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By Nathaniel Wollman

About nine years ago the President's Materials Policy Co commission under the chairmanship of William Paley released its report entitled "Resources for Freedom." Not long ago the Senate Select Committee on National Water Resources under the chairmanship of Senator Kerr released a study entitled Water Supply and Demand. Both reports contained projections of future water user the report for 1975, and the Select Committee print for 1980 and 2000, It is my task to compare the two reports. In the initial letter from Mr. Kazmann arranging for thus session he suggested that I present "a critical evaluation of the Paley Report's section on water ?ten years later,? which might include a comparison of predicted and actual water-use rates and would spotlight the assumptions which lead to errors in the predictions , . ." It is possible to compare the results of both studies, and it possible to explain art of the differences that can be found between them. The remainder must remain shrouded in doubt, since the Paley Report did not give all details of the methods used in estimating the com¬ponents of water use.

Jan 1, 1961

By S. J. Swan

A computerized on-line process control system designed to monitor and control the seven-cone copper precipitation operations at Kennecott Copper Corporation's Chino Mines Division in New Mexico has been continuously operating since April, 1972. The cone monitoring system consists of plant sampling components, process measurement instrumentation, on-stream X-ray spectrometer, control computer, typewriters for programming and for operating reports, foreman's communication console, and cone automation hardware. The system provides the following functions: (1) assays for copper and iron from ten process streams on a continuous rotating basis, (2) directs hardware to automatically flush and start up cone units based on measured performance variables, (3) provides continuous plant operating data and calculates metallurgical averages as well as production figures for shift and daily summaries, and (4) provides data logging capabilities. The system is very reliable and improves plant performance by increasing yields, reducing scrap iron consumption, and reducing operating manpower requirements.

Jan 1, 1975

By James A. Decker

Hanna has developed three production planning systems to help the mine engineers determine the sequence of mining from available ore supples. The Production Scheduling System was developed to give the staff a tool for long range planning by sequencing the removal of blocks from an open pit property. It was needed to determine the year of removal for each block so that the optimum present-valued pit limits could be established by our pit design program. Since in this type of planning short term grade control is less of a factor than it is in daily or monthly planning, the system gives the program greater control and more latitude in block selection. It permits only full blocks to be taken.

Jan 1, 1984

By William F. Lawrence

Research performed by the West Virginia University Coal Research Bureau under the sponsorship of the U. S. Bureau of Mines has demonstrated that coal-ash can be converted into mineral wool insulation of a quality equal to commercial grade mineral wool. An unexpected benefit has been gained due to the discovery that the usual and costly fluxing agents employed when using conventional raw materials are not required when producing mineral wool from coal-ash. Because coal-ash sources are commonly located close to mineral wool marketing areas and because mineral wool is seldom shipped far as a result of its low weight and high volume, the use of coal-ash may offer the mineral wool producing industry profitable opportunities. Moreover, coal-ash produced from experimental limestone based air pollution control processes also yields high quality mineral wool which may aid in retarding corrosion of metals contacted by the wool. In addition, internal fluxing effects and possible sulfur oxide utilization could provide economic advantages to the use of these "modified" ashes.

Jan 1, 1969

By Ivan V. Klumpar

If components of a gas-liquid stream react with each other and with stationary solids, involving parallel and sequential, reversible and irreversible, and slow and instantaneous reactions, the process can be defined by a set of simultaneous differential rate equations and simulated as multistage semibatch re¬actors. Each stage is divided into finite time increments. Within each increment, even the simultaneous reactions are treated as sequential. The proposed method follows process evolution from non-steady state startup to normal operating conditions. It allows computing byproduct buildup in recycles, tracer response curves and, in case of underground processes, expansion to adjacent parts of the deposit.

Jan 1, 1979

By Edward S. Plotkin, Joseph D. Guertin

In a continuing effort to upgrade tunnel design and construction practice, the New York City Transit Authority sponsored a geotechnical monitoring program on a recently completed section of the E. 63rd Street line in mid-town Manhattan. The purpose of the program was to document rock behavior as well as temporary and final rock support systems to provide a possible basis for either confirmation or modificification to design methods and construction specifications. This paper describes those portions of the study associated with rock behavior and temporary support systems. The entire study included monitoring of rock movements above the tunnel as well as adjacent to a 36.6m (120 ft) shaft, monitoring of stresses in steel ribs, monitoring of loads in rock bolts in two test sections and monitoring of stresses in the final concrete lining. PROJECT DESCRIPTION Route 131-A, Section 4 is located in mid-town Manhattan extending from under the Central-Park Zoo on Fifth Avenue eastward under 63rd Street to the end of contract between Madison and Park Avenue. Figure 1 is a Project Locus Map. The contract included approximately 355m (1165 l.f.) of 4 track tunnel(13.4m (44 ft) wide by 13.7m (45 ft) high excavated dimensions) plus a 22.9m (75 ft) by 19.8m (65 ft) by 36.6m (120 ft) deep ventilation shaft. The entire tunnel and most of the excavation shaft was excavated in metamorphic rock, known locally as the Manhattan Schist. The depth to tunnel invert varied from approximately 27.4m (90 ft) at the west end of the contract to 35.Om (115 ft) at the east end. Rock cover above the excavated crown varied from approximately 6.7m (22 ft) at the approximate mid-point of the contract to 18.9m (62 ft) at the western end. A plan view and interpreted geologic profile are illus-

Jan 1, 1979

By R. J. Sweigard

Estimated costs and revenues can be used in the evaluation of post- mining land use alternatives. However, post-mining land use decisions have to be made in an environment complicated by several additional factors. These factors, including cultural, natural, and managerial issues, are not as easily quantified as costs and revenues but may be more important determinants. There- fore, some approach is needed to attach relative weight to the various factors. The concept of fuzzy sets assembled into a structured hierarchy facilitates analysis of the relative value of individual factors and their impact upon each alternative under consideration. In this paper, a method is presented which employs fuzzy set analysis to evaluate postmining land use plans on the basis of these nonquantitative factors.

Jan 1, 1986

By R. L. Garrett

The quality of mineral additives used 1n a drilling fluid (mud) can dramatically affect the fluid's properties and the overall cost of drilling an oil or gas well. The principally used minerals are bentonite, barite, barite/hematite blends and hematite alone. The high specific gravity minerals, barite and hematite, are used to increase drilling fluid density. Bentonite clay is used to increase drilling fluid viscosity, gel strength and to provide a low permeability filter cake. A multi-million dollar investment in a well and the safety of the personnel on the drilling rig can depend on how effectively these mud additives perform with other constituents in the mud. This paper points out effects caused by small amounts of certain carbonate and sulfide mineral impurities in barite or hematite and how polymeric extender additives in bentonites contribute to unpredictable behavior of a mud. Effects like these are the reason why oil companies who use these materials sometimes set their own quality standards beyond those already specified in API Spec. 13A. Also discussed in this paper are the current standardization activities in API Committee 13 on these minerals.

Jan 1, 1986

By K. Zabrusky

Epithermal vein systems are often modeled as simple, discrete high grade structures within low grade host rock. However, geologic setting and structural preparation influence how such vein systems form. In structurally complex areas, veins may follow several structural trends and occur on a variety of scales. Geologic and grade modeling within such complex structural regimes can be difficult as individual veins cannot be delineated from host rock based on grade alone. Structurally complex areas require a different approach than traditional discrete vein modeling. Presented herein is a study of a structurally complex area that hosts vein mineralization to be mined underground. All veins could not be modeled discretely, so an alternate approach was needed. Major structures were modeled using surface and underground mapping and were then used to create a structural trend for the area. This trend was used to guide 3D grade shell construction. The grade shells replaced 3D vein solids for grade estimation in order to mitigate the influence of high grade samples. Structurally guided grade shell construction offers a more effective modeling method than discrete vein modeling in deposits that are structurally complex.

Feb 23, 2014

By R. C. Emmett

Waste treatment in the mining industry is by no means a new problem to this field. In a sense, the entire process from ore to finished product is one of waste treatment - the separation of a relatively minor quantity of desired component from valueless material. Where it has been necess-ary or economical to practice conventional waste treatment or pollution control methods, such as dust collection, water recovery from tailings, or impounding of residues for future treatment, this has been done. Generally the containment of hazardous pollutants such as arsenic and cyanide also has been followed in modern times. But it is only recently, with the public outcry for the elimination of all forms of pollution, "that the industry has been forced to solve what often appears to be a myriad of difficult and costly waste treatment problems, or be faced with the alternative of closing down the operation. It is the objective of this paper to describe new as well as conventional approaches to these problems, specifically as might be applicable to liquid-solids separation methods. Host wastes in the industry are present either as solutions or slurries, or can be most advantageously handled by conversion to this form, such as in scrubbing noxious gases and dusts with water. Separation of the solids and purification of the aqueous effluents are, therefore, often the principle problems.

Jan 1, 1971

By Karin Bäppler

"When considering large-scale infrastructure projects worldwide special attention has to be paid to the large diameter tunnel construction projects that were successfully completed in the Southern Hemisphere. The projects that are highlighted in this paper are large-scale infrastructure projects in the sector of transport. In focus are four road tunnel projects that were constructed in Australia and New Zealand using mechanized tunnelling technology. The tunnel boring machines (TBMs) that were reliably applied to these four major projects all exceed the bore diameter of 12 meters. These TBMs are therefore in the range of large to very large diameter TBMs. The technology used demonstrates state of the art technology with tailored tunnelling technology adapted to the specific project demands. Two Double Shielded Hard Rock TBMs (Ø 12.35 meters) were used for the construction of the Clem Jones Tunnel in Brisbane crossing beneath the Brisbane River and these two machines have been reused for the excavation of a 4.3km long two-lane highway tunnel for Legacy Way in Brisbane creating a new traffic artery towards the city centre. Two EPB Shields (Ø 12.48 meters) excavated and lined the twin-tube road tunnel for the Brisbane Airport Link. Excavation diameters in excess of 14 meters, such as the Earth Pressure Balance Shield (Ø 14.41 meters) involved in the Waterview Connection Project in New Zealand, are understood in the tunnelling industry as very large diameters. The machine is customized to the requirements and subsurface conditions of Auckland. The paper spotlights the large to very large diameter TBMs that were used and focuses on the comprehensive solutions developed by the machine manufacturer to provide a system with benefits for the contractor especially for the Waterview Project. INTRODUCTION Extensive large-scale road infrastructure projects like the ones implemented in Brisbane (Australia) and currently under construction in Auckland (New Zealand) show the tendency of today’s infrastructure construction projects. Functional infrastructures need to be put in place to cope with the demand of mobility and flexibility of people living in cities and metropolises. Impact during construction work to people or environment has to be kept as low as possible to ensure the quality of life is not disrupted."

Jan 1, 2016

By Nikolaos Syrtariotis, Mark Berger, Timothy O’Brien, Vojtech Gall

The Northeast Corridor Superconducting Maglev Project (SCMAGLEV) entails construction of a high-speed train system between Washington, DC and New York City, with the first leg between Washington and Baltimore, MD. This innovative project will shorten travel times between Washington DC and Baltimore to approximately 15 minutes, and connect Washington, DC to New York City in under an hour. In 2021 the draft EIS is expected to be issued for comment with a Final EIS/ROD anticipated by early 2022. This paper provides an update on the project as presented in Gall et al. (2020) and discusses the economic and environmental benefits, preferred alignment alternative, preliminary staging and launching of the TBMs for construction, and preliminary station design.

Jun 13, 2021

By George I. Staber

This paper is a brief review of the recent history, and the present status of, of the program designed to develop practical new processes for producing pipeline quality gas from coal. Clean synthetic pipeline-quality gas from coal became a major objective during 1971. Agreement was reached with the American Gas Association, Inc., to cosponsor a $120 million, 4-year program to be funded $80 million by Government and $40 million by American Gas Association. The program was first announced by President Nixon in his Energy Message on June 4, 1971, and a portion of the additional funds needed for the program was approved by the Congress in the December 1971 supplemental budget action. A natural gas shortage has developed in the United States and every indication is that it will worsen. Many transmission and distribution companies have already been forced to curtail sales because of the shortage. Large sums are being committed to systems needed to bring liquefied natural gas from abroad and to plants to manufacture synthetic natural gas from petroleum--also largely imported. On the other hand, there is sufficient domestic coal to supply all of the needed gas through the next century. This accelerated program is designed to provide processes for making gas from coal at costs, including security costs, below the imported alternates. As outlined in the President's Energy Message, OCR and A.G.A. have accelerated the coal gasification program to make it possible to construct and operate a "demonstration plant" (semicommercial size) after 1975. Several processes, in various stages of development as will be described later, are being supported. Concurrently, the overall program will be constantly monitored and evaluated with the assistance of an independent, unbiased contractor. C F Braun of Alhambra, California, was selected for this task and has been actively engaged in it for the last several months. Through continuing studies of the various processes and subprocesses as the pilot plant program continues, optimums will be discerned. These will serve as

Jan 1, 1972

By C. Haycocks

Damage prediction during multi-seam mining is an essential precursor to optimizing mine design. Ground control problems associated with interaction are influenced by both fixed geological and site conditions as well as mining variables which may be controlled to varying degrees. To quantify interaction effects across an affected seam a hazard map approach was selected, which allows interaction data to be presented in a form that can facilitate future planning. Study mines were analyzed using boreholes as sources of geological and spatial data, together with information from mine maps which gives the extent of mining activity. To demonstrate the method the safety factor against interactively caused shear failure in the lower seam roof was computed. Input data included depth of cover, inner burden thickness, remnant pillar size, extraction ratio, immediate roof type, seam thickness, percent sand-stone, and rock strength values. These safety factors were then contoured to produce a hazard map. An assumption was made to assign a high safety factor at the outcrop line to permit realistic contouring of the safety factors. The software also allowed mine workings to be drawn onto the map to facilitate interpretation of the overall results. Hazard analysis permits delineation of unsuitable mining areas within a seam. The application of the method for refining mine design and improving reserve recovery is verified using case studies.

Jan 1, 1992

By R. E. J. Putman

Rising demand, artificial market conditions, increased overseas competition, and a fluctuating international situation have brought ever increasing pressures to bear on the nonferrous metals industries, and particularly in the United States, Although capacity is being expanded by the construction of new plants and the development of new ore deposits, increasing attention is being focused on the possibilities of improving the performance of the existing installations and of getting the most out of the new equipment now installed. At first sight the task appears formidable. Based on raw materials which are nonhomogeneous, and possessing characteristics which are hard to quantify, even the processes by which the values in the ores are concentrated and extracted are in many cases not fully understood. The necessary analytical equipment and transducers demanded by these industries have also been slow in development and their earlier absence has hampered the application of modern control technology, This is reflected in plants which have been designed for ease of manual rather than automatic control, and in which the application of control techniques at first sight appears economically prohibitive. However, in any industry progress often comes only in small steps, It may be that by the wise choice of limited objectives and perhaps only partial solutions, substantial improvements in plant performance can be implemented now, and with only a modest investment. If modern control equipment is chosen of the type which can be reprogrammed, advantage can be taken later of more sophisticated solutions as the technology of the industry advances. This task of improving plant performance can and must be commenced even though our knowledge is incomplete. The experience of a related mineral consuming industry, with similar problems in the past, can be encouraging.

Jan 1, 1967

By Lawrence Lien

The reduced need for traditionally trained and educated personnel in the mining industry is systemic to the changing mining industry. Universities and other training institutions are meeting the traditional skill needs required by the industry, but are the skill needs going to be the same in the near future? The answer may be no. Mining is changing because of increased liabilities and costs of environmental and safety is-sues; lower grades of minerals in traditional mining activities and the advent of new bio-chemical processes and robotic equipment. More productive and economic alternatives, and larger, more sophisticated and automatic equipment, are also changing the industry. Engineering is more specific, accurate, precise and expensive. Measurement is more thorough and timely of progress, production, costs and productivity. And, the industry will likely be engaging in more undersea mining, possibly space-based processing, less human interaction and more remote control of events than was previously thought possible.

Jan 1, 2011

By William H. Pomroy

This report describes research leading to the design, prototype fabrication, and successful in-mine proof-of-concept testing of two improved stench fire warning systems for underground noncoal mines. The stench system, widely used in underground noncoal mines to warn of fire or other emergency suffers several serious shortcomings, including the toxicity of the odorant leading to debility in miners; reactivity of the odorant with iron oxide, resulting in unreliable warning because the odor may fade when transported long distances in steel pipe; lack of control over the rate at which agent is released into the air-stream, resulting in some work areas receiving unbearably high stench concentrations and other areas being missed altogether; lack of visual indication of system status, valve positions, or proper system operation; and excessively long stench transit times. In 1979, the Bureau of Mines, U.S. Department of the Interior, began research to upgrade the stench warning system. Two systems were subsequently developed which offer significant advantages over current systems.

Jan 1, 1984

By R. Vogt, H. C. Mult, F. L. Wilke

INTRODUCTION At present, the capability of production planning software based on Linear Programming (LP) is still limited to the optimization of the single LP-run. This is due to the LP-model itself which cannot consider the interdependencies between individual LP- runs. With regard to planning of selective mining this limited way of optimization frequently leads to situations, where the remaining and accessible ore blocks do no longer allow to produce ROM-ore in the qualitative composition required by the ore processing plant. However, many of the aspects taken into consideration when setting up production plans built from mutually dependent LP-runs cannot be modelled in a system of linear equations. They are thus unsuited for treatment with LP and have to be taken care of by the planning engineer without any assistance by the system. The KBS currently under development is intended to assist the planning engineer in designing a production plan under special consideration of the combination of consecutive LP-runs and blending beds. It is not necessarily intended to find the optimum solution within a given planning situation which is, anyway, hard to determine due to the multitude of influences. The objective is rather to work out a good and - from the practical point of view - feasible production plan. The new aspect with respect to mine planning is the integration of expert knowledge and experiences via the KBS into the planning process in order to support the planning engineer. The planning system is being developed in close cooperation with an iron-ore open pit mine. COMPONENTS OF THE PLANNING SYSTEM The software is being developed on a workstation under UNIX and comprises the components LP, CAD-module and the KBS. The applied multi-goal LP-algorithm is an in-house development of the Department of Mining Engineering at Technical University Berlin. It was already successfully implemented within other mine planning programmes and was only slightly adapted to the specific needs of the present system. Within individual LP- runs it finds the optimum qualitative composition of ore production in the sense of the selected optimizing criterion and under the given restrictions: i.e. it determines tonnages to be mined from blocks in order to optimally meet the requirements of the ore pro- cessing plant. A CAD-module based on the commercial SURPAC package in combination with a simulation device is used to graphically depict the block model and progress of mining. Both LP-algorithm and CAD-package are integrated in the KBS. It has been decided to use the shell NEXPERT OBJECT as it is a hybrid system which supports both rule-based and object-oriented knowledge representation. MINE-MODEL AND LP-MODEL KBS have to be tailor-made for specific planning problems. Therefore, it had to be decided which specifications of the iron-ore mine should be represented in the model. As the limited possibilities of a university institute do not allow to develop a KBS for mine planning which is ready to use in industry, it was decided to concentrate on those characteristics that can be regarded as typical for iron-ore surface mines and that seemed to be suited for treatment with knowledge-based techniques. The following chapter summarizes the most important features of the mine model. The description of the requirements to the mine's sales products is followed by an outline of the applied LP-model. Mine model • The model of the mine as it is used for planning consists of • the block model of the deposit, • the mobile equipment, • stockpiles and blending bed and • the requirements to the sales products. The deposit is described by a block model which contains data on the chemical composition, LOI, grain size and tonnages. Grain size was included as it is important for the two sales products of the mine. Furthermore, it is known whichs blocks require and which don't require blasting; this is relevant to the assignment of loading equipment to individual blocks. The blocks are devided in three categories: • ore, which will directly be taken to the blending bed; • waste, which will be put on the waste dump; and • blocks which will be either transported to the blending bed, to stockpiles or to the waste dump depending on the specific planning situation. This decision is made during planning. Neighboring blocks are combined in mining areas to which the loading equipment is individually assigned. Mobile equipment comprises shovels and wheel-loaders as well as trucks. The characteristics of the loading equipment are important for their ability to load different blocks and for the permissible degree of their re-positioning etc. The mine disposes of a blending bed for homogenization of the production, of a waste dump, and of several stockpiles with different ore qualities. The requirement to make only limited use of the stockpiles for economic reasons is included in the KBS. According to long term planning two commercial products have to be produced, which differ both in grain size and qualitative composition (TABLE 1). Their mass-proportions in the blending bed have to be within a fixed range. Not considered in long term planning is the occasional need for lump ore, which occurs at very short notice and has to be produced in a "campaign-like" manner. This requires the total re-arrangement of all plans for on- coming blending beds and would therefore be ideally suited for

Jan 1, 1996

By Todd Burchett

Mining engineers spend countless hours and resources when designing a new underground coal mine. Their primary objective is to design the safest and most efficient operating mine with regards to coal production. A key variable often overlooked in this design stage is the slope conveyor. Typically, a slope conveyor is expected to operate with a 98-percent or higher availability. However, too often little effort is put forth by the mining engineer to optimize its design. Coal companies will rely on engineering, procurement, construction and management (EPCM) companies for the preliminary design, because the slope conveyor will be considered part of the surface material handling processes. This preliminary design will be used when soliciting quotations for the slope conveyor. Unfortunately, EPCMs may not have enough expertise with conveyors to optimize the design. This expertise is available with an original equipment manufacture (OEM) of conveyors, which ultimately may be responsible for supplying the slope conveyor. Each OEM will provide a bid package that represents what it considers to be the optimal design.

Jan 1, 2013

By R. A. Winters

At the operations level, productivity is a principle key to profitability. If you are competing with other mines that are paying roughly the same wage rate and the same prices for capital, materials, and energy, the only way your profit can be greater is by producing more output per unit of input. Mines with higher productivity have higher profit margins. Higher profit margins lead to greater operating cash flow, and cash flow is what distinguishes a dog from a cash cow. The turnaround in U.S. metals during the 1980s was in large part due to incredible improvements in productivity. According to statistics compiled by Kaufmann, 1991, labor productivity, measured as tonnes of primary production/manhour, increased 64% in steel, 94% in copper, 75% in lead, 143% in zinc, 132% in molybdenum, and 75% in gold. These improvements were hard won. However, with most modernization programs now complete, measuring and monitoring productivity becomes even more important as producers strive to maintain the gains they have achieved.

Jan 1, 1993