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By D. J. Robertson

"THE copper smelting operation of the Hudson Bay Mining and Smelting Company, Limited, at Flin Flon, Manitoba, generates a gas flow of 350,000 c.f.m. at n.t.p. This gas stream passes to atmosphere through a 20-foot diameter by 250-foot brick stack, carrying with it an appreciable dust burden in the form of metallic oxide fumes. The flow constituents during the period 1952 and 1953 and •before gas filtration was included in the treatment scheme are shown in Table I. This paper describes the gas filtration treatment which was installed in 1957, using glass cloth media to recover this dust burden, and discusses the associated problem as its treatment for recovery of zinc and cadmium.The metallurgical details associated with the problem are illustrated by a description of the material flow sequence of the Company's hydrometallurgical zinc plant and copper smelter. In this ore processing complex, the zinc plant and copper smelter form an integrated unit within which intermediate zincrich products of each operation enter the treatment circuit of the other."

Jan 1, 1960

By L. R. Gremillion

Chemical and mineralogical data on 25 apatitic phosphate ores of diverse origins from commercial deposits around the world were widely variable. From 14 to 18 chemical constituents of each sample were determined, and each sample contained 4 to 10 mineral phases. Altogether there were 34 different mineral phases, many of which occurred in only one sample. The samples contained varieties of francolites, fluorapatites, and mixed hydroxyl-fluorapatites. The apatite compositions calculated from the chemical data showed that certain types of substitutions were characteristic of different apatite varieties, but every variety had some degree of substitution of (CO3)2 for (PO4)3 and the P2O5 contents of the apatites ranged from 35.1% for a North Carolina apatite to 41.9% for a Missouri apatite. In a concentrate with a grade of 32% P2O5, the North Carolina sample should contain about 8.7% gangue and the Missouri sample about 23.7% gangue. To optimize the digestion process of a phosphate are, it is necessary to consider the dissolution behavior of the different mineral phases during acidulation and the effects they may have on the chemical properties of a fertilizer intermediate. In the production of wet-process acids or superphosphates, the acidulation of certain minerals may cause foaming and formation of sludge, filtration, corrosion, and handling problems.

Jan 1, 1978

By Fawcett M

Pine Creek Goldfields Limited (PCG) is rehabilitating the Enterprise Pit to an aquatic habitat and potential water resource. This paper discusses the development and implementation of that plan. Pine Creek Goldfields Ltd's Enterprise Mine is located approximately 230 km south of Darwin. Open cut mining of the orebody commenced in 1985 and continued for eight years with 14 million m3 of ore and overburden extracted. Geochemical testing of exposed rock types in the pit has demonstrated a propensity to produce acid, and dissolved metals. A plan of management has been developed and implemented to minimise the risk of acid formation and improve the overall water quality in the final void. In developing the plan prime consideration was given to reducing the potential for pit water to impact upon the regional groundwater. An interception system was constructed on Pine Creek to divert approximately 9 km2 of upper catchment into the northern end of the Pit. Construction of the diversion system was completed in December 1993 and a comprehensive surface and groundwater monitoring program initiated. The monitoring program and associated studies are also discussed.

Jan 1, 1994

By B. E. Halbert, K. T. Himbeault, S. L. Fernandes, R. L. J. Phillips, B. J. Topp

The Beaverlodge uranium mining and milling facilities operated from 1952 to 1981 with about 94% of the ore extracted from the main underground mine and 6% from smaller satellite deposits. Decommissioning work occurred from 1982 to 1985 involving periods of shutdown, salvage and reclamation. Transition phase monitoring, leading to eventual delicencing commenced in July 1985. Over the last 15 years, discharge from the tailings management facility (TMF) and a fresh water stream, impacted during the operational phase by tailings spills, has improved in water quality for most parameters of concern. Loadings to the environment of three key contaminants (radium-226, total dissolved solids, and uranium) have consistently been less than during the operational phase with radium-226 having the greatest variability. Outstanding environmental issues associated with the recovering drainage system formerly used for tailings disposal, are being addressed in an enhanced environmental monitoring program to commence in 2000. Changes in water chemistry and the natural re-introduction of aquatic organisms are issues of concern. In the meantime, application for release from selected satellite areas commenced in 1999. This paper reviews the issues which have arisen during the transition phase, outlines how they have and are being addressed, and provides a comparison of original and current predictions of the recovery process under way at the former Beaverlodge mine site.

Jan 1, 2000

By C. H. Bloomster

This study estimated (1) radon and radon daughter emissions from underground uranium mines; (2) the reduction in radon that would be released to the surface by using control techniques such as bulkheads, sealants, backfilling, and positive pressure ventilation; (3) the cost for radon and radon daughter removal from total exhaust air; and (4) total radon and radon daughter discharge for lower occupational exposure limits. For 13 large underground uranium mines, estimated yearly radon emissions from each mine ranged from 900 to 3,400 Ci. The estimated age of air emitted from the mines ranged from 11 to 37 min. Potential radon removal methods for the total mine exhaust were evaluated. The cost of these methods was prohibitive. Diurnal and seasonal changes may affect radon emission over short periods of time, but do not affect the total emissions over the long run. Radon and radon daughter emissions would be little changed by increased ventilation requirements needed to achieve lower occupational exposure limits. The concentrations in the exhaust would be lower, but the total release would be the same

Jan 1, 1984

By D. E. Hulse

"Social License, the consent of the neighbors and community to develop and operate a mine, has received little attention until recently. Though social license is intangible, not having this relationship with the community carries operational and economic risk to a project, potentially including future impairment of the asset. Acquiring and maintaining social license is a long term personal relationship. It requires communication, commitment, consistency, and transparency. This presentation will review the building blocks to acquire and maintain a social license based on experiences with mining projects in Mexico. INTRODUCTION Mining has been a source of controversy for at least 500 years. “Since there has always been the greatest disagreement amongst men concerning metals and mining, some praising, others utterly condemning them” (Agricola 1556). In 2015 it is widely recognized that mineral resources and reserves must give due regard to the social license in order to operate. “Most commonly, the SLO is understood to refer to ‘the ongoing acceptance and approval of a [project] by local community members and other stakeholders that can affect its profitability’ (Moffat 2014).” “Social License to Operate has gained traction, in part, because it is also a concept which – while remaining poorly, technically defined – is generally easily and widely understood by community stakeholders.” (Bice 2014) A generation ago I learned that mining is based on a stable platform supported by three pillars, geology, mining and metallurgy. The three legged stool is a very stable structure.In 2015 it seems that we have added some other legs to the stool. The JORC code addresses “social, and governmental factors” (JORC 2012), and refers specifically to social license in Section 4 of the Report Template “Estimation and Reporting of Ore Reserves”. The Canadian CIM Guidelines refer to “environmental, legal and social data” (CIM 2003).Compared to these the 2014 SME Guide is positively verbose stating “a discussion of any potential social or community related requirements and plans for the project and the status of any negotiations or agreements with local communities,” (SME 2014) although in all cases the scope of this disclosure is left at the discretion of the Competent Person."

Jan 1, 2016

"Guideline Augered Cast-In-Place (ACIP) Pile Specification and Commentary11.0 GENERAL1.1 SCOPEThe Pile Contractor shall furnish all labor, materials, tools and equipment necessary for furnishing, installing and testing Augered Cast-in-Place (ACIP) piles as shown on the Contract Drawings and as specified herein.ACIP piles are commonly referred to by several other names. Some of them are trademarks or service marks owned by Foundation Contractors and some are names that try to describe the installation process. The term “cast-inplace” is sometimes replaced with “cast-in-situ,” especially in Europe. Some common names are Auger Cast Piles, Intruded Mortar Piles, Augerpress Piles, Augered Pressure Grouted Piles, AugerPile Foundations, Continuous Flight Auger (CFA) Piles, Grouted Bored Piles, Augered Grout-Injected Piles, Drilled or Augered Uncased Piles, and Uncased Cast-in-Place Concrete Piles. To avoid confusion, ACIP pile will be used exclusively herein.1.2 PILE CONTRACTOR QUALIFICATIONSThe ACIP piles shall be installed by an experienced Pile Contractor who upon request of the Engineer shall submit evidence of successful ACIP pile installation under similar job and subsurface conditions, including a job supervisor who shall have a minimum of five years of method specific experience.The proper installation of the ACIP piles is dependent upon the procedures used by the Pile Contractor’s field representatives and equipment provided. The Pile Contractor’s personnel responsible for the installation should have relevant experience with the auguring and pumping equipment, experience placing piles under similar site conditions (including restricted headroom if appropriate), in similar subsurface conditions, as well as experience handling the special grout mixes, admixtures, etc."

Jan 1, 2016

By R. E. Murray

"It is a gloomy moment in the history of our country. Not in the lifetime of most men has there been so much grave and deep apprehension; never has the future seemed so incalculable as at this time. The domestic economic situation is in chaos. Our dollar is weak throughout the world. Prices are so high as to be utterly impossible. The political cauldron seethes and bubbles with uncertainty. Russia hangs, as usual, like a cloud, dark and silent, upon the horizon. It is a solemn moment. Of our troubles, no man can see the end." By now you, no doubt, are asking, 'Where did Murray get this bit of philosophy?' Well, I obtained it from an editorial entitled. "The Worst of Times", which was published in the Harper's Magazine in 1847. That's right, 1847! The parallelism between the situation in our country at this time and in 1847 is un- canny. But wait, there is one major exception the size of government. To my knowledge, the citizens of 1847 were not stifled by the extreme governmental excesses that we are experiencing today.

Jan 1, 1980

By Samuel Frimpong

Green house gases have become a major concern within the international community over the last two decades due to their potential link to global warming. Carbon dioxide (CO2) is the principal greenhouse gas. In the Kyoto Agreement, Canada has committed to reduce emissions by 6 % below 1990 levels by 2012. This presents a serious economic challenge to Canada and Alberta. Over the next decade, oil sands production expansion, population and industry growth and energy demand will increase CO2 emissions. Current and future CO2 emissions and their economic implications in Alberta will be critical in formulating a comprehensive and balanced policy for dealing with concerns in this area. Disposal of carbon dioxide (CO2) in land aquifers is a potentially viable option for Alberta in dealing with long-term CO2 emissions. Studies have confirmed the existence of appropriate aquifers in the Alberta Basin for CO2 storage over a long geological period. Carbon dioxide is an ideal candidate for aquifer disposal because of its high density and solubility in water at relatively high pressures. In this study, the authors develop a computer simulation model of a scaled aquifer disposal system. The scaled model consists of an injector well, aquifer environment with dominant Ca++ and Mg++ cations. Liquefied CO2 is injected at an appropriate pressure and concentration through an injector well model. The injected CO2 migrates from the point of contact between the injector well and the aquifer domain to the main regime of the latter. The rate of migration is a function of porosity, permeability, cations, aquifer fluid flow regime and CO2 injected pressure. These models are validated using flue gas data from the 546 MW Wabamum Power Plant in Alberta. The total energy requirements for aquifer CO2 disposal system are distributed between a minimum of 105 MW and a maximum of 172 MW, with a mean of 132 MW and a coefficient of variation of 10%. The results show that there is significant variability in all the energy requirements for the CO2 disposal system. The total energy requirements for the disposal system as a fraction of the total power generated by the Wabamum plant of 546 MW could be between 0.19 and 0.32. This is a very significant energy requirement and thorough analysis must be carried out to reduce this variability and energy requirements.

May 1, 2001

With the iron ore industry in Australia producing hundreds of millions of tonnes of ore per annum, the associated costs of these operations extend into the billions. It is no surprise in the current economic climate that more and more companies are looking into different ways of optimizing their costs to keep their sites operational. One way of improving operations is the use of electronic initiating systems like i-kon and Uni tronic detonators. These systems have been used around the world to improve current practices and optimize drill and blast costs. However, these systems have yet to make an impact upon the iron ore sector in Australia. Some of the potential improvements include:pattern expansion and a subsequent reduction in drilling and explosive costs;improved fragmentation and hence increased dig rates, thereby driving $/tonne down;embracing the 'mine-to-mill' concept by reducing the downstream costs of crushing and milling;improving the overall condition of pit walls and floors, leading to a safer working environment in which optimal haulage performance can be achieved; and improvements in vibration management around heritage sites and critical infrastructure, thereby saving the cost of relocation works. This paper introduces some of these concepts and the process of making the changes leading to potential savings from the improvements, using various examples as proof of the concepts.

Jan 1, 2009

By J. O. Lewis

"The significant facts in the problem of the relation between the production of crude petroleum, and the ever-increasing demand for petroleum products are that in spite of continually increasing production, improvements in methods of refining and utilization, and heavy increases in imports, demands grow still more rapidly and we seem always faced with a shortage at hand or lust ahead. On the other hand, our foremost authorities warn um of entirely inadequate domestic reserves. Looking abroad we find some large fields and many of speculative promise, 'tut the situation is complicated by international relations and demands by other countries which promise to be even more insistent than oars. This is the situation, then. We can not rely upon our own Crude Petroleum to meet the Ever Increasing Demand for Petroleum Products.I wish to follow this somewhat alarming statement by saying at once that the Bureau of Mines is not pessimistic in facing this situation. To my mind those who discuss the oil situation may be placed in three categories; the pessimists, the optimists, and the super-optimists. The pessimists I call those who see darkly and will concede no possibility of solution. According to them a few years will see the automobiles piled in windrows of 'dilapidated junk, I have no sympathy with this point of view and deem it vicious and entirely unwarranted.The optimists I term those who believe that there is a solution and that we shall be able to meet all of our reasonable requirements for as far into the future as can be foreseen, yet who recognizes that this desired end can not be attained without prevision and energetic effort.The super-optimists are those who will say to you, ""There is nothing to this talk of shortage, whenever we have needed oil we have always found it and always will."" To these gentlemen the possibility of an inadequate supply of oil is as incomprehensible as the possibility of the extinction of the passenger pigeon was to the early settlers who saw flocks that hid the sun for days during their passage. The passenger pigeon disappeared within two generations thereafter, and I deem this point of view as being perhaps more vicious than that of the extreme pessimist. It seems to me it is nothing less than improvidence lulling us into a false sense of security. There is an old proverb to the effect that ""The Lord helps him who helps himself."" I believe that we shall solve the oil problem, but I do not think it will be solved by vague optimism. It is going to call for our most energetic efforts and I believe we shall have to do a lot of ""helping ourselves."""

Oct 1, 1920

Jan 1, 1882

By L. A. Jameson, J. Awmack, P. J. Lind

"Peñasquito is a polymetallic deposit containing gold, silver, lead, and zinc. The operation is currently the largest producer of gold in Mexico. Over the next few years, the process flowsheet will be expanded beyond the flotation of lead and zinc to include flotation of pyrite from zinc tails and subsequent leaching of the pyrite concentrate. This paper outlines mineralogical leach characterization that has been carried out to improve the understanding of the complex hosting of gold and silver minerals in the ore. Organic carbon that is present in the ore can have an impact on flotation and leaching. Mineralogical techniques used to characterize this deleterious component of the ore are introduced.INTRODUCTION Goldcorp’s Peñasquito operation is located in the Mexican state of Zacatecas, approximately 200 km from the city of Zacatecas as shown in Figure 1. Peñasquito has been in operation since 2009 and is currently Mexico’s largest gold mine. Mining is carried out by open-pit methods, with oxide ore proceeding to a heap leach facility and sulfide ore treated in the sulfide processing plant.The processing capacity of the sulfide plant is 130,000 tonnes of ore per day and in 2016 production amounted to 450,000 ounces of gold, 17.6 million ounces of silver, 109 million lb of contained lead, and 263 million lb of contained zinc in lead and zinc concentrates. GEOLOGY The Peñasquito deposit is hosted in and adjacent to two breccia pipes; Peñasco and Breccia Azul. The two breccia pipes are branches of a larger intrusive-related complex, which is hosted in the sedimentary Caracol formation as illustrated in Figure 2. The regional geology is dominated by Mesozoic sedimentary rocks which comprise a thick series of marine sediments deposited during the Jurassic and Cretaceous periods. A 2 km thick sequence of carbonaceous and calcareous siltstones and interbedded sandstones is underlain by a 1.5 to 2 km thick limestone sequence (Goldcorp Inc., 2015)."

Jan 1, 2017

By R. L. Bullock

The New Lead Belt of Missouri, situated in the heart of the Clark National Forest, stands as a dynamic example of how mining activities can successfully coexist in a restricted wilderness area. After 16 years of intensive drilling activity, mine development and surface plant construction, many would agree that the mine-plant design philosophy of St. Joe has minimized the imbalancing effects to the ecology and the wilderness appearance of the Ozark area. In a recent dedication speech of St. Joe's newest operation, it was stated: 1 "this Brushy Creek Mine, as well as nearly all of the mines in this district, lies within the boundaries of the Clark National Forest. Here the Forest Service has an outstanding and realistic program for multi-use of Federal lands. Mining, lumbering, recreation and conservation coexist in, what I consider, a delightful wilderness environment. I believe that this same type of usage could be permitted on all government land without seriously detracting from its natural beauty." Each and every activity in the process of discovery, exploration, development and finally operating a mine and process mill could have drastically degraded some phase of nature's environment were it not for the well developed and executed plans of the mining people involved. This is not to say that everything has been kept in perfect balance; but most certainly the industrial impact on what was once a wilderness area has been held to a minimum. What follows is the story of how each phase of this gigantic development was handed by industry people. Through their interaction and cooperation with government agencies, educators and researchers, allowed not only the ecology of the area to be protected, but the aesthetic beauty of the Ozarks to remain intact.

Jan 1, 1973

By Ernst P. Hall

As a scientist and an engineer whose responsibilities include the consideration of air pollution and its control, I am frequently called upon to answer variations of two basic questions, These questions may I be set forth as: (1) How much air pollution does the coal industry cause? (2) How serious is the air pollution problem to the coal industry? At first these questions may seem elementary and almost trite, but serious consideration of them will show that they are technologically involved and I further complicated by the subjective base to which they must be evaluated.

Jan 1, 1963

By Xia Hong-ying, Peng Jin-hui, Zheng Zhao-qiang, Zhang Li-bo

"Preparation of activated carbon from the walnut shell by microwave assisted steam activation was studied. Influences of the three parameters, activation temperature, activation duration and steam flow rate on the adsorption capacity and yield of walnut shell activated carbon(WSAC) were investigated,optimization process was obtained by the Response Surface Methodology (RSM). The optimum preparation conditions were as follows: activation temperature of 980°C, activation duration of 41 min and steam flow rate of 1.66 ml/min. The optimum conditions resulted in an activation carbon with an iodine number of 1025 mg/g and a yield of 52.17%, while the BET surface area, total pore volume and average pore diameter of WSAC were 1328m2/g, 0.72ml/g and 2.2nm respectively. The study supported the potentiality of comprehensive utilization ofWalnut shell and the benefits of the microwave heating.IntroductionActivated carbons are one of the most important adsorbent materials in modern society because of its abundantly developed pore structure, strong adsorption ability, high surface area and thermo stability. They have extensive application in many industries fields which include gas purification [1], catalyst supports [2] and other pollutants [3]. However, in recent years, the industrial production of activated carbon is facing the problem of raw material scarcity and high cost, which limit to be widely used. Therefore, the selection of an appropriate precursor plays an important role and it has become hot sport to seek cheap raw material to lower preparation cost. As a kind of reproducible resource, the waste from agriculture and forestry is a high-grade raw material for preparing activated carbon due to is high carbon content, such as palm shell [4], rice hull [5], and coconut shell [6]. At present Walnut shell is widely accepted to be a renewable source of biomass. According to statistics, there is more than 1000,000 tonnes of walnut shells are produced in China annually [7]. As a good precursor for activated carbon production, Walnut shell is a major agricultural waste, to make better use of the cheap and abundant agricultural waste, it is proposed for activated carbon production."

Jan 1, 2014

By J Hartnett, B Tarrant, A Rayner, D O’Toole, P Davies

Since 2009, the Northern Territory and Australian governments have been working under a national partnership arrangement to inform a rehabilitation plan for the former Rum Jungle uranium mine. Part of the rehabilitation strategy is to backfill a flooded former pit (Pit), which extends down to 100m below the current pit lake surface and was historically partially backfilled with uranium tailings. It is proposed to utilise the remaining pit volume below water level to sub-aqueously store Potentially Acid Forming (PAF-I) waste rock which currently occupies large stockpiles across the site. The rehabilitation design and planning process undertaken to develop a strategy commensurate to project objectives and construction constraints involved the establishment of key constraints derived from the analysis of historic data sources and preliminary design efforts. Tabled strategies were balanced against dependent project tasks and project objectives, especially surrounding minimising disturbance of highly contaminated materials within the Pit. Ideas were developed in conjunction with industry input and review of case histories to develop a remediation solution that is constructible within the project timeframe and constraints.

Jul 1, 2021

By Douglas G. Fox

Outputs from industrial activities planned in the Riley Ridge natural gas project are modeled to determine the potential locations of air pollution impacts on the Bridger and Fitzpatrick Wildernesses in Wyoming. The nature of modeling, especially with regard to its realism, is discussed. Alpine lakes which, along with their watersheds, have minimal buffering capacity are being studied because of their sensitivity to acidic deposition from proposed new air pollution sources. A hypothesis which relates a source's emissions to deposition and lake chemistry in a worst-case sense is presented. Research designed to test the hypothesis and reduce uncertainties is outlined and progress reviewed. Focus is placed on the meteorological transport and atmospheric deposition parameterization contained in the hypothesis.

Jan 1, 1984

By Roger C. Wilmoth

The most common method of treating mine drainage to prevent water pollution consists of neutralization and aeration. This process removes the acidity, iron, aluminum, and some other heavy metals, but does not render a water suitable for domestic or industrial use because of the high dissolved solids, hardness, and sulfate in the treated water. The Environmental Protection Agency (EPA), has been sponsoring and conducting research since 1966 on the use of reverse osmosis (R.O.) for the treatment of mine drainage. This process has been found to be highly effective in the removal of nearly all the dissolved solids. In addition, since R.O. is a concentrating process, potentials for recovery of valuable heavy metals are possible. This paper is a review of the state-of-the-art on the treatment of mine drainage by reverse osmosis.

Jan 1, 1972

By R. L. Nyirenda

The use of ammoniacal ammonium carbonate (AAC) leaching for the treatment of carbon steelmaking EAF dust has been investigated on a laboratory scale. The experiments have been conducted on dust samples obtained from three European steelmaking companies. As received, the dusts were found to be toxic when tested according to current EPA toxicity testing procedures. Toxicity was on account of the leachability of one or more of the following elements: Ag, Hg, Pb, and Cd. Leaching experiments with concentrated AAC solution at 40 " C showed that zinc oxide present in the three dust samples, 60-80% of the total contained zinc, was rapidly solubilized. Data on the dissolution characteristics of Cd, Fe, Pb, Mg, and Mn are also presented. Toxicity tests conducted on residues of the leaching experiments found these to have leachates below past and current EPA toxicity threshold limits.

Jan 1, 1993