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The 26th international APCOM symposium, hosted by The Pennsylvania State University, was held Sept. 16 to 20, 1996 in University Park, PA. Conducted about every 18 months throughout the world, APCOM symposia focus on the Application of Computers and Operations Research in the Mineral Industry. The APCOM International Council is the governing body of the symposia and determines the symposium’s locations and sponsorships. This group is composed of the nine permanent (voting) members. They include the University of Arizona, Colorado School of Mines, Pennsylvania State University, Society for Mining, Metallurgy and Exploration, Inc., Canadian Institute of Mining, Metallurgy and Petroleum, South African Institute of Mining and Metallurgy, Technical University of Berlin, Institution of Mining and Metallurgy and Australasian Institute of Mining and Metallurgy. The three nonvoting members are Moscow Mining Institute, China Institute of Mining and Rudarski Mining Institute of Slovenia.

Jan 1, 1996

By C. R. Tinsley

Investment activity in the Pacific Rim of Fire has seen a phenomenal surge from epithermal gold exploration. Individual countries are attractive because of lower up-front minerals lease costs (US, Canada), better geological prospectivity (Chile, Indonesia), or cheaper equities (Australia). Since the October 1987 stock-market crash, large companies are shedding minority joint venture interests to focus on core businesses. Some vertical integration is evident in Japanese coal investments in the Pacific Rim. This paper does not cover the aluminum industry oligopoly which is multi-national in character nor does it cover the many Canada to US minerals investments. It will be interesting to see if the new US-Canadian free-trade treaty will reverse that investment flow.

Jan 1, 1990

By N. L. Dorset, K. L. Heasley

Unfortunately, mining and mining accidents have gone hand-in-hand since man first started to extract ore from the ground. In the first published treatise on mining, De Re Metallica, Georgius Agricola (1556) stated that cold, water, dust, stagnant and foul air, roof falls, falls from ladders and demons all caused injury and death in the mines of his day. Although demons are no longer considered a cause of accidents in modern mining, the other factors remain with us still. The United States government started keeping track of fatalities with the establishment of the federal Bureau of Mines in 1910. Successor agencies, such as the U.S. Mine Safety and Health Administration (MSHA) continue to track fatalities today. Looking at the records, it can be seen that coal mine fatalities dropped from 2821 in 1910 to only 27 in 2004. The reduction in fatalities and injuries didn’t “just happen.” It took concentrated effort from the entire mining industry: miners, supervisors, safety officials, mining inspectors and mining researchers. But first, specific hazards must be identified before they can be corrected. In past, coal mining accidents have been analyzed by: type (roof fall, electrical, etc), mine attribute (location, seam height, etc.), and aspects of the mineworker (work experience, job classification, etc). Much of this research helped to direct the industry’s attention to where additional vigilance and safety training was needed. No doubt this directed effort has led, at least in part, to the decrease in coal mining fatalities. This paper takes a novel look at coal mining fatalities: it examines the risk of fatalities based on how long the mine has been open.

Jan 1, 2006

By K. Park, J. Sohn

Recovery of industrially useful metals from various secondary sources is an important issue in Korea whose natural resources are limited and needs in the strategic metals are on the rise. In order to meet such needs, researchers at the Korea Institute of Geoscience and Mineral Resources have launched a number of projects to help the nation to recover various metals from secondary sources. In this study, silver is successfully recovered from spent silver-oxide batteries first by distillation to remove mercury. The distilled residue was next subjected to leaching of silver using nitric acid. The study involves finding optimum conditions to leach silver from the distilled residue and subsequently to recover silver from the leach liquor by chemical precipitation. The chemically precipitated products are then subjected to reduction roasting to recover silver metal.

Jan 1, 2002

By Kai Wang, Chao Xu, Qiang Fu, Tong Yang, Chunyu Zhao, Wei Zhao

The stress of a coal seam is an important factor that affects the permeability of the coal seam and then affects the coalbed methane (CBM) drainage. In China, adjacent coal seam mining is an important method to reduce stress, which increases the permeability of the coal seam. However, in the process of mining adjacent coal seams, many coal pillars remain, which causes stress concentrations and results in a decrease in permeability. Therefore, it is important to study the influence of coal pillars on the stress of adjacent layers and its distribution and evolution in the floor rock. This paper took the Shendong Baode Coal Mine as a case study and investigated the influence of the coal pillar on the stress and permeability of coal seam #11. The results show that under a coal pillar, the relationship between the vertical stress of different floor depths and the width of the coal pillar can be divided into a negative correlation zone, transition zone, and positive correlation zone. The change in the coal pillar width does not affect the pressure relief range or the degree of pressure relief in the adjacent coal seams below the goaf. The field measurements show that after the mining of panel #81,505, the permeability coefficient of coal seam #11 under the goaf increased from 0.1434 to 26.3545 m2/( MPa2*d), increasing 182.7 times, and the drainage mixing volume of boreholes #1 and #2 increased from 1.24 to 1.52 m3/ min. While the permeability coefficient of coal seam #11 from 12.5 m in the coal pillar has only increased by 2.6 times, the drainage volume of boreholes #3 and #4 did not change significantly.

Nov 19, 2022

By R. L. Derick

On a regular basis, mine personnel should obtain air samples directly from active underground areas as well as remotely from sealed locations. These samples provide mine officials with data relative to the makeup of the various atmospheres. Should conditions underground change, these results can provide a baseline that can assist officials in determining the extent of change. Relating the concentrations of individual gases to time, applying gases to equations, and examining their change over time are tools that have been successfully used to determine if a heating event exists and, if so, the extent of the emergency. These atmospheric status equations have either been developed for the mining industry or adapted from other industries. They serve as tools to assist personnel in determining the condition of underground mine atmospheres. As long as the problem area continues to be ventilated, certain gases, gas ratios, and equations can be used to determine if a fire exists, what type of material could be burning, and what quantity of coal is burning. Once the mine or the involved section has been temporarily sealed, gases, ratios, and gas-derived equations can assist personnel in determining how conditions within the sealed volume are changing over time. To alleviate potential explosions when fresh air is once again introduced into the sealed volume, equations and a diagram have been developed to predict the likelihood of an explosive atmosphere. Similarly, prior to commencing recovery of a mine or section, equations exist that can assist in determining if the fire will rekindle when air is reintroduced. This paper serves as an overview to remind and/or instruct readers about gas-sampling methodologies and gas analyses to assist in determining the status of underground atmospheres.

Jan 1, 2006

By Silas Li, Michael Harris-Gifford, Jason Choi, William H. Hansmire

Twin-bore tunnels with a single track in each tunnel are currently the most common subway tunnel configuration. However, a large diameter single-bore tunnel with two tracks separated by a center wall could replace twin-bore tunnels and introduce potential benefits but require necessary modifications to the subway system. In particular, a nominal 40-foot-diameter single-bore tunnel can be considered in lieu of nominal 20-foot-diameter twin-bore tunnels. This paper discusses the benefits and modifications introduced by replacing twin-bore tunnels with a single-bore tunnel, with respect to various elements of the subway related to the tunnel, stations, track, and tunnel systems.

Dec 1, 2022

By Charles T. Steuart

The Arkansas Novaculite of Devonian and Mississippian age is the most distinctive formation in the central Ouachita Mountains of Arkansas from the standpoint of both topography and lithology. The formation typically forms precipitous, narrow ridges (hogbacks) which reflect the steepness of dip and the resistance and thickness of the rock units. The Arkansas Novaculite varies from less than 200 feet thick in the north to locally over 800 feet thick in the south and outcrops over an east-west distance of 360 km (200 miles) in the Ouachita Mountains of Arkansas and Oklahoma. Most of the rocks of the formation are highly siliceous with novaculite predominating, and lesser quantities of chert, siliceous shale, conglomerate and rarely sandstone. Novaculite is commonly defined as a homogeneous mostly white rock, translucent on thin edges with a dull to waxy luster and composed almost entirely of microcrystalline quartz. The word novaculite comes from the Latin word novacula, meaning razor hone. This term was first used by Richard Kirwan in his mineralogy text of 1784. The origin of novaculite remains controversial but we believe it was a primary silica derived mostly from the alteration of submarine volcanic-rich materials, with numerous fine biogenic components and some minor clastics (derived mostly from foreland facies via turbidity currents) and deposited as an amorphous siliceous ooze in the deep Ouachita trough. It was subsequently converted to microcrystalline quartz during diagenesis by the compaction of the overlying rocks and the intense Late Paleozoic Ouachita Mountain tectonism. In the central and southern portions of the region three divisions of the formation have been defined: a Lower Division predominantly of light-colored novaculite; a Middle Division of interbedded dark chert and shale; and an Upper Division of massive often calcareous novaculite. In the northern exposures the formation is thinner and contains more black chert and shale, chert-shale conglom¬erate, sandstone and less novaculite. The massive novaculite of the Upper and Lower Divisions is a source of high purity silica (99+%). Indians were the first to use novaculite. They made their various tools and hunting implements from the weathered broken rock until they learned the quarrying techniques. The first white men in the area recognized the use of novaculite for sharpening their tools and knives: previously whetstones were obtained in small quantities from Europe. To this day whetstone is quarried mostly in areas which the Indians and possibly the Spanish previously worked. Some of the current mining practices have changed very little from those of the early quarryman. In areas where the novaculite of the Upper Division is poorly cemented, this friable tripolitic material has found applications in such uses as an abrasive, as a filler or extender in paints, plastics and other purposes. Some of the dense novaculite is suitable as a filler in fire bricks and also in plastics. Because some of it has the tendency to decrepitate when heated not all novaculite can be used for these applications. Several quarry operators are crushing novaculite for road, concrete, and other aggregate. This use was formerly rather limited due to the abrasiveness of the novaculite on crushing and screening equipment. Further potential uses of novaculite are speculative but include application of high purity silica in the production of silicon metal for solar cells, seed or "growing", and fusing quartz for electronics.

Jan 1, 1985

By W. Hermülheim, J. Brune

"This paper analyzes mine emergency management and rescue practices in German underground coal mines and compares them to those used in the United States. The German mining industry has developed these practices over more than 100 years, and they have successfully managed numerous fire, water inundation and ground control emergencies using these techniques. The authors interviewed German mine emergency professionals about rescue team and emergency operations. These operations were then analyzed to determine which of these German principles would be of interest to United States mine rescue teams. Implementing these programs into United States mine rescue and emergency operations was analyzed. INTRODUCTION Coal mining has become much safer industry than it has been in the past. Advances in safety and health regulations and company polices have improved working conditions for miners all over the world. Even with these advances there is still a need for continued attention to safety and health. It is also important for mine safety professionals to observe practices and procedures in other countries and cultures and learn what and how to apply this knowledge in their own systems. Coal mine rescue has been an integral part in improving coal mine safety. Mine rescue procedures have evolved with time, experience and technology development. Today, coal mine rescue teams are still needed and must be continually trained and prepared for any mine emergency. Although it is hoped that improved mine safety policies and practices will eliminate coal mine disasters in the future, accidents remind us that disasters can still happen today. In May 2014, Turkey experienced a severe coal mine disaster where 301 people were killed [G.Tuysuz, 2014]. Our industry must learn from these incidents, focusing on disaster prevention and making improvements in mine rescue operations. Mine rescue procedures differ from country to country due different regulatory environments and different historical evolution of emergency response. Sharing practices and procedures from one country to another enables learning from different experiences and cultural backgrounds. Sharing is also a way of preserving information, identifying and learning best practices."

Jan 1, 2015

By Liming Yuan, Wei Tang, RICHARD THOMAS, JOHN SOLES

Lithium-ion (Li-ion) battery pack fires pose great hazards to the safety and health of miners. A detailed experimental study has been conducted at the National Institute for Occupational Safety and Health’s (NIOSH) Pittsburgh Mining Research Division (PMRD) to investigate the effectiveness of different fire suppression systems on Li-ion battery pack fire extinguishment. Tests were conducted in a well-ventilated container. Two sizes of battery packs (12 V and 24 V) were heated by heater strips to trigger thermal runaway and fire. Water mist with different flow rates, ABC powder, type D dry chemical, and water mist with F500 additives were used as the fire suppression agents. Multiple thermocouples were installed on the battery packs to measure the temperature evolution during the tests. The results indicate that the water mist with F500 additives is the most effective suppressant among the agents tested. Dry chemicals, however, do quench the fire for a moment, but cannot prevent re-ignition of the battery since they do not provide enough cooling. The findings of this paper can be used to develop safer battery fire suppression techniques in mining environments.

Jan 1, 2024

By James E. Lawver

At the present time, the Florida phosphate industry is experiencing one of the worst marked slumps in its one hundred year history. Recent agriculture over-production has caused low grain prices such that the net income of U.S. farmers is expected to drop to its lowest level since the 1932 depression. The farmers' low income, along with high interest rates that preclude them from borrowing to purchase fertilizer, make the immediate U.S. phosphate market outlook bleek at best. The export outlook is also pessimistic due to world recession and the U.S. dollar's high exchange rate. In June, 26% of the phosphate industry's workers were laid off for an indefinite period of time. Despite the immediate painful slump, the long-term outlook for the industry looks good. Florida has enormous reserves and will continue to produce a third of the world's phosphate supply simply by making changes in the present system of mining, beneficiation, waste disposal and land reclamation.

Jan 1, 1983

By D. H. Horswill

Red Dog, the world’s largest zinc mine, is located ninety miles north of the Arctic Circle in northwest Alaska on lands owned by the Inupiat Eskimo organization called NANA. NANA received a subsurface title over this resource as part of their settlement lands under the Alaska Native Claims Settlement Act and subsequently entered into a Lease Agreement with Cominco in 1982. Cominco, an international mining company focused on zinc, built and operated the mine. NANA’s principle objective in the development of the mine was to have it contribute to the development of sustainable communities within their traditional region. This meant creating job opportunities in a modern economy while preserving the traditional subsistence lifestyles. Preservation of their culture, language, and traditions are as important to the NANA people today as they were through ages past. The principles of sustainable development – matching economic, environmental, and social goals through continuous communications and high commitment to efficient and effective operations – have been core values for the Red Dog Mine from the beginning. This paper will describe how a large mining operation in a remote corner of the world has been able to contribute toward sustainable development in that region.

Jan 1, 2000

By H. Sevim

In this paper, the research effort in simulating the operation of underground coarse-coal hydrotransport systems (UCCHS) is summarized. The equipment of the system to be simulated is already optimally selected by using an analytical optimization model. The purpose of the simulation model is to test the performance of the system and to obtain the distribution of the operating parameters such as water and power consumption, amount of slurry delivered to the preparation plant, etc. Knowledge of the distribution of these parameters is essential for the efficiency of the design and the operation of the system.

Jan 1, 1985

By C. Hendricks

This paper is based upon field studies conducted in a western Canadian open pit coal mine. This work has involved the adaptation of microprocessor-based instrumentation to monitor various operating parameters on-board blasthole drills and mining shovels. A review of instrumentation and monitoring methodology will first be presented. Based upon experience from field-based studies, the paper will subsequently focus on the application of monitoring technology within the framework of an integrated Equipment Monitoring System. Such a system will permit the real-time performance evaluation of key equipment involved in surface mille production.

Jan 1, 1991

By David Cronan

"Most of the recent renewed interest in manganese nodule mining has been focused in the Clarion-Clipperton Zone (CCZ) in the NE tropical Pacific where nodules are rich in Mn, Ni and Cu. However, equally interesting, but compositionally different, nodules occur in the tropical central South Pacific (CSP). The CC Zone deposits lie in the International Seabed Area whereas those in the South Pacific lie mainly in the Exclusive Economic Zones of Island States, principally the Cook Islands and Kiribati. The CSP nodules should not be regarded as an alternative resource to CCZ nodules, as they are enriched in different elements. Rather, the CCZ nodules should be thought of as a source of one group of metals (Mn, Ni and Cu) and the CSP nodules the source of another group (see below), mutually complementing each other and to be mined in parallel for their different metals.Manganese nodule mining in the South Pacific has been mooted since the 1970s. However, new data on manganese nodule composition and abundance there have recently appeared. Also, a recently developed interest in 'rare', 'green' and 'technology' elements has necessitated a re-examination of old South Pacific nodule data for information on these elements (previously thought to be economically unimportant), and the re-analysis of the deposits to obtain new data on them. Additionally, current and possibly future applications to the UN to extend island 'continental shelf' areas necessitates an appraisal of the manganese nodules in these areas. These developments have prompted recent work that has helped to refine our understanding of the distribution and abundance of metals of traditional interest in South Pacific nodules, namely Mn, Co, Ni and Cu, but has also drawn attention to other elements of possible economic interest including titanium (Ti), vanadium (V) and the rare earth elements (REE)."

Sep 1, 2014

By Harvey Parker

This is part two of an article on the prominent role that the United States and its industry leaders have played on the International Tunnelling and Underground Space Association (ITA), which represents the underground construction and underground space industries worldwide. The U.S. is officially represented in ITA by UCA of SME. (Part one is in T&UC, June 2007, pp 39-42) Tunnel advances in 1960s and 1970s The 1960s and 1970s were active and productive times for the U.S. tunneling industry. During that time, federal programs, sponsored by the Federal Railroad Administration (FRA), the Office of High Speed Ground Transportation (OHSGT) and the Advanced Research Projects Administration (ARPA), stimulated tunnel research and development. Also, the American Society of Civil Engineers (ASCE) and SME collaborated to create the Underground Construction Research Council (UCRC) and the Rapid Excavation and Tunneling Conference (RETC) series.

Jan 1, 2007

By Snehamoy Chatterjee, Dharmasai Eshwar, Aref Majdara, Rennie Kaunda, HUGH MILLER

The U.S. mining industry has made progress in reducing accidents and injuries, but interpreting safety data remains difficult due to changes in workforce size and productivity. The Mine Safety and Health Administration (MSHA) uses tools like the pattern of violation (POV) and significant & substantial (S&S) calculator to monitor safety, though these have limitations. To address this, we developed an information entropybased risk (IER) index that combines various safety metrics, including citations, penalties and injuries. Using data from 2011 to 2020, the IER index was validated with statistical methods and clustering algorithms to ensure it accurately reflects risk levels. The analysis showed clear differences in risk across mining sites, proving the index’s usefulness. The IER index was then applied to a coal mine to demonstrate its effectiveness. This new tool can help mining companies better assess their safety risks and take action to improve workplace safety.

Nov 1, 2024

By Jürgen 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 decarbonization. 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.

By Arash Habibi, Anna Cable, David Loring, Aleksandar D. Bugarski, Logan Ingalls, Calvin Rutter

The results of diesel particulate matter (DPM) monitoring were used by the underground mining industry to mitigate adverse effects of exposure to DPM. NIOSH Method 5040, currently used for ambient and personal exposure monitoring, does not provide needed real-time information. The objective of this study is to develop a methodology for continuous monitoring of DPM concentrations in an underground environment, founded on the application of the Dekati electrical particle sensor (DePS). The DePS, which measures concentrations of submicron aerosol in real time using a diffusion-charging sensor, was evaluated by comparing the results of the concurrent measurements with reference methods at several locations downstream of the diesel-powered equipment. The DePS results were found to correlate well to those obtained by reference methods. However, it was found that dependence of the response on the physical and chemical properties of aerosols necessitates sitespecific correlation factors for the targeted matrices. The site-specific factors for number and mass of diesel aerosols were derived using the results of concurrent measurements with TSI NanoScan, FLIR Airtec, and carbon analyses performed on the concurrently collected filter samples. The results showed that methodology based on compensated DePS measurements would be suitable for continuous monitoring of DPM in underground mining operations.

Dec 1, 2022

By A. S. Macfarlane

Over the last few years, and especially the last few months, issues relating to Corporate Governance in industry in general, and the Minerals industry in particular, have become increasingly topical, as a result of a number of scandals and failures. The development of International and National Codes for the reporting of Mineral Resources and Reserves began some years ago, and has been followed by more stringent Listing Rules for the Securities Exchanges, as well as more standardised formats and protocols for financial reporting of assets and activities. More recently, some countries have adopted Codes for the Valuation of Mineral Properties, which have focussed on standardisation of valuation approaches to be adopted, and the qualifications of people deemed competent to sign off such valuations. This process has not been without criticism, the main criticism being the proliferation of local standards and regulations, which are often difficult to apply and regulate, or which are too prescriptive for multinational mining companies to deal with. In South Africa, these concerns have been recognised, while at the same time a need has been identified to establish a Code which could be applied to South Africa, and the African continent as a whole. Such a development would necessitate that the Code satisfies the needs of the continent, but in a global context. This global context has already been set by the activities of the International Organisation of Securities Commissions, the International Valuations Standards Committee and the International Accounting Standards Board. This paper explains the progress and process that has been established in South Africa for this purpose, and highlights the key issues which are open to public debate, so that the process is inclusive and transparent, whilst at the same time it is consistent with international time frames, and provides a deliverable product that meets the desired objectives.

Jan 1, 2004