Search Documents

By M. G. Lipsett

"The Mining Information Technology User Group considers information to be a strategic enabler to improved business performance in mining. This ad hoc group has been meeting since 2000 to share knowledge and leverage their efforts in effectively using IT in mining. In this paper, core issues to mining IT are reviewed, along with initiatives to engage industry professionals and decision-makers in the potential for improved use of information in their operations. Relevance of IT to Canadian MiningMining operations always drive to improve their performance, and so far they have succeeded by using different technologies. While economies of scale have come in fragmentation and material handling, and energy usage has improved through conservation and design of integrated mineral processing plants, these systems have the net result of tightening operational constraints, through reduced excess capacity. There are higher opportunity costs of lost production when integrated, large-scale systems are operating in a sub-optimal way.The problem is that it is profoundly difficult to run a mine in an optimal way. Optimization requires a defined objective function (e.g., profit), which is hard to pose, let alone solve, because so many inter-related aspects of an operation affect the bottom line. Even for a small, well-defined process state, it is difficult to measure all the pertinent information with sufficient accuracy to ensure that the system is performing well in real time.The art of mining remains making good decisions with uncertainty: in the orebody delineation; in the allocation of resources; in the efficiency of the operation; in the reliability of components and systems; and in responding to the downstream market. As well, individual decision-makers need to know how their decisions affect other processes and systems, so that improvements in one part of an operation do not result in such degraded performance in the rest of the plant that overall profitability goes down."

Jan 1, 2003

By C. M. Clapperton, K. E. Darke, A. J. Boyce, C. M. Rice, S. D. Redwood

"Abstract - The Kori Kollo gold deposit is hosted by a c.15 Ma sericitized dacite stock in the La Joya district on the Bolivian Altiplano. The mineralization is of the Bolivian polymetallic vein (BPV) type, with a significant amount of the gold reserves contained in the oxide cap. Field and microscopic studies, K-Ar dating, ??34S values of pyrite, alunite and jarosite, and ??18O values of alunite and jarosite demonstrate that some of this gold is supergene. Two types of supergene gold are present: minute gold grains, 1 to 10 microns across, of high fineness and associated with jarosite and iron oxy-hydroxides; and ‘invisible’ gold, which is probably sorbed onto minerals such as jarosite and iron oxy-hydroxides.Pyrite ??34S values fall in the limited range -3.5 ± 0.6‰, consistent with a magmatic origin. Sulfate ??34S values are homogeneous and overlap closely with those of pyrite (-1.2 ± 2.1‰), which supports petrographic evidence that sulfates replaced pyrite. By contrast, sulfate ??18O values are inhomogeneous with a large range (alunite +2 to 26‰, jarosite -5 to +18‰). These data are interpreted as reflecting kinetically controlled reactions involving various proportions of atmospheric oxygen and local meteoric water. This is typical of supergene alteration and is due to the seasonally dry climate of the Altiplano.The oxide-zone mineralogy is dominated by sulfates and iron oxy-hydroxide minerals with some phosphates and halides, which indicates that the groundwaters were acidic, oxidizing and relatively saline. Under these conditions the most likely complexes responsible for gold mobilization are halides.Geological data and K-Ar ages indicate that oxidation of the BPV deposits began at least around 11 Ma and possibly up to 15 Ma ago, and that supergene alteration lasted until around 4 Ma. During this period, erosion was minimal. Although supergene processes have been active on the Bolivian Altiplano since the Middle Miocene, in contrast to Northern Chile, enrichment of gold has not occurred."

Jan 1, 1997

By C. M. Clapperton, K. E. Darke, A. J. Boyce, C. M. Rice, S. D. Redwood

"The Kori Kollo gold deposit is hosted by a c.15 Ma sericitized dacite stock in the LaJoya district on the Bolivian Altiplano. The mineralization is of the Bolivian polymetallic vein(BPV) type, with a signi?cant amount of the gold reserves contained in the oxide cap.Field and microscopic studies, K-Ar dating, ??34S values of pyrite, alunite and jarosite, and ??18O values of alunite and jarosite demonstrate that some of this gold is supergene. Two types of supergene gold are present: minute gold grains, 1 to 10 microns across, of high fineness and associated with jarosite and iron oxy-hydroxides; and ‘invisible’ gold, which is probably sorbed onto minerals such as jarosite and iron oxy-hydroxides.Pyrite ??34S values fall in the limited range -3.5 ± 0.6‰, consistent with a magmatic origin. Sulfate ??34S values are homogeneous and overlap closely with those of pyrite (-1.2 ± 2.1‰), which supports petrographic evidence that sulfates replaced pyrite. By contrast, sulfate ??18O values are inhomogeneous with a large range (alunite +2 to 26‰, jarosite -5 to +18‰). These data are interpreted as reflecting kinetically controlled reactions involving various proportions of atmospheric oxygen and local meteoric water. This is typical of supergene alteration and is due to the seasonally dry climate of the Altiplano.The oxide-zone mineralogy is dominated by sulfates and iron oxy-hydroxide minerals with some phosphates and halides, which indicates that the groundwaters were acidic, oxidizing and relatively saline. Under these conditions the most likely complexes responsible for gold mobilization are halides.Geological data and K-Ar ages indicate that oxidation of the BPV deposits began at least around 11 Ma and possibly up to 15 Ma ago, and that supergene alteration lasted until around 4 Ma. During this period, erosion was minimal. Although supergene processes have been active on the Bolivian Altiplano since the Middle Miocene, in contrast to Northern Chile, enrichment of gold has not occurred."

Jan 1, 1997

By Abani R. Samal

The Fe assay values from the diamond drill-holes within a magnetite deposit of magmatic origin are utilized in this study. Only assay data from the unoxidized magnetite mineralization was utilized. The data from the overlying hematite mineralization zone was not used. A threedimensional block model estimated using ordinary kriging (OK) is used for analysis purposes. To estimate the non-linear standard deviations (s) and the confidence intervals (CI) of block estimates a discrete Gaussian variogram model is used in this project. The change-of support coefficient (rv) and the block-support correction are used in the ?block-anamorphosis?. A new calculated value of rv is 0.7283, implies that its influence in the block-anamorphosis is not significant. The CIs are calculated from the block-gaussian variables; then back transformed to the raw values. At 95% probability, the CI for the kriged block estimates of Fe values are calculated using Gaussian kriged estimates of the Fe and the corresponding standard deviations (Gaussian). The results indicate that the block estimates with a high influence from relatively small amount of samples can be identified as high-risk estimates.

Oct 1, 2009

By Elizabeth Wademan

Recessions Eventually End ??Companies aggressively cutting production and inventories ??these will come in-line with demand ??U.S. home inventories are declining ??Housing becoming more affordable ??Global trade recovering after collapsing ??Lower oil prices should act as a stimulus Protracted Deleveraging Process Beginning ??Era of leverage-driven consumption is over ??Greatest destruction of consumer wealth since WWII ??Consumers will no longer be able to substitute capital gains for savings ??Shift towards savings will be a headwind to economic growth ???Paradox of Thrift?

May 1, 2009

By Bryon Bisiaux, Walter Valery, Sonny Mwansa, George Amonoo, Adrian Dance

"Newmont Ghana Gold Limited’s Ahafo operation have been working with Metso Process Technology & Innovation (PTI) since early 2009 to increase mill throughput from a combination of controlled blasting practices and optimised primary crusher and grinding circuit conditions. For such Mineto-Mill projects, PTI’s methodology is termed Process Integration & Optimisation (PIO).Ahafo operate a SAG mill, ball mill and pebble crusher (SABC) circuit that processes a range of primary ore of varying hardness from different pits which is blended with soft oxide material. The PTI study focussed on ball mill limited material from the Apensu open pit.Following a benchmarking study of all blasting, crushing and grinding practices in January 2009, PTI recommended changes in both blasting and crushing conditions in order to generate a finer feed size to the SAG mill. Additional operating changes in the grinding circuit were recommended.A series of trials were conducted in November 2009 where three blasts were fired using a different blast design (hole diameter and explosive type) in the same area of the Apensu pit as the benchmarked material in January 2009. Top and bottom benches (or flitches) from each blast were sent exclusively to the grinding circuit and the material was tracked using PTI’s SmartTag™ system.The results from the six trials showed a significant increase in primary ore throughput at a reduced blend of oxide material. Ahafo have since standardised on these modified blasting conditions for all Apensu ore zones and have been able to sustain higher throughput compared to historical performance on similar material.This paper summarises the phases of the PIO project, the changes made in operating practices and the outcomes of the blasting trials that validated the predicted increase in mill throughput."

Jan 1, 2012

By T. Gerritsen, T. Plikas, K. Ochoa, M. Loveless, R. MacRosty, J. Reichart, R. Pula

Sidewall accretion in a smelting furnace plays an important role in furnace integrity as it provides protection to the sidewall cooling elements and thereby extends the furnace campaign life. The extreme thermal and mechanical stresses in the furnace and changes in the slag chemistry can cause the sidewall accretion to melt or break away decreasing the lining protecting the cooling elements. Thin accretion is highly undesirable as it increases the risk of exposing the cooling elements to the molten bath and in the worst case may lead to a failure. Therefore, monitoring the sidewall accretion on an operating furnace is extremely important to manage furnace integrity and to support safe furnace operation. Operators often generate estimates for sidewall accretion and refractory thickness using either copper cooler temperatures or heat load into the cooling water circuits. Multivariate statistical models, on the other hand, have the capability to consider all the process measurements simultaneously to provide a more reliable estimate. This paper describes the application of multivariate statistical models for sidewall integrity monitoring on a Flash Converting Furnace (FCF) and also discusses the online implementation of these models as the Sidewall Accretion Monitoring System. INTRODUCTION Rio Tinto’s Kennecott Utah Copper (KUC) smelter located near Salt Lake city, Utah operates a Flash Smelting Furnace (FSF) and a Flash Converting Furnace (FCF) to produce high-grade matte and blister copper respectively. Since the commissioning of smelter in 1995, several improvements were made to these furnaces to increase their efficiency and operational safety. At present, Kennecott smelter is known to be among the lowest-emission and highest energy recovery copper smelters in the world. Since the smelter start-up, Kennecott has invested in several advanced furnace monitoring practices to evaluate the integrity of the furnaces and improve their campaign life. An example is their temperature monitoring system installed for the smelting and converting furnaces, which continuously monitors the furnace sidewall temperatures and notifies the operators during temperature excursions. During an investigation on the converting furnace, it was revealed that there were frequent temperature excursions in the settler sidewall area towards the reaction shaft end of the furnace that caused significant furnace downtime. The reason for the sidewall temperature excursions was not clearly known.

Jan 1, 2019

By R. St. C., G. E. Morris, M. Zbik, Smart

Effective flocculation and dewatering of slurry streams containing clays (particularly kaolin and smectites which are often <200nm in lateral dimension) is becoming increasingly urgent. Release of water (often >75 wt%), for recycle and reduced make-up water consumption, from slurries in tailings streams and dam beds is usually slow and incomplete. Changes in settling rates and solids density of tailings containing clays can be achieved in practice by changes in pH, dissolved cations and flocculant additions. To achieve fast separation of clays from water and minimization of retained water, individual particles need to be bound in the initial stages of thickening into large, high-density aggregates, which may sediment more rapidly with lower intra-aggregate water content. Quantitative STIMAN (STructural IMage ANalysis) cryo-SEM imaging, shows that the structure of aggregates formed before flocculant addition has a determinative effect on these outcomes. Without flocculant addition, 4 stages occur in the mechanism of primary dewatering of kaolinite: initially separate particles and aggregates are dispersed (<0.3GP, where GP is the gel point); a partially-gelled chain network then forms linking particles edge-edge (EE) still well below the OP but remains largely suspended; after an induction time, this network structure rearranges from EE to face-face (FF) contacts densifying, compacting and dewatering the aggregates with settling rates well above Stoke&apos;s Law estimates for >20µm particles or aggregates; the GP is rapidly reached during settling producing a network spanning the vessel with compressive strength. This sponge-like structure with EE oriented particles limits slurry dewatering because the steric effect in the resulting partially-gelled structure is much more dominant than the electrostatic effects predicted by DLVO theory. Van der Waal&apos;s forces at very close distances, as particles slide across each other, may be responsible for the EE to FF change in structure. In this way, the previously extended network contracts, and when the solid volume fraction is low, the continuous network breaks apart forming aggregates and aggregate associations as flocs which arc able to freely settle. These densified aggregates settle at increased rate, give lower bed density and retain less water after drainage. With flocculant addition, the internal structure and networking of the pre-aggregates is largely preserved but they are rapidly and effectively bound together by the bridging action of the flocculant(s). The STIMAN analysis shows that there is a inverse correlation of intra-aggregate porosity (and void permeability) with Darcian permeability (and extent of dewatering) whereas there is a strong positive correlation of Darcian inter-aggregate permeability with settling and primary dewatering rate.

Jan 1, 2004

By D. J. MacDonald

UNDERGROUND development at the Lynn Lake property of Sherritt Gordon Mines, Limited, was begun in 1948 with the sinking of the A shaft in the area of the A orebody. By June, 1949, the shaft was completed to a depth of 1,024 feet. Twelve stations were cut, with the bottom level at 992 feet below the collar. Since completion of the shaft, lateral work has been carried out on the 12th level in order to expose the known orebodies and to provide openings from which deeper exploration could be conducted. Dur¬ing the change-over from sinking to lateral work, preliminary diamond drilling was done from the 12th level station to locate the A? ore-body. Later, drilling was carried out from the 5th and 9th level sta-tions, where, also, the outline of the A orebody was established. As the work progressed on the 12th level, and with the commence-ment of drilling below that level, the geological picture was found to be complicated by numerous faults. Instead of operating two drills it became necessary to use at least four. The original plans had provided air sufficient to drive two headings and to operate two diamond drills. The addition of two more air-driven drills resulted in a serious shortage of power.

Jan 1, 1951

By P. Chollet, A Constant

THE RESULTS of a previous investigation ( 1) on the work-softening of some heat-treated steels have led to the conclusion that the occurrence and intensity of the phenomenon is possibly governed by the work-hardening capacity of the material, and the relative amount of retained austenite. The first assumption is compatible with Polakowski's theory (2) that the absence of work-softening, in steels quenched and tempered at relatively low temperatures, may be attributed to the high rate of work-hardening which compensates for, and even out-weighs, the loss of internal energy associated with the simultaneous rearrangement of the original system of internal stresses. Indeed, Polakowski first considered the work-softening as a manifestation of a partial release (by cold-working) of the latent strain energy stored in

Jan 1, 1962

By S. Shimaya, T. Maejima, M. Shimo

"The authors conducted the in-situ gas-tightness tests in a fractured rock at the Namikata underground LPG storage site in Ehime prefecture, Japan. The test consisted of two independent setups, a gas-tightness test that used boreholes, and a chamber-scale test that used a horizontal drift sealed with a concrete plug. In each test, the gas pressure was increased up to the onset of the measurable gas flow to obtain the maximum containment pressure. This paper discusses the hydraulic conditions for gas leakage initiation and the importance of the pore pressure measurement for monitoring the gas-tightness of the LPG storage cavern based on the test results.INTRODUCTIONJapanese first underground LPG storage plant was constructed by JOGMEC, the Japan Oil, Gas and Metals National Corporation, at Namikata in Ehime prefecture in granitic rocks (Kato et al., 2007). The “hydraulic sealing principle” (Åberg, 1977) that utilizes groundwater flow into an unlined cavern to prevent the leakage of gas through fractures in the surrounding rock mass was employed for storage of LPG. This paper describes the results of the in-situ tests performed at the Namikata Site to obtain information on fundamental gas-tightness characteristics of fractured rock. Two types of in-situ tests, a borehole gas-tightness test and a chamber gas-tightness test, were carried out near the storage caverns. Figure 1 shows the cavern layout of the Namikata underground storage plant and the test locations. The storage facilities consist of three caverns (W26m×H30m×L485m). The cavern crown lies at a depth of 150m below the sea level in Cretaceous granitic rock (Figure 1). Water curtain boreholes excavated from the water gallery tunnel at EL-125m level are located above and side of the caverns to prevent water drainage from fractures during the construction stage as well as during operation. The borehole tests were performed from a drilling adit excavated from the eastern end water gallery tunnel, while the chamber test was conducted at the southern edge of an exploratory drift extending from the central water gallery tunnel."

Jan 1, 2015

By L. Li

ABSTRACT Stope backfilling is a common operation in many underground mines, which requires a barricade at the base of the stope near the drift entrance to retain the backfill in place. In this paper, the distribution of pore-water pressure in barricades made of waste rock is analyzed. An analytical solution is introduced and applied to estimate the pore-water pressure along the base and full height of the barricade. Results show that the analytical solution generally accurately predicts the distribution of pore-water pressure obtained from the numerical calculations, especially in the upstream part of the barricade, where it is most critical.

Jan 1, 2013

By P. J. Lunder, R. C. Pakalnis

This paper presents the results of research that has been undertaken in order to develop an improved method of determining the strength of hard-rock mine pillars. Pillars are found in various shapes and sizes in all underground mining operations. Prudent engineering design requires that if pillars are to perform as desired, both the pillar strength and the pillar stress must be determined. A detailed pillar stability study has been combined with an extensive database of published pillar case histories (178)resulting in a new “hybrid” pillar strength formula, “The Confinement Formula”, that utilizes classic strength of rock methods combined with empirical methods. “The Confinement Formula” utilizes a “mine pillar friction term” calculated from the average minor/major stress ratio with-in the pillar core. Statistically, the new formula provides better results at predicting pillar strength for the combined database than the best empirically ft pillar methods that currently exist. “The Confinement Formula” allows for the determination of the strength of mine pillars with an increased level of confidence over previously applied methods.

Jan 1, 1997

By K. M. Sarkar

"In many plant trial s(1,2) it has been proven that very small amounts (10 to 20 ppm) of uranium dissolved in mine water can be effectively recovered by the use of ion exchange resins and this uranium recovery has many advantages. In this paper an economic analysis at different levels of uranium contamination and at different market prices of uranium are described.For this study an operating mine-mill complex with a sulphuric acid leach circuit, followed by solvent extraction (SX) process, is considered, where contaminated mine water is available in excess of process requirements. lt is further assumed that the sulphuric acid eluant containing uranium would be mixed with the mill pregnant liquor stream that proceeds to the SX plant for final uranium recovery.Recovery by Ion ExchangeMine water, in this study, is defined as the water coming from the underground mine, or mine pits, and the run-off water from stockpiles, mine shops, crushing plant , washdown areas, etc.In nature, uranium mainly occurs in two stages; reduced (tetravalent) and oxidized (hexavalent) . The oxidation of sulphides present in the orebody often causes the presence of S04- and acidity in mine water, and this acidic water readily dissolves U+6 part of the depo sit. The react ion between hexavalent uranium, which is dissolved in water as U02+ 2 cation and S04 producing uranyl sulph ate as,"

Jan 1, 1984

By C. M. Campbell

In his report on the Coal Resources of Southern Vancouver Island, Mr. J. D. MacKenzie stated that: "For various reasons it has been imagined that the coal deposits of Vancouver Island are extremely large and readily available." "Unfortunately," he added, "neither of these assumptions is correct." The chief disability under which the Island mines now labor does not concern the extent of the deposits. There is ample coal for the present demand. It does, however, concern the availability of the coal. If it were readily available the fuel-oil competition would not be serious and there would be no competition with Alberta, American, Welsh, or Australian coal along the Pacific Coast, for Vancouver Island coal could be produced at a price that would cut out all competition. The outstanding operating difficulty common to all Island mines is the extreme irregularity of the coal seams. To most people a coal seam is synonymous with uniformity, and in most coal seams a condition found at one point will be repeated at other points in the same seam throughout the basin. The accompanying drawings show how very far this is from being true in the Cassidy mine, which, in many respects, is typical of Vancouver Island mines. Figure I is a plan covering about 160 acres of the Douglas seam, the only workable seam in this part of the district. The area shown represents what has been the best producing part of the mine and indicates the very large percentage of the seam where the coal is either entirely lacking or so small in amount that it cannot be profitably recovered.

Jan 1, 1924

By K. Purazrang, P. Sh. Naseri, P. Abachi

In present work, the comparative measurement of aluminum alloys&apos; resistance to the unstable fracture was provided. Besides, the rupture mechanisms of high strength 7075 and 7050 aluminum alloys were investigated. The specimens were used as solution treated, quenched and aged condition. The elastic-plastic behavior of specimens was determined by carrying out tensile test on cylindrical specimens. The small sized specimen with 6.35 mm thickness and V-notched radius less than 60 µm was used for evaluation of damage properties, in accordance with ASTM B871-96 standard test method. All tear specimens were machined in L-T orientation. The mechanical tests were conducted at RT on an universal Instron machine under cross head speed of 0.1 mm/min. The results of mechanical tests made the evaluation of tear strength to 0.2 % tensile yield strength ratio, as a measure of notch toughness, available. The comparison of specimens&apos; resistance to crack propagation and unstable fracture due to the presence of crack-like strain concentrator was provided using tear test data. The microstructure of specimens was studied under optical microscopy. The rupture micro-mechanisms were analyzed by examination of specimens fracture surfaces using SEM. The microstructure examination indicated almost equiaxed grains on the transverse directions and elongated grains on rolling direction. Moreover, intermetallic particles were evident at microstructure. Considering the SEM fractographs, it seems that the intermetallic particles act as void nucleation and damage initiation sites. However, the damage mechanism of tensile specimens and severely notched specimens, especially near the notched root differs due to stress and strain states.

Jan 1, 2006

By R. A. Crouse

The Tanco pegmatite at Bernie Lake, in the Lac du Bonnet mining district of southeastern Manitoba, is a unique deposit of Li, Rb, Cs and Ta, with substantial reserves of Be and several industrial minerals. This paper summarizes the present state of understanding the regional geology, structural setting, zoning, mineralogy and geochemistry of the pegmatite, and the mining and ore-processing methods used in its exploitation.

Jan 1, 1979

By J. Kronsteiner, E. Kabliman

"In the present work, we developed a Smart Process Control Toolkit (SProC) as a single simulation environment for the modelling of materials microstructure and its interaction with the local microchemistry during manufacturing of semi-finished products. This toolkit supports the data communication between sub-sequent processing steps such as casting, homogenization, pre-heating to deformation, etc. The thermo-kinetical simulation software MatCalc of MatCalc Engineering© GmbH was used for modelling of precipitation kinetics, such as formation of primary and secondary phases and their evolution. An import/export functionality of the precipitation distribution after each processing step was implemented to follow the parameter history. For the evolution of the local microstructure, a Mean Dislocation Density based Model (MD2M) was used. This model consists of two parts: (1) Flow Stress Model for calculation of the total strength during the deformation and (2) Static Recrystallization Model for account of the recrystallization and grain growth after the deformation. Validation was done by a comparison of experimental and simulated hot compression tests of a conventional AA2024 alloy.INTRODUCTION Optimization of a semi-finished products quality, elimination of typical production issues and cost savings are of a great demand for supply industries. However, it is currently not feasible to investigate the whole manufacturing process in detail at an industrial level. Concerning the processing parameters, one must understand the correlation mechanisms between macroscopic properties and microscopic material behavior. Numerical simulations, which could reproduce the real processing conditions on the one hand, and employ a physically based modelling on the other, are thus attracting a lot of attention and their power is no longer under the question. It is well known that e.g. the total strength of the material depends directly on distribution of precipitation particles and mean grain size. In order to follow their evolution during the manufacturing process beginning from casting to the final semi-finished product, and thus be able to control the process, one should use the techniques which would at the same time reproduce experimental processing conditions of real size objects (e.g. sheet, extrusions, etc.) and account for the evolution of a local microstructure and its interaction with the microchemistry. A commonly used approach is to implement a model which would describe the evolution of microstructure based on a dislocation density approach into a user defined material subroutine of some finite element solver. There is, however, also an influence of the manufacturing process by e.g. the evolution of a local microchemistry (formation, transformation and dissolution of the precipitation particles) on the microstructure and thus the macroscopic material behavior. Thus, a method is needed to follow the variable history through the simulation of the whole production chain."

Jan 1, 2018

By Jan Butra

Longstanding mining of copper deposits in the Legnica-Glogow Mining Basin, Poland has accumulated broad experience concerning the impact of geological and mining conditions on seismic and rockburst hazard. Methods of rockburst prevention for deep copper mines have been developed based on gathered data. Methods of rockburst hazard evaluation and rockburst control constitute a set of rockburst prevention measures. Due to their nature and location within the production process, prevention methods can be passive or active. Active methods of rockburst prevention consist of the liquidation of stresses in the areas where they are concentrated through controlled generation of rock-mass tremors and rockburst by blasting works (group extraction blasting, release blasting in the rock mass and pillars able to accumulate the stress, as well as in the roof and floor). Group blasting works as a basic method are very effective in copper mine conditions. Provocation of dynamic events makes it possible to control the timing of their occurrence. In Polish copper mines, all blasting works are made during the absence of miners in the mining fields. Daily distribution of both the number of recorded strong seismic events and volume of energy released, confirm the advisability of using this kind of rockburst hazard prevention. The rockburst hazard prevention methods developed over 40 years of copper deposit extraction are economically reasonable and offer sufficient effectiveness under high rockburst hazard conditions.

Aug 1, 2013

By I. B. Lambert

The guide has been developed by officials from resources and environment agencies in the Australian Government and the South Australian and Northern Territory Governments. It elaborates on the Australian Government?s policy that new uranium mines are to be approved subject to world best practice environmental and safety standards. The guide outlines the best practice principles and approaches that apply generally to mining in Australia, before giving more detailed consideration to best practice environmental protection and regulation for ISR mining.

Aug 1, 2010