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By José Carlos Marques

This paper addresses recent calls to study the role of the state in private regulation. Using an historical, organizational-field approach, I trace and explain the evolution of public debates and interaction of different forms of regulatory initiatives dealing with Canada?s mining industry. The empirical evidence presented calls attention to the interaction amongst different regulatory forms, as well as the conditions under which the state will encourage fragmented initiatives, rather than facilitate and catalyze regulatory strengthening and consolidation. As such, my analysis: problematizes the underlying assumptions used as a starting point by the growing literature on the role of the state in private regulation; connects and juxtaposes recent scholarship to more established literature on regulatory state failure and self-regulation. I also contribute to the discussion on Canada?s CSR policy, outlining the likely regulatory effects of the current policy framework.

Aug 1, 2013

By Charles Graham

For hundreds of years the standard vertical mine shaft was rectangular shaped and timber lined. There are many advantages to rectangular shafts but as mines became deeper the circular shaft became more popular. The chief advantages of circular, concrete lined shafts are their ability to resist lateral pressure and they offer less resistance to ventilation air. A number of elliptical shafts have been sunk in an attempt to realize the advantages of both the rectangular and the circular shaft. A concrete lined elliptical shaft provides better space utilization than a circular shaft, would allow for shaft sinking with two double drum hoists, as well as concurrent level development. The design also makes one sided stations possible and provides for a simple headframe design.

Feb 1, 2008

By S. C. Bouffard

Barrick's Zaldivar operation in Chile produces copper by heap leaching, solvent extraction, and electrowinning. The heap consists of a dynamic pad, and its stacking and operating conditions have changed over its 11 years of operation. These changes have included pad re-mining midway through the cycle, tightening of the irrigation drip lines, an increase of the coarseness of the particles, and an increase of the heap height. This paper reviews the heap operating data to understand the effects of these changes on the kinetics and recovery of copper minerals. Field tests demonstrated that neither re-mining nor tightening the irrigation grid added value for both low and high grade oxide and sulfide ores. The P80 of the feed ore was increased by 0.8 mm, which did not reduce the copper recovery of oxide and sulfide ores. The increase of the heap height above 8 m lowered moderately the copper recovery from sulfide minerals, and very slightly the recovery from oxide minerals. Despite the lower recovery, the higher tonnage stacked in the taller heap increased the copper output. Optimizing the chemistry of the agglomeration and feed solution holds more promise for increasing the copper recovery than the above physical changes.

Jan 1, 2007

By Jr. Santos, T. V. Pignaton, R. B. Gomides, W. Phillips, M. P. D. Gomes

Kinross Paracatu started the operation of the new gold processing plant in the end of 2008, being composed by one SAG mill and two ball mills. During the first year of operation the plant had several problems related to stability and throughput capacity, mainly due to low grinding efficiency of the ball mills. In this period many actions were taken to maximize the throughput rate. Among the actions are reducing the size of balls in the mills, increasing the ball charge in the SAG mill, changing cyclone configuration and return of circulating load to SAG mill. With better stability of the circuit, the second stage of improvements has begun with the objective of increasing throughput rate and also reducing operation costs. Among the actions are the optimization of ball charge in the mills and a better operational control of cyclone parts. After two years of operation was obtained a significant increase in plant capacity, but still requires the addition of a third ball mill in order to maximize the use of SAG mill, which has spare capacity.

Jan 1, 2012

By J. W. Keyes

"The original grinding circuit at East Malartic consisted of two 8 by 8 C.A.C. mills in closed circuit with two 72 inch Akins Classifiers and an 8 by 10 secondary mill in closed circuit with two 48 inch duplex classifiers. With this circuit, we experienced a drastic drop in tonnage from one month to another, due to variations in the hardness of the ore. The first step to overcome this difficulty was made by increasing the critical speeds of the mills from 78% to 82%. This resulted in an increase in the secondary mill throughput; but, when the change was made on the primary mills no increase was obtained.The drastic drops in tonnage were still experienced and through working with Allis Chalmers the 8 by 10 mill was converted to a rod mill and the two 8 by 8 n1ills to secondary mills. This change eliminated the two 72 inch Atkins classifiers and the scoops on all the mills, since the 48 inch Akins classifiers sands could then be fed by gravity to the secondary mills through feed pipes.The rod mill and secondary mill discharges were fed to a common pump box using 5 by 5 S.R.L.'s running at 1085 R.P.M. with a twenty-five foot head. When this was done the pumping costs jumped from $105. 00 for 6 months to $1050. 00 in one month, or from 0. 0004 to 2. 75 cents a ton milled. Several factors contributed to this jump in pumping costs as follows:"

Jan 1, 1964

By J. Fournier

A novel sol ? gel (SG) synthesis procedure utilizing varying ratios of glycine and ethylene glycol to total metal cations has been developed to create high purity nanometer sized La0.65Sr3.5MnO3 powders. X-ray powder diffraction (XRD), transmission and scanning electron microscopy (TEM, SEM), and dynamic light scattering (DLS) have confirmed that the crystallite sizes of such powders are ~ 20 nm, and the aggregate particle sizes vary between 100 to 300 nm. Mixing varying weight percents of SG LSM powders with commercially available Praxair LSM in a composite LSM/YSZ functionally graded cathode has been shown, through the use of electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV), to exhibit enhanced oxygen reduction kinetics vs. at conventional cathode materials.

Jan 1, 2005

By C. A. Young

"The stabilization of tailings has been a matter of concern to the Mining Industry for many years. In earlier times, when mines were small and only high grade ore deposits were mined, the problem was not a great one. But, more recently - during the last 30 to 40 years - the increased world demand for various metals, combined with the vast strides that have been made in the improvement of metallurgical extraction processes, have resulted in the development of lower grade ore bodies.About 30 years ago The International Nickel Company started experiments to stabilize the surface of the tailings and prevent them from becoming a dust source under certain weather conditions. The use of chemicals to form seals, covering with crushed stone, mulching with straw and some early seedings were some of the stabilizing methods tried. Results were either unsuccessful or impractical economically.In 1954 a series of experiments to establish vegetation on the tailings began. Varying degrees of success were achieved but however unsuccessful a particular scheme turned out, the attempt to find a solution was never written off. As we look back, we realize that the first significant break-through came as the result of three test plots planted in the spring of 1957. Each plot covered an area of approximately one-third of an acre. One plot was successful and persisted until it was covered up by the expansion of the tailings area in 1961.In 1960 a review of all our test plots to that date was carried out to assess the factors which effect the chance of grass being established."

Jan 1, 1969

By Ferenc Molnár, David H. Watkinson

Abstract - Cu-Ni-PGE footwall ore deposits were studied in the McCreedy East and Whistle mines along the North Range, and the Lindsley and Little Stobie mines along the South Range of the Sudbury Igneous Complex. The footwall ores in these localities differ from typical magmatic Fe-Ni-Cu- PGE deposits in the Sudbury mining camp: they have higher Cu/Ni ratios, higher PGE content, veinlike appearance and ubiquitous association of ore with hydrous silicates. Results of comparative fluid inclusion petrography and microthermometry of footwall ores indicate that high temperatures (300°C to 480°C) and heavy-metal rich saline (up to about 40 NaCl equivalent wt% salinity) fluids were associated with the formation of the PGE-rich footwall ores at moderately high pressures (around 2 kbars). However, several, possibly independent fluid circulation stages were also found at the different localities and there also are differences in detailed characteristics for ore-forming fluids especially comparing data from the North Range and the South Range. Thus, in addition to the high temperature and salinity of fluids, there are local variations in the nature of hydrothermal processes. These differences may be related to the diverse origin of fluids (magmatic, metamorphic, and formational brines) and their differing extents of interaction with the compositionally different footwall lithologies.

Jan 1, 2001

By M. Takebayashi, K. Takenaka, S. Matsubara, T. Yoneyama

The cathode production of Toyo Smelter and Refinery, owned by Sumitomo Metal Mining Co., Ltd. reached 450,000 tons per year in 2016 with three tank houses. Niihama tank house commenced operations in 1919 with conventional sheet cathode technology. Approximately 100 years of operation experience and the technical development enabled that the current density of Niihama tank house and the Toyo tank house #1 increased to 320 A/m2. These operation techniques were utilized at the Toyo tank house #2 which started in 2005, and its current density reached up to 350 A/m2 with permanent cathode technology. In order to achieve high current efficiency under condition of 350 A/m2 operation at Toyo tank house #2, continued efforts had been made to verticality of anodes and permanent cathodes. To improve verticality of anodes and cathodes, reduction of short circuit ratio by changing the shape of the anode, optimizing the anode pressing machine and off-line process for rectifying the distortion of permanent cathodes was carried out. In addition, concentration control of electrolyte and expansion of Ni removing ability from the electrolyte prevented passivation. Finally, more than 96% of the current efficiency was stably confirmed. INTRODUCTION Today, Toyo Smelter and Refinery of Sumitomo Metal Mining operates three tank houses in Japan, namely, Toyo tank house #1, Toyo tank house #2, and Niihama tank house with a total capacity of 450,000 metric tons of copper cathodes. Figure 1 shows the trend of cathode copper production and the current density at three tank houses over the last 10 years. Cathode production by Toyo Smelter and Refinery reached 450,000 tons per year in 2016 with three tank houses.

Jan 1, 2019

By Robert W. Baker

"Brunswick Mining and Smelting commenced production at the No. 12orebody, a lead/zinc/copper/silver deposit, situated some seventeen miles southwest of Bathurst, New Brunswick, in 1964 at 4100 tonnes per day. Today it operates at 10500 tonnes per day.Brunswick has utilized underground incentives since commencement of operations. Early incentive systems were “off the wall"" based on those in effect at other properties then manipulated to fit, often hack calculated from actual performances to tm1ve at the desired result. If subsequent payouts were considered too high the rates were simply reduced, often retroactively. A large amount of this was' subjective and depended to a large extent on whoever was handling the bonus, in conjunction with senior mine department staff.In 1971, it was' decided that a more scientific approach was needed, particularly with the introduction of the new cut-and-fill mining. After some research, a system based on Work Study was selected. Another major mining company employing such a system loaned one of their experienced employees to train some Brunswick personnel in the art of Work Study and conversion of data to incentive rates, and in 1972, the first such developed incentive rate was-introduced.Along the way, borrowing from others where necessary, a set of Brunswick principles and parameters were developed. While refined to some extent, these remain basically the same today.Improvements in methods and equipment have resulted in improved performance and reduced costs. The use of underground incentives has played an important role in this. A/though individual bonus earnings have steadily increased, bonus cost per tonne has remained nearly constant - in real dollars, it has regularly decreased. These are two of the main parameters of a successful system."

Jan 1, 1995

By M. B. McClenaghan

"The Ontario Geological Survey completed a regional till sampling project between 1984 and 1988 in the Black River Matheson (BRiM) area of northeastern Ontario. The project was designed to aid mineral exploration in the area by documenting the Quaternary stratigraphy and by providing a database of till geochemistry. This paper summarizes the results from the sonic overburden drilling component of the BRiM project carried out in areas of thick drift (> 5 m). Results from till sampling in areas of thinner drift (<5 m) have been presented in a separate paper. Approximately 1100 till samples were collected from 225 sonic drill holes. For each sample, the non-magnetic heavy mineral (>3.3 S.G.) and fine (-250 mesh) till fractions were analyzed geochemically and visible gold grains were recovered by panning.Gold and other multielement geochemical data were plotted using proportional symbols to highlight anomalous areas and to demonstrate how to evaluate and interpret a very large geochemical dataset. Thresholds for identifying anomalous concentrations of Au in till samples, defined using the 95th percentile, are 1500 ppb and 12 ppb for the heavy mineral and fine fractions, respectively. The heavy mineral fraction of older ti1ls and to a lesser extent, Matheson Till, display a number of significant gold anomalies in the study area, which in a few cases, are associated with base metal anomalies. The vertical position of gold anomalies in Matheson and older ti1ls varies from directly on bedrock to several meters above the bedrock surface and can provide information of relative ice transport distances."

Jan 1, 1994

By Henri-Louis Jacob

Le Québec dispose de ressources en silice abondantes et diversifiées, pouvant convenir dans l'ensemble à la plupart des usages industriels. Dans les terrains Paléozoïques des BassesTerres du Saint-Laurent et des Appalaches, les ressources identifiées comprennent les grès quartzitiques purs du Croupe de Potsdam (Cambrien), exploités notamment à Saint Canut au nord de Montréal comme source de sable de silice pour l'industrie du verre; les arénites quartzitiques des Formations de Val-Brillant (Silurien moyen) et de Kamouraska (Ordovocien inférieur) exploitées dans l'est du Québec comme source de fondant métallurgique; les grès friables de la Formation de Guigues (Ordovicien) au Témiscamingue, à partir desquels on produit des sables de silice utilisés notamment en fonderie et en filtration. Dans la province structurale du Grenville, au nord du fleuve Saint-Laurent, les métaquartzites purs du Supergroupe de Grenville représentent une source importante de silice pour la production de silicium, de ferro-silicium et de carbure de silicium. Des veines et amas de quartz ont aussi été exploités un peu partout au Québec comme source de fondant métallurgique ou de silice ultra-pure pour la production de silicium métal. Quelques dépôts de sables naturels, généralement d'origine marine ou deltaïque sont finalement exploités dans la région de Montréal comme source de sable pour des usages n'exigeant pas un produit de haute pureté.

Jan 1, 2001

UBC Mining Department As an example ?35 Graduating ?14 with Jobs ?6 with Strong leads ?149 Undergraduate ?Projecting 43 second year students ?10-30 % Dual Degree

May 1, 2010

By V. Evans

Mine lateral development advance rates currently average about 5 metres (16.5 ft.) per day. Granduc Tunnel hit 35.1 metres (115 ft.) on their best day, 12 km from the portal, single heading forty-three years ago. This Canadian mining record remains an excellent example of rapid drill and blast excavation with suggestions for improving current practice.

May 1, 2011

By Philip Peck

Mine closure issues ?Narrow issues: ?Environmental focus; ?Broad issues: ?Social issues and sustainability; ?Continued importance of mining; ?Historical legacies from closed mines; ?Barriers to development; ?Migration [ir]reversibility Dealing with closure issues ?A matter of choice ?Option 1: Engagein solving closure problems as best possible; ?Option 2: Exit, leaving the playing field to firms not interested in solving problems ?Option 3: Delay, till better time to enter or until early entry [by others] fails and pick property up cheap [?].

May 1, 2006

By George Hope, Dave Green, Jacques McMullen

The Est Malartic mill has been treating massive sulphide, copper/gold ore from the Bousquet 2 mine since 1989. The need to minimize copper content in flotation tails which are leached for gold recovery and to produce a saleable copper concentrate led to the evaluation of Conventional, Column and HG flotation methods. The HG method was preferred and two full-scale cells were installed and operated over a two-year span. In 1992, it was decided to expand the mill capacity from 1500 tpd to 2500 tpd. A total of nine additional HG Tank Cells were installed to provide additional roughing and cleaning capacity. The expanded plant has been operating since June 1993.

Jan 1, 1994

By J. H. Bernard, K. Žák

The three traditional types of Variscan vein Pb-Zn-(Ag) mineralization recognized in the Bohemian massif from historic paragenetic studies are confinned by modem metallogenic studies. Stable C, S, and O isotope data, as well as Pb and Sr isotopic ratios of the deposits, indicate a predominantly crustal origin of the constituents in all three types. Although the data also suggest differences in temperature and pressure of formation, and the oxidation conditions and nature of the hydrothermal fluids, nonetheless they are consistent with prevailing metallogenic classifications of the vein mineralization

Jan 1, 1992

By Terry Bachynski

_ Regulatory Process _ Approval Timelines _ Trends _ Stakeholder Consultation Expectation _ Challenges _ Initiatives for Regulatory Process Reform _ A Better Way? Alberta Regulatory Process _ Regulatory Approval of a major capital development requires multiple approvals from several regulatory authorities: ? EUB ? Decision Report approves development scheme and recommends conditions for other regulatory agencies ? AEnv ? approvals to construct, operate and reclaim required prior to any in field construction activity ? Federal - approvals for federally regulated activities ? Municipal ? Development Permit

May 1, 2004

By Sergio Fuentes

During the past fifteen years, mines utilizing the block caving method have improved performance and systematically reduced total mining costs. This paper describes improvements in mine design, mine planning and mine management, including methods enabling the Chilean and International mining industry to ensure cost savings and productivity growth while using the block caving method. These improvements have encouraged the re-evaluation of underground operations at operating and closed open pits, and challenge surface mining applications as the only low cost mining method. This paper describes a strategy to estimate the optimum open pit to underground transition time during the life of a mine.

May 1, 2003

Presentation Agenda ?Background ?OEM Recommendations before RCM ?Operating Context ?OEM Recommendations after RCM ?Reality of Failure ?RCM Deliverables ?Maintenance program optimization ?Spare part optimization ?Implementation ?Further Considerations -Three scenarios ?Summary and Conclusion Background ?P&H Mining?s LCM division performed a RCM study on a ?generic 4100 XPB shovel?in Milwaukee. ?P&H soon realized that the analysis required context -The recommendations were manufacturer knowledge based. -The outcome based on manufacturer requirements. -The strategy was not applicable to all machines, etc. Operator experience and ?local knowledge? are key to the success of an RCM analysis. P&H approached Teck Coal?s Fording River Operation to assist with ?Operating Context?. Teck provided operator and maintainer experience.

May 1, 2010