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By Jonathan K. Hrica, CASSANDRA L. HOEBBEL, Jennica L. Bellanca

Accidents involving powered haulage and mobile equipment like haul trucks are a major safety concern in the U.S. mining industry. They account for more than 50 percent of surface mine fatalities each year [1]. A recent National Institute for Occupational Safety and Health (NIOSH) analysis of 91 fatal incidents identified loss of vehicle control and situational awareness as key contributors [2]. However, the first-hand perspectives of operators are often missing, emphasizing the need for deeper insights into operators’ decisionmaking, lessons learned, sensory cues and mental strategies used during near-miss events. The findings in this analysis will help inform the development of training and safety solutions to prevent or reduce haul truck accidents.

May 1, 2025

By J. P. Sieverson

The Comprehensive Environmental Response, compensation, and Liability Act (CERCLA -commonly referred to as Superfund) was passed into law in December 1980 in the wake of such incidents as Love Canal and the Valley of the Drums. Superfund was originally perceived as a way of cleaning up spills of hazardous substances and/or cleaning up abandoned hazardous waste dumpsites. In February 1981, Michael Cook, EPA deputy assistant administrator for hazardous emergency response, called Superfund "a tremendously powerful law. It could revolutionize the way the environment is protected, but we certainly don't intend to realize the full potential of the law for some time." These words have proven prophetic for Asarco's East Helena Smelter.

Jan 1, 1988

By Richard J. Frechette

Very few facilities containing hydraulically deposited tailings have been completely reclaimed and capped at this time. Design of a closure cap for a tailings impoundment has relied heavily on consolidation theory in order to achieve a cap that maintains sur­face drainage. Obtaining data for the consolidation evaluation can be difficult and costly. The author reviews the performance of two tailings impoundment closure caps that have been suc­cessfully installed and presents the experience gained from these projects with an emphasis on the ability to optimize cap design through post-operational monitoring prior to initiating cap con­struction. Using the optimization approach, a significant earth­work quantities reduction may be realized for the ultimate cap.

Jan 1, 1998

By P. Gelfi, G. Hill, A. Showell, V. Martins, R. Dunne, R. Jenkins

Carbon attrition losses are not usually a prime consideration for CIP equipment selection and CIP plant design. However, the costs as a result of carbon attrition and associated gold lost with carbon can be high. Recorded carbon losses for Newcrest operating gold plants were shown to vary widely from plant to plant. The Tuckabiana plant recorded an overall loss of only 0.3g carbon /t ore which is very low by industry standards. A comparative carbon management study was undertaken by Newcrest to highlight the reasons for the excellent record of Tuckabiana operation compared to other Newcrest plants. This paper discusses the results of the comparative study and high­lights areas of concern with respect to carbon attrition.

Jan 1, 1995

By Syd S. Peng

Popular concepts of resin and conventional roof bolting The conventional roof bolt with shell anchor was first introduced for coal mine entry support in the late 1940s. The general concept of a reinforcement mechanism for this type of bolt is suspension. This means the shell anchor must be anchored well inside a competent rock stratum (such as sandstone, limestone or firm shale) so the bolt suspends the underlying weaker strata. This concept has and will continue to dominate the use of conventional roof bolts. Under this concept, the conventional roof bolt is not suitable for the stratigraphic sequences in which a strong, firm stratum is not available within the economic anchorage horizons.

Jan 1, 1994

By Jay A. Bowden

In April of 1990, Homestake Mining Company began a 5,100 m (16,700 ft.) exploration drift from the Homestake Mine in Lead, South Dakota. The drift starts from the mine's 6800 level, nearly 2,100 m below the surface, and extends north to further explore occurrences of gold discovered by surface drilling. Access to the North Drift for men and materials and for disposal of waste rock is limited to the Homestake Mine's #6 Winze, which serves as the major production shaft for the deep levels of the mine. This paper will discuss the successes and challenges encountered while managing a tunneling project 2,100 m below the surface and from an active mine.

Jan 1, 1993

By R. K. Mehta, U. Cetin

The Nevada Test Site is located approximately 100 km (65 miles) northwest of Las Vegas, NV. The site was primarily used by the Department of Energy for the field testing of nuclear weapons and has been contaminated by several million cubic feet of low-level radioactive wastes, heavy metals, explosive materials, and volatile and nonvolatile organics. The transportation and leaching of these contaminants are creating serious environmental problems. The purpose of this study is to examine pozzolan, a natural alumina-silicate mineral, as a possible replacement for the existing impermeable clay barriers. In the first phase of this study, radionuclide sorption characteristics of pozzolan were investigated. This paper presents the results of the adsorption tests for the target radionuclides.

Jan 1, 2000

By R. L. Grayson, L. L. Probert

A three-year project focusing on the depth profiling of respirable coal mine dust particles using scanning electron microscopy coupled with energy dispersive X-ray analysis resulted in the development of statistically classified particle-behavior models. The models depict the changing silicon fraction for particles at 5-, 7-, 9-, and 11-keV accelerating voltages, thereby giving a clear indication of the nature of various types of mineral particles. This paper focuses on the results for respirable quartz particles sampled from five underground coal mines across the US. Through statistical analysis of results the relationship between the fraction of surface available quartz in respirable dust samples and coal rank is established for three Pennsylvania coal seams.

Jan 1, 1995

By James M. Prudden, Jon C. Sprague

Valdez Creek Mining Co. properties consist of multiple intersecting paleo-placer channels containing appreciable quantities of coarse gold. Reverse circulation drilling, combined with geophysics, is used for both exploration and development reserve determination. Classical drill-blast-load-haul open pit mining techniques used for the 22,000 cubic yard per day production schedule required modification to compensate for arctic winter operating conditions. High wall stability problems within the glacial sediment overburden necessitated developing multiple dewatering methods and variable pit slope designs to eliminate unstable pit wall conditions. Processing mine run fluvial gravels utilized a classical winter protected screening plant-sluice box recovery system enjoying high metallurgical recoveries and zero discharge tailings disposal.

Jan 1, 1987

By W. R. Bush

Radiation protection in uranium mines and nuclear reactors is compared, with the objective of determining if any radiation protection practices which have worked well in one area can be adapted to the other area, especially from reactors to mines since radiation protection is more highly developed in reactors. Several areas are identified where improvements can be made in radiation protection in mines, the most important being improvement in ventilation at the workplace, greater attention to special monitoring during upset conditions, and a need for a substantial increase in radiation protection staff. It is concluded that, although considerable room exists for improvement, the general approach to radiation protection presently being followed seems appropriate for the circumstances encountered in mining.

Jan 1, 1981

By C. C. Clark, S. J. Jung

Determining the correct combination of mix components and water for high-density paste backfills that have the transport and deposition properties necessary for a mining operation is a difficult task. Rheologic properties cannot be determined without conducting full-scale pumping tests, and data from existing tests tire very limited. This paper presents the findings of investigations undertaken to determine if paste-backfill rheology can be determined using existing techniques and to determine which mix and system variables have the greatest influence on transport-pressure loss. Data from laboratory-scale pumping tests were used to produce a rheologic model of flow behavior for comparison, and a statistical analysis was conducted to determine the most significant factors affecting transport-pressure loss.

Jan 1, 1996

By Bruce B. Redpath

Single-charge cratering tests can provide a direct measure of the powder factor necessary for achieving a desired effect in conventional blasting. If a desired blast effect, such as fragmentation or mound velocity, is produced by a single point-charge at a particular scaled depth of burial, then the cube of the reciprocal of that scaled depth is the appropriate powder factor for duplicating the effect in a conventional array of blast holes. Scaling formulas are presented that provide a link between point-, line- and plane-charge geometries, and which can be Apparent crater used for blast design. Mound and burden velocities from several sources are compared and several examples of blast design are given.

Jan 1, 1977

By Jay Jones, William D. Rech

The Henderson Mine developed a water treatment system in 1985 to meet the NPDES requirements for its mine water discharge. Unacceptable levels of Zinc and Manganese formed the basis for the design and operation of the treatment system. Since initial start up, this system has reliably removed metals from the mine water and facilitated low cost compliance with water standards. The potential addition of a bio- monitoring requirement to the NPDES Permit in 1990 has added a second dimension to the metals removal process. This paper will review the history of Henderson's success at developing a low capital treatment system for metals removal and the anticipated effects of bio-monitoring upon this system based upon preliminary bio-monitoring screening.

Jan 1, 1991

By Simon D. Handelsman

Technical co-operation activities of the Department of Technical Co-operation for Development of the United Nations Secretariat have included the introduction of electronic data processing techniques in mineral sector projects for several years; computers have been provided to countries in Africa, Asia and Latin America. Advisory services are provided to interested developing countries at their request concerning applications for various uses in mineral sector activities. They include advice on appropriate hardware and software depending upon the requirements of the particular Government. The Department's activities in this area are described. The input from a Group of Experts on this subject convened by the United Nations, and their conclusions and recommendations, are also discussed.

Jan 1, 1986

By W. Dalmijn, H. de Ruiter

"The decline in students for mining and metallurgical engineering in the last few years has lead to the closure of many university departments in all first world countries around the world. Three independent studies carried out in Europe, Australia and North America indicate that during the next decade the demand for mining, minerals processing and metallurgical engineers will be significantly higher than the supply. Demand for engineers will increase even more because many of the professionals in industry are about to retire within the next 5 years. Meanwhile mining is a growth industry, minerals demand continues to increase in line with the growth in World GDP, as illustrated in the Graph at the end of the paper."

Jan 1, 2005

By Eric K. Albert

The permit generation and review process represents both a time consuming and expensive task for industry and government alike. Changes in regulations and in review procedures cause additional delays. This leads to potentially higher costs of doing business and the extension of time for a project to lie started. This paper describes the motivation and methodology of applying an expert system to function in the role of a permit reviewer. The problems of representing the knowledge of the reviewer and regulatory criteria are illustrated. Futhermore, the selection method for the expert system shell is addressed. Finally, a sample review is demonstrated to show the results of applying this artificial intelligence method to the process of permit review.

Jan 1, 1989

By Kenneth S. Graham, S. C. Gambrell

A short term, simple roof bolt load cell which uses a birefringent (photoelastic) coating as its sensing element has been developed. The load cell is installed between the bearing plate and the nut/washer and measures the initial force after installation by the bolting machine. The load cell can be removed from the bolt and used again to measure initial force in another bolt if desired. Because temperature and humidity changes in the mine cause creep/relaxation of the coating and/or adhesive, the load cell is useful for accurately measuring force for a period of only two weeks after installation. Force in the bolt is determined by referring to a calibration curve for the load cell.

Jan 1, 1992

By Raphael Mourad, Colin R. Phillips

Investigation of the traps in LiF:Mg, a multi-peak phosphor, was carried out using simple phosphorescence decay analysis. Half lives at room temperature of the trapping centres (peaks -lb, -la, -1, 0, 1, 2, 3a and 3) in the phosphor after irradiation with [a] radiation were found to be 3 s, 5 s, 28 s, 4 min, 15 min, 1 h, 6 h and 2 d respectively. Justification for the method of analysis is pro- vided and the results of measurements compared with published data. The effects of pre-annealing at 400°C for 1 h and 80°C for 24 h on the trapping configuration and on the trapping efficiencies were also studied.

Jan 1, 1981

By I. Dumitrescu

Since 1990, the entire Romanian mining industry has suffered a major restructuring, i.e. technical and economic. The large majority of the remaining active mines are these with a chance for economic comeback. This is also the case for the mines that belong to MINVEST Deva Company; most of the mines are closed, and are waiting to be reclaimed. The authors present the closing procedures of the former copper mining perimeters managed by MINVEST. It is well known that pollutants of concern for the environment must be monitored to obtain reliable information on the quality of ambient conditions and to minimize their impact on the environment. Consequently, the monitoring problems during the closing procedures will be presented.

Jan 1, 2008

By Barry K. Johnston, Norman W. Bainbridge, Neville C. Lockhart

CSIRO and its collaborators have developed a major R & D project on dewatering of coal. This involves sub-projects on (i) the fundamentals of coal-water associations; (ii) reducing the variability of product moisture levels from small coal centrifuges; (iii) process mechanisms and optimisation for fine coal dewatering; (iv) pilot scale testing, engineering development and innovation. Results from each of these sub-projects are presented, and the pilot facility incorporating a vacuum filter, belt press, membrane press, hyperbaric filters and centrifuges, is discussed. The vacuum filter and membrane press can be configured for electric-field assisted dewatering, which provides substantial enhancements in the rate and degree of dewatering for fine coal, coal tailings, and other suspensions.

Jan 1, 1995