scholarly journals Soil gas radon and soil permeability assessment: Mapping radon risk areas in Perak State, Malaysia

PLoS ONE ◽  
2021 ◽  
Vol 16 (7) ◽  
pp. e0254099
Author(s):  
Habila Nuhu ◽  
Suhairul Hashim ◽  
Muneer Aziz Saleh ◽  
Mohamad Syazwan Mohd Sanusi ◽  
Ahmad Hussein Alomari ◽  
...  

In this study geogenic radon potential (GRP) mapping was carried out on the bases of field radon in soil gas concentration and soil gas permeability measurements by considering the corresponding geological formations. The spatial pattern of soil gas radon concentration, soil permeability, and GRP and the relationship between geological formations and these parameters was studied by performing detailed spatial analysis. The radon activity concentration in soil gas ranged from 0.11 to 434.5 kBq m−3 with a mean of 18.96 kBq m−3, and a standard deviation was 55.38 kBq m−3. The soil gas permeability ranged from 5.2×10−14 to 5.2×10−12 m2, with a mean of 5.65×10−13 m2. The GRP values were computed from the 222Rn activity concentration and soil gas permeability data. The range of GRP values was from 0.04 to 154.08. Locations on igneous granite rock geology were characterized by higher soil radon gas activity and higher GRP, making them radon-prone areas according to international standards. The other study locations fall between the low to medium risk, except for areas with high soil permeability, which are not internationally classified as radon prone. A GRP map was created displaying radon-prone areas for the study location using Kriging/Cokriging, based on in situ and predicted measured values. The GRP map assists in human health risk assessment and risk reduction since it indicates the potential of the source of radon and can serve as a vital tool for radon combat planning.

2020 ◽  
Author(s):  
Mirsina Mousavi ◽  
Quentin Crowley

<p>A detailed investigation of geogenic radon potential (GRP) was carried out using geostatistical analysis on multiple radon-related variables to evaluate natural radiation in an area of Southeast Ireland. The geological setting of the study area includes basal Devonian sandstones and conglomerates overlying an offshoot of the Caledonian Leinster Granite, which intrudes Ordovician sediments. The Ordovician sediments contain traces of autunite (Ca(UO<sub>2</sub>)2(PO<sub>4</sub>)<sub>2</sub>·10–12H<sub>2</sub>O), which is a uranium-bearing mineral and a source of radon. To model radon release potential at different locations, a spatial regression model was developed in which soil gas radon concentration measured in-situ using a Radon RM-2 detector was considered as a response value. Proxy variables such as local geology, soil types, terrestrial gamma dose rates, radionuclide concentrations from airborne radiometric surveys, soil gas permeability, distance from major faults and a Digital Terrain Model were used as the main predictors. Furthermore, the distribution of indoor radon concentration was simulated using a soil-indoor transfer factor. Finally, the workability of the proposed GRP model was tested by evaluating the correlation between previously measured indoor radon concentrations and the estimated values by the GRP model at the same measurement locations. This model can also be used to estimate the GRPs of other areas where radon-related proxy values are available.        </p><p><strong>Keywords:</strong> Natural radiation, geogenic radon potential, geostatistical analysis, spatial regression model, indoor radon simulation</p>


2010 ◽  
Vol 10 (4) ◽  
pp. 895-899 ◽  
Author(s):  
J. Vaupotič ◽  
A. Gregorič ◽  
I. Kobal ◽  
P. Žvab ◽  
K. Kozak ◽  
...  

Abstract. The Ravne tectonic fault in north-west (NW) Slovenia is one of the faults in this region, responsible for the elevated seismic activity at the Italian-Slovene border. Five measurement profiles were fixed in the vicinity of the Ravne fault, four of them were perpendicular and one parallel to the fault. At 18 points along these profiles the following measurements have been carried out: radon activity concentration in soil gas, radon exhalation rate from ground, soil permeability and gamma dose rate. The radon measurements were carried out using the AlphaGuard equipment, and GammaTracer was applied for gamma dose rate measurements. The ranges of the obtained results are as follows: 0.9–32.9 kBq m−3 for radon concentration (CRn), 1.1–41.9 mBq m−2 s−1 for radon exhalation rate (ERn), 0.5–7.4×10-13 m2 for soil permeability, and 86–138 nSv h−1 for gamma dose rate. The concentrations of 222Rn in soil gas were found to be lower than the average for Slovenia. Because the deformation zones differ not only in the direction perpendicular to the fault but also along it, the behaviour of either CRn or ERn at different profiles differ markedly. The study is planned to be continued with measurements being carried out at a number of additional points.


Author(s):  
Javier Elío ◽  
Quentin Crowley ◽  
Ray Scanlon ◽  
Jim Hodgson ◽  
Stephanie Long ◽  
...  

Background: Indoor radon represents an important health issue to the general population. Therefore, accurate radon risk maps help public authorities to prioritise areas where mitigation actions should be implemented. As the main source of indoor radon is the soil where the building is constructed, maps derived from geogenic factors ([e.g. geogenic radon potential [GRP]) are viewed as valuable tools for radon mapping. Objectives: A novel indirect method for estimating the GRP at national/regional level is presented and evaluated in this article. Design: We calculate the radon risk solely based on the radon concentration in the soil and on the subsoil permeability. The soil gas radon concentration was estimated using airborne gamma-ray spectrometry (i.e. equivalent uranium [eU]), assuming a secular equilibrium between eU and radium (226Ra). The subsoil permeability was estimated based on groundwater subsoil permeability and superficial geology (i.e. quaternary geology) by assigning a permeability category to each soil type (i.e. low, moderate or high). Soil gas predictions were compared with in situ radon measurements for representative areas, and the resulting GRP map was validated with independent indoor radon data. Results: There was good agreement between soil gas radon predictions and in situ measurements, and the resultant GRP map identifies potential radon risk areas. Our model shows that the probability of having an indoor radon concentration higher than the Irish reference level (200 Bq m-3) increases from c. 6% (5.2% – 7.1%) for an area classified as Low risk, to c. 9.7% (9.1% – 10.5%) for Moderate-Low risk areas, c. 14% (13.4% – 15.3%) for Moderate-High risk areas and c. 26% (24.5% – 28.6%) for High risk areas. Conclusions: The method proposed here is a potential alternative approach for radon mapping when airborne radiometric data (i.e. eU) are available.


2021 ◽  
Author(s):  
Chiara Coletti ◽  
Giancarlo Ciotoli ◽  
Eleonora Benà ◽  
Erika Brattich ◽  
Giorgia Cinelli ◽  
...  

<p>In the volcanic area of the Euganean Hills district (100 km<sup>2</sup>), the indoor radon often exceeds the threshold level of 300 Bq/m<sup>3 </sup>stipulated by the Council Directive 2013/59/Euratom, thus suggesting the need to investigate the possible link between observed radon concentrations and the local geology (Trotti et al., 1998,1999; Strati et al., 2014). More recently, statistical and geostatistical analysis on rock samples identified high U, Th and K concentrations associated with areas characterised by trachyte and rhyolite lithologies (Tositti et al., 2017). With this contribution, we completed our investigation on the natural radioactivity in the Euganean Hills district extending the rocks dataset, performing on-site soil gas survey, and considering other important factors which can locally increase the radon occurrence, such as hydrothermal alterations, types of soils (e.g., geochemistry or presence of organic matters), and faults. Furthermore, we elaborated a Geogenic Radon Potential map to assess the local spatial relationships between the measured soil gas radon concentrations and seven proxy-variables: fault density (FD), total gamma radiation dose (TGDR), <sup>220</sup>Rn (Tn), digital terrain mode (SLOPE), moisture index (MI), heat load index (HLI) and soil permeability (PERM). Empirical Bayesian Regression Kriging (EBRK) was used to develop the most accurate hazard map of the considered area, thus, providing the local administration an up-to-date decisional tool for the land use planning. For the high radon emission measured, the high density of dwelling, and its geomorphological features, the Euganean Hills district represented a very meaningful case of study.  </p><p> </p><p>Trotti, F., Tanferi, A., Lanciai, M., Mozzo, P., Panepinto, V., Poli, S., Predicatori, F., Righetti, F., Tacconi, A., Zorzine, R., 1998. Mapping of areas with elevated indoor radon levels in Veneto. Radiat. Prot. Dosim. 78 (1), 11–14.</p><p>Trotti, F., Tanferi, A., Bissolo, F., Fustegato, R., Lanciai, M., Mozzo, P., Predicatori, F., Querini, P., Righetti, F., Tacconi, A., 1999. A Survey to Map Areas with Elevated Indoor Radon Levels in Veneto, Radon in the Living Environment, 19-23 April 1999, Athens, Greece, 859–868.</p><p>Strati V., Baldoncini M., Bezzon G.P, Broggini C., Buso G.P., Caciolli A., Callegari I., Carmignani L, Colonna T, Fiorentini G., Guastaldi E., Kaçeli Xhixhaf M., Mantovani F, Menegazzo R., Moub L., Rossi Alvarez C., Xhixha G., Zanon A., 2014. Total natural radioactivity, Veneto (Italy). Journal of Maps, Vol. 11, Issue 4, 545–551. http://doi.org/10.1080/17445647.2014.923348.</p><p>Tositti L., Cinelli G., Brattich E., Galgaro A., Mostacci D., Mazzoli C., Massironi M., Sassi R., 2017. Assessment of lithogenic radioactivity in the Euganean Hills magmatic district (NE Italy). J. Environ. Radioact. 166, 259–269. https://doi.org/10.1016/j.jenvrad.2016.07.011</p>


Author(s):  
Mohammademad Adelikhah ◽  
Amin Shahrokhi ◽  
Morteza Imani ◽  
Stanislaw Chalupnik ◽  
Tibor Kovács

A comprehensive study was carried out to measure indoor radon/thoron concentrations in 78 dwellings and soil-gas radon in the city of Mashhad, Iran during two seasons, using two common radon monitoring devices (NRPB and RADUET). In the winter, indoor radon concentrations measured between 75 ± 11 to 376 ± 24 Bq·m−3 (mean: 150 ± 19 Bq m−3), whereas indoor thoron concentrations ranged from below the Lower Limit of Detection (LLD) to 166 ± 10 Bq·m−3 (mean: 66 ± 8 Bq m−3), while radon and thoron concentrations in summer fell between 50 ± 11 and 305 ± 24 Bq·m−3 (mean 115 ± 18 Bq m−3) and from below the LLD to 122 ± 10 Bq m−3 (mean 48 ± 6 Bq·m−3), respectively. The annual average effective dose was estimated to be 3.7 ± 0.5 mSv yr−1. The soil-gas radon concentrations fell within the range from 1.07 ± 0.28 to 8.02 ± 0.65 kBq·m−3 (mean 3.07 ± 1.09 kBq·m−3). Finally, indoor radon maps were generated by ArcGIS software over a grid of 1 × 1 km2 using three different interpolation techniques. In grid cells where no data was observed, the arithmetic mean was used to predict a mean indoor radon concentration. Accordingly, inverse distance weighting (IDW) was proven to be more suitable for predicting mean indoor radon concentrations due to the lower mean absolute error (MAE) and root mean square error (RMSE). Meanwhile, the radiation health risk due to the residential exposure to radon and indoor gamma radiation exposure was also assessed.


2013 ◽  
Vol 61 (4) ◽  
pp. 950-957 ◽  
Author(s):  
Abhay Anand Bourai ◽  
Sunita Aswal ◽  
Anoop Dangwal ◽  
Mukesh Rawat ◽  
Mukesh Prasad ◽  
...  

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