing which led to some problems including exposure of workers and the radioactive contamination of the environment. The health effects associated with uranium and its compounds were fully recognized only during the last 70 years. This resulted in worldwide adoption of the relevant strict measures for adequate protection of people and the environment in line with the latest international safety requirements. The data concerning these health effects were acquired from numerous epidemiological studies based on which relevant safety procedures have been developed and implemented. The chapter presents a short overview of the uranium’s early history, which began in Jachymov, together with uranium mining, uses and the assessment of its biological effects based on epidemiological studies.

Radiological assessment was carried out at the mining tunnels (El Missikat and EL Aradiya tunnels) in Egypt due to exposure to radon (222Rn), thoron (220Rn) and gamma radiation. 222Rn/220Rn measurements were carried out with two techniques; instantaneous (active) and discriminative (passive) radon and thoron solid-state nuclear track detectors were used for longer representative measurements. The detectors were exposed for a long time inside the tunnels. The results showed that radon and thoron in general, are very high due to non-ventilation drafts inside the tunnels and gamma radiation was low. The total annual effective doses exceeded the permissible limit 20 mSv year−1. According to IAEA recommendations, the two tunnels are regulated and controlled areas. A radiation hazard could be associated with exceptional situations, such as elevated exposures to ionizing radiation at tunnels, so work within these tunnels must be prevented until the application of IAEA regulation for radiation protection standards. The exposure for radon and thoron gases for a long time can damage the body cells and cause cancer.

Focussing on the mining of uranium and its subsequent milling and refining operations, this chapter presents a highly critical review of the few known and many unknown effects of the nuclear industry upon the environment and the health of humans. As the effects will persist for as long as the wastes from the process, the chapter concludes with questions about the role of uranium mining in the long range of pollution with ionizing radiation.

The Ontario uranium miners study is a large (n = 28 546) cohort with low levels of radon exposure relative to other uranium miner cohorts. Multiple methods were used over time to estimate annual occupational exposure to radon daughters including: mine-specific extrapolations by mining engineers, area sampling in limited areas of the mines combined with approximate working time and lastly, consistent exposure sampling in different locations of the mine combined with workers' time cards. Nonetheless, estimating exposures involves assumptions that lead to some uncertainty in occupational exposure characterisation arising from the assessment approach and variability within workplace, over time and by individual. An evaluation of the total uncertainty associated with radon daughter exposure estimation in Ontario miners over time has not been conducted. The objective of this study was to identify the contributing sources and assess the total uncertainty associated with estimating occupational radon daughter exposure among underground Ontario uranium miners over the course of uranium mining. The five sources of radon daughter exposure uncertainty evaluated were: natural variations in radon concentration, estimation of working time, precision of the radon measurement method, unintended errors during sampling, and record keeping and transcription of exposure data. These sources were examined separately for the period 1958 to 1967 and then 1968 onward due to changes in radon daughter concentration measurement practices between these periods. The magnitude of uncertainty associated with each of these sources over time were determined by reviewing historical literature on uranium mining in Ontario as well as through expert advice. Using the root sum square method, the total radon daughter exposure uncertainty was found to be 53 to 67% in the earlier period of uranium mining from 1958 to 1967. This decreased to 31 to 39% for the period 1968 to 1996 with natural variations of radon daughter concentrations in mines accounting for the largest percentage of uncertainty. This assessment provides an initial step in understanding the effect of exposure uncertainty on risk estimates. The impact of this uncertainty on the dose-response relationship between radon exposure and cancer risk will be assessed in future work.