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By Jim Wilcox

Introduction In 1979, rumors of a developing drug problem within IMC Fertilizer's Carlsbad, NM workforce began to surface. For the next two years, a management team contacted local, state, and federal regulatory agencies that had the potential resources to help combat this apparently escalating problem. These contacts included the local police department, the county sheriff's office, the federal Drug Enforcement Administration, and the Mine Safety and Health Administration (MSHA). IMC approached each agency with two proposals. The first required the agency provide an undercover agent for placement in the company's underground facilities. The alternative required the company to provide the agent with the participating agency lending necessary legal expertise and guidance to accumulate the necessary data. MSHA regulations prohibit intoxicating beverages and narcotics on mining property. They also forbid persons under the influence of alcohol or narcotics from working in or around mines. The agency could not, however, help with this problem. The remaining agencies were sympathetic, but were unwilling to assist in implementing either program, citing legal implications. Without exception, these agencies not only refused to provide help, they discouraged any type of undercover operation, searches, drug screenings, or using dogs trained in narcotics detection. As law enforcement officials, they reasoned that any such program constitutes potential civil rights violations. An attorney advised IMC that it was not required to adhere to the same guidelines as law enforcement and regulatory agencies. It was his legal opinion that the company could conduct an undercover operation. But he recommended finding a private firm that specialized in this type of investigation. An experienced firm should have the expertise to conduct the operation and avoid the legal pitfalls that could be encountered. The management team agreed with the attorney and elected to hire a private firm. After extensive research and evaluation, three reputable companies were contacted, advised of the needs, and asked to submit a proposal. Their initial response was enthusiastic. None, however, submitted a proposal. Each was unable to locate a qualified agent willing to work in an underground environment. Privacy and civil rights At this point, it was apparent that an undercover operation was not feasible due to the lack of inhouse expertise and the lack of outside assistance. After more research, it was concluded that the only viable options left were the ones that the law enforcement community had earlier discouraged. These options included locker and personal searches, use of dogs trained in narcotics detection, and drug screening or testing. The management team evaluated the pros and cons of locker and personal searches. They concluded that if conducted properly, this approach could eliminate the problems. The potential legal liabilities, however, appeared to be tremendous. Strict guidelines would have to be adhered to in order to avoid invasion of privacy and civil rights violations. This meant announcing locker searches before conducting them and obtaining written permission from an individual before searching his person. Although the group was reluctant to lose yet another option, it was concluded that conducting searches under these conditions would be ineffective. It would also convey the message to the workforce that the substance abusers had the upper hand. This author was extremely critical of this legal opinion at the time. I have since concluded that the attorney was correct. This occurred in mid-1982. Court decisions of that era indicated the legal and political climate was sensitive to these issues. These activities would probably have been prohibited even if they were

Jan 11, 1987

By Charles A. Beasley

Increased technical and legislative analysis by all parties of interest could result in more efficientand better directed regulatory legislation in the mining industry. Efforts to forestall or frustrate legislation through massive lobbying and public relations efforts are seldom effective over time and often lead to more stringent and far reaching legislation than necessary. The Federal Coal Mine Health and Safety Act of 1969 is perhaps an outstanding example of such insufficiences; a future example may well be regulatory surface mine legislation. Although a lack of extensive hard data seldom enables rapid or sophisticated analysis early in the legislative process, even preliminary analysis may be sufficient. Simple statistical analyses of available data, assessment of the legislative rationale, and subjective appraisal of other non-quantifiable constraints to improved mine safety. An average of 115 underground fatalities at an exposure frequency rate of 0.67 can be reasonably expected in the immediate future, under existing levels of technology, degree of regulation, and economic conditions. If gross unrefined estimates of 6 preparation plant, 5 surface, and 30 strip mining fatalities are assumed, the total fatality industry level could be expected to approximate 156 Serious professional, economic, and technical constraints within the the industry probably preclude any major decrease of these accident levels within the near future

Jan 1, 1972

By S. Cotten

The concept for a Mine Escape Vehicle (MEV) is motivated by the desire to enable personnel to evacuate a mine rapidly as the first and most desirable response to any underground emergency. Under a NIOSH contract, Raytheon UTD developed a conceptual design for a vehicle that coal miners could use to facilitate their rapid exit from an underground coal mine in the case of emergency, including fire or explosion. The vehicle requirements include the capacity to provide life support functions for a number of miners, operate in an oxygen deficient, low or no visibility atmosphere, and travel at speeds faster than miners can walk out of the mine. To develop the MEV concept, three primary tasks were identified and executed. The first task focused on developing a realistic concept of operations (CONOPS) and associated high level vehicle requirements. The second task identified and evaluated currently available equipment and technologies that could be applied to address the CONOPS. The final task developed a design concept that integrated the identified components for the five (5) MEV sub-systems to provide the foundation for future detailed engineering design and prototype construction. The resulting MEV design concept is centered upon retrofitting existing mine personnel carrier chasses with available, mine-worthy equipment capable of addressing the MEV requirements. This approach offers a practical and economic avenue to prototype development and delivery with minimum lead-time and risk. Furthermore, by integrating familiar and available equipment into the design and CONOPS, the resulting Mine Escape Vehicles should also be more readily accepted by the mining industry.

Jan 1, 2010

By R. L. Schmidt, Williamson. T. N.

INTRODUCTION This paper describes one of several research projects funded by the Advanced Research Projects Agency to extend the technology of rapid underground excavation. This study and field research effort are to investigate alternative means to determine rock and geological conditions in advance of a tunnel boring machine (TBM). Approximately 1 year of a planned 3-year program has resulted in the definition of three candidate drill systems. Hardware has been assembled to field test these candidates and testing has begun. The 3-year objective is to develop a single optimum prototype drill and test it in an active TBM operation. ACKNOWLEDGMENT This research was supported by the Advanced Research Projects Agency (ARPA) of the Department of Defense and was monitored by the Bureau of Mines under Contract No. H0210037. The authors and sponsoring agencies are indebted to the quarry operators in California, Virginia, and West Virginia who offered assistance including access to their properties.

Jan 1, 1997

By Christian Heinz, Doug Harding

TBMs can last for decades and be rebuilt project after project with proper maintenance. How successful can rebuilt TBMs be? At the DigIndy Tunnel System in Indianapolis, Indiana, USA, a rebuilt TBM was used to great effect. The 6.2 m diameter Main Beam, originally manufactured in 1980, bored 40+ km of tunnels and set three world records in its size class of 6 to 7 m, including a best month of 1,754 m. In this paper, the authors analyze the TBM rebuild, performance and lessons learned to make recommendations for future projects seeking to use rebuilt TBMs over long distances.

Jun 23, 2024

By Daniel E. Collins

Massive banded Fe-Zn-Cu-Pb sulfide deposits in the Bagdad are associated with metamorphosed eugeosynclinal mafic volcanic and intrusives rocks Precambrian age. The geologic environment is very similar to that of the Jerome-Prescott area which lies 70 km. east of Bagdad. Mining of massive sulfides deposits began in 1917 on the Copper King mine in spite of its early discovery and the discovery of the Old Dick mine in 1882. The first shipments of zinc ore from the Copper King were hand sorted and averaged 46.89% Zn, 5.7 oz. Ag, 3.58% Pb and 1.68% Cu. Oxidized copper was first produced from the Old Dick mine in 1943~ In all, five deposits of massive sulfide ores have been mined in the Bagdad for a total production of nearly 2 million tons with an average grade of 12.0% Zn and 3.6% Cu. The largest deposit, the Bruce mine is currently closed because reduced metal prices and has produced a total of 823,000 tons of Zn-Cu ore to date. Mining of massive sulfide ore in the Bagdad area is presently idle. However, the potential for locating yet undiscovered ore bodies is good. Exploration for new ore bodies is difficult at best due to the complex geologic history of the area, the small size of individual ore bodies and lack of understanding as to the formation of massive sulfide deposits. The purpose of this investigation was to obtain a better understanding of the host rock formations through detailed geologic mapping, petrography and chemical analysis.

Jan 1, 1977

By H. C. Liang

Reverse osmosis (RO) and nanofiltration (NF) are widely regarded as being best available technologies (BATs) for removing contaminants of concern from water. In recent years, NF or RO treatment has increasingly gained more acceptance in the mining industry for treating mine water to remove a wide assortment of contaminants, either for meeting discharge standards or for internal re-use in mining processes. Consequently, the number of NF or RO membrane mine water treatment facilities has steadily increased. Although NF or RO membrane filtration can be a powerful tool in mine water treatment, especially when multiple contaminant removal is required, it also has many potential disadvantages. Besides the generally higher capital and operational costs for the high pressure membrane processes, organic constituents in mine water may foul the membranes, while inorganic compounds such as gypsum, calcite, or silica are liable to scale the expensive membranes if proper pre-treatment processes are not implemented. Additionally, because these membrane treatment processes generate a substantial reject or brine waste stream in addition to the clean treated water or permeate stream, brine management also needs to be considered carefully when deciding upon the viability of an NF or RO mine water treatment process. Because of these issues, it is important to conduct detailed analyses of the trade-off between selecting NF or RO vs. using chemical treatment processes when designing a mine water treatment facility.

Jan 1, 2012

By W. N. Hamilton

British Columbia is geologically favourable for a rich variety of industrial mineral occurrences. Some have been produced for years, others overlooked until recently. Major production occurs for asbestos, gypsum, limestone, magnesite, silica and sulfur; lesser production for a dozen others. For several of the minerals, potential is much greater than existing production. New production opportunities exist also for diamonds, niobium and REE minerals, fluorspar, kyanite, nepheline syenite, talc, and several others. Alberta, though geologically less diverse, also has many industrial minerals. Limestone, salt and sulfur have the major production; clay and shale, silica, sodium sulfate and a few others lesser production. Opportunities exist for expanded production, and for new production in heavy (Ti -Zr) minerals, formation brines (Ca-Mg-I-Li), and gypsum.

Jan 1, 1987

By Andrew Scogings

The current edition of The Australasian Joint Ore Reserves Committee (JORC) Code was published in 2012 and, after a transition period, the 2012 edition came into mandatory operation on Dec. 1, 2013. There is a significant change between JORC 2004 (Clause 44) and JORC 2012 (Clause 49) for the reporting of industrial mineral resources and reserves, which should be addressed by ASX-listed players in the industrial minerals space.

By T. Veneroso

Comminution is the process by which rock or ore is reduced to a size where the liberation of the minerals is maximized without changing the chemical or physical properties of the rock. Comminution accounts for about 50% of all energy that mines use (Klein et al., 2018). Growing demands from stakeholders and shareholders for sustainable development and CO2 reduction will increase the need for energy-efficient comminution. Ores with different mineralogical characteristics, textures, strengths, apparent stiffness, and mass-specific fracture energies need to be processed with a specific, new, and efficient comminution technology to increase the production and profitability of mining companies. The adoption of crusher wear parts built with new materials, such as non-Hadfield manganese steel or synthetic materials or traditional manganese with wear-resistant components, could improve the efficiency of the crushers, reduce downtime, increase production, improve the desired P80 (the aperture through which 80% of the product will pass) product size distribution, and enhance mine safety.

Feb 1, 2023

By A. Mei, F. Amadini, F. Cernera, D. Baliani, A. Flor, M. La Morgia, F. Sassi

The risk of TBM jamming because of squeezing rock mass or excessive caving (instability of the cavity) conditions is always a focal point while boring long and deep tunnels with shielded TBMs. Mechanized excavation provides a large amount of real-time data, for each machine’s parameters. Several analyses have been executed to assess the correlations between different sets of TBM parameters for the exploratory tunnel. Instead of analyzing the full dataset, a different approach is proposed, with data processed sequentially to simulate the real excavation situation. The probability distributions are recalculated together with their statistical parameters while advancing. This approach is extended also to the training of a Machine Learning model able to foresee the behavior at future rings based on past rings (using a Recurrent Neural Network). The predictions show a promising first step toward creating practical tools that can assist contractors and designers to correlate and predict TBM excavation data. These tools will assist to predict and quantify high risk situations that could arise during excavation.

Jun 13, 2023

By C. Sun

With complex component, higher salt content, low biodegradability, DSD acid oxidation wastewater could not be efficiently dealt with traditional methods. It is pointed that the coal water slurry could be made with DSD acid oxidation wastewater of different concentration and the density of coal water slurry could be up to 70%, while its viscosity is only 850~930 mPa?s. The coal water slurry could be perfectly jetted and burnt under different conditions. The higher density the DSD acid oxidation wastewater has, the better properties the coal water slurry have. The pollution components and characteristic group of DSD acid oxidation wastewater are similar to the additives of coal water slurry, so it could be used as a kind of usable additive of water coal slurry. It is so reasonable and feasible to make coal water slurry with DSD acid oxidation wastewater that the pollution of DSD acid oxidation wastewater can be solved completely.

Feb 23, 2014

By X. Zhu, L. Chen, R. Guru, M. Peiravi, M. Mohanty, L. Ackah, B. Xu

"The overall goal of this study was to develop a suitable flowsheet to extract rare earth elements (REEs) from coal ash. Only the findings from the first part of this study is being reported at this time. A total of fourteen coal samples of different ranks were examined for REEs concentration. An anthracite coal sample, originating from Pennsylvania having more than 700 ppm (in the coal ash) was selected for the REE extraction tests. The experimental program completed so far included high temperature leaching using nitric acid, followed by the solvent extraction tests. A 4x2x2 experimental design was used to conduct a total of thirty two high temperature leaching tests by varying acid molarity (at 4 levels), solid content (at 2 level) and leaching time (at 2 level). The highest LREE (light REE) recovery of 90% and HREE (heavy REE) recovery of 94% were obtained from the most optimum leaching test condition while maintaining the impurity recovery to the leachate at less than 40%. Solvent extraction experiments were conducted to recover the REE’s from the above leachate solution using a variety of organic extractants including, TBP, Cyanex, D2EHPA and their combinations. D2EHPA was found to be the best extractant during this SX text series providing nearly 99% recovery of REEs. INTRODUCTION The demand for rare earth element and other strategic metals (REM) in the world is rapidly increasing due to their use in a variety of high technology applications. More than 100,000 tons of rare earth oxides (REO) are being used worldwide on an annual basis. However, we have less than 10% of the world reserve of rare earth element (REE) mineral deposits in the US. More than 60% of rare earth oxide (REO) was imported to the US from outside (mostly from China) in the year of 2013. However, China’s institution of export quota has significantly reduced the supply of REMs to the U.S. Hence, new ways of producing REM and/or finding substitutes for those metals for the high-tech applications need to be invented/discovered in a timely manner. Coal Combustion Byproducts (CCBs), which are discarded as waste materials in most cases, are known to contain REEs (in low concentration) that could be extracted using a suitable process flowsheet. This may be a worthwhile route to pursue considering the short supply of REMs and the abundance of coal ash in thousands of ash ponds in the US. On an annual basis, more than 110 million tons of Coal Combustion Byproducts (CCBs) are being produced while satisfying our nation’s need for electricity (ACAA, 2014). However, less than 50% of these CCBs are being successfully used in various applications and the remainder is being dumped as waste materials in the landfills and ash ponds."

Jan 1, 2017

By J. C. Reid

Pre-cambrian scheelite deposits in Northeastern Brazil are widespread in a high grade metamorphic terrain. Previously these deposits had been interpreted as contact-metasomatic. In this paper, a volcanigenic model is invoked based on the volcanic setting (proximal to distal) and the absence of associated felsic intrusives and spatially associated metasomatic skarns. The tungsten was introduced into sediments by volcanic- exhalative processes and subsequently remobilized and further concentrated by heat and metamorphis fluids associated with high-grade metamorphism and migmitization. An alternative syngenetic - diagenetic model is discussed which requires the transport of tungsten by heteropoly acids and deposition of the tungsten as a function of Eh and Ph conditions and different clastic depositional environments. While such stratabound tungsten deposits are considered rare in North America, the hypotheses developed in this paper may open new areas for exploration.

Jan 1, 1983

By Greg Watson, Dennis Ofiara

"TBMs have been used in mining in decades past, but their use has been limited and sporadic, due to both perceived and actual application difficulties. With new technology and mounting success stories, this is changing. For both coal and metals mining, deep ore bodies require long access tunnels, and an efficient and economical method of reaching those deposits. Today, mining engineers are considering TBMs as part of the overall mine development plan. Planned TBM mine drifts are not only longer, but have more complicated trajectories. Mine development TBMs will have to cope with varying geology, potential for high water inflows, steep gradients, and high temperatures. TBM systems are being planned to cope with such difficulties. TBM systems will be considered and increasingly deployed for mine development, even if commodity prices remain low. TBMs can satisfy the need for increased productivity, better life of mine infrastructure, and safety. Effective conveyor systems are essential to support TBM operation in many mining applications. Many mine development tunnels are slopes, driven down at the steepest practical gradient to reach the deep ore body. Conveyors are often the only safe and effective way to haul the TBM muck form such tunnels. This paper will review the historical use of TBMs in mining, and will discuss the 2015 status of TBMs and conveyor systems in mining, and the special requirements and adaptable features needed in order to make efficient TBMs a reality in mines worldwide.HISTORICAL USE OF TBMS IN MINING APPLICATIONS The first successful hard rock TBM was invented in 1954. Over the next decades, TBMs have been used in many mining applications: Mine access drifts in several Spanish mines •,White Pine Copper Mine, USA •,Selby Coal mine drift, UK •,Coal slopes in Appalachia, USA •,German coal mines accdess drifts, several mines •,Magma Copper San Manuel, USA •,Cape Bretton Undersea Coal Slopes, Canada •,Stillwater Mines, USA"

Jan 1, 2016

By Brian V. Roulston

Potash is Canada's leading industrial mineral in terms of value of production, with 11.1 M tonnes of muriate of potash produced in 1992 for a value in excess of $1 billion U.S. Each tonne of potash produced generates about 2 tonnes of waste salt, together with slimes and brine. The disposal of these waste products, particularly the salt and slimes which are discharged on the surface, has recently become an environmental concern. This concern is forcing companies and regulatory authorities to review disposal practices. In New Brunswick, on Canada's east coast, Potash Company of America operates a mine at which 2 M tonnes of potash ore and 0.5 M tonnes of rock salt are mined each year. The mine is situated in an environmentally sensitive area, noted for its dairy farming and salmon angling. In such an area it was recognized that the storage of waste on surface would be unacceptable, and the mine was designed around this principle. Three main waste streams - salt, slimes, and brine - must be managed as an integral part of the mining system. Around 1.5 M tonnes of fine salt tailings from the milling process and the rock salt screening operation, are sent directly to the active cut-and-fill potash stopes to be used as backfill. Slimes and excess brine from the mill are piped underground as a slurry to be discharged into one of the basin shaped stopes created by mining of the rock salt. While the slimes settle out, the clarified brine is withdrawn from part of the stope to be pumped to surface as a feedstock for the evaporator - a process which recovers the contained potash values in the brine. By designing a system which integrates the mining, processing and disposal of all product streams, and by careful production planning, it has been shown that zero effluent potash mining is possible and points the way for the industry in the future.

Jan 1, 1995

By Enrique Levy

Central America is graduating this year into large scale mining with the start up of Inco's multi-million dollar nickel laterite processing plant in Guatemala. In the other extreme of the Isthmus in Panama Texas Gulf Sulphur is doing check diamond drilling and foundation test drilling at the Cerro Colorado copper porphyry. The higher price of gold and silver has spurred development and exploration of several small precious metal mines. The purpose of this presentation is to make a brief resumé of the most important mines operating in the area and a list of significant exploration projects. Also, tables will be shown to compare mining codes and taxes. Unfortunately these tables lack information on Panama. Before starting I like to express my appreciation to Kennecott Copper who permitted the use of some of the data compiled by the author on their behalf during the year 1975. Other persons which did not want to be named also have my gratitude.

Jan 1, 1977

By T. V. Ramey

Heap leaching in certain parts of the world, such as Chile's Atacama Desert, brings unique design problems in the form of possible large differential settlements of the foundation soils due to the dissolution of salts in northern Chile the soils often contain very high concentrations of soluble salts (nitrates, potassium, magnesium, and common sodium). When a leak in the liner occurs, the escaping solution dissolves these salts and triggers differential settlement. If the settlement is great enough, the geo-membrane tears, the leakage increases, triggering more differential settlement. The nitrate plants have experienced many occurrences of this phenomenon where a brine pond will undergo a sudden and complete loss of the impounded liquors. The authors present a simplified technique to quantify the differential settlement resulting from dissolution and provide a method which can be used to select a geo-membrane with suitable flexibility under axi-symmetric (multi-axial) load conditions to tolerate the predicted settlement. (This paper was previously published for Randol Gold Forum 1996 [Ref. 6]).

Jan 1, 1997

By Nikhil Dhawan, Veeranjaneyulu Rayapudi, Singh Rahulkumar Sunil

The ever-increasing demand for steel and the subsequent depletion of high-grade ores requires the massive utilization of low-grade iron ores. In the present study, an iron ore slime sample containing 56.1% Fe was investigated using physical beneficiation, carbothermal reduction, and a microwave-assisted process; however, physical beneficiation and microwave exposure were found to be inefficient as they yielded lower iron recovery. Using coconut shell as an alternative reductant was found to be promising and does not lead to the formation of higher iron oxides, such as fayalite and wustite phases. The microwave-assisted carbothermal reduction was found at par with conventional reduction, saving time and heating. The optimum magnetic concentrate obtained in both carbothermal reduction routes (microwave and muffle furnace: Fe grade, Fe recovery, and yield of 64.3, 97, and 84%, and 67, 99, and 83%, respectively) are suitable for alternative iron-making or blast furnace units.

By Eugene P. Pfleider

The mining industry of the World, and particularly of the United States, has made a complete reversal from underground to surface mining methods since the turn of the 20th Century. This has occurred even as average ore grades were decreasing and strip ratios rising. In the early 1900's there were over 100 underground mines producing from the three iron ranges of Minnesota -- today there are hone. Practically all of our coal prior to 1930 was mined underground; today over one-third is from surface operations and that percentage is increasing. Although world mining has hot changed to surface techniques as rapidly as has the U. S. Industry, the shift is escalating and will approach our figures shortly. A comparison of World and U. S. production figures are shown in Table 1, taken from the AIME Surface Mining volume, and the trend rates for the U. S. are depicted in Fig. 1.

Jan 1, 1968