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By M. Brnich, S. Kramer, B. McNamara, T. Hethmon, M. Pedersen-Howard, S. Rajapaske, D. Lingenfelder, B. Huber, D. Hebig

"The development of mining safety and health management as a recognized profession has been long in coming. Over the last 150 years, the mining industry has evolved from having individuals randomly involved in safety related work with no specific responsibilities or qualifications, on to the designation of individuals responsible for safety, regardless of knowledge, qualifications and experience and finally to today’s expectation that virtually every mine and mining company has designated individuals operating as safety and health professionals. Further, with the complexity, risk potential and moral expectations surrounding safety, people who address mine safety and health management are justifiably expected to function in a professional capacity including:1. Rendering a specialized service based on advanced knowledge and skill.2. Maintaining a high degree of obligation to those most affected by mine safety outcomes.3. Bound by an ethical code in working with the public, employers and miners.4. Maintaining confidentiality with an employer or client. This historical change parallels thedevelopment of other professions, e.g., attorneys, engineers, physicians, etc., with the exception that those professions require a license granted by a governmental agency, which is justified on the basis of public protection, in order to practice. Likewise, decisions made by today’s mine safety and health professionals, both directly and in association with other managers, clearly have a significant impact on the life and welfare of miners throughout the world.CertificationIn light of this, there is growing need to improve standards of competency and professionalism for those who work in mine safety and health management. An effective mechanism to accomplish this, other than licensure, is the use of accredited professional certification programs. There are many professional certification programs for safety and health throughout the world (Hale & Harvey, 2012). However, there is only one certification specific to mining —the Certified Mine Safety Professional (CMSP). The International Academy of Mine Safety and Health (ISMSH-SME) was formed with the purpose of developing and managing mining safety and health certification programs for the Society for Mining, Metallurgy and Exploration (SME). In 2016, following the discontinuation of the International Society of Mine Safety Professionals (ISMSP), which developed the Certified Mine Safety Professional (CMSP) credential in the 1990s, the IAMSH-SME began the process of updating and relaunching the CMSP program. Among other work required to gain third-party accreditation both domestically and internationally, the IAMSH-SME has developed a new Body of Knowledge associated with mine safety and health management (Table 1)."

Jan 6, 2018

By Tom Szaraz, Steve Skelhorn

Part of a major sewer expansion for the City of Columbus, Ohio. The Big Walnut Outfall Augmentation Sewer (BWOAS) consists of 4,000m (13,200 ft) of 3.66m (12 ft)diameter tunnel passing mainly through glacial deposits with a water head of up to 2 bar. The project involves many new innovations, including: Slurry wall work shaft with excavation below the water table; Hybrid universal rings combining traditional steel reinforcement with fibers; New, full EPB Lovat TBM; Two component grout system pumped to the TBM from the surface; and, Linabond corrosion protection liner. The paper looks at the planning approach adopted to meet the various challenges presented, combined with an overview of progress to date.

Jan 1, 2007

By Jon Pocock, Ashma Singh

The traditional approach for the beneficiation of South African siliceous sedimentary phosphate ores has been reverse cationic flotation. The robustness of this approach, however, has been a concern due to its sensitivity to parameters such as slimes content, headgrade ( P2O5 and SiO2 content), reagent dosages and conditioning times. The phosphate mineralisation for the ore body under investigation is predominantly carbonate fluorapatite composed of mainly quartz and apatite and minor amounts of chlorite, ilmenite and carbonates. Beneficiation of low grade sedimentary ores containing calcareous impurities, such as calcite and/or dolomite in addition to siliceous gangue, is required to meet the increasing demand; therefore, much research has been carried out to find an alternative technique to beneficiate this material. This paper investigates traditional flotation approaches versus the currently adopted ‘Crago Process’. Comparative results are presented in terms of upgrade potential for the production of concentrate rock for downstream applications. The novelty of the ‘Crago Process’ lies in its double stage approach, i.e. direct fatty acid flotation followed by reverse cationic amine flotation. The Crago process was able to achieve higher upgrades reporting at 32.1% P2O5 compared to conventional cationic flotation only achieving grades of 18.5% P2O5. Furthermore, the recovery gain was 3%.

May 13, 2023

By Aldin Ardian, Mustafa Kumral, Jagjit Singh

Risk assessment of mining projects is a requirement in the mineral industries. In this process, many risk variables are timedependent, and the only available data are historical time series. Moreover, in the case of a multivariate scenario, conventional forecasting methods fail to capture conditional dependency across the variables, which is important when there is an underlying causal relationship that needs to be modeled for accurate project evaluation. Thus, we investigated the use of copulas to capture the conditional distribution of the factors involved in a mine risk assessment study. We employed a multivariate copula-based time-series approach to model several uncertain variables. The Autoregressive Fractionally Integrated Moving Average - Generalized Autoregressive Conditional Heteroscedasticity (ARFIMA-GARCH) model was used for the conditional mean and copulas were used to model the error distribution, thus capturing the collective variation and dependence pattern across the variables. The method was implemented to model gold prices, copper prices, and the 10-year US Treasury bond yields and to determine the project’s net present value and probability of being economically feasible. The proposed approach can be used for cases where simulation of multivariate time-series is conducted.

Apr 13, 2021

By Duane L. Whiting

The National Environmental Policy Act of 1969 (NAPA) provides guidance for federal agencies in making informed decisions. The Act has been used to determine the potential environmental impacts from mining and other natural resource operations, primarily in the Western USA. To accomplish the purpose of the Act, a process for developing environmental documents was established. The documents (EA/EISs) evaluate environmental impacts and are produced by federal agencies through public participation and cooperating agency review. Effective interactions and up front coordination between agencies and industry is required. An abbreviated history of environmental protection in the USA leading to NEPA, the driving regulation, objectives, provisions and limitations of the Act, and select mining related NEPA projects III the Western U.S. are discussed in this paper.

Jan 1, 1998

By D. Marino

Over the last 20 years, the manufacturing sector of our country has been called upon to comply with ever core stringent environmental standards. The primary metals sector was particularly hard hit early on, to develop the technology, acquire the equipment, and implement the programs to eliminate or reduce the by-products of metal making. To this end, through a combination of technological innovation and extensive capital expenditures, the metals industry has met, and in many cases, exceeded the minimum standards. It is to this escalating cost - liability exposure issue - that Dereco has addressed itself. As we move into the decade of the 90's, the challenge facing the metals industry concerning the environment will be even more difficult than the previous decade. To focus in on one major aspect of legislated environmental regulations, the issue we will address today is; now that the by-products of metal production have been identified, accounted for and collected, how are they to be disposed of? During the course of this presentation, actual data will be presented from our 4 1/4 year on-site experience at J & L Specialty Products

Jan 1, 1992

By T. J. Lutz, L. Yan, J. R. Srednicki, J. A. Yonkey, G. T. Homce

"Federal regulations require the installation of refuge alternatives (RAs) in underground coal mines. Of the in-use RAs, over 95% are mobile RAs with the remainder being built-in-place (BIP) RAs. Heat/humidity buildup has been one of the major concerns with mobile RAs. For BIP RAs, however, there is a lack of in-mine heat/humidity test data to determine the extent of heat and humidity buildup. To quantify heat/humidity buildup in BIP RAs, the National Institute for Occupational Safety and Health (NIOSH) performed a series of heat/humidity tests on a 60-person BIP RA with and without a borehole air supply. At various times during the year, tests were performed with cooled, heated, or unconditioned borehole air to examine how various outdoor temperatures may affect the thermal conditions inside a BIP RA. The results show that the air supplied to a BIP RA may require heating and cooling, depending on the outside air temperatures and the temperature of the mine. For example, during tests with an external ambient temperature above 70°F and a humidity that reached 90 %RH, providing 55°F dew point air was able to keep the internal apparent temperature below the mandated 95°F. Results for each test case are presented. INTRODUCTION The Mine Safety and Health Administration (MSHA) has required the installation of refuge alternatives (RAs) in underground coal mines since 2008 [1]. MSHA requires that RAs provide an environment with breathable air for entrapped miners for a 96-hour period. Heat buildup inside an occupied RA is a serious concern. Without a means to dissipate the heat and humidity generated by the occupants and the carbon dioxide scrubbing system, the temperature and humidity inside RAs could lead to severe discomfort or heat stress depending on the mine ambient temperature before and during occupation of the RA. In its 2006 report, the West Virginia Mine Safety Technology Task Force recommended an apparent temperature limit of 95°F for RAs [2]. In 30 CFR 7.504, MSHA specifies a maximum apparent temperature of 95°F inside an occupied RA [3]. The apparent temperature is calculated using both air temperature and relative humidity [4]. To determine if their RAs meet the apparent temperature limit, RA manufacturers have been performing 96-hour-long heat and humidity tests in laboratories. During these tests, a heat input of 117 W (400 BTU/hr) per person is used to represent the metabolic heat of a single miner [2]. The heat generated by the RA’s carbon dioxide system is also accounted for in testing. To account for this heat, 50 W (170 BTU/hr) of heat per miner is used for a lithium hydroxide scrubbing system, or 30 W (100 BTU/hr) of heat per miner is used for a soda lime scrubbing system [5]. In these tests, air velocities around the RA are minimized to represent the worst-case scenario of an interruption in mine ventilation that might occur in a mine disaster."

Jan 1, 2017

By J. Kretschmann

According to the model of product life cycles, the global coal mining industry is in the stagnation phase. The coal demand of the main consumer, China, has peaked in 2013 and is slowly declining. The Norwegian sovereign wealth fund, the world´s largest, has excluded coal-related companies for ethical reasons. Important players like the UN or the EU have already begun to describe pathways towards de-carbonization. Increasing competition between coal mining companies and the mining regions can be expected worldwide if companies want to keep their positions on the global and national coal markets. Companies will focus on the best deposits. European countries like France, Spain or Germany are only forerunners of this development - their centuries of coal production have been finished. The concept of Sustainable Development (SD) is fundamentally based on a model of progress where ecological, economic and social dimensions should be developed equally and positively. But without the idea of competition, the concept of SD is incomplete. Questions arise, such as: How can SD be realized on stagnating or declining markets without guarantees for companies “to live forever”? How can SD be a corporate goal in a phase of decline? How can declining mining regions sustainably progress into a better future? The German hard coal mining industry´s lifecycle has ended in 2018 after 60 years of stagnation and decline. As of 2019, all hard coal consumed in Germany will be imported, especially from Colombia, Russia and South Africa. What has been done in Germany to handle the coal decline in a sustainable way and the lessons learned from this process is described in this paper. It may be useful for mining regions who will face a similar future sooner or later. INTRODUCTION Principally, mining natural resources is a finite business that reaches its limits once the deposits mined are depleted, the resources can no longer be mined in an economically profitable way, or substitutes are pushing the mined products out of the market. An example for the latter is the increasing replacement of coal with natural gas and renewables in power generation in the USA. (Kok 2017) According to the model of the product lifecycle, the global mining hard coal mining industry has reached the stagnation phase. (Kretschmann 2000) Although the coal mining business is more a multi-regional than a global business the trend is obvious. The peak of coal use is behind us, especially because the coal demand of China is slowly decreasing since 2013. (Shell 2018) China´s government has announced investing $360 billion in renewable energy by 2020 and scrap plans to build 85 coal-fired power plants. In March 2018, Chinese authorities reported that the country was already exceeding official targets for energy efficiency, carbon intensity, and the share of clean energy sources. China’s energy regulator, the National Energy Administration, rolled out new measures to reduce the country’s dependence on coal. (Kejun and Woetzel 2017) Coal consumption in the US is facing a 16 % decline in five years from 800 to 670 million short tons between 2015 and 2019 and - according to the EIA – will not rise again. (EIA 2018) The decline is attributed to complex market dynamics from low gas prices because of the “shale gas revolution” (Kok 2017, p. 3) to federal environmental regulation like the Clean Power Plan. The United Nations´ UNEP Finance Initiative is cooperating with the Portfolio Decarbonization Coalition of institutional investors to implement decarbonization strategies across their portfolio. Amongst these investors is the New York State Common Retirement Fund, the third largest public pension plan in the USA. (UNEP 2017) The European Union has already begun to de-scribe pathways to decarbonization. (European Union 2018) The Norwegian sovereign wealth fund, the world´s largest, excluded coal-related companies for ethical reasons. The oil giants Total S.A. and Royal Dutch Shell, tradi

Jan 1, 2019

Several economic factors have caused the surface mining industry to require large-capacity shovels and trucks for efficient, high-production, low-cost operations. Some of those factors include technological advancements in equipment, commodity market depressions, increased labor and maintenance costs, contractural obligations and harsh operating conditions. The difficult operating conditions in surface mines, however, pose challenges to the use of high-capacity equipment. They include space limitations, weak over-burden, and weathered soils and rocks. So mining companies face major challenges in selecting appropriate shovels to meet the technical, operating, safety, environmental and economic requirements of their mines.

Jan 1, 2003

By Evgueni Jak

Pyrometallurgy is an important sector of modern industrial society actively participating in solving current environmental, economic, materials scarcity and other challenges. Recent advances in analytical methods, experimental techniques, thermodynamic, phase equilibria and process modelling tools provide new opportunities to increase the productivity of pyrometallurgical reactors, the treatment of complex feeds and metal recoveries. Fundamental theoretical models can now be used to make a significant next step towards the development and implementation of computerised models describing real industrial processes—Virtual Reactors, and computer-aided smart-decision-making systems that may be called Pyro-GPS by analogy to GPS; these developments can facilitate knowledge-based improvement and optimization strategies. The implementation of these improvements require ongoing collaboration between researchers, industry and government

By Piyush Rai, Suresh Kumar Sharma, Punit Paurush

The present study has been conducted in surface limestone mine to select the controllable blasting design parameters affecting the peak particle velocity (PPV) for assessment of ground vibration. The study aims at using two prominent statistical tools, namely, principal component analysis (PCA) and stepwise selection and elimination (SSE) techniques for identifying the key controllable parameters affecting the PPV. For determining the correlation coefficient between blasting design parameters and PPV from 44 field scale trial blasts, multi-variate linear regression (MLR) technique was done. It was found that the PCA and SSE eliminated a huge number of controllable parameters to identify the most important parameters, affecting the PPV. The PCA eliminated 6 number of parameters while SSE eliminated 5 number of parameters, and the coefficients of determination (R2) obtained were 0.616 and 0.584 for PCA and SSE respectively. The predictor equations were evolved, and these equations were used to validate the PPV results for another set of 21 field scale trial blasts. The predictor equations have been found to be fairly accurate in predicting the PPV values. Further, the PCA technique provides very near prediction of PPV with high degree of correlation in comparison to SSE technique. The paper highlights the role of state-of-art statistical tools in selecting the blasting design parameters affecting the PPV in field-scale blasting.

Mar 1, 2021

By T. R. Jr. McMillan

Introduction Examining the short- and long-term job prospects for engineers in the coal industry might include looking at coal tonnage projections, future export markets, federal regulations, and the decrease in overall graduates. But coal is the US most competitive basic industry. As such, why not go back to basics? That is, there are three basic challenges that need to be faced by students, faculty, and members of the coal industry. These challenges are counseling, career placement, and professionalism. Counseling Counseling can include elementary, high school, and college students, as well as individuals already employed. But what happens to students after they have selected a course of study at a particular university? As shown in Fig. 1, only 87,000, or 7.25% of our graduates have technical degrees. Generally, there is a strong market projected for these engineering graduates. However, many students who have majored in other nontechnical curriculums, have to scramble for jobs. This says something about our ability to make students aware of where the real job opportunities are. As a student spends four or five years pursuing a degree, he or she is looking for professional guidance. The student has the right to expect "real world" counseling - counseling that is not "the way it should be" but "the way it is." The influence of faculty members is significant. They should take this long opportunity to tell students not what they want to hear or what the problem's of academia or the industry are, but what the real job market is all about. If faculty do not use this opportunity, they in-advertently-through omission - mislead their students. Once a student graduates and is a working alumnus, faculty should take advantage of their relationship with the student and continue to stimulate conversation leading to a two-way exchange of ideas and information. Faculty should also encourage and solicit financial support for their mining departments from their alumni. These monies, in many cases, will be matched dollar for dollar or more, depending on the company the alumnus works for. In the private sector, the responsibility is to communicate with faculty and students. Alumni can be effective by participating in this two-way dialogue with their professors at meetings, technical seminars, and conventions. In many cases, alumni will employ summer or co-op students in their organizations. While getting to know these students, industry members should level with them on where the true opportunities are and what it takes to be successful. It is important to communicate with both faculty and students candidly on both the posi-

Jan 2, 1985

By D. Richter

The Pyrometallurgical refining stage of ferronickel manufacturing produces a slag rich in iron and nickel, which is usually further processed for metal recovery. The recovered material is returned to the refining or smelting stages, depending on the amount of impurities. A series of tests was carried out on the Mineração Morro Azul refining slags, aiming at the recovery of the metallic particles through physical processing. Minor changes in the process showed improved results. This paper compares the textures of these slags after being cooled at ambient temperature and granulated under water at high pressure and flow. It concludes that the cooling process is intimately connected to the work index of such slags, thus resulting in direct impact in operating costs.

Jan 1, 2011

By F. N. Siddiquie, Mohd Shaif, Rajiullah Khan, Juned Alam

Manganese ore bodies of Banswara Mn belt were classified into stratiform and stratabound types, based on their mode of occurrence, distribution, and their chemical characters. These ore bodies generally composed of braunite, pyrolusite, cryptomelane/ psilomelane, wad, etc. The stratiform-type Mn ore bodies are conformable with the associated host rocks (Mn phyllite, etc.) and occurred in the form of layers, bands, etc., which are variable in their shape and size. These ore bodies are also strongly folded with the enclosing host rocks. The others, which are stratabound-type Mn ore bodies, also showed an intimate association with the associated host rocks. These types of ore bodies occurred in thin layers, pockets, lenses, stringers, etc. The classified ore bodies are confined with Kalinjara formation of Aravalli Supergroup of Paleoproterozoic age. The ore bodies are structurally controlled and well associated with phyllite, schist, limestone, quartzite, etc. The stratiform-type ore bodies constitute a marginal to low Mn grade and are also characterized by lower Mn content (26.19–39.24%) along with the Mn/Fe ratio of 7.16–12.23, while the stratabound-type Mn ore bodies are rich in Mn (35.92–49.64%) along with the higher Mn/Fe ratio of 14.15–23.97. However, the poor Mn grade along with high siliceous impurities of Banswara Mn deposits is subjected to them for intermittent mining activities in the past and, consequently, did not attract the scientific and industrial community for the evaluation of these resources. Therefore, the authors attempted this study in a scientific and systematic manner (mode of occurrence/distribution and possible methods for evaluation/exploration) to evaluate the potential of existed and newer Mn deposit resources in the Banswara Mn belt. The whole findings would be very much helpful for exploration/ mining geologist along with other concerned, to completely evaluate these Mn deposits in the future.

Aug 16, 2021

By David C. Girard, Larry Williamson, Leonard R. Benson, Ronald E. Bizzarri

On the east side of Washington DC, the DC Water & Sewer Authority is developing a Facility Plan for the Anacostia River CSO Control Projects, including 8 to 12 miles of CSO storage/conveyance and flood relief tunnels and associated facilities. The project includes major technical and non-technical challenges, including: completion under a Federal Consent Decree schedule; large diameter (estimated 25 to 35 ft) soft ground tunnels and shafts up to 200 ft depth; operations without use of active flow control systems; and close coordination with several major public and private construction and development projects that are being advanced in the project area.

Jan 1, 2007

By N. Dhawan

With ever-increasing demand, low-grade complex ores and strict environmental regulations, metallurgical processing options have become limited. Heap leach technology provides several benefits to combat these issues including low cost, flexibility and diversified process conditions. This paper provides an overview of heap leaching technology with specific emphasis on chemical aspects. Hence, influencing factors, advantages and disadvantages, testing approaches and some fundamentals will be discussed. Finally, heap leach technology for different ore types (copper, nickel, uranium and gold) will be briefly compared.

Jan 1, 2012

By John W. Sweeney

Florida is usually thought of as a vacation State, not a mining State, yet Florida has been the leading producer of phosphate rock in the United States for 85 consecutive years and in 1978 supplied over 80 percent of the national output and over 30 percent of the world's output. It is estimated that the Central and South Florida phosphates contain 412,800 short tons (374,000 metric tons) of U308, that 115,000 short tons (104,000 metric tons) of U308 will be contained in the wet-process phosphoric" acid procsssed in the United States through the year 2000, and that 54,000 short tons (49,000 metric tons) of U308 will be available from Florida. In 1978, two companies in Florida and one in Louisiana went on-stream recovering uranium oxide from wet-process phosphoric acid and three others started construction of U308 extraction facilities. These six companies will have the capacity to recover 2,137 short tons (1,900 metric tons) of U308 annually in 1980, which will account for about 15 percent of our domestic requirements.

Jan 1, 1979

By Sufi Md Gulzar, L B. Roy

Rock engineering tasks like tunnelling, dam and building construction, and rock slope stability rely heavily on properly estimating the rock’s uniaxial compressive strength (UCS), a crucial rock geomechanical characteristic. As high-quality specimen are not always possible, scientists often estimate UCS indirectly. The primary objective of this paper is to assess the efficacy of long short-term memory (LSTM), K-nearest neighbour (KNN), a combination of particle swarm optimisation (PSO) with an artificial neural network (ANN), and adaptive neuro-fuzzy inference system (ANFIS) to estimate the UCS of sandstones from Jharia, Dhanbad, India. Point load index (PLI), porosity (n), P-wave velocity (Vp), density (ρ), and moisture content (%) are the parameters used for the present study. Finally, a comparison was made between the various prediction algorithms outputs. The findings of the study validated the effectiveness of computational intelligence methods in forecasting UCS compared to other models used in this paper. The KNN achieves overall the best results, with an R2 of 0.95 for training, 0.94 for testing, and an RMSE of 0.03 for training and 0.05 for testing.

Nov 23, 2023

By E. Jackson

This paper describes highlights of the Placer Dome MiniMole project - the development and testing of a robotic machine for mining narrow ore veins. A prototype hydraulically controlled robotic machine was built and tested. The machine provided a platform for testing numerous cutters in the field. Other cutters, e.g. undercutting devices, were tested in the lab. Extensive analyses were done on specific energies and cutter penetration. Three sets of quarry trials were done, then the machine was tested in an underground mine. Rock UCS values varied from 180 MPa to 230 MPa. The paper includes lessons learned and recommendations based on the project findings.

Jan 1, 2007

By H. Sevim

Mining engineering curriculum has been discussed and debated in meetings and conferences, and opinions and recommendations have been published in the literature since the inception of the official degree-granting mining engineering program at the Columbia School of Mines in 1864. The deliberations have usually been heightened during the periods of boom-and-bust cycles experienced by the mining industry since the 1920s. Currently, the global natural resource industry is undergoing another cycle, called ?super cycle,? characterized by elevated prices for metals and other natural resources. The super cycle is occurring as a result of the large deficit between the global supply and demand for natural resources, due, in large part, to economic expansion and development in countries such as China, India and Brazil. Because of this cycle, there is a shortage of mining engineers in the U.S., Canada and Australia.

Jan 1, 2012