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By Tim O’Neil

Dressed in black tie and Victorian attire, some 200 people came to Leadville, CO, for a September weekend featuring a National Mining Hall of Fame and Museum (NMHF&M) induction banquet and a scenic mountain train trip to Fremont Pass and the Climax Mine. The 18th annual induction banquet on Sept. 17 began with cocktails and a open house. It was a chance for visitors to tour the National Mining Museum including the new Hennebach Wing, opened in February. The new wing is named in honor of Ralph Hennebach, retired chairman of Asarco. Formerly Leadville Junior High School, the Hennebach Wing encompasses more than1,440 m2 (15,500 sq ft) of floor space in two stories. One prominent feature is a 1923 Wills Sainte Claire touring sedan. Climax Molybdenum donated this first all-molybdenum steel motorcar. Docents were available throughout the museum to give banquet attendees directions and answer questions.

Jan 1, 2005

By Steve J. Czehura

The Butte quartz monzonite is the host rock for early porphyry copper style mineralization and subsequent mesothermal-epithermal, enargite-gold style veining that transects the district. The east-west Anaconda system veins sustained mining for over a century. They include the Emma, Anaconda-Original, Syndicate, Badger-State and Alice-Rainbow veins, each with strike lengths of more than 3,660-m (12,000-ft) and vertical continuity in excess of 1,370-m (4,500-ft) with mining widths from 1.5- to 15-m (5- to 50-ft). These characteristics are unique to Butte. The incredible dimensions and tenor of these veins have yet to be surpassed and Butte is still touted as being the “Richest Hill on Earth.” The Anaconda Company was formed in 1895 to develop underground copper reserves in the district. It eventually consolidated all operations under one company. Production from underground mining continued through the mid-1970s. Openpit mining in the Berkeley pit began in 1955 with the extraction of supergene ores, along with the remnants of deeper horsetail zones inaccessible to the underground mines.

Jan 1, 2006

By Maurus Seet Hong Hua

Introduction Coal has always been China's predominant energy resource. The country ranks among the three richest countries in coal reserves in the world, next to the US and the Soviet Union. According to China's Ministry of Coal Industry (MCI), coal accounted for about 72% of the total national energy consumption. Despite efforts to increase the output of oil and hydropower, coal is predicted to remain dominant on the energy scene by increasing its share to 77% by the turn of the century. To match the rapid growth in the agricultural and industrial sectors, MCI has targeted the coal industry to double coal output from 600 Mt/a (660 million stpy) in 1981 to 1.2 Gt/a (1.3 billion stpy) by the year 2000. How is this goal to be achieved? According to MCI, it will be accomplished by: • building new underground and surface mines with a total output of 400 Mt/a (440 million stpy); • increasing the output of existing state-controlled mines from the present 344 Mt/a (368 million stpy) to 400 Mt/a (440 million stpy); and • developing and increasing the output of small, local mines run by province, county, and production brigade from the present 276 Mt/a (304 million stpy) to 400 Mt/a (440 million stpy). Building new underground and surface mines New underground coal mines will be developed in areas where the coal industry has already made headway and infrastructures currently exist. This is to optimize hardpressed capital spending on investment. Ten existing coal production bases were selected in nine different provinces that met these requirements. The underground mines scheduled to be constructed in stages at he existing coal production bases will have a total output of 200 Mt/a (220 million stpy) by the end of the century. Regarding surface mines, four mines in the Inner Mongolia Autonomous Region and one in Shanxi province have been earmarked for construction during the same period. By the year 2000, these surface mines are expected to produce 200 Mt/a (220 million stpy). Foreign equipment, machinery, and surface mine stripping technology were all involved in different degrees in the development of the five new surface mines. Some have signed joint venture agreements. Occidental Petroleum Corp. is in a joint venture with China in developing Ping-shou's 15 Mt/a (16.5 million stpy) Antaibao No. 1 open-pit. The Shentou power station, situated nearby, is anticipated to consume 3.2 Mt/a (3.5 million stpy) of the coal it produces. Some is designated for export. Increasing output There are 554 state-controlled mines that have been in operation since before 1980. They produce 344 Mt/a (379 million stpy). To increase capacity, MCI has laid out some guidelines. • Coal prospecting near existing mines must be given top priority and intensified so that workable reserves can be increased. This would lengthen the mines' useful life. • Many mines and slopes that were constructed during the 1950s are very small and densely populated. These small mines and slopes are generally very short along the strike. As a result, coal faces and levels require frequent

Jan 3, 1986

By C. A. Wiggins, J. M. Kennedy

The Benbrook Connection tunnel forms approximately 6,666 m (19,560 ft) of17,678 m (58,000 ft) of raw water pipeline connecting Lake Benbrook with the Rolling Hills Water Treatment Plant. This connection is designed to minimize costs to the owners, the Tarrant Regional Water District, for providing raw water to its’ various clients. The geological formations through which the tunnel passes and the design requirements resulted in some-what unique applications of initial ground support systems which were modified by the con-tractor to optimize the mining operations. The pipe sections, fabricated in 12 m (40 ft) sections, are concrete lined and coated steel pipe. Construction of the work shaft and tail tunnel was also modified to suit the contractors methods. A Lovat universal TBM was chosen to excavate through the various rock types. The pipe sections will be transported using beam carriers.

Jan 1, 1997

By Jim Merza

The recent heightening of environmental issues has forced more and more mining operations to focus on developing new methods to control dust problems encountered at their concentrate dryers, stock piles, tailings ponds and during the loading, transportation and unloading of their products. The development of dust control agents requires a quick reliable and most of all accurate method to evaluate the performance and to optimize the formulation of these products in the laboratory, thus avoiding expensive field trial evaluations. This paper gives an overview of the industry requirements for specialty dust control agents, application techniques and current laboratory evaluation procedures. The paper will also outline the development of a unique dust suppression testing apparatus called the "Dust Box, which is used to evaluate chemical dust suppressants at the laboratory level. Laboratory results from two test programs on different substrates are presented in the paper.

Jan 1, 1994

By Sigmund J. Sulinski

The following is a progress report on a continuing study being made by the Sanitary District for purposes of developing reliable data for predicting costs and progress on future tunnel contracts. All data available to date on five separate tunnel contracts has been analyzed. All were machine-mined in soft ground, all used steel ribs and wood lagging and finished inside diameters varying from 5'6" to 6'6". Basic data regarding progress per shift, hours mined per shift, hours of downtime per shift, cause of downtime and type of soil mined were reported by the District's resident engineer at the job site. Figure 1, Weekly Mining Report is an example of the form used. Data regarding manpower and equipment used during tunnelling operations was also supplied by the resident engineer during the course of construction. Soil type being mined was verified by the resident engineer during construction, by visual observation, and compared with data listed on a previously prepared soil profile. The soil profile is a graphic presentation of anticipated soil stratas superimposed on a cross section

Jan 1, 1997

By Fu Lizhu, Qiu Tingsheng

An application of water-system magnetizing technology for the mineral processing and hydrometallurgy is introduced in this paper. The water-system magnetizing technique flotation and cyanidation leaching test of vein-ore of gold-bearing and conventional technique flotation and cyanidation leaching of gold-bearing vein-ore was carried out. The best condition of water-system magnetizing was determined by orthogonal test. The results have shown that the water-system magnetizing technology may increase the efficiency of flotation and cyanidation leaching for gold. The industry-scale test results also show that it can increase flotation recovery by 1-3% and leaching extraction by 3-5% of a gold-bearing vein- ore. The interaction of magnetizing water-system with minerals was carried out and initially investigated.

Jan 1, 1995

By Jeffrey C. Reid

Computer processing and high resolution graphics display of geochemical data were used to quickly, accurately, and efficiently obtain impor¬tant decision-making information for tin (cassiterite) exploration, Seward Peninsula, Alaska (USA). Primary geochemical dispersion patterns were determined for tin-bearing intrusive granite phases of Late Cretaceous age with exploration bedrock lithogeochemistry at the Kougarok tin prospect. Expensive diamond drilling footage was required to reach exploration objectives. Recogni¬tion of element distribution and dispersion patterns was useful in subsurface interpretation and correla¬tion, and to aid location of other holes. Tin was its own best pathfinder. Arsenic, also a useful pathfinder element, forms a discrete halo peripheral to tin mineralization. The arsenic halo is expressed in hand specimens by asenopyrite and/or scorodite staining.

Jan 1, 1989

By M. Li, J. D. Miller

It has been discovered that water insoluble alcoholic solutions of alkyl hydroxamic acids serve as selective collectors for the flotation of phosphate mineral resources (Miller et al., 2000). The effectiveness of the new collector chemistry has been demonstrated by the results from single stage bench scale flotation experiments for feed material from plants in Florida, North Carolina, and Utah. In the best case, from experiments with low grade (5% P20,) coarse feed (16 x 35 mesh), a single stage phosphate recovery of 95% was achieved with a concentrate grade of 31% P20,. Such a separation efficiency could not be achieved using the traditional fatty acid/fuel oil collectors as is evident from a comparison of the respective grade/recovery curves.

Jan 1, 2002

By R. L. Grayson, J. R. Warneke

The mining industry has searched for a message that will resonate with the public while focusing on the industry’s positive contributions to society. Thus far environmental groups remain unconvinced, and the public is still largely uninformed. In the authors’ opinion, a number of recent events and experiences have converged to help shape a more effective public communication on mining’s important role. This paper presents a fresh and cogent perspective on coal’s role in sustaining society by anchoring the message in a transparent material flow analysis that links coal’s impacts across a broad range of social and environmental aspects.

Jan 1, 2006

The 20th annual American Mining Hall of Fame Awards Banquet sponsored by the Mining Foundation of the Southwest will be held at the Westin La Paloma in Tucson, AZ, on Saturday, Dec. 7, 2002. This year’s inductee, guest of honor and featured speaker is J. David Lowell, one of the preeminent exploration geologists of the past 30 years. Among his most recent discoveries is the world-class Pierina gold deposit in Peru, currently owned and operated by Barrick Gold. As representatives of mining heritage, the Hall of Fame will induct Howard Allen Twitty, Sr., and Bernhardt Rohe. Twitty was a respected public lands attorney. He made significant contributions to the mining industry by representing several major companies in many court cases. He was also the author of numerous papers on mining law. Rohe was managing director of Peñoles. In that position, he helped guide the Mexican mining company for its growth into the international mining company that it is today.

Jan 1, 2002

By G. Brackebusch, S. J. Jung

Backfilling techniques are widely used in large-scale underground mines. Massive pillars, which have been left in place for stability, limit mining activity. Backfilling allows safe recovery of the ore remaining in pillars and assures long term stability. In deep mines expected high stress can be relieved with the backfill. Initially, waste rock was used to fill the openings with mixed results. The need to improve safety and reduce costs has prompted the industry to investigate alternatives. Hydraulic filling with Portland cement added has shown considerable promise, but little has been done to define the parameters of design effective system. The purpose of this study is to determine the relationship between backfill and mining components that can be used to effectively design a best-case hydraulic backfill.

Jan 1, 2000

The 18th annual American Mining Hall of Fame Awards Banquet sponsored by the Mining Foundation of the Southwest will be held on Saturday, Dec. 2, 2000 at The Westin La Paloma in Tucson, AZ. The 2000 inductee, guest of honor and featured speaker at the banquet will be Ronald C. Cambre, chairman and chief executive officer of Newmont Mining. He will be honored for his role in positioning Newmont as an innovative and key player in the gold mining industry.

Jan 1, 2000

This research contributes to BioMinE (http://biomine.brgm.fr), an integrated European Union project of the Sixth Framework Programme. The general objective of BioMinE is the development and integration of innovative, environmentally friendly, biohydrometallurgical processes for the recovery of metals from primary and secondary resources within Europe. The work presented in this paper deals with the initial plan of study on the sustainable use of solid wastes derived from bio-processing of European metal bearing resources. The approach involves solidifying the waste into cementitious waste composites analogous to controlled low-strength materials (CLSM). The aim is to achieve composites of adequate mechanical, physicochemical and environmental integrity, thus providing a sustainable solution for dealing with such bulk products which are conventionally unmarketable and therefore normally discarded to landfill. Assessment has been based on largely ?model? wastes anticipated to be similar to bio-processing wastes. These include an ochreous mine water sludge and an industrial goethite residue. The work indicates that wastes containing high iron and calcium contents, typical of products from bioleaching of concentrates, could be beneficially reformed as CLSM of appropriate compressive strength. Due to the high water contents of these composites, porosity and hydraulic conductivity were correspondingly high. Flow-through leach tests showed some resistance to immobilisation of toxic elements. Work is continuing to reduce the risk of toxic elements leaching under environmental conditions. This will include laboratory-scale encapsulated systems of CLSM, designed and tested to produce a novel type of engineered fill structure.

Jan 1, 2006

By J. W. Mahar, E. J. Cording, F. L. Gau

INTRODUCTION The Washington, D.C. rapid transit system (METRO) when completed will consist of 98 miles of double track rail. Fifteen miles will be tunneled in rock and 12 large underground rock chambers will be constructed at station locations. The University of Illinois is under contract to Metro to provide observations and instrumentation services in the initial phase of construction. The work is coordinated through DeLeuw, Cather & Co., the General Engineering Consultant to Metro. The program is designed to monitor construction conditions as well as to provide information useful for the design of future rock tunnels and rock chambers in the Metro system. This paper presents the results of observations in the rock tunnels constructed to date. Most of the observations are in a 5000-ft-long, 30-ft-wide, double track tunnel in downtown Washington, D.C. Observations were also made in single track tunnels, shafts, enlargement areas, and pilot tunnels, and are being made in a large rock chamber 700 ft long, 76 ft wide, and constructed at shallow depth in a schistose gneiss. One of the major objectives of the observational program was to determine the orientation and character of joints and shear zones and to evaluate their effect on support requirements for various tunnel orientations and configurations. The consistency of geologic features throughout the Washington area has made the results of the initial study applicable to evaluation of support requirements on future tunnel contracts. The first section of this paper summarizes the geologic conditions in the tunnel and their effect on overbreak and rock movement.

Jan 1, 1997

By A. A. Mular

Examining a typical curriculum for mineral process engineers shows that traditional subjects remain important, namely, engineering, earth and basic sciences, mathematics and mineral proc¬essing technology. However, Table I shows additional subjects that may be woven into a modern curriculum, because of micro- and macro-engineering advances over the years. The ways to incorporate these subjects into the curriculum will vary from school to school. Such changes are in response to evolutionary technological and political needs as determined by society and business. Beginning with the 1950s, engineering empiricism was strengthened through micro-engineering, where fundamentals and mechanism serve as foundations. Scientific apparatus unique to the basic sciences (Zeta meter, FTIR spectroscope) was adapted to test new hypotheses. Coincidentally, as computers became more available, complex differential

Jan 1, 1992

By John A. Lombardi

The solutions used in the heap biooxidative treatment of sulfidic refractory Au ores and concentrates generally load free mineral acid and metals and, in time, become bacteria activity inhibiting due to increased acid and/or metals concentrations. The metals­acid loaded, bacteria action inhibiting, solution must then be: (a) processed, prior to re-use, to reduce its metals and/or free acid mineral acid components to bacteria activity compatible levels; or (b) neutralized prior to discharge. The most common solution processing method to adjust acid-metals contents is liming to effect the precipitation of dissolved metals and neutralization of acid sufficient for solution discharge or re-use. The lime treated solution is high in suspended, colloidal precipitates and requires clarification before reuse. Most often the "bleedstream" of biooxidation solution that is lime treated is discharged and req­uisite volumes of fresh water added to the process inventory. Depending on the level of bacterial action in a heap and the acid consumption characteristics of the ore/concentrate being biooxi­dized, the bleedstream taken from the circulating, irrigation on­off, solution, can be large (e.g., 10%-20% and sometimes as much as 50% of the daily solution flow requires treatment-dis­charge). The lime charge for bleedstream treatment is commen­surately large and represents a major operating cost of the bioox­idation process. The patented HW Process Technologies (HWPT) Engineered Membrane Separation (EMS™) method is an alternative biooxi­dation bleedstream treatment method. EMS™ processing removes the multivalent base metals ions in an acid solution to a small volume EMS™ "concentrate" (typically 25% of the feed­stream volume). The EMS™ method coincidentally makes a "clean acid" EMS™ "permeate" (typically 75% of the feed­stream volume). In general, EMSTM processing enables 75% of the bleedstream volume to be recycled; allows up to 2/3 of the bleedstream acid to be recovered as a 10% solution; and delivers dissolved metals in a highly concentrated stream suited to a. metals recovery or b. reduced cost lime neutralization for a given metals precip­itation relative to full bleedstream neutralization (typically a 30% lime use savings). Implicit in the recovery of process water for re-use and reduced reagent addition requirement for metals precipitation is a significant reduction in wastewater-sludge dis­posal facility size.

Jan 1, 1998

By D. Loring, J. Almgren

Climax Molybdenum Company’s Henderson Mine is a large panel caving molybdenum mine located about 43 miles west of Denver, Colorado. Three Joy M120-72-880 fans are installed in parallel on the No. 1 exhaust shaft. Throughout the mine’s history, ventilation changes such as the completion of the No. 5 exhaust shaft have decreased the utilization of these fans. To optimize fan performance they have been run with the full complement of 16 blades, down to as few as four blades. Since the completion of ventilation upgrades associated with the Henderson 2000 project, one surface fan has been operated under normal conditions with 10 or 12 blades. With the completion of a new network model of the Henderson ventilation system, a tool was built to develop fan curves for possible future fan configurations and predict future fan performance. This paper describes the tool and its use at Henderson.

Jan 1, 2007

By Albert W. Evans

Introduction Engineering Health and Safety is concerned with the understanding of the complex interplay between the risk of injury with technological ,environmental, individual, organisational and legal factors. With this understanding, the design and decision making processes can be balanced with the other objectives of industry and employment to arrive at solutions which place appropriate controls on technology and other aspects of human activities to prevent disease and injury to personnel in the coal mining industry and the design of safe production machinery and ancillary equipment. Advances in the detection and diagnosis of causes of diseases and the need for engineering health and safety in the coal mining industry has increased the need for appropriate education and training. Hazards arise in many forms; exposure to toxic chemicals, escape of radio - active materials, explosion of pressure vessels, contact with moving machinery, exposure to dust, environmental dangers such as excessive noise, high temperatures and manual handling etc. As technology advances, these dangers become more complex and less clearly defined and less easily perceived. Consequently, the ways of controlling the dangers also become more complex and wide ranging. The need to educate and train people in coal mining applications of engineering health and safety has been enhanced over the last five years and courses should be established to fulfil the need for competent people to deal with the problems which modern coal mining technology creates together with the legislation that governs engineering health and safety and to carry out research and development work in the coal mining industry. Industrial Involvement The engineering health and safety experts must be prepared to take a more active part in monitoring conditions that exist in the mining industry, and not design from information obtained from the mechanical, electrical and hydraulic expertise and off-the-shelf components from other industries. Surveying and control of the operating environment must be essentially the concern of the engineering health and safety experts and, whilst it is not possible to create a perfect environment for each machine, every effort must be made to minimise failures and hence plan for designs which will maximise

Jan 1, 1986

By Tim O’Neil

The US Bureau of Mines and the Santa Cruz Joint Venture (SCJV) are working on a production-scale, in situ copper recovery project in Arizona. The research is being conducted at the Santa Cruz site, located 11.2 km (7 miles) west of Casa Grande, AZ (Fig. 1). Santa Cruz is a 1.36-Gt (1.5 billion st) porphyry deposit averaging 0.6% Cu, of which 65% is oxidized, concealed beneath post-mineral alluvium at depths of 365-914 m (1500-3000 ft). The Bureau and the SCJV will evaluate in situ mining as a method for extracting copper from this previously unmined deposit. Research objectives of the Santa Cruz project are: - to demonstrate that an in situ research test can be operated in an environmentally acceptable manner ; and * to operate an in situ well pattern long enough to develop information on copper recovery and economic feasibility data. In situ mining of copper from undisturbed deposits has not been attempted commercially. There are several potential advantages with in situ mining: less exposure of miners to hazards, lower pital costs for the mine and plant and lower operating costs. In addition, there are no pits, dumps or tailings, which means less environmental impact.

Jan 1, 1991