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By Bill Linville

During fiscal year 1969, the Bureau of Mines was engaged in 66 projects to improve methods for producing and utilizing petroleum. Programs directed toward the continued conservation of this natural resource, including crude oil, natural gas, and oil shale, were carried out through research performed at four laboratories supervised and supported by administrative personnel of this Bureau of the Department of the Interior. Over 100 technical papers and reports were published by the Bureau or others based on this research, and numerous other reports were prepared for U.S. Government agencies, State agencies, and organizations of the petroleum and natural gas industry engaged in cooperative research programs with the Bureau.

Jan 1, 1971

By Michael J. Brown

Load testing is important for controlling the quality of piled foundations. The Statnamic test is an alternative to existing testing methods with a load duration that lies between that for static and dynamic tests. Current methods of analysis offer excellent correlation between static and Statnamic tests for coarse-grained soils but often over-predict the capacity for fine-grained soils. Thus a calibration chamber is being used to produce instrumented beds of clay with reproducible properties. A model pile placed in the beds can be loaded at varying rates using a computer controlled servo-hydraulic system. Results from the modelling will be used to improve methods of analysis and govern the design of a full-scale study. Initial results suggest the rate effect can be represented by a power law relating pile velocity and resistance. Statnamic loading of the model pile produced large negative pore pressures in the clay bed.

Jan 1, 2002

By F. G. Crack, R. V. Ramani, R. L. Frantz

Management for mine construction and development differs from that needed for routine mine production and maintenance. An integrated approach to managing mine development projects must consider contract documents; management organization of a project; the project manager's role and the field supervisor's responsibility; and the use of scientific techniques for planning, scheduling, executing, and controlling projects. Professional project management encompasses the following: • Preparing contract documents that establish technical and financial schedules, and detail the responsibility for the physical work commitment. • Developing a project's organizational structure, to clearly define the roles of the project manager and the field supervisors. • Establishing project management and field supervisor relationships, to avoid ambiguity in assigning responsibility and to ensure desired project progress. • Using management science techniques, particularly networking techniques such as the critical path method for planning scheduling, executing, and controlling projects. Project Versus Production Management Project management differs from routine production management in the following ways: • Uniqueness: A project is unique. Production operations tend to be repetitive. The magnitude of one-time capital expenditures for many facets of mine development warrant special skills and attention. These professional project development skills must already be available by prior experience in the management team. • Personnel: In projects, personnel are usually assigned on a specialty basis and frequently change with the project activity. On the other hand, production personnel work together, more or less permanently. • Management Structure: In a project there may be several staff-line relationships that are not clearly defined and change with changing project activities. In a production situation, the lines of communication and authority are usually well defined. • Time Frame: A difference between project and routine production management is that project activities have comparatively less well defined durations and often tend to be relatively short-term. Production usually has both long-term and short-term plans and well defined long-term and shor-term goals. In project management, formal, critical, short-term reviews are frequently required. In production management, five year plans can be formally adjusted quarterly and annually. Short-term weekly or daily reviews can be informal. • Response to Delays: Delays in a development project may occur without anyone being immediately aware of their existence or suspecting the magnitude of consequence. In contrast, any delays in the production process can be easily identified from prior results comparison. Additionally, the response is quick, usually in a set routine. This can be traced back to the management structure and personnel. • Control Techniques: Measurements of project progress for control are not easily made due to the variety of activities that are carried on at the same time by different work groups. The yard-sticks of performance measurement for individual activities, let alone for the total project, are not easily established. However, due to the difficulty in detecting project delays, a workable control system is vitally important to a project manager. To apply a scientific project control technique such as "management by exception" requires specific planning and monitoring from the project manager for each activity in the project. Production and productivity are quick and effective yard-sticks of measuring performance in a routine operation. Control techniques required in production management usually revolve around these measures. Construction Contracts The construction contract is an important document that establishes contract scope, technical and financial details of the work, and achievement deadlines. It may also serve as the contract document to pay for work done and to verify field progress with planned progress. In practice, it is a good idea to develop a job-specific contract. This whole area is replete with legal precedence and procedures, and it is not the intent here to deal with the intricacies of establishing a contract document. But it is necessary to have an understanding of major contract types. Construction contracts are extremely important legal documents. They may vary in work specifications and enforcement of the provisions. Due to their nature, they must be composed with legal help and will take some time to compile. Even with all the precautions and provisions, it is not uncommon to find owner and contractor disagreeing. Therefore, it is important to include a way to resolve any difference quickly and to incorporate aspects of the contract as part of an overall management control tool for efficient project management.

Jan 7, 1982

By H. E. Urtubia, C. W. Bailey

"BHP-Billiton’s Minera Escondida Limitada is one of the world’s largest copper producers. It treats a combined 88 million tons of copper ore per year through its two concentrators: Los Colorados and Laguna Seca. Over the past three years, metallurgical sampling has been performed at the Laguna Seca concentrator to calibrate both the JKSimMet and JKSimFloat grinding and flotation simulators. In the past, the calibrated simulators have been used to predict the effect of changes in operating conditions in the grinding and flotation circuits separately. To assist in the development of future processing options, predictions were required of the effect of changing grinding circuit conditions on flotation performance. This was achieved by using an integrated grinding and flotation simulation. The grinding circuit performance was predicted under different operating conditions (such as tonnage rate and product grind size) using JKSimMet, and these results were then used in JKSimFloat to predict the flotation performance for the new grinding circuit product. This combination of the simulators allows both the effects of residence time and grind size on flotation performance to be investigated.This paper presents the first combined grinding and simulation modelling and simulation case study using JKSimMet and JKSimFloat. The modelling and simulation methodologies for the grinding and flotation circuits are discussed along with the circuit simulations that were performed. The simulator predictions are presented in conjunction with independent laboratory results of the new operating conditions. The ability to predict flotation circuit performance based on changes in grinding circuit performance is also discussed. This methodology provides improved predictions of flotation circuit performance when grinding circuit changes (including grinding capacity increases) are made.INTRODUCTIONOver the past decade, the grinding and flotation research groups at the Julius Krutschnitt Minerals Research Centre - JKMRC (Brisbane, Australia), University of Cape Town (Cape Town, South Africa) and McGill University (Montreal, Canada) have been developing a methodology for optimising grinding and flotation plants using actual plant data together with semi-empirical sub-process models. The project is being conducted as part of the Australian Minerals Industry Research Association (AMIRA) P9 Project, titled “The Optimisation of Mineral Processes by Modelling and Simulation”. The project first commenced in 1962 and is currently in its “Nth” phase."

Jan 1, 2007

By M. Lombardero, J. Garcia-Guinea, J. Taboada, B. W. Roberts

The structural, textural and mineralogical properties of the slate formations of NW Spain make it the most important district in the world for quarrying roofing slates. Over the past 10 years the introduction of new methods has increased yields from 2 to 13%. The main factors affecting quality are quartz grain size less than 75 micrometres, homogeneity of slaty cleavage and S0-S1 intersection angle, very low metamorphic grade, absence of secondary foliation, beds 10-12 m thick and low content of oxidisable Fe sulphides. The two main controls on fissility are lithology and deformation accompanied by metamorphism. The minimum natural block size should be 0.6 m3 but this volume can be reduced for modern cutting tools such as diamond wire, chain and circular saws. Structural analysis is crucial in exploration and quarrying, as shown by the prospecting methodology applied at Dominio de Truchas in central Spain and the computer analysis of rock mass discontinuities at Casaio quarry

Jun 19, 1905

Often plant performance suffers as a result of poor control. Poor control leads to low mill throughputs, poor classification and less than satisfactory concentrate grades and overall recoveries. By using the appropriate control tools, substantial gains in plant performance can be made. Mintek?s MillStar and FloatStar controllers have been implemented at various sites across the world. The MillStar controller incorporates leading technology that controls process units from the mill feed through to the flotation feed. Typical results show that milling circuit throughput is increased by 6-10 % and the final product grind size is tightly controlled, thereby enhancing flotation performance. The FloatStar controller is aimed at stabilising and optimising flotation circuits. Through improved level control alone, recovery improvements of up to 1 % have been achieved. Furthermore, by using on-line grade analysers, the controller stabilises final concentrate grades, whilst maximising flotation recovery.

Jan 1, 2005

By J Weir

Accurate sampling of slurry streams is extremely important for metallurgical accounting in mining operations, not only for measuring the ore grade from the mine, but also for measuring the recovery of mineral by the mineral processing plant. Accurate sampling is also required for intermediate streams in complex circuits for determining efficiencies of processing units within the plant. As the profitability of the minerals industry is squeezed more with time, greater emphasis is being placed on efficient use of the resource and accountability of the various sections of the mining operations. This has led to increased awareness and interest in obtaining statistically correct sampling across the operations. Accurate sampling is not only required for metallurgical accounting, but is also required for on-line analysis of the slurry streams for elemental analysis and for particle size. Sampling of slurry streams for metallurgical accounting purposes has traditionally been one of the areas of concern in mineral processing plants. In the first instance, the sampler must be designed to comply with the fundamental principles of sampling theory and must provide a representative sample of the slurry stream. In the second instance, the sampler must continue to reliably provide a representative sample, regardless of wear of the equipment or build up of solids with time and other operating issues. To-date the main type of sampler that has been used in mineral processing plants for metallurgical accounting has been the Cross-Cut sampler. These have a cutter that periodically cuts across the full slurry stream. For large flow slurry streams, these are often followed by a secondary and perhaps a tertiary sampler, to reduce the flow-rate or sample, to a manageable size. This paper discusses a new method of sampling slurry streams that has been developed by Thermo Gamma-Metrics, previously known as Amdel Instrumentation. The new samplers overcome many of the problems associated with cross-cut samplers while providing a sample which is representative of the main stream, throughout the life of the sampling system. The sampler is called the SamStat (Sampling Station) and it is now proven in many applications across many countries and mineral processing plants (PGMs, Cu/Au, Pb/Zn, etc).

Jan 1, 2002

By T. R. Ellis

The vast majority of valuations produced for mineral properties using the net present value method provide an estimate of Investment Value or Use Value. Such an estimate can be a long way from the price that the property would sell at if placed on the market. Indicators from the market need to be used to validate or modify the net present value calculation. The comparable sales and replacement cost approaches used in the appraisal of urban buildings generally fail us in the appraisal of mineral properties. Other methods of sales analysis are introduced. Guidelines for what a minerals appraisal report should contain are presented.

Jan 1, 2000

By Robert L. Lappi

Eight interburden handling concepts are developed for multiple seam area mine stripping operations in central and western United States. They are based on data gathered and analyzed during field surveys, literature reviews and visits to state regulatory agencies in five states. It is concluded that improvement of reclamation practices through selective interburden handling techniques is possible at lower operating costs than currently incurred. Specific multiple seam mining systems are discussed in this report.

Jan 1, 1980

By Marco Muñoz

La mina Porvenir, perteneciente al Grupo Milpo, está ubicada en Cerro de Pasco, destacándose por la corporación de equipos de alta tecnología minera adecuada a sus operaciones. En ese sentido, el presente texto señala el sistema de gestión operativa aplicado en la mina Porvenir con el objetivo de apoyar las operaciones, ya que la tecnología de información permite manejar complejidad y mejorar la calidad de las decisiones.

Jul 17, 2000

A recent Evening Post Headline read 'Officialdoms Inertia Risking Millions in Growth Strategy'. The article beneath that headline outlined the difficulties encountered by the Government's growth strategy projects and included the paragraph 'public efforts by Government to brush up communication of the widespread nature of its growth strategy is believed to have been matched by efforts in private by some ministers to overcome their frustration at the constant delay while reports and paper work are moved between departments and through the system'. The article went on to point out that these delays could cost New Zealand millions of dollars in lost overseas exchange savings. We as responsible citizens should be appalled or at least concerned that such costly delays should or even could occur. But those on the outside of the system who spend much of their working life prodding, reminding, pleading, cajoling, even begging, the bureaucracy should be excused a smirk or a smile or even a good belly laugh. The Minister is usually a part of the bureaucracy passing judgment on someone else's proposals. This time the Government has plans of its own. Plans which it wishes to see implemented as rapidly as possible and even with the assistance of the precautionary National Development Act with its 'fast track' provisions those plans have got bogged down in the bureaucratic machine which this Government has done as much as any other to create. In the circumstances, the thought of Her Majesty's Ministers frustrated at the constant delay while reports and paper work are moved between departments and through the system is not unpleasing.

Jan 1, 1982

By Marwan M. Mohammed, Hani S. Mitri, Wilfrid Comeaul, Baoyao Tang

In many parts of the world, rockbursts have become a major problem of mining at depth. As orebodies are being mined deeper, rockburst phenomena have become familiar to deep hard rock mines. Rockbursts are generally characterised by sudden release of energy in a volume of highly stressed rock, which can cause local violent failure of the rock mass around the opening. One method of controlling these failures is to precondition the rock mass by detonating fully confined explosive charges at the appropriate locations. This method known as destress blasting, was first tried in the deep South African gold mines (Roux et al., 1957), and was widely used later in Canada, United States, France, Poland and Japan.

Jan 1, 1999

By Richard J. Mainiero

The Bureau of Mines conducted research to evaluate the optimum design for a rock-breaking explosive charge that could be fired unconfined in a gassy or dusty coal mine without the danger of igniting the flammable atmosphere. Charges of various shapes, with and without cavities, were tested in a gallery using 3-by 3-by l-ft concrete blocks as simulated boulders. For these tests the optimum charge, in terms of cost, weight, and convenience in handling, consisted of a flat l-1/2-lb charge of permissible explosive seven-eighths of an inch thick and 7 in in diameter encased in a l/2-in thick layer of fine salt (NaCI). This work demonstrated that it should be possible to produce an inexpensive explosive rock-breaker charge that would be safe to use in underground coal mines.

Jan 1, 1982

By Adam Chrzanowski, Eugene E. Derenyi, Peter Wilson

"The rapid growth of the mining industry in Canada necessitates a reevaluation of existing mining surveying techniques and the development of new methods. In this connection, the Department of Surveying Engineering at the University of New Brunswick initiated a research program, and the major points of investigation conducted to date are as follows: 1. Based on practical experience and theoretical studies, all factors influencing classical shaft-plumbing procedures were analyzed. Refined methods were developed to increase accuracy. 2. The performance of electronic and optical distance-measuring instruments in underground conditions were investigated. In this connection, test measurements were made in various mines, employing four types of Tellurometers, two models of Geodimeters and a proto-type optical range-finder. 3. Tests were conducted and methods developed for the mapping of large underground chambers by photo-grammetric means. The aforementioned points are discussed at some length in the paper. The authors have also indicated areas where further research is needed and suggested ways and means to improve and modernize mining surveying as a whole throughout Canada."

Jan 1, 1967

By Alexander Nikolic

The paper presents the foundation design and construction of a landmark urban redevelopment scheme in central London, UK. The scheme comprises the new Tottenham Court Road Underground station, Crossrail interchange box and associated over-site commercial development. The paper focuses on the design, procurement and construction of large diameter bored piles, up to 68m in depth, which form the foundation support system for the over-site commercial development at Denmark Place. The congestion below ground required an intricate foundation design solution which has been a catalyst for developing innovative load transfer arrangements and has resulted in the advancement of pile construction technology in the UK. The foundation system was also designed to cater for the construction of two significant elements of proposed below ground infrastructure. Selected large diameter piles have been constructed within 1.1m of live underground railway tunnels. An innovative D-shaped pile was constructed in a zone subject to particular spatial constraints. The proposed Crossrail tunnels will be bored within 1m of selected over-site development piles. In addition, a 30m deep excavation forming a new escalator box will be constructed in direct contact with the over-site development piles. The stakeholder engagement process is described together with the foundation design development and buildability assessment. The benefits from early collaboration between the designers and specialist contractors are highlighted. From an analytical design perspective, the entire foundation construction sequence was modelled in detail in order to assess the soil structure interaction and any potential adverse effects on existing elements of underground infrastructure. The results from the three dimensional numerical modelling simulation are compared with field monitoring data.

Jan 1, 2011

For establishing sustainable material cycle process in human system, a brand new concept should be created, which could recycle the waste materials, which are land-filled and discarded under present economical situation. The concept of 'RtoS' (Reserve (of waste) to Stock) to create 'artificial deposit' of the materials concentrate is one of the best ideas to be applied. From this viewpoint, separation technology, in especial, solid phase separation such as mineral processing technology contributes much to the concentration, making 'artificial deposit' with less energy consumption compared with melting and/or dissolving technologies. Results of rare metals concentration in the e-waste are also introduced as an example with combining novel comminution and parts/powder separation.

Sep 13, 2010

By Emad W. Shublaq

Contractual site plans are implemented for executing pile foundations (5 x 5) at segmental concrete bridge. Project schedule demands have forced the contractor to find out the most economical procedure in achieving the goal. This paper presents a site management technique which is applied by the Contractor. This was found to be fruitful and as much as 60% saving was gained.

Jan 1, 1992

By John Watson

The earliest known records related to mining document in dramatic terms the fact that mining methods have undergone significant change over the centuries. Wooden wedges, hammers and chisels, “fne setting”, to name a few, were the frst tools used to extract ore .or quarry rock for civilization. These inefficient tools and unsafe practices have been replaced today with some of the highest technology known to man. At the heart of most mining operations is the blasting program which utilizes one of the most efficient tools ever invented.. . explosives. Ever since they were invented, miners have been searching for more efficient products and methods with which to harness this “tool” and make it safer, reliable, and more eficient to use.

Jan 1, 1997

By E. McCullough, D. Preece, M. Ortel

Geophysical explosive charges are used in mineral resource exploration. They are detonated subsurface and radiate sonic waves into ground monitors, which detect the vibration waves and their interaction with underlying geologic strata. Geophysicists perform computer analyses of the waves reflected from the strata to determine their depth and thickness (Strobel, Berger & Schaefer, 2012). The purpose of this research is to determine how the detonating explosive charge interacts with the adjacent ground and how the induced waves propagate through the surrounding medium. Furthermore, it is necessary to optimize the location of the initiation point within the charge. Establishing both the direction and intensity of the waves will allow geoscientists to refine and optimize geophysical studies that employ explosive charges.

Jan 1, 2013

By H. M. Lizama, R. L. Stephens

Secondary leaching of previously leached supergene copper ore has been developed and implemented at Teck’s Quebrada Blanca operations. This consists of using in-situ leaching techniques aided by geophysics to recover the residual metal value from dormant copper leaching heaps. These heaps of crushed and agglomerated ore had been leached 20 years previously but still contained significant copper values. The concept was first tested on a 3,200 m² sector, where injection wells introduced leaching solution into a production zone and electro-resistivity tomography was used to track solution movement within. Operating parameters such as well spacing and injection flow rates were determined. Copper recovery and leaching performance were evaluated based on solution and metallurgical balances. Both ferric leaching and bacterial leaching were enhanced through strategies to pull air into the heap. Positive results from the initial test prompted a larger, industrial pilot test on a 60,000 m² area and 97 injection wells. This larger test obtained a copper recovery of 30% in 457 days. Secondary recovery is now being implemented to all of the abandoned heaps at Quebrada Blanca and has become a production stream. This technology has the potential of wide application to mature copper heap leach operations, and Teck has patented the process and associated methodologies. INTRODUCTION Heap leaching of copper secondary sulphides has been carried out at Quebrada Blanca (QB) since 1994. Ore from the supergene deposit was crushed and agglomerated prior to leaching. Originally, the ore was leached in 6 m lifts stacked one on top of another, known as a static pad configuration. However, in 1998, after the second lift, the operation changed to a dynamic pad configuration; the ore was leached in a single lift and the resulting residues were removed to make way for fresh ore (Yáñez, Ahlborn, & Ramos, 2007). The first two static lifts were left in place and served as a foundation for the dynamic lifts above. Those two buried lifts of leached residues, some 16.8 million tonnes and covering an area of approximately 0.71 million m², remained buried under the dynamic pad.

Jan 1, 2019