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By J. Marbeau

In this paper, a geostatistical study of the North Butte roll type uranium deposit is presented. The geostatistical procedure applied takes into account the varying direction of the roll front for reserves calculations. For variogram calculation, the roll front is unfolded thereby allowing estimation of the variogram in directions parallel to and perpendicular to the roll front. Variograms calculated in unfolded space show strong directional anisotropies consistent with the anticipated configuration of the deposit.

Jan 1, 1991

The removal of tritium from tritiated water (-0.5 µCiIL) was studied by metallothermic reduction using aluminum. The influence of the three variables namely the aluminum powder amount, the NaOH concentration and the reaction time has been studied on the tritium activity reduction. The experimental results and statistical analysis showed that more than 85% of tritium can be removed from the tritiated water. Further work on the tritium recovery as well as efforts to totally decontaminate water by incorporating a cryogenic concept is currently pursued.

Jan 1, 1998

By T. J. Fenner

Surface and underground mining operations are often hindered by unknown tunnels and stopes and the precise locations of adjacent workings. Mine safety and planning are adversely affected especially in previously undermined areas where historical records are incomplete or non-existent. The results of several Ground Penetrating Radar (GPR) studies for the detection of known mine tunnels in underground coal; salt, and gold mines are presented. A case study to locate unknown, abandoned mine workings at a surface gold mine successfully located all workings to a depth of 11 meters.

Jan 1, 1992

By Karl J. Ellefsen

A geophysical investigation can provide valuable geologic information needed to characterize sand-and- gravel deposits and can be an attractive complement to more common characterization methods such as drilling. Although such investigations have been conducted already, a comparison of the different geophysical methods used in these investigations apparently has never been done. For this reason, a study was initiated by the Mineral Resources Program of the U.S. Geological Survey to determine the advantages and the limitations of different geophysical methods when used to evaluate alluvial sand-and-gravel deposits. The study is focused on those geophysical methods that are commonly available, because these are most likely to be used by industry. Furthermore, the study is focused on surface geophysical methods. Heretofore, four different methods have been evaluated. Three of the four methods-time-domain electro-magnetic (TEM) soundings, frequency-domain electro-magnetic profiling, DC-resistivity soundings-are similar in that they all measure the electrical resistivity of the ground with depth. Ground-penetrating radar, however, maps changes in the dielectric permittivity and for the electrical resistivity with depth. For all, four methods, the objective is to relate the measured physical quantity to the stratigraphy of the alluvial sediments.

Jan 1, 1999

By Y. C. Guan

In an attempt to replace the traditional cyanide process of extracting gold, a new technology using ammoniacal solutions has been developed. In this study, the electrochemical behavior of gold in ammoniacal solutions at temperatures above 100°C has been investigated. An electrochemical cell in an autoclave has been introduced to carry out this study. The system consists of a gold working electrode, a platinum counter electrode, and an external saturated calomel electrode (SCE) which is connected to the autoclave system through a Birch wood plug. Techniques used in this study included potentiodynamic polarization, galvanostatic polarization, cyclic voltammetry, and Tafel polarization. The electrochemical reaction mechanisms governing the dissolution process are presented.

Jan 1, 1996

By N. R. Billette

In 1982 and 1983, a study was undertaken to analyse the applicability of Elbrond?s analytical model to suit the needs of Lake Asbestos of Quebec in their computerized open pit planning and scheduling strategy. The immediate goal was the assessment of the optimal allocation of trucks and the determination of the extra cost of in-pit blending. Data from 45 tonne trucks was used to estimate the mine capacity based on a fixed assignment policy. The tonnage yielded by the analytical model was compared with the results of a simulation program. Another point that the study high- lighted was the definition of efficiency parameters for the haulage system: shovels-trucks-crusher. The efficiency, both of the utilization of financial resources and of the operations, for the overall system reaches optimal values in very precise conditions for the number of pieces of equipment in operation. Such a parameter is proposed as a standard for the definition of an optimal number of trucks and shovels in operation. Deviations from this optimum do occur in a well-planned system for qualitative goals. These can then be quantified in terms of costs to the mining company.

Jan 1, 1986

By Cuthbert Musingwini, Adeodatus S. Nhleko, Mahlomola I. Mabala

Optimization of a three-dimensional (3D) underground stope layout is complex given the number of variables and constraints to consider, such as the stope size. Determination of the appropriate stope size in stope layout optimization problems is a complex process that must consider several factors including placement of infrastructure and development, production scheduling, and equipment selection. An inappropriate stope layout can result in unrealistic expectations for a production schedule, consequently negatively affecting the derived economic value. Therefore, this paper used a dual interchange algorithm (DIA) to evaluate the effect of stope size on the stope layout economic value (SLEV) for a synthetic Platreef mineral deposit planned for extraction using sublevel open-stoping. The results showed that generally as the stope size increases, the SLEV decreases. This aligns with practical mining because larger stope sizes have a higher chance of incurring more dilution which reduces economic value, while smaller stope sizes enable more flexible extraction where unprofitable blocks can be left unmined as waste, thus increasing the derived SLEV.

Jun 25, 2023

By A. Santha Ram

The Indian Mining sector is subjected to a number of trends including call for global transition towards the route to sustainable development. Several regulations were enacted by the Government departments, from time to time, in order to identify the problems faced by the mining industry, including small-scale mining operations and to suggest appropriate mitigation measures in the form of environmental standards and certifications. During this process, a pursuit of sustainable development is regarded as an important area responding to socio-economic conditions, priorities and thus guides eventually corporate policies and practices. Thus, there is a need to formulate strategies for sustainable development. Based on these strategies some environmental indicators were developed in order to track down the progress and to evaluate its success. A case study pertaining to a group of iron ore mines in North Goa and Chromite mines in Sukinda, Orissa was selected for this study. Base line environmental data has been generated in the respective study sites. A core set of environmental indicators monitoring environmental progress based on the P-S-R model pioneered by OECD is linked with indicators for assessing the integration of environmental concerns.

Jan 1, 2003

By Walter R. Lawrence

Newmont Gold Company, formerly Carlin Gold Mining Company, is a publicly owned corporation, 95% owned by Newmont Mining Corporation. Newmont Gold Company has operated gold recovery operations North of Carlin, Nevada, since 1965. Development of the Gold Quarry ore body, 19 kilometers south of the original mine, resulted in the decision to construct gold recovery and ancillary facilities in what is referred to as the Southern Area. Plant No. 2, located 11 kilometers North of Carlin, Nevada, was designed to treat 6350 tonnes per day of oxidized gold bearing ore assaying 2.5 grams per tonne of Au at an average recovery of 87%. Flowsheet development conducted by Newmont personnel resulted in the decision to construct a carbon-in-pulp recovery circuit preceded by two-stage grinding, Detailed engineering was done at Toronto by Bechtel of Canada beginning on January 1, 1984. Actual construction began on March 1, 1984, and was completed in June, 1985. First feed was run on June 22, 1985.

Jan 1, 1987

By Y. C. Guan

The leaching kinetics of chalcopyrite in ammonium iodide solutions with iodine has been studied using rotating disc. The variables studied J include the concentrations of lixiviants, rotation speed, pH of the solution, reaction temperature, and reaction product layer. The leaching rate was found to be independent with the disc rotating speed. The apparent activation energy was measured to be about 50 kJ/mole from 15°C to 35°C, and 30.3 kJ/mole from 35°C to 60°C. Experimental findings were described by a kinetic model, and the overall rate was found to be: (formula)

Jan 1, 1997

By L. Meier, M. Dennis, J. Schieffer, K. Murray

"INTRODUCTION Contrary to popular belief, Arizona State Trust land is not public land. All uses of the land must benefit the Trust, a fact that is considered with the review of each application received for sale, lease, or permit. This includes applications for activities ranging from commercial development to recreation. In 1863, the Territory of Arizona was established by an act of Congress. This act reserved sections 16 and 36 in each township to be held in trust for the benefit of the common schools. Later, the Enabling Act of 1910 allowed the Territory of Arizona to prepare for statehood. This act reserved the additional sections 2 and 32 of each township for the common schools and granted another 2,350,000 acres to be held in trust for other beneficiaries. In all, Congress granted the State of Arizona almost 11 million acres. The State was to manage those lands and maximize revenue for 13 separate beneficiaries. To meet this mandate, the State established the Arizona State Land Department (ASLD) in 1915. During fiscal year 2015, the ASLD contributed $136 million to the permanent fund, bringing the total value to over $5.1 billion, through the sale and leasing of the land and natural products which includes minerals. The current inventory of State Trust lands includes 9.2 million acres representing about 12.7% of the State.The ASLD Minerals Section manages the exploration, development, and leasing of mineral products on State Trust land. We are not a regulatory agency, but a department guided by our fiduciary responsibilities to the Trust. Our mineral programs include: Exploration Permits, Mineral Leases, Mineral Material Leases, Geothermal Leases, Oil & Gas Leases, and Special Land Use Permits. INDUSTRIAL MINERALS ON ARIZONA STATE TRUST LAND Industrial minerals fall under the category of either Mineral or Mineral Materials Leases. Common industrial minerals found on Arizona State Trust land include potash, limestone, gypsum, salt, specialty clays, zeolites, crushed stone, and sand and gravel."

Jan 1, 2016

By Scott O’Brien, Richard Williams, Camilo I. Mejias, Elias Godoy, Javier Sierra

High-rate thickeners play a critical role in tailings management by enhancing water recovery and increasing solids concentration. However, these units face operational instability due to fluctuations in feed solids, flow rate, and flocculant response typically managed in manual mode with delayed corrective actions. This work presents an adaptive automatic control algorithm designed for dynamic thickening environments. The algorithm integrates real-time measurements of feed density, rake torque, bed level, and turbidity (overflow), optimizing the underflow slurry density while minimizing suspended solids in the overflow. The proposed control strategy is modular, simple, scalable, and applicable to both existing and new thickening systems, offering a robust alternative to manual operation in increasingly demanding metallurgical environments.

Feb 22, 2026

By William G. Pariseau

Safety of mine ramps begins with an analysis of stress that almost certainly must be done numerically to take into account ramp geometry, route geology, rock properties, and pre-ramp stresses. The popular finite element method serves analysis purposes quite well. As a practical matter several obstacles to implementation need to be addressed including collection of rock and joint properties along the proposed ramp route, selection of ramp type, and specification of cross-section shape, size, and route grade. Additionally, stresses along the proposed route must be specified, preferably from in situ measurements. One need not be an expert in numerical methods to proceed to ramp design, although a background in mechanics of materials and rock mechanics is essential, and a first course in numerical methods is quite helpful. The necessary software is easily brought to the design task, more accurately, to the task of design evaluation. This software also addresses other important mine design problems including design of safe (1) main entries in stratified ground, (2) barrier pillars, (3) bleeder entries, (4) inter-panel barrier pillars, (5) room and pillar mines, (6) shafts, and (7) “tunnels” (Pariseau 2022).

Feb 1, 2024

By C. E. Jordan

Direct digestion of phosphate ores by the acid-alcohol method offers improved leaching selectivity for the exclusion of iron and aluminum in the product acid. The leaching kinetics of this process will have a major role in the eventual application of this technology. The Bureau of Mines investigated apatite dissolution to determine the reaction rate and mechanisms of the leaching kinetics. The dissolution kinetics were monitored on various sized fractions of pure apatite. The "shrinking-core" kinetics model was applied to the data to determine the rate controlling mechanisms. For each size fraction, the initial reaction rate was controlled by the dissolution reaction. After an hour the dissolution rate slowed indicating a diffusion controlled reaction caused by the formation of calcium sulfate hemi-hydrate coating on each particle. For complete dissolution of the apatite, the phosphate rock should be ground to near 10 µ m size.

Jan 1, 1993

By K. A. Natarajan, S. Usha Padukone

"An industrial waste liquor having high sulfate concentrations was subjected to biological treatment using the sulfate-reducing bacteria (SRB) Desulfovibrio desulfuricans. Toxicity levels of different sulfate, cobalt and nickel concentrations toward growth of the SRB with respect to biological sulfate reduction kinetics was initially established. Optimum sulfate concentration to promote SRB growth amounted to 0.8 - 1 g/L. The strain of D. desulfuricans used in this study initially tolerated up to 4 -5 g/L of sulfate or 50 mg/L of cobalt and nickel, while its tolerance could be further enhanced through adaptation by serial subculturing in the presence of increasing concentrations of sulfate, cobalt and nickel. From the waste liquor, more than 70% of sulfate and 95% of cobalt and nickel could be precipitated as sulfides, using a preadapted strain of D. desulfuricans. Probable mechanisms involving biological sulfide precipitation and metal adsorption onto precipitates and bacterial cells are discussed.IntroductionIndustrial effluents from hydrometallurgical and mineral processing operations often contain high sulfate and metal concentrations posing significant disposal problems, which require urgent solution to avoid serious environmental contamination. In such waste liquors, sulfate and heavy metals such as cobalt, nickel, zinc and iron originate from the chemical or biological oxidation of exposed sulfide minerals. Reduction of sulfate and precipitation of toxic metal ions from industrial wastes is essential from the viewpoint of environmentally acceptable waste disposal and recovery of associated strategic metals.Many of these heavy metals are essential for metabolic activity of bacterial cells at low levels. But they exert toxic effects at concentrations encountered in polluted water. Removal of toxic metals through biological reduction of sulfates from industrial waste waters have been practiced for several decades. Metal remediation through common physicochemical techniques such as oxidation-reduction, chemical precipitation, filtration, electrochemical treatment, evaporation, ion exchange and reverse osmosis processes is expensive and not suitable in the case of voluminous effluents containing complexing organic matter and low metal concentrations. Further, strong and contaminating reagents are used for desorption, resulting in toxic sludge and secondary environmental pollution. Biotechnological approaches can be more efficient and cost effective for detoxification of such effluents. Biotreatment/ bioremoval offers several advantages over conventional chemical and physical treatment technologies, especially for diluted and mixed contaminants. Biological detoxification, which involves the use of microbes to detoxify and degrade environmental contaminants, has received increasing attention in recent years (Iwamoto and Nasu, 2001). In addition, valuable metals can be recovered from metal sulfide sludge (Boonstra et al., 1999)."

Jan 1, 2015

By H. B. Charmbury

The acid mine drainage problem in Pennsylvania is of continuing and growing interest to the coal mining industry, the state government and the citizenry at large. Approximately one-third of the total volume of mine drainage presently polluting the streams of the Commonwealth originates from active coal operations and two-thirds come from ?abandoned mine discharges.? For this reason the Pennsylvania Department of Mines and Mineral Industries has mounted a significant research and action program seeking solutions to this two-fold problem. The Coal Research Board of the Department has sponsored a wide variety of research projects in an effort to study the treatment of acidic and highly ferruginous mine waters. A review of the published literature on the treatment of mine waters indicated that many laboratory and theoretical studies had been undertaken on various aspects of the coal mine drainage problem, but little applied, developmental, or engineering study had been undertaken. In January of 1964 the Board commenced a rigorous program using state and industry funds in an effort to find a ?least cost? solution or solutions to this vexing problem.

Jan 1, 1967

By M. E. Breitrick

Newmont Gold Company began full production in early 1995 at the Carlin East underground mine. The mine is currently producing at the rate of 900 tpd (1.000 stpd). for an annual production of 150.000 ounces. Approximately one hundred twenty five hourly and salary personnel are employed at the project for the estimated six-year mine life. Two mining methods are currently utilized at the mine. Longhole stoping with cemented backfill accounts for 70% of the total mine production. Conventional underhand drift and cemented fill accounts for the balance of the daily tonnage. In December 1996. Newmont purchased a new AC-Eickhoff ET-210 Roadheader. The machine went into service in mid-June of 1997 and is used in both longhole stope topcut development and cut and fill production at a rate of 225 tpd (250 stpd). The Carlin East mine is operated by Newmont Gold Company. The mine is one of four underground gold mines in production in northeastern Nevada owned by Newmont Gold.

Jan 1, 1998

By W. R. Hibbard

Emerging from discussions of U.S. energy policy: from the Project Independence Blueprint; from President Ford's statements to Congress; and from several independent appraisals of the situation; there is a clear objective to achieve an appropriate balance of supply and demand in the near term future (1) by developing more efficient ways of using energy and (2) by extending domestic sources of energy. More specifically, the strategy for achieving this goal has three parts (1) Conservation of energy through greater efficiencies in automobiles, appliances, lighting, heating, and industrial processes. (2) Increased domestic production of oil and gas through new sources such as the outer continental shelf and new efficiencies such as tertiary recovery. (3) Substitution of coal and uranium for oil and gas in utility power plants and industrial heating. The goal of energy research and development is to help achieve these goals and to help minimize the economic, environmental and social impact of our shift from imported energy to domestic sources. The focus of this paper is the implications of the expanded use of coal, and the research and development which may help achieve the above goals in so far as coal is concerned.

Jan 1, 1975

"Mining of ore bodies that are located at great depths enforces long distances to move the excavated rock masses to the surface. The excavated rock mass contains not only ore that can be economically extracted from the face but also waste, which is usually discarded several steps further downstream in the process. As a result, a large amount of rock is transported to the surface, influencing the costs at which the ore is produced. Reducing the amount of waste rock being transported to the surface by introducing a near-to-face sorting plant would improve the in many cases strained transport system in the deep mine. In this study, one of Boliden’s cut-and-fill mines was analysed with respect to the challenges related to rock transportation and increasing mining depth. The study aims to evaluate the potential use of a new near-to-face sorting system in the operating underground mine. Discrete event simulation was used to study and analyse the rock transportation system with and without the near-to-face sorting plant. The paper shows how the underground rock transportation system and the production were influenced when the near-to-face sorting equipment was added into the current system. INTRODUCTION The locations of waste rejection in the mining processes and the cost of removing waste from the system compared with the cost and energy necessary for further comminution are important parts in the material handling system (Bowman and Bearman, 2014). In an underground mine, longer material transportation distances generate the need for further investment in the mobile fleet and ancillary equipment in order to reduce the waste from the material handling as early as possible. One of the ways of reducing the waste (coarse particle size) in material handling is by use of pre-concentration. The benefits of pre-concentration are well known (Schena et al. 1990; Feasby, 1995; Peters et al. 1999; Klein et al. 2002), as well as the factors governing the feasibility of underground pre-concentration (Peters et al., 1999) and the mining integration issues (Klein et al. 2003). In the Onaping Depth orebody in Sudbury, Ontario the study of implementing the pre-concentration resulted in increased capital costs of 6% and a reduction in the operating costs of between 20-40% (Bamber et al, 2004). In this paper, the effects on the production and the transportation system of implementing underground pre-concentration by means of a near-to-face ore sorting plant in the Kristineberg mine are modeled and analyzed using the AutoMod tool. This tool is based on discrete event simulation (DES) (Banks, 2004), allowing high flexibility in customization and enabling the user to view the production of the system before ore sorting plant integration. The sorting plant selected in the simulation is built from modules. The material is fed by conveyor and goes through the comminution, classification, sorting and service processes after which the waste is redirected to backfill headings via trucks. The system mechanically ejects the particles from the feed stream on the basis of the information obtained from both the XRT sensor’s signal and 3D laser scanner based on both density and rate of refraction of light within a particular mineral. The sorting plant could pre-concentrate the metal ore up to 300 mm size. The plant requires little auxiliary infrastructure, is easily modularized for underground installation and can be easily relocated to different areas."

Jan 1, 2016

By J. E. Hoffman, Massimo Maccagni, T. J. Keefe, Marco Olper, O&apos

The research laboratory of B.U.S Engitec has identified and patented a new process for electrolytic production of lead from lead sulphide concentrates with simultaneous production of elementary sulphur. The process occurs in an aqueous solution, at atmospheric pressure, utilizing a solution of ferric fluoroborate in fluoroboric acid as the oxidizing and solubilizing medium for lead sulphide. After the filtration and separation of a residue composed of elementary sulphur and the gangue which accompanied the concentrate, the solution containing lead as fluoroborate and iron reduced to a ferrous state is sent to a diaphragm electrolytic cell where, in the cathode compartment, the lead is deposited in a compact form on the stainless steel permanent blank. The exhaust solution stripped of lead is sent to the anode compartment where the oxidation of ferrous fluoroborate into ferric fluoroboratetakes place, reproducing the oxidizing solution for new leaching. Depending on operating conditions, it is possible to selectively solubilize the lead from the other metal values present in the concentrate. The sulphur produced from the reaction may be separated from the gangue by extraction with solvent or by flotation.

Jan 1, 1993