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By J. R. Heberger

"“Safety Pays in Mining” web application developed by the U.S. National Institute for Occupational Safety and Health Mining Program, helps mines determine the potential costs associated with mining injuries. This web app groups injuries by type, either by the cause of the injury or by the nature of the injury. When the user selects one of more than 30 common types of mining injuries, the app provides information on the distribution of costs of workers’ compensation claims for that type of injury. Based on other user inputs, the app will estimate the total costs of the selected injuries, including an estimate of additional indirect costs, the estimated impact of total injury costs on mining company profits, and provide some examples of other items, such as services or equipment, on which companies could spend the savings that result from the prevention of injuries. This paper reviews the app by discussing its development, how it is used to show the true costs of mining injuries, and how mines can benefit from using it.IntroductionInjuries on the job cause pain and suffering. They can also profoundly affect profits and daily operations. In addition to paying direct costs or increased premiums for workers’ compensation insurance, a company might need to pay overtime for other workers to fill an injured worker’s job role, cover training costs for a replacement worker or divert administrative resources in the wake of an injury. “Safety Pays in Mining” is a web app that estimates the distribution of these injury costs and assesses the impact that occupational injuries have on a company’s profits.The costs of specific types of occupational injuries in mining are not readily available as mining and insurance companies do not usually share this information. As a consequence, companies only have cost information based on previous experience with their own employees. Therefore, if a mine never experienced a finger amputation for one of its miners, for example, it would not be aware of the possible costs associated with this type of injury. In addition, injury costs are unique in that the cost distribution is so wide that just using the average cost of a specific injury type does not provide adequate information. Some injuries involve immensely high costs, and even though the risk of these high-cost injuries occurring is low, mines need to be aware of the potential impact on their company’s financial health."

Dec 1, 2018

By M. Wickham

Design of an open pit backfill requires an understanding of highly varied processes including slope stability, hydrogeology, pit lake chemistry, climate, runoff, and mine waste behavior. Dynamic systems modeling (DSM) provides flexibility to the designers of open pit backfill, allowing them to directly integrate many different physical processes and varying levels of complexity. DSM also provides for the efficient application of uncertainty analysis to define a range of possible results, the sensitivity of the results to uncertainties in model inputs, and the value of additional data. This paper presents the results of an analysis using DSM to evaluate a pit backfill design at an Arizona mine. The objective of the partial backfill was to stabilize an active slope that threatened facilities adjacent to the pit. DSM was used, in part, to develop a pit lake water balance model for evaluating the influence of the backfill on the ability of the pit to maintain passive hydraulic containment of groundwater and surface water inflows and for evaluating costs for various backfill scenarios.

Jan 1, 2001

Ceremonies for the induction of four mining industry pioneers into the National Mining Hall of Fame will be held Saturday, Sept.9, 2006 at the Museum Convention Center in Leadville, CO. The four inductees are Earl H. Beistline (1916 to present), R.A.F. Penrose (1863-1931), Robert M. Reininger (1912-2006) and John Stanton (1830-1906). The inductions will bring to 193 the number of mining “greats” whose engraved photographs and biographical sketches are installed in the National Mining Hall of Fame.

Jan 1, 2006

By Donald Hulse

"Mining has been a source of controversy for at least 500 years. “Since there has always been the greatest disagreement amongst men concerning metals and mining, some praising, others utterly condemning them…” (Agricola, 1556). In 2016, it is widely recognized that mineral resources and reserves must give due regard to the social license in order to operate.“Most commonly, the social license to operate (SLO) is understood to refer to ‘the ongoing acceptance and approval of a [project] by local community members and other stakeholders that can affect its profitability’ (Moffat, 2014).” “Social License to Operate has gained traction, in part, because it is also a concept which – while remaining poorly, technically defined – is generally easily and widely understood by community stakeholders (Bice, 2014).”A generation ago we learned that mining is based on a stable platform supported by three pillars, geology, mining and metallurgy. The three-legged stool is a very stable structure (Fig. 1).In 2016, it seems that we have added some other legs to the stool (Fig 2). The Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves (JORC Code) addresses “social, and governmental factors…” (JORC 2012), and refers specifically to social license in Section 4 of the Report Template “Estimation and Reporting of Ore Reserves.”The Canadian Institute of Mining, Metallurgy and Petroleum (CIM) Guidelines refer to “environmental, legal and social data…(CIM 2003).”Compared to these, the 2014 SME Guide is positively verbose stating “a discussion of any potential social or community related requirements and plans for the project and the status of any negotiations or agreements with local communities,” (SME 2014) although in all cases the scope of this disclosure is left at the discretion of the competent person.When there are more than three legs on the stool, it is imperative that all legs be constructed exactly to the design. Any one or more legs that are out of alignment will cause the stool to wobble.Engineers are trained to create designs to meet specifications. Loads can be estimated, forces calculated and cost studies completed that will lead to, not only a stable design, but the most efficient design that meets the specifications."

Jan 1, 2015

By Steve Kral

Good times make for happy miners. And the past few years have seen a lot of smiling mining engineers, geologists, metallurgists, corporate executives, analysts, investment bankers and shareholders. And nowhere was that more evident than at the 74th Prospectors and Developers Association of Canada’s (PDAC) annual meeting. The meeting, held in Toronto March 5-8, attracted a record 14,500 people. Of those, the PDAC said attendees came from an estimated 100 countries. And about 40 countries sent national delegations to the meeting. Argentina, for example, sent nearly 100 people. The PDAC meeting has always been a event where companies and individuals can get a look at numerous properties in all parts of the world that could potentially become major mines. And through the many receptions, hospitality suites and just sitting in the local restaurants and taverns, deals are usually made.

Jan 1, 2006

By D. Sohn

Work accidents have an essential impact on the economy of a country and in final consequence on each company. The main purpose of industrial OHS is to maintain and promote the health of all employees. Healthy working conditions increase efficiency and motivation and safeguard the success of the business against the background of the extremely dynamic processes of change. Maintaining and promoting the health of all employees, weather in operation, administration or on the mining site, has become therefore not only an ethical requirement but also an economic must. Creating a suitable working environment for people today entails much more than just preventing accidents and work-related illnesses. It is important to be proactive in establishing an even better culture of prevention and to convince everyone, workers and managers alike, of its importance. Especially in the age of rapid changes and above all in view of global competition we are more dependent than ever on healthy, enthusiastic, competent and creative employees. OHS provides you with the necessary competitive edge.

Jan 1, 2007

By O. F. Brown

The use of quality materials (aggregates and asphalt binder) in optimal proportions is the key to producing optimally performing hot mix asphalt (HMA). The Superpave mix design standard in the US introduced specific volumetric and binder property requirements in HMA design. Different methods for HMA constituent proportioning have been proposed in various guidelines. The design process to determine the HMA blend is currently iterative and engineers rely almost exclusively on experience. This approach is time consuming and often does not result in cost-optimal HMA mixtures. This paper introduces a mixed integer linear programming (MILP) optimization model for hot-mix asphalt constituent proportioning. The MILP model minimizes the total mix cost while satisfying all the volumetric, binder and mix property specification requirements. The model has been successfully validated with real-life example. The aggregates and binder ratios from the model were in close agreement with those from the contractor. The Bailey ratios and the gradation constraints were also satisfied. The cost of the optimal mix was $0.804/Mg less than that of the contractors?. This marginal reduction might make all the difference in an industry that is highly competitive. The MILP model also demonstrated that adding RAP to the contractor?s design would reduce the cost of the blend by $5.74/Mg. The virgin binder content was reduced by 1% because of the recycled asphalt contained in the RAP. This work represents the first successful attempt in incorporating both aggregate and asphalt performance requirements into the optimization formulation. Applying these models will ensure the minimum cost mix that meets all constraints and will increase profit margins for plant operators.

Jan 1, 2012

By R. Gensemer

A number of state and federal agencies are calling for development of aquatic life criteria for conductivity. These aquatic life criteria or ?benchmarks? are based on observed correlations between conductivity and benthic macroinvertebrate community composition, generally measured by composite metrics or indices. However, development of an aquatic life criterion for a composite variable like conductivity is made difficult by a number of factors. Based on a database from West Virginia, observed patterns of invertebrate community composition versus conductivity may instead be related to a combination of abiotic (e.g., ionic composition, habitat) and biotic (e.g., life history, colonization potential) factors. Many benthic invertebrate taxa also do not respond to increasing conductivity in a consistent relationship. Many states have determined that a composite variable, like conductivity or TDS, is not appropriate for criteria development, as many studies have shown that toxicity varies as a function of ion composition and can be mitigated by elevated hardness. We conclude that the relationships between conductivity and changes in benthic macroinvertebrate community composition are neither strong nor reliable enough to warrant derivation of a criterion based solely on conductivity.

Jan 1, 2011

In this paper, a mixed integer linear programming (MILP) model for the short-term scheduling of open pit mines is formulated. The proposed model aims at sequencing the blocks extraction over multiple short-term periods. The model takes into account multiple processes, waste dumps, and multiple stockpiles. The short-term scheduler makes a decision on the period, destination, and route that ore and waste are supposed to take to minimize costs while meeting all the mining and processing constraints. The destinations of the extracted materials are also controlled by their rock types. A monthly short-term production scheduling case study of an iron ore deposit is carried out over a year to validate the model.

Jan 1, 2011

To simplify programming, image analyzers commonly measure either linear intercepts or the areas of particles and grains to determine liberation based on polished section mounts. However, the concentration of minerals by flotation is based on reagents that interact with the exposed surfaces of the minerals. Thus, it is often perceived that image analyzers should measure the perimeter of the mineral of interest in the ore particles. A comparative liberation study of thirteen samples collected from a flotation plant processing a complex base metal sulfide ore showed that the liberation of the ore minerals determined by area measurements is very similar to the liberation determined by the exposed perimeters. The liberation determined by exposed perimeters is more appropriate only for those cases where the mineral texture is so complex that it is retained in the small particles generated in conventional grinding operations.

Jan 1, 2002

By J. Kretschmann, O. Drusche, S. Krause

Mining companies are caught between the growing international relevance of ESG (Environmental, Social and Governance) investments and the need to secure their “social license to operate” by considering the needs of their stakeholders. In the search for sustainable business models, the concept of the circular economy (CE) is gaining momentum among practitioners and scholars, as it enables the creation of shared value and thus strengthens the trust of investors and stakeholder relationships. However, there is a lack of a sectorspecific CE framework providing guidance to decision-makers in evaluating promising activities. A gap, which this contribution aims to address.

Mar 2, 2022

By I. Loomis, D. Rachmad, I. Duckworth

During the past two years the Underground Mine Ventilation Group at PT Freeport Indonesia has undertaken to upgrade their Hygiene Laboratory. This process has included upgrading equipment for dust sampling and gas monitoring, as well as procurement of an OCEC analyzer for Diesel Particulate Matter analysis. While the laboratory equipment represents one factor, these changes have also required re-evaluation of the sampling protocols and the burden of ventilation monitoring personnel. This paper provides a review of these experiences.

Jan 1, 2006

The MINER Act of 2006 mandated that all underground coal mines must install and maintain refuge chambers. Refuge chambers serve as a temporary shelter in case of emergency. Several factors affect the performance of a refuge chamber: heat production inside the chamber and introduction of CO when chamber doors are opened are two major factors. This study examines the CO purging process and to determine total air quantity and time necessary to lower the CO con-centration to safe levels for different inlet/outlet configurations using three-dimensional simulation technique. The study uses Reynolds Averaged Navier Stokes and continuity equations along with the spe-cies transport model assuming uniform air mixing. The heat transfer of any kind is neglected and the purging process is assumed to take place isothermally. The standard k-e model is utilized for simulating turbulence in the flow field. This research provides useful guidelines in developing an efficient strategy for purging refuge chamber. Keywords: Airlock chamber, Purging, Carbon monoxide, Turbulence

Feb 27, 2013

By Zoë Mullard

The introduction of Web 2.0 platforms (also referred to as social media), with their architectures of participation, has ushered in a new era of technological interaction and information exchange that is changing the nature of corporate-community communications. Web 2.0 platforms give users the ability to generate data collaboratively, meaning that more stakeholders maintain the expectation of being able to contribute to online dialogue. In light of these changes, it is important for business to consider how social media can be used strategically to enhance stakeholder relationships and increase business efficiencies. This article provides three case studies of how different stakeholders in the mining industry are strategically using Web 2.0 platforms to communicate with target audiences. The case studies are based on the experience of respondents and from website observations, which were undertaken as part of a thesis research project by the first author (Mullard, 2010), focusing on the application of social media in the mining industry.

Jan 1, 2011

By R. Hardy

LaModel is a boundary-element program capable of calculating the displacements and stresses in thin bedded deposits such as coal, salt, or potash. Throughout its history, it has continually been upgraded in order to expand analysis detail and stay current with the latest advances in computer technology. The most recent enhancements include: an increased grid size capability, a significant increase in the speed of the automatic grid generation using an AutoCAD visual interface, implementation of subsidence-based horizontal strain calculations for multiple-seam situations, and pillar safety factor calculations. To demonstrate these new features, a multiple-seam case study of a longwall panel undermining an active set of main entries is presented.

Jan 1, 2006

By S. Assemi

Interaction forces between a hydrophilic silica particle and an air bubble were measured by atomic force microscopy using simplified model systems with deionized water and dilute KCl solutions. Contributions from the hydrodynamic force were minimized by using a low piezo speed. Particle-bubble separation distance and the bubble spring constant were calculated from linear regression of the piezo extension versus cantilever deflection. The bubble surface potential was then estimated from fitting the AFM-measured forces to the Hogg-Healy-Fuerstenau (HHF) model, using the surface element integration (SEI) method. Surface potentials obtained for the bubble at a low applied force were comparable with the literature data, suggesting that the simplified model used here can give a reasonable estimation of the bubble surface potential under moderate applied forces. Interaction forces between a silica particle and an air bubble were also measured at different locations on the air bubble surface. The force curves obtained at the edges of the bubble fitted very well to the theoretical force curves regardless of the applied force, while curves obtained at the center and halfway to the center, were more difficult to fit, in particular at higher applied forces (> 13 nN), suggesting that force curves obtained at the edges of the air bubble might be less prone to deformation effects.

Jan 1, 2008

By W. X. Wang

In the mining and quarry industries, rock fragments are often transported by conveyor belt. To estimate the qualities of the rock fragments (i.e., size distribution and shape), an operator must take samples from the conveyor and manually perform a sieve analysis, which is time-consuming and tedious. Alternatively, an image-analysis system can be used to monitor the fragment quality on a fast moving conveyor belt. However, images of fragments on a fast moving belt vary to such a degree that the quality of any two successive images are not the same, and some of the images are of such poor quality that they are unrecognizable by human eyes. If poor-quality images are directly analyzed by a segmentation algorithm, the analysis will not be satisfactory. To resolve this problem, it is necessary to use an image-classification pro-gram for the automatic selection of fragment images with good quality. Because of this need, an image-classification program was developed and tested both in the laboratory and in the field. Testing of the system on different types of fragments showed that the system works reasonably well.

Jan 1, 1996

By C. C. Clark

The national Institute for Occupational Safety and Health (NIOSH), Office of Mine Safety and Health, Ground Control Engineering Branch is investigating the use of shotcrete in weak rock mass mines with the objective of reducing fatalities and injuries resulting from rock fall accidents. When shotcrete is used as part of a multi-element ground support system, it is necessary to know when the material has developed a compressive strength of approximately 1 MPa (145 psi), the early threshold for safe re-entry of miner and machine into shotcreted mine workings at this value, the material has developed enough strength to be self-supporting and to allow for installation of other ground support components that require drilling of the shotcrete layer without degradation. NIOSH researchers have developed methods and portable test equipment to measure shotcrete strength on site in the first six hours after application using a partial beam test standard, a STM C 116-90 (1990). These advances were demonstrated in tests with five commercially available shotcrete mixes, sprayed as dry shotcrete using field expedient methods and equipment. The strength values from these tests allowed for real-time identification of the early strength threshold and were consistent with strengths reported using laboratory-type equipment. Measuring the early strength properties of shotcrete directly at the mine site can improve mine safety by identifying appropriate re-entry times and providing a convenient means of conducting on site quality control during shotcrete applications.

Jan 1, 2011

By Raquel Costa, Aldino Campos, Frederico Carvalho Dias, Pedro Madureira, Patrícia Conceição, Ana Filipa Marques, Andreia Afonso, Maria Ana Martins, António Calado, Luísa Pinto Ribeiro

Since its formation in 2004, the Task Group for the Extension of the Continental Shelf (EMEPC) has been collecting hydrographic, geological and geophysical data to support the extension of the continental shelf beyond 200 NM. In 2008, the EMEPC acquired a 6,000 m rated ROV named "Luso" and has been cooperating with several national and international institutions to increase and improve its operational capabilities to conduct research on deep-sea minerals. The Portuguese continental shelf corresponds to a broad area of the seafloor encompassing different physiographic domains: the mid-Atlantic ridge system, abyssal plains and numerous seamounts. From 2008 to the present, the mid- Atlantic ridge and seamounts have been the most visited sites with the ROV "Luso". Several hydrothermal vent sites are known to occur along the mid-Atlantic ridge to the south of the Azores archipelago and mostly within the Portuguese EEZ. Vent fields were also discovered in the extended continental shelf, namely the Rainbow and the Moytirra sites located to south and to the north of the Azores archipelago, respectively. The most studied seamounts correspond to those forming the Great Meteor chain and the Madeira- Tore rise. All these visited sites are related either with the occurrence of polymetallic sulphides or cobalt rich Fe-Mn crusts and the opportunities to further pursue their exploration will be discussed.

Sep 1, 2014

By A. Nivala, S. Ulgiati, M. Canino

Mining and processing of bastnaesite ore, (Ln)CO3F, for lanthanides extraction is investigated in this paper. This series of elements proved to be applicable for a wide range of high-tech uses. In spite of the strategic importance of lanthanides, no LCA and energy analyses of their extraction have ever been published. We perform in this paper a Life Cycle Assessment of the Lanthanide production cycle, based on available database and literature data from Mountain Pass mine (USA) and other worldwide mining and processing sites, most of which in China. We investigated three main steps: mining, milling (including transport, grinding and drying), and flotation (for lanthanide chloride extraction). We do not investigate here the separation of pure oxides from lanthanide chloride, a compound which is also marketed as such. The conventional LCA was integrated by means of energy and emergy evaluations, aimed at investigating respectively the global energy cost and the environmental sustainability of the process. Indicators of material intensity, thermodynamic efficiency, and environmental impact (including LCA and ecological footprint impact categories) are calculated and discussed.

Jan 1, 2005