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By John L. Halls

INTRODUCTION In this section, it is assumed that the reader is an engineer with sufficient training in underground mining work, preferably with budgetary control, to understand the mining methods outlined in other sections of this handbook. The mining-method descriptions are not repeated herein; only sufficient information is provided to enable the reader to comprehend the development of the costs presented. All costs are in 1977 US dollars, except where explicitly stated otherwise. CAPITAL INVESTMENT The capital investment in the underground mining portion of any mining property includes the following: 1) The development of original access involving adits, shafts, declines, etc. It includes the necessary equipment for transporting men, materials, and rock. 2) The purchase of mine equipment including loaders, underground haulage equipment, fans, pumps, electrical distribution, surface facilities associated with the underground mine, etc. 3) Sufficient preproduction mine development to assure steadily increasing production after startup. De- pending upon the mining method used, the preproduction development should provide a supply of three months to one year of ore that is developed and is ready to be stoped. Underground development also includes excavations other than shaft stations, loading pockets, sumps, etc., which usually are associated with the means of access and are excavated by the contractor. These excavations could include a crusher cavern, an ore- storage pocket, and underground workshops that may or may not be included by the shaft-sinking contractor. Portions of these could be delayed until after production begins, but it is preferable to complete them during the development phase, so there is no interference with the production buildup. 4) The staff and labor costs for all phases from inception through final production. 5) The provision of mine-surface equipment and facilities strictly applicable to the underground portion of the operation. The required facilities include a changehouse with a lamp room, a first-aid station, compressors, an electrical substation, workshops, a ware- house, water pipelines to the concentrator, water storage tanks, explosive storage, etc. A concrete-batch plant, a sand-fill plant, and boilers for heating may be required. 6) Other direct and indirect costs. 7) Engineering, design, and procurement costs. 8) Contingency allocations. 9) Contractor's fees, startup costs, and owner's costs. Original Access As part of a study for the US Bureau of Mines, Dravo Corp. conducted an extensive literature research survey covering underground operations in the United States between 1963 and 1973. Table 1 is compiled from the section of that study pertaining to the types of access to underground mines. Table 1 does not include distances attributable to the deepening of existing shafts, nor does it include shafts bored by raise drills or downhole machines that need existing underground workings for the disposal of the cuttings. During the period under review in the report ( 1963 through 1973). concrete-lined circular vertical shafts were the predominant means of providing the first access to a new underground mine; these shafts accounted for 80% of the original access in terms of the number of accesses completed, and 75% in terms of the total verti- cal linear distances. The inside diameters of the conventional circular shafts ranged from 3.7 to 7.0 m (12 to 23 ft). Most (72% ) of these conventional shafts were for production,

Jan 1, 1982

By Terence G. McCusker, E. Roy Anderson

A four-mile length of interceptor sewer tunnel in Manhattan has finished sizes ranging from 10'6" to 14'6" horseshoe. Mixed face conditions were anticipated in three areas and encountered in five. All were short but since the tunnel lies well below the water table and failures would involve important utilities, major structures and human lives, great care had to be exercized in choosing a construc¬tion method. Chemical consolidation was selected as the best approach with compressed air working as a backup system. Initially grouting was accomplished from within the tunnel, but treatment from the surface was more successful and was later adopted. The soils consisted largely of impermeable weak silts and it was found possible to inhibit access of water to this material so that it could be controlled by breasting within the tunnel without loss of stability. It is concluded that in the interlayered permeable and impermeable soils encountered, chemical grouting would successfully stabilize the working face. INTRODUCTION An interceptor sewer is currently under construction along the entire length of the west side of Manhattan. When complete, the tunnel will intercept and divert to a treatment plant (also under construction) a daily flow in excess of 200 million gallons per day. About 9 miles of the interceptor sewer is in tunnel and the remain¬der is cut-and-cover construction. The tunnel is almost entirely in Manhattan schist but where its alignment crosses major faults at comparatively shallow depths, mixed face and earth conditions are

Jan 1, 1997

By Michael Karmis

"In December 2011, the U.S. Attorney’s Office for the Southern District of West Virginia, the U.S. Department of Justice, Alpha Natural Resources (ANR) and Alpha Appalachia Holdings entered into a nonprosecution agreement related to the explosion at the Upper Big Branch Mine (UBB) that killed 29 miners. This coal operation was owned by Performance Coal Co., an affiliate of Massey Energy Co., which was acquired by ANR in June 2011, more than a year after the UBB explosion. Pursuant to the agreement, ANR agreed to:• Establish a trust within 120 days.• Pay a total of US$48 million into the trust to be used solely to fund and administer research and development (R&D) projects to improve mine health and safety.• Administer the trust by three highly qualified individuals with academic and/or professional backgrounds in mine health and safety.In April 2012, the Alpha Foundation for the Improvement of Mine Safety and Health was created. The three directors - Michael Karmis, president; David Wegman, vice presidenttreasurer, and Keith Heasley, vice presidentsecretary - approved a plan to expend both the interest and principal of the trust, aiming at an 8-10 year research horizon. The foundation also appointed David Belden, an experienced manager of nonprofits and professional associations, as the first executive director of the foundation. The IRS approved the foundation’s tax-exempt application, as described in Section 501c(3) of the Internal Revenue Code, on Dec. 18, 2012. The board established guiding principles of the foundation, which are as follows:• Mission: to improve mine health and safety through funding R&D projects to qualified academic institutions and other not-for-profit organizations.• Vision: to enable miners in the future to be free of work related injury or disease by the implementation of the results of the projects funded by the foundation and undertaken by the best researchers from any discipline that can contribute. The foundation is now approaching its third year and regularly posts updates, including semi-annual reports, to its website (www.http.alpha-foundation.org/), which serves as the main medium for communication with the broader stakeholder community"

Jan 1, 2014

By A. Bascetin

The human requirements have increased rapidly depending on population density and urbanization thus industrialization has grown steadily. As a result of the situation, the greenhouse gas emissions into the atmosphere and the global warming have increased slowly. Today this effect has continued to increase. Therefore, the effects of greenhouse gases in all areas of production must be controlled. The study presents the methods of determination the CO2 emissions (CO2-e) and energy consumption in aggregate production. The aggregate constitute approximately 70% by volume of concrete that has widespread use as construction material in the world. One of the most important elements in today's terms is sustainable use of resources and minimum CO2 emissions (CO2 + CO + NOx + CH4.vb.) at every stage of production of aggregate. Therefore, these elements must be taken into consideration in the aggregate production standards. The choice of production method of aggregate is very important for optimum use of energy and effects of greenhouse gas emissions. So the properties of the aggregate material must be known well to obtain the target. Within the scope of this study, the unit value of CO2-e that release when the production of aggregate in different formations is determined for our country. Thus, the effects of green house gas emission can be evaluated according to the characteristics of material in aggregate production planning. In this study, energies consumed during the production of aggregates at a quarry in Istanbul Cendere region were investigated by taking the different formations encountered at the quarry into consideration. The unit CO2 emission values per ton of produced aggregates were calculated as a result of this investigation. Besides, energy consumption values of previous months at this quarry were taken and the unit CO2 emission values were also calculated.

Jan 1, 2011

By J. E. Urosek

The Mine safety and Health Administration (MSHA) formed the Mine Ventilation Bleeder and Gob Training Committee in 1993. This committee was charged with developing a training course designed to enhance the knowledge and understanding of practical bleeder ventilation systems. The course will probably include a discussion on the theory behind bleeder system design, an in-depth look at the strengths and weaknesses of the basic bleeder system types, case studies, and a review of the systems currently in use. A database on active underground bituminous coal mines, gob areas, and the bleeder systems presently used was developed from questionnaires distributed to nine Coal Mine Safety and Health (CMS&H) districts. Representative systems were selected for thorough investigation to develop case studies. This paper introduces some of the material to be included in the course, including a description of basic bleeder system designs, a review of a portion of the database, and facts about the gob areas and bleeder systems investigated for the development of case studies.

Jan 1, 1995

By R. K. Steinhorst

Multivariate cluster analysis, MANOVA, canonical analysis, and discriminant analysis of hydrochemistry data were used to investigate the directions of ground water movement in basalts in the vicinity of the Hanford Reservation, Washington. The statistical analyses indicate that the hydrochemistry of the ground waters in these basalt formations is distinctly different on each side of the Columbia River. This suggests that the river is a ground water divide or that the river is roughly coincident with a hydrogeologic barrier boundary. The statistical procedures used in this study constitute a quantitative means for differentiating ground waters according to hydrochemistry.

Jan 1, 1990

By Franziska Wolf, Rainer Ellmies, Helmut Mischo

"Mining is an important part of the economy of Namibia. In 2016, 11.1 percent of the GDP was the result of mining activities with 22 active mines (The Chamber of Mines of Namibia, 2016). Only one of them consists of an underground mining operation.The global annual production of fluorspar is approximately 5.4 to 6.3 Mt (6 to 7 million st) (U.S. Geological Survey National Minerals Information Center, 2017). Okorusu has produced on average about 45 kt/a (50,000 stpy) in recent years (U.S. Geological Survey National Minerals Information Center, 2015).The Okorusu Mine is Namibia’s only fluorspar mine. Fluorspar was mined in an openpit mine with four individual pits (A-D) since 1980. In 2014, the mine closed due to the increased stripping ratio and beneficiation problems. The mine assets were bought by Gecko Namibia. Currently, Gecko uses parts of the processing plant for beneficiation of graphite from a neighboring mine. Figure 1 shows a panoramic view with the four pits and the mine village.The intent is to develop a concept for the further underground development of the mine. There are still about 6.3 Mt (7 million st) of measured resources left in the deposit, with an average grade of 27.5 percent CaF2. This study focuses on the underground mine design. The above-ground plant and facilities are considered as remaining unchanged.For solving the task to design the mine, a site visit for data collecting was conducted. Resource estimations were calculated based on existing drill data, and consequently, block models were created. The development of the mine design included the selection of the most suitable mining method, mining technology and mine organization. Moreover, some economic considerations are pointed out, followed by a profitability assessment."

Jan 2, 2018

By Dan Witkowsky

In an increasingly environmentally conscious world, mining's importance to society has often been misunderstood and even maligned by the public. Extreme and impractical ideas have often been presented to children because of the lack of accurate, timely resource materials available to educators. In the late 1960s. two mining engineers, S.P. "Pi" Warren and C.L. "Lindy" Barker, became aware of this situation. They proposed to develop a summer field course to provide a factual overview of the minerals industry for teachers. The pair believed that teachers could become better informed to educate students, and future generations, about mining. These two Colorado Mining Association (CMA) members felt that such a course could reduce much of the misunderstanding about this vital industry. This could be done by providing a balanced perspective of mining, not only for kindergarten-through-grade-12 teachers, but also for the students they would be teaching during their careers. Students who better understood the minerals industry could better formulate an unbiased view of it. The course would seek recognized authorities from industry, academia and government who would lecture in their respective fields of expertise. The course would provide a total concept of the coal, aggregate, metals and industrial minerals industries. It would include geology, geophysics, exploration, mining, processing, marketing, product applications, economic, mining history, careers, and environmental responsiblity. When possible, site visits would permit educators to view operations and to meet the men and women who are industry leaders. Teachers would pay a small tuition fee. The balance of the program expenses for each teacher would be paid through scholarships provided by industry and individuals. The "total concept" idea obtained the support of the minerals industry. The support of CMA's Education Committee and the Colorado School of Mines (CSM) was obtained in 1968. Colorado's Commission on Higher Education approved teacher recertification credits through CSM's Office of Special Progams and Continuing Education for those successfully completing the program. The first six-week series of classes presenting the total concept of the indus¬try was held at CSM in 1969. In 1977, the CMA Education Foundation Inc. (CMAEF) was established as a Colorado nonprofit corporation. The "Total Concept of the Mining Industry" (Total Concept) course was placed under its sponsorship. CMAEF is dedicated toward this continuing education program (Table 1). In 1994, the course was streamlined to four-weeks for six hours recertification credit.

Jan 1, 1997

By Claus Becker

The new, 2.600 m long pipe under the river Elbe in Hamburg/Germany required for 2 traffic lanes, emergency lane and space for utilities a boring diameter of 14,20 m(46,6 ft). According the geology (glacial deposits consisting of clay, sand and marl, all containing big boulders) a Slurry-Shield with crusher was selected. With a minimum cover of 7 m and a maximum pressure of 5,6 bar extensive ground treatment was necessary to make the drive feasible. The machine contains a lot of new developments. The drive was finished in spring 2000 so all experiences can be reported. A special risk sharing contract avoided completely litigation.

Jan 1, 2001

By M. P. Roy, P. K. Singh, A. K. Mishra, Ashish K. Vishwakarma, Vivek K. Himanshu

Ground vibration is one of the major hazards produced by rock-blasting operation. The accurate prediction of vibration is necessary for designing controlled blasting parameters. The existing vibration predictors consider maximum explosive charge weight per delay and distance as the parameters responsible for ground vibration. These predictors are based on the assumption that the geometrical parameters of the blast will be constant for a site. However, the mining sites with bigger production targets have varying geometrical parameters to suit the excavator utility. Accordingly, the other blast design parameters will also have an impact on ground vibration intensity. A principal component analysis is a dimension reduction technique. This technique along with multivariate logarithmic regression has been used in this paper to predict the ground vibration. The technique has classified the blast design parameters into four principal components. The regression with the scores from these principal components has been carried out. The evaluation of the model performance of predictors along with the existing empirical predictors has been carried out using R2 and RMSE values. The evaluation suggests that the predictor with logarithmic regression followed by principal component analysis gives better performance with respect to the existing empirical predictors.

Jul 30, 2022

By Craig M. Sams

Dry grinding circuits and factors influencing the selection of the most appropriate grinding system for a given ore selection are discussed. Comparisons of the drying, grindability, installed costs and operating costs are presented for several grinding systems.

Jan 1, 1994

By George B. Griswold

The two most stringent parameters for in place fracturing of rock are the lack of any initial void space in the rock which to expand into and the ability to gain access only through drill holes. These two restrictions have proven so severe that as of today the only proven techniques for efficient fracturing are the contained nuclear detonation and hydrofracing. Both of these methods have highly developed technologies for their application. Hydrofracing has been a standard oil field practice for two decades, and the experience gained from a couple hundred underground nuclear detonations has resulted in a thorough understanding of the phenomenology of cavity and chimney formation. What is still lacking is a practical method to create a suit- able degree of fracturing for those ore bodies which do not meet the application criteria for either the nuclear explosion or hydrofracing. Nuclear applications must be restricted to thick ore deposits so as to take advantage of chimney collapse height--preferable in excess of 200 feet thick. Other requirements such as ground shock, containment, and radioactive contamination further reduce the number of sites that prudently can be selected.

Jan 1, 1969

By Omar. M. Arafat, Edgar Pérez, Kyle. M. Bartholomew, Robert. E. McIvor

The “circulating load” confounds understanding of ball milling circuits. Conflicting opinions exist as to its role. Should it be high, or low? Why does it even exist? It is commonly accepted in the plant as a given, the outcome of largely unknown factors. As such, it may often go unmeasured or even ignored. This paper describes the importance of the circulating load in wet ball milling circuits. It is characterized not only in terms of solids mass flow (or ratio of mass flows), but also by its other key physical characteristic, its size distribution. Its effect on grinding circuit performance is explained. The equipment application design steps to achieve a desired circulating load, in terms of both its mass flow and size distribution, are described. Finally, its pivotal role in grind control is specified. Our goal is for the reader to come away with a fresh understanding of the role of the circulating load in wet ball milling circuits, including how and why it should be measured and managed.

Feb 22, 2026

By Alan J. Michaels

The paper addresses the problem of the high costs of accidents ad how AMAX Inc. - a diversified natural resources company - has managed to control its losses through a tri-thrusted approach of: (1) management commitment, (2) methods of implementation that are tailored to each division or local unit, and (3) a reward system for outstanding performance. Specific attention is focused on the Corporate Loss Prevention Department's "10 Point Program for Loss Prevention Management".

Jan 1, 1981

By Alfred A. Roetzer

In several sections of the country new demands are being brought bar cement users. Among these the demand' for truck shipments; and palletized loads present new problems that do not lend themselves to sample solution. In fact these demands have far-reaching effect in the way bagged cement might be marketed. Early solutions of palletized truck loads filled from existing packing and loading facilities have resulted in' slowdown in packing, additional labor and space for palletizing, considerable experimentation in type and construction of pallets, and usually far from optimum truck handling and loading methods.

Jan 1, 1961

By D. R. Spears

The Bureau of Mines has investigated the fundamental aspects of shear-flocculation using a rapid, in-situ particle size analyzer. Silica was stirred in the presence of an aliphatic amine to determine the effects of collector coverage, stirring speed, and solids concentration on the kinetics of shear-flocculation. The results showed that shear-flocculation is a two-stage process. In the first stage, mean particle size increased rapidly in the first 1-2 min of reaction; in the second stage, an equilibrium was set up between the rate of floc growth and floc decay. Collector dosage affected the position of the equilibrium by altering the number of surface sites for particle-particle attachment. A minimum stirring speed was necessary for shear-flocculation to occur and was dependent on solids concentration and collector dosage. This speed was the minimum necessary for particles to overcome the electrostatic energy barrier which kept conditioned particles dispersed. Larger particles flocculated more rapidly. At very high stirring speeds, large flocs became unstable, resulting in a narrowed particle size distribution in the slurry.

Jan 1, 1993

By G. Bulut, Ü. Yenial

"The use of recycled water in flotation has significant effects on flotation and selectivity because the recycled water contains many dissolved compounds and ions that alter the chemistry of the system. In this study, the effects of calcium, magnesium and sulfate, which are abundant components in recycled water, were investigated on galena, sphalerite and pyrite flotation using pure minerals and a complex sulfide ore by conducting bench-scale flotation, microflotation and zeta potential measurements. The bench-scale flotation tests indicated that higher recoveries of galena and sphalerite are obtained when water is recycled, due to higher concentrations of ions in recycled water. However, there was a critical ion concentration for galena recovery. The microflotation tests showed that galena recoveries at different pHs in recycled water are lower than in tap and distilled water. Pure sphalerite recoveries improved in recycled water in the bench-scale test with ore. Pure pyrite was depressed with recycled water as well. Zeta potentials became less negative with increased calcium and magnesium ion concentrations due to their adsorptions, and the presence of sulfate ions was seen to increase the negative charges of sphalerite and pyrite, conversely for galena. IntroductionWater is among the most important elements for mining and mineral processing. The distance to water sources is one of the major factors for mine site selection. The mining and mineral processing sector needs and consumes large quantities of water. In Chile in 2014, the copper mining sector alone consumed 12.7 m3/s fresh water for 1.189 tons of ore processing, and recycled 74 percent of the consumed water (Chilean Copper Commission, 2015). A plant that does not reuse or recycle any water will require 1.9 to 3.0 m3 of water per ton of ore processed (Gunson et al., 2012). Many stages of mineral processing, such as grinding, gravity concentration, dense medium separation, wet magnetic separation, flotation and hydrometallurgical operations, use large volumes of water (Schumann, Levay and Ametov, 2009).In mineral processing plants, the process water is recycled from the tailings dams, thickener overflows, and dewatering and filtration units. Wet concentration processes can require large quantities of water. Flotation, the most common process, typically takes place at 25 to 35 percent solids by mass. Most flotation plants practice at least some water reuse and recycled. Modern mines and mineral processing operations generally aim for zero water release (Levay, Smart and Skinner, 2001). In most cases, water quality has been found to affect flotation performance, and this interaction remains under investigation."

Jan 1, 2016

By F. W. Pereira

The Montana Talc ore body was discovered in the summer of 1983, in the Gravelly Range, approximately 25 miles south of Ennis, Montana. Initial drilling indicated a plus-million-ton ore body of high-purity talc. Preliminary analyses were performed on the ore cuttings, .including chemical analysis, brightness measurements, and microscopic evaluations of the structure of the talc. The results indicated the talc was similar to that currently being marketed from Montana and probably would have good commercial value.

Jan 1, 1989

By Duane B. Jorgensen

The two calcium sulfate minerals, gypsum and anhydrite, occur in many parts of the world, and gypsum has long been of economic importance in the family of industrial minerals. Gypsum, the dihydrate form of calcium sulfate (CaSO, . 2H20) and anhydrite, the anhydrous form (CaSO,) are frequently found in close association, and it is seldom that a calcium sulfate deposit will consist exclusively of one mineral or the other. Although known gypsum deposits are extensive, anhydrite makes up the larger part of total calcium sulfate resources. Although it has very minor economic use, it is important to the understanding of gypsum deposits and is referred to frequently in the following discussion. Calcium sulfate is one of the principal constituents of evaporite deposits, and when pure, has the following composition: [ ] Deposits of pure gypsum or of pure anhydrite which are large enough to be considered commercial have not yet been found because of both the metastable relationship between the two minerals, and the presence of impurities such as calcium or magnesium carbonates, chlorides, other sulfate minerals, clay minerals, or silica. Most gypsum produced ranges from 80 to 95% pure and beneficiation is normally limited to selective mining or quarrying or upgrading by crushing and screening during mill processing. END USES The largest use for gypsum is based upon the unique property which calcium sulfate has of readily giving up, or taking on, water of crystallization. With the application of a moderate amount of heat in a process known as calcining, gypsum is converted to plaster of paris, the hemihydrate of calcium sulfate (CaSO4 ½ H2O), which when mixed with water will set or harden as the calcium sulfate returns to the stable dihydrate form. This semifinished product, usually called stucco, is then manufactured into a large variety of plasters, wallboard, and block for construction use, or into plasters for industrial applications. About 75% of the gypsum used in the United States is calcined for these purposes. Uses of uncalcined gypsum are principally as a retarder for portland cement, as a soil conditioner, as a mineral filler, and other minor industrial applications. About 25% of the gypsum mined in the United States goes into these markets; however, in other countries with building practices different from those in the United States and Canada, relative usage varies widely. Calcium sulfate deposits are the world's largest sulfur resources; minor quantities of gypsum and anhydrite have been used to produce sulfur or sulfur compounds. This use is accompanied by a unique site-specific set of economics because sulfur is generally available from non-gypsum sources at lower cost.

Jan 1, 1994

By Nathaniel Arbiter

The increasing size of flotation cells as the use of flotation has increased is traced from the first United States application of the process in Montana in 1911 through the following eight decades, using data from the Taggart handbooks (1927) and (1945), from the SME Handbook (1984), and from recent manufacturers' catalogues and other sources for the 1980s and 1990s. With the earliest mechanical cells less than 1 m3 (359) in volume and the largest now available at 200 m3 (7,000ft3), three requirements are necessary: 1) demonstration of advantages in replacing smaller volume by larger volume cells; 2) estimating power requirements, impeller dimensions, and operating rpm by correlation equations; 3) considering effects of using larger cells, in necessarily much shorter rows, on process kinetics. The resulting seven tables that address these problems are presented, and their implications discussed.

Jan 1, 1999