Total Alpha Activity Research Articles

Radon in water and soil cover in the coastal zone of Issyk-Kul

The article summarizes the results of the study of the Issyk-Kul coastal zone - exposure dose, total alpha- and beta-activity, radon in the lake water, and soil cover. Our studies have established that radionuclide contamination is mainly natural in some coastal areas (thorium sands of Zhenish and Ak-Terek) and of natural-technogenic nature in the area of Kadzhi-Sai tailing dump. The nature of contamination is spotty, where rocks are enriched and located closer to the soil cover. Gamma-radiation exposure dose rates of the coastal zone of Lake Issyk-Kul by soil types showed that in general at the background level (from 19 ± 3 to 34 ± 6 µR/h) and below the accepted norm. On separate natural-technogenic sites (Kadzhi-Sai tailing dump, thorium sands Zhenish and Ak-Terek) gamma radiation exposure dose rate, total alpha-activity, and isotopic composition are increased from 2 to 8 times compared to background sites.

Standard addition method for the rapid analysis of 226Ra, gross alpha–beta and total radium isotope activities in surface water of Maritsa River, Türkiye

This research aimed to determine the activity concentration of 226Ra in the natural radioactivity of the surface water of the Maritsa River, Türkiye. The gamma spectrometric analysis was conducted by using 3′′ × 3′′ NaI(Tl) and (HPGe) detector. Since the direct measurement method could not acquire reliable results, the mean activity concentration of 226Ra was calculated as 0.62 Bq L−1 with the “standard addition method”. The mean values of the gross alpha/beta activities and the total radium alpha activity concentration were measured. The results are 0.013 Bq L−1, 0.304 Bq L−1, and 0.014 Bq L−1 respectively.

Variation of total alpha and beta activities and Rn-222 concentrations in the water supply system of an Italian volcanic region: How safe is tap water for human consumption?

Total alpha and beta activities and Rn-222 concentrations were determined in water from different sections of seven aqueducts belonging to the water supply system of Campania region (Italy), known worldwide for its volcanism. Statistical analysis was performed on data to account for their variability across the aqueduct sections, and results were discussed considering the geology of reservoirs, the potential mixing processes occurring along the pipe network, the building/constituting materials of the aqueduct sections, and the integrity of the infrastructure. Guidelines proposed by Italian and international regulation entities were considered to determine if total alpha and beta activities and Rn-222 concentrations found at the taps of the different aqueducts should be considered detrimental to public health. Based on a deterministic and a stochastic approach, a health risk assessment was also tested for Rn-222, assuming direct ingestion and showering as potential exposure pathways. Results showed that applying guidelines returned an absence of hazard, whereas risk assessment returned a high probability of exposure to unacceptable Rn-222 doses for some aqueducts. Beyond the usefulness of obtained results to plan actions to improve the safety of drinking water in Campania, our outcomes represent a warning for bodies dealing with public health at any level: the use of guidelines can bring an underestimation of the risks exerted by the exposure to Rn-222 on human health. Further, using a probabilistic approach in risk assessment accounting for uncertainty can favor risk forecasts based on more “realistic” scenarios.

RECONNAISSANCE SURVEY OF MOTHBALLED URANIUM MINING FACILITIES AND SETTLEMENTS IN THE SOUTHERN PART OF THE NORTH-KAZAKHSTAN REGION

This paper provides data of the reconnaissance (preliminary) radiation survey of mothballed uranium mining facilities (MUMF) and adjacent settlements in the southern part of the North-Kazakhstan region (NKR). It is shown that, according to the level of EDR values, MUMF locations, when the public periodically stays in these areas, do not pose any radiation hazard. The exception is Grachevskoe MUMF where EDR values reached up to 14.0 µSv/h. Around the settlements, EDR values vary from 0.1 to 0.5 µSv/h. Elevated values are noted on highways. Regulatory values of radon EEVA were also found to be significantly exceeded in Toksan bi vil. A minor excess of radon EEVA was detected in Novoukrainka vil. Exceedance of the content of 238U up to 4 MPC was detected in sources of drinking water supply. Exceedances of up to 5 MPC for 238U were also found in natural waters. The total alpha activity showed an excess of up to 15 MPC. Natural waters exhibit an excess of up to 10 MPC. Based upon the data analysis during the reconnaissance survey, the Grachevskoe MUMF and Novoukrainka settlement were selected for a detailed survey.

The first findings of the study of the territory of the water basin of the Kapshagai Reservoir. Uranium isotope distribution

This article presents the first results of the examination of environmental objects (water, coastal soil, bottom sediments) of the Kapshagai Reservoir water basin. Radionuclide composition of selected samples by alpha-, gamma spectrometry and total alpha- and beta-activity were determined. It has been established that in some water samples, the total alpha activity exceeds the standard of the Republic of Kazakhstan for drinking water, the total beta activity does not exceed the standard. Presents the results of uranium-238, uranium-234, uranium-235 activities and also gives the ratio of uranium-234 to uranium-238 activities, which is an important indicator of water contamination by this element.

Радіаційно-гігієнічний моніторинг у районі Запорізької АЕС в умовах загрози радіаційної небезпеки

Objective: To assess the results of monitoring radiation indicators of the state of the environment in the Zaporizhzhia region under the threat of a radiation accident at the Zaporizhzhia NPP in order to make decisions regarding the use of countermeasures. Materials and methods: As a result of the analysis of long-term observations, indicators of radioactivity in the event of a radiation accident were determined. More than 21,000 measurements of the gamma background of the territory were carried out in 13 settlements of the Zaporizhzhia region. The dosimetry method was used to measure the power of the equivalent dose. The radiometric method was used to study the total radioactivity of drinking water from the water supply network. 21 samples were taken. The study of the total beta activity of atmospheric precipitation and settling dust was carried out by the sedimentation method. A total of 34 samples were examined. Results: As a result of the conducted research, it was recorded that the radiation component in the territory of the region did not change – gamma background levels remained within the range of long-term observations of 10-12 μR•h-1. It was established that the total alpha and beta activity of drinking water meets the requirements of the current legislation. The results of the studies of atmospheric sediments and settled dust show that there is no increase in the total beta activity in the atmosphere compared to the average long-term indicator observed in the period before 1986.

Радионуклидный состав твердых радиоактивных отходов конверсионного производства

The paper overviews the study on the radionuclide composition of solid radioactive waste (RW) held in a near-surface storage facility at a conversion production site. The total α- and β-activity of the waste ranges from 1.2 to 1,250 kBq/kg and from 1.1 to 560 kBq/kg respectively. Three radioactive waste categories have been identified: those with the predominance of 226Ra in combination with short-lived daughter decay products (specific activity of up to 100 kBq/kg); waste with a predominant content of 238U in equilibrium with 234Th, 234Pa (specific activity of up to 30 kBq/kg); waste with a predominance of 210Pb in equilibrium with 210Bi and 210Po (specific activity of 70 kBq/kg). The increased total alpha activity level is explained by 230Th found in the waste. At low 226Ra activities, one can focus on the total alpha activity levels to identify areas with possible high 210Po and 230Th activities. Most of the waste inventory contains uranium with its isotopic composition being similar to the natural one.

Investigation of the radiation situation at the dumps of the mine No. 1 of the LPO "Almaz" five years after recultivation

Introduction. The work was completed on the remediation of dumps located in the area of nine tunnels of mine No. 1 of the Lermontov production association “Almaz” over 2014-2015. The article presents the results of a study of the radiation situation on these dumps five years after the remediation. Materials and methods. During the survey, the methods of pedestrian gamma survey were used using a portable spectrometric complex MKS-01A “Multirad-M” and soil sampling with subsequent measurement of the specific activity of radionuclides using a stationary gamma spectrometer manufactured by CANBERRA. The activity of 210Po and 210Pb was measured using a UMF-2000 radiometric setup after their radiochemical isolation. Results. After the remediation of the dump areas, where gamma ambient dose equivalent rate exceeds 0.5 μSv/h, areas significantly decreased and do not exceed 10% of the total dump area, with the exception of the dumps of tunnel No. 42. On the territory of all surveyed dumps, except for dumps of tunnels No. 10 and No. 26, there are areas where gamma ambient dose equivalent rate exceeds 0.6 μSv/h, which is prohibited in accordance with the adopted remediation criteria. Not all tunnel mouths are isolated. Limitations. It is assumed that comparing the content of radionuclides in soil with the criteria for classifying them as solid radioactive waste 238U and 230Th are in secular equilibrium. Measurements of the total alpha-activity in the soil and comparison with the recultivation criteria for this parameter were not carried out. Conclusion. At present, the radiation situation in some areas of all surveyed reclaimed dumps, except for the dumps of tunnels No. 10 and No. 26, does not meet the requirements established in the remediation project.

Control quality measurements of alpha and beta counter with low back-ground ALBA 2000 v.2.5.6.

The article provides a systematic approach to quality control of measurements of total alpha-and beta-activity using a counter with a low background ALPHA / BETA COUNTING SYSTEM ALBA (mod. ALBA / LLAB) and software ALBA 2000 v.2.5.6. The purpose is to determine the compliance of these objects with the requirements of regulatory documentation. The spectrometry method is based on the physical concentration of radionuclides from the sample volume, measuring the rate of alpha, and beta radiation of the obtained dry residue of the sample, comparing the sample count rate with calibration values of activity, and calculating the total alpha, beta activity of the sample. The primary means of testing is a counter with a low background ALPHA / BETA COUNTING SYSTEM ALBA 200, the lower limit of measurements of the alpha activity, which is 0.02 Bq/l, and beta activity of 0.1 Bq/l, the relative random uncertainty of the measurement result is 60 % with a confidence level P = 0.95. The efficiency of registration on the alpha channel of 43 %, background on the alpha channel of 0,11 imp./min, for a measurement time of 60,000 s, the efficiency of registration on the beta channel of 30 %, background on the beta channel of 1,9 imp./min, for measurement time 60000 s. As a comparison sample for calculating total alpha activity, a sample with alpha radiation, 241Am (geometry 2π), is used. To calculate the total beta activity, a sample of beta-emitter of potassium sulfate with radionuclide is used at 40K (geometry 2π). The weight of the counting sample ranges from 200 to 1000 mg. The activity values are calculated automatically, using the software ALBA 2000, v.2.5.6. Measurement of the total activity of radionuclides in counting samples using the method should be performed only in calibrated geometries. At the same time, the safety requirements, personnel qualifications, and test conditions must be met. Quality control of measurements in the alpha, beta counter ALBA-2000 v.2.5.6. It is carried out in qualitative and quantitative ways.

Оценка «нулевого» радиационного фона территорий населенных пунктов Туркестанской области, расположенных вблизи площадки для строительства АЭС Республики Узбекистан

The construction of a nuclear power plant in the Republic of Uzbekistan actualizes measures for the radiation safety of the population and territories of Kazakhstan. The aim of the study was to assess the radiation situation in the settlements of the Turkestan region located near the impact zone of the nuclear power plant. The investigation includes measurements of ambient equivalent dose rates of gamma radiation, equivalent to the equilibrium volumetric activity of radon and thoron in residential buildings, establishing the total alpha and beta activities, and measuring the specific activity of radionuclides in water soil and food samples. In soil samples taken from the villages of Zhetysay and Zhyly-su, the specific activity of 232Th is 2 times higher than the national average. The total alpha activity of drinking water samples from the village of Zhyly-su is 1,5 times higher than the maximum permissible concentration. The concentration of artificial (137Cs, 90Sr) and natural radionuclides (226Ra, 232Th) in food is within the normal range. Obtaining preliminary results of the research will make it possible to assess the predicted radiation doses for various age groups of the population, and to develop preventive measures during the operation of a nuclear power plant.

Assessing the natural and anthropogenic radionuclide activities of the Pechora River estuary: Bottom sediments and water (Arctic Ocean Basin)

This paper studies the activity of natural and technogenic radionuclides in bottom sediments and surface water of the Pechora River estuary, which is the largest Arctic river within the European part of Russia. The relevance of conducting radioecological studies of this region is associated with active oil and gas activities in the Pechora basin and the presence of potential sources of radiation hazard. The average activities of 137Cs, 226Ra, 232Th, and 40K in bottom sediments were 0.16, 18.72, 13.36, and 373.59 Bq·kg-1, respectively. The average activity of 226Ra in the bottom sediments of the Pechora delta was two times higher than in other rivers of the Arctic basin of the European part of Russia, which is associated with oil and gas activities that are carried out in the Pechora basin. This is due to the fact that the decay products of uranium are the main by-products of oil and gas production. The specific activity of technogenic 137Cs in bottom sediments of the Pechora River delta was low and did not exceed 2.2 Bq·kg-1. We did not detect any radioactive 90Sr in bottom sediments. The low 137Cs activity in the bottom sediments of the Pechora delta was associated with both the larger granulometric composition of the sediments in comparison with the estuaries of the Siberian rivers, and with low concentrations of 137Cs in the terrigenous material (soil) entering the river from the catchment area. This was due to the low levels of 137Cs contamination in the soil of the Pechora river basin. We did not find any negative radiation effects of the underground nuclear explosion “Pyrite” carried out in the northern part of the delta, since there were no other technogenic radionuclides. The values of the radionuclides 3H, 137Cs, 226Ra, 232Th and 40K, as well as the total alpha activity in the surface waters of the Pechora River delta, turned out to be below the detection limit. In surface waters, we were able to determine only the total beta activity, which varied over a range from 19.6 to 59.6 Bq·m-3 with an average value of 33.9 Bq·m-3, which was significantly lower than the radiation safety standards. The values of the radiation hazard parameters were below the world average levels and were not significantly hazardous to the health of people living in the area of the Pechora River delta. We concluded that at present, in the Pechora River delta, there are pastures for reindeer with low levels of natural and man-made radioactivity. These conducted studies are the source material in a series of comprehensive studies of the current radioecological state of the tundra territories of the European part of Russia.

The status and trends in radioactive contamination of groundwater at a LLW-ILW storage facility site near Sosnovy Bor (Leningrad region, Russia)

The article presents results of field studies at a site of radioactive waste storage and disposal facilities (the so-called LD RosRAO site, Sosnovy Bor, Leningrad region, Russia). The objective of the study is to overview the history and occurrence of groundwater contamination to answer the question whether the radioactive plume is historical (formed due to accidents, which happened at the beginning of the operations with the radioactive waste) or the release of radioactive solutions to groundwater is still occurring. The main method used to study the evolution of radioactive contamination is to analyze long-term observations of tritium, total alpha, and total beta activities in groundwater samples. The role of the hydrogeological conditions of the site, such as flow parameters, groundwater flow pattern, inter-aquifer downward groundwater leakage, and water-table fluctuations, in the evolution of contamination plumes has also been analyzed. In the field investigations, the integrity of the storage buildings to potential leaks was confirmed by different indirect methods. It was concluded that there is currently no significant release of radioactive components into groundwater at the LD RosRAO site and that the present conditions correspond to the stage of rehabilitation of the groundwater environment.

Estimation of unattached and aerosol-attached activities of airborne short-lived radon progeny in indoor environments

Inhalation of the airborne short-lived radon progeny is regarded as the most crucial way of internal exposure to the natural radiation dose delivered to the human lung. In this respect, this study aims to determine the unattached and aerosol-attached activities of radon progeny and to estimate some important physical parameters employed to assess the radiological impact of this radiation on humans. For this purpose, radioactive aerosol samples collected on polycarbonate membrane filters to measure total alpha activity by passive alpha dosimetric technique using CR-39 detectors in sixteen different locations including some houses and workplaces in El Jadida city, in Morocco. In addition, the room-specific parameters and aerosol physical processes that affect the unattached and attached activity concentrations were determined. The obtained experimental results by the three-count method and room model parameters were used as input data on a developed PC-based software that we have developed to solve mathematical equations and calculate required physical quantities. Accordingly, the individual activities of radon progeny namely 218Po, 214Pb, and 214Po as well as radon activity concentration were determined. Simultaneously, the unattached and aerosol-attached activity concentrations (Cju and Cja) of radon progeny were calculated based on the room model calculation. Consequently, some radiological quantities used in the calculation of the lung dose were estimated. The results showed that the indoor radon activity concentration in different targeted locations ranges between 38 and 143 Bq. m−3 with an average value of 84.8 ± 9.5 Bq. m−3. The average obtained values of the equilibrium-equivalent concentration (Ceq), unattached fraction (fp), and equilibrium factor (F) at low and good ventilation rates change respectively from (24 Bq. m−3, 0.08, and 0.25) to (34 Bq. m−3, 0.02, and 0.41). Under normal environmental conditions, the average obtained values of Ceq, fp, and F, in houses and at workplaces were (17 Bq. m−3, 0.07, and 0.25) and (32 Bq. m−3, 0.04, and 0.35) respectively. Depending on the different aerosol conditions and obtained values of unattached fraction fp, the calculated average values of dose conversion factors (DCFs) were 8.70 mSv.WLM−1 and 11 mSv.WLM−1 in houses and workplaces respectively. These values were in good agreement with the recommended values by ICRP, which are in the order of 9 mSv.WLM−1 and 12 mSv.WLM−1 for houses and workplaces respectively.

Сумарна альфа-активність та активність радону-222 у підземній воді в різних регіонах України

Objective: We aimed to analyze the results of the measurements of the total alpha activity and activity of radon-222 in the water of artesian wells to establish the geographical regions of Ukraine which require a deep attention to the assessment of the radioactivity of the groundwater. Methods: We used empirical, analytical, radiometric, spectrometric methods and method of mathematical statistics in the study. Materials: We carried out a statistical analysis of the results of the measurements of the total alpha activity and the activity of radon-222 in water samples from the artesian wells of 23 administrative regions of Ukraine studied during 2016 - 2020. Results: Analysis of the results of the measurements of the total alpha-activity and radon-222 activity in the water of artesian wells showed their significant heterogeneity for different regions of Ukraine and a connection with the geological features of the area. The statistical distribution of the values of the total alpha activity and the activity of radon-222 in water samples, diagrams of the range of measured values within the regions of Ukraine and between regions are presented in the work; the measurement results were plotted on the hydrogeological map of Ukraine. Conclusion: The values of the total alpha activity and the activity of radon-222 indicate that these indicators are extremely heterogeneous for the territory of Ukraine and reflect the geological features of the area. The results of the analysis can be useful for making recommendations to collective and individual water consumers, well owners regarding the need in more detailed study of the content of natural radionuclides in the sources of water and the use of the appropriate methods of water treatment in cases of non-compliance with the accepted standards. It is shown that it is necessary to develop a strategy for radiation monitoring of the groundwater quality in the country in order to study objectively the existing state and the achievement of an acceptable quality of the water consumed by the population.

Radioactivity of Bottled Water from Trade Network in Kyiv

In 2018-2019, we examined the radioactivity of 40 samples of bottled water of popular brands produced both in Ukraine and abroad, which were purchased in one Kyiv supermarket. The first stage of the study provided for the identification of total alpha and total beta activities. In the case of excessing their regulated values, we proceeded to the determination of the content of radium-226 and natural mixture of uranium isotopes. The study results evidenced that total alpha and total beta activities of low mineralization water do not exceed the regulated values. Total alpha activity exceeded the regulated value of 0.1 Bq/l ten times in specific cases and total beta-activity exceeded the value of 1.0 Bq/l almost three times for the majority of high mineralization water brands.
 The results of measuring total alpha and total beta activities depending on time elapsed from the moment the sample was prepared to the start of the measurements showed an increase in the alpha activity over time is typical for individual water samples, which indicates the accumulation of radioactivity from radium-226 decay products. However, the results of measuring the activity of radium-226 and a natural mixture of uranium isotopes did not reveal cases of exceeding regulated levels, which allows considering water of all brands suitable in terms of radionuclide content.
 Assessment of radiation doses from consumption of bottled water containing the measured values of radium-226 and natural mixture of uranium isotopes did not reveal exceeding regulated value of 0.1 mSv/year. Only one bottled water brand was an exception, since the estimated radiation dose for it was 0.2 mSv/year for the category of children aged 12 to 17 years with 98 % of its value due to radium-226. Such a radiation dose value was received assuming an annual consumption of 1.5 liters per day.

Практичне використання радіаційних параметрів якості питної води: настанови міжнародних організацій та український досвід

The analysis of the documents of the authoritative international organizations and scientific works was carried out from the point of view of the development of the strategy for ensuring the radiation quality of drinking water. The radiation parameters of the quality of drinking water, the interpretation of monitoring results by screening and recommended levels, the value of the individual dose criterion, as well as algorithms for establishing the frequency of monitoring of the radiation parameters of drinking water were considered. Objective: We analyzed the documents of reputable international organizations and scientific works in terms of the development of the strategy for ensuring radiation quality of drinking water and the features of the practical application of the parameters of water radiation quality in the world and Ukraine. Methods: bibliographic, analytical. Materials: We performed the analysis of the documents of international organizations (WHO, IAEA, ICRP, UNSCEAR), as well as scientific publications on the radiation quality of drinking water in the light of the experience in measuring the content of drinking water radionuclides at the territory of Ukraine. Results: Materials of the international documents and scientific publications demonstrate that the assessment of radiation quality of drinking water requires a balanced analysis. In some cases, based on the results of only one determination of the total alpha and total beta activity, it is impossible to draw an unambiguous conclusion about the suitability or unsuitability of drinking water for consumption. Taking into account the geological heterogeneity of the territory of Ukraine, in order to obtain sufficient data on the radioactivity of groundwater, it is necessary to conduct extensive screening studies of the radiation quality of water in the regions of the country with the involvement of geological and monitoring services, local authorities.

Study using Vetiver grass to treat radioacitve pollution at Sin Quyen copper miner area, Lao Cai Province

The article introduces the research results of using Vetiver grass in radioactive environment treatment (water waste, mud waste) in Sin Quyen copper mine area, Lao Cai province. After 30 days, uranium absorption efficiency reached 77.4% and thorium 83.5%, the total alpha and beta activity of the water dramatically declined, alpha treatment efficiency reached 95.3% while beta treatment efficiency reached 93.7%. The model of radioactive pollution treatment by Vetiver showed high efficiency, simple operation. Therefore, it is very promising to apply the treatment of radioactive sludge, radioactive waste sludge in the process of exploiting and processing Sin Quyen copper ore in particular, the areas of radioactive mineral mining in general.

Provision of the radiation safety of the public of the eastern districts of the Orenburg region for the use of the drinking water from the underground water supply sources

Starting from 2014, several cases of exceedance of the specific total alpha-activity of the natural radionuclides and specific activity of 222Rn were identified in the water of the underground wells in the eastern districts of the Orenburg region. Based on the results of the surveys, a number of settlements were equipped with the systems of aeration of water from underground wells prior to the distribution, but significant expenditures on the technical maintenance of the aeration units lead to their frequent malfunctions. Based on the results of the surveys of the drinking water in settlements of the Adamovskiy, Kvarkenskiy, Novoorkskiy, Dombarovsky, Svetlinsky districts and Yasnenskiy urban district, it was estimated that in some settlements specific activity of 222Rn in drinking water exceeded the intervention levels up to a factor of 10. No exceedances of intervention levels for 226Ra, 224Ra, 228Ra, 210Pb, 210Po and 238U were identified. Based on the results of experiments and analyses the authors performed the hygienic assessment of the indicators of the radiation safety of the drinking water from the underground water supply sources in several settlements in the eastern districts of the Orenburg region, performed the analysis of the effectiveness of the aeration systems, developed recommendations on the provision of the radiation safety of the public of the eastern parts of the Orenburg region for the use of the drinking water from the underground water supply sources and developed proposals on the improvement of the limitation of concentration of 222Ra in drinking water.

Search for α decay of naturally occurring Hf-nuclides using a Cs2HfCl6 scintillator

Residual radioactive contaminants of a caesium hafnium chloride (Cs2HfCl6) crystal scintillator have been measured in a low background setup at the Gran Sasso National Laboratory of the INFN, Italy. The total alpha activity of the detector is at the level of 7.8(3) mBq/kg. The results of direct studies of the α decay of naturally occurring Hf isotopes that have been performed using the “source=detector” approach are presented. In 2848 h of data taking, the α decay of 174Hf was observed with T=1/2(7.0±1.2)×1016 y.

About Total Alpha Activity of Underground Water Sources

Artesian wells remain strategically important sources of drinking water for the Kyiv megacity, especially in the vicinity of radioactively contaminated areas of the Chornobyl exclusion zone. The contribution of groundwater to the total volume of drinking water was indicated. The water from 144 artesian wells was investigated in terms of total alpha activity: 67 of them were drilled up to the Cenomanian aquifer of the Upper Cretaceous, 77 - up to the Bajocian aquifer of the Middle Jurassic.
 Studies have found that the total alpha activity in 39 wells exceeds the regulatory limit, with 37 of the 39 wells supplying water from the Bajocian aquifer. The average total alpha activity of the Cenomanian water is 0.033 ± 0.003 Bq/dm3, the most active water of this aquifer is produced in the Obolon area where the average value equals 0.045 ± 0.004 Bq/dm3. The average total alpha activity of the Bajocian water is 0.115 ± 0.012 Bq/dm3, the most active water of this aquifer is produced in the Obolon and Troyeshchyna areas where the average values equal 0.097 ± 0.010 Bq/dm3 and 0.188 ± 0.018 Bq/dm3, respectively. Therefore, in average, the Bajoian water is 3.5 times more active than the Cenomanian one: the average activity reaches 0.115 ± 0.012 Bq/dm3 against 0.033 ± 0.003 Bq/dm3.
 GIS mapping of the total content of α-emitters in the groundwater of both aquifers was created. The dynamics of the gross alpha activity of artesian water from both aquifers was monitored for the Obolon area. It was determined that when consuming the Bajocian water, two times more alpha-emitters enter the human body than from the Cenomanian water.
 The processing of the results through the spline interpolation with the Spatial Analyst Tools module ArcGIS 10.1 made it possible to analyze this trend for the megacity area: geological and tectonic factors such as block movement of the foundation, unequal incision of ancient watercourses into the pre-Bajocian surface and the erosion of sediments had always had the greatest influence on the enhanced alpha activity of the Bajocian water.