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By R. David Williams

Old mine workings are found throughout the Western United Sates on lands administered by the U.S. Bureau of Land Management (BLM), U.S. Forest Service (USFS) and private lands. Some of these mine workings date back to the late 1800s. There may be as many as 100,000 sites on lands administered by the U.S. Forest Service and Bureau of Land Management. The Bureau of Land Management has worked with the State of Montana and other agencies to identify and prioritize these sites on BLM administered lands. Following completion of the AML inventory work, the Bureau began an aggressive program to clean up priority sites. This presentation will highlight completed work as well as work in progress on several sites.

Jan 1, 2000

By M. G. Hester

The ore reserve modeling of stratiform uranium deposits to be mined by selective underground mining methods must be done with consideration of the erratic nature of the ore forming processes that produced the mineralization. Estimation methods that model the uranium grade as a smooth transition between high grade and low grade drillhole intercepts tend to greatly overestimate the ore tonnage. Care must be taken to first establish realistic ore pod geometries and then estimate the grade of the reserve units within the pods.

Jan 1, 1985

By John E. Good

A new coal boom is under way in western Canada. As recently as the mid-1960's, the coal industry in western Canada was considered stagnant and, by some people, dying. But Japan's growing need for coking coal, which became more pronounced in 1966, sparked great interest in western Canadian reserves.' As a result of a rapidly expanding export market and growth in domestic demand, Canadian coal production spurted to 16.6 million tons in 1970. Production in 1965 was 11.5 million tons. Today, about 60 percent of Canada's output comes from western Canada, but by 1975, 87 percent (23.1 million tons) is expected to come from this area, and 96 percent (68.3 million tons) by 1990. Opening, developing and operating new coal mines to meet the needs of a rapidly expanding market for western Canadian metallurgical coals pose some unique and difficult problems. Covering nearly every aspect of opening properties in remote areas, the problems are met in exploration, transportation, construction, mine operations, coal preparation, manpower and ecology. Paul Weir Company has been involved as coal consultants on various projects in western Canada for some years. In presenting this paper, we make no attempt to present an in-depth or detailed analysis of any one specific situation. Each has, or would have, its own peculiarities or characteristics, both physical and economic. Instead, the objective is to provide for those not intimately

Jan 1, 1972

By John V. Beall

A completed feasibility study executed by an independent agency can benefit a company in two ways. Inside the organization, it verifies the project staffs ideas and their concept of the facility. Outside the company, it can be utilized to obtain equity partners, debt financing, and other forms of credit. It is advisable to bring in a project execution contractor for the feasibility study. A project execution contractor is able to work with engineers to develop the project concept, process flowsheet, and best utilization of the site. By getting an early start on understanding a company's policies and working methods, a project execution contractor saves the company money since it does not have to go through the educational buildup twice. The contractor is a specialist in putting together a bankable document that can be taken to a financing source. It answers all the agency requirements on the first pass. In addition, the contractor can advise an owner on likely financing sources since he works on the worldwide market every day. A less obvious advantage of including the contractor in the study and predevelopment buildup stages is the importance of coordinating finance and technical input. The financing source influences equipment specifications, procurement, logistics, project schedule, cash flow, and liquidity. There are many surprises in store for any manager of a large international project involving worldwide financing and purchasing. The job does not have to be made more difficult by bringing in a contractor after all predevelopment steps are taken. The contractor can still work if the predevelopment steps have been done, even if he does not agree with them. But early contractor involvement is the preferable solution.

Jan 10, 1980

By Lewis L. Oriard

The authors outline the development and application of blasting methods put into use 11 years ago at the Berkeley Open-Pit Mine, Butte, Montana. The blast design uses a very short delay (5 milliseconds) between detonation of explosives charges, a feature challenged several times in principle despite its success for Anaconda. Concern is expressed over the categorical rejection of very short delay blasting which can make the difference between success and failure of major mining operations. There is ample evidence to show that the method can be used successfully and not violate the concerns of the public.

Jan 1, 1980

By Leon D. Keller

Fine screening, as discussed in this paper, pertains to the use of the Rapifine DSM Screen to make a 65 to 325-mesh separation at production tonnages. The greatest number of Rapifine Screen installations are in magnetic taconite plants where the unusual relationship between the grinding mill, cyclone classifier, magnetic separators, and fine screens makes the Rapifine Screen application unique. Since the initial fine screening installation on magnetite in 1961, (1) additional installations and further testwork have contributed to the fund of information which is the basis of this paper. The addition of fine screens to the grinding-classifying circuit of a magnetic taconite plant creates a change that effects all components of the circuit. Pine screens in a non-magnetic plant have also been investigated, but here the benefits have not' been as clearly defined. Screens classify according to the particle size. Hydrocyclones classify by a combination of particle size and particle weight. The change in the type of classification minimizes overgrinding of the mineral. The resultant savings in grinding power can be used to increase the throughput, upgrade the product, or increase recovery.

Jan 1, 1971

By Jens Classen

"GENERAL PROJECT DATA The Sparvo Tunnel belongs to “Variante di Valico” project, a new 65 km highway link between Bologna and Florence, designed to renew the existing A1 route and to connect in a faster way Bologna and Flor-ence. It is composed of a 2,5 km twin tunnel excavated in a complex geological context, characterized by the presence of a series of surface landslides and methane gas. The gradient is 2.6 % and the minimum radius is 1’400 m. The internal diameter of the precast seg-ment lining, equivalent to the final section of the tunnel, is 13.6 m. MAIN TBM SPECIFICATIONS TBM Earth Pressure Balanced S-574 “Martina”, manufactured by Herrenknecht, has a theoretical excava-tion diameter of 15’615 mm. It is equipped with a conical shield 12.2 m long and four back-up gantries. The total length of the machine is approximately 130 m, weighing approximately 4’500 tons. The total installed power is 16’800 kW. The main drive has a diameter of 8’700 mm and has a triple axis roller type bearing equipped with a labyrinth system including 4 sealing lips. TIME SCHEDULE OF INITIAL TBM DRIVE A time schedule of the initial TBM drive is presented in the following list: •,August 25, 2011: start of the excavation of the 1st drive of the Sparvo tunnel •,October 29,2011: stop of the advance of the TBM for gear oil contamination and clogging •,October 29 to December 20, 2011: repair works on the main drive system and modifications on the conditioning system •,December 20,2011 to July 25, 2012: restart excavation of the 1st drive (north tunnel) and its breakthrough •,July 25 to November 29, 2012: 180° turning of the TBM, detailed check of the main drive seal-ing system and fixing problems on gear boxes, race ring, clamping ring and cutting wheel •,November 29,2012 to July 24, 2013: excavation of the 2nd drive (south tunnel) and its break-through •,August 2013 to July 31, 2014: disassembly of the TBM (first 4 months) and standstill of the jobsite for structural issues on precast concrete lining of the tunnel •,July 31, 2014 to March 10, 2015: inspection, dismantling and packaging of each part of the main drive (flange ring, gear box housing and main bearing). The various phases are described hereafter in detail."

Jan 1, 2016

By J. Tavares

It is no mystery why the mining industry has such lofty safety standards. In dealing with Mother Nature and gravity, the combination of the two can create significant hazards from high wall and tunnel collapses to huge landslides. The loss of production from a major disruption could be enormous. The price tag on the loss of human life is immeasurable. The evolution of geotechnical instruments and software has been ongoing for years. But the biggest innovations have occurred during the era of cell modems, internet, and wireless networks, allowing for real time data and alarms to be delivered globally anywhere and anytime to one?s computer, laptop and smartphone. Yet in some ways you can thank the urban construction projects for developing much of the technology in use by today?s mines. Due to the density of population and the billions in dollars of structures and infrastructure in cities throughout the US and the world, urban projects have faced intense scrutiny for years. Out of this scrutiny was born the necessity of real time automated monitoring of instrumentation and sensors, a defence against catastrophic failures, and real time early warning systems through alarms that can and do saves lives. It is also possible to identify areas of concern with subsequent remediation prior to failure.

Feb 23, 2014

By D. E. Munson

The Waste Isolation Pilot Plant (WIPP) Project was established in 1975 by the Department of Energy (DOE) under Public Law 193 to develop the necessary technology for safe disposal of radioactive wastes from the defense programs of the U.S. The technology development involves extensive theoretical, numerical, and laboratory programs, as well as construction of the WIPP facility in southeastern New Mexico for in situ testing and waste storage demonstration. If after the demonstration, the facility is found to comply with regulations of the Environmental Protection Agency, then the facility will become a repository for Transuranic (TRU) waste. The underground portion of the facility is 655 m beneath the ground surface in massive natural salt deposits of the Salado formation, as shown in Figure 1.

Jan 1, 1991

By Feridon Ghadimi, Saeed Mojeddifar, Massume Khavari

Separation of geochemical anomalies from background is an important and essential issue in the exploration of mineral deposits. Statistical methods are used to separation of anomaly from background. Fractal/multifractal and singularity methods are very suitable for the separation of weak anomalies. For interpolation, various methods could be used such as most distance-weighting methods, kriging, spline interpolation, interpolating polynomials, and finite difference methods. This paper addressed application of multifractal techniques together with finite difference procedure to detect the anomalous regions. Fractal models such as concentration–area, spectrum–area, and singularity index model were selected to identify Pb–Zn anomalies. In this research, 170 samples from 33 boreholes were taken in the Haft-Savaran area and analyzed for determination of Pb–Zn anomaly. Singularity method was a suitable method for separating Pb and Zn anomalies. Also, the results showed that the geochemical anomaly has occurred along NE–SW trend and is consistent with the sulfide mineralization process and the faults of the region.

May 18, 2020

By S. J. Root

The mineral processing industry supplies raw materials to a wide variety of manufacturing sectors. Large companies such as Ford, Microsoft, and Johnson&Johnson have pledged carbon neutral supply chains in the coming decades, leaving suppliers to reevaluate their energy sources [1–3]. National Renewable Energy Lab [4] has partnered with over 700 organizations with similar goals in mind. The energy needs are broad in scope in the mineral processing industry. Generation IV of nuclear reactors, which is currently under development in both the private and public sector includes a class called microreactors like the small modular reactor XEnergy plans to install at Dow Chemical’s Gulf Coast facility by 2023 [5]. As the name implies, these are smaller than the utility scale nuclear power plants in operation today, and are intended to be more versatile. A specific reactor core design, along with modules could be selected to fit a certain application without needing to design a greenfield power plant. Basic water cooled designs could easily supply shaft work, electricity, and low grade process heat to a facility. More advanced designs, such as molten-salt-reactors and high-temperaturegas-reactors can achieve higher temperatures needed for ore roasting. Similarly, these reactors could produce hydrogen by high temperature electrolysis to use as combustion fuel and reducing atmosphere in blast furnaces.

Feb 1, 2023

By J. C. Stankus, R. Ochsner, B. Hanson

"Bull Mountains No. 1 mine of Signal Peak Energy made another success in its 4 Right pre-developed recovery entry on March 23 and 24, 2015, after the first successful cut-through and shield retrieval of 3 Right pre-developed longwall recovery entry in 2014[1]. Under the same geological conditions, the major difference of 4 Right and 3 Right is the 600 psi Unconfined Compressive Strength (UCS) value of light-weight concrete in 4 Right versus 800 psi in 3 Right. In addition, one more recovery chute was added in 4 Right. The unique geological conditions in this mine include: (1) the low overburden of approximately 200-260 ft, (2) prevalence of roof joints parallel to the face in the sandstone/siltstone dominated overburden, (3) proximity of the Rehder rider seam to the bench Mammoth coal seam, and (4) prompt surface subsidence with the face advancement. The 4 Right recovery entry was 42 ft wide and developed in two stages, 20 ft wide in the inby Phase I, and 22 ft wide in the outby Phase II. The entry roof was reinforced with steel wire mesh/non-metallic recovery mesh, primary bolts, and high-capacity supplemental SUMO cables. After all the support was installed, the entry was completely backfilled with specially designed, cuttable, low-density cement. It took approximately half time to easily cut through the concrete with less dust in 4 Right as compared to the concrete-cut-through time in the 3 Right. The updated study further explored the nature and mechanism of effective roof control approaches in the pre-developed recovery entry of this unique geology mine, aiming at providing the safest working environment for protecting the miners. GEOLOGICAL AND MINING CONDITIONS OF THE RECOVERY ENTRIES Bull Mountains No. 1 mine is located 30 miles north of Billings, Montana, and currently mines bituminous coal from the Mammoth coal seam. The mine employed a conventional recovery face in Panel #1 and pre-developed recovery entries in Panels #2, #3, and #4 (Figure 1). The typical mining and geological conditions are as follows:Overburden Depth The overburden above the Mammoth coal seam in the #1-#4 Right recovery areas is approximately 200-260 ft. This low cover, in combination with specific roof geological features (especially the prevalent roof joints and proximity of rider seam), constitute unique ground movement characteristics when the longwall face advances into the recovery entry if no sufficient roof support is installed."

Jan 1, 2016

By Kenneth J. Edmiston

The objectives of this paper are: to review the current status of chloride leach processes for sulfide concentrates, to make an evaluation as to the applicability of chloride leaching for replacing pyrometallurgical processes and to comment on recent advances in construction materials. The paper does not delve in detail on process chemistry. Sufficient references are presented on each process to allow the interested researcher to obtain process chemistry details. GENERAL The fact that chloride oxidates can solubilize base metals from sulfide concentrates has been known since the 1880's. The work of Hoepfner in 1902 was particularly accurate for its time with regard to the chemistry of chloride solutions. Recent work has dealt with the understanding of chloride extraction thermodynamics by modelling the behavior of metal chloride complexes. In the last several years several excellent review articles and symposiums have been issued covering chloride chemistry (1 thru 6).

Jan 1, 1984

By R. R. Klimpel

The use of chemical reagents in flotation has been studied in great detail, e.g. (1, 2, 3, 4). Important progress has been made on the understanding of surface chemistry concepts involved in flotation. However, such scientific studies are often very complex even for rather simple idealized systems. Therefore, the deve- lopment of predictive or quantitative tools for plant engineering evaluation is still in the evolutionary stages. Until further progress in fundamental work is achieved, the operating engineer is faced with semi-empirical physical testing of reagent changes on several sizes of the actual equipment under study to be confident of the economic viability of any change.

Jan 1, 1980

By P. Soros

Rich iron ore deposits were discovered during the 1960's in the mountain range of Serra dos Carajas, State of Para, Brazil, near the headwaters of the Tocantins River some 400 miles southwest from the state capital of Belem. (See Fig. 1 and 2). The key to the successful exploitation of this deposit was the development of an efficient an economical transportation system. The rugged terrain, and the dense tropical vegetation of the Amazonian jungle and the irregular coastline with its high tidal range presented severe obstacles to the planning and building of such system. Starting in 1972 extensive surveys and studies were carried out by Soros Associates on behalf of CVRD to determine the optimum way of transporting the ore from the mine site to the markets, most of which are located overseas. Overland transportation to the coast, loading into seagoing vessels and the ocean voyage to the ports of destination was treated as an integrated system in these studies.

Jan 1, 1986

By A. G. Ulsoy

In recent years there has been an Increasing Interest In the application of automatic control theory to mineral processing systems, and numerous applications of mineral process control have appeared in the literature. A general approach to the synthesis of mineral process control systems is presented. The first phase of the control system design consists of specifying the control objectives, process variables and their interactions; these topics will be discussed with specific reference to mineral processing. The second phase Is con¬cerned with selection of control strategies algorithms, instrumenta¬tion, and other components of the control system and is discussed at length. These concepts are then illustrated by a flotation control case study.

Jan 1, 1981

By Alexander Darío Huamán Ccorahua, Cayo Fernando Soto Buendía, Jhonatan Raphael Rojas Ventura

Lithium is a top-quality mineral in the energy market, with growing demand. It has many applications in medical, nuclear, and energy industries. The purpose of this article is to quantify and analyze the economic potential and projected global demand for lithium annually. It aims to determine Peru’s (specifically Puno) positioning in the global context in 2025 and 2030. The article also seeks to identify the main regulatory, environmental, and social challenges to sustainably exploit lithium in Peru. The study employs applied research (mixed approach), descriptive-correlational scope, and observational, crosssectional design. The methodology demonstrates the use of statistical techniques to model and make predictions about this energy-transition metal. Academic sources were reviewed to enable a comparative approach and projection into the future of lithium for development in the mining industry. In the last 10 years, lithium demand has grown, noting a 600% increase in the economy and projected annual growth of +26%. Exponential growth in resources is projected, where econometric, R-multivariable and R-linear models estimate that Peru could supply 1.5% in 2025 and 3% in 2030 of global lithium. Estimated growth of 5–15% in socio-environmental conflicts is projected with the start of lithium exploitation (Peru – Puno). The global potential of lithium demonstrates exponential growth. Lithium reserves in Puno - Peru would rank 13th between 2025 and 2030. It is necessary to establish a clear regulatory framework to avoid excessive increase in socio-environmental conflicts.

Feb 1, 2024

By Stanley J. LeFond

The Republic of Botswana, one of the newer countries of southern Africa, attained independence on September 30, 1966. It covers an area of about 225,000 square miles (582,000 square kilometers) which makes it slightly larger than France, or slightly smaller than Texas. It is bounded by Zimbabwe, the Republic of South Africa and Namibia, including the Caprivi Strip. Angola and Zambia are close neighbors. (Map 1). Botswana lies at the center of the southern African plateau at a mean elevation of 3,300 feet (1,000 m). It is a natural habitat for most species of African fauna. The rolling sands and extensive grasslands of the Kalahari Desert cover the southwest. The climate is sub- tropical. Summers, although tempered by north- easterly breezes, are hot, but mean maximum temperature seldom rises above 100°F (38°C). Winters are dry with wide temperature variations, which often give rise to frosts.

Jan 1, 1981

By R. R. Kallu

The current 120 psi seal design and evaluation practices are mostly based on simple analytical solutions. Considering the simplistic assumptions and limitations involved in simple analytical solutions and practical difficulties involved in conducting conventional full-scale explosion tests for evaluating 120 psi seal designs, there is a need for developing new scientific methods and engineering practices for design, analysis and evaluation of mine seals.

Jan 1, 2010

By Guillermo Krstulovich

Pillar strength is a fundamental variable in the design of room and pillar mining. A number of researchers have investigated the strength of mine pillars by loading cubical, cylindrical and rectangular model pillars to failure in a compression testing machine (1). Several of these researchers have observed an increase in the compressive strength of model pillar with an increase in friction at the platen-specimen interface (2, 3, 4, 5). It has been postulated that the friction prevents lateral expansion of the specimen, thereby exerting a confining pressure at the interface. Seldenrath and Gramberg in their work with cylindrical specimens of limestone and marble noted that the effect of clamping the ends of the specimens, i.e., to restrict lateral movement of the specimen face, was to increase the compressive strength about 10% for marble and from 50-75% for the limestone, as compared to the same type of specimens when tested with the end planes free (6). No attempt was made to determine the confining pressure exerted by the clamps. In recent years, Bureau of Mines has conducted an extensive study, similar to Seldenrath and Gramberg's, with dog bone specimens. The confining pressure exerted by the clamps was determined and an increase in the compressive strength with increasing confining pressure noted (7, 8).

Jan 1, 1970