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By S. D. Bearden

The world's reserve base is adequate for at least 100 years at the current consumption rate. China, India, and the U.S. are expected to remain the leading producing countries. The U.S. will continue to be the largest consumer of the production. None of the known substitutes for barium sulfate are expected to impact existing applications. World production in 1995 was 4,410Mt. This is about 50% of the projected capacity. Consumption is directly proportional to hydro-carbon well installation activity. Imports are expected to continue to supply more than half of the U.S. requirements.

Jan 1, 1997

By C. W. Hunt

I wish to register strong disagreement with the choices of drilling sites chosen by the Continental Scientific Drilling Committee, while endorsing the stated objectives. Of special significance is the lack of any site involving the metals most needed today in the US, while 9 to 13 km of drilling are allocated to gold and silver districts and 11 to 17 km to base metal (mainly copper) districts. Why is nothing proposed for platinum group or chromite? Is this because the committee did not know of such a site? If so, I offer such a site in California (see Fig. 1). The mineralization shown in Table 1 occurs in a large peridotite body in western Tehama County, CA. Petrography has demonstrated unequivocal evidence of migrated PGE deposited in peridotite and chromite of hypabyssal nature. Active diapirism (due probably to serpentine buoyancy) above a reactivated mantle to surface conduit marks the position of the conduit. Young explosion breccia cemented loosely by volcanic glass and tuff demonstrates the significance of the conduit as the prime source of the various emissions. Deep drilling could result in major metals discoveries as well as shedding light on the grand questions of platinum group mineralization. What role water has played in this occurrence is not yet certain; but chlorine and asphaltite have been detected in and adjacent to native PGM, suggesting a major role for water. The explosion breccia suggests that this excellent site could overlie entrapped geothermal steam.

Jan 1, 1988

By Malcolm D. Flavel

Recent research into the mechanisms of crushing processes has led to the establishment of new criteria for the effective design and operation of comminution plants. This paper reviews this work and gives examples of the productivity gains and cost benefits that have been achieved in the practical application of these findings.

Jan 1, 1988

By Michael Forbes, Rick Jeuken

The challenge of managing geological uncertainty in mine planning is central to optimizing resource extraction while minimizing risks and costs. This paper introduces a novel approach to coal mine planning by integrating chance-constrained programming to address the uncertainty inherent in mining operations. The main takeaway from this work is the demonstration that focusing on reducing the variance of high-quality coal blocks, rather than low-quality ones, can lead to better blending outcomes, higher profitability and more efficient resource utilization. The study presents a case study of a coal mining operation, using chance-constrained programming to manage the uncertainty surrounding coal property predictions, specifically the predicted coke strength after reaction (CSR).

Jan 1, 2025

By Kef ton H. Teague

This paper will discuss bentonite deposits in Texas, Oklahoma, Louisiana, Mississippi and Alabama. The discussion will be re¬stricted to a review of the so-called calcium or non-swelling bentonites. In other words the exchangeable cation is calcium. The term "bentonite" is used to describe a clay material, composed essentially of the clay mineral montmorillonite. In addition, bentonites may contain various impurities such as glass shards, feldspar, quartz, muscovite and biotite mica, glauconite, pyrite, hydrated iron oxide, gypsum, organic material, etc, Most of the southern calcium bentonites contain at least 70% montmorillonite, Bentonite as mined may range in color from dark grayish greens through various shades of grays, reds, yellows and browns to nearly white. It is normally massive and breaks with a conchoidal fracture. When air dried, closely spaced shrinkage fractures occur. Moist bentonite has a soapy feel, with little or no obvious "grit". Bentonite deposits were first discovered in Mississippi about 1925, in southern Monroe County. During the thirties and early 1940's, deposits were identified in Alabama, Texas, Oklahoma, and Louisiana. Perhaps the earliest production of southern bentonite was from a deposit in the valley of the Tombigdee River, south of Jackson, Alabama in 1936. Production commenced in Mississippi during the latter part of 1938 at Pontotoc. The growth and development of the bentonite industry in the southern United States owes its beginning to three events. The first of these was the discovery by German researchers,

Jan 1, 1972

By Russell L. Dahl

In a continuing effort to improve plant efficiency, United States Steel's Atlantic City Ore Operations completed the rubber lining of its balling drums in late 1982. This resulted in benefits of reduced bentonite consumption, reduced maintenance costs, improved production rates, and lower power consumption. These advantages far outweigh the disadvantages of increased oversize production and increased surging on the roll screen sizing devices. Certain operating characteristics and variables are discussed herein.

Jan 1, 1983

By Juan C. Diaz, Juan P. Carmona, Manuel Z. Salgado, Oscar J. Restrepo

The “Teaching Kids” project is an educational initiative for young people and children from elementary schools. It is carried out by Mining, Geological, and Environmental Engineering students from the SME Student Chapter of the Universidad Nacional de Colombia, Medellin. The primary purpose of the Teaching Kids project is to share knowledge about geosciences and mineral resources in a didactic and attractive way, emphasizing the importance of identifying the use of minerals in daily life and responsible and sustainable mining in our society. Furthermore, this project aims to promote the importance of pursuing geoscience majors in the new generations and improve the mining industry’s public perception. Different methodologies related to early childhood education are implemented, such as gamification, in which the dynamics of games are adapted during the development of workshops to teach and learn in an active and motivated environment. Furthermore, the Montessori Method is used. It implements textbooks, sensory mineral boxes, and presentations to allow learning through experimentation itself (Montessori 2003). The implementation of this methodology has been successful; it has shown high engagement, participation, and retention of the basic concept of geoscience and mining.

Feb 1, 2025

By Mustafa Kumral, Mehmet Balci

Strategic mine planning focuses on cutoff grade selection, capacity planning and block sequencing. Despite significant knowledge accumulated, potential value can be added to mineral sourcing by addressing various aspects. A case study on a metallic deposit with a lognormal grade distribution examines if grade/metal distribution influences cutoff grade selection. Six data sets with different shape and scale factors, but the same ore tonnage and metal quantity, are analyzed. Results indicate deposits with lower shape and scale factors are more sensitive to metal price and discount rate changes. The study also investigates the effect of economies of scale (EoS) on project value, focusing on the ratio of variable cost to total cost (capacity factor). Two regression analyses are conducted for optimal capacity planning and cutoff grade selection. The first shows capacity planning is highly sensitive to the EoS of mining and mineral-processing costs, with grade variability and metal distribution being negligible. In the second analysis, grade variability and EoS of mineral processing costs are vital for cutoff grade selection.

Sep 1, 2024

By Fouad Faraj

For every blast pattern, zones of unique material types need to be classified before mining. Most material types can be summarized into different kinds of ore and waste. Blocks generated from blasthole assays are too small to be selectively mined, so areas with a single material classification meeting the mine’s selective mining unit must be defined. Current industry standard practices are to manually draw ore/waste dig limits, but this process is subjective and results in quantities of dilution and ore loss that can be improved upon to enhance the profitability of mining operations. In this study, two weeks of production data from a homogeneous copper (Cu) porphyry and heterogeneous manto-type Cu deposit were used to assess the variability in the hand-drawn dig limits of 20 geologists, mining engineers and ore control specialists, which were compared with the optimal ore/waste delineation. The profit for 20 distinct hand-drawn dig limits for the homogeneous mine varied by 3.7 percent, from $10.5 million to $10.9 million, averaging at $10.8 million. The percentage was nearly double for the more heterogeneous mine at 5.9 percent, from $17.9 million to $19.0 million, averaging at $18.6 million. Using the optimal ore waste delineation, the profit increased to $11.0 million (1.9 percent increase) and $19.3 million (7.0 percent increase) for the homogeneous and heterogeneous deposit, respectively. The natural variability, diggability requirement and selectivity are identified as the main drivers of ore loss and dilution. Recommendations are provided for reducing the subjectivity in manual hand-drawn dig limits by integrating dig limit optimization algorithms as a tool to assist practitioners.

Oct 1, 2024

By R. Fields

Nevada is primarily known today for its nation-leading production of gold and silver. However, industrial mineral production continues to play an important role in providing construction materials to help make the state the fastest growing in the United States. Aggregate production in Nevada was about 20 million tons in 1991. Most of that was used in construction in the fast-growing Las Vegas area. The state leads the nation in the production of barite and mined magnesite and has significant production of lithium carbonate, diatomite and gypsum. Other industrial minerals produced in the state include specialty clays, silica, lime and dolomite and relatively small production in salt, perlite and dimension stone. Industrial minerals operations are subject to state and federal permitting requirements, especially in the areas of air and water quality and mined land reclamation. As in all segments of the mineral producing industries throughout the nation, the amount and complexity of regulations affecting industrial minerals has increased significantly in recent years. Nevada is no exception.

Jan 1, 1993

By J. Gonzales

For this paper, blending is conceived as a linear process that takes a proportion from one stockpile or location and mixes it with another proportion from another stockpile or location, with the aim of obtaining a set of attributes in the final combination that satisfies a given quality standard. A blending class is the combination of ore attributes and grade limits that should be stockpiled in order to achieve the target quality for the process Plant. Current literature considers the number of blending classes in the Open Pit Scheduling Problem as fixed; however, this paper shows how to define specific blending classes for a given deposit so that the schedule can be solved with Sequential Linear Programming. Finally, a practical application in a Peruvian copper mine is shown, involving four ore attributes: alteration code, arsenic, oxide content and copper grade. INTRODUCTION In copper ore deposits, blending for quality has not been a typical issue as it was for coal and iron ore; however, current copper deposits in the world are becoming geologically and chemically more complex than in the past and is not uncommon to have quality standards involving up to four attributes, introducing an additional complexity to the mine scheduling process [1]. In order to solve the Open Pit Scheduling Problem with multiple ore quality constraints, two assumptions are necessary [2]: - Grade constraints are defined only by specifying an upper and lower limit; - Ore attributes in stockpiles are pre-determined, i.e., the upper and/or lower grade limits defining each stockpile are already known at the time of setting the schedule. Assuming each ore attribute is classified as high, medium or low, and there are four attributes to be controlled in the target ore quality, the number of possible blending classes would be 3^4 = 81. This number is impractical to manage in Operations, and increases the complexity at the time of running the schedule; therefore, a more efficient way of classifying ore is required. Note that in practice, one blending class can be split into more than one stockpile location due to physical capacity constraints. Therefore, the number of stockpiles could even be more than 81. BLENDING CLASSES DETERMINATION For a given set of ore grades with lower and upper limits to be achieved, one has to find all feasible ore classes such that when blended, their grades will lie within those limits.

Jan 1, 2019

By Alan C. Richter

Introduction The East-West Gateway Coordinating Council is an organization of local governments formed in 1965 to identify regional problems and to formulate policies, plans and programs to resolve them. The major goal of the Gateway Council is to improve the quality of life for the citizens of the St. Louis Region. While East-West Gateway Coordinating Council is the organization I represent and it only deals with the St. Louis Metropolitan Area, you will find one or more similar organizations in each of our nation's urbanized areas. As a result, for illustrative purposes, I will use my organization to portray what is happening nationwide. For example, in order to eliminate duplication, the Council reviews local applications for approximately 100 federally funded programs in such areas as highways, mass transit, parks, water treatment, and sewers before they can be sent to the appropriate funding agency. The Council's varied functions place it in a unique position of receiving more and more responsibility for developing strategies of implementation of various environmental regulations. This is due to the fact that environmental control is a relatively new field and we, as a country, are relatively inexperienced. The resulting regulations and guidelines will depend, to a great extent, on what the general public is willing to accept in terms of controls and what price they are willing to pay in terms of taxes and increased costs. Land Use: Growth vs No Growth This is perhaps the most encompassing environmental issue. We, as a nation, are beginning to realize that land is a limited natural resource and that the way we choose to use 'this resource affects many other aspects of our lives--whether we can catch edible fish in the Mississippi, how much we pay for sewer services, if we can swim in a

Jan 1, 1977

By H. M. Ray

The discovery of the New Lead Belt in the mid-'50s began a search for mill design criteria that is continuously updated. The opportunity to design, construct, and operate four new mills in the span of 20 years provided fertile areas for new concepts. The central theme for design parameters encompassed simplicity, functional, and economic consideration. Ore characteristics for each plant remained relatively constant, providing stable criteria for grinding circuits. Bond index nominally 10-12. Flotation circuit parameters were based upon power application with 10-20% excess capacity built-in to protect recovery. Newer equipment exhibits greater power application efficiency lowering horsepower requirements per ton. Instrumentation was installed to stabilize circuits, protect equipment, and improve products. With ever increasing requirements of higher quality products, environmental considerations, and operating cost pressures, the upgrading of operating procedures is in a constant state of flux. Installation of more efficient equipment, chemical processing, or any other technique would be considered as feasible. Current practice is for St. Joe to design and engineer in-house its own plant design. The exception being detailing of structural steel. It is felt that familiarity with past design criteria serves as a valuable foundation to incorporate changes. Also, direct contact with operator provides specific data, and feedback for constructive criticism that is utilized for defining and correcting problems. The results are in reality an operator's plant with the benefit of advancing technology that meets the demands for improved products without sacrificing the economies of throughput or recovery.

Jan 1, 1977

By J. Juilland

Over 10 percent of the United States of America or 41 percent of the Federal lands is managed by the Bureau of Land Management (BLM) as Public Lands. The mission is to manage the use of these lands and their resources. The way in which BLM carries out its mission is being refocused under the concepts of biodiversity and ecosystem-based management for the benefit of various human needs including environmental, social and economic values. The Bureau is developing methods to integrate the renewable and non-renewable resources programs into the concepts of biodiversity and ecosystem-based management. Exploration, development and extraction of energy or mineral resources on Public Lands are affected. The statements that following the next few pages are my personal views as a scientist (economic geologist -mining technologist) who is and has been involved for the last twenty years in the multiple-use management of Public Lands. They are not necessarily the position of the Bureau of Land Management, although much of the information on which I base my views comes from my experience with the BLM. The Bureau of Land Management (BLM) manages over 10 percent of the United States (270 million acres or 108 million hectares) which is 41 percent of the Federal Lands. Lands managed by BLM are known as Public Lands as opposed to the National Forest Lands which are Federal Land Policy and Management Act (FLPMA) of 1976 which in Sec. 102 states ??that it is the policy of the United States (7) ?that management be on the basis of multiple use and sustained yield??, the mission of the BLM is rapidly refocused under the concepts of biodiversity, ecosystems, and ecosystems-based management for the benefit of the environment, human needs and socio-economic values.

Jan 1, 1994

By Nick Karlin

Dragados USA is constructing the LA Effluent Outfall Tunnel, a 7-mile, 18 ft internal diameter effluent discharge tunnel, utilizing a 21.6 ft (6.585 m) Herrenknecht Mixshield TBM. This paper highlights the means and methods used for TBM launch from a 55 ft diameter shaft excavated in wet with diaphragm wall support of excavation. This included SEM excavation of jet grout blocks for starter and tail tunnels, temporary concrete structures and steel installations, TBM sealing system, umbilical management for TBM hydraulic, electric and bentonite circuits as well as complex segment delivery logistics. The many launching challenges were overcome thanks to the innovative approaches from the project team.

Jun 13, 2023

By Anna Eleria, Joseph Welna, Jim Herber, Nathan Campeau

Constructed by stonemasons over 120 years ago, a portion of the Trout Brook Storm Sewer Interceptor (TBI) owned and operated by the Capitol Region Watershed District in Saint Paul, Minnesota, needed rehabilitation. A routine inspection of the 10-foot limestone block tunnel revealed degraded and missing mortar between the blocks, allowing significant infiltration and soil migration through the tunnel joints. Conditions, including damaged and missing blocks, were considerably worse in a 250-foot-long segment beneath a busy mainline railroad corridor. Barr’s solution included tuck-pointing to repair the mortar joints, shotcrete overlay, and construction of a hybrid cast-in-place/shotcrete “tunnel within a tunnel” to support the mainline railroad loads.

Jun 13, 2021

By Liz Diaz, Tacio Ferreira

Capstone Copper’s Pinto Valley Mine faced challenges in recovering rock and ore on final walls because of geotechnical constraints that require restrictions on methods for loading blastholes adjacent to the pit boundaries to preserve wall stability. The operation had been using the same drill and blast designs for years. With changing geology, such as harder rock, as mining progressed, material was being left unmined in final walls because of poor breakage. The amount of unrecovered, unprocessed ore was estimated at approximately 380,000 tons a year generated from an average of 60 final wall blasts performed annually. The engineering team from Capstone and Dyno Nobel engaged to minimize the amount of material left on the final pit walls. This paper presents how we collected data, reviewed design standards, and found opportunities to improve ore recovery from pit final walls without increasing drilling and blasting costs. The results collected from implementing the new design on two benches showed the potential for extra revenue of approximately $3.6 million generated annually from reducing final wall unrecoverable underbreak by nearly 71% on the mine’s highwalls.

Feb 1, 2025

By R. M. White

Abstract. Gulf Coast Salt Domes are being considered for radioactive waste disposal and this paper describes the geophysical techniques currently being used and those being considered for later phases of the program. Detailed gravity work utilizing a modification of the Talwani-Ewing modeling technique, shallow high resolution reflection seismic surveys using the mini-sosie concept, surface electrical resistivity and down-hole geophysical logging to add a third dimension to all of the surface techniques and to allow inverse modeling of the surface data sets are being utilized. The logic of the combined geophysical surveys will be discussed as well as their relative economics and their relationship to the overall exploration effort.

Jan 1, 1980

By M. Solomon

Crushers are designed and manufactured to survive the severe duty of mining environments worldwide. Under these conditions the crusher performance and availability is one of the critical factors in the mine?s production and profitability. Traditionally the development of these machines tends to be experience-based, incremental improvements in design due to challenges of different applications, duty, or manufacturing. In order to better serve the mining industry a new approach was taken to the design of primary crushers. This approach was to focus on safety and maintenance activities. The result of this effort is a new generation of gyratory crushers that can be serviced from above. Using the features of this new generation of crushers to their fullest extent crushing installations have improved safety, reduced design and construction costs, and lowered maintenance requirements. This presentation explores the benefits of two crusher installations utilizing top service crushers.

Jan 1, 2010

By Cliff Holloway

The past year has been difficult for Canada's primary industries. The mining, oil and forestry industries have been hit by low prices and a reduced demand for natural resources. Foreign competition, militant environmentalists, the breakdown of the Asian and European economies and Canada's shrinking dollar have all put additional pressures on the commodity purchaser to buy smarter. It is easy to appreciate why operations and maintenance supervisors want the best performing product. It makes good sense. The challenge is to source that quality product while staying within the budget. The bottom line (price), however, often becomes the control- ling factor, usually at the expense of quality and performance. This is short-term thinking, often with expensive consequences.

Jan 1, 1999