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By William D. Hanson

Celestine (celestite) (SrSO4), the primary ore mineral of strontium, is present in the DeQueen Limestone Member of the Trinity Group (Lower Cretaceous) in Sevier, Howard, and Pike Counties, southwest Arkansas. Two mappable celestine beds have been identified. One bed is commonly 3-5 in. thick, but ranges up to 18 in. in thickness; the other bed is generally 2-3 in. thick. The beds are concordant within the DeQueen Limestone and were formed by precipitation from periodically restricted sea water. Reports concerning celestine date back to 1929, when Hugh D. Miser and A. H. Purdue mapped the geology of the DeQueen and Caddo Gap quadrangles. A small amount of celestine was produced in the early 1940s in Howard County. During 1941, the J. W. Hintze Company collected 1,500 pounds of celestine for testing purposes. In 1942 and 1943,750 test holes were drilled by the Bennett-Clark Company in Howard County. Afterward, approximately 90 tons of celestine was open-pit mined and shipped to Texas for processing. Since then, no mining of celestine in Arkansas has taken place.

Jan 1, 1999

By Kenneth J. Miller

A novel two-stage froth flotation process to remove pyritic sulfur from fine- size coal is described. The process consists of a first-stage, standard coal flotation step in which high-ash refuse and some of the pyrite are removed as tailings. The first-stage clean coal froth concentrate is then repulped in fresh water, and a coal depressant, a pyrite collector, and a frother are added to float the remaining pyritic material. Laboratory and pilot plant flotation results with coals from the Lower Freeport and Pittsburgh beds are given. The pilot plant test results show that up to 80 percent pyritic sulfur reduction was achieved with the Lower Freeport bed coal and up to 50 percent with the Pittsburgh bed coal. Laboratory and pilot plant results were in excellent agreement, indicating that the process is a viable means of removing much of the sulfur from some coals.

Jan 1, 1974

By A. Yehia, J. S. Hu, J. D. Miller, M. Misra

Fluoride activation has been evaluated by Hallimond tube flotation of collophanite in terms of fluoride concentration, conditioning time, pH, and temperature. The results reveal that efficient oleate flotation of collophanite can be achieved by fluoride activation. Experimental results of fluoride adsorption by collophanite suggest that, at low fluoride concentration, a fluoroapatite-type compound may form on the collophanite surface by chemisorption of fluoride ions at calcium sites. At high fluoride concentration, calcium fluoride appears to form at the collophanite surface involving a surface precipitation phenomenon. The formation of CaF2 on the surface of fluoride-treated collophanite is further substantiated by the FTIR spectroscopic measurements, which suggest a metathetic exchange with phosphate from the collophanite lattice during the surface precipitation process.

Jan 1, 1988

By J. R. Allen

Environmental laws and regulations have proliferated over the last two decades. 1/ Within the last year, Congress has dramatically expanded the scope of the Superfund program 2/ and has enacted significant new amendments to the Clean Water Act.3/ In addition, EPA has shown no signs of slackening the pace at which it promulgates new regulations to implement statutory programs. The agency projects that over the next few years it will issue approximately 275 new regulations under the statutes it implements. 4/

Jan 1, 1988

By Lars Olaf Höglund

MiMi has been set up to be i) visionary, ii) strategic and iii) long-term. The planning as well as the executive phases involves industry, academia and authorities in close co-operation. MiMi focuses on improved, economically efficient management of mining waste, a challenge that requires combined and integrated research efforts across discipline boundaries. The MiMi programme is financed by the Swedish Foundation for Strategic Environmental Research (MISTRA) with support from the mining industry. The first programme phase covers the period 1997 - 2000, with intentions for additional phases. Planning, experience and results from the first programme period are highlighted. INTRODUCTION Most of the mining activities in Sweden takes place in the No

Jan 1, 2000

By R. B. Coleman, T. P. McNulty

HISTORICAL PERSPECTIVE Environmental protection is not a newcomer to the minerals industry, there having been numerous examples dating from decades ago. Sometimes the awareness of a need for preservation or restoration derived from the ethics and principles of the engineers and management responsible for development and operation of a property. On the other hand, pressures to clean up industrial messes frequently were applied by special interests such as farming and ranching, recreational and conservational groups, and local governing bodies. Mineral industry environmental controls in this century have therefore been a patchwork of good intentions and bad, clean operations and dirty ones. The Hoboken siphon converter for converting copper matte while effectively capturing sulfur dioxide at a relatively high concentration was developed in Olen, Belgium in 1928, a full sixty years ago. The alternative was closure of the Hoboken smelter by Belgian government health officials who had become intolerant of sulfur dioxide emissions which were causing serious respiratory ailments in the river valley in which Olen is situated. As early as 1958, the Anaconda Company had a full-time botanist on its metallurgical research staff with the responsibility of learning how to vegetate the extensive tailings deposits at Anaconda, Montana. By that time, considerable progress had already been made in restoration of Silver Bow Creek, which at one time was “dead” for as far as 40 miles down- stream from the point of entry of acid mine drainage in Butte.

Jan 1, 1989

By Van E. Housman, Stephen D. Hoffman

The Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA), also known as "Superfund", requires a listing of sites that have known releases or threatened releases of hazardous substances, pollutants, or contaminants throughout the U.S. When EPA determines that a significant threat exists, it places the worst contaminated sites on the National Priorities List (NPL). CERCLA provides EPA broad authority to clean up hazardous sites that threaten human health and the environment. There are currently 52 sites on the NPL that were placed on the list because of high human health or environmental risk as a result of non-coal mineral extraction, beneficiation, or processing operations. This list covers mining sectors from aluminum to zinc. While some of these sites were abandoned, many are still operating. (There are additional mine sites that have been recently proposed to be included on the NPL that are not included in this paper.) EPA is continuing to develop a mining program to address human health and environmental threats from active non-coal mines. EPA has performed a comprehensive study to assess the waste management practices at all of the 52 mine sites on the NPL. In addition, EPA is continuing to collect information on the specific mining sectors (i.e., gold, copper) that represent many of the NPL mine sites. One of the goals of this effort is to attempt to identify the types of mining practices that lead to human health and environmental problems at the NPL mine site. EPA estimates that there are currently 500 to 1,000 active mines (not including placer operations). While some mining NPL sites began operations before the turn of the century, only a handful of the NPL mines entirely ceased operations prior to 1970. Of the 52 NPL sites studied by EPA, 12 are currently active. By definition, these mines represent current mining practices. Approximately 17 additional NPL mines that ceased operations between 1970 and 1990 represent some degree of current mining practices. Therefore, at best, less than half on the 52 NPL mine sites can be said to definitely represent past mining practices. Although some mining waste management practices have changed over time, the basic technology for extraction and beneficiation of mineral ores have remained fairly constant over the last fifty years. While the use of acid to leach copper dumps, the use of cyanide to leach gold in heaps, and the spread of solvent extraction techniques has changed some aspects of mining, the basic operation of removing ore from the ground and concentrating it through beneficiation has remained fundamentally the same as when most of the non-active

Jan 1, 1992

By Dale A. Shay, Roy R. Cellan

The Santa Fe Mine, located in west central Nevada, began leaching ore in 1988 and completed ore processing in 1995. Homestake Mining Company has completed final reclamation of the site, including remediation of bare surface soils resulting from the oxidation of sulfide minerals and migration of acidity in the mine waste repositories. The need to remediate oxidized sulfides and mitigate resultant acidity at the Santa Fe Mine emphasizes the economic, reclamation, and environmental advantages for understanding and pre-planning for management of potential sulfide wastes during mine planning phases. The lack of pre-planning by mining companies for sulfide waste management was common in the 1980's due primarily to mining of reserves characterized largely as oxide deposits and to the common opinion that low moisture regimes in arid or semi- arid climates would not allow for significant acid generation. Since the 1980's, operational experience has shown that sulfide wastes, deposited randomly in waste dumps and without adequate planning for final reclamation success, can create final reclamation problems that are very costly to remediate. While mine waste characterization, waste management plan compilation, and in-pit selective waste handling procedures add operational costs, the reclamation experiences at the Santa Fe Mine are indicative that pre-planning and management is worthwhile both in actual overall cost efficiency and in successful reclamation of the mine site. The reclamation program at the Santa Fe Mine shows Homestake's continued commitment to the successful management and reclamation of their mine sites.

Jan 1, 2000

By C. J. Weiss

"A commercially available Through-the-Earth (TTE) communications system was evaluated at an underground coal mine in eastern Kentucky. This field study was conducted as part of a larger multi-site evaluation of available TTE systems to determine their operational sensitivity. Field testing is being performed along with simulation techniques developed for geophysical surveys. The results of the field test will additionally be used to determine the applicability of these simulation techniques to TTE communications. The mine detailed in this paper was idled at the time of the study, which provided the nearest practical representation of a post-event mine shutdown. For this study, the three following communication modes were tested: surface-to-underground, underground-to-surface and surface-to-surface. Standard deployments of the TTE system using the manufacturer’s recommended procedures were able to achieve clear communications between underground and surface locations. Other arrangements of the units yielded intriguing results, some of which were predicted by computer simulations, others were unexpected. Future experimentation is planned to further evaluate the observed phenomena. INTRODUCTION The ability to establish effective communication between surface and underground personnel after a mine event is essential for both mine evacuation and mine rescue efforts. Current communication technology is reliant on physical infrastructure, such as antennas, cables, and repeaters, located throughout the mine. Such systems are easily disabled during a mine event because of their vulnerability to physical damage. A true emergency communications system would have the ability to function regardless of a mine’s physical state. Through-the-Earth (TTE) wireless communications technology has the potential to provide such a tool. Wireless TTE communications are exceptionally challenging because electromagnetic (EM), or radio, signals are subject to drastic attenuation as they travel through solid strata. In addition to attenuation, EM wave propagation is directly affected by the physical and petrographic characteristics, mineral compositions, metamorphic properties, and the degree of water infiltrations in the strata [1-5]. These strata characteristics are unique to each mine thus making the design of an effective, universally deployable, and reliable TTE communications system very difficult. At present, TTE technology is in the preliminary stages of practical deployment with only a few permissible TTE systems commercially available."

Jan 1, 2015

By R. A. Haney

The Mine Safety and Health Administration (MSHA) has conducted studies both in coal and noncoal mines to evaluate methods for sampling and separating diesel particulates from mineral dust aerosols. The agency is investigating size separation techniques to distinguish between diesel particulate and respirable coal mine dust. Additionally, ashing techniques have been used to distinguish diesel particulate from mineral dust in metal and nonmetal mines. As part of these studies, personal exposures to diesel particulate for various mining occupations have been measured. This paper describes the measurement techniques and summarizes the exposure levels for various underground mining operations.

Jan 1, 1990

By Young C. Kim

Because of the tremendous technological advances achieved in recent years in microcomputers, it is not only technically feasible but also economically viable to develop an automatic truck dispatching system using a microcomputer. Such an effort was initiated by the Department of mining and Geological Engineering, University of Arizona in the summer of 1983. Up to date results and experiences prove that today's microcomputers can be economically employed for such a system to be used at small to medium scale open-pit mines. An IBM/XT microcomputer with 10 MB harddisk storage, together with automatic sensing capability of truck movements at several key locations in the pit, formed the core of this system. System software is written primarily in MICROSOFT FORTRAN with supporting subroutines in MACRO assembly language. The software is designed to automatically monitor truck movement throughout the pit, to make heuristic assignments based on expected shovel availability and truck travel times, and to record production statistics. It is currently dimensioned to handle 50 trucks, 10 shovels, 10 dump sites and 3 material types. Due to the lack of funds to purchase the necessary communications hardware, the work related to the automatic sensing of truck movements has not been performed to date. Otherwise, the automatic truck dispatching-system is fully operational on a realtime mode.

Jan 1, 1984

By John Ward Smith

Dawsonite bearing oil shale of Colorado's Green River Formation offers a unique and vast (6.5 billion tons of Al2O3) resource of easily extractable alumina. The processing methods required by the thermal reactions dawsonite and its oil shale carrier also require production of shale oil, soda ash, and nahcolite as marketable coproducts. These production methods are presented. The alumina production process is contrasted with the Bayer process to describe technical advantages of extraction of alumina from oil shale which may offset the problems associated with processing a relatively lean ore. While alumina production from oil shale requires development of new technology, the technical problems appear solvable. Only the political problems arising from the now onerous and completely unnecessary Federal oil-shale withdrawal appear less solvable.

Jan 1, 1980

By Gordon T. Clark, Stephen H. Gleaton

This paper discusses the conceptual design of cut-and-cover tunnels currently being considered as one of the replacement options for the earthquake damaged, elevated double-deck highway and seawall built in downtown Seattle 50 years ago. The 4.8 km (3 mile) long, 6-lane improvement consists of 1.6 km (1 mile) of at-grade roadway with aerial interchanges, 1.6 km (1 mile) of large two-level cut-and-cover tunnels along the Elliott Bay waterfront, and retrofit of the 50-year old, 1.6 km (1 mile)long Battery Street tunnel and north transition to grade. Construction of deep cut-and-cover tunnels, in complex glacial geology overlain by hydraulically placed fill immediately adjacent the existing sea wall, will require extensive use of concrete diaphragm walls, ground improvement and dewatering. The potential liquefaction and lateral spreading of the fill materials in this active seismic region pose significant design challenges and risk.

Jan 1, 2003

By S. Zaman, F. F. Aplan, Franklin T. Davis

This section deals with the oxides of heavy metals, namely, columbium and tantalum, rare earths, chrome, manganese, titanium, tin, and tungsten. Table I contains the production figures for each of these commodities in the US and in the world in 1977. Specifications for concentrates are also summarized as well as prices for concentrates in 1977. In each chapter an attempt has been made to describe the more common commercial mineral involved with the commodity and the processes used to recover and concentrate the minerals, as well as geographical areas where these processes are utilized.

Jan 1, 1985

By S. M. Hossaini, M. Ataei, H. Moosavi

The abstract highlights the importance of pillar stability in underground coal mines and the influence of rock mass strength and joint orientation on pillar behavior. The study employs numerical modeling using the distinct element code (UDEC) to investigate the impact of these factors on pillar stability. The research considers different joint orientations and varying rock mass strengths, analyzing parameters like stress distribution, displacement, and failure patterns. The findings reveal that both joint orientation and rock mass strength significantly affect pillar stability, with specific combinations leading to reduced safety factors and increased deformation. The study concludes by emphasizing the importance of considering these factors in pillar design for safe and efficient mining operations.

Apr 4, 2022

By M. Raffaldi, J. Johnson, M. Stepan, D. Benton

"The Office of Mine Safety and Health Research (OMSHR), Spokane Mining Research Division (SMRD), is continuing its High-Energy High-Displacement (HEHD) testing of field-scale shotcrete panels. A test program was developed to determine the relationship between applied force, displacement, and energy for both unreinforced and reinforced shotcrete panels. Reinforcement options consisted of synthetic macro-fibers, sprayed polyurea liners, chain-link fence, welded-wire mesh, and combinations of these products. During testing, photogrammetry was used to measure the geometric changes of the panels, including volume changes and panel cracking. These measurements were correlated with the load and displacement data, allowing visual observation to be related to the applied force and displacement. The test results provide a comparison of the mechanical performance of the various panel types and can be used by the practicing engineer to evaluate installed support based on visual observation of cracking and deformation. Visual assessment of the loading cycle and strength capacity of shotcrete in underground excavations will improve mine safety by providing a means to quantify the stability of installed shotcrete support. INTRODUCTION The National Institute for Occupational Safety and Health (NIOSH), Office of Mine Safety and Health Research (OMSHR), Spokane Mining Research Division (SMRD) is continuing research on the behavior of shotcrete when used as the surface support component in mining ground support systems. Ground control safety often depends on supporting, or at least containing, the ground between the rockbolts. Shotcrete and mesh, in various combinations and with other components, are often used to accomplish this (see Figure 1). Maintaining support pressure during ground deformation is key to the performance of these systems, and to ensuring miner safety. However, the toughness of a ground support system–the ability to maintain strength over large deformations–is difficult to quantify. Researchers at SMRD have responded to this deficiency by designing a full-scale test device, described previously by Martin et al. [2015a], and beginning a testing program to assess the behavior of shotcrete surface support reinforced with a variety of products including: fibers, chain-link mesh, welded-wire mesh, spray-on polyurea liners, and combinations of these products. This paper presents the findings of these tests."

Jan 1, 2016

By Eileen Ashworth

Computer-assisted instruct ion is now being used in areas as diversified as training handicapped children to preflight simulation for airline pilots. This paper reports on two courses that have been developed at SDSM&T on the PLATO system for miner safety training. Advantages of computer-assisted instruct ion for this type of training is discussed. (Figures show examples of actual use.) A discussion will be given on other applications such as maintenance troubleshooting, training of engineers and managers at remote sites and training of local people for working in the mine.

Jan 1, 1983

By N. T. Rempe

The underground voids that result from mining provide opportunities for deep geologic waste disposal (DGWD). Such disposal could solve many environmental problems. DGWD takes careful planning, technology transfer and true partnership between waste generators and mine/repository operators. The US government is now planning on using specially mined excavations to dispose of radiotoxic and mixed waste. Using the experience gained from the domestic projects that are now in preparation and from foreign repositories that are now in operation, US mines can claim their rightful share of the growing market for DGWD.

Jan 1, 1997

By P. Coleman, J. C. Kerkering, S. Iverson

Fault tree analysis is a systematic safety analysis tool that proceeds deductively from the occurrence of an undesired event (accident) to the identification of the root causes of that event. One recurring mine safety problem-a dozer falling into a void over a drawpoint on a coal surge pile-was analyzed using available, inexpensive fault tree programs on a personal computer. The analysis identified basic and intermediate events that led to the burial of the dozer and graphically depicted the interrelationship between these various subordinate events as well as the various chain of events leading up to the primary event. A sensitivity analysis on these probabilities showed which events had the greatest influence on dozer burial in a coal surge pile.

Jan 1, 2001

By Thomas D. Kaufmann

The 1982 recession set the US mining and metals industries reeling. Will the oncoming recession of 1991 hit as hard? Probably not, thanks to a shallower downturn, a weaker dollar and remarkable lower costs. Effects of the last recession That the 1982 recession was traumatic to the American mining and metals industry is an understatement. Quantities of metals consumed dropped. Metals prices fell despite continuing general inflation. The resulting real gross revenues of producers of each of the major metals plunged, in the trough of 1982, to levels one-fourth to two-thirds of those of the peak of 1979 (Table 1). By contrast, most industries in the United States were not hit anywhere nearly as hard. Real GNP, the aggregate of all production, slipped only 1 % from 1979 to 1982. Metals are most sensitive to the business cycle because of their applications. All metals but gold are raw materials to downstream industries. Raw materials are victims of strong fluctuations. This is because buying industries try to hold high inventories in boom periods when goods are in short supply. They reduce inventory levels in buyers markets when suppliers have idle capacity and raw materials are in ample supply.

Jan 1, 1990