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By S. E. Daniel

"Due diligence reviews are an essential part of mineral property acquisitions. One of the primary reasons to complete an environmental review prior to exploration property acquisition is to assess the potential environmental liability. It is critical to identify the potential reclamation costs or existing environmental liability associated with the exploration property. A review of the existing condition of the property and its history can allow prioritization of exploration targets and ease future expenditures for historic damages. IntroductionIn Canada and some other jurisdictions, the purchaser of a property is assumed to know, and is (in the absence of deceit or fraud) financially responsible for, what is purchased. A plea of ignorance, at least from the perspective of environmental liability, is not an acceptable excuse to avoid responsibility (Nelson, 1994). Therefore, if an exploration company (for the purposes of this paper, any organization conducting exploration work) purchases a property that has environmental contamination, the new owner is liable for the cost to reclaim the site to an acceptable level. The cost to reclaim the site is the environmental liability. The new owner is responsible for existing environmental liability of the property, even if the exploration company’s personnel were not aware of the problem. In simplest terms, buyers beware. Therefore, in order to protect the exploration company’s interests, the exploration manager should determine the characteristics of the property of interest prior to purchase or other involvement, and exercise due diligence.The term “due diligence” is often used in the mining industry. To ensure clarity, in this paper’s context, the author has chosen to use the following meaning: “… due diligence is used to describe a detailed data review, generally in connection with the purchase or sale of a mineral property, the approval of a large capital expenditure, or the borrowing of a large sum of money” (Smith, 1997).Directors of the exploration company are held liable for the decisions made, unless they have relied in good faith on,“…a written report of the auditor, or a report of a lawyer, accountant, engineer, appraiser, or other person whose profession lends credibility to a statement made by any such person” (OBCA, 1994)."

Jan 1, 2003

By P To, A Sharp-Paul, S Jones, C Monahan

A key environmental management issue associated with mining projects is tailing disposal. In high rainfall environments this is particularly challenging and generally requires the discharge of excess water from a tailing dam to adjacent streams or coastal waters. Such discharges can potentially have adverse impacts on downstream water quality and the environmental values associated with these waters, such as providing a drinking water supply for local villagers, maintaining a fisheries resource or protecting a fish species of high conservation significance. An alternative to the construction and operation of a conventional tailing dam is Deep Sea Tailing Placement (DSTP). The key features of such a system are:Discharge of the tailing slurry at considerable depth (approximately 120 - 150 m) below the oceanÆs surface. This requires a pipeline to be laid from the process plant to a mix tank, where the tailing is mixed with seawater and entrained air released. The pipeline then continues down the ocean floor to the required discharge depth, which is below the surface mixed layer and the euphotic zone. After discharge, formation of a density current which continues to descend along the ocean floor as long as the slope is sufficiently steep. Final deposition of the tailing in an area where the slope of the ocean floor is insufficient to maintain the density current. This typically occurs at depths of more than 800 m. Water quality issues associated with DSTP include: Impacts on the oceanic water column due to the formation of subsurface plumes which break away from the descending density current. The occurrence of elevated concentrations of contaminants in the interstitial waters of the deposited tailing solids. Fluxes of contaminants from the tailing deposits into the overlying oceanic water column. This paper discusses the water quality aspects of DSTP with particular reference to a case study in Papua New Guinea. The evaluations undertaken as part of the DSTP impact assessment included consideration of both the short- and long-term chemical behaviour of contaminants and bioassays, within the appropriate water quality assessment framework.

Jan 1, 1999

By M. Reuter, C. Schuffeneger, T. Seppälä, L. Holappa

Reaction kinetics of solid-state reduction of chromite pellets (laboratory made and industrial) and lumpy ore was investigated by the thermogravimetric analysis (TGA) technique. Carbon monoxide was used as the reducing agent, with the presence of graphite in proximity to chromite. The experiments were carried out at both rising temperature and constant temperature in the range of 1450 - 1550°C. Scanning electron microscopy was employed to observe and analyse the structure and composition changes of the chromite samples. For the lab-made chromite pellets, the effects of particle size and bentonite addition on the reduction behaviour were studied. The pellet with smaller particle size gave a higher reduction rate. Bentonite addition had slightly negative effect on the reduction rate. When reducing industrial pellets, temperature and CO flow rate had positive influence on the reduction rate. Reduction of lumpy ore took place slower than reduction of a pellet. In all samples, chromite reduction proceeded longer in the outer part of the sample than in the centre part. The porosity of the chromite samples was determined before and after the experiments. The porosity of lumpy chromite increased significantly during the reduction. However, the porosity of lab-made chromite pellet decreases due to sintering effect. The reaction mechanism is discussed on the basis of experimental results and earlier investigations.

Jan 1, 2004

By A. B. Phillips

The Randfontein Estates Gold Mining Company (Witwatersrand) Limited (REGM) operates three metallurgical complexes for the recovery of gold from the Witwatersrand Gold Reefs at the town of Randfontein, 40 kilometers west of Johannesburg. Mining operations in the. area commenced in March 1889 and ceased temporarily in 1965 when the viable ore reserves had been depleted. Exploratory drilling in the 1960's indicated viable deposits of gold in the Elsburg reefs, south of the Witpoortjie Horst Block, _which formed the Southern limit of the previously exploited areas. Three shaft complexes have been established to exploit this area, known as the Cooke secti'on. In 1983 the Doornkop shaft was sunk to the north of the Cooke section to mine Kimberley reef and the South reef.

Jan 1, 1992

Meeting, June 26, 1913).-On the petition of 29 members residing in and near San Francisco, Cal., the San Francisco Local Section was established. The territory of the St. Louis Local Section was established to include the following States and parts thereof: All the State of Missouri ; That part of the State of Illinois south of and including the city of Urbana ; That part of the State of Indiana south of and including the city of Indianapolis ; That. part of the State of Kentucky west of and including the city of Frankfort ; That part Of the State of Tennessee west of and including the city of Nashville That part of the State of Arkansas north of and including the city of Little Rock.

Jan 7, 1913

By T. R. Marrero, J. W. Wilson

The transportation, by water that flows through a pipeline, of coals in the form of water-impermeable cylinders is discussed, and shown to have distinct advantages over other forms of coal transportation, including significantly reduced costs for larger throughputs. The description of the concept comprises various aspects of the system, such as methods for the manufacture of coal logs, their injection into the pipeline, the manner in which they are conveyed in the water in the pipe, and the methods used for their preparation as feed material to electric power stations at the end of the pipeline. It is pointed out that the technology involved in the transportation of coal in the form of logs via pipelines is applicable also to other minerals and commodities.

Jan 1, 1993

By Paul Ross, Harry Burchett, Lou Case, Calvin J. Konya

"The Cumberland River in Harlan, Kentucky has flooded the town for numerous years. TheU.S. Army Corps of Engineers funded a project to divert the river. The project consisted oftunneling through a mountain to divert the river. The approaches to the tunnels requiredcontrolled blasting to create noses to help channel the water and debris into the tunnels.The geologic structure was such that conventional presplitting techniques were notproducing the desired results and were causing severe backbreak. Replacement of the rocknoses with concrete would cost about a million dollars; and therefore it was important tosave them if at all possible. Blasting techniques were developed which allowed the projectto be successfully completed. This paper will discuss the case history of the controlledblasting procedures."

Jan 1, 1993

By Timothy P. Smirnoff, Anthony Stirbys, Amanda Elioff

The construction of the continuing expansion of the Los Angeles Metro System has required the construction of eight new station structures. One contractor proposed, as a construction alternative for the support of excavation of the Hollywood/Vine Station, the use of soil-mix walls instead of the conventional soldier piles and wood lagging. Soldier piles and shotcrete or wood lagging support systems had been generally used on the other sub-way station excavations constructed to date throughout the system. Immediately east of that station and in almost exactly the same geology, the Hollywood/Western Station was being excavated at the same time using a conventional support system. This paper com-pares the performance of these two support systems in the alluvial soils of the Los Angeles Basin.

Jan 1, 1997

The attachment of a spherical particle to a bubble is theoretically investigated under the condition of a mixed sorption coating of a collector. It is shown that the attachment is determined primarily by the hydrodynamic factor involving the displacement of liquid from the gap between a bubble and a particle. The dependence of the attachment on the state of the surface of particle (sorption coating) is due to a change in the boundary conditions on the interface with water both in the case of surfactant chemical sorption and in that of the physical adsorption of oil. It is demonstrated that at large distances the thinning of a interlayer is facilitated by a physically sorbed collector, while near the bubble this is done by a chemically sorbed one.

Jan 1, 1993

By Dale A. Augenstein, S. C. Sun

A primary concern in the solution of any solid waste disposal problem is the characterization of the material. In the past, available methodology for the determination of coal refuse characteristics has been severely limited by the inseparable combination of organic and inorganic matter of which the refuse is comprised. The recent development of an electronic, low temperature asher which removes the organic material without alteration of the inorganic constituents has opened new areas of coal and coal refuse research. This study deals with the development of methodology for the characterization of Pennsylvania anthracite refuse through utilization of the low temperature asher. Seven samples of anthracite refuse were examined for verification of the methodology developed and information concerning the characteristics of the refuse.

Jan 1, 1975

By Jifan X, Yongyu W, Liangjing L

Shallow interception of groundwater is a special dewa- tering form in the specific geological and hydrogeological conditions. It has an economic and technical effect. The roof of the Fankou Lead-zinc deposit is the Hutianqun aquifer made up of the limestone of the upper Carboniferous system. - A "water-bearing basin" is surrounded by the aquifuge and the aquitard below ¦0 m level at the Shiling Hill section in the Hutianqun aquifer. Based on the natural conditions, an interception gallery is excavated at -40 m level out of "the water- bearing basin", the other gallery excavated at ¦0 m level in the poor water-bearing zone of the Jinxing Hill. During 20 years of experience, the better interception effects have been gained.

Jan 1, 1988

By W. J. Carlson, I. Iwasaki

A previous article reported a combination process for recovering both metallic iron and metallic manganese from the manganiferous iron ores of the Cuyuna Range in Minnesota.' In this process, the iron was recovered by direct reduction and magnetic separation and the manganese was recovered from the nonmagnetic tailing by leaching and electrolysis. The current efficiency during the electrolysis of manganese is quite low, in the range of 60 to 70%, due to the simultaneous plating of hydrogen.2,3 The parameters that affect the current efficiency are (1) the concentrations of the manganese ion and the ammonium sulfate buffer, (2) the effect of autoxidant, (3) temperature, (4) pH, and (5) current density. To study the plating characteristics of manganese metal.

Jan 1, 1969

By Charles E. Whieldon

This report presents the results of a study on part of the Smithfield oilfield, Wetzel County, W. Va. The primary purpose of the investigation was to determine the original and the present volume of stock-tank oil in the formations and to investigate the feasibility of waterflooding the Gordon Stray, Gordon, and Fourth sands underlying the I. D. Morgan lease. The study was based on laboratory core analyses, geophysical well logs, geologic considerations, and various field prediction data from the I. D. Morgan lease. The Bureau found that, of the three sands cored, the Gordon Sand was the best prospect for waterflooding, and that a properly engineered water flood should recover 136 to 230 barrels of oil per acre-foot from this formation.

Jan 1, 1967

By W. J. Keep

Some explanation of methods of testing will be given before presenting the record of a series of physical tests of aluminum, other metals and alloys. I. The Methods Employed and Meaning of Diagrams. The test-bars used, 12 inches long and 4 inch square, are cast in green sand, with chills bedded in such a way that the ends of the bar run against them. By splitting the ends of the bar the depth of chill can be measured. The chills being held in the mould 121/8 inches apart, the space between the end of the bar and the face of the chill, after both are alike cold, is the amount of shrinkage, and is recorded in thousandths of an inch per foot.

Jan 1, 1890

Retreat longwall method with re-use of gateroad has been traditionally employed in Japan, mainly because of the advantage of higher recovery. But the Miike Colliery has newly introduced the interpanel-pillar system to maximize the production efficiency. The Department of Mining, Kyushu University, in cooperation with the Miike Colliery and the Coal Mining Research Center (CMRC), has conducted research into the optimum design of interpanel-pillar, because this system may be adopted in other coal mines as well. Field measurements of the deformation of the gateroads and of stress distribution in the pillar show that the designed layout of the panel and pillar and the supporting system are proper from the viewpoints of gateroad maintenance and spontaneous combustion in the pillar.

Jan 1, 1990

By Fraser CJ

Stability control plays a prominent part in the planning and execution of coal winning in the deep open cuts in the Latrobe Valley operated by the State Electricity Commission of Victoria (SECV). Different stability mechanisms affect the individual overburden and coal faces. These are the classical rotational slip in overburden and the three-dimensional tetra- hedral wedge or planar block slip in the coal faces. The stability of the overall batters is affected by the so-called "block sliding" mechanism, which is unique in Australian open cuts. The basal stability of the open cuts is affected by pressure from water in confined aquifers underlying the coal being excavated. This paper describes each of these mechanisms and the current monitoring and con- trol techniques practised by the SECV.

Jan 1, 1982

By Ruilin Yang

Based on large amounts of field data, this paper evaluates the validity of the above equations. During the evaluation, the different selections of the frequency in the equations were examined with field data. It is found that when they are used to estimate the vector sum values the above equations could result in large deviations from the values obtained directly from the field measurements or the waveform integration. The simple equations may be used to make rough estimations for single components of blast vibration provided that appropriate safety factors are taken into account. For single component vibration, the principal frequency (from ‘zero-crossing’) seems more effective to describe the blast vibration than the dominant frequency (fron FFT) for vibration peak value estimation using the simple equations.

Jan 1, 2012

By L. W. Hamel

"Two 35 foot diameter enviro clear thickeners were tested in series as CCD units from June until October, 1978. Up to shutdown in July, we ran with automatic bed level control via the level probes and underflow pinch valves. Despite extensive efforts, we were unable to eliminate the surges created between the units by the opening and closing of the pinch valves. Early in July, the best rake speed and gap setting were determined. After shutdown, the enviro clears were run by manually controlling the pinch valves. These efforts were successful.A few mechanical problems were encountered while operating the thickeners. New units should incorporate more support for the drive coupling and a rubber feed seal. A few modifications of the instrumentation control scheme will be required before the units can be fully automated. A less sophisticated automatic flocculant addition system will accomplish the desired results. Control of the underflow withdrawal via the pinch valve should be investigated further. Our best results were obtained by keeping the feed volume to the No. 1 enviro clear constant. Surges were controlled by opening or closing both underflow valves proportionately.Capacity of the enviro clears is dependent of many variables. The ore treated during the test program was much finer than that reported on in R & D Project Report 76-02. Conditions were never steady enough to determine best flocculant dosage or addition point(s). The lowest soluble losses were obtained at very high wash rates. The underflow densities drop but the soluble losses also drop. Regression equations were developed in order to assess the effect of the various parameters. Within the range studied, these equations will predict the performance of enviro clear thickeners as CCD units on Elliot Lake ores. Our results show that the enviro clear thickeners are a viable alternative to the conventional CCD thickener."

Jan 1, 1979

Continuing with the effort of providing new and more effective exploration methods to the mining industry, where direct methods (drilling, cross-cutting, etc.) are not applicable, either for logistical or environmental reasons or because they are costly and sometimes ineffective, we present here a new seismic technique based on full wave recording of 3-D channel waves generated within the coal seam across a longwall. In the past two years we reported the application on In-Seam High Resolution Seismic Reflection (ISHRSR) and In-Seam Seismic Tomography (ISST) to map non-coal inclusions that disrupt the coal seam continuity. In the present paper we present a 3-D In-Seam Seismic Tomography (3-DTSST) method using 3-D channel waves recorded by three component high resolution geophones. The method allows to distinguish longitudinal and transversal components of the channel waves, similar to the spheroidal and toroidal modes for the free oscillations of the earth. The recording of these waves allows a more complete analysis of the free modal vibrations of channel waves, permitting a more complete inversion of the structure of the coal seam through which they travel. The full wave analysis provides additional insights of the detailed coal structure for larger, distances than for the ones previously reported using the one dimensional method. The refinement of the inversion software is also a contribution towards the better definition of the coal seam geometry and structures disturbing them such as sandstone channels, sandstone rolls, partings, mine voids, faults, fractures, etc. The method is illustrated with three case studies where subsequent mining revealed the virtues and limitations. The first example deals with the problem of mapping mine works in one side of a longwall panel which geometry is well known, to verify its applicability to map old mine works. The second example deals with a sandstone body that partially scoured the coal seam withing a longwall panel. The third shows an application of the method to map roof conditions in a longwall panel where this problem critically affected production scheduling and costs

Jan 1, 1996

By Nicolas Denies, Gust Van Lysebetten, Bart Lameire, Jan Maertens, André Vervoort, Noël Huybrechts, Flor De Cock

"Abstract Originally developed for ground improvement works, the deep mixing method (DMM) has increasingly been applied in recent years for the realization of soil and water retaining structures and as alternative to traditional foundation solutions. From practice, there is a real need for practical guidelines dealing with the execution, the design and the control of such applications. With the aim of developing such guidelines, the BBRI ‘Soil Mix’ project was initiated in 2009. Within this research project, deep soil mix (DSM) material from 38 Belgian construction sites has been tested. In spite of the large advances in the mechanical characterization of the DSM material, one major issue remains the representativeness of the typical core samples in comparison with the real scale behavior of the soil mix elements. There is among others the question of the influence of the unmixed soft soil inclusions on this behavior and the issue of the scale effect which must be considered in the design. In order to investigate these questions, 8 large scale UCS tests and 17 large scale bending tests have been performed on excavated soil mix elements. The present paper discusses results of this experimental campaign, presents some research perspectives and highlights different aspects related to the design of soil mix elements for the realization of retaining wall or foundation solution.INTRODUCTIONSince several decennia, the deep mixing method (DMM) has been used to improve the strength and deformation characteristics of weak soils. In recent years, deep mixing has increasingly been applied – in Belgium and in other countries – for the realization of soil and water retaining structures and alternative foundation concepts. With regard to the execution of the DMM, one can refer to the European standard EN 14679 on deep mixing (2005) that was elaborated under the umbrella of CEN TC 288 “Execution of special geotechnical works”. However, from practice, it has been experienced that this execution standard does not provide enough pragmatic information and guidelines, in particular for the more recent applications of the deep mixing method (with retaining and bearing functions). The same need by the sector for guidance rules linked to design aspects in the context of Eurocode 7 was experienced as well. With the aim of developing such guidelines and in order to provide feedback to the European standardization platforms, the Belgian Building Research Institute (BBRI) has initiated the BBRI ‘Soil Mix’ project (2009-2013) in collaboration with the KU Leuven and the Belgian Association of Foundation Contractors (ABEF), the Belgian branch of the EFFC. Within this research project, deep soil mix (DSM) material from 38 Belgian construction sites, with various soil conditions and for different execution processes (CVR C-mix®, TSM and CSM), has been tested (Denies et al., 2012)."

Jan 1, 2014