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Wang H, Xie B, Wang Y, Wen J, Hong C. Influence of temperature on the radon concentration distribution in ramp under low-speed wind field: A numerical simulation study. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2024; 272:107331. [PMID: 38008047 DOI: 10.1016/j.jenvrad.2023.107331] [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: 07/11/2023] [Revised: 11/08/2023] [Accepted: 11/09/2023] [Indexed: 11/28/2023]
Abstract
By introducing the parameters of radon exhalation rate and radon diffusion coefficient, the distribution of radon concentration field on ramp under the condition of superposition of temperature field and flow field is simulated. The simulation results show that the distribution of radon concentration in the ramp under the condition of low-speed ventilation is greatly affected by the temperature field and flow field, and the change of radon exhalation caused by temperature is the main factor leading to the change of radon concentration in the ramp. The change of temperature will cause the overall increase of radon concentration in the ramp. Under the condition of constant flow field, the radon concentration in the chamber is more than two times higher than the average radon concentration in the ramp. Some areas severely exceeded the limit.
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Affiliation(s)
- Hong Wang
- School of Resources, Environmental and Safety Engineering, University of South China, Hengyang, 421001, China; School of Nuclear Science and Technology, University of South China, Hengyang, 421001, China; Hunan Province Engineering Technology Research Center of Uranium Tailings Treatment, University of South China, Hengyang, 421001, China
| | - Bingbing Xie
- School of Resources, Environmental and Safety Engineering, University of South China, Hengyang, 421001, China; Hunan Province Engineering Technology Research Center of Uranium Tailings Treatment, University of South China, Hengyang, 421001, China
| | - Yuhang Wang
- School of Resources, Environmental and Safety Engineering, University of South China, Hengyang, 421001, China; Hunan Province Engineering Technology Research Center of Uranium Tailings Treatment, University of South China, Hengyang, 421001, China
| | - Jiale Wen
- School of Resources, Environmental and Safety Engineering, University of South China, Hengyang, 421001, China; Hunan Province Engineering Technology Research Center of Uranium Tailings Treatment, University of South China, Hengyang, 421001, China
| | - Changshou Hong
- School of Resources, Environmental and Safety Engineering, University of South China, Hengyang, 421001, China; Hunan Province Engineering Technology Research Center of Uranium Tailings Treatment, University of South China, Hengyang, 421001, China.
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Miklyaev PS, Petrova TB, Maksimovich NG, Krasikov AV, Klimshin AV, Shchitov DV, Sidyakin PA, Tsebro DN, Meshcheriakova OY. Comparative studies on radon seasonal variations in various undeground environments: Cases of abandoned Beshtaugorskiy uranium mine and Kungur Ice Cave. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2024; 272:107346. [PMID: 38043218 DOI: 10.1016/j.jenvrad.2023.107346] [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: 07/17/2023] [Revised: 08/30/2023] [Accepted: 11/17/2023] [Indexed: 12/05/2023]
Abstract
It is well known that one of the most important risk factors in underground environment is the harmful effects of radon. The reasons for strong seasonal fluctuations in radon content in underground environments remain not fully understood. The purpose of this article is to improve existing ideas about this phenomenon. The article presents the results of a study of radon transport in two different underground spaces - the Beshtaugorskiy uranium mine (North Caucasus) and the Kungur Ice Cave (Middle Ural). We have used the direct measurements of the equilibrium equivalent concentration (EEC) of radon progeny in air, as well as the air flow velocity. A very wide range and strong seasonal variations in the radon levels have been recorded in both cases. The EEC has a range of 11-6653 by Bq m-3 and 10-89,020 Bq m-3 in the Kungur cave and the Beshtaugorskiy mine, respectively. It has been established that seasonal fluctuations in radon levels both in the mine and in the cave are caused by the same process - convective air circulation in the underground space due to the temperature difference between the mountain massif and the atmosphere (so called chimney effect). Overall, these results indicate that due to convective air circulation, underground spaces are periodically intensively ventilated with atmospheric air, and then, on the contrary, they are filled with radon-enriched air that seeps into caves or adits from rocks and ores. In both cases, the EEC of radon progeny exceeds the permissible level for the population and workers. The results of this study highlight the need for the development of measures to limit the presence of people in the surveyed underground spaces.
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Affiliation(s)
- Petr S Miklyaev
- Sergeev Institute of Environmental Geoscience Russian Academy of Sciences (IEG RAS), 13/2 Ulansky Str., 101000, Moscow, Russia.
| | - Tatiana B Petrova
- Lomonosov Moscow State University, Faculty of Chemistry, Department of Radiochemistry, 1/3 Leninskie Gory, GSP-1, 119991, Moscow, Russia
| | | | - Alexey V Krasikov
- Mining Institute of the Ural Branch of the Russian Academy of Sciences, 78a Sibirskaya Str., 614007, Perm, Russia
| | | | - Dmitriy V Shchitov
- North Caucasus Federal University, Pyatigorsk Branch, Engineering Faculty, Department of Construction, 46a Ermolov Str., 357500, Pyatigorsk, Russia
| | - Pavel A Sidyakin
- North Caucasus Federal University, Pyatigorsk Branch, Engineering Faculty, Department of Construction, 46a Ermolov Str., 357500, Pyatigorsk, Russia
| | - Dmitriy N Tsebro
- North Caucasus Federal University, Pyatigorsk Branch, Engineering Faculty, Department of Construction, 46a Ermolov Str., 357500, Pyatigorsk, Russia
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Fijałkowska-Lichwa L, Przylibski TA. Monthly and quarterly correction factors for determining the mean annual radon concentration in the atmosphere of underground workplaces in Poland. ENVIRONMENTAL GEOCHEMISTRY AND HEALTH 2023; 45:1475-1498. [PMID: 35501524 DOI: 10.1007/s10653-022-01280-2] [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: 12/03/2021] [Accepted: 04/08/2022] [Indexed: 06/14/2023]
Abstract
The aimed of the work was estimated the value (level) of mean annual 222Rn activity concentration in an underground space based on monthly (k1m) and quarterly (k3m) correction factors. The calculations of factors were developed with the assumption that measurements will be conducted for at least 1 month or a quarter of a year. Radon monitoring to confirm the calculated values was carried out continuously from 2008 to 2019 and verification was made on real data obtained in 2020. The estimated mean annual 222Rn activity concentration for spaces with natural air exchange depends on factors k1m and for mechanically ventilated spaces-k3m. The k1m for the first group varies from 1.2 to 3.3 between January and March, and between October and December. In the remaining months, k1m assumes the values from 0.6 to 0.8. In spaces where natural air exchange with the atmosphere is not impeded by airlocks, the k1m takes the values of 1.0-1.5 (I-III and X-XII), 0.7-0.8 (V-IX), and 1.0 (IV). For spaces with mechanical ventilation, the k3m is characterized by values in the range of 1.3-1.4 (I and IV quarter), and 0.9 in the others. In spaces with an unknown ventilation method or when the methods are mixed, the averages for both groups of correction factors can be used: k1m in the range of ≥ 1.0-1.6 (I-III and IX-XII) and < 1.0-0.7 (IV-XI), and k3m-in the range of 1.3-1.4 (I and IV quarter) and 0.9 in the others.
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Affiliation(s)
- Lidia Fijałkowska-Lichwa
- Faculty of Civil Engineering, Division of Geotechnics, Hydrotechnics, Underground Construction and Hydrological Engineering, Wrocław University of Science and Technology, Wybrzeże S. Wyspiańskiego 27, 50-370, Wrocław, Poland.
| | - Tadeusz A Przylibski
- Faculty of Geoengineering, Mining and Geology, Laboratory of Geology and Planetary Sciences, Wrocław University of Science and Technology, Wybrzeże S. Wyspiańskiego 27, 50-370, Wrocław, Poland
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Miklyaev PS, Petrova TB, Shchitov DV, Sidyakin PA, Murzabekov MA, Tsebro DN, Marennyy AM, Nefedov NA, Gavriliev SG. Radon transport in permeable geological environments. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 852:158382. [PMID: 36049692 DOI: 10.1016/j.scitotenv.2022.158382] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2022] [Revised: 08/21/2022] [Accepted: 08/25/2022] [Indexed: 05/14/2023]
Abstract
This article presents the results of a long-term soil radon and meteorological parameter monitoring study in the fault zone at Mt. Beshtau, North Caucasus, which for more than 3 years. Strong seasonal variations in the radon levels with maxima during summer and minima during winter were recorded. The values of radon exhalation and soil radon concentration have a range of 0.025-25 Bq m 2 s -1 and 1-170 kBq m -3, respectively. In addition, measurements of the air radon concentration, and direction of air movement at the adits mouths of the former uranium mine on the same mountain were carried out. Seasonal radon variations, similar to those observed in fault zones, were recorded at the mouths of adits. It was established that radon anomalies are associated with the periodic release of mine air from the fractures and tunnels into the atmosphere. Above an altitude of 900 m a. s. l., an abnormal release of radon occurs in winter, when the mine air is warmer than the surrounding atmosphere. At the altitudes below 900 m the cold radon rich air blows from the adit mouths in summer. During mine air discharge, radon concentrations in the open atmosphere locally around the adit mouth reach 600,000 Bq m-3, averaging 50,000-250,000 Bq m-3. The temporal pattern of radon fluctuations in fault zones and at the adit mouths is similar. A very close correlation between radon levels and atmospheric air temperature was observed both in the fault zone and at the adits mouths. It indicates that radon release in both cases are caused by a single mechanism. This mechanism probably is the atmospheric air circulation in shallow permeable zones due to the temperature difference between the inside mountain and ambient atmosphere.
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Affiliation(s)
- Petr S Miklyaev
- Sergeev Institute of Environmental Geoscience Russian Academy of Sciences (IEG RAS), Ulansky per. 13 build. 2, 101000 Moscow, Russia.
| | - Tatiana B Petrova
- Lomonosov Moscow State University, Faculty of Chemistry, Department of Radiochemistry, Leninskie Gory 1 build. 3, GSP-1, 119991 Moscow, Russia
| | - Dmitriy V Shchitov
- North Caucasus Federal University, Pyatigorsk Branch, Engineering Faculty, Department of Construction, Ermolov str., 46a, 357500 Pyatigorsk, Russia
| | - Pavel A Sidyakin
- North Caucasus Federal University, Pyatigorsk Branch, Engineering Faculty, Department of Construction, Ermolov str., 46a, 357500 Pyatigorsk, Russia
| | - Murat A Murzabekov
- North Caucasus Federal University, Pyatigorsk Branch, Engineering Faculty, Department of Construction, Ermolov str., 46a, 357500 Pyatigorsk, Russia
| | - Dmitriy N Tsebro
- North Caucasus Federal University, Pyatigorsk Branch, Engineering Faculty, Department of Construction, Ermolov str., 46a, 357500 Pyatigorsk, Russia
| | - Albert M Marennyy
- Research and Technical Center of Radiation-Chemical Safety and Hygiene, Shchukinskaya ul. 40, 123182 Moscow, Russia
| | - Nikolay A Nefedov
- Research and Technical Center of Radiation-Chemical Safety and Hygiene, Shchukinskaya ul. 40, 123182 Moscow, Russia
| | - Sakhayaan G Gavriliev
- Sergeev Institute of Environmental Geoscience Russian Academy of Sciences (IEG RAS), Ulansky per. 13 build. 2, 101000 Moscow, Russia; Lomonosov Moscow State University, Faculty of Chemistry, Department of Radiochemistry, Leninskie Gory 1 build. 3, GSP-1, 119991 Moscow, Russia
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Fijałkowska-Lichwa L, Przylibski TA. Assessment of occupational exposure from radon in the newly formed underground tourist route under Książ castle, Poland. RADIATION AND ENVIRONMENTAL BIOPHYSICS 2021; 60:329-345. [PMID: 33742235 PMCID: PMC8116260 DOI: 10.1007/s00411-021-00903-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Accepted: 03/08/2021] [Indexed: 05/13/2023]
Abstract
In the present study, 222Rn activity concentrations in a newly formed underground tourist route under Książ castle, Poland, were investigated for periods undisturbed and disturbed by construction works. This preliminary assessment is based on the almost 3-year long continuous measurements (28 Oct. 2016-02 Jul. 2019) done with an SRDN-3 instrument. In detail described are radon concentrations for periods of renovation (11 Aug. 2018-10 Oct. 2018), opening (15 Oct. 2018-10 Apr. 2019) and operation and monitoring (11 Apr. 2019-02 Jul. 2019) of the facility. It was observed that after the termination of construction work, when natural ventilation returned to the state preceding this work, the absolute values of radon activity concentration decreased. The mean annual radon concentrations were higher than the reference level of radon concentration in underground spaces recommended by IAEA, ICRP, and by the EU Council Directive for workplaces. They reached 1179 Bq/m3 and 943 Bq/m3 in 2017 and 2018, respectively. Cyclically recurring daily changes in radon concentrations occurred only in April and October (so-called transitional periods) and only outside the period of construction work. The results confirmed; however, that these changes need not be considered when planning the work in the tunnel. The minimum effective dose rate from radon exposure occurs in colder periods of the year, from November to the end of March, where the mean effective dose rate value was found to be 0.0003 mSv/h. In contrast, the maximum dose rate of 0.014 mSv/h was observed from April to August.
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Affiliation(s)
- Lidia Fijałkowska-Lichwa
- Faculty of Civil Engineering, Wrocław University of Science and Technology, Wybrzeże S. Wyspiańskiego 27, 50-370 Wrocław, Poland
| | - Tadeusz A. Przylibski
- Faculty of Geoengineering, Mining and Geology, Wrocław University of Science and Technology, Wybrzeże S. Wyspiańskiego 27, 50-370 Wrocław, Poland
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