Overburden Material Research Articles

Evaluating Overburden Materials for Haul Road Construction with and Without Cellular Confinement: A Comprehensive Study in Indian Context

Evaluating Overburden Materials for Haul Road Construction with and Without Cellular Confinement: A Comprehensive Study in Indian Context

Investigation of Strength and Long-Term Durability Properties of stabilized Coal Mine Overburden Material for Base and Subbase Layer of Pavement

Investigation of Strength and Long-Term Durability Properties of stabilized Coal Mine Overburden Material for Base and Subbase Layer of Pavement

Optimasi Desain Geometri Lereng Material Old Dump Pada Usaha Penggalian Ulang Pit X PT. Bukit Asam Tbk

In doing slope design, it is necessary to pay attention to slope geometry and soil shear strength. Determination of slope geometry design also considers the balance between height and slope and production benefits. Research was conducted to analyze slope stability through physical and mechanical properties testing, limit equilibrium, and probabilistic Monte Carlo methods. The surface area of the Overburden stripping area in the 2024 RKP design is 8,172.79 m2. The production target is 2,000,000 tons of coal with a volume of overburden material that must be stripped of 29,000,000 BCM and obtained a Stripping Ratio value of 14.5. The results of the evaluation of the overall slope of the Old Dump material with an overall slope height of 66.582 m, a slope width of 447.69 m, an overall slope of 8.32˚ and a bench width of 25 m, a bench height of 6 m with a comparison ratio of 1:3 and a single slope angle of 18.43˚. Then the redesign was carried out and obtained recommendation results of 64.799 m overall slope height, 303.33 m slope width, 13.02˚ overall slope, and 25 m bench width, bench height at elevation 131-110 of 8 m with a comparison ratio of 1:2, single slope 26.57˚ and at elevation 110-50 of 8 m with a comparison ratio of 1:1.5, single slope 33.69˚.

BENCH HIGHT AND SLOPE ANGLE ON LITHIUM ORES OPEN PIT MINES

The fundament of the open pit geometry, both, on metallic and non-metallic mineral raw materials, consists of benches that allow mining operations to be carried out in the contour of the open pit mine. On lithium pit mines, formed benches of a certain height and slope angle, must ensure physical stability of the open mine pit and smooth running of mining work to excavate, load and transport the overburden and mineral resources out of the contour of the lithium open pit mine. The bench height and slope (bank) angle depend on the geotechnical situations, water impact and conditions of utilizing mining mechanization in digging, loading and transporting the overburden and mineral raw material. Key words: lithium, open pit mine, bench height, bench slope angle

Integration of HIRARC and B/C Ratio to Reduce the Number of Accidents in PT. XYZ

PT XYZ is one of the companies engaged in the mining industry. The company has total coal reserves of 5.8 million tons and produces a coal calorific value of 4900 Kcal/kg GAR. PT XYZ uses a 30-ton class dump truck for overburdened transportation activities. Overburden transportation is transporting material from one location or facility to another. The operation of dump trucks has risks that need to be controlled to minimize work accidents. Truck operators have considerable risks, including bumping, hitting, slipping, falling, and pinched. This study aims to identify potential accidents that can occur and propose preventive measures based on the risk level of each possible accident in the operation of dump trucks using the HIRARC method at PT XYZ. Based on the results of the study shows that the potential hazards experienced by dump truck operators include collisions, pinching, slipping, overturning units, backing units when on an incline, buckets crashing into vessels, grazing other units, low back pain, neck pain, herniated nucleus pulposus, fatigue, loss of control, unprotected operators, collapsed and dragged units, reduced control, loss of control, trapped units, buried units, falling into ravines, damaged units. In addition, the risks experienced by dump truck operators are 6 high risks, 7 medium risks, and 9 low risks. From the overall transportation of overburden material, dump truck operators experienced a high risk of 27%, a medium risk of 32%, and a low risk of 41%.

Long-Term Strength and Durability of Cement-Treated Coal Mine Overburden Materials in Subbase and Base Layers of Low-Volume Roads

Long-Term Strength and Durability of Cement-Treated Coal Mine Overburden Materials in Subbase and Base Layers of Low-Volume Roads

Strength, deformation, and environmental impact assessment of cement stabilized mine overburden soil

Mine haul roads are the unpaved roads that are constructed from the overburden materials obtained from the mining operations and are used for the movement of heavily loaded dumpers and trucks. The haul roads constructed from this overburden material shows continuous distress in the form of over ruts, potholes, and shear failures, creating major issues in the movement of dumpers. In the present research study, an experimental investigation was conducted based on mechanistic empirical design to evaluate the strength-deformation characteristics, durability, and environmental emissions of cement stabilized overburden soil of a local mine. The unconfined compression tests were conducted at cement dosages varying from 1 to 6% of dry soil mass and increase in the unconfined compressive strength were examined at different intervals of time until 28 days of the curing period. In the case of static triaxial tests, the enhancement in undrained shear strength and elastic modulus of stabilized specimens was determined in comparison to the untreated specimens, whereas in cyclic triaxial tests, the reduction in permanent deformations and increase in resilient modulus were evaluated under different confining pressures and cyclic deviatoric stresses. An empirical model has been proposed to predict the long-term rutting of overburden under repeated loading. The proposed model is based on the behaviour of various parameters, such as applied cyclic deviatoric stress, number of load repetitions, loading frequencies, and on the permanent deformation characteristic of mine overburden soil. In addition, durability and environmental sustainability aspects of the treatment has also been studied to determine the optimal dose of cement.

Reclamation of derelict mine land by simply growing crops

ABSTRACT Reclaiming derelict mine land is good for the environment, good for public health, and good for agricultural production. Technologies to optimise soil fertility and crop yields with the least time, cost and damage to the environment have been developed in the Nikopol district of Dnipropetrovs’k region which has been extensively strip-mined for manganese and, in some places, restored by replacement of the overburden. Perennial legume-grass mixtures recreate fertile soil, not only in reconstituted chernozem but, also, in raw overburden materials. Different materials respond at different rates but over the longer term (50 years), legume-grass mixtures continue to improve soil physical, chemical and biological attributes. The lessons learned are equally applicable to reclamation of war-torn land.

UTILISATION OF GREEN WASTE FROM MINE OVERBURDEN THROUGH BIO-ELECTROCHEMICAL SYSTEMS

ABSTRACT. Proper management of overburden materials can reduce the environmental impact and increase the benefits of mining activities. It is important to consider the specific composition of the overburden and local needs when selecting the most appropriate recovery method. And while much of the overburden material can be used in construction, reclamation, cement production and more, the green waste problem has not been sufficiently solved. In the present publication, the possibilities of generating energy from the green waste from the overburden through bio-electrochemical systems are investigated. The possibilities of generating energy from grass, wood chips and leaves have been studied. The best results were achieved in grass utilisation, generating a power density of 107,58 mW/m2.

Examining the properties, behaviour in firing and potential application of coal mine overburden for stoneware ceramics

Purpose. A binary mixture of a ceramic body was studied, incorporating overburden from a coal mine site in Bontang, East Kalimantan, Indonesia. This overburden material has been tested for the manufacture of stone-ceramic body. Methods. The initial characterization of overburden materials includes testing the chemical composition by XRF analysis and mineral content by XRD analysis on raw materials and overburden exposed to high temperature. The composition of ceramic specimens is a mixture of 85% overburden material and 15% fine sand. Firing temperatures in the range of 900-1100°C were applied to the ceramic body specimen. Then, ceramic properties, such as physical color, plasticity, shrinkage, water absorption and density were analyzed. Findings. The results show that the ceramic specimen experiences densification when exposed to high temperature in this range, which in turn contributes to low water absorption and high flexural strength. This ultimately results in low water absorption below 1.0% at 1100°C, which is favorable for stoneware type of ceramics. The mechanical properties of specimen at 1000°C is in accordance with stoneware body standard. In addition to this, it is believed to be more energy efficient, since the low firing temperature is sufficient to achieve the stoneware specification. Originality. The binary clay-based ceramic have been tested using coal mine overburden and river sand with a high Fe2O3 content. Together with the presence of alkali oxides and calcium in the raw materials, this can potentially reduce the use of fluxing agent. A comprehensive study has been conducted on the characteristics, firing effect and application of stoneware. Practical implications. Some ceramic prototypes from this result were also made using a rotary technique and heated in this temperature range. Since overburden is generally considered to be backfill material, the selective clay material application for ceramics can provide the potential to stimulate local product innovation by utilizing easily available overburden materials.

Kajian Produktivitas Alat Gali-Muat dan Alat Angkut pada Pengupasan Overburden di PIT TSBC, Tambang Air Laya, PT. Bukit Asam, Tbk.

Production targets are the parameters for whether a mining company is successful or not in carrying out its activities to achieve profits every year, without forgetting occupational safety and health, which are two important factors in the movement of a mining industry. There are so many other factors such as weather factors, human factors, equipment factors and even the roads used by transport equipment that transports overburden materials and coal. By knowing the inhibiting factors and supporting factors to increase productivity and overcome obstacles that occur in the field so that the company's production targets can be achieved and exceed the expected targets. In order for the process of extracting overburden material to be maximized, it is necessary to calculate the required number of loading and conveying equipment, as well as the effective time used in mining activities. Based on this information, the author took the title regarding a study of the productivity of the Komatsu PC 2000 Excavator digging and loading equipment and the Komatsu HD 785-7 Dump Truck transport equipment in overburden stripping at the TSBC Pit, Tambang Air laya, PT. Bukit Asam.

Exploring mechanical and microstructural properties of cement-stabilized coal mine overburden materials

The present research explores the suitability of coal mine overburden (OB) material, as secondary aggregate in the sub-base and/or base layer of low-volume roads. As low-volume roads are expected to have less traffic than other types of roads, weak materials like coal mine OB may effectively be utilised in different layers of the road after stabilisation with cement. In that direction, various strength parameters, namely unconfined compressive strength, flexural strength, flexural modulus, and indirect tensile strength have been evaluated after seven days and 28 days of curing on stabilised samples collected from five different mines in Jharkhand. Subsequently, the results have been validated through the non-destructive test and microstructural analysis. Moreover, correlations have also been established between compressive strength, flexural properties, and tensile properties of cement-treated OB (CTOB) samples, which will be beneficial for field engineers to estimate flexural and tensile properties of CTOB mixes from known compressive strength values.

Analysis of difference in results of overburden production volume using Surpac 6.5.1 software and truck count method at Pit 2 PT. Baturona Adimulya

The overburden production volume at PT Baturona Adimulya was known from two methods of measurement: joint survey activities to produce survey progress data and truck count methods. The total volume of overburden excavation based on the survey results from January until October was 2.415.231 BCM, while the truck count was 2.522.862 BCM, which was known from the daily report of OB removal data from January to October by the surveying division of PT AWU. There is a difference in results every month for both methods. The biggest difference occurred in June at 27.289 BCM, with the total difference in the calculation of overburden volume from January to October at 107.631 BCM. Observations in the field revealed several factors that caused difference between the calculation of the excavation volume based on the survey and the truck count from January–October. Factors that influence the difference from the number difference of 107.631 BCM are double handling, load variation, type of overburden material, the material is still attached to the vessel (1.2182 m3 per trip on the Isuzu giga fvz, 1.2061 m3 per trip on the Cat D400E ADT, 1.0936 m3 per trip), human error, and errors in the implementation of measurement activities.

Operational Management For “Mining Contractors Services Company” In Indonesia

Background - The mining contractor services business that Company will operate focuses on the process of mining overburden material and coal mining products which are carried out in an open pit manner, then the coal products will be hauled or transported to the port of the concession owner. This operational process requires operational costs in accordance with the work according to the contract, Operational costs are very influential in getting a positive profit margin, because this business is what the client or concession owner pays is the rate of $/BCM of Overburden and $/Ton of coal produced. The Company only gets service revenue, not the selling price of the coal. This makes the operational cost factor very significant in maintaining this mining service business costs are very influential in getting a positive profit margin, because this business is what the client or concession owner pays is the rate of $/BCM of Overburden and $/Ton of Coal produced. The Company only gets service revenue, not the selling price of the coal. This makes the operational cost factor very significant in maintaining this mining service business.

Development and evaluation of coal mine waste materials for gainful utilization

Coal mine overburden and thick inseam parting materials found in the lower Gondwana basin are treated as mine wastes. Unused fly ash from coal-fired plants is another waste material. This investigation focused on using these wastes to develop better composite materials. Composite materials of varying compositions with coal mine wastes from 50 to 90% and fly ash from 10 to 50% with 2–6% cement additives were developed and evaluated. Their physical, chemical and geotechnical properties were determined. Ordinary Portland cement strongly influenced the geotechnical parameters. The fly ash content was optimized for unconfined compressive strength (UCS) and California bearing ratio for both mine wastes. Composite materials with 70% overburden, 30% fly ash and 6% cement showed a UCS of 4.01 MPa at 56 days. Composites with 80% inseam parting, 20% fly ash and 6% cement produced 4.90 MPa UCS at 56 days. Linear correlations were observed between fly ash percentage in the two composites and their UCS values. Pearson’s and Spearman’s coefficients produced a high correlation of −0.9 for the composite prepared with parting material. Microstructural analysis showed calcium silicate hydrate gel formation occurring at 28 days. The composites meet the strength criterion for the base and subbase of coal mine haul roads.

Large Scale Trials of Waste Mine Burden Backfilling in Pit Lakes: Impact on Sulphate Content and Suspended Solids in Water

The paper describes the results obtained from a large-scale trial designed to assess the impact of the backfilling of waste mine burden in an exhausted pit on the quality of lake water. The trial aimed at understanding the interaction between groundwater and clay and silty sand soils composing the overburden material. The two main environmental concerns related to the turbidity of the water and the concentration of sulphate ions. Tests were designed to (I) assess the interaction between soil and water; (II) measure the turbidity of water, related to the amount of solid particles in suspension; (III) observe the sedimentation of fine particles; (IV) measure the concentration of sulphate ions during backfilling and water pumping operations; and (V) validate an analytical model for the prediction of sulphate quantity in water. The main results indicated that the basin was capable to retain particles with sizes in the order of diameters that were nearly 10 microns. The water pumping was responsible for a relevant motion of fine particles (diameter less than 2 μm); this effect impacted on the turbidity level observed at the outflow in a relevant way. On the other hand, the test indicated that the estimation of the release of sulphate ions in the water was heavily affected by a proper assumption of the average background values of the concentration of sulphate ions in the water before the dumping activity.

Chemical and biological tracers to identify source and transport pathways of septic system contamination to streams in areas with low permeability soils

Septic systems are widely used in rural areas that lack centralized sewage treatment systems. Incomplete removal of domestic wastewater contaminants in septic systems can lead to leaching of nutrients (P and N), bacteria/viruses, and trace contaminants to surrounding groundwater and surface water. This study focuses on delineating the fate of wastewater contaminants in localities where septic systems are installed in moderate to fine-grained overburden materials to assess potential impacts on groundwater and surface water quality in these settings. Nutrients and a suite of anthropogenic tracers, including host-specific fecal indicator bacteria (bovine- and human-specific Bacteroides), pharmaceutical compounds (caffeine, carbamazepine, gemfibrozil, ibuprofen, naproxen, and sulfamethoxazole), and an artificial sweetener (acesulfame-K), were selected to evaluate differences in transport properties. Surface water samples (n = 103) were collected from streams upstream (US) and downstream (DS) of three rural hamlets up to two times monthly over one year. Results indicate the presence of wastewater indicators in the streams, with DS locations showing significantly elevated concentrations of both chemical and biological anthropogenic tracers. Human-specific Bacteroides, caffeine, and acesulfame-K were consistently observed at elevated concentrations at all DS sites. Nutrients exhibited varied concentrations between US and DS locations at three study sites. The occurrence of human-specific Bacteroides in the surface water samples suggests the presence of preferential flow pathways within the silt/clay overburden. These results demonstrate the advantages of using a combined tracer approach, involving a conservative tracer such as acesulfame-K coupled with the human-specific biological indicator Bacteroides (BacHum), to understand not only impacting sources but also potential transport pathways of septic system contamination to nearby streams. Septic systems may be an underappreciated contaminant source in rural hamlets located in fine-grained overburden materials; although, a distinction of specific nutrient sources (septic systems vs. agriculture) remains challenging.

GROUNDWATER EXPLORATION FOR WATER WELL SITES IN ABATA ASUNKERE COMMUNITY, ILORIN, NIGERIA

In this study, Electrical resistivity investigation was carried out at different sections of Abata Asunkere Community, Ilorin, Nigeria with the aim of evaluating groundwater potential and properties of the aquifers. Geophysical technique adopted in this work were the Vertical Electrical Sounding (VES) and 2-D Electrical Resistivity Tomography (ERT) using Schlumberger array configuration. ERT was established on two profiles at the study area with total distance of 80 m apart with 5 m electrode spacing. Eight (8) VES points were sounded along the established profiles. The results revealed four geo-electric layers which correspond to the topsoil, clayey layer, sandy clay and the last layer to the bedrock in all the VES points sounded. The topsoil has apparent resistivity values ranging from 5 to 437 Ω-m and 0.5 m to 1.7 m while the last layer which is the fractured/fresh basement rock has resistivity ranges of 27 Ω-m to 9800 Ω-m and is characterized by infinite thickness. The curve types obtained are H, QH and HK curve type signatures with the H curve type covering about 60 % of the study area. High potential for groundwater was observed at the northeastern and southern part of the study area. Aquifers in most part of the study areas are relatively shielded from contamination because of high protective capacity of the overburden material. It was hence concluded that, the study area has a promising groundwater potential. Based on these results, groundwater exploration at optimum yield was recommended. Depending on the volume of water available during drilling, the maximum depth of drilling may reach up to 60 m.

Optimasi Konsumsi Fuel Dump Truck Terhadap Pengaruh Grade Jalan Pada Aktivitas Penambangan Pada PT. Pamapersada Nusantara Kecamatan Sangatta Utara Kabupaten Kutai Timur

The grade or slope of the road in a mining activity is certainly unavoidable. In addition to naturally following topographical contours, the shape of the mining pit is carried out from a high elevation leading to the lowest elevation following the slope level and the continuity of the excavation material makes the road should be made sloping. The high or low value of the road grade in addition to affecting the speed and travel time required by the unit, of course, also affects the level of fuel consumption. PT. Pamapersada Nusantara uses a conveyance unit with the HD Komatsu 785-7 type to move overburden material. Based on the results of the analysis, in the loaded condition, grade 2% uses 0.45 liters of fuel, 5% grades 0.77 liters, 6% grades 0.89 liters, 8% grades 1.09 liters and grades . While in the unloaded condition, grade 2% uses 0.19 liters of fuel, 5% grades 0.35 liters, 6% grades 0.4 liters, 8% grades 0.47 liters and 9% grades 0. 52 liters.

The challenges associated with laboratory scale physical modelling of high-plasticity spoil materials

Characterisation of spoil (surface mine overburden) material is essential when investigating geotechnical issues associated with the spoil, e.g., for investigating the stability of pit lakes formed with spoil or spoil-structure interaction for any structures built on the spoil as part of sustainable developments. A significant proportion of spoils found across European countries are classified predominantly as silty clay with significant plasticity index and low permeability. In this paper, the difficulties associated with laboratory testing of highly plastic spoil materials obtained from different post-mining sites within Europe are discussed. The issues associated with small-scale laboratory testing of field spoil samples, development of an equivalent spoil for performing physical modelling tests, and the difficulties of centrifuge tests with spoil models are discussed in detail.