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By Fred D. Fox

INTRODUCTION Approximately two years have elapsed since the first summary of the Grizzly Gulch Tailings Disposal Project was presented (1). Since that time, various physical modifications and additions to the existing treatment system have transpired. Further, Homestake and the entire mining industry have been impacted severely by additional modifications and additions concerning regulatory reform aimed at total disciplinary permitting and hazardous waste management. The following paper summarizes the past accomplishments relating to the Grizzly Gulch Tailings Disposal Project, correlating these accomplishments with future plans that are being developed to comply with regulations and to continue Homestake's commitment to environmental protection. The famous Homestake Gold Mine, located in Lead, South Dakota, has been operating in the Black Hills region for over a century, approximately 12 years before the south half of Dakota Territory was admitted to the Union as the State of South Dakota (2). During the 104 years of operational development, Homestake's Gold Mine, as well as the entire mining industry, have been influenced by numerous governmental regulations dating back to the Refuse Act of 1899 which regulated the deposit of debris from mines and stamp works. The enactment of the National Environmental Policy Act of 1969 may be thought of as the beginning of a long line of unplanned steps to deal with the many concerns of matters pertaining to the environment. Environmental awareness continued into the 1970’s, in which the Clean Air Act, Federal Water Pollution Control Act, Safe Drinking Water Act, Toxic Substances Control Act, and the Resource Conservation and Recovery Act (RCRA), to name a few, surfaced.

Jan 1, 1983

By Chunbao Z, Zhenchuan Z

As known to the international mining sectors, Hunan province, called as ' Nonferrous Native Area ', is the main base of nonferrous metals Pro- duction in China. There are over 194 nonferrous mines in this province, most of them distribute over the basin of Xiangjiang River. The state of management of wastewater in Hunan's nonferrous mines is outlined.The experiences and economic benefit in the management and treatment of wa- stewater in Bofang and Mayang copper mines, and at Shizhuyuan polymeta- llic mine, are mainly introduced. It concludes with measures and recommendations for future management and treatment of wastewater in Hunan's nonferrous mines.

Jan 1, 1988

By E. M. Wilde

Through the USGS's National Coal Availability program, coal resource appraisals have been completed for three 7.5-minute quadrangles (Willow Crossing, Colstrip East, Colstrip SW) in the Powder River Basin area of southeastern Montana. Available coal reserves (original reserves minus tonnages affected by current restrictions) vary from 44 to 70 percent of the original reserves. Major restrictions impacting each area also vary. In each area, one or two beds contain most of the reserves, but up to eleven beds contain available coal. The main beds in completed studies are the Knobloch, Rosebud, Sawyer and Flowers-Goodale. Three additional areas (six 7.5-minute quadrangles) are in preparation.

Jan 1, 2001

By Christie A. Callender, Harry M. Dahl

The Hobson uranium deposit is located in Karnes County, Texas, along the prominent south Texas uranium trend. The uranium mineralization occurs in the Deweesville Sandstone of the Whitsett Formation of the Eocene Jackson Group. The host rock is a friable, fine-grained, well-sorted, highly porous and permeable sandstone interpreted to be an ancient beach deposit. The sandstone contains significant volcanic constituents and ranges in composition from arkosic to tuffaceous. Locally, the host sandstone contains hard, dense opal cement. Bentonitic shales underlie and overlie the mineralized sandstone unit. Geometrically, the Hobson uranium-bearing zone resembles an elongated roll front type deposit. Chemical uranium values compared with gamma ray equivalent uranium values indicate that the uranium has been dissolved from the updip side and precipitated on the down- dip side of the roll front. Details of the uranium mineralization were studied using thin section microscopy, autoradiography, x-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) techniques. The uranium mineralization occurs in the pores of the sandstone, as grain coatings and as replacement of sand-size and smaller grains. It is commonly associated with pyrite and other opaque minerals. Other favored hosts for uranium (other than pore openings) appear to be clay aggregates, altered rock and glass fragments, and carbonaceous plant debris. Aggregates of coffinite were identified by XRD and SEM/EDS analyses. Some uranium mineralization also appears to be dispersed and is postulated to be adsorbed on the clay and carbonaceous matter.

Jan 1, 1985

The Kaltails Project is situated close to the city of Kalgoorlie-Boulder in Western Australia. Located on the south-eastern fringe of the Golden Mile, Kaltails has been in operation since June 1989. The tailings forming the reserve for Kaltails have been derived from 100 years of underground mining on the Golden Mile, but, some of the re.;erve has been retreated in the past. A map of the tailings reserves and treatment plant site is presented as Figure 1. The gold project is a joint venture between Poseidon 90 per cent and Gold Corporation (ten per cent) and is managed by Poseidon Gold Kaltails.

Jan 1, 1992

By Fejes G

An integral part of the Brisbane Suburban Railway Electrification involved the relining, refurbishment and track lowering in the Roma Street, Brunswick Street and Gloucester Street double track tunnels. The design and the construction procedures had to satisfy the Queensland Railways electrification clearance and track standards and the requirements of maintaining track services through the tunnels during work. Refurbishing of the tunnel linings was carried out to extend the life of the tunnels.

Jan 1, 1981

By Robert Strachanm

The East Kootenay coal-field, situated close to the boundary between the provinces of Alberta and British Columbia, is composed of four small areas locally called the Crow's Nest Pass, the Upper Elk, the Flathead and Crown Mountain, and comprises an area of about 3 78 square miles. From eleven to twenty-five seams have been exposed of two feet and over in thickness, with a total thickness of about 200 feet of coal, and reckoning about one hundred feet to be workable, gives an estimate of coal available of about thirty-seven billion tons. The coal is a high-grade bituminous, occasionally tending towards anthracite, and the majority of the seams furnish a. very good quality of coking coal as well as an excellent steam coal. The coal-field is found in the mountain ranges in long narrow strips. The age of the fonnation and the thickness of the covering beds have had considerable influence on the character of the coal, and lateral pressure and disturbances in the process of mountain-building have wrought great changes. With such an abundance of coal, it has been a disappointment that the East Kootenay field has not figured larger industrially. So far only one portion of the coal-field has been utilized. This is the Crow's Nest, where, in 1898, the Crow's Nest Pass Coal Company commenced development. Access to the coal seams was easily obtained, the mountain creeks having eroded away the covering, and mines were driven into the coal seams. In that year about ten thousand tons of coal were produced from the mine at Coal Creek.

Jan 1, 1924

By Ed Van Eeckhout

As part of a U.S. Bureau of Mines-sponsored project on the utilization of "stiff" backfill to minimize potential rock burst hazards, a finite element study was undertaken to predict stresses and displacements around a stope mined up from the 5400 level of the Sunshine mine, Kellogg, Idaho. This stope was to be backfilled using a high-modulus fill. In preparation for that configuration, certain instrumentation was installed near the 5400 level to monitor stress changes. Due to untenable economics, only 2 cuts of the stope were ever made. This paper presents the results of the instrument readings taken during the first cut and compares them with the numerical predictions, as well as presents the modeling results of closure and fill stresses in the stope if it had been mined.

Jan 1, 1984

By D. A. Bird

Water chemistry data were used to identify the sources of ground-water and surface-water inflow to the IOZ block cave mine. Water samples were collected to obtain vertical and lateral hydrochemical profiles within different levels of the underground workings. Water chemistry data were evaluated in conjunction with geologic and structural information to define controls on locations of ground-water inflows, and to select targets for drilling and interception of water. Drilling has intercepted water-producing zones that were previously unidentified through mapping and drilling. The program has resulted in a reduction in water inflows to the block cave area.

Jan 1, 1998

By A B. Christie, R Barker

Recent studies carried out to support the development of a strategy for the New Zealand mineral industry by the NZ Minerals Industry Association have included investigations of mineral potential, and the development of scenarios for realising this countryÆs mineral potential by 2010. New economic research is applying a general equilibrium model to quantify the opportunity cost of this potential. The model analyses separately four categories of land (private land and three categories of Crown land) and identifies four distinct mineral classes û precious metals, industrial minerals, coal and aggregate. It investigates the economic effect of the increased availability of mineral resources on the mining industry itself, on other industry sectors and on the NZ economy generally, including its impact on unemployment, GDP and household welfare.The analyses suggest that increases in the level of GDP of between 1.9 per cent and 3.4 per cent may be obtained by utilising New ZealandÆs mineral wealth to varying degrees. The mineral industry sectors are significant beneficiaries under all scenarios; mineral output increases by between two and five times its current level. However, the flow-on effects to the rest of the economy, and to households, are also significant. The analyses show that household income, adjusted for changes in consumer prices, can be expected to increase by between 1.6 per cent and 2.7 per cent. This results largely from increased employment.

Jan 1, 2002

By Marcos Vinícios de Souza

Os aços carbono são materiais metálicos muito importantes na fabricação de peças para a indústria metal-mecânica. Parafusos, hastes, eixos, pistões, engrenagens são fabricados a partir desse tipo de aço, mais especificamente do aço SAE1040. O objetivo desse trabalho foi de avaliar a influência da presença de 0,2% em massa de cromo nas propriedades mecânicas e metalúrgicas de um aço com 0,4% em massa de carbono. A liga padrão SAE1040 e esta liga modificada com cromo foram submetidas a tratamentos térmicos de normalização, recozimento, têmpera e revenimento, e comparadas às durezas e microdurezas das diferentes amostras entre si. Os resultados obtidos evidenciaram que a adição de cromo é um método eficiente quando se deseja aumentar a resistência de um material. Observou-se que os valores de dureza e microdureza para o aço com a adição de cromo apresentaram-se maiores em relação ao aço padrão, como consequência das microestruturas obtidas, principalmente após têmpera e revenimento. A adição de 0,2% em massa de cromo no aço carbono influiu na melhora das propriedades mecânicas do aço tornando-o mais interessante na fabricação de peças para a indústria metal-mecânica.

Aug 8, 2018

By Camila Luzia Lira Duarte

O processo de pelotização utiliza o combustível sólido com intuito de gerar energia térmica que será transferida para a pelota de forma a alcançar uma queima uniforme. Na usina de Vargem Grande normalmente o antracito é utilizado como combustível sólido. Com objetivo de testar diferentes fontes de combustível sólido, um teste industrial de com coque breeze substituindo o antracito foi realizado. Como o coque breeze possui menor teor de matéria volátil, cinzas ei maior teor de carbono fixo, o consumo de gás natural no forno pôde ser reduzido. Além disto, o coque breeze apresentou um perfil de combustão mais favorável à qualidade da pelota resultando em ganho nos resultados de compressão. Dessa forma, a viabilidade econômica e operacional da substituição do antracito pelo coque breeze foi positiva.

Aug 17, 2017

By Arash Saeidi Rashk Olia, Dunja Perić

The increasing demand for renewable energy has attracted attention to energy geostructures as means of extracting clean geothermal energy from the ground. To further advance the understanding of soilstructure interaction in energy piles analytical solutions considering the self-weight of the pile were derived. These solutions were then incorporated in recently-derived thermomechanical weightless solutions to provide comprehensive analytical solutions for axial displacement, strain and stress in single energy piles. This was accomplished by comparing responses of energy pile under different loading scenarios that reflect presence and absence of the self-weight. Results of mechanics-based analysis revealed that the self-weight of energy piles embedded in stiff soils has no significant contribution to displacement, strain and stress that develop under thermo-mechanical loads. Overall, the significance of the self-weight contribution depends on the magnitude of thermal load as well as the soil-pile interface stiffness. The stiffness of end restraints imposed to the pile head and tip were also found to play an important role in contribution of self-weight in induced thermomechanical stresses in energy piles.

Oct 1, 2022

By Aaron L. Sacks, David R. Good, Srinivas Yennamanda, Joseph K. Carey

Construction of Parcels 6 and 7, the second phase of The Wharf, began in 2019 and geotechnical construction was completed by December 2020. The overall project consisted of horizontal site, parks, and office buildings. The Wharf’s Phase 2 development includes approximately 1.2 million ft2 (110,000 m2) of above-grade construction including five multi-story, mixed-use buildings constructed over up to three levels of underground parking. The site is located between the WMATA Green Line Tunnels to the north and the Washington Channel to the south; it is bisected by a 108-in. (2740-mm) diameter DC Water outfall pipe. This arrangement, along with very difficult ground conditions, created challenges in the geotechnical design and construction. The support of excavation for this complex project required several different methodologies, including sheet piles, soldier piles, displacement piles, tiebacks, deep foundation anchors, jet grouting, and internal bracing with multi-tier rakers. Ground improvement was also required for support of spread footings in soft soils over the garage footprint. Underpinning of the active 108-in. (2740-mm) diameter DC Water outfall pipe running on a north/south alignment through the center of the site between the two garage structures was also performed. Since portions of the support of excavation are below the groundwater table, an extensive pre-excavation dewatering program was necessary and was separate from the foundation package. On the north side of the project, support of excavation (SOE) was required on a curved alignment, offset approximately 10 ft (3 m) from the outbound Green Line tunnel. Due to the proximity of the tunnel, a stiff, near-zero displacement wall was required. A portion of the buildings extend over the tunnels, imparting load to the tunnels to approximately restore original overburden loads excavated for the basement space. The building foundation is a 3 to 4-ft (0.9 to 1.2-m) thick mat slab anchored into the Potomac clay formation. Continuous movement monitoring of the tunnels was performed by an automated system. This paper describes the design and construction of the SOE and foundations for this high-profile project, which required collaboration between the Owner, Engineer, Construction Manager, and Specialty Geotechnical Contractor to solve many challenges.

Oct 1, 2022

By Rangaswamy. K, Naga Sivaji

A stone column is one of the most commonly employed methods of ground improvement techniques. This method used to increase the strength, decrease the compressibility of loose granular and finegrained soils. Also, it accelerates the consolidation in clays and reduces the liquefaction potential of sands and silt soils. In general, the stone column contains 15 to 75mm stone aggregates. In reality, it is not easy to avail the natural stone aggregates due to unavailability in locally nearby places. Present work aims to replace the stones partially or entirely by scrap tyre chips as an alternative material. The utilisation of recycled tyre chips in ground improvement is an environmentally friendly solution and avoid the disposal of tyre chip waste in large pits. Model tests conducted on marine clay with encased end bearing stone columns (ESC) constructed with a mixture of stone aggregate and tyre chips with sizes 4.75 to 10mm. The column diameter is 75 mm, L/d ratio maintained to 5.3. Non-woven geotextile wrapped encased stone column has introduced in the soft marine clay model. Encasement prevents the lateral squeezing of aggregates into the surrounding clay and protects the drainage function of the stone column. A set of load-settlement tests were conducted on both the clay model and clay model treated with the stones-tyre chips column. The model was loaded by the tri-axial loading frame. Shear strength parameters of stones and tyre chips were determined by large size direct shear tests. Model test results are concluding that the load-carrying capacity of the clay is improved significantly after installing the stone column in it. The encasement increases the load-carrying capacity and stiffness of the ordinary stone column. It is also proved that the stone aggregate could be replaced partially by tyre chips up to 60% without a significant reduction in its performance.

Nov 1, 2022

By Nick M. Withers, Suthagarann Visvalingam, Cillian Mc Colgan

The level crossings removal project in Victoria is removing 75 level crossings across Melbourne to improve safety by separating trains from traffic, with other benefits such as reduced congestion, an upgraded road network, connected communities and support of urban regeneration. The level crossing at Station Street in Carrum forms part of the scope being delivered by the Southern Program Alliance (SPA), which is delivering level crossing removal works associated with the Frankston Train Line. At Station Street, a rail viaduct consisting of 19 spans and totalling approximately 545 m in length is under construction to remove the former level crossing. The viaduct consists of two parallel reinforced concrete Utrough girders and steel trough girders, one for each rail line. The foundations of the rail viaduct are founded on groups of Continuous Flight Auger (CFA) piles. The characterisation of geological units encountered at Carrum for the foundation design has been based on insitu testing and interpretation of test results from high strain dynamic pile testing (PDA) and Case Pile Wave Analysis Program (CAPWAP) from the Seaford Road Bridge, located approximately three kilometres South of Carrum, in similar ground conditions. By conducting pile load-deformation analyses based on pile testing significant savings were made for the client compared to the original design which was based on more traditional empirical correlations. This paper discusses the pile design methodology adopted using pile test data for this viaduct foundation. The results of this assessment are also compared to existing empirical correlations, and the limitations are discussed. The performance of the adopted pile design methodology using pile test data at Carrum rail viaduct is also discussed.

Nov 1, 2022

By Evan J. Owen, Virginia T. McLemore

Rare earth elements (REE) and critical minerals are increasingly becoming more important in our technological society and are used in many of our electronic devices (such as cell phones, computer monitors, wind turbines, etc.), batteries, and magnets. Measuring REE and critical minerals in ashed coal approximates the REE and critical minerals in the fly or bottom ash remaining after coal is burned at a power plant, where REE and other critical minerals could be leached. In New Mexico, there are 26 coal fields in Late Cretaceous rocks in the San Juan and Raton Basins. These rocks are being characterized as part of the DOE’s CORE-CM (Carbon Ore, Rare Earth, and Critical Minerals) program. Higher concentrations of REE (as much as 2103 ppm total REE) are found locally in ashed coals from the basins. More chemical and mineralogical analyses are required to fully understand the distribution and origin of REE in these deposits. As the demand for REE increases because of increased need and short supplies, the dollar value per ton of ore rises, enhancing deposit economics, perhaps even from coal.

Feb 1, 2025

By Y. T. M. Ocsa, V. O. Tenorio

This research is the result of a geotechnical study carried out in a natural slope in an Open Pit mine in Southern Peru, highlighting earthquakes as an important cause of instability within the case study presented. This leads to analyze the stability of a slope, according to the safety factor and thus consider a future construction in its environment according to the identified requirements. There are known disasters at national and international level that involve human lives because of the lack of analysis of slope stability conditions, which based on the results will allow to control and to take adequate corrective measures. These mass movements are classified whether they are soils or rocks, considering the mechanism and type of rupture, as well as the presence of water, the speed and magnitude of the movement. The movement problems are due to factors of inherent nature and constitute a reason to perform a calculation study to analyze and estimate the safety factor of each of the evaluated cases

Mar 2, 2022

By Anderson da Cunha Meireles, Pedro Garcia, Ernst Young, Leandro Coelho, Carlos Eduardo Soares Feliciano, Key Fonseca de Lima

Rock blasting is a crucial technique employed in mining construction and quarrying industries to fragment large rocks into smaller, more manageable pieces. However, it often generates ground vibrations that can pose significant challenges. This study explores the application of Conformal Prediction (CP) in the context of rock blasting to develop predictive models that estimate blasting-induced vibrations and quantify the associated uncertainties. Various machine learning models were integrated within the CP framework using MAPIE and CREPES libraries. The results demonstrated the effectiveness of CP in providing statistically reliable prediction intervals, making it particularly useful for applications where the stakes of underestimating uncertainty can be high.

Jan 21, 2025

By Carlos Alvarado, Hernan Narea, Jhon Silva, Bryan Townsend, Katherine Gil, Brayan Caceres, Felipe Pontanilla

With the promising development of new technologies, automation in Drill and Blasting (D&B) is on the horizon. The data generated in all D&B activities, which is currently segregated, can be linked to become information and carry a logical meaning. This information can be used to identify critical activities and make decisions regarding corrective measures to accomplish the goals of D&B. Minera Caserones, supporting Alert2Gain (A2G), and Dyno Nobel, has been working on the development of a quality assurance and quality control (QAQC), system for the mine involving all D&B activities. The main variables in the model for D&B include data from the geology of the deposit, drilling, explosive products, and material loading, among others. To create the model, the mine is divided into blasting polygons. Those polygons are part of a block model. The block model is assembled following different rules, such as: • Block sizes of 4m x 4m x 15m, • Classification of the blocks to a particular blasting polygon using a geospatial intersection algorithm, • Algorithms connect all the pieces of data automatically with the minimum of human intervention and populate the block model, Because measuring data for each block is impossible, another set of rules and algorithms completes the model. Dyno Nobel generates an essential set of data for the QAQC system. Explosive truck loading rates and explosive products, among other data, are also included in the system. The system autogenerates reports every hour, and a summary of the results of each mining day (a mining shift of 12 hours) is distributed by email to all responsible persons to identify the critical tasks and then to make the proper adjustments to accomplish the goals of D&B. The information is updated every hour and available through a dashboard for easy and straightforward interpretation. This paper explains the conceptual details of the QAQC system implemented in Minera Caserones, how the data is aggregated automatically from the different sources, shows examples of the type of information in the dashboard, and presents a successful case where a deviation was detected, and the corrective measures that were implemented to keep the performance of the D&B activity. The paper finally discusses the next steps toward an autonomous D&B system based on new AI technologies, with minimum human intervention.

Jan 21, 2025