Changes In Hydrogeological Conditions Research Articles

Issues and Methods of Restoration of Kyivan Rus Period Foundation Masonry

Analysis of the main problems of the emergency state of the monuments shows that the main problem of disrupting the equilibrium of the statics of the “footing-foundation-structure” system is the uneven subsidence of the foundations, weak foundation soils, moistening of the foundation soils due to the violation or absence of waterproofing. The subsidence of footings and foundations, changes in hydrogeological conditions, the absence of blind areas and disorganized drainage from the basement, ageing of masonry solutions, a decrease in the strength and bearing properties of stone, brick and plinthiform brick lead to an emergency state of stone walls, their deformation, moistening, destruction of masonry, the appearance of cracks. Unique monuments of the Kyivan Rus period have been preserved in Ukraine. Unfortunately, as a result of the Mongol-Tatar invasion and destruction of the period of atheism in the 1930s, only foundations or separate parts of many temples remained, and some temples were rebuilt during the Baroque period. From many unique monuments, only the foundations remained, in some, in addition to the foundations, walls and individual fragments remained. In this case, the main restoration task was the maximum preservation of artefacts – foundations, walls, side-chapels.

A PERMANENT MATHEMATICAL MODEL OF FILTRATION AND MIGRATION CONDITIONS BETWEEN THE PRIPYAT AND UZH RIVERS OF THE CHORNOBYL EXCLUSION ZONE

Background. Over the past 8–10 years, the radio-hydroecological and hydrogeological conditions of the Chornobyl Exclusion Zone have changed significantly. Under the influence of the decommissioning of the water-containing cooler, the levels, speed and direction of movement of groundwater have changed on a regional scale. New radiation-hazardous objects were created: Storage of spent nuclear fuel (SSNF-2) and Centralized storage of spent nuclear fuel (CSSNF). The impact of climate change on the regime of water bodies has also increased. To study the impact of radiation-hazardous objects on the water environment of the exclusion zone, to forecast changes in hydrogeological conditions under the influence of climate change and man-made loads, it is necessary to create an updated model of filtration and migration conditions with the possibility of its further adjustment and improvement. Methods. In creating and developing a constant mathematical model based on the finite difference method, the geological and hydrogeological conditions of the research area were considered. Spatial constructions were also carried out to visualize the geological structure using GIS technologies. The filtering scheme was drawn up for computational operations. The QGis program was used to construct the surfaces of geological horizons, and the Visual MODFLOW program was used to develop the filtration model. Results. A model of filtration and migration conditions of the Pripyat-Uzh interfluve of the Chornobyl Exclusion Zone was constructed. The distribution of groundwater levels and heads in the Buchach aquifer was obtained. Forecasts of the paths, directions and time limits of the spread of pollutants with underground water from radiation-hazardous objects have been made. We carried out forecasts of the impact of changes in the boundary conditions of the aquifer on the hydrodynamic parameters of groundwater to justify project decisions on improving the network of observation wells and determining the conditions of flooding of the Chornobyl nuclear power plant site. Forecasts of the impact of global warming on the underground water regime have been carried out. Conclusions. The forecast field of pressure distribution demonstrates the possibility of improving the radiological state of groundwater as a result of: increasing the thickness of the aeration zone and its sorption capacity and accelerating self-purification due to the growth of underground flow gradients. It is important that the unloading of polluted groundwater will not take place in the Pripyat River, but in the isolated residual lakes of the former cooling pond. It will take about 20 years for groundwater to reach the lakes from the Chornobyl nuclear power plant site.

Geoecological and economic consequences of creation, drainage and possible variants of restoration the Kakhovsky reservoir

In the article, in the aspect of engineering and geological safety of structures and communications, the long-term hydrogeological consequences of the support and drainage effects at coastal areas of destroyed Kakhovsky hydro node reservoir as a leading eco-forming component of a giant natural and man-made geosystem are considered. In particular, it included Zaporizhia NPP, the largest in Europe, and the largest irrigation systems in Ukraine. The consequences of the hydrodynamic disaster due to explosion of Kakhovskaya HPP, the dynamics and current state of drainage of the bed of its reservoir are briefly described, according to the data of GIS analysis of space images. And also – the state of hydrogeological and engineering-geological conditions in the reservoir support zone at the time of disaster and in retrospect. A calculated assessment of changes in hydrogeological conditions for the next 10-15 years has been carried out. Long-term natural and man-made threats that arose as a result of such changes in hydrogeological (geofiltration and geodynamic) conditions are named. The set of socio-economic threats that arose due to the negative consequences of Kakhovsky reservoir existence and draining is described. It is emphasized that the restoration of hydrotechnical and water management parameters of the reservoir in the previous values (according to the conservative version) will lead to secondary geospatial water saturation of subsiding loess-loamy silty-clay floatingable rocks that have already undergone deformations due to a decrease in geotechnical stability during the initial flooding and subsequent drainage. This will start a new stage in the formation of dangerous violations of stress-deformed state of coastal slopes, of Zaporizhzhya NPP responsible structures foundation and in nearby cities and towns. A socially and ecologically favorable option for the rehabilitation of affected region is possible only on the modern European ideological and technological basis of taking into account the maximum permissible changes in the hydrological network, i.e. by means of: creating a cascade of low support channel reservoirs with locks and small hydroelectric power stations, reconstruction of riverside ponds and water supply systems, transfer of domestic water supply to underground sources, irrigated lands – for drip irrigation, ecological reclamation and afforestation of drained lands.

CHANGES IN HYDROGEOLOGICAL CONDITIONS DURING BOGGING IN THE SOUTHEAST OF THE WEST SIBERIAN PLAIN

Link for citation: Savichev O.G. Changes in hydrogeological conditions during bogging in the southeast of the West Siberian plain. Bulletin of the Tomsk Polytechnic University. Geo Аssets Engineering, 2023, vol. 334, no. 10, рр. 187-198. In Rus. Relevance of the research is determined by the need to understand the mechanisms of interaction between groundwater, swamp and river waters in conditions of severe swampiness in the taiga zone of Western Siberia to solve a number of scientific and engineering problems both at present and in the future. The aim: quantitative assessment of changes in the levels of groundwaters during the characteristic periods of swamping of the southeast of the West Siberian Plain: 1) the beginning of an intensive spread of peat swamps with a peat deposit thickness of 0,3 m or more; 2) oligotrophization of swamps. Methods: methods of mathematical modeling, statistical methods. Results and conclusions. The author has carried out the analysis of peat deposit structure in the southern part of the Chaya river (a tributary of the Ob river) catchment area. The large-scale formation of peat swamps (with a peat thickness of 0,3 m or more) in the area under consideration occurred approximately 4 thousand years ago; the oligotrophization of the peat deposit (on a regional scale) occurred approximately 2,0…1,5 thousand years ago. In both cases, the main part of the swamps presumably could be attributed to the lowland type, but compared with the modern period in the first case their total area was 2 times less, and in the second was 1,7 times more. Taking into account these estimates, the average values of infiltration Inf and filtration coefficients Kf were determined, the ratio Inf/Kf dependence on the area of low-moor peat swamps was obtained, and groundwater levels were calculated at the present time and for periods of 1,7 and 4,1 thousand years ago. During the oligotrophization of the peat deposit (approximately 2,0...1,5 thousand years ago), with a high probability, there was a deterioration in water exchange between swamps and underground aquifers and an increase in groundwater levels. The beginning of intensive regional swamping (about 4 thousand years ago) occurred against the background of intense water-erosion processes. This results in accumulation of river alluvium accompanied by a rise in the levels of river water and then groundwater.

The Influence Of Rock Mineralogy On Groundwater In The Kampungbaru Formation,Coal Mining Area, Anggana And Surrounding Area, District. Kutai Kartanegara

Coal mining activities using the open pit mining system method will have impacts, both positive and negative impacts, positive impacts will cause changes in improving socio-economic life, while negative impacts will affect changes in hydrogeological conditions and environmental changes such as increasing soil/rock acidity so that it will cause water contaminated. This condition has an impact on decreasing the quality and quantity of groundwater as a source of clean water. The purpose of this study was to determine the hydrogeological conditions around the study site, and the influence of rock mineralogy as a potential source of groundwater contamination, especially in the Kampungbaru Formation. The methods used to obtain data such as; pumping test, rock mineralogy analysis (knowing the characteristics) by conducting studies; petrography, microscopic analysis of ore, XRD analysis, XRF analysis and analysis of the potential of acid mine water, while knowing the chemical characterization of water by analyzing the concentration of anion cations, and classifying water classes. Knowing the characterization of rock mineralogy and water chemistry, the level/value of potential groundwater contamination in the study area will be known. The hope of this research is to know and understand the characteristics of mineralogy of rocks and groundwater chemistry, as well as hydrogeological conditions in Kampungbaru Formation, so that groundwater contamination can be known. Specific benefits of the research, which is to explore more detail hydrogeology of the mine and surrounding areas, to understand the characteristics of rock mineralogy and the characteristics of groundwater chemistry, and to know the source of groundwater contamination of the research area. Practical benefits can provide information to the public and government about the potential of good quality groundwater around the research area and know the groundwater location of good quality. The results of hydrogeological studies, study of mineralogy characterization and groundwater chemistry will be obtained conclusion such as: 1) Characteristics of aquifer in Kampungbaru Formation included in the category of productive aquifers. 2) Mineralogy of rocks affect the chemical concentration .. 3) Kampungbaru Formation has the content of metal mineral elements and water chemical concentrations that contain many sulphide compounds as acid mine formers. Stratigraphy of the study area is included in the Kampungbaru Formation and is part of the Kutai Basin (Kutai Basin). Lithology The Kampungbaru Formation consists of a rocky outcrop with sandstone with coal insertions and sandstone units.
 
 Keywords: Hydrogeology, characteristics of mineralogy and groundwater chemistry, contamination

Impact of longwall mining on slope stability – A case study

AbstractIn recent decades, many open pit (OP) mines have either already made the decision or are at the planning stage to change their mining activity from OP to underground (UG) to remain competitive. Technically, before the OP ends its operation, both OP and UG mining will have to be operated simultaneously for a certain period of time. It is well known that UG operation causes subsidence, discontinuous deformations, and changes in hydrogeological conditions. In case of UG operation located below the OP mine, slope deformation can be expected as a result of subsidence induced by UG exploitation.This paper presents a numerical analysis of slope stability under the influence of the longwall mining operation at the Cao Son OP mine in Vietnam. All calculation variants were performed using the Finite Difference Method code, FLAC. In order to evaluate slope stability of the OP slope, various geometry configurations showing advances of both OP and UG extractions were examined. Based on the outcomes, assessments on OP slope are presented, and then, practical actions regarding the location and direction of UG extraction are recommended, with an aim to minimize the impact of underground mining on OP slope.

Changes in hydrogeological conditions at the territories adjacent to tailings storage facilities in Kryvyi Rih iron ore basin

Tailings of mining and processing plants of Kryvbas are new areas of groundwater supply which have led to significant changes in the hydrodynamic and hydrogeochemical regimes of aquifers. The purpose of the research was to assess the degree of damage to the areas adjacent to the tailings of mining enterprises by dangerous The purpose of the research was to assess the degree of damage to the areas adjacent to the tailings of mining enterprises by dangerous hydrogeological processes, flooding and inundation. The quantitative regime of groundwater is in a stable state and corresponds to the modern conditions of operation of industrial facilities. During the research, chemical pollution in groundwater of all aquifers was recorded. At the time of research, there was an increased content of such microcomponents as: carcinogenic cadmium and nickel (up to 1.9-34 MPC; and 2.6-8.4 MPC, respectively); non-carcinogenic lead (up to 1.7-7 MPC); manganese (up to 2-320 MPC); bromine (up to 14-94 MPC) in the groundwater of all aquifers in the north. In the center, there was the accumulation of abnormally high concentrations of elements such as iron, manganese (up to 36-1420 MPC rate of 0.3 mg / dm3 and 1.3-66 MPC rate of 0.1 mg / dm3, respectively, and a significant increase in the value of dry residue and the content of major macrocomponents in all aquifers. In the south for the modern period there is pollution of groundwater of the Quaternary and Neogene systems with such elements as total iron (15-2800 MPC), manganese (1.9-132 MPC), sometimes vanadium, cadmium. The geochemical essence of the formation of the chemical composition of polluted waters lies in the intensity of changes in the hydrogeochemical system and in the change in the migratory properties of chemical elements. The newest techniques and scientific developments on localization and the prevention of migration of heavy metals with the subsequent pollution of waters are required.

Forecast of radionuclide migration in groundwater of the zone affected by construction drainage at the Leningrad NPP-2

The distribution of natural (at the level of global background) and technogenic radionuclides in groundwater of the industrial zone in Sosnovy Bor town, where several nuclear power facilities are operating, was analyzed. The main technogenic radionuclides recorded in groundwater samples are cesium (137Cs), strontium (90Sr), and tritium isotopes. The first two aquifers from the surface are subject to contamination: the Quaternary and the upper zone of the Lomonosov aquifer. Based on extensive material on the engineering and geological studies of the work area, a 3D geological model and hydrodynamic and geomigration models of the industrial zone were constructed. By means of modeling, the extent and nature of changes in hydrogeological conditions of area resulting from the construction and operational drainage of the new stage of the Leningrad Nuclear Power Plant (LNPP-2) were determined. The “historical” halo of radioactive contamination of groundwater forming (1970-1990) at the site adjacent to the NPP, where the storage facility of low- and medium-level radioactive waste is located, falls into the zone of influence. Interpretation of monitoring data allowed obtaining the migration parameters for predictive estimates. Modeling has shown that during the time of the LNPP-2 operation there was no intake of contaminated water by the drainage system of the new power plant.

Numerical model on predicting hydraulic fracture propagation in low-permeability sandstone

Hydraulic fracture propagation is hard to predict due to natural joints and crustal stress. This process may lead to uncontrollable changes in hydrogeological conditions. Therefore, prediction and control of fracture propagation are paramount to permeability increase in ore-bearing reservoir. The coupled fluid-solid model was utilized to predict the hydraulic fracture propagation in low-permeability sandstone of a uranium mine. For this study, the model was modified to allow fractures to propagate randomly by using the cohesive zone method. The simulation was developed on a three-step process. First, geological data required to run the model, including crustal stress, strength and permeability, were assembled. Next, fracture propagation under different conditions of stress and injection volume were simulated. In the final step, experimental data required to validate the model were obtained. The simulation results indicate that the principal stress, distribution and orientation of natural fracture have vital influence on fracture propagation and induced complex fracture network. This work provides a theoretical basis for the application of hydraulic fracture in low-permeability sandstone reservoir and ensures the possibility to predict the generation of complex fracture network.

Mechanism of valley narrowing deformation during reservoir filling of a high arch dam

During the reservoir filling of many high arch dams, it was observed that the valley slopes on both sides deformed towards the river. The measured value of valley narrowing lateral deformation (VNLD) reached 89.54 mm by October 2018. This rare phenomenon contradicts the traditional experience of dam engineering and lacks a convincing explanation. An arch dam project in China is selected as a case study to analyze the mechanism of the VNLD. Based on a comprehensive analysis of the geological background and the VNLD measurements, a numerical study is performed to identify the main factors that may contribute to the VNLD phenomenon. It is concluded that the time-dependent valley deformation is due to the rheological behaviour of rock mass with the change of hydrogeological conditions. The artesian water head in the deep-confined aquifer is increased and the mechanical parameters in fault and shear zones are weakened after reservoir filling, which is associated with the specific hydrogeological structures. The rise of artesian water head is the main induced factor that contributes to the uplift deformation, which is observed at the dam site, and can cause the VNLD in the horizontal direction. The simulated results considering these factors agreed well with the observed data.

EFFECT OF SPATIAL VARIABILITY OF SOIL PROPERTIES ON SLOPE STABILITY

Problem Statement and Purpose. On the slope surface numerous deformations are currently observed. These are contraction cracks, cracks with a lowered shoulder, houses movement, landslide stall walls, etc. There is also a retreat of lip of the coastal ledge and of the edge, debris and landslides in the nearlip part of the plateau. In this regard, the study of spatial variability of soil properties and slope stability assessment is an important task.The purpose of the paper is to study the clay soil physical and mechanical properties spatial variability patterns of the slope in Ovidiopolsky district of Odessa region and its impact on the slope stability taking into account the seismic and hydrodynamic forces.Data & Methods. Landslides monitoring on the key area has been carried out by engineering geological survey SMC LLC "Odesgorstroy”. using the results of field (geodetic survey) and laboratory studies. The shear strength parameters were deter­mined by direct shear test for natural and water-saturated soils. The data was pro­cessed analytically and graphically using statistical characteristics. The slope stability assessment was performed using "blocks method" (G. M. Shakhunyants method). Results. It is revealed that the areas where slope soils have high moisture content are weakened areas. Clay soil strength characteristics depend on the degree of their destruction and saturation. The values of these characteristics significantly decreased with the increase in moisture. This leads to the appearance of weakened areas in the landslide massif. When landslide occur, the structural bonds in clay soils are de­stroyed in the slip surface area, which leads to an increase in surface energy, to the hydration of clay minerals and an increase in soil moisture. That is. a synergistic ef­fect is observed in the slip area, which is reflected in the mutual reinforcement of soil weakening processes.The calculation shows that in most cases the decrease of the slope stability coeffi­cients is due to a decrease in the strength properties related to negative changes in hydrogeological conditions.

ГИДРОГЕОЛОГИЧЕСКИЕ ПРОГНОЗЫ В ЦЕЛЯХ ОСУШЕНИЯ МЕСТОРОЖДЕНИЯ АЛМАЗОВ ИМ. В. ГРИБА

Актуальность исследования обусловлена необходимостью вовлечения в промышленное использование весьма сложного в гидрогеологическом отношении месторождения алмазов, на котором добыча руды осуществляется с проведением крупных мероприятий по водопонижению, направленных на создание безопасных условий производства горных работ. Прогнозирование управляемого водопонижения и изменения гидрогеологических условий при эксплуатации месторождения является сложной задачей, требует учета многих природных и горнотехнических факторов и разработки методических приемов ее решения. Цель: разработка методики и выполнение гидрогеологических прогнозов для эффективного осушения при эксплуатации месторождения алмазов им. В. Гриба. Объекты: осушаемые водоносные горизонты и дренажная система карьера. Методы: анализ применения численных методов моделирования для исследования процессов фильтрации при осушении месторождений полезных ископаемых, численное моделирование. Результаты. На основе изучения геолого-гидрогеологических условий месторождения алмазов им. В. Гриба, способа отработки, выделенных осушаемых водоносных подразделений и источников формирования водопритоков к дренажной системе карьера создана численная модель фильтрации подземных вод. Рекомендовано для перехвата части проскока подземных вод в карьер, дренажа падунского водоносного комплекса на участках, где осушение не обеспечивается ВПС, осушение переходной зоны падунских и мезенских отложений осуществлять внутрикарьерными дренажными устройствами. Предложена методика реализации на численной модели внутрикарьерных дрен. Выполнены прогнозные расчеты с целью эффективного осушения месторождения. Методом численного моделирования доказана эффективность применения лучевого дренажа и горизонтальных дренажных скважин для интенсификации осушения падунских отложений в прибортовом массиве карьера, выполнен прогнозный расчет высоты высачивания на бортах карьера с учетом плана развития карьера. Предложены сроки сооружения внутрикарьерных дренажных устройств.

Distribution and genetic types of loess landslides in China

In this study, 14,544 loess landslides collected from the Loess Plateau of China are used to reveal their distribution and origins. Main factors considered include landslide density, regional tectonics, soil properties, geomorphic structure, rainfall distribution, seismic activity, and human activity. Based on these factors, the Loess Plateau is divided into eight zones with high possibilities of landslides that are classified into six genetic types. The first genetic type of clustering distribution of loess landslides is related to several main regional active faults. The second type is related to broken pieces of loess geomorphic structures. The third type is considered to be due to unloading of the geomorphic peripheral slope that can cause the internal structural plane to open and thus controls the prototype and scale of the loess landslide. Change of hydrogeological conditions in the slope softens the loess pedestal and the slippery layer, forming a softening zone and thus controlling the shear crack and slip model of the fourth type of loess landslides. The fifth type is due to seismic activities that can generate additional stress to the Earth's surface and landform slopes, causing the opening of joints and seismic liquefaction. The last type of landslides is caused by human activities by changing the geological structure, hydrogeological conditions, and the inner stress balance of slopes.

Mathematical modelling of soil massifs strained-deformed state under soil water level decreasing

The analytical solutions for the determination of vertical displacements at any point of single-layer and multilayer soil compositions under filtration water flow influence, saline solutions presence and filtration considering soil changing filtration and deformation characteristics have been obtained. The mathematical models of soil filtration and the stress-deformed state from water-saturated ground massifs and bases deformations forecast under internal volumetric forces influence (hydrodynamic forces of the filtration flow, changes in the soils own weight) have been developed and substantiated. Numerical solutions of the corresponding boundary filtration problems and SDS of soil in regions with time-varying curvilinear boundary have been obtained for these mathematical models. They have enabled to perform water-saturated soils and bases deformations forecast under the change of hydrogeological conditions and man-made factors effect.

Ecological-hydrogeological history of the development of the coal industry in the Western Donbas under the influence of a complex of technogenic factors

The Western Donbas is a mining-manufacturing region of Ukraine with a potential for increasing coal extraction in the following years. The operation of mines is followed by intense water drainage of highly mineralized ground water which accumulates in tailing ponds, which were built in the ravines without barriers screening the water-containing rocks. The problem of rational usage and protection from contamination and exhaustion of all types of water sources available for practical usage is relevant for the studied region, and all around the world. The development of a fundamental scientific solution to this problem was started in 1986, when a constantly operating mathematical model (COMM) of the changes in hydrogeological conditions of the Western Donbas was developed. The authors were the Pavlohrad Geological-Survey Expedition (PGSE), the Dnipropetrovsk Affiliate of the Institute of Mineral Resources (DAIMR) and the Department of Geology and Hydrogeology of O. Honchar Dnipropetrovsk National University. It is a regional, multi-functional, constantly improved hydrogeological project limited in space but without a time limit. The COMM of the Western Donbas, along with the most obvious advantages, has one disadvantage. In spite of its small scale (1:100000) , it provides only a general characteristic of technogenic changes in the ground water regime of the territory and cannot constitute a single scientific basis for developing nature-protection hydrogeologic measures. Therefore,it has been supplemented with mathematical models of the territories adjacent to the local objects of technogenic impact on the ground water. This includes tailing ponds, tailing dams, mining dumps and mine drainage. The first three types of technogenic objects have already been sufficiently studied and described in scientific publications (Eugrashkina , 2011 ; Eugrashkina , 2012; Eugrashkina , 2013; Eugrashkina, 2013). This paper focuses on the mathematical models, changes in hydrogeological conditions under the impact of the fourth factor mine drainage. The first three factors contaminate ground water, the fourth causes decreases in the operational reserves as a result of flow of the fresh water from the upper horizons to the productive dried-out layer.

Hydrogeological modelling in the geotechnical forecast

Underground development project activities for structures located below existing level of groundwater can cause changes in hydro-geological conditions on the construction site and adjacent territories and lead to development of unfavourable engineering-geological processes. Article presents results of hydrogeological forecast at the construction site with foundation pit enclosed in diaphragm wall. To recreate existing hydrogeological conditions and to create accurate model, inverse problem was solved with a multivariate selection of the filtration parameters of the modeled system in such way that there was a satisfactory alignment of modeled groundwater levels and groundwater levels marked during well-drilling, and analytical data, acquired during analysis and compilation of existing hydrogeological data. Upon solution of inverse problem to replicate existing hydrogeological conditions on the model, a series of forecasting tasks was undertaken to assess the impact of planned construction on hydrogeological situation of the construction site and adjacent territories. Construction was modelled in a multi-variant setting for a completely impermeable diaphragm wall and a permeable diaphragm wall with coefficient of filtration of 0.005 m/day. It is advisable to provide a comprehensive hydrogeological and geotechnical forecast at the design stage as it helps to predict how changes in hydrogeological regime affect deformation behaviour of surrounding buildings.

Определение инфильтрационного питания подземных вод аналитическими и числен-ными методами

The definition of infiltration nutrition is an important and compulsory component of the complex prognostic hydrogeological task.Adequacy of mathematical models of changes in hydrogeological conditions of technogenically disturbed territories depends on a number of factors.Namely, from the accuracy of the quantitative evaluation in time and space of all the regimen-forming factors also from infiltration nutrition. This quantity in the Poisson-type and more complex filter equations is present as a free constant term and is interpreted as a boundary condition of the second kind over the groundwater level. In accordance with known classifications, its definition refers to the scientific category inverse problems. Practical experience of the leading hydrogeologists of Ukraine shows that the most effective methods of its determination, in which the initial data are multi-year observations in time and space. The article reviews the existing methods with author's examples of their application with a minimum of initial information under simple hydrogeological conditions, to relatively complex ones, taking into account the filtration anisotropy. Developments are proposed with the solution of nonlinear equations with a minimal sufficient amount of initial information. The continuation of these studies will be the solution of the direct hydro-geological problem Prognosis of the level with an orientation toward landslide areas of the city of Dnipro. In all types of calculations, the regime observations made by KP Yuzhukrgeologia and outlined in the background report documents, as well as the hydrogeological parameters determined by the results of pumping out, were used as the initial data. The structure of the work is consistent in style from simple to complex. As a result of the conducted researches, it is recommended to build a new regime observational network. The observational network will include five wells. Three wells will be located along the current line, and three - across the groundwater flow. Such a network will make it possible to study in greater detail the change in the groundwater table and obtain the most reliable data. All the methods considered are applicable for determiningthe magnitude of infiltration feeding in the study area according to the data of regime observations. After carrying out the research, it can be concluded that the methods described are suitable for solving the stated problems without limitations in the regime observations. The methods presented are in good agreement with each other. This is a confirmation of high reliability. Infiltration nutrition in different years has positive and negative values. In the multi-year section, the value in the sum is positive. This ensures a very slow rise in the water table.

Hydrogeochemistry and water-rock interactions in the urban area of Puebla Valley aquifer (Mexico)

The urban area of Puebla Valley aquifer is seated in Puebla City and neighbor municipalities. Puebla is the fourth largest city in Mexico, where there are significant industrial zones and a large population. Water needs are almost exclusively met by groundwater, which has brought intense exploitation of groundwater resources and water quality degradation. The present study investigates the hydrogeochemical changes in groundwater, particularly focuses on the chemical changes produced by upwelling mineralized water. These concentrations may represent potential risks to the health of the population.The groundwater presented five types of families Ca-HCO3, Mg-HCO3, Mix-HCO3, HCO3-Ca-SO4 and Ca-SO4. The high concentrations of sulphates, calcium and magnesium are reflected in high TDS and Total Hardness. The samples collected showed detectable concentrations of F−, Fe, Mn, Ba, Sr, Cu, Zn, B and Li. The limitations for its use as drinking water are given by the high values of TDS, sulphates, total hardness and Mn.Geochemical modeling using Geochemist's Workbench (GWB) and PHREEQC software enabled the computation of the saturation index of mineral phases with ions in solution and speciation ions. Groundwater was initially in equilibrium with calcite; however, due to the changes in hydrogeological conditions, gypsum and dolomite are being dissolved until new equilibrium conditions are met. The additional calcium and carbonate in the water causes calcite to become oversaturated and to precipitate. Evidence of dedolomitization reactions and common ion effect is illustrated by concurrent increases in calcium and magnesium concentrations in the groundwater.

Influence of changes in hydrogeological conditions on industrial safety of buildings and structures

Technical condition surveys of a number of multi-purpose industrial facilities have shown that the hydrological conditions of the occupied sites often change in the course of operation. This is especially often observed in oil refining and petrochemical industries, the distinguishing feature of which is high water consumption for cleaning the machines and for general cleaning; with a low culture of the facility operation, water often flows out of the main water conduits, and when the drainage systems are disturbed, basement soils are steeped and plant territories are watered. This was observed even at sites where, at the time of the construction of the facility, the groundwater was buried deep enough and did not affect the surveyed building. Monitoring one of the processing plants made it possible to identify the source of flooding and investigate the nature of the change in the groundwater surface after long-term operation of the facility. The results of this work are given in this article.

Vulnerability Assessment of Groundwater Inrush from Underlying Aquifers Based on Variable Weight Model and its Application

Groundwater inrush from aquifers underlying coal seams is a serious geohazard during coal mining in China. Its occurrence is affected by multiple factors, while the importance of these factors may change over the entire mining area. Traditional model with constant weight cannot reflect the influence of index value mutates with changes in hydrogeological conditions on the comprehensive evaluation value. The theory of variable weight model is thus proposed to evaluate the dynamic processes involved in groundwater inrushes. The model is applied to the Yuzhou coalfield in north China to demonstrate the construction process of the variable weight model and to verify its improvement over the traditional constant weight model in assessing the vulnerability of groundwater inrushes from the underlying aquifers. This innovative method offers not only another tool on assessment of groundwater bursting but also has practical significance in reducing water geohazards in mines.