City Of Darkhan Research Articles

Field test of compactability of soaked subsidence soil using heavy tamper

Dynamic compaction, including heavy compaction, is a widespread method throughout the world for improving the physical and mechanical characteristics of subsidence and low-density soils. The results of theoretical and experimental studies have established that the depth of compaction and the density of compacted soils depend on the weight, shape of the bottom, the height of the tamper and humidity, the type of structural connection, and the granulometric composition of the compacted soil. This article discusses the results of compaction with a heavy tamper when soaking loess-like subsidence soil, widespread in the city of Darkhan, Mongolia, to optimal moisture.

Experience of diagnostics and treatment of «foundry fever»

Casting fever is one of the most common occupational diseases that occurs in workers engaged in metal casting, galvanizing steel, or welding galvanized steel. This production intoxication can be individual, and in rare cases be massive. Purpose of the study: to analyze the clinical manifestations, medical care tactics, sanitary and hygienic indicators of the working environment in the event of an acute mass disease in workers of a metallurgical plant in the city of Darkhan (Mongolia), as well as the experience of treating such patients in the Irkutsk Toxicological Center. Material and methods. A retrospective descriptive study according to the medical documents of workers injured in an emergency at the Metallurgical Plant, as well as patients of the Irkutsk Toxicology Center hospitalized due to the “foundry fever” in 1999-2021. Mathematical processing of the obtained results was carried out on a PC using the Microsoft Office 2016 and STATISTICA 8.0 application software package. When testing the null hypothesis of equal shares, the criterion z was used. To analyze the quantitative indicators, the Me median of the interquartile range was calculated (Q25 – Q75). Results. Signs of a “foundry fever” were identified in 71 working foundries of the Darkhan Metallurgical Plant. The condition of 51 people required hospitalization; the rest was provided on an outpatient basis. The most common signs of the disease were: weakness, dizziness, headache, fever, abdominal pain, diarrhea. Against the background of the treatment, the main signs of the disease disappeared within 2-3 days. Weakness and headache persisted beyond more than a week. During sanitary-hygienic research in the air of the working area of the foundry, elevated concentrations of metals were found. Patients of the Irkutsk Toxicological Center revealed similar symptoms and similar treatment results. Conclusion. “Foundry fever” in production conditions can be not only individual, but also massive. Disease prevention measures include technological improvements in the production process and the use of effective personal protective equipment, and when a group or mass injury occurs, it is advisable to use the developed emergency care algorithm.

REMOTE SENSING AND MULTIVARIATE LOGISTIC REGRESSION MODEL FOR THE ESTIMATION OF URBAN EXPANSION (CASE OF DARKHAN CITY, MONGOLIA)

Abstract. Urban expansion and land use and land cover change (LUCC) studies are a key knowledge of efficient local governance and urban planning and a lot contributing to the future sustainable development of the city. The main goal of the paper is to model a future urban spatial expansion by 2029 and 2039 of Darkhan city using Landsat TM satellite imagery (land use and cover change map of 1999, 2009, and 2019) and multivariate logistic regression model. Clark Lab’s (Clark University) IDRISI & TerrSet software applied for the urban expansion prediction and the correlation between expansion and driving factors. On account of multivariate logistics regression modelling, eight physical factors influencing urban expansion identified to predict urban expansion based on USGS Landsat TM imageries (Landsat Multispectral Scanner with 60 m resolution). The regression statistic accounted for the probability of future urban expansion was positive. Overall, the LUCC has estimated the transition of natural cover to the impervious surface in Darkhan city. Our result estimates an increase in the built-up area and slum area during the period 1999–2009 and 2009–2019, represents LUCC was characterized by an external transformation from natural to urban area. According to the future urban growth prediction, the urban area would be significantly spread into the open space and natural vegetation area. The main findings stated here are that Darkhan city is expanding in an unsystematic way, even though the urban growth has not been analysed in detail and has a bad case of urban unregulated sprawl.

Contamination and Health Risk Assessment of Heavy Metals in the Soil of Major Cities in Mongolia

Using the case of Ulaanbaatar, Erdenet, and Darkhan cities from Mongolia, the study aimed to assess the contamination level and health risk assessment of heavy metals (As, Cr, Pb, Ni, and Zn) in urban soil. A total of 78 samples was collected from a variety of functional areas. The geoaccumulation index (Igeo) and integrated pollution index (IPI) were used in pollution assessment, while the health risk was scored using a hazard quotient (HQ) and health index (HI) for non-carcinogenic heavy metals, as well as a lifetime average daily dose (LADD) for carcinogenic heavy metals. The results show that the concentration of heavy metals in the soil samples taken from Darkhan city, which presented “uncontaminated” values in terms of Igeo for all metals, was relatively lower than other cities within the contamination assessment. Furthermore, the Igeo value signified “uncontimated to heavily contaminated” soil in the Ulaanbaatar and Erdenet cities. Typically, as for the IPI that observed similar trends with Igeo, the mean IPI values in Ulaanbaatar, Erdenet, and Darkhan were 1.33 (moderate level of pollution), 1.83 (moderate level of pollution), and 0.94 (low level of pollution), respectively. In terms of the assessment of potential health risk, there was a particular or different level of ingestion, dermal contact, and inhalation exposure pathway for human health. Among these three different pathways, the ingestion was estimated by the main contributor for health risk. Each value of HQ and HI indicated that soil heavy metals of studied cities were at a safe level (<1) or had the absence of a significant health risk there. In addition, the potential health risk for children was greater than for adults, where heavy metal values of HI for children had a high value compared to adults. We estimated carcinogenic risks through the inhalation exposure, and as a result, there were no significant risks for human health in the studied cities from three elements (As, Cr, and Ni).

Geochemical transformation of soil cover and woody vegetation in the largest industrial and transport center of Northern Mongolia (Darkhan)

Geochemical changes in the surface soil horizons and in the trace element composition of the leaves of poplar hybrids under the influence of emissions from the industry and transport hub of the city of Darkhan (Mongolia) were studied. Based on the data of the geochemical survey, priority pollutants in various land-use zones of the city and regularities of their spatial distribution were determined.Atmospheric emissions from thermal power and metallurgical plants, and leather factory resulted in the accumulation of Zn, As, Cd, Cu, and Ni in the soils and poplar leaves. The widespread distribution of yurt quarters utilizing brown coal from Sharyngol and Baganur mines for domestic purposes led to the formation of the areas with abnormally high concentrations of Zn, Cd, Sb, Ba, and Sn in the soils and Cd, V, Ni, and Cu in the leaves of poplar. An increase in the urban population and in the number of vehicles that, until recently, used leaded gasoline caused increased concentrations of Zn, Cd, Cu, and Ba in the soils and of Zn and Pb in the leaves of poplar.Ba and V represent the greatest danger in Darkhan; their coefficients of ecological hazard exceed established international standards by two or more times. Multielemental pollution of surface soil horizons is characterized by a low level of environmental risk throughout the city, except for the local anomalies near the metallurgical plant and the thermal power station.It is known that the main route of admission of potentially toxic elements into assimilating organs of urban vegetation is foliar absorption. The ratios of trace elements in poplar leaves attest to the balanced metabolic processes in poplar hybrids and their generally satisfactory state, except for the local anomalies close to those established for the soils. The Fe/Mn and Pb/Mn ratios are most balanced under the background conditions and display maximum deviation from this state in the industrial zone of the city. The Cu/Zn ratio found in the studied woody plants indicates the imbalance in provision of the enzyme synthesis because of Zn deficiency, detected in the inner yards of the residential high-rise zone.

Health risk assessment based on the contents of potentially toxic elements in urban soils of Darkhan, Mongolia

Toxic element's accumulation in the urban environment not only worsens the quality of air, water, soils, and foodstuffs but also threatens the health of people because of entering human bodies through lungs, stomach, and contact with skin. The aim of this study is to assess the current geochemical and ecological state of the soil cover in the city of Darkhan (Mongolia) and to estimate health risks on this basis. Soil geochemical survey was performed in 2012–2013, the result was a collection of 126 soil samples. The bulk contents of 13 potentially toxic elements (PTEs) were determined by ICP-MS and ICP-AES.The soils of the industrial zone are most heavily polluted and contain increased concentrations of Pb, Mo, Sb, Zn, W, Cr, As, Cd, and Cu (geo-accumulation index Igeo = −1.87–4.13), which form four multi-elemental anomalies. First contrasting anomaly extends from thermal power plant in the north–northeastern direction where contamination degree (CD) reaches 39.5–45. Second and third anomalies are located near leather goods plant (CD = 44.2) and metallurgical plant (CD = 33) respectively. The last one is founded in the northern part of the city near granary and railway station (CD = 39.4–42.2). Soils of unused areas and part-recreation zone are not polluted, Igeo < 0 for all PTEs.The most significant impact on human health is exerted by Co, V, Cr, Pb, W, As, and Sb in all land-use zones. These elements contribute more than 97% to the value of health index (HI). Health risk is low for adults (HI ≤ 0.14) and medium for children (HI = 1.16). The HI values for children are above 1 for more than 60% of the city.Oral admission is the main type of element's input (As, Cd, Cr, and Pb) in the human body, it's share in the total risk (TR) of cancer development is 86–97%. The TR values are within 1.09 × 10−5-5.68 × 10−5, which corresponds to the medium risk level. Maximum values are in the industrial zone of Darkhan. The contribution of Cr and As is most pronounced among the studied elements.

CHARACTERISING SEASONAL VARIATIONS AND SPATIAL DISTRIBUTION OF AMBIENT PM2.5 CONCENTRATION BASED ON SHORT-TERM MONITORING IN DARKHAN CITY

The purpose of this study was to survey the seasonal variation of fine particulate matter (PM2.5) concentration and determine spatial distribution in Darkhan city. Air pollution research and reports have been few and far between in most of parts in Mongolia, especially in Darkhan with respect to quantitative aerosol particle concentration. In this study, we utilized “PM2.5sensor” to measure spatial and seasonal variation of particulate matter concentrations in the study area. The monitoring points were chosen by basing on their specific features and set up directly at ambience outdoor. In each season, we carried out measurement at 3 points, which covered the ger district and apartment district areas for one day. Whereas, at one point the ger district was sampled for 4 days in summer. Fine particulate matter concentrations were the highest in the ger district area because there are many households that use coal for their daily heating and cooking, and at the bared surface. As for seasonal variation, in winter pollution reached 400 times higher than other seasons. Furthermore, at the ger district area, PM2.5 concentration was as much as 20 times greater than other points and it was observed that this too had its impact on the apartment district as well. As regards the air quality index, the level of particulate matter in the ger district area is extremely unhealthy to hazardous in winter. While, good and moderate indexes were mostly identified at monitoring points during the springtime.

Assessment of heavy metal pollution of topsoil in settlement area, Darkhan city

This study was carried out to assess the content of toxic heavy metals (As, Co, Cr, Cu, Ni, Pb, V, Zn), determine pollution and spatial distribution of topsoil in Darkhan city which is one of the largest cities in Mongolia, to determine pollution and spatial distribution. The selected study area of Darkhan city was divided into 3 zones (industrial zones, ger districts or livestock breeding zones and private apartments or residential district zones) representing settlement’s characteristics, and 14 points were sampled from topsoil. In order to estimate the level of pollution, the contamination factor, the degree of contamination, pollution load index, and enrichment factor that were formulated by Hakanson, Tomlison, Selvaraj were used in our study. The results were come out by comparing the heavy metal concentration of the topsoil with it`s background concentration. In terms of spatial distribution of heavy metals in the topsoil, heavy metals concentration in ger district and industrial areas is relatively high, but pollution assessment is not very high. As a result of the enrichment factor which was used for assessment of contamination source, the average concentration of 8 elements (As, Co, Cr, Cu, Ni, Pb, V, Zn) at 13 points presented that was derived from natural sources.

Properties of geopolymer binders prepared from milled pond ash

Alkali-activated materials were prepared from pond ash from the Darkhan city (Mongolia) thermal power station. This ash contains about 60 wt % X-ray amorphous material in addition to quartz, mullite, hematite and magnesioferrite, and presents significant storage problems since it is accumulating in large amounts and is a hazardous waste, containing 90–100 ppm of the heavy metals As, Pb and Cr, and about 800 ppm Sr. Alkali-activated materials synthesized from the as-received pond ash achieved compressive strengths of only 3.25 MPa. Reduction of the particle size by mechanical milling for up to 30 min progressively increases the compressive strength of the resulting alkali-activated geopolymer up to 15.4 MPa. Leaching tests indicate that the combination of milling and alkali treatment does not cause the release of the hazardous heavy metals from the product, making it suitable for construction applications.

Integrated urban water management: development of an adapted management approach

The challenge of establishing integrated urban water management (IUWM) lies in the nature of and interaction between various subjects. Following on from integrated water resources management (IWRM), IUWM is structured as a holistic approach. Environmental issues, institutional functions and instruments for planning and management form the basis for integrated urban water management. This paper presents the development of a methodology for identifying, bundling and prioritising measures, taking into account resource orientation and cost-efficiency analysis. The approach is applied to the City of Darkhan, Mongolia’s second largest city, which serves as a model area for Central Asia. The model region has to cope with an extreme continental climate, the livestock agriculture of the nomads, nutrient losses in cultivated agricultural areas, trans-boundary impacts on Lake Baikal and the potential for conflicts through mining activities. Settlement structures are heterogeneous, the cultural imprint of post-socialist structures is still present and the technical infrastructure can be described as decrepit. The planning approach presented here consists of the integrated delineation and bundling of measures, along with the creation of an adapted database structure and a decision-making process for prioritisation. The form of the resulting implementation plan will depend on the actual costs and duration.

Groundwater quality under stress: contaminants in the Kharaa River basin (Mongolia)

Groundwater quality in Mongolia is increasingly endangered by expanding mining and industrial activities, urbanization and intensified land-use for agriculture. In the framework of the research project Integrated Water Resources Management in Central Asia: Model Region Mongolia (MoMo) project, groundwater and surface water quality has been monitored since 2007 throughout the Kharaa River basin, which includes the second largest city of Mongolia, Darkhan. In order to investigate the potential impacts of human activities, groundwater samples have been collected at 40 locations and were analyzed for heavy metals, electrical conductivity, chloride and boron. The initial characterization of all groundwater bodies in the river basin was an important prerequisite for the assessment of groundwater quality. Our results show impacts especially in the lower and middle reaches of the Kharaa River basin including the city of Darkhan and the smaller towns Khongor, Salkhit, Zuunkharaa and Baruunkharaa. Particularly in Khongor, significantly high values of electrical conductivity, chloride and boron were detected, indicating serious pollution by domestic and industrial wastewater. Furthermore, elevated concentrations of heavy metals, especially arsenic, lead, zinc, nickel, iron and manganese, were found in the vicinity and downstream of mining areas whereby in some cases the maximum contaminant level of the Mongolian drinking water guideline was exceeded. The findings of this study illustrate explicitly the stress on groundwater quality and its vulnerability in the Kharaa River basin. A sustainable water resources management needs to be urgently implemented to avoid potential public health impacts.

Experiences with stakeholder involvement in strategic sanitation planning: a case study of the city of Darkhan, Mongolia

Stakeholder involvement is a prerequisite in urban strategic sanitation planning, particularly in low-income countries. This paper investigates the experiences and lessons learnt in terms of effective stakeholder involvement gained from a case study on strategic sanitation planning in a peri-urban sub-district in the city of Darkhan, Mongolia. Conceptually the Darkhan case study builds on a participatory sanitation planning approach known in the literature as community-led urban environmental sanitation (CLUES) planning. Firstly, a brief introduction to the CLUES approach, its basic principles for effective stakeholder involvement and its adaptation to the Darkhan case study is given. Secondly, two relevant planning steps including the building and testing of pilot facilities are described and assessed in terms of effective stakeholder involvement. It is shown that even if not all basic principles could be fulfilled adequately, the participatory planning framework helped to improve the scientific outputs of the project – mainly the technological research and development – and to smooth the way for further actions towards the sustainable implementation of measures on a larger scale.

Affordability of water supply in Mongolia: empirical lessons for measuring affordability

Affordability of water services is a pressing water policy issue for both the developed and, in particular, for the developing world. Despite its well-known theoretical shortcomings, affordability analysis of water supply has, up to now, been widely based on the ratio of a household's water expenditure to its income, the Conventional Affordability Ratio (CAR). However, in the housing sector, alternative concepts for measuring affordability have been developed, among them being the ‘Potential Affordability Approach’ (PAA) and the ‘Residual Income Approach’ (RIA). Against this background, this paper compares these three prominent affordability measures (CAR, PAA, RIA) on the basis of an empirical case study of a peri-urban, low-income area in the second largest Mongolian city of Darkhan, using household data from a survey conducted in 2009. Thus we gain insight into both the water-related affordability situation of people in Mongolia, checking the World Bank's finding of an absence of water affordability problems in peri-urban areas in the Mongolian capital Ulaanbaatar, as well as into the comparative functionality of different affordability measures. It is shown that affordability problems do occur but have to be distinguished depending on the economic causation. We argue that none of the regarded measures give a satisfyingly contoured notion of affordability properly distinguished from the adjacent problems of poverty and access.

Household needs and demand for improved water supply and sanitation in peri-urban ger areas: the case of Darkhan, Mongolia

The lack of adequate water supply and sanitation services is a major issue related to sustainable development in many parts of the developing world. New strategic planning approaches which directly address users’ needs and demand—often referred to as demand-responsive, community-based or household-centred approaches—are regarded as a crucial step towards improving the situation. This paper investigates household needs and demand for improved water supply and sanitation services in peri-urban, low-income settlements, known as “ger areas”, in the city of Darkhan, Mongolia. The paper is based largely on a household survey conducted in a selected ger area subdistrict in Darkhan. The results reveal a complex picture. Even if the existing situation can be regarded as largely “improved” in terms of the definitions stipulated by the Joint Monitoring Programme for water supply and sanitation, it is shown that there is a need for action nonetheless. The paper also argues that the household survey is a useful method for assessing users’ needs and demand and for meeting the requirements of demand-responsive sanitation planning approaches.