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he Wyalong goldfields were discovered in September, 1893, Messrs. Neeld and Sons, owners of the principal mine, being the pioneer prospectors. During the earliest days of the field the ore was sent to Barmedman, a distance of eighteen miles, for treatment at a battery there. The field rapidly increased in importance, and it was not long before a public battery was established on the spot. After some considerable quantity of ore was treated by this process, it became apparent that battery treatment was quite unsuitable for the richer ores, involving, as it did, considerable loss in the tailings. Recognition of this fact led to the erection, in 1895, of plants by the Wyalong Chlorination and Cyanide Works, owned by Mr. Walter Sully, for treatment by their processes; followed, at a later date, by Messrs. Neeld and Sons Chlorination Works. The Wyalong Chlorination and Cyanide Works, after a delay of twelve months in the erection of their plants, have since catered continuously up to the present time for the requirements of the field.Their plant consists of a No. 3 Gates' rock·breaker, a revolving dryer, a No. 5 Krupp mill, revolving roasting furnace with finishing hearth, two chlorination vats of 20 tons capacity each, "nine cyanide vats of 30 to 100 tons capacity, two Wheeler pans and three chlorine generators. The ores are purchased outright on assay at a fixed scale of charges, and treated by the owner of the works on his own account.

Jan 1, 1903

By Donald F. Reed

Deposits of gray hematite occur in two districts in Talladega County, Ala., the Emauhee-Tallasechatch and Weewoka, both in the; vicinity of Wintorboro, 50 miles east of Birmingham. The deposits were investigated by the Bureau of Mines in 1945 and 1944. Approximately 15,000 feet of diamond drilling was done and 6,000 linear feet of trenches excavated and sampled.

Jan 1, 1949

By W. Barnett

The Limpopo Metamorphic Belt is a complex geological terrane with at least three major deformational events. Tectonically juxtaposed lithology, open to isoclinal folding, crosscutting and re-activated shear zones and metamorphic gneisses and schists make pit slope design and maintenance a risky business. Venetia diamond mine?s Cut 3 is planned to reach 360 m by 2011. The difficult rockmass created problems in the original pit and a new more comprehensive slope design was necessary. Nearly 9 km of geotechnical drilling were undertaken to produce a new geological model and provide geotechnical information near the final Cut 3 face. All existing data from the pit were brought together into a database. SRK Consulting were brought into the project to audit the process and provide most of the manpower for the data analysis. Existing failures were back-analysed and the geotechnical domains identified. Analyses of only the southern domains are discussed in this paper. Geotechnical engineers can design slopes at any angle, but it is up to the managers at the mine to decide what risk they are willing to accept in a slope design. Once the issue of risk was discussed and settled in respect of the consequences of failure, each of the main geotechnical domains were analysed to produce a slope design at5% probability of failure with 15% above the first ramp. A risk assessment of the design was then undertaken to determine what risk the design placed on the equipment, personnel and the profitability of the overall mining operation. The risk assessment indicated minimal risk to the operation. One of the main assumptions of the final design is that the pit slopes will be dewatered. A project was immediately put in place to determine a groundwater model for the mine and to thereby determine the best dewatering procedure. However, it should be obvious that it is practically impossible to prevent benches from getting briefly saturated with water during storm conditions. It was therefore necessary to look specifically at supporting the crests of the ramps in the problematic southern domains to guard against the possibility of crest failure during heavy rains. The data available were re-analysed toward this objective. Spiles were recommended as the most cost-effective support system, and a probabilistic approach was used in the design. The final design has a 5% probability of failure, and the analyses indicate a strong sensitivity of the required spile spacing to the strength of the reinforcement material that will eventually be used. The pit slope parameters derived as per the discussion in this paper have just begun to be implemented at Venetia Mine.

Jan 1, 2001

By A. Z. Toper

This is a sampling of the papers presented at the conference, the proceedings can be bought from the SAIMM An extensive research programme to address the issue of rockburst control has been undertaken over a number of years. This paper discusses the development of preconditioning techniques to control face bursts, for safer mining in seismically hazardous areas. Preconditioning involves regularly setting off carefully tailored blasts in the fractured rock immediately ahead of a mining face, so as to encourage slip on pre-existing fractures, in order not to allow the accumulation of high strain energy density in the rock mass. Two different preconditioning techniques have been developed, namely face-perpendicular preconditioning and face-parallel preconditioning. Both have prevented face bursting in areas to which they have been applied, even though several large seismic events have occurred close to the faces in some areas. In addition, minimal overall damage was observed in the preconditioned panels following these events, compared to similarly exposed unpreconditioned panels. Preconditioning has also provided some protection to the face area from distant events, through the capacity of the preconditioned ground to absorb energy. An improvement in hangingwall stability and productivity has also been noted in preconditioned areas. In order to determine the optimum blast parameters for achieving the most effective preconditioning, an extensive optimization study was carried out for the face-perpendicular preconditioning technique. While optimum values for parameters such as hole length, diameter and spacing were determined, it was ultimately concluded that the differences in results obtained by varying the preconditioning parameters were less significant than the clear positive differences observed when comparing preconditioned areas with non-preconditioned areas.

Jan 1, 2000

By D. Strachan

Installation of support in known poor ground intersections during reaming operations requires rapid access to stabilize the shaft wall and thus to prevent the loss of the shaft through scaling. This is especially relevant to shafts of long dimension where the duration from time of exposure to time of support installation is lengthy This paper deals with the innovative methodology employed at Harmony?s No. 8 Shaft 17/24 level sub ventilation shaft to rapidly support a shale intersection between 23 and 24 Level by employing a single deck stage suspended from the reamer head by means of Skyjack winches.

Jan 1, 2009

By R. Bitmead, R Barker, A. Drake

The opencut coal mine is located about 50 km west of Brisbane, the capital city of Queensland in Australia and produces about 140 000 tonnes per annum of high grade steaming coal utilising a small team (ten) of personnel to mine remnants of the Aberdare and Bluff seams left by previous underground mining. This, in itself, is not remarkable except that one of the seams has commenced spontaneously cornbusting resulting in temperatures in excess of 55’C commonly being encountered with portions of the p’it being wreathed in steam. To extend mine life, the mine required a blasting system that would: . Safely blast in temperatures below 100°C . Significantly reduce overall unit costs . Not increase the current vibration impacts on nearby housing . Not increase flyrock.

Jan 1, 2002

By Patterson J. H

An infra-red absorption study has been made of crocidolite, country rock. and associated host rocks from Wittenoom Gorge. The spectrum of the country rock is appreciably different from those of crocidolite and the magnetite-rich host rocks which are closely similar. A process to separate crocidolite-bearing ore from country rock based on infra-red emission is therefore possible in theory.

Jan 1, 1966

By Hans Hamrin

Three drill-blast cycles of 3.1 m advance achieved in one working shift of 7.5 hours at the Holsfjorden Tunnel project in Norway. The tunnel, 5235 m long, with a cross section of 8.6 m2, was completed several months ahead of schedule. This remarkable performance was achieved by a crew of 16 men, using machines specially designed for small tunnel excavation. The integration of drilling and charging into one unit, mucking and transport in another, reduced non-productive time considerably. The average cycle time of 140 min made it possible to complete three rounds in one 7.5 hours shift.

Jan 1, 1987

By M. J. Raffaldi, K. W. Harris, K. A. Perry

"Highwall miners have been widely used to extract additional coal reserves from existing surface operations, particularly on contour operations in the Appalachian coalfields. Using a continuous miner cutting head, coal may be extracted from significant depths (such as 150 m), leaving behind an array of web and barrier pillars with the purpose of maintaining highwall stability. This method inherently involves elevated risks to both equipment and personnel due to proximity to and increased exposure time near highwalls. As a result, modern operations should actively design web and barrier pillars to maximize extraction while providing adequate stability. The ARMPS-HWM software, an empirical-based program created for the design of web and barrier pillars at highwall mining operations, is one such approach. The calculated stability factor is compared with empirically established guidelines produced from examining case histories.The ARMPS-HWM program is a handy tool for initial design, but understanding the site’s structurally significant geologic features and geomechanical behavior is important and may potentially increase extraction. We created a two-dimensional numerical model using FLAC3D and calibrated it to ensure pillar strength, closely following the Mark- Bieniawski formula for a typical range of pillar geometries and overburden properties. The development of pillar stresses along a highwall panel was then numerically investigated as mining progressed, and the stress distribution between barrier pillars was found to be asymmetric, which can result in an over-design of the closeout web pillars if tributary area loading is assumed. Finally, the importance of adequate barrier pillar stability is highlighted."

Jan 1, 2014

By Randy R. Williams, Roberto R. Olivera, Brian W. Wilson, Marina S. W. Li

"An extensive, deep mixing (DM) ground improvement program using the Cutter Soil Mixing (CSM) technique was designed and constructed in 2013 to support up to 20 m (66 ft) high Mechanically Stabilized Earth (MSE) walls and bulk earthworks for the development of the Kitimat Liquefied Natural Gas (LNG) facility at Bish Cove, British Columbia. The deep mixing program consisted of overlapping rectangular panels of in situ cement treated soils, constructed using the CSM technique, to form barrettes covering an area of approximately 12,900 m2 (15,428 yd2) and providing suitable static and seismic stability of foundation soils for support of the proposed MSE walls, which would in turn support LNG facilities. The deep mixing program comprised of 1645 CSM panels that were constructed through varying thicknesses and discontinuous layers of very soft fine-grained marine deposits and/or loose sandy silt to silty sand deposits, embedding typically 2 m ( 6.6 ft) into dense silty sand to sand and gravel. CSM panel depths ranged from 5 m (16 ft) to 30 m (98 ft) and were constructed by treating approximately 73,900 m3 (96,658 yd3) of soil yielding average unconfined compressive strengths exceeding 2.5MPa (363 psi).This paper outlines the approach adopted for the design of the CSM ground improvement program in the highly variable subsurface conditions present at the site. A phased sitespecific investigation consisting of boreholes, test pits, Cone Penetration Tests, piston tube sampling, advanced laboratory testing and groundwater monitoring was implemented. In addition, soil-cement bench scale testing was completed, followed by installation of 8 CSM panels for field trial purposes. Extensive geotechnical static and seismic analyses including Limit Equilibrium stability analyses, liquefaction assessments, and advanced numerical modeling were undertaken to optimize the design and meet the project-specific design performance criteria. The Design-Build team worked closely to develop and implement Quality Assurance and Quality Control plans and managed significant construction challenges while achieving suitable panel termination depths."

Jan 1, 2017

By Richard E. Gray

The Office of Surface Mining Reclamation and Enforcement (OSM) is preparing an Abandoned Mined Lands Reclamation Control Technology Hand- book. (l) GAI Consultants, Inc. , recently prepared Chapter 2 on Mine Subsidence Control which contains a summary of subsidence abatement measures plus two new decision matrices for evaluating the subsidence abatement options that might be considered for a particular problem. These decision matrices are presented for information. Review of the subsidence abatement methods resulted in identification of items where research may impact the current state of technology in mine subsidence control. These research needs are presented to stimulate discussion of their importance in subsidence abatement and to encourage funding agencies, researchers, and practitioners to work on them.

Jan 1, 1982

By T. Bajpayee, J. Ellenberger

Microseismic monitoring and evaluation is one aspect of the National Institute for Occupational Safety and Health (NIOSH) research program. Roof falls are often preceded by a period of elevated microseismic activity, but not all periods of elevated activity result in a roof fall, nor do all roof falls occur after some amount of elevated activity. The objective of this study is to review periods of elevated microseismic activity and determine whether fracture activity rate can be used to anticipate the initiation of roof falls. The study was carried out at an underground limestone mine where major roof falls are associated with excessive horizontal stress. The progression of roof falls was detected by the microseismic signature produced by the rock falling from the mine roof onto the mine floor, which is termed a roof fall impact event. A total of nine elevated fracture activity periods that resulted in seven major roof falls were examined. It was observed that elevated fracture activity preceded the initial roof fall impact event in three out of four major roof falls. The initial impact event was not identified for the remaining three roof falls. Fracture event rates were analyzed and a roof fall alarm trigger of five fracture events in a ten minute time period was established for this test case. The fall alarm trigger was tested against six of the elevated activity periods. Four roof falls occurred in the six periods of elevated activity, and two would have triggered the alarm before the roof fall occurred, while two false alarms were generated. The results show that limited success would have been achieved by the microseismic system as a roof fall alarm trigger. However, the trigger would have been successful at warning of the onset of elevated activity, allowing mine employees to respond appropriately. The study highlighted some issues with implementing such a system in an operating mine, including the need for real time identification of fracture related microseismic signals among mining induced signals, and accurate location and identification of fracture clustering.

By R Tom Watts

The blasting industry has changed more in the last five years than in any period to date. The equipment utilized to load boreholes has changed in response to more precise blasting products and programs, and the need to maintain tighter control over product formulations produced by bulk loading equipment. Tread Corporation has built over 1,300 heavy ANFO type bulk loading units currently operating in over 40 countries worldwide. These units have been designed to meet almost every possible loading scenario but there are always new situations that require special designs and configurations to meet the challenge. The focus of this presentation is to make you aware of the process that should be used to determine the equipment best suited for your application. We will discuss loading cycle times, delivery rates, multiple product mixing capability, capacities, manpower utilization, regulatory compliance, and where and when to use automation in the loading process. We will also discuss the suitability of chassis with regard to ground pressure, turning radius, terrain, weather conditions as well as highway suitability. The US Bridge Law as well as laws that cover the concept of axle loading and spacing will be covered. Through new computer aided design and modular design capabilities, you can now have almost any configuration required to meet your bulk loading objectives. We will also review the range of equipment currently available in the market place and discuss tradeoffs between price, capacity, and complexity.

Jan 1, 2000

By John C. Machisak

THIS PUBLICATION presents injury experience and employment data for the nonmetal mining industry in the United States for 1960. Data for the mines and mills are presented separately, as shown in the list of tables. The Bureau of Mines is authorized to send questionnaires to the nonmetal mining industry for their voluntary submission of injury and employment data. As the information submitted contributes largely to the promotion of safety in the industry, special effort has been made to make these questionnaires as complete as possible.

Jan 1, 1963

By Albert Wraith, Thomas Price, Wayne Boyd, Skip (I. E. ) Hills, Cameron Harris

Most Peirce-Smith converters inject air through tuyeres, with nitrogen representing the majority of gas passing through the process. The nitrogen controls the temperature of the vessel by carrying away heat from the reactions, both globally and locally at the tuyere tip. However, nitrogen adds energy to the bath and contributes to splashing and limits the blowing rate. High oxygen smelting has made streams of gas containing high concentrations of sulphur dioxide commonplace, which can be used to substitute SO2 for nitrogen and drastically changes Peirce- Smith converting (and all other smelting/converting processes as well). Less SO2 is required to carry away the same quantity of heat, which allows higher concentrations of oxygen and leads to the possibility of increased production. The paper investigates this substitution, its impact on converter productivity, and on the remainder of the plant. 181

Jan 1, 2009

This paper reviews the manpower requirements of the Australian mining industry. It has been necessary to provide general background information in order to support the view that university education in mining and mineral process engineering should be strengthened rapidly in Australia to provide graduates for the industry.

Jan 1, 1969

By Paul S. Goodman

Volume I This report presents the first national survey of miners' attitudes and opinions about their-work. The goal is to present attitudinal data that bears on coal production. Interviews were conducted in 26 mines with 2,000 miners. High levels of cooperation were exhibited by management, union and the employees. Data are presented about miners' attitudes about general aspects of their work such as pay, supervision, their jobs, etc. Another section of this report reviews opinions about specific aspects of work performance. Recommendations are presented.

Jan 1, 1985

By Alastair C. Torrance

"A brief review of the Australian mining industry is given followed by a more detailed treatment of a study of the influence of primer Size on explosive performance. This is based on a joint research programme conducted by BHP Central Research Laboratories and Dyno Wesfarmers Ltd and examined the effect of the size of cast primers on the run up and steady state detonation velocitiesof ammonium nitrate based explosives as a function of blasthole diameter. The field trials examined a numter of the Dynamo 'Westfarmers HDF series of primers in conjunction with ANFO, emulsion and watergel explosives. Results indicate that the iun up velocity of 187 mm diameter ANFO charges is negligible using cast primers as small as 150g. However, emulsion and watergel explosives did exhibit run up in both 187 and 3:1mm diameter blastholes, independent of the size of primer. This could last from 7 to 10 blashole diameters"

Jan 1, 1991

This report summarizes the results of the Narragansett Win Projec't's activities during the U.S. Bureau of Mines (BOM) Phase 1, which was transitional from and which followed the National Science Foundation (NSF) Phase which initiated the investigation of New England's potential roil resource. The 960 sq. mile basin is structural and topographic lowland containing 12,000 to 20,000 ft. of terrigenous clastic sediments of late Pennsylvanian age, and which rests on an upper Precambrian and Cambrian basement. The Rhode Island Formation, which is the coal-bearing unit, comprising the bulk of the Pennsylvanian rocks consists, in order of decreasing abundance, of sandstone, conglomerate, silts tone, shale, and coal. In the NSF Phase, 24 drill-holes yielded 17,900 ft, of core; in the BOM Phase I study, 4 drillholes yielded 2,100 ft. of core. Anthracite and semi-anthracite was encountered in beds Up to 30 ft. thick in widely spaced parts of the Basin. The coal, typically very low in sulfur, and a high ash anthracite, won mined in substantial volumes from 1808 to 1959 from shaft and open lit in Portsmouth and Cranston, R.I., and in lesser volumes in Mansfield, Mass. Currently coal is now being mined in Plainville, Mass. as a fuel in the manufacturing of light-weight aggregate from the same quarry that serves as the source of the rock being processed. The structurally complex Narragansett Basin is now known to have a greater extent than earlier since recent drilling by others (Chapter 2) has confirmed our interpretation that the Basin extended offshore south A Boston. The, Basin also extends into Rhode Island Sound to the south. The geological structure is more complex in the southern part of the Basin than in the northern part. Three episodes of folding have been documented on Aquidneck Island and four episodes of faulting have been demonstrated for the Basin as a whole. Relatively less well exposed rock in the northern part of the Basin, increases the difficulty of recognizing and correlating structural episodes in the northern part of the Basin. The Basin his hewn subdivided into six structural domains which appear to have distinctive structural, metamorphic, paleontological and sedimentological differences that mw assist in isolating important events in the evolution of the Basin and its component parts. The tentative structural model recently developed in POP Phase I has important implications for exploration and mining. In the first and second folding stages the coal is mobilized and thickened in the crests and troughs of folds whose axes are horizontal to subhorizontal. While conventional coal exploration and mining methods are not applicable, great thickening in the crests and troughs of large scale structures, which can he defined by geology, geophysics and drilling, may provide compensating advantages. Bedrock over most of the Basin is 0-50 ft., but thicknesses of glacial deposits up to 150 ft. are present locally. Pro-Pleistocene topographic trends are controlled by structure and rock hardness; Pleistocene deposits aligned to the S. F. are superimposed on earlier trends. The southern part of the Basin is mainly dominated by high grade Barrovian metamorphism and plutonism of Permian age, related to the Alleghanian Orogeny. About 300 sq. miles of the 960 sq. mile Basin has been affected. The remaining 660 sq. miles, in the chlorite and subchlorite zones of metamorphism are compatible with the presence of high quality anthracite and semi-anthracite. Illite crystallinity studies begun in the NSF Phase, have been carried out in the BOM Phase l with important results. About ME of the northern Basin is now known to be in the diagenetic (unmetamorphosed) or subchlorite zone and the remainder in the chlorite zone of metamorphism. Mite studies, probably best recording temperature effects, show a generally progressive increase from the NW corner of the Basin near Plainville, Mass. toward the south and southeast. Reflectivity and coal petrography studies, probably best recording pressure and effects related to shearing, indicate a generally opposite pattern. Thus these methods provide powerful tools for the ultimate solution of problems important to coal exploration for coals of higher combustible volatile content and exploitation of these. Due to the complex nature of the coal, chemical data may not he easily used to determine rank. The coals have been tectonically deformed and mineralized. This deformation plus thermal metamorphism have altered the coals, in some cases by producing natural coke. Brecciated coal is often coated with a secondary depositional carbon. The coals' hydroscopic nature and high ash contents are due to the deformed nature of the coal and the presence of this secondary carbon. The stratigraphy and sedimentology of the coal-bearing Rhode Island Formation is similar to described alluvial fan deposits. The non-geological studies al-low three conclusions to be made: 1. A substantial number of areas have been identified in the Narragansett Basin in which mining could be carried out without undue difficulty from a land use point of view. 2. Substantially more than two hundred instances of past or current- mining activities have been identified in the Basin. Many of those are in areas defined as geologically interesting, and may be advantageous From the point of view of future exploration. 3. The map synthesis technique developed for this contract is successful and may easily be adapted to future exploration in its current form and also in its expandable form dealing with unit measurements of one-tenth mile. We recommend that BOM Phase 2 exploration should accomplish the intent of the Congressional language in House Report No. 95-1251, to continue a substantial drilling and geophysics program: "The Committee expects the Bureau to continue studies involved in ascertaining the extent and quality of low sulfur coal reserves in the Narragansett Basin in New England including necessary drilling and geophysical studies. The knowledge of the extent of such deposits is of great importance to this 'energy pour' area".

Jan 1, 1979

By Luis Vassallo

El presente trabajo señala los beneficios que pueden obtenerse de la adopción inteligente de una estrategia de colaboración electrónica que responda a las necesidades de este segmento y que proporcione soluciones de verdadero valor agregado. Así, el modelo monolítico que prevaleció por muchos años, donde cada empresa era propietaria de las licencias mineras, operadora, mantenedora, contratista, vendedora, embarcadora y financiera, está desapareciendo. En la cadena de valor del proceso minero intervienen más empresas, contribuyendo valores agregados específicos y especializando funciones. Este cambio demanda mayores flexibilidades de los sistemas de información que deben ser totalmente abiertos, y permitir el intercambio instantáneo de información que facilite reaccionar oportunamente a las diferentes variables de la operación. Por ello, la colaboración electrónica permite a la minería adaptarse a un mundo que está cambiando.

Aug 25, 2002