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By Didier Fohlen

Three Policy Shifts to enhance IFC?s Accountability ? Comprehensive and dynamic treatment of social, health, safety and environmental risks ?Covers a range of risks encountered by clients in emerging markets ?Framework to anticipate risks and to address them as they arise ?Includes community development, biodiversity, human rights ... ? Effective principles to guide an outcomes-based approach ?By clients and IFC ?Focus on broad community support and value-added sustainable development initiatives Enhanced governance, transparency and disclosure

May 1, 2006

By W. M. Lupton

"Internal grinding mill entries are routinely done by mill personnel during scheduled maintenance periods. Reasons for entry include mill liner life profiles, liner inspcections and replacement and grinding media investigations. These entries require employees to adhere to safety regulations and policies including special permitting, testing, procedure-following practices and the wearing of proper personal protective equipment.A realized semi-autogenous mill entry safety hazard is the unpredicted breakage and occasional shattering of large diameter grinding media while personnel are inside. This was a concern to both media user and supflier. American Barrick's Holt McDermott Mine has improved mi l operational procedures and the media manufacturer has assisted by their developments to essentially eliminate this problem.This paper presents the improvements instituted; and the author's wish to communicate this potential hazard to other large diameter SAG ball users or potential users.INTRODUCTIONAmerican Barrick' s Holt McDermott mine is situated on Highway 101, some 70 kilometers northeast of Kirkland Lake, Ontario, 120 km east of Timmins and 90 km northwest of Rouyn Noranda, Quebec. The mine draws 160 employees from these surrounding areas to extract and process the underground ore, and recover near 60,000 ounces of gold per year. The mill department is completing it's fifth year of operation this spring.The company and the employees are proud of the safety improvements realized over the short history of the mine. Post accident/incident reviews and pro-active safety awareness programs have substantially reduced the mine's accident frequency and severity to date.One of the mill department's objectives is to provide a safe working environment for mill personnel, which includes the interior of the grinding mills."

Jan 1, 1993

By Robert B. Parsons

"The February 18, 1987, Federal Budget contains a proposed amendment which would simplify somewhat the ""successor corporation"" rules in the Income Tax Act. Despite this amendment, though, the important successor rules will continue to be relatively complex.IntroductionThe February 18, 1987, Federal Budget papers propose an income tax amendment whereby the so-called ""successor corporation"" rules would be revised by removing the present provision which limits the application of these rules to a maximum of two ""successions"". The successor corporation rules represent one of the most complicated sets of rules in the Income Tax Act. This month, Tax Notes seeks to explain these rules and the proposed amendment in simplified terms.Basically, the successor rules provide a mechanism for transferring unused exploration and development expenses from one taxpayer to another , in specified circumstances. The aforementioned limitation of two successions refers to the rule which allows a maximum of two such transfers with respect to any particular pool of deductions."

Jan 1, 1987

By Robert B. Parsons

"There is a widespread concern that certain of Finance Minister Michael Wilson's Tax Reform proposals will likely lead to a significant decline in flow through funding after 1988. This does not bode well for the junior exploration sector, which relies heavily on flow-through to finance exploration programs. The exploration industry is actively pursuing various solutions to the problems posed by Tax Reform, in order to ensure that flow-through has a future.IntroductionWhile the proposals contained in Finance Minister Michael Wilson's Tax Reform White Paper may not be as far-reaching as some people had expected, nevertheless the combination of the existing tax rules and proposed new rules offers sufficient complexity to keep pencils sharpened for many months. After having had an opportunity to study Tax Reform since June 18, 1987, the sharpened pencils are suggesting that the White Paper is not without its shortcomings and pitfalls. Insofar as the mineral exploration industry is affected, there is widespread concern that adoption of certain Tax Reform proposals could spell near disaster for mineral exploration in Canada. More specifically, there seems to be a consensus among the industry, as well as some federal and provincial government officials, that the announced phase-out of the ""mining exploration depletion allowance"" (MEDA) would reduce the appeal of flow-through shares to the point where only a fraction of exploration funding would be financed in the future by flow-through."

Jan 1, 1987

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

By Patricia Dillon

EHS Management Standards Communication and Reporting (8) ! Establish processes for internal and external communications ! Designate responsibilities for communication with COI ! Report as defined by senior management ! Report annually to employees, shareholders, COI on EHS and social performance Community Rights and Public Consultation (9) !Identify COI?s and establish process to hear concerns !Acknowledge and respond to complaints !Support local communities !Plan for closure and conduct public consultation !New projects include identification of COI?s, concerns to be considered in design

May 1, 2004

By Nelson Lawrence

An Electrical Risk Management/Inspection Program has been designed specifically for the mining sector in order to provide electrical code expertise and systemic gaps in electrical systems. Goals include improved safety and productivity, reduced injuries and help to enable businesses to better comply with the electrical codes and regulations that govern them. The Electrical Risk Management/Inspection Program is now recognized by some of the world?s largest mining organizations. Since June, 2001 these electrical safety advisory services have been available to underground and surface mine sites throughout Ontario and are now offered throughout Canada and around the globe. This program is also currently being applied to review new electrical installations for mine construction projects thus improving the safety and reliability of mine site electrical systems.

May 1, 2006

By Brendan Parker, Tyron Rees, Steven Hart, Abba Manesh, Ian Mcgaffin

"In September 2009, Newmont began the commissioning of a 3 stage crushing and milling circuit at its Boddington Gold Operation in Western Australia. The Boddington ore has been recognized as one of the hardest and most abrasive ores treated to date and this played a pivotal role in the selection of crushing and HPGR technology for this operation as opposed to the more conventional SABC circuit.This paper will examine the scale up from laboratory to pilot plant and full scale operation of the crushing circuit. There have been many challenges to overcome in the first 18 months of operation; however, the HPGRs have in general met design expectations and performance is expected to improve further with ongoing design changes"

Jan 1, 2012

By I. M. Gordon

"INTRODUCTIONThe Hollinger tailing disposal plant is situated about 1 1/4 miles south of the mill. The area available for tailing covers 620 acres and is roughly 1 ¼ miles long by ¾ mile wide.Tailing was first deposited on the northeast section of the present site. This section, 1 mile long by ~ mile wide, sloped from northeast to southwest, the slope amounting to 106 feet between the northeast corner and the low land to the south west. The low land was wet and a considerable area was covered with muskeg up to 17 feet deep. It was drained by a creek running across the property in a southwesterly direction. Later, when more ground was needed, the low lying mining claims adjacent to the south and west boundaries were acquired to allow for expansion of the plant. This entailed some extra difficulties and expense that would not have been necessary had the whole of the present site been acquired with the original purchase.At the conclusion of milling, May 7, 1968, the site contains nearly 56 million tons of tailing. The top of the deposit is from 70 to 90 feet above the original low lying ground along the northwest, west and south boundaries."

Jan 1, 1969

By S. Kaushik

The control room in a mineral processing plant has become increasingly complicated with complex unit operations coupled with rapidly evolving systems of sensors and control. Even with significant automation, human intervention is required to counter various scenarios that play out every day. A typical control room operator must monitor over 300 individual points of data in order to ensure the safe and efficient operation of the plant. At the same time, the experience of the workforce is decreasing as operators retire and the new generation enters the concentrators. Global competition for skilled operators continues to be strong and the opportunity to apprentice has diminished. The challenge is to provide a skill foundation for the operators so that they can be effective in the concentrator in a timely and safe manner. Progressively, the industry is turning to dynamic simulation tied into the control system. The simulator environment operates behind the control system to emulate the plant operation, reacting as the plant would when a change is made. The operator drives the process, with realistic feedback, which enables learning in a safe environment. This paper will take the reader through a green-field case study and discuss the effectiveness of integrating an operator training simulator (OTS) on the operator’s learning curve.

Jan 1, 2014

By T. H. Patching, M. W. Mikhail

"The gas sorption and emission characteristic of coals are important to the planning and conduct of mining operations. Methane drainage from coal strata can also provide a supply of fuel in certain circumstances. Gas emissions have also created hazards during the handling and transport of coals and the release of gas also appears to be related to the yield of fine sizes during mining and processing operations.This paper summarizes studies at the University of Alberta on the permeability and gas emission of certain bituminous coals. Permeability of 'solid' samples was found to be drastically reduced by confining pressure. An emission index, .P, which has been related to outbursting behaviour of coals, has also been related to the proportion of fine s in cleaning plants. Gas sorption isotherms are dependent on temperature, moisture content, the gas involved and the type of coal and can be approximately expressed by the Langmuir or the Freundlich equations. Sorption values in sections taken across a given seam were similar but considerable differences were found in . P indices in the different coal layers of a seam.IntroductionThe emission of gases, especially of methane, from coal has been a subject of great interest (and sometimes a matter of life and death), to those who dig and handle coal since it was first mined from underground pit s. Many studies and investigations have been carried out on gas occurrences and emissions but our knowledge of the precise mechanisms of gas sorption, desorption and flow from coal is still incomplete. It is the purpose of this paper to review the principal factors involved in these processes and to briefly rep ort some of the results that have been obtained by studies in the laboratories of the Department of Mineral Engineering, University of Alberta, and Coal Research Laboratory, Edmonton, CANMET"

Jan 1, 1986

By G. J. Reid, D. H. Stewart

"A diversity of structures and rock types in the Aft on pit has resulted in the occurrence of several different types of wall failure. Delivery of ore to the mill has not been affected and safety has not been compromised thanks to effective remedial 1V0rk and to a system of structural mapping, back analyses of failures, groundwater monitoring, and simple movement monitoring. Remedial measures have included artificial support, dewatering (including vacuum-assisted drainage), flattening of slopes and temporary buttressing. This paper describes six different wall failures at Afton and highlights the features of each. Examples given include rates of movement, extent and direction of movement, and piezometric responses. The practical, low-cost monitoring system was sufficient in one case to allow the prediction of date of failure. IntroductionThe Afton copper deposit is located 13 km west of Karnloops, British Columbia and has been mined for nine years out o f an expected eleven-year life. Open pit mining has reached 700 feet below sur face and is designed to proceed to 970 feet below surface by the time the pit is completed. The excavation is in a structurally and lithologically complex environment. Inevitably, some wall failures have occurred but these have been limited to small, manageable failures which have not compromised production or safety. To handle the failures it has been necessary to understand their nature. Of prim e concern has been the rate s of movement, but displacement vectors and hydrology have been monitored as well. The monitoring system is based on EDM surveys and on wire extensometers and plates set across cracks. Water levels have been read in standpipe piezometers. At Afton the emphasis has been on simple, practical, and inexpensive monitoring and because rock type s and structures play such a major role in any failure, detailed geologic al mapping is carried out."

Jan 1, 1988

By H. Soto, J. Jara, F. Nava

A method has been developed to recover cyanide and copper from cyanidation effluents contaminated with thiocyanate and copper-cyanide complexes. Copper is precipitated as copper thiocyanate or as copper cyanide depending on pH and the concentrations of thiocyanate and cyanide present in the effluent. The copper precipitate presents good dewatering characteristics and can be easily separated from the effluent by thickening and filtration. The solution containing the bulk of the cyanide is then oxidized with ozone to transform the remaining thiocyanate into cyanide. This results in a regenerated solution rich in free cyanide that can be recycled to the cyanidation process. Careful control of the pH of the solution is required. First pH of the effluent is lowered to optimize the precipitation and oxidation stages, then the pH is restored to an alkaline value to regenerate the cyanide solution. Recoveries of over 96% copper are obtained. Free cyanide in the regenerated solution corresponds to up to 160% of the total cyanide contained in the original impure effluent. (The balance being accounted for by the cyanide obtained by the oxidation of thiocyanate). The efficiency of the thiocyanate oxidation stage is 85% to 90%. The method has been demonstrated at bench scale with effluents of various cyanidation plants of northern Quebec. A preliminary economic evaluation indicates that the procedure would be profitable for effluents rich in copper and thiocyanate. This is the case for most barren bleeds of Merrill Crowe and heap leaching operations and also certain CIP tailings of gold ores containing copper impurities. Environmentally the procedure is a better alternative than the current detoxification methods based on the oxidation of cyanide that do not allow for copper recovery and that have difficulties in producing a final effluent with acceptable levels of contaminants such as ammonia, thiocyanate and copper.

Jan 1, 1996

By Robert D. Brown, Robert B. Parsons

"Careful tax planning and proper attention to the regulations can result in an optimum deduction ""of the 25% federal resource allowance. Introduced in the Income Tax Act in1976, in part to compensate for the disallowance of provincial mining taxes and royalties. the 25% ""resource allowance"" is a permitted deduction in computing taxable income from mining and petroleum. However, the rules relating to the deduction are complex, and the importance of the deduction which can readily exceed 25% of net income- is frequently underestimated. This month, Tax Notes discusses the basic rules of calculating the resource allowance, and suggests some tax planning aspects which may warrant consideration.May 6, 1974 - "" .. . our provinces have adjusted royalties, mining taxes and other arrangements to derive what they perceive to be a fair share for the benefit of their people. However, a provincial resource is also a national resource... I am proposing that revenues derived by provincial governments in respect of production from a… mineral resource should no longer be.\ deductible in computing the income of the operator. .. I am proposing that. .. there be an extra abatement from federal income tax in respect of taxable production income.. .fifteen points in the case of mineral profits. .. "" - The Honourable John N. Turner, Minister of Finance. June 23, 1975-"" '"" to meet, at least in part, the request for some form of deductibility in the tax system for provincial resource levies... to offer more incentive to those who explore and develop in Canada. .. I am now proposing, the extra fifteen point abatement of federal taxes would be withdrawn... at the same time, I am introducing a new resource allowance, which would be an extra deduction from income equal to 250/0 of production income.. ."" - The Honourable John N. Turner, Minister of Finance."

Jan 1, 1980

By E. Ozberk, N. Gibson, W. G. Davenport

"In the 1950s, Canada produced more than ninety-five percent of the non-communist world's nickel and achieved dominance in terms of production, technology and pricing policies.Over the past thirty years there have been dramatic changes in the nickel industry to the extent that Canadian production is now less than thirty per cent of the total.In this document we have presented statistics relevant to this transformation and reviewed the technology, particularly with regards to energy and environmental considerations.Under the new market conditions nickel producers are likely to face more difficult competition than they have encountered in the past.The economic scene and measured nickel reserves dictate that for the purpose of increasing production, new nickel smelters will not be built in Canada in the foreseeable future. However, in order to reduce sulphur dioxide emissions, Canadian nickel smelters will possibly go through some modifications or rebuilding.IntroductionThis paper presents a review of the Canadian nickel industry in relation to the world nickel industry. Major changes are described which have occurred in the characteristics of the nickel market over the last thirty years. The pre sent status of the nickel market with respect to Forecasting future trends is reviewed and attempts are made to predict what further changes will take place in the next two decades. Comparisons are made of the economics of producing nickel from sulphide ores and oxide ores and the advantages and disadvantages the Canadian nickel producers face.A brief critique of the existing and emerging nickel production technologies in Canada and the world is carried out and attempts are mad e to predict the changes which may take place in the foreseeable future."

Jan 1, 1983

By K. E. Waters, J. E. Nesset, F. Rosenblum, J. A. Finch, S. Moon

"Some materials when exposed to various conditions can exhibit a rise in temperature without requiring an external heat source. Generally referred to as pyrophoric or self-heating substances, they challenge the safety of materials handling, storage and transportation. Reliably assessing the self-heating potential of materials is thus essential. Over the years a number of test protocols have been developed. A widely accepted method is that recommended by the United Nations to certify the safety of shipping pyrophoric goods. Our test work on sulphide materials has shown that the U.N. test can give false negatives if the sample oxidation history is not considered. Depending on the degree of oxidation (“weathering”), the same sulphide material can exhibit self-heating ranging from safe to hazardous. For concentrates, oxidation can occur during storage and transport making the sample weathering history an important consideration in the test work. To make the U.N. test, and other single-stage self-heating procedures, more reliable in assessing self-heating potential when testing sulphide materials, it is suggested that a weathering step be incorporated in the test protocol. This test work for two sulphide samples, an ore and a concentrate, demonstrates the impact of incorporating a weathering stage in the test protocol. INTRODUCTIONSelf-heating occurs when exothermic reactions produce heat faster than can be dissipated to the surroundings. Numerous substances self-heat, ranging from wood chips and powdered milk to coal and sulphide minerals (Beever & Crowhurst, 1989; Hudak, 2002). Mixtures of sulphide minerals, most notably those containing the iron sulphide pyrrhotite (Fe(1-x)S), commonly encountered in the extraction of base metals (e.g., copper, zinc, lead, and nickel), are particularly prone to self-heating (Rosenblum, Nesset, & Spira, 2001; Payant, Rosenblum, Nesset, & Finch, 2012). In the mining and subsequent processing stages, the minerals are progressively liberated and finely ground, then separated, usually by flotation, with the resulting concentrates stored and transported to smelters for metal extraction. At most of these stages the sulphides are exposed to both moisture and oxygen, conditions that promote partial sulphide oxidation and the formation of elemental sulphur. Studies have shown that pyrrhotite, in particular, readily oxidizes to form elemental sulphur (Bernier & Li, 2003; Belzile, Chen, Cai, & Li, 2004; Somot & Finch, 2010). The elemental sulphur becomes fuel for further self-heating as the temperature of the mineral mixture increases above 100 oC (Rosenblum & Spira, 1995; Somot & Finch, 2010). It is believed the propensity of pyrrhotite to self-heat is a result of its iron-deficient, and hence somewhat unstable structure. It is worth noting that pure metal sulphides (with the exception of pyrrhotite) do not exhibit appreciable self-heating. A mixture of minerals sufficiently different in their electrochemical rest potential is required to initiate self-heating at ambient temperatures (Payant et al., 2012)."

Jan 1, 2016

By Ben Cottrell

In this paper technical drilling is referred to as the process of collecting engineering and metallurgical parameters for subsequent mine design considerations. Throughout the development of a mineral exploration property there are various opportunities to ?piggy-back? technical drilling onto the routine exploration drilling process, helping to reduce future costs and delays associated with re-drilling and missing information. This article is written from the engineers and metallurgists point of view, to outline some best practices for exploration borehole planning and technical data collection requirements.

Aug 1, 2013

By J. E. Gill

"The Wasa Lake property is a block of about 1,640 acres in Beauchastel township, Quebec. Gold was discovered there first in 1936 in what is now known as the 'Southern area ( Fig. 1). Stripping and trenching were followed by 9,218 feet of diamond drilling in twenty holes. A number of good intersections were obtained, but their interpretation in terms of ore was difficult. A shaft was then sunk to 220 feet vertical depth. Thirteen hundred feet of lateral work and 543 feet of diamond drilling were completed at the 200-foot level before work was discontinued in 1938. Results up to this point had been just fair.Early in 1944, surface diamond drilling was resumed. The first hole cut material of ore grade in a strong shear zone 1,000 feet north of the old workings, and holes to the east and west showed this to be an extensive gold-bearing zone.In August 1945, a main working shaft was started. This has been sunk to 550 feet slope depth. A cross-cut at 390 feet vertical depth was driven to the ore zone and, by drifting and drilling at regular intervals, a length of 725 feet had been tested to December 31st, 1946 ( Figs. 1 and 2). The results check those from surface drilling quite closely.In the main zone, scoping widths from 8 to 40 feet and averaging about 25 feet are indicated. The grade after dilution should be about 0.15 oz. gold a ton and operation will probably start at 1,000 tons a day."

Jan 1, 1954

By Frank Wright

"The Icon Sullivan Joint Venture ore deposit was discovered in June, 1965 by Messrs. Paul Benard, Bob Galipeau and Mac Watson working under the direction of Mr. Andrew J. Troop, as employees of the Icon syndicate. The deposit is located on the Waconichici River as the south end of Baie du Poste of Lake Mistassini, approximately 45 miles north of Chibougamau. Property acquisition and Winkie drilling was followed by a diamond drilling program to evaluate the deposit. Stripping of the open pit area connnenced in the late fall of 1966 and the first test sample of ore was shipped to Chibougamau in December of that year.Regular ore shipments to the mill of Merrill Island Mining Corporation Limited for concentration commenced May 25, 1967. Production to December 31, 1970 amounts to 42,960,000 pounds of pay copper.The ore is chalcopyrite in white quartz dolomite, and it contains a very small amount of precious metals. The quartz dolomite assumes a flat to gently dipping attitude and is associated with a graphitic argillite contact zone on both hanging and footwall sides, in dolomitic limestone rocks. There is practically no other sulphide present in the ore.During the summer of 1969 a series of pre-concentration tests were completed and a Wemco heavy media sink float plant was installed in late 1969 and early 1970. This pre-concentrator eliminates at least one third of the ore mined in the form of barren quartz dolomite prior to ore shipment by truck to the concentrator in Chibougamau."

Jan 1, 1971

By V. Ramachandran

The successful advent of solvent extraction (SX) reagents for copper recovery and improvements in electrowinning of copper to produce LME grade A copper cathode have paved the way for the hydrometallurgical treatment of copper oxide and low grade sulfide ores. This has resulted in about 25-30% of the world's copper being produced today by the Leach-SX-EW process. The obvious next step was to develop processes for the hydrometallurgical treatment of copper sulfide concentrates, as an alternative to a typical smelter-refinery complex. The current paper updates the processes that have been developed to date with emphasis on processes that are being commercialized or that are seriously under consideration for commercialization. Most of the discussions relate to the hydrometallurgy of chalcopyrite concentrates, which account for about 70% of the world's known copper reserves. In summary, in the last thirty years, the hydrometallurgical treatment of copper sulfide concentrates has attained full maturity and will be a serious option to contend with while evaluating any future new copper plant.

Jan 1, 2007