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Managers are demanding efficient use of their resources and part of this demand is leading to the idea of integrated audits for Occupational Health and Safety (OH&S), quality and the environment. It is possible to construct audits which test the compliance in this area with standards established by management systems and it may be that such an integrated audit of a site could reduce the time of auditing and be equally effective as three separate audits. However, this is only a maybe. To do an audit on all three aspects when they are not fully integrated results in more time wastage than doing three separate audits. But organisations are not structured around the audit process (some financial managers may query this statement). The organisational management systems are put in place to achieve the organisational goals - presumably in an efficient and cost-effective manner.

Jan 1, 1995

By P Andrieux

By 1996 ground control-related problems at Brunswick Mine had raised serious concerns regarding the safe and economical extraction of large portions of the reserves. These difficulties were mainly caused by high stress levels in pillars, instabilities resulting from wide spans supported by ageing support elements, and chronic difficulties supplying rock fill from the surface quarry to the underground workings, which resulted in many large voids remaining open for long periods of time. Significant changes have been implemented at the site since 1996, amongst which were a change of mining method, the introduction of paste backfill, the establishment of stress management measures, and the introduction of shotcrete on a large-scale. This paper focuses on the regional ground conditions associated with both the previously used primary-secondary mining method and the newly implemented pyramidal pillarless technique, as well as on some of the stress management measures implemented at the mine.

Jan 1, 2000

By R. J. Cocks

Water auditing and water efficient practices are evolving as the quantitative tools for water balance reporting in the mining and minerals processing sector. This paper was written to describe the process of water auditing in a gold mining environment. It will contribute towards building an appropriate water management framework for The Cooperative Research Centre (CRC) for sustainable resource processing (CSRP). The research assists with the assessment of water balances in mining and hydrometallurgical processes and provides, on the ground, steady-state data for ongoing probabilistic modeling underway at most of Newmont?s gold mine operations. Five Newmont case study mine sites including the Tanami Granites Goldmine are central to this PhD water project study. The function of the Tanami-Granites water audit exercise was to measure a controlled flow of various water quality types and set a framework to establish further research for water efficiencies and water conservation in mining.

Jan 1, 2009

By David Bigby

Room and pillar mining with full pillar extraction is one of the most hazardous systems of underground coal mining, a significant hazard being the potential for sudden goaf override. The Autowarning Telltale (AWTT) is a new development for pillar extraction operations, based on the well proven and simple Rockbolting Telltale safety monitoring device. It is now being applied in room and pillar coal mines in India, with significant potential for application worldwide. The Autowarning Telltale is an intrinsically safe low-cost, self-contained unit installed into the roof either during pillar development or prior to pillar extraction. It provides a highly visible warning via flashing Light Emitting Diodes (LEDs) when a preset level of roof movement has been exceeded. The paper provides a full description of the instrument and two case histories of its initial application at fully-mechanized Indian sites using the split and fender technique.

Jan 1, 2011

By Michael Gauna

Ground fall injuries and fatalities in United States underground coal mines have shown a diminishing trend. Advances in bolting and standing support systems have led to improved safety in underground coal mines. However, the Crandall Canyon Mine disaster in 2007, in which 9 individuals were fatally injured as a result of a widespread collapse, emphasized that proper mine design is a critical issue that must be addressed. The Mine Safety and Health Administration (MSHA) has instituted technical review procedures structured to facilitate the implementation of safe mine designs in underground coal mines. The technical review process and the typical information required are outlined in this paper. The range of mining situations that lead to a technical review, common design methods submitted for review, and their relevant guidelines and limitations are also discussed. Additionally, the relationship between design criteria and mine site historical experience is discussed.

Jan 1, 2011

By Nag D. K

The Dolphin Scheelite orebody is located near the old mining town of Grassy on the south-east comer of King Island in Tasmania. Surface open cut mining of the Dolphin deposit was conducted for a number of years, then the proximity of the sea and adverse stipping ratio led to underground mining. As a result of the variable orientation and dimensions of parts of the orebody a number of mining methods were practiced at the Dolphin mine until 1990 when a combination of high processing and surface site costs coupled with low tungsten prices led to the cessation of operations. In this paper the different mining methods practised are examined and critically reviewed. The more successful mining methods were developed with experience and improving equipment technology to the extent that the underground operation produced ore at the lowest unit cost during the final years of operation.

Jan 1, 1995

Over the last five years Du Pont (Australia) Ltd has developed a commercial range of new generation emulsion based explosives concurrently with the development of new explosives-placement systems. The paper outlines Du Pont's emulsion technology and history of product development from the initial emulsions (Tovex E & EL) to emulsion/ANFO blends (Tovex BE) through to the most recent development of Du Pont's SOL emulsion component. The paper also outlines the development of materials handling systems on site to load waterproof bulk explosives from the original pumper trucks through to the multipurpose agitator bowl blending and pumping units at the heart of Du Pont's SOL emulsion system currently available within Australia. The last section deals with some of the more important features of enhanced agitator bowl truck designs and outlines examples of the complete SOL emulsion system and methods of operations currently practiced at specific mines within the Bowen Basin coalfields.

Jan 1, 1986

By H. Asgari, A. G. Odeshi, J. A. Szpunar

In the present study, the dynamic response of AZ and AE cast magnesium alloys to shock loading, are compared for strain rates ranging between 900 and 1200 s-1. Texture measurements showed that after shock loading, the (00.2) basal texture component of both alloys was strengthened. However, the strengthening magnitude was higher for AE samples. Also, it was observed that the twinning fraction decreased in both alloys with increase in the amount of alloying elements. In addition, cracks are formed at the interface between matrix and second phase particles in the AZ alloys. However, crack nucleation and fracture in AE alloys occurred at the sites where twins accumulated. Furthermore, analysis of the dynamic mechanical behaviors showed that the ductility of AE grade is higher than that of AZ alloy for all strain rates used in this research. This difference was explained by differences in deformation mechanisms of these alloys.

Jan 1, 2014

By Q. F. Wang

Spontaneous combustion hazard of loose coal in the top-coal caving region of entry affects the safety of the entry and top- caving longwall face seriously. In this paper, by combining on- site temperature tests with lab tests and numerical simulation, the characteristics of microcirculation close to the top-coal caving region are analyzed. A model for the temperature fields of the microcirculation in loose coal is presented. Based on this model, the temperature distribution and possible self-ignition region can be predicted. Further, the heat and mass transfers in microcirculation are studied. Finally, the mechanism of oxygenation during the spontaneous combustion of microcirculation in loose coal of the top-coal caving region of entries is put forward. The research results in this papa may provide ideas for the prevention and putting out of the fire caused by spontaneous combustion in the caving zone.

Jan 1, 2004

By Garland Likins

The Texas Department of Transportation, now considering using Augered Cast-In-Place (ACIP) Piles (also known as Continuous-Flight-Auger or CFA Piles) in their foundations, awarded a research project to Professor Mike O'Neill at the University of Houston (UH) to study the advantages and potential difficulties with ACIP/CFA piles. ACIP/CFA piles were installed on three sites for UH; they had extra instrumentation and additional measurements by UH staff during installation which are beyond the scope of this paper. Independent visual logging of the pile was done by an experienced inspection firm. The main advantages of ACIP/CFA piles are their speed of installation and their economy. Potential savings are substantial. Disadvantages include an unknown structural condition of the shaft. Inspection is critical, but many simultaneous observations make accurate inspection difficult. Because of resulting uncertainty, many engineers have avoided ACIP/CFA piles in the past.

Jan 1, 1998

By Adrian Moore, Alan Richards

A real-time system for prediction of the effect of meteorological conditions on airblast overpressure levels has been established in the Hunter Valley Coalfield in Australia. Real-time meteorological data from continuously operating sounding equipment and a predictive meteorological model is input to an atmospheric refraction model that enables the effect of meteorology on airblast overpressure levels in the area surrounding the blast site to be evaluated. Graphical outputs from the model, which are superimposed over a scaled airphoto of the mine and surrounding area, show the extent that airblast levels will be increased. When combined with inputs that quantify the effect of blasting specifications, the airblast levels that will result in the surrounding area from the combined effect of blasting specifications is determined. The model permits those responsible for blasting to make more accurate decisions on suitable times that blasting may take place to conform with applicable airblast limits.

Jan 1, 2009

Cable bolts are being used more extensively by the mining industry for many different rock reinforcement applications. The configuration of these bolts has evolved over the last 20 years to meet the immediate needs of industry at the particular time. Most improvements to date have focussed on increasing the mechanical performance with little attention given to issues such as ease of handling, matching response to that of the rock mass or corrosion protection. Ultrastrand has been designed and being developed with this broad perspective in mind so that it will satisfy the ground reinforcement needs of today's and tomorrow's mining industry.Laboratory tests on Ultrastrand prototypes have confirmed that mechanical performance is superior or equivalent to Standard and Birdcage Strand respectively. Preliminary discussions have been held with an installation equipment manufacturer with a view to conducting a trial at a mine site by early-1992.

Jan 1, 1992

Most types of nuclear power reactors use uranium dioxide fuel. Power reactors using natural uranium dioxide'fuel are of special interest to countries such as Australia that have their own uranium supplies. A wide range of uranium dioxide powders can be fabricated and the ideal one flows readily, presses without the need for binders or lubricants, sinters to the required density and gives low reject rates at all fabrication stages. Sinterable uranium dioxide is usually produced via the ammonium diuranate route. The A.A.E.C. is aiming to demonstrate production of nuclear grade uranium dioxide from Australian concentrates, improving technology where possible. Details are given of the dissolution, solvent extraction, precipitation, filtration, drying, and calcination-reduction steps. Solvent extraction from sulphate media is also under study with a view to developing a process to produce a nuclear grade product at the mine treatment plant site,

Jan 1, 1969

By Paul Clayton

Case Study ? Site: BMA Saragi Coal Mine Queensland Australia ? Model: Marion 8050 ? YOM: Mid 1970s ? Boom: 97M ? Bucket: Original capacity of 100 Tonnes upgraded to 125 tonnes at time of filtration upgrade. ? Apps: Swing, Hoist & Drag Gearboxes ? Oil: Oil Castrol Alpha TT1200 Viscosity of 1208 cSt @ 40° C (104° F) 720ltr Oil Volume Trial and Installation Justifications ? To reduce gearbox overhauls. Typical schedule being 5 years. ? Bucket upgrade from 100 tonnes to 125 tonnes. Increased gearbox demand and stress. ? Increase of overhauls out to 10 years + ? Saving per Dragline estimated to be US$8-10M in downtime and maintenance if successful. ? In compliance with BHPBilliton Global Maintenance FLAC program ? Fuels, Lubricants, Air and Coolants ? Cost Justification ? Downtime: 4 days ? Lost production: $420,000 ? Cost of parts: $162,000 ? Labour and misc: $41,000 Gearbox failure cost $623,000

May 1, 2008

By H. Kenyon Burch

PaQe Introduction.............................................................. 708 Plant Sites................................................................ 709 Type of Construction...................................................... 710 Mine Plant............................................................... 710 Dual Arrangement.................................................... 711 Underground Haulage............................................. 711 Tipples........................................................... 712 Underground Pockets............................................. 712 Automatic Measuring and Loading Devices......................... 712 Shafts ............................................................. 716 Ore and Spillage Skips............................................ 716 Automatic Hoists................................................. 716 Man Elevator..................................................... 717 Crushing Plant....................................................... 718 Storage Bin........................................................... 720 Sampling Plant....................................................... 720 Motors and Other Equipment.......................................... 721 Compressor Equipment................................................ 721 Concentrator............................................................. 722 600-Ton Test Mill..................................................... 722 The 15,OO0-Ton Concentrator...................................... 726 Grinding Section.................................................. 726 Floor Arrangement........................................... 726 Marcy Ball Mills............................................. 729 Performance of Crushing Machines............................ 730 Flotation Section.................................................. 780 . Flow-Sheet with Callow Flotation Cells....................... 731 Flow-Sheet with the Inspiration Flotation hfachines............. 731 Flotation Air Supply.......................................... 733 Concentrates Filter Plant.......................................... 733 Drag Classifiers................................................... 733 Tailing Settling System........................................... 735 200-Ft. Dorr Thickener ...................................... 736 General Equipment and Supplies.......................................... 737 Water Supply......................................................... 737 Power Supply......................................................... 737 Transformer Stations.................................................. 738 Shops and Railroad Facilities.......................................... 739 Conclusion................................................................ 740

Jan 1, 1917

By Andy Ingriselli, Andrew Famiglietti, John Westland, Greg Landry

Atlas Dewatering was contracted to install and maintain a groundwater control system for the new Bessarion Subway Station and the Tail Track Structure on the Toronto Transit Commission’s new Sheppard Subway Line. Atlas met the challenges presented by the project by closely reviewing the contract documentation provided by the Program Geotechnical Consultant, Golder Associates and by working with the general contractors, Bondfield Construction Company and PCL Constructors Eastern, inc., throughout the duration of both projects. In addition to concerns about soil loss, excessive settlement and seepage, the consultant was concerned about spreading hydrocarbon-contaminated groundwater between the two aquifers present at the Bessarion Station site. By installing a system of multi-level vacuum eductor wells around the perimeter of the excavation, Atlas was not only able to provide a dry excavation for construction, but, due to a unique well design was also able to prevent cross-contamination of the aquifers.

Jan 1, 2001

By Patrick J. C. Ryall

Remotely control led drills capable of being lowered to the sea-floor from ordinary research vessels have been developed over the past two decades. These drills are currently being used in geological survey programmes on the continental shelves (Canada, Japan, Norway, United Kingdom) and for studies of mid-ocean ridges. Generally the drills fall into two categories: 1) those which are powered from the surface and controlled by an operator, and 2) those which are battery powered and follow an automatic programme. Some drills have a television camera mounted on them sending a picture to the surface as an aid to site selection and geological interpretation. Typically the drills are capable of drilling a core 2.5 - 5 cm diameter up to 10 m long. While most of these drills are designed for <1000 m depth, some can drill in water depths of as much as 3500 m.

Jan 1, 1985

By Michael Kelly

Longwall mining is the principal method of underground coal mining in Australia, with 70 million tonnes being produced by longwall mines in 1999. However, the mechanisms that control longwall geomechanics are still not clearly understood resulting in stoppages costing several hundred million dollars per annum The CSIRO has been investigating longwall geomechanics with consultant groups and minesites through several ACARP supported projects since 1994. The research has aimed to improve longwall support design and control methods by defining strata failure mechanisms and their occurrence about underground extraction panels, It also aimed to develop better predictive tools bur a broad range of underground environments. As a result of site studies at more than 8 locations some of the aspects that have been touted to control longwall geomechanics, especially from a 3D aspect are highlighted. These aspects include stress controls, geometry, faulting, depth. longwall width and changes in lithology.

Jan 1, 2000

By A. W. Khair

This paper presents an analysis of ground movements recorded from longwall operations in the Northern Appalachian region in West Virginia. The site chosen for the investigation was selected due to varying heights of overburden and topography and was instrumented for both surface and subsurface measurements. The instrumentation areas consisted of two panels covering various sections with unique geologic and topographic features. Instrumentation included surveying monuments and shallow boreholes using an inclinometer for measuring horizontal strata displacements. Vertical strata deformation was monitored utilizing a unique design of the mechanical grouting method. Full length borehole profile extension was measured using Sondex displacement rings in the inclinometer installation. Subsurface displacements, i. e. caving zone, fractured zone, and highly deformed non-fractured zone were identified. The nature of surface disturbances with respect to varying geologic settings were compared, and an attempt was made to simulate final strata caving and bed separation using finite element analysis.

Jan 1, 1987

Backfil ling of excavated Sub Level Open Stopes has been underway since March 1989 and as at December 1992 some 1 100 000 cubic metres of Cemented Aggregate Fill have been placed. During these three years significant developments in fill quantities, types and cost have taken place.Operational improvements have reduced the quantity of Cement Aggregate Fill by 40 per cent. These results have been achieved by:ò rescheduling stopes,ò designing smaller primary stope, and ò use of uncemented rockfill.Unit cost for Cement Aggregate Fill have fallen in the order of 50 per cent through:improving fill hole reli ability,simplified barricade construction procedures, reducing the cement content,ò substituting dune sand for deslimed mill tailings, ò improved maintenance at the Backfill plant, and ò renegotiated site freight agreement.This paper will review the historical developments of backfill use at Olympic Dam.

Jan 1, 1993