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By P. Anyon

Exposure to the microscopic particles in diesel engine exhaust can lead to serious health problems, including the incidence of cancers, heart disease and increased susceptibility to respiratory ailments such as pneumonia, bronchitis, and asthma. In Australia, mining companies and state government authorities are actively responding to this major occupational health and safety issue. Their initiatives place considerable emphasis on routine monitoring of diesel particle matter (DPM) exhaust emissions, both for engine benchmarking and as a part of routine engine maintenance. Implementation strategies follow two complementary paths: determination of individual engines? emission signatures combined with periodic engine re-certification; and co-operatively agreed industry-government engine maintenance programs, which are subject to audit. Both strategies place heavy reliance on real-time measurement of DPM concentrations in engine exhaust, using ruggedized instrumentation, mainly based on laser light scattering photometry. Adding value to this cooperative approach, industry has also collectively funded a government agency to design and manage a database, into which the results of all-routine DPM testing can be uploaded directly by individual mines. This win-win outcome is a great example of how cooperative action between governments and industry can deliver the goods: in this case, a safer working environment, more efficient energy use and the capacity to benchmark performance with industry peers.

Jan 1, 2009

By J. M. Hird

By blending phosphogypsum with thickened mill clays, Texasgulf has successfully resolved the problems of gypsum disposal and reclamation of mined-over areas. In the process, clays are thickened to 10% solids through high rate thickeners, mixed with gypsum from a drained gypsum pile (75%) and a direct discharge from belt filters (25%), then pumped to mined-over areas. The blending of clays and the low pH gypsum yield a mixture with a pH of about 7. Dewatering is rapid to 40-45% solids within 3 months. The material spreads with very shallow slopes and within a year desiccation by high flotation ditching equipment is possible. The artificial soil is classified as a silty loam in texture, lacking only in nitrogenous nutrients. The soil material has proven to support many field crops including small grain, corn, alfalfa, and grasses. Sycamore, green ash, sweetgum and bald cypress have done well in 3 years of growth. The nitrogen source for tree growth will be made up through an alfalfa cover.

Jan 1, 1993

By T. W. Camm, J. C. Johnson

"Most engineers are bright, hard-working, reliable, and prefer to avoid conflict. An engineering curriculum tends to self-select these characteristics. By most standards, you would expect workers exhibiting these traits to require minimal supervision. But is this true? Is this how most current engineering managers lead? Looking at some current theories on leadership combined with personal anecdotes, this presentation will look at some common misconceptions about leading engineers. INTRODUCTION Engineers are different. There, I said it. From cartoons to movies to television shows and more, there is a reason stereotypes of engineers resonate. Yes, you can find a lot individual variation among specific engineers that you may know, but they do not detract from some of the overarching commonalities that engineers are known for. CLASH OF CULTURES What distinguishes a professional? Raelin (1985), in his book Clash of Cultures, describes professionals as having superior intellectual training, maintaining their own standards of excellence, and being supported by associations that maintain the quality of the profession. Engineers obviously fit all three of these ideas: an engineering degree is still regarded as one of the most difficult to attain; we maintain our own standards both through peer-review and in academia through ABET accreditation; and through professional associations like SME to promote the discipline and foster technical growth. Six characteristics representing professional status are described by Raelin (1985, p. 9): Expertise—prolonged specialized training in a body of abstract knowledge. Autonomy—the freedom to choose the means to solving a problem. Commitment—Primary interest is in pursuing the practice of one’s own chosen specialty. Identification—identifying with the profession and with fellow professionals, both through formal associations and through peers external to the organization. Ethics—providing service without concern for oneself or without becoming emotionally involved with the client. Standards—committed to help in policing the conduct of fellow professionals. Engineers are smart—in the vast majority of cases they are hired specifically for their expertise. At a typical mine the ventilation engineer knows more about mine ventilation than anyone else on site; the same is true for the rock mechanics engineer, the explosives engineer, the planning engineer who uses sophisticated computer software—each is the expert for their particular area at the mine, that is why they have that responsibility. This can present a dilemma for the manager for each (sometimes all) of these engineers. The manager needs to keep everyone on task and focused on the objectives of the organization. Because they have reached their position by following the norms and expectations of the organization, managers tend to have a certain amount of loyalty to that organization. Engineers, on the other hand, tend to have mixed loyalties, having as much loyalty and affinity for their profession as they do for the particular company they happen to be working for at any given time. This dynamic can often lead to power struggles between the managers, based on their positional authority in the organization, and the engineers, based on their specialized knowledge (Camm, 2013)."

Jan 1, 2017

By T. W. Camm, J. C. Johnson, S. D. Rosenthal

"Most engineers are bright, hard-working, reliable and prefer to avoid conflict. An engineering curriculum tends to self-select these characteristics. By most standards, you would expect workers exhibiting these traits to require minimal supervision. But, is this true? Is this how most current engineering managers lead? Looking at some current theories on leadership combined with personal anecdotes, this article will look at some common misconceptions about leading engineers.Engineers are different. There, it has been said. From cartoons to movies to television shows and more, there is a reason stereotypes of engineers resonate. Yes, you can find a lot of individual variation among specific engineers that you may know, but they do not detract from some of the overarching commonalities that engineers are known for.Clash of culturesWhat distinguishes a professional? Raelin (1985), in his book Clash of Cultures, describes professionals as having superior intellectual training, maintaining their own standards of excellence and being supported by associations that maintain the quality of the profession. Engineers obviously fit all three of these ideas: an engineering degree is still regarded as one of the most difficult to attain. Standards are maintained both through peer review and in academia, through ABET accreditation and through professional associations like SME to promote the discipline and foster technical growth.Six characteristics representing professional status are described by Raelin (1985, p. 9):• Expertise — prolonged specialized training in a body of abstract knowledge.• Autonomy — the freedom to choose the means to solve a problem.• Commitment — primary interest is in pursuing the practice of one’s own chosen specialty.• Identification — identifying with the profession and with fellow professionals, both through formal associations and through peers external to the organization.• Ethics — providing service without concern for oneself or without becoming emotionally involved with the client.• Standards — committed to help in policing the conduct of fellow professionals."

Jan 1, 2018

By William S. Eaton

Managing a mine or mineral processing operation in today's environment presents many unique challenges to mining companies. In recent years, headlines around the world have publicized major incidents such as those associated with the Marcopper Mine in the Philippines, the cyanide release in Guyana from the Omai gold mine and numerous other mishaps associated with mining. These notable upsets were due to engineered system failures, either during normal operations or as a result of uncontrollable events. There fore, many mining firms are attempting to assess their overall risks and establish some priority for expenditure of limited operational and environmental budgets. Failure of an engineered component can have dire operational consequences that affect profitability until repair or replacement can be completed. In addition, there may be significant environmental consequences associated with the engineered system failure. This, too, may affect profitability for an extended time or even the viability of an operation. An engineered risk assessment (ERA) can support a mining company's efforts to cost effectively manage environmental risks associated with the operation of its facilities. The ERA approach also provides information about the current condition of engineered systems. This ERA approach provides a systematic review of the risks of an engineered system failure and the possible associated environmental consequences at mining company facilities. This approach has been successfully applied to many industries and types of engineered systems (Barneich et al, 1996; Whitman, 1984; Power and Tomkins, 1974; Keeney, Nair, and Kulkarni, 1979). This approach evaluates all mining and mineral processing facilities located at a single site and compares them with similar facilities located at multiple mine sites. The ERA approach has been applied to a mining, milling, smelting, leaching and refining operations. These assessments can be part of a comprehensive environmental program to aid in the recognition and cost effective management of the potential environmental risks associated with the operation of facilities. ERA results support plan-

Jan 1, 1997

By J. F. Dresser

Managing environmental compliance at a complex facility has the potential to bring a high degree of personal and professional satisfaction to both the corporation and the individuals responsible for day-to-day operations. The decade of the 1990's, however, has seen the emergence of a nationwide trend of aggressive federal and state civil and criminal enforcement for environmental violations. This trend, spearheaded by the U.S. Department of Justice (DOJ) and the U.S. Environmental Protection Agency's (EPA) Office of Enforcement, has the potential to place the corporation, its corporate officers, and compliance personnel at collective professional risk, as well as a growing tendency to place accountability on individuals. Management of environmental compliance has been anecdotally compared to a shooting gallery at a carnival, with the following exception: At the shooting gallery, successfully hitting nine out of ten targets usually brings a reward and recognition of shooting skill; hitting nine out of ten environmental compliance expectations not only brings agency consternation and negative publicity, but the "gallery" will likely shoot back with stiff fines and possible criminal allegations. Faced with the challenges of the new environmental compliance shooting gallery, corporations and professionals are often left asking themselves, "How do we (or more appropriately, can we) win at this game?" This paper examines recent federal enforcement statistics and offers several suggestions for coping with the responsibility of managing environmental compliance in the 1990's.

Jan 1, 1992

By D. M. Anderson

The current mine closure process is faced? with the formidable challenge of controlling environmental and legal liabilities that are associated with mine closure. The current level of environmental statutes and regulations, and the legal/liability considerations, has evolved through regulatory enactment of mine reclamation laws and other existing environmental laws, such as the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). Management tools and techniques to limit risk exposure and financial losses should be employed as an active measure throughout the mine life, including closure and post-closure.

Jan 1, 1995

By J. A. Botín

Investment decision for large mining projects imply an enormous financial risk and therefore, require a more complex risk evaluation methodology taking into account all sources of uncertainty from each process in the project value chain. Generally, the main sources of risk are those related to uncertainty on grade and other techical variables of the orebody. In this study, conditional simulation is applied to develop a risk management model to quantify and to manage financial risk associated to uncertainty on the grade of the orebody. The model was validated in case study on a real porphyry copper orebody in Chile.

Feb 23, 2014

By · J. B. Boisvert, O. Leuangthong, T. Acorn

Optimizing final pit limits for stochastic models provides access to geologic and economic uncertainty in the pit optimization stages of a mining project. This paper presents an approach for optimizing final pit limits for a highly variable and geologically complex gold deposit. A heuristic pit optimizer is used to manage the effect of geological uncertainty in the resources within a pit shell with multiple uncertainty rated solutions. The uncertainty rated pit shells follow the meanvariance criterion to approximate the efficient frontier for final pit limits. Stochastic dominance rules are then used in a risk management framework to further eliminate sub-optimal solutions along the efficient frontier. This results in a smaller set of final pit shells that could be further analyzed for production scheduling. Additionally, the original solutions are analyzed for changes in the mining limits and two regions are targeted as potential regions for further exploration.

By · J. B. Boisvert, O. Leuangthong, T. Acorn

Optimizing final pit limits for stochastic models provides access to geologic and economic uncertainty in the pit optimization stages of a mining project. This paper presents an approach for optimizing final pit limits for a highly variable and geologically complex gold deposit. A heuristic pit optimizer is used to manage the effect of geological uncertainty in the resources within a pit shell with multiple uncertainty rated solutions. The uncertainty rated pit shells follow the meanvariance criterion to approximate the efficient frontier for final pit limits. Stochastic dominance rules are then used in a risk management framework to further eliminate sub-optimal solutions along the efficient frontier. This results in a smaller set of final pit shells that could be further analyzed for production scheduling. Additionally, the original solutions are analyzed for changes in the mining limits and two regions are targeted as potential regions for further exploration.

By J. B. Boisvert, O. Leuangthong, T. Acorn

Optimizing final pit limits for stochastic models provides access to geologic and economic uncertainty in the pit-optimization stages of a mining project. This paper presents an approach for optimizing final pit limits concurrently over all realizations in a stochastic model and using a risk-management framework to manage the geologic and economic uncertainty. A heuristic pit optimizer is used to find multiple uncertainty-rated pit shells. These uncertainty-rated pit shells follow the mean-variance criterion to approximate the efficient frontier for final pit limits. Stochastic dominance rules are then used in a risk-management framework to further eliminate suboptimal solutions along the efficient frontier. This results in a smaller set of final pit shells that can be further analyzed for production scheduling. Additionally, the original solutions are analyzed for changes in the mining limits, and two regions are targeted as potential regions for further exploration.

By D. R. Willmer, E. J. Haas

As national and international health and safety management system (HSMS) standards are voluntarily accepted or regulated into practice, organizations are making an effort to modify and integrate strategic elements of a connected management system into their daily risk management practices. In high-risk industries such as mining, that effort takes on added importance. The mining industry has long recognized the importance of a more integrated approach to recognizing and responding to sitespecific risks, encouraging the adoption of a risk-based management framework. Recently, the U.S. National Mining Association led the development of an industry-specific HSMS built on the strategic frameworks of ANSI: Z10, OHSAS 18001, The American Chemistry Council’s Responsible Care, and ILO-OSH 2001. All of these standards provide strategic guidance and focus on how to incorporate a plan-do-check-act cycle into the identification, management and evaluation of worksite risks. This paper details an exploratory study into whether practices associated with executing a risk-based management framework are visible through the actions of an organization’s site-level management of health and safety risks. The results of this study show ways that site-level leaders manage day-to-day risk at their operations that can be characterized according to practices associated with a risk-based management framework. Having tangible operational examples of day-to-day risk management can serve as a starting point for evaluating field-level risk assessment efforts and their alignment to overall company efforts at effective risk mitigation through a HSMS or other processes.

Jan 1, 2016

By Scott E. Broughton, Robert T. Tape

Heap leaching requires containment and storage of cyanide solutions, the volume of which may increase dramatically following an extreme storm event or extended wet periods. This paper describes a computer operated solution storage model developed to assist in the management of these requirements. It results from the accumulative efforts of various Klohn Leonoff engineers working on a number of heap leach projects throughout the western United States for the past several years.

Jan 1, 1988

By Karoly C. Kocsis, Kyle A. Scalise, Marcelo Bandeira Teixeira

Understanding the effects of various ventilation and climatic parameters on the work conditions and comfort in underground mines is critical for efficient ventilation system design and cost savings and to ensure the health and safety of mine workers. To understand the effects that the thermal damping effect (TDE) and the thermal flywheel effect (TFE) have on the ventilation system design and potential cooling system, this paper compares and analyzes the wet and dry-bulb temperatures at the bottom of an intake shaft using two modeling software packages, Ventsim™ and Climsim™. The comparison shows the consequences and importance of taking into account the TDE/TFE when predicting the climatic conditions in future underground mines, especially when deciding on whether a cooling system should be employed in order to provide adequate climatic conditions in the production stopes, dead-end development headings, and throughout the mine. Ventsim™is able to account for the TFE, while Climsim™does not. Both software packages have their uses and are used within the mining industry, but it is useful to understand their limitations and where the future of underground climatic modeling will lead.

Oct 9, 2020

By Philip Weaver

The MIDAS project is funded by the European Commission (DG Research) and began on the 1st November 2013. The project will investigate the environmental impact of deep-sea mineral and energy extraction: specifically, polymetallic sulphides, manganese nodules, cobalt-rich ferromanganese crusts and the potential mining of rare earth elements. As deep-sea mining becomes ever closer, and the International Seabed Authority begins to develop its regulatory framework for exploitation of deep-sea minerals, MIDAS is well timed to provide fundamental scientific information. The MIDAS partnership represents a unique combination of scientists, industry, social scientists, legal experts, nongovernmental organisations and small and medium enterprises. MIDAS is carrying out research into the nature and scales of the potential impacts of mining including 1) physical disturbance of the seabed by mining, the creation of mine tailings; 2) the potential effects of particle-laden plumes in the water column, and 3) the possible toxic chemicals that might be released by the mining process. Key biological unknowns, such as connectivity between populations, impacts of the loss of biological diversity on ecosystem functioning, and how quickly the ecosystems will recover will all be addressed. The plan is to use this information to aid development of recommendations for best practice in the mining industry. A key component is the involvement of industry within the project and through stakeholder engagements to find feasible solutions. The project will work closely with European and international regulatory organisations to take these recommendations forward into legislation. A major element of MIDAS will be to develop methods and technologies for 1) preparing baseline assessments of biodiversity, and 2) monitoring activities remotely in the deep sea during and after exploitation, including ecosystem recovery. To carry out this work MIDAS is conducting a number of research cruises to examine the above issues at potential sites for exploitation of SMS and nodule deposits. This talk will present some of the recent findings of the project.

Sep 1, 2014

By James W. White

From Modular's first truck-dispatching system for Phelps Dodge Corporation in 1979 to today's alliance between Modular and Komatsu, Ltd., innovation has been Modular's main product. This paper describes the growth of a mining products supplier and the philosophy and decisions behind that growth.

Jan 1, 1998

By Robert C. Schenk

The rapidly expanding, globally based mining industry provides many opportunities and challenges for the engineering construction business. This paper reviews some of the innovations that the industry is implementing to provide increased value in the design, construction, and successful start-up of new mine plant facilities. Approaches being taken to reduce installed-plant costs as well as related value-enhancement opportunities are discussed. Included are comments on new technology developments, use of automation and global communications networks, application of economic models as a project design tool, and management approaches being adopted to make the engineering construction process significantly more effective.

Jan 1, 1998

By A. Hoath, V. Paul, F. Haslam McKenzie

This paper considers mining ventures occurring in rural communities in Galicia, Spain and Western Australia, Australia. It compares and contrasts the communities where mining is taking precedence over other industries, examining the potential land use conflicts and the future of both the communities and the mines currently operating there. The Galician case study, Trevinca, is located 200 km inland and was once a primary producing area, notable for its scenic alpine landscapes, which have since been developed for small scale tourism purposes. The Australian case study, Boddington is located 100 km inland in what has been a highly productive farming area. Mining was a marginal industry in the case study areas but due to the comparative devaluing of agriculture and tourism and the increased value of mining outputs, mining has increased in scale and economic importance. This paper will consider the environmental, social and economic impacts that have occurred in both the case study localities. Where there have been land use conflicts, strategies for minimising the adverse outcomes will be considered.

Jan 1, 2011

By M. C. Baumann

The Getchell Mine is located in Humboldt County, Nevada, approximately 70 km northeast of Winnemucca. Slope management has been a critical factor in the feasibility of mining operations since they began in the early 1930's. Although underground entries began in 1937, underground production was limited because hanging walls consisting of clay gouge and crushed rock tended to collapse into the workings. Controlling these collapses required extensive timbering. Due to these poor ground conditions, surface open-pit mining was the primary mode of production from 1938 to 1967 with only minor contributions from underground operations. Mining was suspended in 1967 due to economic pressures. From 1960 to 1967, the previous operator mined the property in three open pits. Initially, these pits were constructed with footwall benches, but these failed. These failures were aggravated by construction of 60° slopes in footwalls with shale partings dipping into the pit at 43° to 60°, resulting in large planar failures and wedge failures. In response, the previous operator adopted a slope parallel to the bedding planes.

Jan 1, 1993

By S. Culp, P. Metcalfe

Web technologies and the Internet have revolutionized the computer industry. The Web browser technologies have also moved to portable devices such as Personal Digital Assistants (PDAs) and mobile phones. This paper looks at how to implement a Web Server solution and addresses some of the inherent advantages in the technology. It will also look at some examples of how plant productivity can be managed with a Web Server approach.

Jan 1, 2002