Non-centralized Water Supply Research Articles

Geographic Information Systems for Water Quality Modeling in the Zhytomyr District Communities

Abstract To ensure safe and quality drinking water for residents of rural settlements who use their own wells, boreholes, and natural sources for domestic water supply, a comprehensive approach to evaluating the quality of underground drinking water using geographic information system (GIS) technologies is necessary. The purpose of the study was to assess the quality of drinking water sources of noncentralized water supply in rural settlements of the united territorial communities (UTCs) of Zhytomyr district and to create geoinformation models based on the research results. The following research methods were used during the research: analytical, field, laboratory, statistical, calculation, and cartographic. The research was conducted in 129 settlements of 12 UTCs of Zhytomyr district, where drinking water samples were collected from noncentralized water supply sources for further analysis in the Measurement Laboratory of Polissia National University, and the creation of geoinformation models using the ArcGIS Pro software package. It has been proven that the average pH level in none of the studied settlements exceeded the norm. The average nitrate concentration in the drinking water from noncentralized water sources exceeded the norm by 1.4–3.5 times, specifically in the water of the Pulyny, Cherniakhiv, Vilshanka, Volytsia, and Oliivka communities, exceeding the maximum acceptable concentration (MAC) limit by more than two times. Only in rural settlements in the Liubar community was the average iron content found to be above the norm by more than 1.9 times. Overall, it was established that the calculated value of the overall water quality class in the Zhytomyr district was 2.03, which is determined as “good,” clean water of acceptable quality. The best water quality was found in the Vilshanka, Cherniakhiv, and Stanyshivka communities, with a quality class range of 1.85–1.93, while the worst water quality was recorded in the Oliivka, Teterivka, and Liubar communities, with a quality class range of 2.13–2.31. It was determined that the highest contribution to the overall water quality was made by nitrate and iron content. The obtained research results and models based on them can be used by local governments of the studied communities to inform the population about the quality of drinking water and to develop a plan for improving the state of drinking water supply with the aim of increasing the level of environmental safety of drinking water.

Quality of drinking water and risk to the health of the population of the south Baikal region (Russia)

Providing good quality water in sufficient quantities is a major challenge in the world. The purpose of the study is to assess the quality of drinking water and the health risk of various population groups in the southern Baikal region (Siberia, Russia) under changing hydrological conditions. Lake Baikal is the largest freshwater body of water and is one of the sites protected by UNESCO. Materials and methods. An analysis of centralized and non-centralized water supply was carried out in the south-eastern part of the Irkutsk region, adjacent to Lake Baikal. The data used are from the Baikal (regional) Information Center for 2011–2022, and they include the results of monitoring the water quality of the centralized domestic and drinking water supply (CDW) with 140 thousand samples, and non-centralized domestic and drinking water supply (NDW) with 108 thousand samples. In all samples, 17 substances were determined. In addition, during the flood period, accompanied by additional water disinfection, trihalomethanes were determined in populated areas exposed to negative impacts. The quality of drinking water was assessed in comparison with the maximum permissible concentrations of substances (MPCs) approved by regulatory documents of Russia. An assessment of the characteristics of drinking water consumption by the population of the Baikal region was carried out, based on interview data from sample groups of the population. The assessment of the risk to public health, due to chronic oral intake of chemicals, was carried out using the values of the hazard coefficient (HQi), the hazard index (HI), individual carcinogenic risk (ICR), and population carcinogenic risk (PCR).Village residents more often use underground water sources (centralized and non-centralized). Residents of cities are provided with water from surface sources (Lake Baikal and the Angara River). Significant concentrations of iron, nitrates, and manganese were found in drinking water used by villagers. Average concentrations of iron - 2.25 mg/dl, manganese - 0.6 mg/dl, nitrates - 135 mg/dl were recorded in the water of underground springs in villages of the Irkutsk region. Among rural residents of the Irkutsk region, 60.8 % live in settlements with non-water supply systems, 28.4 % have mixed water supply.The non-carcinogenic risk for the adult and child population was calculated; HI > 1 was identified for the population using underground water sources. the non-carcinogenic hazard for the adult population, it was found that HI in the Irkutsk region slightly exceeded the standard value (1), amounting to 1.3, and for the child population - 1.6, the main contribution to the hazard index is represented by nitrates. For children of individual rural settlements of the Angarsk region HI = 1.38. The carcinogenic risk for water from underground sources reached in the range 1.56 × 10−5- 2.1 × 10−4 (in some settlements). Priority carcinogens were identified: arsenic (the contribution of which is 56.3–100 %), hexavalent chromium (29.9–35.8 %). A carcinogenic risk for city residents arises from increased disinfection during periods of microbiological contamination (floods, rains, high water levels), and it is associated with the formation of halogen-containing compounds. ConclusionThe need to strengthen the drinking water quality monitoring system in risk areas has been proven by increasing the number and frequency of sampling during flood periods.

Hygienic assessment of iron content in the sources of household and drinking water supply of the Vladimir region

Introduction. One of the most important tasks for ensuring the sanitary and epidemiological well-being of the population of the Vladimir region remains the provision of high-quality drinking water. Due to the fact that most of the population of the region consumes water from underground sources, which is characterized by an increased iron content, a hygienic assessment of the water of household drinking sources was carried out according to the content of this element.
 Materials and methods. The paper presents the data of own research of the Department of Biology and Ecology of the Vladimir State University for 2022. During this period, the authors of the work investigated about one hundred nine samples of water from the household and drinking centralized and non-centralized water supply of the Vladimir region. Water samples were taken in the largest settlements (these are district centers, a regional city and large district settlements) and from drinking water sources of individual farms located in the territory of the region in various districts. The iron content in water was determined on a Hach Lange DR 6000 spectrophotometer using LCK521 and LCK320 cuvette tests.
 Results. Drinking water of the centralized water supply of the Vladimir region in terms of iron content in most administrative centers has been established to meet regulatory requirements and be safe for this indicator for the health of the resident population. Most of the water samples taken from non-centralized water supply sources have significant exceedances of regulatory values. The average excess of MPC in the region is 6.5 times, which is primarily due to the specifics of geochemical the composition of the water‒bearing rocks of these territories.
 Limitations of the study are related to the number of analyzed water samples, which reduces the possibility of interpolation of the obtained data over the entire territory of the region.
 Conclusion. To provide the population with high-quality drinking water, local governments that do not have sufficient funds to purchase de-ironing treatment plants need to initiate a procedure for applying for subsidies under existing state programs for the implementation of measures for the construction, reconstruction, and modernization of water supply systems. Residents of the region are recommended to use household filters to purify water from those components-pollutants that are characteristic of the groundwater of these territories.

Analysis of the quality of groundwater in the Sverdlovsk region

Introduction. The quality and availability of drinking water is a prerequisite for the protection of health and ensuring the necessary living conditions of modern man.
 The aim of this work is to assess the quality of groundwater from sources of non-centralized water supply in in the Sverdlovsk region.
 Materials and methods. Water samples were taken from various groundwater sources including springs, wells, boreholes in the Sverdlovsk region. Water quality was assessed by the following indicators: hardness, oxidizability, pH, content of heavy metals (copper, lead, cadmium, nickel and zinc), nitrate ions. The studies were carried out by titrimetry (hardness and oxidizability), potentiometry (pH and nitrate ion content) and inversion voltammetry (heavy metal content). The degree of contamination of these groundwater with heavy metals was estimated by the Cd pollution index.
 Results. The pH values in the studied water samples are within acceptable values. (except for one sample). The hardness values of the studied groundwater (with the exception of one sample) correspond to the maximum permissible concentration (MPC). A high content of nitrates due to the application of mineral fertilizers and industrial effluents was found in two samples studied. Excess of the standard values of oxidizability due to penetration of municipal wastewater into the groundwater was detected in three samples.
 The revealed strong contamination of a number of underground sources with lead, cadmium and zinc is caused by the action of various technogenic factors.
 Limitations. The number of analyzed samples, the variety of sampling sites, the number of indicators of the quality of the studied water samples, and methods of their determination are limited.
 Conclusion. Thus, the groundwater of the Sverdlovsk region from seven sources of non-centralized water supply were revealed to be contaminated with nitrates, organic pollutants, heavy metals (lead, zinc, cadmium) and characterized by increased rigidity. MPC of lead, cadmium and zinc was repeatedly found to be exceeded in three water samples. The anthropogenic nature of water pollution has been established, mainly due to the proximity of highways and industrial enterprises to water intake sources. The calculated indices of groundwater pollution allowed estimating the level of their pollution as high.

Экологический мониторинг родников г. Ставрополя как объекта резервного водообеспечения

Introduction. This paper presents the results of monitoring the natural spring waters of Stavropol. The complex analysis includes hydrochemical and microbiological analyses. The research of spring water samples was carried out in a period from autumn to spring, 2021–2022, a total of 45 samples from five springs in Stavropol were analyzed – Koryta, Chasha, Mikhaylovskiy, Kholodnyy and Serafima Sarovskogo. Materials and research methods. Sampling was carried out in accordance with GOST 31861-2012. Water. General requirements for sampling. Hydrochemical and microbiological analysis was carried out in accordance with SanPiN 2.1.4.1175-02. Hygienic requirements for the quality of water of non-centralized water supply. Sanitary protection of sources. Research results and their discussion. According to the results of hydrochemical analysis of water quality, contamination of Cd, Pb, Ni, Fe was detected during all periods of the study. There was also an excess of the norm in terms of chlorides in all springs in spring, 2022. It was determined that the WPI and quantitative estimation of microorganisms vary significantly both by sampling dates and by springs. The highest rate of WPI was noted for the Mikhaylovskiy spring in the spring of 2022, and quantitative estimation of microorganisms does not exceed acceptable limits. Conclusions. As a result of the conducted research, it can be concluded that the use of spring water in Stavropol in case of an emergency without risks to public health is possible only from springs – Koryta, Chasha and Kholodnyy, but with preliminary additional cleaning and for a short time.

Gis-Based Assessment of Risk for Drinking Water Contamination to Children’s Health in Rural Settlements

Abstract Nitrates and heavy metals are two of the most significant groundwater pollutants that have an impact on people’s health all around the world. In order to assess their risk to children’s health, this study aims to determine the total iron, manganese, and nitrate content in drinking water sources of non-centralized water supply of the educational institutions in the rural settlements of Zhytomyr region. A total of 114 water samples from wells and bores used by the educational institutions to supply domestic and drinking water to rural residential areas were collected. The Measurement Laboratory of Polissia National University conducted analytical studies. The danger to children’s health was evaluated using the hazard quotient and following the methodology recommended by the US Environmental Protection Agency. The software ArcGIS Pro was used to identify risk zones. The average total iron content in the drinking water of the Berdichev, Zhytomyr, and Novohrad-Volinsky districts was 1.5–2.8 times higher. In all regions, the average manganese concentration did not go above the allowable level. On average, the nitrate content was also below the threshold, but in 22.6–42.9% of the samples, it exceeded the allowable level. Children aged 6–12 years were at the highest risk, and children living in Berdichev district had the highest hazard quotient at 1.972. The fact that nitrates accounted for 67–84% of the total risk indicates the danger associated with the intake of nitrates, even in amounts below the allowable concentration.

Oil sludge barns as objects of accumulated environmental damage and sources of public health risks

Introduction. The research is vital given the task to quantify public health risks caused by objects of accumulated environmental damage. A health risk is a criterion to establish what objects of accumulated environmental damage should be considered priority ones for elimination. Our research goal was to assess and characterize public health risks caused by oil sludge barns located in Argun municipal district in Chechnya, Russian Federation to determine whether this object of accumulated environmental damage should be considered a priority for elimination. The object is typical for this type of waste storage. Materials and methods. Our research concentrated on examining oil sludge barns with the total volume of wastes exceeding one hundred thirty thousand cubic meters. They were located within a settlement less than 50 meters away from the closest residential area. Approximately 40.2 thousand people permanently reside in a zone exposed to the analyzed object. We collected and analyzed background data on the object and performed wide-scale instrumental measurements of soils, drinking water, ambient air and food in the zone influenced by the object. Overall, we accomplished more than 400 tests to estimate safety and quality of soils, drinking water from non-centralized water supply sources and ambient air. Results. We established soils, drinking water from non-centralized water supply sources, and ambient air to be polluted with chemicals typical for oil sludge barns in the zone located next to the object, the closest residential area included. Major risk factors were oil products and their specific components, heavy metals (copper, arsenic, cadmium, and lead), and benz(a)pyrene. The total health risk for people living in the closest settlements was rated as “high”. Limitations. All the obtained estimates, health risk rates included, describe oil sludge barns located in a zone with specific geological and climatic-geographic conditions and in close proximity to residential areas. Conclusion. Assigning the analyzed object into a “high risk category” allows considering it a priority for elimination and it is mandatory to include it in the list of objects that should be eliminated immediately. After the object is eliminated, this territory is aimed for housing development. With bearing this in mind, it seems advisable to perform comparative control examinations of the environment after all the works on eliminating the accumulated environmental damage have been completed.

Assessment of the drinking water quality from natural sources in the Kharkiv city

Improving the reliability and quality of the population's drinking water supply is one of the primary social problems, since the health of the population largely depends on the level of safety of drinking water. Purpose. To determine the composition of spring drinking water consumed by residents of different districts of the city of Kharkiv and to compare the assessment of the quality of drinking water from different natural sources. Methods. Field, laboratory-analytical, statistical. Results. Water samples from 5 natural springs in the city of Kharkiv, from which the population collects water for drinking purposes, were studied. It was determined that according to the organoleptic indicators, no excesses of the normative values are observed, the pH almost does not change seasonally, with the exception of the sample from the "Nemyshlianske" source. The analysis of total alkalinity in the autumn period showed that the standard was exceeded only in samples of the source of the Yunist park and along the street. Klochkivska, and in the spring period - only in the sample of the source on the street. Klochkivska. The total hardness in the samples ranges from 4.9 to 8.04 mmol/dm3 in the autumn period, and from 6.6 to 10.4 mmol/dm3 in the spring period. Excesses in chloride content are not observed in any of the investigated water samples. The iron content exceeds the MPC level only in water samples from the Nemyshlianske spring. The content of aluminum, zinc, cadmium, copper, lead, ammonia and nitrites in the samples is significantly below the MPC level, and almost does not change by season. Conclusions. The formation of the general quality class of water samples from natural sources is significantly influenced by the high level of total alkalinity, total hardness, and iron content in some sources of non-centralized water supply. According to the integral ecological index of water samples in the autumn period from natural sources "Nemyshlyanske", Park "Yunist" and along the street. Klochkivska belongs to the II quality class, i.e. pure water. The integrated ecological index for all other water samples in the autumn period assigns these sources to the I class of water quality - very clean. The calculation of the integral ecological index for water samples from all natural sources in the spring period refers them to the II quality class.

DETERMINATION OF THE HAZARD OF RECREATIONAL WATER USE IN THE CITY KHARKIV (UKRAINE)

The use of polluted water bodies for recreation carries the threat of an outbreak of infectious diseases. A new method for determining the integral indicator of the occurrence of infectious diseases due to recreational water use is proposed. The cause of infectious disease can be not only swimming in water bodies, but also poor-quality food or drinking water, as well as soil pollution on the territory of beaches. Therefore, in the study of infectious diseases associated with recreational water use, it is proposed to calculate weighting factors separately for food products (Ff), drinking water of centralized water supply (Fdvc), drinking water of non-centralized water supply (Fdvd), surface water in places of mass recreation of people ( Fwr) and soil in the beach zone (Fsb) on the basis of research carried out by the bodies of the state sanitary and epidemiological service. Based on the data of state statistics by using a new method, an integral indicator of the occurrence of infectious diseases as a result of recreational water use in the city of Kharkiv was determined. The application of the proposed method will make it possible to make a scientifically based decision regarding the management of water resources and the protection of public health. The authors of the article conducted a study of the quality of surface water according to hydrochemical and bacteriological indicators in the summer of 2021 on 6 beaches of the city Kharkiv. On all beaches, there is a significant excess of the values of biogenic and bacteriological indicators, which creates a threat of infectious diseases. The risk values correspond to the 4th and 5th class of danger (high and very high impact on public health). The analysis of the evaluation of the weighting coefficients allows to determine the main causes of the development of infectious diseases in order to make scientifically based decisions on ensuring comfortable living conditions for the population. Identifying all possible sources of pollution, being aware of changes that may negatively affect water quality, and providing adequate information to the population are important preventive measures for public health protection. Keywords: public health, recreational water use, infectious disease, pollution sources, Kharkiv city.

Ecological and chemical assessment of the status of water bodies in the Vologda region

Pollution of water bodies as a result of natural and anthropogenic activities presents a global problem. The article analyzes the ecological and chemical state and balance in terms of biogenic macro- and microelements of water bodies of non-centralized water supply in the northwestern part of the Vologda region. The study examines the water in 7 rivers, 5 lakes and 4 springs of the Districts of Vologda, Vytegra, Belozersk, Vashki and Kirillov. Based on the composition analysis of the samples taken, the research shows that the water used does not meet the regulatory requirements in terms of turbidity, color, fluoride ion, total iron, chemical oxygen demand (COD). According to microbiological indications the water from the studied sources does not meet the sanitary and hygienic standards in terms of the total coliform bacteria and the total microbial count (TMC) in rivers and lakes. The most polluted rivers for all the indicators considered are the Komela and Kema. The evaluation of the samples according to the physiological usefulness and balance of the chemical composition reveals that water is mainly assessed as well-balanced in terms of biogenic macro- and microelements content being chloride-hydrocarbonate calcium and magnesium-calcium.

Hygienic assessment of manganese content in household and drinking water supply sources of the Vladimir region

Introduction. One of the most important tasks to ensure the sanitary and epidemiological well-being of the population of the Vladimir region is to provide it with high-quality drinking water. Due to the territory of the region to be partially associated with known hydrogeochemical anomalies of excess manganese content in groundwater, a hygienic assessment of the water of economic and drinking sources was carried out according to the content of this element. Materials and methods. The paper presents the data of own research of the Department of Biology and Ecology of the Vladimir State University named after A.G. and N.G. Stoletov for 2021. During this period, the authors of the work examined about 110 samples of water from the household and drinking centralized and non-centralized water supply of the Vladimir region. Water samples were taken in the largest settlements (these are district centers, regional cities and large district settlements) and from drinking water sources of individual farms located in the territory of the region in various districts. The manganese content in water was determined on the analyzer “Fluorat-02-5M” according to HDPE F 14.1:2:4.188-02. Results. The drinking water of the centralized water supply of the Vladimir region in terms of manganese content was established to meet regulatory requirements and be safe for the health of the resident population. In all samples of drinking water, the concentration of manganese is below 0.1 mg/dm3. At the same time, water from underground sources of non-centralized water supply has in some cases an excess of manganese (from 2 to 7 MPC), which is primarily due to the specifics of the geochemical composition of the water-bearing rocks of these territories. Conclusion in order to provide the population of territories using underground water with a high content of manganese, it is necessary to build local modular water treatment plants using modern methods of non-reactive de-ironing and demanganation and using effective modern equipment and filtering materials.

Assessment of risk for the development of non-cancirogenic effects in using water from non-centralized water suppliers in the Tomsk region

Introduction. Iron is a widespread element in groundwater, which is used for domestic and drinking water supply. When using waters from non-centralized sources, deironing of waters, as a rule, is not carried out. When such waters are used for drinking purposes, there is a likely risk of negative effects for public health. Materials and methods. Forty six sources of non-centralized water supply (private wells, water wells, springs) were studied It considered assessing the health risk with oral administration of the components through drinking water into the body. Results. For single samples in the chemical composition of waters there were determined high contents of total hardness, SO42-, Cl-, NO3-. Waters with Fe and Mn concentrations many times higher than the normative values are widespread. The main non-carcinogenic risk is iron and nitrates, which have been identified as warning and high risk levels. For other components, the values of the hazard coefficient are within the range of the minimum and acceptable levels of risk. The probability of occurrence of negative effects for the children’s age group is possible with an iron content of 5 mg/l and more, for an adult - 11 mg/l and more. Limitations. The limitation related to the incomplete route of exposure to chemical components, since only one medium (drinking water) and only one route of exposure (oral exposure) was considered on the risk assessment. This study is also limited by the number of water samples. Conclusion. The health risk associated with high iron content in water has been set for children and adults. For the children’s group (up to 6 years), the risk of developing diseases of non-infectious etiology is significantly higher, than for the adult group, as shown by the results. When iron-containing waters are used for drinking purposes, there is a risk of non-infectious pathologies.

УРОВНИ ИНДИВИДУАЛЬНЫХ РИСКОВ ЗДОРОВЬЮ НАСЕЛЕНИЯ ГОРНОРУДНОЙ ТЕРРИТОРИИ ВОСТОЧНОГО ЗАБАЙКАЛЬЯ

The formation of geochemical anomalies in Zabaikalsky Krai is associated with the activities of mining enterprises. Over a long period of mining operations in Eastern Zabaikalsky Krai, a significant number of objects of accumulated environmental risk have formed, many of which are located in the vicinity of settlements. Mining wastes pose a potential hazard to the soil, underground and surface water sources, and atmospheric air pollution by a wide range of chemical elements. Arsenic, lead, zinc, cadmium, bismuth and tin are the most common chemical elements exceeding hygienic standards. As a result of a study of the water quality of surface water bodies, drinking water of centralized and non-centralized water supply systems, and the state of the soil cover in the territory of Klichka settlement (Priargunsky District), it was established that in the water of noncentralized and centralized drinking water supply sources the excess of hygienic standards for arsenic and chromium was 2.0 – 5.8 TLV and 1.2 TLV, respectively. The maximum excess of the normative values for arsenic, lead, cadmium and zinc was detected in technosol, which are 200.5, 47.2, 14.0 and 5.5 times, respectively. An assessment of children’s health risk from chemical pollution of drinking water shows that the coefficient of non-carcinogenic hazard for most of the studied chemicals does not exceed the allowable value (HQ = 1.0) the exception is the hazard ratio associated with exposure to arsenic (HQ = 2.50). When calculating the total hazard index for the simultaneous ingestion of chemicals, it was found that for the child population the HQ was 4.12, with arsenic making the greatest contribution to the value of the index. The results obtained indicate the need for further study of environmental factors and in-depth biomedical research.

Аналітичний огляд результатів моніторингових епідеміологічних досліджень та інфекційної захворюваності у Кіровоградській області

Objective: The aim of the work is to develop approaches to improving the information and analytical support for monitoring epidemiological studies and infectious diseases in the activities of public health institutions. Materials and methods: The studies were carried out on the basis of a retrospective review of long-term monitoring of epidemiological observations of infectious morbidity and indicators of microbiological and chemical pollution of environmental factors, performed by the state institution «Kirovohrad Regional Center for Disease Control and Prevention of the Ministry of Health of Ukraine». In this case, the following methods were used: dialectical - to determine the essence of information and analytical support for the activities of public health institutions; functional, comparative analysis - to analyze the activities of the state institution "Kirovohrad Regional Center for Disease Control and Prevention of the Ministry of Health of Ukraine"; model, integrated approaches - to develop a model of information and analytical support for the activities of public health institutions and measures for its implementation in practice; methods of statistical analysis - to determine the characteristics of the study of environmental objects and the dynamics of infectious diseases in the population. Results: According to monitoring observations of environmental objects in medical institutions, preschool and general educational institutions, social security institutions of the Kirovohrad region for 2020, which included data from 4196 studies, it was found that almost 15% of them do not meet the requirements of regulatory documents. At the same time, microbiological studies included 1207 samples and measurements, of which 117 samples (9.7%) were inappropriate, sanitary-chemical studies amounted to 2989 samples, of which 146 samples were inappropriate (4.9%) exceeding the permissible standards. The largest number of samples that do not comply with regulatory documents and pose a threat to human health were found in non-centralized water supply 77 samples. The analysis of the infectious morbidity of the population in the Kirovohrad region covered the period of 2018-2020, the dynamic review of which showed that, according to the criterion of general morbidity, the number of cases of infectious diseases is growing over time, while the incidence of infectious diseases in children tends to decrease. A number of shortcomings in accounting and data processing have been identified. Conclusions: The expediency of improving the methodological, software and technological support of the information and analytical direction of the functioning of the state institution "Kirovohrad Regional Center for Disease Control and Prevention of the Ministry of Health of Ukraine" is shown. This will improve the efficiency and quality of the implementation of monitoring studies, as well as the processing and analysis of the obtained data on the state of the environment and public health and the adoption of timely management decisions on its conservation.

PROBLEMS OF DRINKING WATER SUPPLY IN SMALL SETTLEMENTS OF THE SOUTHERN URALS AND THE CIS-URALS

The article discusses the issue of water supply sources for small settlements located on the territory of the Southern Urals and the Cis-Urals. Based on almost 30 years of monitoring of a well used for the water supply of a summer country house, it is shown that the trend of the groundwater level in this area tends to decrease. At the same time, observations of chemical composition of water revealed an increase in the amount of nitrates. It has been established that the level of groundwater depends on the amount of precipitation. Their amount also affects the level of nitrates in groundwater. With an increase in precipitation, the amount of nitrates decreases. The problems shown indicate the need to control the quality of water used for non-centralized water supply of small settlements.

Water Quality from the Sources of Non-Centralized Water Supply within the Rural Settlements of Zhytomyr Region

Abstract The research was conducted within the territories of rural settlements of Zhytomyr region. A total of 72 sources of non-centralized water supply were surveyed. Water quality was assessed by physical and chemical (pH, iron total, total water hardness) and toxicological (nitrites, nitrates, and ammonium) indicators, the content of which was compared with the norms given in the State Sanitary Regulations and Standards 2.2.4-171-10 “Hygienic Requirements for Drinking Water Intended for Human Consumption.” The assessment of drinking water quality was carried out in accordance with DSTU (National Standards of Ukraine) 4808:2007 and with the water quality index (WQI). It was found that the largest deviations from the norm among toxicological indicators were observed for nitrates – 63.9%. In terms of water quality classes according to DSTU 4808:2007, drinking water from sources of non-centralized water supply of villages showed the following distribution: 2.8% of the samples belonged to class 1 (excellent water quality), 72.2% to class 2, and 25% to class 3. According to WQI, 16.7% of the examined sources of non-centralized water supply had excellent water, 63.9% had good water, and 19.4% had poor water. Despite the fact that the water from the investigated sources of non-centralized water supply was of acceptable quality, it is impotable due to the excessive nitrate content. The results obtained show that there is a need for monitoring of drinking water quality from the sources of non-centralized water supply, especially in rural settlements that are not provided with centralized water supply.

Scientific assessment of negative changes in the state of karst groundwater

Centralized water supply in remote settlements is often difficult or impossible, so there is a need to use a non-centralized water supply. The article develops a method for an expert assessment of the negative change in the state of underground karst waters based on a paired analysis of complex indicators of the protection of the aquifer. To assess the vulnerability of non-centralized water supply sources, five factors are used, including the geological structure of the territory, the level of surface and underground runoff, the development of the karst network, precipitation regime electrical conductivity, and mineralization of groundwater. The test was performed using the method of inversely weighted distances (IDW). The vulnerability assessment of karst waters was carried out in the area of 10 key control points identified during the deployment of the hydrogeological control system in 2017. Based on various geological and hydrological indicators, the discrepancy between the vulnerability assessment of karst waters was no more than 15 %. The conditions under which it is advisable to use direct measurements or geoelectric methods to monitor karst groundwater's state are identified.

Vulnerability Assessment of Karst Underground Waters in the Territory of Non-Centralized Water Supply

This paper considers an individual approach to assessing the vulnerability of karst groundwater. It is based on the allocation of such indicators as the geological structure of the observed territory, the concentration of runoff entering the karst channels, and the precipitation regime. Due to regional climatic, hydrogeological and landscape features, a private methodology for assessing the vulnerability of karst groundwater has been developed. To assess the vulnerability of sources of non-centralized water supply, a factor is taken into account, including such indicators as lithology, soil thickness, and the presence of a karst base. The most intense karst processes occur on river terraces, valley slopes. For this purpose, a factor is taken into account, including the level of river flow by hydrogeological posts, underground flow, karst craters, tectonic faults, and vegetation. The development of karst is also promoted by high gradients of the underground flow and underground water outlets in riverbeds and coastal slopes. For this purpose, the factor is taken into account, which is formed on the basis of the criterion of the development of the karst network and the hydrographic network.A relatively large amount of precipitation, especially in the form of rain, and low evaporation determine the increased values of surface and underground runoff and, accordingly, the development of dissolution and leaching processes. Among the external factors, the solubility of minerals is significantly affected by the total mineralization and chemical composition of the dissolving waters. As a result of the observations, spatio-temporal dependencies were identified in the controlled territory.

Algorithm for a Forecast Assessment of Negative Changes in Underground Water in the Territory of Non-Centralized Water Supply

The water quality of non-centralized water supply sources largely depends on the presence of active karst processes. Underground waters of karst origin are a vulnerable component of the geological environment to the influence of modern anthropogenic factors that violate natural hydrogeological and geoecological conditions. One of the indicators of the development of karst processes is the level of river runoff and mineralization of underground water. The results of the analysis of these data make it possible to increase the efficiency of geoecological monitoring systems and to increase the accuracy of forecast estimates of negative changes in groundwater in the territory of non-centralized water supply. When processing heterogeneous spatial data, it is proposed to identify anomalous deviations of parameters. An algorithm has been developed that determines the critical states of karst water vulnerability indicators. A system of equations has been compiled to find the necessary value of the indicators of vulnerability of karst waters, at which the state of underground water passes into a critical state. The paper analyzes data on the salt content and electrical conductivity of groundwater at key points and the number of karst dips. Preliminary hydrogeological work was carried out to determine the conditions of movement of karst waters associated with the lithological heterogeneity of the massif and the degree of karst formation. The results obtained can be used to improve the regional model for assessing the resources of vulnerability and protection of groundwater and forecast the activation of destructive karst processes.

Estimation of health risk associated with consumption of groundwater of apscheronia propinqua at a Prielton region

In modern conditions, health risk assessment activities have become the leading direction in the analysis of potential threats to the health of the population living on the territory of a certain hydrogeochemical province. Based on the analysis of the reporting documentation of state reports in the field of consumer protection and human well-being, as well as ecology and natural resources of the Volgograd region, a priority list of pollutants was selected, due to the chemical nature of the aquifers of the Volgograd Trans-Volga region. The health risk assessment was carried out on the basis of 19 samples taken from non-centralized water supply sources in the Elton rural settlement using the methodology presented in P 2.1.10.1920-04. In this study, for the first time for groundwater in the Volgograd region, a risk-based approach was applied to assess the effect of dissolved toxicants on the health status of the population. The greatest contribution to the formation of a non-carcinogenic risk to the health of adults and children is made by oral exposure to sodium and nitrates. The cardiovascular system is the main critical system that is jointly affected by these toxicants. The total risk of non-carcinogenic hazard (HI) was HI = 0.5262 for adults and 1.2366 for children (taking into account standard exposure factors). The excess of the maximum permissible concentrations of the most significant in the formation of an unfavorable sanitary and ecological situation is primarily due to the geochemical nature of sodium-chloride-sulfate underground waters in the southeast of the Volgograd region, as well as irrational agriculture and the lack of zones of sanitary protection of water sources. The identified risks should be taken into account when exploring new groundwater resources and organizing water supply systems on the territory of the Elton rural settlement. The data obtained are planned to be used in the development of recommendations for the procedure for organizing water treatment in remote arid regions of the Volgograd region in the context of determining priority treatment facilities for sources of non-centralized water supply. Prospects for further research are related to the determination of carcinogenic risks formed by natural heavy metals and agricultural toxins associated with irrational agriculture.