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Sahu P, Beg IA, Panigrahi DC. An investigation of 222Rn exhalation rates from backfill mill tailings influenced by the different parameters in underground uranium mines. Radiat Phys Chem Oxf Engl 1993 2022. [DOI: 10.1016/j.radphyschem.2022.110648] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Estimation of Natural Radionuclides and Rare Earth Elements Concentration of the Rocks of Abu Khuruq Ring Complex, Egypt. Symmetry (Basel) 2019. [DOI: 10.3390/sym11081041] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The naturally occurring radionuclides (radium-226, thorium-232, potassium-40 and radon-222) were investigated in the alkaline rocks of Abu Khuruq Ring, southern Eastern Desert, Egypt. A high-resolution germanium detector was used for the detection of 40K, 232Th, and 226Ra (Canberra, GR4020 model) while 222Rn concentration was measured by the Alpha-Guard Saphymo GmbH system, model PQ 2000 (AG). Major and rare earth elements (REEs) were assessed using the inductively coupled plasma mass spectrometry and atomic emission spectrometry techniques. Positive correlations were observed between REEs, indicating symmetrical chemical properties and their overall presence in the parent material—also, a positive correlation was observed between effective radium content and radon concentrations pointing to the strong linear dependency between both contents in the studied rocks. The average values of activity concentration of 40K, 232Th, 226Ra, and 222Rn were less than the suggested level by a factor of 1.38%, 3.16%, 2.09%, and 1.16%, respectively. Significant variations were found among the radiological hazards parameters, e.g., the mean value of the annual effective dose (0.55 mSv y−1) was more than the global reference value (0.41 mSv y−1) by a factor of 1.34. The calculated average value of the gamma index was 0.90, and that of the alpha index was 0.37. Hex, Hin and Raeq showed fewer average values than the standard values of unity and 370 Bq kg−1, respectively.
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Deciphering and Predicting Microscale Controls on Radon Production in Soils, Sediments and Rock. SOIL SYSTEMS 2018. [DOI: 10.3390/soilsystems2020030] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Bollhöfer A, Doering C. Long-term temporal variability of the radon-222 exhalation flux from a landform covered by low uranium grade waste rock. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2016; 151 Pt 3:593-600. [PMID: 26100675 DOI: 10.1016/j.jenvrad.2015.06.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2015] [Revised: 06/03/2015] [Accepted: 06/06/2015] [Indexed: 06/04/2023]
Abstract
Radon-222 exhalation flux densities from two different substrates of several metres thickness, waste rock and waste rock mixed with approximately 30% lateritic material, were measured over a period of five years in the wet-dry tropics of Northern Australia. Fourteen measurement campaigns using activated charcoal canisters (n > 1000) covered both dry and wet seasons and showed differences in seasonal and long term trends of the (222)Rn exhalation flux densities normalised to the (226)Ra activity concentrations of the substrate. Dry season (222)Rn exhalation was generally higher for the mixed substrate, due to the larger fraction of fines. Seasonality established within the first year of landform construction on the mixed substrate, due to the higher water holding capacity of the lateritic material. In contrast, waste rock only shows no seasonality until years four and five after construction, when average normalised dry season (222)Rn exhalation flux densities from waste rock increase to values (0.47 ± 0.06 mBq m(-2) s(-1) per Bq kg(-1)) similar to the mixed substrate (0.64 ± 0.08 mBq m(-2) s(-1) per Bq kg(-1)), likely due to an increase in fines from rapid weathering of the schistose waste rock. Volumetric water content has been used to parametrize relative (222)Rn exhalation and we determined that wet season (222)Rn exhalation is about 40% of the dry season exhalation.
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Affiliation(s)
- Andreas Bollhöfer
- Environmental Research Institute of the Supervising Scientist (eriss), GPO Box 461, Darwin, NT 0801, Australia.
| | - Che Doering
- Environmental Research Institute of the Supervising Scientist (eriss), GPO Box 461, Darwin, NT 0801, Australia
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Kümmel M, Dushe C, Müller S, Gehrcke K. Outdoor (222)Rn-concentrations in Germany - part 2 - former mining areas. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2014; 132:131-137. [PMID: 24508448 DOI: 10.1016/j.jenvrad.2014.01.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2013] [Revised: 01/17/2014] [Accepted: 01/19/2014] [Indexed: 06/03/2023]
Abstract
In the German Federal States of Saxony, Saxony-Anhalt and Thuringia, centuries of mining and milling activities resulted in numerous residues with increased levels of natural radioactivity such as waste rock dumps and tailings ponds. These may have altered potential radiation exposures of the population significantly. Especially waste rock dumps from old mining activities as well as 20th century uranium mining may, due to their radon ((222)Rn) exhalation capacity, lead to significant radiation exposures. They often lie close to or within residential areas. In order to study the impact on the natural radon level, the Federal Office for Radiation Protection (BfS) has run networks of radon measurement points in 16 former mining areas, together with 2 networks in regions not influenced by mining for comparison purposes. Representative overviews of the long-term outdoor radon concentrations could be established including estimates of regional background concentrations. Former mining and milling activities did not result in large-area impacts on the outdoor radon level. However, significantly increased radon concentrations were observed in close vicinity of shafts and large waste rock dumps. They are partly located in residential areas and need to be considered under radiation protection aspects. Examples are given that illustrate the consequences of the Wismut Ltd. Company's reclamation activities on the radon situation.
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Affiliation(s)
- M Kümmel
- Bundesamt für Strahlenschutz, 38226 Salzgitter, Germany.
| | - C Dushe
- Bundesamt für Strahlenschutz, 38226 Salzgitter, Germany
| | - S Müller
- Bundesamt für Strahlenschutz, 38226 Salzgitter, Germany
| | - K Gehrcke
- Bundesamt für Strahlenschutz, 38226 Salzgitter, Germany
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Alharbi SH, Akber RA. Radon-222 activity flux measurement using activated charcoal canisters: revisiting the methodology. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2014; 129:94-99. [PMID: 24412530 DOI: 10.1016/j.jenvrad.2013.12.021] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2013] [Revised: 12/21/2013] [Accepted: 12/23/2013] [Indexed: 06/03/2023]
Abstract
The measurement of radon ((222)Rn) activity flux using activated charcoal canisters was examined to investigate the distribution of the adsorbed (222)Rn in the charcoal bed and the relationship between (222)Rn activity flux and exposure time. The activity flux of (222)Rn from five sources of varying strengths was measured for exposure times of one, two, three, five, seven, 10, and 14 days. The distribution of the adsorbed (222)Rn in the charcoal bed was obtained by dividing the bed into six layers and counting each layer separately after the exposure. (222)Rn activity decreased in the layers that were away from the exposed surface. Nevertheless, the results demonstrated that only a small correction might be required in the actual application of charcoal canisters for activity flux measurement, where calibration standards were often prepared by the uniform mixing of radium ((226)Ra) in the matrix. This was because the diffusion of (222)Rn in the charcoal bed and the detection efficiency as a function of the charcoal depth tended to counterbalance each other. The influence of exposure time on the measured (222)Rn activity flux was observed in two situations of the canister exposure layout: (a) canister sealed to an open bed of the material and (b) canister sealed over a jar containing the material. The measured (222)Rn activity flux decreased as the exposure time increased. The change in the former situation was significant with an exponential decrease as the exposure time increased. In the latter case, lesser reduction was noticed in the observed activity flux with respect to exposure time. This reduction might have been related to certain factors, such as absorption site saturation or the back diffusion of (222)Rn gas occurring at the canister-soil interface.
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Affiliation(s)
- Sami H Alharbi
- School of Physics and Chemical Science, Queensland University of Technology, 2 George Street, Brisbane, Qld 4000, Australia.
| | - Riaz A Akber
- School of Physics and Chemical Science, Queensland University of Technology, 2 George Street, Brisbane, Qld 4000, Australia
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Mudd GM. The future of Yellowcake: a global assessment of uranium resources and mining. THE SCIENCE OF THE TOTAL ENVIRONMENT 2014; 472:590-607. [PMID: 24317167 DOI: 10.1016/j.scitotenv.2013.11.070] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2013] [Revised: 10/21/2013] [Accepted: 11/11/2013] [Indexed: 06/02/2023]
Abstract
Uranium (U) mining remains controversial in many parts of the world, especially in a post-Fukushima context, and often in areas with significant U resources. Although nuclear proponents point to the relatively low carbon intensity of nuclear power compared to fossil fuels, opponents argue that this will be eroded in the future as ore grades decline and energy and greenhouse gas emissions (GGEs) intensity increases as a result. Invariably both sides fail to make use of the increasingly available data reported by some U mines through sustainability reporting - allowing a comprehensive assessment of recent trends in the energy and GGE intensity of U production, as well as combining this with reported mineral resources to allow more comprehensive modelling of future energy and GGEs intensity. In this study, detailed data sets are compiled on reported U resources by deposit type, as well as mine production, energy and GGE intensity. Some important aspects included are the relationship between ore grade, deposit type and recovery, which are crucial in future projections of U mining. Overall, the paper demonstrates that there are extensive U resources known to meet potential short to medium term demand, although the future of U mining remains uncertain due to the doubt about the future of nuclear power as well as a range of complex social, environmental, economic and some site-specific technical issues.
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Affiliation(s)
- Gavin M Mudd
- Environmental Engineering, Dept of Civil Eng, Monash University, Wellington Rd, Clayton, VIC 3800 Australia.
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Bollhöfer A, Beraldo A, Pfitzner K, Esparon A, Doering C. Determining a pre-mining radiological baseline from historic airborne gamma surveys: a case study. THE SCIENCE OF THE TOTAL ENVIRONMENT 2014; 468-469:764-773. [PMID: 24076500 DOI: 10.1016/j.scitotenv.2013.09.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2013] [Revised: 08/27/2013] [Accepted: 09/01/2013] [Indexed: 06/02/2023]
Abstract
Knowing the baseline level of radioactivity in areas naturally enriched in radionuclides is important in the uranium mining context to assess radiation doses to humans and the environment both during and after mining. This information is particularly useful in rehabilitation planning and developing closure criteria for uranium mines as only radiation doses additional to the natural background are usually considered 'controllable' for radiation protection purposes. In this case study we have tested whether the method of contemporary groundtruthing of a historic airborne gamma survey could be used to determine the pre-mining radiological conditions at the Ranger mine in northern Australia. The airborne gamma survey was flown in 1976 before mining started and groundtruthed using ground gamma dose rate measurements made between 2007 and 2009 at an undisturbed area naturally enriched in uranium (Anomaly 2) located nearby the Ranger mine. Measurements of (226)Ra soil activity concentration and (222)Rn exhalation flux density at Anomaly 2 were made concurrent with the ground gamma dose rate measurements. Algorithms were developed to upscale the ground gamma data to the same spatial resolution as the historic airborne gamma survey data using a geographic information system, allowing comparison of the datasets. Linear correlation models were developed to estimate the pre-mining gamma dose rates, (226)Ra soil activity concentrations, and (222)Rn exhalation flux densities at selected areas in the greater Ranger region. The modelled levels agreed with measurements made at the Ranger Orebodies 1 and 3 before mining started, and at environmental sites in the region. The conclusion is that our approach can be used to determine baseline radiation levels, and provide a benchmark for rehabilitation of uranium mines or industrial sites where historical airborne gamma survey data are available and an undisturbed radiological analogue exists to groundtruth the data.
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Affiliation(s)
- Andreas Bollhöfer
- Environmental Research Institute of the Supervising Scientist (ERISS), Australian Government, Department of Sustainability, Environment, Water, Population and Communities, PO Box 461, Darwin, NT 0801, Australia.
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Moharram B, Suliman M, Zahran N, Shennawy S, El Sayed A. 238U, 232Th content and radon exhalation rate in some Egyptian building materials. ANN NUCL ENERGY 2012. [DOI: 10.1016/j.anucene.2012.03.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Byrdina S, Revil A, Pant SR, Koirala BP, Shrestha PL, Tiwari DR, Gautam UP, Shrestha K, Sapkota SN, Contraires S, Perrier F. Dipolar self-potential anomaly associated with carbon dioxide and radon flux at Syabru-Bensi hot springs in central Nepal. ACTA ACUST UNITED AC 2009. [DOI: 10.1029/2008jb006154] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Hassan NM, Ishikawa T, Hosoda M, Sorimachi A, Tokonami S, Fukushi M, Sahoo SK. Assessment of the natural radioactivity using two techniques for the measurement of radionuclide concentration in building materials used in Japan. J Radioanal Nucl Chem 2009. [DOI: 10.1007/s10967-009-0050-6] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Lawrence CE, Akber RA, Bollhöfer A, Martin P. Radon-222 exhalation from open ground on and around a uranium mine in the wet-dry tropics. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2009; 100:1-8. [PMID: 18995934 DOI: 10.1016/j.jenvrad.2008.09.003] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2007] [Revised: 08/06/2008] [Accepted: 09/19/2008] [Indexed: 05/27/2023]
Abstract
Radon-222 exhalation from the ground surface depends upon a number of variables such as the 226Ra activity concentration and its distribution in soil grains; soil grain size; soil porosity, temperature and moisture; atmospheric pressure, rainfall and temperature. In this study, 222Rn exhalation flux density measurements within and around the Ranger uranium mine in northern Australia were performed to investigate the effect of these variables within a tropical region. Measurements were taken at the waste rock dumps, ore stockpiles, mine pits, and at sites where effluent water with elevated 226Ra concentration has been spray irrigated over land, as well as at sites outside the mine. The sites selected represented a variety of geomorphic regions ranging from uranium-bearing rocks to ambient soils. Generally, wet season rains reduced 222Rn exhalation but at a few sites the onset of rains caused a step rise in exhalation flux densities. The results show that parameters such as 226Ra activity concentration, soil grain size and soil porosity have a marked effect on 222Rn flux densities. For similar geomorphic sites, 226Ra activity concentration is a dominant factor, but soil grain size and porosity also influence 222Rn exhalation. Surfaces with vegetation showed higher exhalation flux densities than their barren counterparts, perhaps because the associated root structure increases soil porosity and moisture retention. Repeated measurements over one year at eight sites enabled an analysis of precipitation and soil moisture effects on 222Rn exhalation. Soil moisture depth profiles varied both between seasons and at different times during the wet season, indicating that factors such as duration, intensity and time between precipitation events can influence 222Rn flux densities considerably.
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Affiliation(s)
- Cameron E Lawrence
- School of Physical and Chemical Sciences, Queensland University of Technology, 2 George Street, Brisbane Q 4000, Australia.
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HASSAN NM, HOSODA M, ISHIKAWA T, SORIMACHI A, SAHOO SK, TOKONAMI S, FUKUSHI M. Radon Migration Process and Its Influence Factors; Review. ACTA ACUST UNITED AC 2009. [DOI: 10.5453/jhps.44.218] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Affiliation(s)
- Nabil M. HASSAN
- School of Radiological Sciences, Tokyo Metropolitan University
- Research Centre for Radiation Protection, National Institute of Radiological Sciences
- Department of Physics, Faculty of Science, University of Zagazig
| | - Masahiro HOSODA
- Research Centre for Radiation Protection, National Institute of Radiological Sciences
| | - Tetsuo ISHIKAWA
- Research Centre for Radiation Protection, National Institute of Radiological Sciences
| | - Atsuyuki SORIMACHI
- Research Centre for Radiation Protection, National Institute of Radiological Sciences
| | - Sarata K. SAHOO
- Research Centre for Radiation Protection, National Institute of Radiological Sciences
| | - Shinji TOKONAMI
- Research Centre for Radiation Protection, National Institute of Radiological Sciences
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Mudd GM. Radon releases from Australian uranium mining and milling projects: assessing the UNSCEAR approach. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2008; 99:288-315. [PMID: 17913316 DOI: 10.1016/j.jenvrad.2007.08.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2007] [Revised: 08/10/2007] [Accepted: 08/13/2007] [Indexed: 05/17/2023]
Abstract
The release of radon gas and progeny from the mining and milling of uranium-bearing ores has long been recognised as a potential radiological health hazard. The standards for exposure to radon and progeny have decreased over time as the understanding of their health risk has improved. In recent years there has been debate on the long-term releases (10,000 years) of radon from uranium mining and milling sites, focusing on abandoned, operational and rehabilitated sites. The primary purpose has been estimates of the radiation exposure of both local and global populations. Although there has been an increasing number of radon release studies over recent years in the USA, Australia, Canada and elsewhere, a systematic evaluation of this work has yet to be published in the international literature. This paper presents a detailed compilation and analysis of Australian studies. In order to quantify radon sources, a review of data on uranium mining and milling wastes in Australia, as they influence radon releases, is presented. An extensive compilation of the available radon release data is then assembled for the various projects, including a comparison to predictions of radon behaviour where available. An analysis of cumulative radon releases is then developed and compared to the UNSCEAR approach. The implications for the various assessments of long-term releases of radon are discussed, including aspects such as the need for ongoing monitoring of rehabilitation at uranium mining and milling sites and life-cycle accounting.
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Affiliation(s)
- Gavin M Mudd
- Institute for Sustainable Water Resources, Department of Civil Engineering, Monash University, Wellington Road, Clayton, VIC 3800, Australia.
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