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By C. Newman, N. Schaefer

"INTRODUCTION As underground mining continues to operate at deeper depths and in more complex geologic and geometric conditions, there has been an increased demand for higher design standards in ground control safety and stability within the mining industry. Over the past 20 years, NIOSH has developed, validated, and distributed a number of free software packages (ALPS, ARMPS, AMSS, ARBS, etc.) for the safe design of underground coal mines with respect to ground control. While these programs were initially developed on a, “stand alone model,” where all program data resides on an individual or workgroup computer, modern day web applications have begun to migrate toward a, “multiple-tier model,” allowing multiple users to access an application through an Internet connection. webGroundControl provides users with access to NIOSH ground control design software (ARBS, ALPS, and ARMPS) utilizing a web-based three-tier architecture allowing users to easily access ground control designs, perform on-demand calculations, and provide online collaboration between operational personnel and engineers through a web server. Given advancements in cloud computing as well as the expansion of Internet connectivity on the surface and underground, webGroundControl users will be able to access the applications anywhere (where permissible) at any time. As web-based computing technologies continue to advance and cloud computing gains popularity and momentum, there is an industry need to develop Internet based applications for mine and ground control design (Barczak et al., 2016). The purpose of this paper is to introduce and familiarize those in the mining industry with the basic framework and, more specifically, the user-interface of the webGroundControl application. It is expected that the mining industry will rapidly embrace this new product and webGroundControl will be a new paradigm for mining engineering computer applications. APPLICATION ARCHITECTURE With the advent of cloud computing, web-based applications have become more popular with their adoption of multiple-tier, or n-tier, architecture containing independently operating tiers. The three-tier application architecture utilized in webGroundControl (as outlined in Agioutantis and Newman, 2016) contains a Presentation Tier (Web Server), Logic Tier (Logic/Application Server), and Data Tier (Data Server) as shown in Figure 1. While tiers have the ability to be deployed across and operating on multiple servers, webGroundControl is currently being deployed on a single server located on a university desktop computer. The separation of the application into a series of tiers greatly increases the maintainability and scalability allowing for the adoption of new technologies that can be applied to a single tier without redesigning the software package. The Presentation Tier maintains the user interface translating client requests (through a web server) and displaying results (through a web browser). The Presentation Tier allows for on-demand access from multiple users and compatibility with a variety of personal computers, Smartphones, tablets, etc. on different operating systems. The Presentation Tier has been developed with respect to the HTML and JavaScript languages. Through the utilization of CSS, a coding language which describes the style of an HTML document, the webGroundControl display is able to spontaneously adapt to any browser and any screen. The development of the Presentation Tier will be discussed in more detail in subsequent sections of this paper."

Jan 1, 2017

By Kalman N. Isaacs

Aerial photography is a recognized and integral part of the search for petroleum and for the metallic ores, but its application lags seriously; in the search for the industrial minerals This is, in all probability, a result of the relatively stringent economics of the various industrial mineral industries. The oil and mining companies (particularly the oil companies) can afford generous exploration budgets and thus can experiment with unorthodox approaches such as photogeology. The industrial mineral industry is more restricted, and up to now has relied on less sophisticated methods of exploration. The industrial minerals have been generally defined as those materials extracted from the earth that are neither metals, metallic ores, fuels, nor ground water. Any group chat must be defined in such a negative manner, by citing the things that they do not include, must in themselves be extremely diverse in character. This is truly the case for the industrial minerals; the full list of industrial minerals is incredibly long and tends to increase year by year.

Jan 1, 1964

By Keith G. Wallace

Coal mine ventilation systems are often subject to high leakage rates. As a result, changes in airflow resistance will strongly affect the efficiency with which air is delivered to the working place. One major source of airflow resistance is the line brattice used to direct air from the last open crosscut to the working face. Because it is a great distance from the fan, the resistance of the line brattice can result in more overall leakage than an equivalent resistance closer to the fan. Substituting auxiliary fans for brattice eliminates this source of resistance, with improvements in system efficiency and cost. Also, in some mines, the leakage that leads to spontaneous combustion can be reduced. The benefits obtained by several different brattice and fan substitutions have been studied by Mine Ventilation Services, Inc., under contract to the Bureau of Mines. Changes in main fan duty were compared with additional costs associated with auxiliary fans. Results indicate that in some circumstances, considerable leakage reductions and cost savings are possible.

Jan 1, 1986

By Trevor R. Ellis

In August 2011, the Southern African Institute of Mining and Metallurgy (SAIMM) contacted mining institutes and related societies internationally to assess their interest in participating in coordination of the review of the South African Code for Mineral Valuation (SAMVAL) with reviews of other mineral valuation standards. The main mineral valuation standards are the CIMVal Standard of The Canadian Institute of Mining, Metallurgy and Petroleum (CIM), the VALMIN Code of The Australasian Institute of Mining and Metallurgy (AusIMM), the SAMVAL Code, and the extractive industries? guidance note of the International Valuation Standards Council (IVSC), Valuation of Properties in the Extractive Industries, GN 14, designed for application within the full set of International Valuation Standards (IVSs). By January 2012, SAIMM had concluded that the level of respondent interest was adequate to organize a meeting. A meeting was scheduled for April 18, 2012 in Brisbane, Australia in conjunction with a VALMIN mineral valuation conference organized by the AusIMM. The stated purpose of the meeting was to develop an accord on terms of reference for pursuing harmonization of mineral asset valuation standards adopted by the participating mineral institutes. SME decided that, although it has not developed its own mineral valuation standard, it should participate in the Brisbane meeting and the harmonization process, as also did the American Institute of Minerals Appraisers (AIMA).

Jan 1, 2012

By J. S. Long

A finite-difference model using a digital computer was constructed to assist in the water management of a proposed oil-shale mining operation in the Piceance Basin in Colorado. The presence of ground water is both a detriment and a benefit for development of the resource. On one hand, dewatering is required because permeable zones are present in and above the oil-shale sequence, and rich oil shale at the proposed mine is as much as 457 m (1500 ft) below the water table. On the other hand, ground water is the most feasible source of water for processing the oil shale. A ground- water model was constructed to simulate the development of an environmentally acceptable water-management system that will satisfy both the mine-dewatering requirements and the water-supply requirements for processing. The ground-water model discussed in this chapter was constructed for the Rio Blanco Oil Shale Co. (RBOSC) by International Engineering Co., Inc., a subsidiary of Morrison-Knudsen Co. The model was applied to evaluate dewatering and water control systems for several open-pit mining plans initially investigated to develop Federal Lease Tract C-a. A collateral application of the model analyses was to project effects of the proposed dewatering operation on the regional ground-water regime in connection with a permit acquisition program by RBOSC. Subsequently, RBOSC has completely changed its mine development plan and has adopted modeling and related techniques more suitable for study of that plan and dewatering operation. The authors of this chapter are solely responsible for the contents and conclusions.

Jan 1, 1979

By Harry R. Dahlberg

Heap leaching is discussed as a unit process. Five factors are identified as the principal elements that can be measured and/or controlled. These are: 1. Material Size 2. Volume of solution 3. Tonnage of heap 4. Time 5. Solution concentretion. The Rate of Extraction Curves obtained from an actual heap or column tests describes the economic viability of the unit process. By analysis of these curves and the five factors end their inter-relationship it is possible to determine how the extraction rate can be increased. The practice of leach and rest used by many operators is analyzed and shown on a hypothetical rate of extraction curve. The influence of the driving force of the hydrogen ion and ferric Lon as Lixivants and its effect on the rate of extraction curve is discussed.

Jan 1, 1979

By Ernst P. Hall

As a scientist and an engineer whose responsibilities include the consideration of air pollution and its control, I am frequently called upon to answer variations of two basic questions, These questions may I be set forth as: (1) How much air pollution does the coal industry cause? (2) How serious is the air pollution problem to the coal industry? At first these questions may seem elementary and almost trite, but serious consideration of them will show that they are technologically involved and I further complicated by the subjective base to which they must be evaluated.

Jan 1, 1963

By A. Bascetin, A. Nieto

One of the most difficult problems in mining operation is how to determine optimum cutoff grades of ores at different periods over the lifespan of the mine that will maximize the net present value (NPV) of the mine. Cutoff grade optimization maximizes the NPV of a project subject to capacity constraints in the mine, mill and the market.. This paper describes the determination of a cutoff grade strategy based on K. Lane’s algorithm adding an iterative optimization factor calculated for every year during the live of the mine to maximize the project’s NPV. The introduced algorithm is a windows based program developed at Virginia Tech which coded in visual-basic within a spreadsheet environment (Excel). The resulting cut-off windows based program is a user-friendly tool which calculates interactively different mining cutoff grade scenarios. The benefits of the methodology are demonstrated using a hypothetical case study. The authors have observed an improvement of the total NPV using this iterative approach using a year by year optimization factor.

Jan 1, 2007

By F. J. Susko

The U.S. Bureau of Mines is using Fourier-transform infrared (FT-IR) analysis to investigate the bonding mechanism which occurs during the dewatering of clay slurries. High molecular weight polymers are used as flocculating agents in these processes. This investigation presents the results of an FT-IR study of calcium-exchanged montmorillonite treated with polyacrylamide (PAM) and polyethylene oxide (PEO). Both thin film and attenuated total reflectance (ATR) spectroscopic techniques were employed to study this clay-polymer system~ Results suggest PAM is adsorbed to the clay via the nitrogen atom of the polymer. A water bridge is involved in the bonding between the clay and PE~. Evidence also suggests that PEO may be adsorbed directly onto the surface of the clay.

Jan 1, 1990

By R. W. Smith, D. L. Taylor, K. A. Altman

The importance of metallurgical information in reaching appropriate decisions during the development of mining projects is demonstrated. A financial analysis is calculated using discrete system simulation. The results are compared to the results of a traditional sensitivity analysis. The traditional analysis is shown to have the potential to overestimate the value of mining projects. The type of statistical distribution used in a random number generator affects the results significantly. The statistical method of analysis provides insight into the amount of metallurgical testing needed and provides verification of how representative the samples are.

Jan 1, 2002

By Wendell R. Peters

Shallow underground voids resulting from early coal mining and other resource recovery activities over the past several decades are now being recognized as a significant cause of ground subsidence problems. Uncertain knowledge of abandoned coal mines also imposes potential hazards in current mining operations since water inundation or the release of methane gas is a serious hazard when mine excavation operations break into an abandoned mine. Requirements for detecting and mapping subversive man-made tunnels in previous work has led to the development of a surface- operated automatic earth resistivity survey system and associated computer data processing system for military applications. Field demonstration tests of this system have resulted in successful detection of tunnels at depth-to- diameter ratios greater than ten to one. Under the sponsorship of the Bureau of Mines, a similar high-resolution earth resistivity system was designed and constructed for use as a potential means of detecting coal mine workings. The hardware and software aspects of the new system are described together with applications of the method to the survey and mapping of abandoned coal mine workings. Field tests are presented showing the detection of both air-filled and water-filled mine workings.

Jan 1, 1981

By L. Xiao

Using K-oleate as a collector and alizarin red S (ARS) as a modifying agent, selective depression of dolomite from francolite was achieved in alkaline medium (pH> 9.0). Interestingly. ARS was also found to depress igneous apatite in alkaline medium in oleate flotation of apatite and calcite. Adsorption of ARS alone on dolomite was found to be higher than that on francolite. Complimentary adsorption experiments of ARS and K-oleate showed that oleate adsorption was increased in the presence of ARS on francolite but not on dolomite. K-oleate adsorbs on both francolite and dolomite and causes precipitation of calcium and magnesium oleate. Such precipitates can be pre-vented when ARS is present. The results are explained in terms of competitive adsorption for the active sites on francolite and dolomite by oleate and ARS, and their interactions with dis-solved mineral species in solution.

Jan 1, 1988

By Robert W. Holliday

Natural resources are the reservoir from which society draws its material sustenance. Although there is a growing awareness of the need for aesthetic resources such as space for recreation and natural beauty, the basic resources are soil, air, water, and minerals including fuel. Minera's and all sources of energy gain in relative importance with advancing technology and expanding industrilization. In the highly industrialized economy of the United States, almost every aspect of man's life is touched in some way by a product of, the mineral; industries. Agriculture owes much of its productivity to mineral-based fertilizers, insecticides, and mechanical equipment. Modern construction, manufacturing, communications, and transportation are all dependent on nonmetallic minerals, metals, and fuels. Throughout history, those nations with access to minerals, and the technology for using them, have gained ascendency. Before World War II the leading powers also were, leading coal producers. In order of declining rank the five leading' coal producers were the United States, the United Kingdom, Germany, the USSR, and Japan. That the military victory went to the side with the greater' capacity to convert iron and coal into tools of industry, and weapons, is' more than coincidence. It is a fundamental' fact of existence. It is axiomatic that the United States must have a continually increasing supply of minerals if we are to meet the needs of our burgeoning population for a comfortable standard of living and for national security.

Jan 1, 1968

By J. Douglas

The past year has been a strange one for the fertilizer industry of the world and the United States. Listening to news stories, you would think the sky is falling on the world's agriculture and probably conclude that we should have had an exceptionally poor fertilizer season. In some respects, we did. Prices were low, profits were low, and in some cases nonexistent, but volume was good. We heard much in the press about the farmers' credit crunch. The truth of the matter is that only 6.6 percent of the U.S. farmers have debt-equity ratios of 70 percent or more, and a large percentage of our farmers have absolutely no debt but operate entirely on their own cash assets.

Jan 1, 1985

By Daniel R. Walton

This paper covers several points of interest to mine engineers and planners involved in evaluating or conducting geostatistical coal reserve estimates. In particular, the ability to optimize borehole drilling locations and minimize drilling costs is addressed. Also discussed is the concept of confidence intervals for estimated coal characteristics obtained through geostatistical estimates and their importance in decision-making for mine planners. Finally, a discussion is presented on how geostatistics enables identification of invalid data points and actually forces strict attention to data editing and proper geologic interpretation.

Jan 1, 1982

By E. Craig Simmons

Uranium is an element incompatible with respect to the major rock-forming minerals crystallizing from granitic magma, entering in- stead trace minerals such as zircon. The relationship between the saturation limit (SL) for such a mineral and the bulk distribution coefficient (Do) for U is central to understanding the distribution of U and its availability to late- stage fluids which can form ore deposits directly, or labile U which can be remobilized later. Low SL values imply early crystallization of zircon, but in very small proportions, minimizing Do and maximizing the degree of enrichment of U in late-stage fluids. Thus, granitic rocks with low Zr contents (due to a low saturation limit for zircon) are most likely to evolve U- enriched differentiates; this will be reflected in a high U content of the zircons (but not necessarily high U abundances in whole-rocks). Thus, the ratio of the U content of zircon to the Zr content of the corresponding whole-rock is potentially a very useful parameter in identifying granitic rocks which are most likely to have U-enriched solutions associated with them. The granitic rocks associated with the U deposits of the Midnite Mine area, Washington, have geochemical characteristics which fit very well the model presented here. The rocks are very low in Zr (100 ppm) and contain zircons with extremely high U contents (3,000-4,000 ppm).

Jan 1, 1981

By Catherine C. Kilgore

The Bureau of Mines investigated the availability of fluorspar from 35 domestic and 50 foreign, mines and deposits in 13 countries. Only 6 domestic properties are considered to be economic reserves, as 29 domestic deposits were found to have an average total cost of production that was uneconomical at a breakeven (0 pct) DCFROR. The 50 foreign properties evaluated were selected to represent at least 85 pct of the known demonstrated fluorspar resources located in market economy countries and China. All evaluated foreign operations were found to be economic to marginally economic in January 1984 dollars. World demonstrated ore reserves of 344 million metric tons (mt) containing 123 million mt of CaF2 were evaluated for the 56 operations. Average total costs needed to cover all costs over the life of each operation were determined for all recoverable fluorspar products. Comparisons of mining, beneficiation, and transportation costs per mt of fluorspar concentrate illustrate advantages between countries. Of the three largest producing countries, China, with its high-grade, low-cost operations had the lowest weighted average total cost of production ($38/mt concentrate). Mexico was next at $54/mt concentrate, and South Africa needed an average of $90/mt of concentrate to cover all costs of production for its low grade deposits.

Jan 1, 1985

By S. K. Kawatra, A. K. Bakshi

An on-line rheometer was developed to monitor the slurry rheology of a thickener underflow. The thickener processed a chalcopyrite flotation concentrate having a top particle size of 125 µm and a solids content of 30% to 60% (by weight). The slurry also contained residual flotation reagents, resulting in hydrophobic particles. Polymeric flocculants and lime were added to the thickener to flocculate the particles. Using the on-line rheometer, the slurry was found to exhibit pseudoplastic behavior with no yield value. It was also determined that factors other than the percent solids were responsible for changes in the slurry rheology.

Jan 1, 1999

From some of the largest tunnel projects in the some of the most vibrant cities, to smaller projects in remote corners of the globe, the Robbins Co. announced two tunneling projects in which its tunnel boring machines will be used. Robbins earth pressure balance (EPB) machines undercut Downtown Zhengzhou. Zhengzhou, a city of 7 million people, is set to become a crossroads for rail commerce in China. The country?s future main routes, traveling between Beijing and Guangzhou (North-South), and between Xuzhou and Lanzhou (East-West), will intersect in the city. The plan includes up to four rail lines in Zhengzhou itself, which will eventually link up to the national lines. Excavation of Zhengzhou Metro?s new Line 1 tunnels began on Sept. 28, 2010, when the first of two 6.3-m (20.7-ft) diameter Robbins earth pressure balance (EPB) machines was launched from a 16-m- (52-ft-) deep shaft.

Jan 1, 2010

By R. Hagemeyer

In North America, the paper industry is by far the largest consumer of coating and filler mineral pigments. Present use is at an annual rate of 5.5 million metric tons with a value of $660 million. Current estimates are 65 percent is used in coating and 35 percent in filler applications. During the past decade, the switch to alkaline papermaking has provided the opportunity to substantially increase filler levels while maintaining paper strength. As a result filler consumption has been growing at a late in excess of 15 percent yearly. Unfortunately, within a few years, mandated recycling could slow or even reverse this trend. The critical issue is finding an economically viable method for recycling the mineral pigment and/or minimizing the disposal problem

Jan 1, 1994