NH9.11 | Radioactivity in the environment: opportunities for geosciences and implications for human health
EDI
Radioactivity in the environment: opportunities for geosciences and implications for human health
Co-organized by GI1
Convener: Eleonora BenàECSECS | Co-conveners: Virginia Strati, Alessandra Sciarra, Anita Erőss, Eric PetermannECSECS
Orals
| Thu, 18 Apr, 16:15–18:00 (CEST)
 
Room 0.15
Posters on site
| Attendance Fri, 19 Apr, 10:45–12:30 (CEST) | Display Fri, 19 Apr, 08:30–12:30
 
Hall X4
Posters virtual
| Attendance Fri, 19 Apr, 14:00–15:45 (CEST) | Display Fri, 19 Apr, 08:30–18:00
 
vHall X4
Orals |
Thu, 16:15
Fri, 10:45
Fri, 14:00
Natural radioactivity fully affects our environment as a result of cosmic radiation from space and terrestrial sources from soil and minerals in rocks containing primordial radionuclides as Uranium, Thorium and Potassium. Among the terrestrial sources, Radon (222Rn) gas is considered the major source of ionising radiation exposure to the population and an indoor air pollutant due to its harmful effects on human health (cancerogenic, W.H.O.). Also, artificial radionuclides from nuclear and radiation accidents and incidents provide an additional contribution to the environmental radioactivity.
This session embraces all the aspects and challenges of environmental radioactivity including geological surveys, mineral and space resources exploration, atmosphere tracing including greenhouse gases and pollutant, groundwater contamination, with a specific focus on radon hazard and risk assessment.
Studies about the use of fallout radionuclides as environmental tracers and the relevance of the radioactivity for public health, including the contamination from Naturally Occurring Radioactive Materials (NORM), are welcome.
Contributions on novel methods and instrumentation for environmental radioactivity monitoring including portable detectors, airborne and drones’ surveys and geostatistical methods for radioactivity mapping are also encouraged.

Session assets

Orals: Thu, 18 Apr | Room 0.15

Chairpersons: Eleonora Benà, Virginia Strati, Alessandra Sciarra
16:15–16:20
16:20–16:30
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EGU24-12506
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ECS
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Virtual presentation
Katalin Hegedűs-Csondor, Heinz Surbeck, Petra Baják, and Judit Mádl-Szőnyi

We present an analytical method that allows for the rapid measurement of uranium in water samples. For a 50 ml sample concentrations down to about 2 micro-g/l can be measured within an hour. There are no toxic chemicals used and the whole equipment is portable and can be powered by a 12 V battery. The preparation consists of adding 200 mg silica gel to the 50 ml sample, stirring for 1 hour, filtering out the silica gel and transferring it to a semi-micro cuvette for the measurement. Several samples can be prepared in parallel, depening on the number of magnetic stirrers available. The measurement takes only 1 minute and uses the uranyl fluorescence, enhanced by the adsorption on silica gel. Excitation is done by a pulsed UV-LED at 285 nm. The delayed fluorescence signal around 520 nm is detected by a 6 mm x 6 mm Silicon Photomultiplie (SiPM) behind a 520 nm bandpass filter. Pulsing the LED, converting the SiPM output and displaying the result is controlled by an Arduino microprocessor. All details of the experimental setup as well the software code are presented. It's open source, open to be copied and the whole material costs are only around 500 Euro.

How to cite: Hegedűs-Csondor, K., Surbeck, H., Baják, P., and Mádl-Szőnyi, J.: Rapid field measurement of uranium in water samples , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-12506, https://doi.org/10.5194/egusphere-egu24-12506, 2024.

16:30–16:40
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EGU24-4664
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On-site presentation
Rares Suvaila

Gamma Ray spectroscopy is used in a large number of interdisciplinary applications, providing information on the identity of radioactive nuclides and allows their quantitative determination. 

Gamma Rays are electromagnetic radiations of nuclear origin and their detection is not a direct one, as it depends on the production of secondary particles which can be collected together to produce an electric signal.

Of all detector types, we prefer semiconductor ones, particularly Hyper-Pure Germanium detectors, which have very high efficiencies and excellent energy resolution. Following the sample type, occasionally the computerized analysis of the spectra has to be adapted or customized. The enormous differences between the environmental samples we need to face (from air filters to sediment, water to organic matter) drove us to develop protocols which have a general structure/pattern/methodology, but different approaches when it comes to treat the different matrices, would they be homogenous or not.

The opposite extremes in terms of use of Gamma Ray spectroscopy are the low and high count rate systems. Our job is to evaluate limits, to adapt to the statistical conditions, to calculate correction factors in order to get the results as close as possible to the reality.

Among our strengths there are various non standcard protocols, but also the use of information from the sum (coincident) peaks in order to acknowledge source activity and volume distribution; if the study is based only on the simple gamma peaks, the only information one would get is a large domain of possible positions of the source, without clear activity information. Another important topic is the information on the source homogeneity which is given by the count rates for peaks of different nature.

Our work is mainly experimental; most of the experiments are meant to be performed in the laboratory, as an interdisciplinary approach to nuclear and environmental science. One very important issue to consider in this field is the necessity to adapt to the changing radiation background, no matter the origins of the modifications. Also, the possibility of performing in situ gamma spectrometry is not to be neglected, as it offers multuple benefits, as on the spot analysis, quick tests, feasibility studies, accident dosimetry or simply mapping.

Additionally, we perform neutron activation on the samples, which means we can get the initially non-emitting nuclei to de-excite by gamma radiation: following neutron capture, the activated nuclei disintegrate by a beta process and subsequently emit characteristic gamma radiation, which helps un identify initially "silent" isotopes, bringing precious additional information.

 

Our results obtained experimentally and by Monte Carlo simulations in hypothesis testing of homogeneity properties and/or hot spots in volume sources are now being patented. Also, we seek to develop the quantum correlated gamma spectroscopy field, as it is emerging with new possibilities of treating entangled photons from environmental materials and specimens. Our main purpose for this event is to seek for partnership opportunities accross Europe.

 

How to cite: Suvaila, R.: Gamma spectroscopy for geological studies, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-4664, https://doi.org/10.5194/egusphere-egu24-4664, 2024.

16:40–16:50
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EGU24-19068
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ECS
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On-site presentation
Debora Siqueira Nascimento, Riccardo Ciolini, Andrea Chierici, Stefano Chiappini, Francesco d'Errico, and Massimo Chiappini

The investigation of the dynamics between environmental radioactivity and its implications for human health stands as a fundamental pursuit in contemporary scientific research. Employing the Gamma Spectrometry technique, particularly utilizing High Purity Germanium (HPGe) detectors, emerges as a pivotal methodology to study environmental radioactivity with precision. The veracity and dependability of these analyses hinge upon the scrupulous and precise energy and efficiency calibration of the HPGe system. Within this framework,  we used calibrated IAEA-U and IAEA-Th sources, thereby not only ensuring measurement accuracy but also establishing a robust foundation for comprehensive evaluation of radioactivity levels. Our findings illuminate a comprehensive understanding of the energy and efficiency calibration of the HPGe detector, exemplified by linear relationships in the energy calibration curves for both IAEA-U and IAEA-Th sources, manifesting high correlation coefficients (R² > 0.99). Essential for translating count rates to activity, the efficiency calibration consistently yielded low errors, with the maximum observed efficiency error being less than 4% for both sources, significantly below the recommended by standard rules. This study affirms the reliability and stability of our calibration methods through repeatability assessments over four years. Looking forward, the calibrated HPGe systems are prepared to assume a central role in the spectral analysis of different Italian terrains. Application of these calibrated detectors to Italian soil aims to discern and quantify the presence of radionuclides, thereby contributing into the radioprotection of the region. This prospective dimension underscores the practical application and broader implications of our calibrated systems in addressing environmental and health-related concerns.

How to cite: Siqueira Nascimento, D., Ciolini, R., Chierici, A., Chiappini, S., d'Errico, F., and Chiappini, M.: Long-term Evaluation of HPGe Calibration for Environmental Radioactivity Assessment Using IAEA-U and IAEA-Th Sources, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-19068, https://doi.org/10.5194/egusphere-egu24-19068, 2024.

16:50–17:00
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EGU24-12700
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ECS
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On-site presentation
Arturo Catalá, Ana Navas, and Leticia Gaspar

Understanding the temporal and spatial distribution of soil water content (SWC) is critical for efficient water resource management in agriculture. However, the variability of SWC over time and space presents challenges in obtaining accurate values at field scale using conventional methods. Proximal gamma-ray spectroscopy (PGRS), supported by adequate calibration and biomass corrections, emerge as promising methods for monitoring SWC. The inverse correlation between the gamma counts of the radioisotope 40K (1461 KeV) and volumetric SWC (m3/m3) demonstrates potential for reliable soil moisture estimation in agricultural and hydrological applications. This contribution examines the potential application of a portable sodium iodide (NaI) scintillation detector (PGRS) for estimating SWC in an irrigated wheat field. We explore the sensitivity of the 40K variations to changes in soil moisture and detector height. Over the last two months of the growing season, several one-hour manual monitoring surveys were conducted to capture the effect on 40K signal of irrigation and soil moisture status before and after the harvesting. In each survey, total counts of 40K were recorded using a NaI detector positioned at different elevations above the ground in the middle of a wheat field. Preliminary results indicate a general correlation between 40K (cps) and SWC throughout the study period, suggesting the sensitivity of the PGRS detector to SWC variations. Our findings show a slight increase in 40K counts by decreasing the detector height for all the field surveys conducted. In addition, we observed that the lowest counts of 40K were recorded during the survey with the highest soil water content after irrigation. We can conclude that 40K signal is sensitive to both changes in SWC and the height position of the detector. Furthermore, this detector offers a significant advantage, as it not only captures data on the 40K peak but also analyses the full gamma spectrum.

How to cite: Catalá, A., Navas, A., and Gaspar, L.: Assessing the variability of 40K measurements using a portable gamma-ray spectroscopy in an irrigated agricultural field (Spain), EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-12700, https://doi.org/10.5194/egusphere-egu24-12700, 2024.

17:00–17:10
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EGU24-20104
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Highlight
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On-site presentation
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Caroline Clason, Harriet Davidson, Geoffrey Millward, Andrew Fisher, and Alex Taylor

Glaciers are stores for contaminants, both local and further afield in origin, that are released into the environment through anthropogenic processes. Cryoconite, a heterogenous granular material commonly found on glacier surfaces, is now known to be an efficient accumulator of contaminants such as fallout radionuclides (FRNs) and potentially toxic elements, with multiple regional studies reporting notable concentrations of radioactivity in cryoconite that far exceeds that which is found in other environmental matrices. Indeed, concentrations of FRNs in cryoconite can be as much as three orders of magnitude higher than those found in nearby proglacial sediments. While we now understand that this ‘hyper-accumulation’ of FRNs is commonplace on glaciers around the world, our understanding of the extent to which release of contaminants stored in cryoconite poses an environmental downstream risk is in its infancy. To assess both the activity concentrations and chemical availability of FRNs within cryoconite, we conducted novel sequential chemical extractions twinned with gamma spectrometry for cryoconite samples from glaciers in Arctic Sweden and Iceland. Major and minor elemental composition of cryoconite was also analysed with Wavelength Dispersive X-ray Fluorescence (WD-XRF) spectrometry. The results of these experiments demonstrate that different cryoconite-bound FRNs undergo varying degrees of solubilization, with consequences for increased contaminant mobilization under higher melt scenarios. Our work identifies a clear requirement for further research in this field in order to improve understanding of downstream environmental risk from the secondary release of legacy contaminants under continued glacier retreat.

How to cite: Clason, C., Davidson, H., Millward, G., Fisher, A., and Taylor, A.: Assessing the chemical availability and environmental fate of fallout radionuclides in cryoconite, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-20104, https://doi.org/10.5194/egusphere-egu24-20104, 2024.

17:10–17:20
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EGU24-1450
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ECS
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Highlight
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On-site presentation
Matteo Giordani, Marco Taussi, Maria Assunta Meli, Carla Roselli, Giacomo Zambelli, Ivan Fagiolino, and Michele Mattioli

Recently, high amounts of toxic and radioactive elements have been discovered in epsomite crystals in the abandoned sulphur mine of Perticara, Italy (Giordani et al., 2022). Epsomite represents a neoformed mineral grown in the galleries after the extraction activities of the sulfur mine. In particular, a content of 5.59 ± 0.84 Bq/g of 210Po was detected in the epsomite phase, coupled with other toxic elements such as 228Th, As, Co, Fe, Mn, Ni, Sr, Ti, Zn.

The anomalous content of polonium led to new investigations of the area through the study of different matrices present in the galleries: minerals, host-rock, water, air, dust and bitumen, with the aim to define the origin and the distribution of this hazardous element. The samples were investigated combining several analytical techniques: X-ray Powder Diffraction (XRPD), Environmental Scanning Electron Microscopy (ESEM-EDS), Inductively Coupled Plasma-Atomic Emission (ICP-AES), Inductively Coupled Plasma-Mass Spectrometry (ICP-MS), Atomic Absorption Spectrometry (AAS), Gamma Spectrometry, Alpha Spectrometry, Radon Monitor, and Alpha Track Detector (ATD).

Water samples showed high Al, Fe, Pb, Mg, and Mn content but not radioactive elements. The bitumen sample showed a higher amount of 210Po and 210Pb (0.12 ± 0.02 Bq/g and 0.11 ± 0.02 Bq/g, respectively), compared to the host-rock and fibrous sericolite samples, but lower than fibrous epsomite crystals (210Po 5.59 ± 0.84 Bq/g; 210Pb 5.93 ± 1.19 Bq/g). A slight anomaly in the 40K and 226Ra content of the host-rock was observed (0.38 ± 0.05 Bq/g and 0.052 ± 0.007 Bq/g respectively), and a high 222Rn concentration (up to 2200 ± 300 Bq/m3) was also detected in the tunnels (Giordani et al., 2024).

The confined atmosphere of the mine, with the high 222Rn concentration, is likely the source of the high level of 210Po and 210Pb, in radioactive equilibrium, detected in epsomite. Thus, the 222Rn-rich, anoxic, and hypoxic atmosphere, coupled with the abundance of Mn, Fe, and organic matter in the mine, could play a key role in the 210Po remobilization. This work highlighted that natural epsomite, which is a very common mineral phase in mines, caves, and underground environments, is able to capture 210Po and 210Pb. For this reason, it should be used as a mineral indicator for the presence of radioactive elements in similar environmental conditions, also helping to ensure safe management. These results indicate that in areas with a long history of mining, despite decommissioning, environmental hazards and human health risks may still emerge in terms of radioactivity and potentially toxic elements (PTEs).

 

Giordani, M., Meli, M.A., Roselli, C., Betti, M., Peruzzi, F., Taussi, M., Valentini, L., Fagiolino, I. and Mattioli, M., 2022. Could soluble minerals be hazardous to human health? Evidence from fibrous epsomite. Environmental Research, 206, p.112579.

Giordani, M., Taussi, M., Meli, M.A., Roselli, C., Zambelli, G., Fagiolino, I. and Mattioli, M., 2024. High-levels of toxic elements and radioactivity in an abandoned sulphur mine: Insights on the origin and associated environmental concerns. Science of the Total Environment, 906, p.167498.

How to cite: Giordani, M., Taussi, M., Meli, M. A., Roselli, C., Zambelli, G., Fagiolino, I., and Mattioli, M.: Origin of radioactivity in a neoformed mineral: the case of epsomite from the Perticara sulfur mine, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-1450, https://doi.org/10.5194/egusphere-egu24-1450, 2024.

17:20–17:30
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EGU24-7604
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Highlight
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On-site presentation
Sebastian Baumann, Valeria Gruber, Joachim Gräser, and Dietmar Roth

Radon is a radioactive noble gas. Accumulated indoors it is a large source of radiation exposure. Atmospheric radon can be used as a tracer for greenhouse gases and for atmospheric modelling.

We analyzed long-term (> 10 years) time series of atmospheric radon (Rn-222 and Rn-220) at 15 locations in Austria and neighboring countries. The measured concentrations are equilibrium-equivalent concentrations (EEC), where decay products of radon are measured on air filters with a PIPS-detector. Other parameters as ambient dose rate and weather data (wind, rainfall and precipitation) are measured at the same location. Additional for one year the atmospheric radon concentration was measured directly with a different measurement system (Alphaguard) at three locations.

The analysis of the EEC showed that the temporal variation of atmospheric radon (Rn-222, Rn-220) depends on meteorological parameters. Seasonal and diurnal variations are linked to the stability of atmospheric layers. Under stable weather conditions higher radon concentrations occur. Correlation of the radon concentrations were found primarily with temperature and wind speed. At temperatures below 0 °C, Rn-220 shows very low concentrations and a different behavior than Rn-222. This reduction of Rn-220 availability could be associated with frozen or snow-covered soils.

The additional measurements (Alphaguard) of atmospheric radon concentrations provided plausible long-term averages, although individual measurements can provide implausible values (e.g. negative values). The temporal patterns of the two measurement systems are very similar, and the atmospheric radon concentrations are predominantly higher than the EEC.

A connection of the long-term average values of the atmospheric radon and the radon potential of an area was found, by comparing atmospheric radon concentrations with indoor radon measurements and predictions of the radon potential in Austria. This indicates that the radon potential determines the average level of the atmospheric radon concentrations and weather conditions temporally modulate the atmospheric radon concentrations around this level.

This work is supported by the federal ministry of Austria for climate action and the project RadoNORM, which has received funding from the Euratom research and training programme 2019-2020 under grant agreement No 900009.

How to cite: Baumann, S., Gruber, V., Gräser, J., and Roth, D.: Long-term atmospheric radon measurements and their connection with environmental conditions, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-7604, https://doi.org/10.5194/egusphere-egu24-7604, 2024.

17:30–17:40
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EGU24-21822
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On-site presentation
Rouwen Lehne, Jessica Daum, Johannes Mair, Heiner Heggemann, Christian Hoselmann, and Andreas Henk

Radon soil air measurements and associated permeability measurements are a mandatory prerequisite for the calculation of radon potentials as an important basis for the statistical derivation of an expected radon situation in a defined area. Accordingly, in the federal state of Hesse, as almost everywhere in Germany, numerous measurements have been carried out in recent years and made available to the Federal Office for Radiation Protection (BfS) for the modelling of a radon potential map of Germany, which has since been an important (sometimes the only) basis for the definition of radon precautionary areas for all federal states in Germany. The associated benefits are undoubtedly great.

From a geological perspective, however, the question arises to what extent the large lateral variability of measurable radon concentrations also exists in the vertical and, if so, whether this variability can be placed in a context with the geological development of the area under consideration. The background to this is the fact that the radon soil gas measurements usually address a depth of between 0.8 and 1 m below the ground surface, in rare cases reaching a depth of up to 2 metres.

In addition to the scientific added value, such an investigation approach is also associated with an applied benefit, as building foundations are usually founded significantly deeper than 1 m below the ground surface, which means that a significant part of the building envelope in contact not only with the soil layers, but also to the geological subsurface, must be seen decoupled from the radon concentration determined near the surface, depending on the heterogeneity of the geological bedding.

For this reason, we took a total of 175 samples along an 323 m deep research drilling in the northern Upper Rhine Graben and determined the radon concentration for these in the laboratory (= stationary). The results show a very high variability of the measurable radon concentrations, ranging from 16 Bq/m³ to 9086 Bq/m³ with a mean value of approx. 1527 Bq/m³. At the same time, the radon concentrations determined show a very good correlation with both the geological response of the drill core and the gamma log measurements carried out.

In this presentation, we would like to show the results obtained so far and look at the possibility of regionalising the measured values as well as the next work steps.

How to cite: Lehne, R., Daum, J., Mair, J., Heggemann, H., Hoselmann, C., and Henk, A.: Observation and geological interpretation of the longest vertical radon profile to date: variability of radon concentrations along a 323 m deep drilling, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-21822, https://doi.org/10.5194/egusphere-egu24-21822, 2024.

17:40–17:50
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EGU24-18058
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ECS
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On-site presentation
Tóth Szabolcs, Horváth Ákos, and Sajó-Bohus László

Field uranium research began in Hungary in 1947 under the guidance of Hungarian specialists. After the research period, mining plants were opened one after the other, and an ore processing plant was also established. The ore grade found in the Mecsek Mountains was less favorable than average, 1 ton of ore contained 1.2 kg of uranium metal. The characteristic of the uranium ore found in the permian sandstones is that it occurs in several layers and levels, not continuously, but in lenticular spots with varied development. This geological occurence significantly increased the costs. By 1989, Hungarian uranium ore mining had become uneconomical, and a government decision was made to close it down, dating back to 1997. The recultivation process began in 1998. Currently, environmental damage is being eliminated under the title of long-term monitoring. Due to the proximity of inhabited areas, NORM anomalies, and the presence of radon gas, radiation protection played a particularly important role during and after remediation.

The radon monitoring of the abandoned mine cavity system was carried out with active radon monitors placed in different boreholes, closed shafts and adits. In the last two years, a radon soil gas monitoring station has also been operated on a waste rock pile site covered with 1 m of loess cover to check the radon retention capacity of the soil.

For radon detection alpha-sensitive photodiode (sensitive area: 1 cm2) or PIPS detector (sensitive area: 3 cm2) are used. The Dataqua monitoring system gives one impulse per hour for 140 and 56 Bq/m3222Rn concentration, respectively, for the photodiode and PIPS detector. The multi-channel devices beside the radon detector can include other additional sensors for temperature, pressure, humidity, water level, salinity, etc. measurements to study the relation between the variation of radon concentration and other environmental parameters. The radon concentration together with other environmental parameters are continuously recorded with one measurement per hour sampling frequency for several years.

In closed, underground places extremely high radon concentration (a couple of tens up to hundred kBq/m3, may occur in the absence of ventilation, even in rocks of average radionuclide content. According to our measurements both the daily and the yearly variation is well recognizable, which originate from the variation of the meteorological and lunisolar parameters. In the case of a few time series, we revealed a strong correlation between the outside temperature and the resulting radon concentrations.  We found the atmospheric pressure also affects radon levels, but extent and only on a smaller scale than temperature. 

Comprehensive statistics and Fourier analysis were also carried out in order to examine the dominant frequencies, and we also examined the change of the one day long components as a function of time.

How to cite: Szabolcs, T., Ákos, H., and László, S.-B.: Studies on radon time series in various underground environments: Case of abandoned Kővágószőlős uranium mine, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-18058, https://doi.org/10.5194/egusphere-egu24-18058, 2024.

17:50–18:00
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EGU24-6182
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On-site presentation
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Peter Bossew and Nivaldo Da Silva

Brazil is envisaging a large scale plan for indoor radon assessment. Radon levels shall be mapped and priority areas identified. Given the size of the country and its diversity in natural and socio-economical respects, this is a challenging project. Pilot studies and local surveys have been performed in the past but no country-wide assessment exists.

In November 2023, the IAEA organized a workshop on radon survey planning in Poços de Caldas, Minas Gerais, Brazil, to support the project. The objective was to identify items which have to be resolved before starting the actual experimental, i.e., field and laboratory work; so to speak, asking the right questions beforehand to render work as efficiently as possible. Experts from several scientific disciplines related to radon participated (physics, statistics, geology, geography, radiology, national demographic database management, etc.). Among the questions which result from experiences with past surveys, are:

  • Which is the objective of the survey? (Assessment of radon hazard, of collective risk, of detriment attributable to radon, decision base for mitigation action, etc.)
  • Which is the target quantity? (Mean concentration in living rooms over an area, probability to exceed a reference level within an area, status of an area as priority area, etc.)
  • Which is the mapping support, i.e., the geographical area to which a value of the target quantity shall be assigned? (Municipality, administrative region, geological unit, grid cell, etc.)
  • Which spatial estimation strategy is chosen: design based (inference only from radon measurements) or model based (inference from predictor quantities such as geology or ambient dose rate)?
  • How to generate a representative sampling scheme, and how to verify it?
  • In case of a design based strategy: which sample size is required to achieve a given accuracy of the result? More generally: which information is necessary to establish an uncertainty budget of the target quantity?
  • How should an operational database be structured, which metadata should be included?
  • How should a "cooking recipe" look like, which generation of new data should follow? ("Bottom-up harmonization") How can existing data be integrated into the database ("Top-down harmonisation")?
  • How can experiences gained during pilot and local projects be transferred and "upscaled" to different environments and larger regions?
  • How should a QA/QC scheme look like, appropriate to the project?

These questions, some of which are by no means trivial, should be thoroughly discussed and answered before actually starting a survey. Some of them will be addressed in the presentation.

 

How to cite: Bossew, P. and Da Silva, N.: Designing an indoor radon survey - results of a recent IAEA workshop on survey planning in Brazil, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-6182, https://doi.org/10.5194/egusphere-egu24-6182, 2024.

Posters on site: Fri, 19 Apr, 10:45–12:30 | Hall X4

Display time: Fri, 19 Apr, 08:30–Fri, 19 Apr, 12:30
Chairpersons: Anita Erőss, Alessandra Sciarra, Eric Petermann
X4.126
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EGU24-888
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ECS
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Highlight
Saeed Bidar Kahnamuei, Katalin Hegedűs-Csondor, Petra Baják, Ákos Horváth, Dénes Szieberth, György Czuppon, Márta Vargha, Bálint Izsák, and Anita Erőss

One of the largest natural thermal lakes in the world, Lake Hévíz is located in the southwestern part of the Transdanubian Range’s karst system (Hungary). It is fed by springs with different temperatures, which are located in a cave beneath the lake. The mixing of cold and hot waters generates the lake’s sulphuric therapeutic water, and it is responsible for the cave formation at the bottom, resulting in the lake's unique ecosystem. The presented research aimed at the comprehensive geochemical characterization of waters in the wider surroundings of the lake (lake water, springs, observation, drinking water, and thermal water wells). Investigating the geochemical characteristics of water took on a novel perspective through the innovative application of radionuclides as natural tracers. Within the framework of this investigation, we utilized uranium, radium, and radon isotopes to identify the mixing of fluids and infer the mixing end members in the Hévíz karst system. Alpha spectrometry was applied on selectively adsorbing Nucfilm discs as an inventive approach to measure uranium and radium isotopes. Moreover, stable isotopic ratios of hydrogen and oxygen (δ2H and δ18O) were determined to supplement the information on waters with different origins. Hydrochemical water analysis for measuring the concentration of major ions and trace elements was carried out using ICP-MS, ion chromatography, and UV-Vis spectrophotometry. The inferred fluid end members and their compositions are anticipated to provide insightful information on the hydrogeological functioning of the Lake Hévíz karst system, which is indispensable in sustainable water resource management and understanding climate change's impact.

 

 

Keywords: Thermal lake; Hydrogeochemical characteristics; Mixing fluids; Radionuclides; Stable isotopes; ICP-MS, Nucfilm, Alpha spectroscopy

How to cite: Bidar Kahnamuei, S., Hegedűs-Csondor, K., Baják, P., Horváth, Á., Szieberth, D., Czuppon, G., Vargha, M., Izsák, B., and Erőss, A.: Identifying Mixing Components by Natural Tracers in the Lake Hévíz System, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-888, https://doi.org/10.5194/egusphere-egu24-888, 2024.

X4.127
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EGU24-908
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ECS
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Highlight
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Michele Franceschi, Matteo Alberi, Marco Antoni, Ada Baldi, Alessio Barbagli, Luisa Beltramone, Laura Carnevali, Alessandro Castellano, Giovanni Collodi, Enrico Chiarelli, Tommaso Colonna, Vivien De Lucia, Andrea Ermini, Andrea Maino, Fabio Gallorini, Enrico Guastaldi, Nicola Lopane, Antonio Manes, Fabio Mantovani, Samuele Messeri, Dario Petrone, Silvio Pierini, Kassandra Giulia Cristina Raptis, Andrea Rindinella, Riccardo Salvini, Daniele Silvestri, Virginia Strati, and Gerti Xhixha

Soil Water Content (SWC) is a key information in precision agriculture for obtaining high levels of efficiency and health of crops, while reducing water consumption. In particular, for the case of vineyards, due to the recent extreme temperature fluctuations, the knowledge of the SWC of the entire field becomes crucial to allow a timely intervention with emergency irrigation to preserve plant health and yield.

Unlike electromagnetic SWC measurements, that are punctual and gravimetric measurements, that are punctual and also time-consuming, the Proximal Gamma Ray Spectroscopy (PGRS) technique can provide field-scale, non-invasive, and real-time measurements of SWC. This is achievable through an in-situ NaI detector, continuously recording photons resulting from the radioactive decay of 40K in the soil, which are attenuated proportionally based on the amount of stored water. Given the inverse proportionality between soil moisture and photons detected by the gamma ray sensor, the SWC value can be easily obtained.

In this study we investigate the performance of PGRS applied to the case of study of a vineyard at the farm “Il Poggione” located in Montalcino (Siena, Italy).

The effectiveness of the results obtained is supported by different tests: first the validation allowed to compare the PGRS measurement (5.8 ± 1.5)% with a gravimetric measurement (9.0 ± 2.5)%, highlighting a 1-σ agreement; then by the rainfall recognition capability indeed, in correspondence to the most significant rainfall event (18 mm) the SWC value before and after the rain increased of 7.8%.

Moreover, the integration of the in-situ system with an agrometeorological station resulted in a Web App, allowing for real time data storage and thus facilitating data management, spectrum analysis, and display for both gamma ray sensor and agrometeorological station results, enabling comprehensive studies of environmental parameters (e.g., temperature, air humidity).

This research underlines the potential of PGRS as a precise, real-time, and field scale SWC monitoring tool not only in vineyards but for cultivated fields in general. Further refinements concerning the gamma ray spectra analysis and broader applications in environmental monitoring are envisaged for improved agricultural practices.

This study was supported by the project STELLA (Sistema inTEgrato per Lo studio del contenuto d'acqua in agricoLturA) (CUP: D94E20002180009) funded by the Tuscany region under the program POR FESR 2014/2020.

How to cite: Franceschi, M., Alberi, M., Antoni, M., Baldi, A., Barbagli, A., Beltramone, L., Carnevali, L., Castellano, A., Collodi, G., Chiarelli, E., Colonna, T., De Lucia, V., Ermini, A., Maino, A., Gallorini, F., Guastaldi, E., Lopane, N., Manes, A., Mantovani, F., Messeri, S., Petrone, D., Pierini, S., Raptis, K. G. C., Rindinella, A., Salvini, R., Silvestri, D., Strati, V., and Xhixha, G.: Proximal Gamma Ray Spectroscopy for monitoring Soil Water Content in vineyards, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-908, https://doi.org/10.5194/egusphere-egu24-908, 2024.

X4.128
|
EGU24-12663
|
ECS
Petra Baják, Daniele Pedretti, András Csepregi, Muhammad Muniruzzaman, Katalin Hegedűs-Csondor, and Anita Erőss

In Hungary, the drinking water supply relies upon groundwater resources of up to 98%. As a drinking water resource, groundwater must meet strict quality requirements in order to minimise any health effects arising from daily water consumption. Water-rock interactions enrich groundwater not only with essential elements (e.g. Ca, Mg) but also with undesired substances such as heavy metals or radioactive elements. In the last few years, a thorough drinking water quality monitoring campaign was carried out in Hungary, revealing that some parts of the country are characterised by relatively high uranium concentrations. The causes of these elevated activities have not been properly investigated, yet. However, understanding the controls of the release and mobility of uranium is critical in proper groundwater management.

Baják et al (2022) developed a one-dimensional (1-D) geochemical model using the code PHREEQC (Parkhurst and Appelo, 2013) to examine the processes that determine the fate of uranium in the siliciclastic Miocene-Quaternary aquifer system near Velence Hills, some 50 km off Budapest. Here, the geological build-up (granitic rocks on the surface) favours the high uranium content in groundwater, which is characterised by oxidising conditions. The 1-D model included redox-controlled kinetic reactions as well as other potential uranium-controlling processes (e.g., surface complexation). The results suggested that uranium distribution is sensitive to redox changes in the aquifer and its mobility in groundwater especially depends on the residence time of water compared to the reaction times controlling the consumption of oxidising species.

This study introduces a two-dimensional multicomponent reactive transport model developed using the PHT3D code (Prommer et al., 2003), which is a coupling between MODFLOW and PHREEQC. The model builds on and extends the capability of the 1-D model to simulate uranium mobility across the multiple flow paths of the aquifer systems. The model calibration accounts for 30 groundwater samples collected from drinking water wells in the study area. Physico-chemical parameters (temperature, pH, specific electric conductivity, redox potential) were measured on-site, and the samples were analysed for natural tracers (δ16O, δ2H, 234U, 238U, 226Ra) to gain further insight into the geochemical processes of the aquifer system.

This research was supported by the ÚNKP-23-4 New National Excellence Program of the Ministry for Culture and Innovation from the source of the National Research, Development and Innovation Fund and was supported by the János Bolyai Research Scholarship of the Hungarian Academy of Sciences. The research is part of a project which was funded by the National Multidisciplinary Laboratory for Climate Change, RRF-2.3.1-21-2022-00014.

References:

Baják, P., Csondor, K., Pedretti, D., Muniruzzaman, M., Surbeck, H., Izsák, B., Vargha, M., Horváth, Á., Pándics, T., Erőss, A., 2022. Refining the conceptual model for radionuclide mobility in groundwater in the vicinity of a Hungarian granitic complex using geochemical modeling. Applied Geochemistry 137, 105201.

Parkhurst, D.L., Appelo, C.A.J., 2013. Description of Input and Examples for PHREEQC Version 3—A Computer Program for Speciation, Batch-Reaction, One-Dimensional Transport, and Inverse Geochemical Calculations. (USGS Technical No. 6(A)43). U.S. Geological Survey, Denver, CO, USA.

Prommer H, Barry, D.A., Zheng, C. (2003). MODFLOW/MT3DMS based reactive multi-component transport modeling. Ground Water, 41(2).

How to cite: Baják, P., Pedretti, D., Csepregi, A., Muniruzzaman, M., Hegedűs-Csondor, K., and Erőss, A.: Preliminary results of two-dimensional multicomponent reactive transport modelling to understand the controlling factors on uranium mobility in a siliciclastic aquifer in Hungary, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-12663, https://doi.org/10.5194/egusphere-egu24-12663, 2024.

X4.129
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EGU24-5787
|
ECS
Eleonora Benà, Giancarlo Ciotoli, Peter Bossew, Eric Petermann, Luca Verdi, Claudio Mazzoli, and Raffaele Sassi

Radon (222Rn) is a radioactive gas considered the major source of ionizing radiation exposure for the population and represents a significant health risk when it accumulates indoor environments. In Europe the regulation has been implemented in order to address the issue of indoor radon exposure, including pose national reference levels and the identification of the so-called Radon Priority Areas (RPAs). Although the European directive states that RPAs are defined as those areas where the annual average Indoor Radon Concentrations in a significant number of dwellings is expected to exceed the reference level the concept and interpretation of “significant number of buildings” in the European Directive remained unclear. According to this idea, radon is classified as an anthropogenic hazard since it has a strong correlation with IRC. However, indoor radon levels can vary significantly at the municipal level also among neighbouring dwellings, mostly due to differences in building characteristics and inhabitants’ habits. Since in this way the radon natural origin may be bypassed, many authors (mostly geologists) propose to use the Geogenic Radon Potential (GRP) as a hazard indicator. The GRP represents the amount of radon that can potentially influx within buildings from geogenic sources. Being the radon hazard and risk concepts still debated, in the last year, researchers proposed a clear transition from the radon hazard to the more comprehensive radon risk concept proposing that mapping this geo-hazard (GRP) is a fundamental step to define the collective radon risk exposure. The Collective Risk Areas (CRAs) are composed by many possible little Individual Risk Areas (IRAs). Considering that the radiation protection aimed to reduce the detriment, radon abatement policies have to take care of these CRAs not forgetting areas with high individual risk in order to protect individuals from high exposure. On the one hand the collective risk areas have proposed as geological-based risk areas; on the other hand, the individual risk areas are strictly linked to the Indoor Radon Concentration (IRC) and may be assimilated to the “classical” RPAs concept. Considering the absence of an unambiguous methodology at the European scale to define the RPAs and the proposed CRAs mapping as the first step to define the IRAs (“classical” RPA), with this work we aimed to lay the foundation to create a definitive methodology for the individual risk-based RAPs mapping considering, first of all, the number of people involved. The test area chosen for this study is the Bolzano province (Italy) due to the high availability of potential predictors variables and a detailed IRC survey campaign on the entire provincial territory. Starting from this we proposed the first IRAs map (i.e., the first individual risk-based RPAs definition) using a set of Machine Learning techniques allowing to connect and validate the geo-hazard with real IRC measured in the province, with the aim to predict both the collective risk and the possible individual detriment as required by the European regulation.

How to cite: Benà, E., Ciotoli, G., Bossew, P., Petermann, E., Verdi, L., Mazzoli, C., and Sassi, R.: From the collective to the individual radon risk exposure: an insight in the current European regulation, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-5787, https://doi.org/10.5194/egusphere-egu24-5787, 2024.

X4.130
|
EGU24-19881
gaia soldati, maria grazia ciaccio, antonio piersanti, Valentina cannelli, and gianfranco galli

The urbanized area of Rome is largely built over volcanic deposits, characterized by  a significant radionuclides content and radon emanation potential.  A first step towards the mitigation of the indoor radon exposure is the accurate monitoring of workplaces and residential dwellings. Due to the complex interactions among many environmental parameters on different time scales, a proper assessment of radon diffusion dynamics and concentration variations can be better achieved by means of active monitoring approaches. We present here the results of one year of continuous measurements conducted in 6 premises (5 apartments and a basement) at different floors of the same building in the Esquilino district, in the historical center of Rome. The simultaneous tracking of different floors should cancel the influence of geogenic radon and of building characteristics like age, typology, and construction materials, and reveal the characteristics of the gas emanation and transport inside the buildings, and of its temporal fluctuations, with the final goal to select the most suitable preventive measures to reduce radon exposure. Conducting the experiment in the Roman urban contest, we cannot ignore the specificity of the retrieved data, affected not only by endogenous factors like heating and ventilation of the apartments, but also by exogenous factors like the urban heat islands effect.

How to cite: soldati, G., ciaccio, M. G., piersanti, A., cannelli, V., and galli, G.: Multi-level continuous monitoring of residential radon in the urban contest of Rome, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-19881, https://doi.org/10.5194/egusphere-egu24-19881, 2024.

X4.131
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EGU24-8408
|
ECS
Martín Dominguez Duran, María Angélica Sandoval Garzón, and Carme Huguet

Radon (222Rn) is a naturally occurring gas that represents a health threat due to its causal relationship with lung cancer. Despite its potential health impacts, several regions have not conducted studies, mainly due to data scarcity and/or economic constraints. This study aims to bridge the baseline information gap by building an interactive dashboard that uses inferential statistical methods to estimate indoor radon concentration’s (IRC) spatial distribution for a target area. We demonstrate the functionality of the dashboard by modelling IRC in the city of Bogotá, Colombia, using 30 in situ measurements. IRC measured were the highest reported in the country, with a geometric mean of 91 ±14 Bq/m3 and a maximum concentration of 407 Bq/m3. In 57 % of the residences RC exceeded the WHO's recommendation of 100 Bq/m3. A prediction map for houses registered in Bogotá’s cadastre was built in the dashboard by using a log-linear regression model fitted with the in-situ measurements, together with meteorological, geologic, and building specific variables. The model showed a cross-validation Root Mean Squared Error of 56.5 Bq/m3. Furthermore, the model showed that the age of the house presented a statistically significant positive association with RC. According to the model, IRC measured in houses built before 1980 present a statistically significant increase of 72 % compared to those built after 1980 (p-value = 0.045). The prediction map exhibited higher IRC in older buildings most likely related to cracks in the structure that could enhance gas migration in older houses. This study highlights the importance of expanding 222Rn studies in countries with a lack of baseline values and provides a cost-effective alternative that could help deal with the scarcity of IRC data and get a better understanding of place-specific variables that affect IRC spatial distribution.

How to cite: Dominguez Duran, M., Sandoval Garzón, M. A., and Huguet, C.: Indoor 222-Rn Modeling in Data-Scarce Regions: An Interactive Dashboard Approach for Bogotá, Colombia, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-8408, https://doi.org/10.5194/egusphere-egu24-8408, 2024.

X4.132
|
EGU24-19738
Radon measurements in work environments for underground water extraction in an area of central-north Italy with low potential risk: a concrete case of passive/active measurements in the workplace and active measurements in water by LSC.
(withdrawn after no-show)
Mattia Taroni, Andrea Iannarone, and Giacomo Zambelli
X4.133
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EGU24-16925
|
ECS
Johannes Mair, Eric Petermann, Rouwen Lehné, and Andreas Henk

This study, conducted about 30km south of Frankfurt in the Northern Upper Rhine Graben, focuses on deepening the understanding of Radon concentrations in soil air. The selected area, where neotectonic activity was proven in an accompanying project, provides an ideal setting for investigating Radon variability, particularly its potential correlation with fault zones in unconsolidated rocks or sedimentary basins. Understanding the factors influencing Radon levels in the environment is a complex task, as they are affected by a multitude of variables. Our work aims to decipher these influences and, if possible, quantitatively analyse the contributions of each variable. By doing so, we hope to gain a clearer understanding of how different environmental factors interact to determine Radon levels.

A central element of our research is the use of Random Forest models, chosen to handle our multidimensional dataset. This dataset includes a variety of parameters such as Radon measurements, nuclide content, soil grain sizes, weather data, and the distance to fault zones. Random Forest models are particularly effective for this type of complex data because they can analyse many different factors at once and uncover hidden patterns.

Contrary to initial hypotheses, our findings indicate that in unconsolidated rocks and sedimentary basins, the grain size of soil is the most influential factor in determining soil air Radon levels, closely followed by soil moisture. These results challenge the previously held belief that fault zones are the primary influencing factors on Radon concentrations in these geological settings.

How to cite: Mair, J., Petermann, E., Lehné, R., and Henk, A.: Deciphering Radon Variability in the Northern Upper Rhine Graben: An Analysis Using Passive and Active Detection with Random Forest Modelling, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-16925, https://doi.org/10.5194/egusphere-egu24-16925, 2024.

X4.134
|
EGU24-17300
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ECS
|
Highlight
Adam Howes, Dafina Kikaj, Edward Chung, Ute Karstens, Alistair Manning, Stephan Henne, Angelina Wenger, Grant Foster, Simon O'Doherty, Chris Rennick, and Tim Arnold

Given its unique properties as a radioactive chemically inert gas, radon can act as a valuable atmospheric tracer, for evaluating the performance of atmospheric transport models to calculate the sources of trace gases to the atmosphere. A radon flux map is the scientific starting point for simulating atmospheric radon concentrations using atmospheric transport models. As such, it is important to assess the available high resolution radon flux maps to ensure that simulated concentrations can be accurately interpreted. The spatial fluxes of radon primarily depend on soil and rock types, while temporal variations are influenced by soil moisture content.

The recent advancements in generating two high-resolution radon flux maps for Europe using two different soil moisture reanalysis, GLDAS Noah and the ERA5 maps1, have significantly enhanced our understanding of radon flux dynamics. Yet, the radon flux values diverge notably between these two maps and sometimes these variations can be substantial, with differences as large as the absolute radon flux itself.

In our work, two available versions of European radon flux maps are coupled with two Lagranian particle dispersion models – the Met Office’s Numerical Atmospheric Modelling Environment (NAME) and the FLEXPART model – are used to simulate radon concentrations measured at four tall tower sites in the United Kingdom: Heathfield, Ridge Hill, Tacolneston and Weybourne. We calculate the differences between the modelled radon concentrations to the observed radon concentrations at these sites and use this to investigate the sensitivity of two radon flux maps: GLDAS Noah and ERA5.

 

References: 12022: https://doi.org/10.18160/2ST9-3NAD

How to cite: Howes, A., Kikaj, D., Chung, E., Karstens, U., Manning, A., Henne, S., Wenger, A., Foster, G., O'Doherty, S., Rennick, C., and Arnold, T.: Investigating the sensitivity of flux maps in simulating radon concentrations at greenhouse gas monitoring sites, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-17300, https://doi.org/10.5194/egusphere-egu24-17300, 2024.

X4.135
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EGU24-17369
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Highlight
Alessandra Sciarra, Luca Pizzino, Gianfranco Galli, Daniele Cinti, Giancarlo Ciotoli, and Sabina Bigi

Ciampino area has been the subject, from 1999 onwards, to reiterated geochemical surveys on soil-gas, spring waters and groundwater, commissioned by the municipality to INGV (National Institute of Geophysics and Volcanology). Indeed, this area is affected by huge CO2 emissions of volcanic origin and high levels of indoor radon. Both gases can constitute a big concern for local population known as Natural Gas Hazard (NGH). Accordingly, the distribution of the two gases in groundwater, soils and indoor buildings must be assessed in order to define sectors of the territory more exposed to NGH.
Interest in the Natural Gas Hazard arose mainly starting from November 1995, when several homes, basements and wells were affected by widespread exhalations, to the point of danger to human health.
The most area affected is characterized by abundant and concentrated gas leaks which caused the death of 29 cattle and some sheep in September 1999 and March 2000, until December 2000 when a paroxysmal episode caused the death of a man.
The main activities carried out in the last 25 years have concerned:
-    sampling of water sites (about 100 natural springs, public and private wells), measuring chemical-physical parameters, CO2 and 222Rn contents;
-    monthly indoor radon measurements (around 500/year) in 14 selected sites (both private homes and workplaces, including schools);
-    measurements of radon in soils (about 300) to identify the areas with the greatest degassing and the possible relationship with existing tectonic structures;
-    continuous indoor radon measurements in a selected home;
-    spot measurements in groundwater and intervention in the event of reports from the municipality and/or private citizens of emergency situations resulting from gaseous emanations falling in areas of the municipal territory of Ciampino.
The data obtained include measurements of flux and concentration of soil gases, distribution of pCO2 and radon in groundwater, radionuclide content in soils from different geological units, indoor radon measurements.
All this data has allowed us to define the sectors at greatest risk, by identification and delimitation of NGH risk areas. Dissemination and information activities on the NGH were carried out through public meetings, seminars and the drafting of brochures. Also training activities for the staff of the Civil Protection and Environment Offices of the Municipality were performed.
The experience gained has allowed the participation of INGV in a European project Life Respire for the monitoring and remediation of the radon problem.
Based on the distribution of the different samples collected: soil gas, terrestrial gamma dose rate and rock/soil samples by radionuclide content, we were able to provide the local authorities the map of the geogenic potential of radon for the whole municipal territory.

How to cite: Sciarra, A., Pizzino, L., Galli, G., Cinti, D., Ciotoli, G., and Bigi, S.: INGV experience on radon monitoring in the Ciampino Municipality (Rome, Italy): a link between research and territory, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-17369, https://doi.org/10.5194/egusphere-egu24-17369, 2024.

X4.136
|
EGU24-3352
Dagmara Tchorz-Trzeciakiewicz

The research aimed to analyse variations in soil gas radon concentrations and geogenic radon potential in areas of typical building plots located in regions known for high and low geogenic radon potential. The study was designated to address the following questions:

  • Are spatial variations in soil gas radon concentrations and radon potential statistically important in the area of a typical building plot? Are these variations similar in regions known for high and low radon potential?
  • How many measurement points should be proposed to properly evaluate geogenic radon potential and radon index on the building plot area?
  • Can an in-situ gamma spectrometric survey, combined with soil properties, be useful in the defining radon index at the area of the building plot?
  • Are seasonal variations of soil gas radon concentration significant at a depth of 0.8 m?  If so, which season is the most appropriate to evaluate geogenic radon potential?

The research was conducted in two counties: Wrocław and Dzierżoniów located in the Lower Silesian Voivodeship in the southwest part of Poland. Dzierżoniów County is among the counties listed in the Regulation of 18 June 2020 of the Minister of Health where the average radon concentration in a significant number of buildings may exceed the reference level of 300 Bq m−3. In both regions, three building plots, each of an area of 300 m2 (which is the size of a typical building plot in an urban area in Poland) were identified. At each building plot, five measurement points were designated -  at the four corners and in the middle of each plot. The research at each measurement point included the following procedures:

  • Soil gas radon concentration measurements at the depth of 0.8 m using solid nuclear track detectors have been performed. The detectors were replaced at the beginning of each season starting from summer 2023.
  • The radionuclides contents in the soil were measured in situ using the gamma-ray spectrometer Exploranium RS-230.
  • The ambient gamma dose rate was measured by the radiometer RK-100
  • Various soil properties including grain size, permeability, and filtration coefficient were determined.

Additionally, at each building plot, the instantaneous radon concentration and soil permeability measurements were performed using Lucas cells and RADON-JOK.

The preliminary research results indicate that in Dzierżoniów County uranium contents were in the range from 1.6 ppm to 3.3 ppm and thorium from 5.4 ppm to 8.2 ppm, whereas in Wrocław County uranium contents were in the range from 1.6 ppm to 2.5 ppm and thorium from 4.3 ppm to 7.4 ppm. The instantaneous survey of radon concentration revealed that in Dzierżoniów County soil gas radon concentration varied from 10.338 kBq m-3 to 31,050 kBq m-3 and soil permeability from 1*10-12 m2 to 1*10 -13 m2, whereas in Wrocław county the soil radon concentration varied from 0.102 to 0.266 kBq m-3 and soil permeability form very low (impossible to measure by used equipment) to 2*10-13m2.

Research project supported by program „Excellence initiative – research university” for years 2020-2026 for University of Wrocław

How to cite: Tchorz-Trzeciakiewicz, D.: Variations of soil gas radon concentrations in a typical building plot area - preliminary results, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-3352, https://doi.org/10.5194/egusphere-egu24-3352, 2024.

X4.137
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EGU24-9434
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ECS
Linda Bonorino, Gianluca Beccaris, Paola Bisi, Paolo Chiozzi, Andrea Cogorno, Elga Filippi, Riccardo Narizzano, Sonja Prandi, and Massimo Verdoya

Radon (222Rn) is one of the most common naturally occurring radioactive elements and is particularly interesting to environmental issues, for it is considered a carcinogenic gas. It is a decay product of 238U, contained in most rocks and soils, and can easily escape from the ground to accumulate in closed spaces where it may become dangerous. The knowledge of its potential is vital to urban development plans and to protect people from potential hazards. We recently conducted monitoring campaigns in Liguria (NW Italy) to investigate the relations between the observed indoor radon concentrations and the geo-lithological background. We focused on the geological units of the Western Alps, characterized by various lithotypes, ranging from sedimentary to metasedimentary and metavolcanic rocks. The natural gamma radiation was measured on outcrops. Spectrometric measurements indicated that metamorphic acid rocks have the highest specific activity values of 238U (75-85 Bq/kg). In metasedimentary rocks, quartz and mica schists show the highest concentration of 238U, with an average specific activity of 56 Bq/kg. Sedimentary rock types are characterized by average specific activities < 40 Bq/kg., The dosimetric indoor surveys highlighted that about 40% of the investigated public and private buildings show indoor radon values above 200 Bq/m3. These preliminary campaigns revealed a relationship between the uranium content of the bedrock and the indoor radon. The correlation can be used to predict the geogenic radon potential based on a geological background when dosimetric data are few or scattered. In this paper, we refined our early analysis by integrating the dataset with further spectrometric and indoor dosimetric records, which were also coupled with soil radon measurements. The radon concentration in soil was investigated focusing on the sites where the previous monitoring campaigns showed high indoor radon concentrations. Soil radon was recorded at depths between 50 and 80 cm, where radon diffusion from the ground to the buildings very likely occurs. Soil radon concentrations substantially agree with spectrometric measurements. The largest concentration of 222Rn was found in the soils on more acid metamorphic rocks (porphyroid and porphyric shists) with values of about 100 kBq/m3. The lowest values about (20 kBq/m3) were recorded in soils occurring in sedimentary rocks. Despite the limitations and uncertainties, mainly related to the uneven data coverage and the complex interaction between the building and the bedrock, the combined techniques can identify areas of potentially high indoor radon concentrations.

How to cite: Bonorino, L., Beccaris, G., Bisi, P., Chiozzi, P., Cogorno, A., Filippi, E., Narizzano, R., Prandi, S., and Verdoya, M.: A combined approach for the correlation between indoor radon and geological background: application in the western Ligurian Alps (Italy), EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-9434, https://doi.org/10.5194/egusphere-egu24-9434, 2024.

X4.138
|
EGU24-12397
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ECS
Diana Altendorf, Henning Wienkenjohann, Florian Berger, Jörg Dehnert, Michal Duzynski, Hannes Grünewald, Dmitri Naumov, Ralf Trabitzsch, and Holger Weiß

Naturally occurring radon-222 (Rn) is a widespread indoor air pollutant, posing a potential health risk for humans, particularly elevating the risk of lung cancer in indoor living and working spaces. One highly promising solution for existing buildings, requiring relatively minimal technical effort to reduce indoor radon, is the installation of a ventilation system.

As a proof of concept, a series of different ventilation experiments, utilising a decentralised ventilation system with heat recovery (inVENTer GmbH, Germany) were performed in an unoccupied ground-floor flat in Bad Schlema (Germany).

The flat was divided into three individually controllable ventilation zones using strategically positioned ventilation devices, controlled by a novel real-time measurement system for indoor radon activity concentration [Rn] (Smart Radon Sensors by SARAD GmbH, Germany) in each room. This innovative approach to eliminate indoor radon by employing [Rn] as a control parameter enabled automated switching between different ventilation modes or the option to deactivate the system entirely.

Over three years, the different ventilation experiments successfully reduced elevated indoor radon levels from up to 7000 Bq/m³ to 300 Bq/m³ and below. The effectiveness varied based on factors such as the initial room-specific radon levels before each experiment, the performance level of the fans and meteorological parameters.

Furthermore, we developed a true-to-scale three-dimensional Computational Fluid Dynamics (CFD) model based on the actual flat, enabling the quantitative interpretation of various ventilation experiments within a CFD environment. The CFD model utilised a stationary k-ε turbulent flow model to simulate ventilation-induced airflow inside the flat and was coupled with a transient transport model for radon simulation.

For the development of the CFD model, the "Cross-Ventilation" experiment was chosen. This experiment successfully achieved a room-specific reduction of indoor radon levels from approximately 3,000 Bq/m³ to about 300 Bq/m³. To precisely capture the impact of ventilation on indoor radon, the initial radon values for each room were utilised as initial conditions for the transient radon transport model.

Base case results showed an overestimation by the model in radon level reduction due to ventilation. Parameter adjustments of the inflowing radon and the airflow velocity at the inlet resulted in good agreement between experimental values and the CFD model's outcome.

In summary, this study highlights CFD modeling as a versatile tool for evaluating and optimising ventilation systems, offering valuable insights into the mechanism of managing the air quality in complex real-world indoor environments with elevated radon levels.

How to cite: Altendorf, D., Wienkenjohann, H., Berger, F., Dehnert, J., Duzynski, M., Grünewald, H., Naumov, D., Trabitzsch, R., and Weiß, H.: Cross-Ventilation Strategies for Efficient Indoor Radon Reduction: Experimental Data and CFD Simulations, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-12397, https://doi.org/10.5194/egusphere-egu24-12397, 2024.

Posters virtual: Fri, 19 Apr, 14:00–15:45 | vHall X4

Display time: Fri, 19 Apr, 08:30–Fri, 19 Apr, 18:00
Chairpersons: Eric Petermann, Eleonora Benà, Virginia Strati
vX4.28
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EGU24-10152
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ECS
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Georgios Siltzovalis, Ioannis Madesis, Varvara Lagaki, Theodoros J. Mertzimekis, Pavlos Krassakis, Stavroula Kazana, and Konstantinos Nikolopoulos

Radioactivity monitoring in the marine environment exhibits various challenges. First and foremost, the water-induced attenuation substantially limits the detection ability and range of the sensors. Additionally, the harshness and remoteness of underwater locations pose significant obstacles to existing technological solutions towards dense and extended radioactivity mapping of the oceans. The highly ambitious EU FET Proactive Research Programme RAMONES (Radioactivity Monitoring in Ocean Ecosystems) is aiming towards overcoming existing limitations by developing and deploying novel underwater radiation-sensing instruments, enabling direct correlation of marine radioactivity with underwater geological and geochemical processes.

The present study will focus on the analysis of experimental data collected during field experiments conducted in the extended hydrothermal vents of Milos, an island located on the south Aegean Sea that is part of the Hellenic Volcanic Arc. The shallow active hydrothermal system of Milos is associated with calc-alkaline volcanic rocks from basaltic andesites to dacites, and rhyolites that have been deposited over several cycles of volcanic activity. Novel portable γ-detectors based on lightweight CdZnTe crystals, were deployed to acquire in situ measurements from coastal locations at the eastern part of the island. Complementary sediment samples were collected to offer baseline NORM (Naturally Occurring Radioactive Material) levels from Milos Island having attracted a lot of attention recently due to its role as a potential geohazards source. These measurements are used to benchmark the γ spectrometers and prepare them for underwater operation aboard autonomous underwater gliders. Collected data will feed a prototype Risk Information System (RIS) titled as POIS2ON (PrOtotype Information System for SOcioecoNomic stakeholders). POIS2ON database will include datasets accompanied by geoinformation to be visualized though NORM levels heat maps, as well as support detailed Monte Carlo simulations to evaluate the radiation doses on local marine ecosystems.

How to cite: Siltzovalis, G., Madesis, I., Lagaki, V., Mertzimekis, T. J., Krassakis, P., Kazana, S., and Nikolopoulos, K.: Exploring the hydrothermal vent field of Milos Island in Aegean Seausing novel radiation instrumentation, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-10152, https://doi.org/10.5194/egusphere-egu24-10152, 2024.

vX4.29
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EGU24-17908
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ECS
Raffaella Silvia Iovine, Carmine Minopoli, Rosario Avino, Stefano Caliro, Gianfranco Galli, and Monica Piochi

Fumaroles spread out several elements to the atmosphere and may include radon that contributes to environmental radioactivity. The long-lasting vigorous gaseous emissions of the Campi Flegrei volcanic caldera, i.e., Solfatara and Pisciarelli, occur in densely inhabited areas of Naples where the population may be exposed to ionizing radiation from 222-radon. In 2021, we started a study on radon levels from the Solfatara and Pisciarelli fumaroles by using the RAD7 commercial detector, one of the most widely used instruments for measuring 222Rn, either dissolved in water or in soil gas. However, the local high H2S levels and hot temperatures did not allow direct measurements of Rn, resulting in the instrumentation (RAD7) damage. Thus, we developed a proper technique for sampling and measuring radon gas from fumarolic gases in such a “critical” areas to overcome the instrumental issue.

At fumarole sites i.e., Bocca Nuova and Bocca Grande within the Solfatara crater, and Pisciarelli, the gas was periodically sampled in Tedlar® bag of 1 or 3 liters in order to have the possibility to repeat the measurements two or three times to verify the accuracy of the data.

In laboratory, at first, H2S traps were prepared by filling silicone tubes with lead acetate powder, bordered, at both ends, by hydrophilic cotton and closed. Then the fumarole gas was transferred from the Tedlar® bag into a glass tube. Finally, radon gas was measured via a closed loop by using the RAD7. Rn printouts obtained from RAD7 were corrected for the time lag between sampling and measurement. RAD7 and charcoal canister measurements were compared to check the obtained results.

Preliminary results, published in Iovine et al. (2023), demonstrate that the methodology utilized enables the analysis of Rn concentrations even in H2S-bearing gases, discharged from the fumaroles of the Campi Flegrei volcano and, most importantly, without instrumental issues. Fumaroles sampled and analyzed over time according to the methodology adopted, may be suitable for environmental radioactivity assessment and volcanic monitoring purposes as well.

 

Iovine RS, Avino R, Minopoli C, Cuoco E, Caliro S, Galli G, Piochi M. (2023). A procedure to use the RAD7 detector for measuring 222Rn in soil gases exceeding instrumental limits: an application to chemically aggressive fumaroles of the Campi Flegrei area. Rapp. Tec. INGV, 473: 1­18, https://doi.org/10.13127/rpt/473.

How to cite: Iovine, R. S., Minopoli, C., Avino, R., Caliro, S., Galli, G., and Piochi, M.: Determination of 222Radon (222Rn) from the hot and acidic fumaroles gases to the atmosphere of the highly populated Campi Flegrei caldera (Naples, Southern Italy) by using a RAD7 detector: a procedure overcoming instrumental limits, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-17908, https://doi.org/10.5194/egusphere-egu24-17908, 2024.

vX4.30
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EGU24-15380
David Lorenzo, Fernando Barrio-Parra, Humberto Serrano-García, Miguel Izquierdo-Díaz, and Eduardo De Miguel

The Radon deficit technique is a promising screening method for identifying and mapping potential subsurface organic pollution hotspots and thus, for the optimization of intrusive characterization campaigns. Radon (222Rn) a naturally procuded radionucleid and particularly suitable for use as a natural tracer due to its preferential partitioning with non aqueos phase liquids (NAPLs) and and ease of in situ analytical detection (Kram et al., 2001). The ability of the 222Rn technique to locate organic pollution hotspots and provide a semiquantitative analysis has been widely assessed in sites affected by NAPLs (De Miguel et al., 2018, De Miguel et al. 2020). However, the Radon measurement is affected by several confounding factors, such as variations in soil water saturation and ground-level temperature. Machine learning can be used to study and model these confounding factors and improve the interpretation of in situ radon analytical information.

Machine learning is a class of statistical techniques that have proven to be a powerful tool for modelling the behaviour of complex systems in which response quantities depend on assumed controls or predictors in a complicated way (Janik, 2018). The first purpose of this work is the application of machine learning to analyse sampled data of time series outdoor 222Rn. The algorithms "learn" from complete sections of multivariate series (containing measurements of soil water content, soil temperature and meteorological information), derive a dependence model. The model trained in this work can be used to improve the accuracy and reliability of the radon deficit technique, making it a more valuable tool for identifying and mapping subsurface contamination.

 

De Miguel, E., Barrio-Parra, F., Elío, J., Izquierdo-Díaz, M., Jerónimo, García-González, E., Mazadiego, L.F., Medina, R., 2018. Applicability of radon emanometry in lithologically discontinuous sites contaminated by organic chemicals. Environ. Sci. Pollut. Res. 25, 20255–20263. https://doi.org/10.1007/s11356-018-2372-9

De Miguel, E., Barrio-Parra, F., Izquierdo-díaz, M., Fernández, J., García-gonzález, J.E., 2020. Applicability and limitations of the radon-deficit technique for the preliminary assessment of sites contaminated with complex mixtures of organic chemicals: a blind field-test. Environ. Int. 138, 105591. https://doi.org/10.1016/j.envint.2020. 105591.

Janik, P. Bossew, O. Kurihara, 2018,Machine learning methods as a tool to analyse incomplete or irregularly sampled radon time series data, Scie. Tot. Environ.,630, 1155-1167, https://doi.org/10.1016/j.scitotenv.2018.02.233.

Schubert, M., 2015. Using radon as environmental tracer for the assessment of subsurface non-aqueous phase liquid (NAPL) contamination – a review. Eur. Phys. J. Spec. Top. 224, 717–730. https://doi.org/10.1140/epjst/e2015-02402-3.

How to cite: Lorenzo, D., Barrio-Parra, F., Serrano-García, H., Izquierdo-Díaz, M., and De Miguel, E.: Application of machine learning methods to improve the radon deficit technique, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-15380, https://doi.org/10.5194/egusphere-egu24-15380, 2024.

vX4.31
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EGU24-19952
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ECS
Utilizing Artificial Neural Network to Predict Soil Gas Radon in Lecce Province, Italy: Implications for Environmental Risk Assessment and Forecasting
(withdrawn after no-show)
Iman Masoumi, Sabrina Maggio, Sandra De Iaco, Abraham Adewale Aremu, and Olatunde Michael Oni