Search Documents

A decision by joint-venture partners Anglo American, Gencor, and the Industrial Development Corporation to proceed with the expansion of the Columbus Stainless Steel plant in Middelburg will contribute significantly towards the economic growth that South Africa needs so desperately. The expanded facility, expected to come on-line in 1995, will be the largest single-plant producer of stainless steel in the world, and the company will rank sixth overall in world production.

Jan 1, 1993

By J. L. Jambor, M. J. Baker, M. J. Logsdon

"Abstract - Prior to the development of the Diavik Diamonds Project, baseline studies were conducted to determine the geochemical characteristics of four kimberlite orebodies as an aid in the design of both the water-management system and the facilities for containment of processed kimberlite and ore stockpiles. Materials tested included field samples of volcaniclastic and pyroclastic kimberlite, processed kimberlite (i.e., kimberlite ore which had been screened and washed as part of the processing procedure), and sedimentary mudstone (a minor xenolithic unit which was assimilated during kimberlite emplacement). Approximately 200 samples of kimberlite materials were collected as part of the geochemistry program. Test-work included whole-rock chemical analyses, acidbase accounting, kinetic leach tests using columns, and mineralogical analyses. Diavik kimberlite has major oxide and trace-element concentrations consistent with global averages for kimberlite. The mean total-sulfur content of the kimberlite material is 0.22 wt% S, but with a significant range. The kimberlite has an excess of carbonate minerals over sulfide minerals (average CO2 = 4 wt%, present mainly as calcite), and has a mean neutralization potential of 311 kg CaCO3 equivalent/tonne. A reactive form of framboidal pyrite associated specifically with the mudstone xenoliths is the primary source of sulfide-sulfur. Long-term kinetic tests confirmed the preliminary interpretations that were made from the static-test results. Kimberlite and processed kimberlite are net acid-consuming materials that produce alkaline drainages and have low but detectable leaching rates for SO4 and specific trace metals such as Al, Co, Cu, Ni, and Zn. If segregated from the kimberlite, mudstone xenoliths are acid-generating (pH = 3) and produce an effluent with elevated concentrations of SO4, Fe, Al, Cu, Ni, and Zn. The study demonstrates that xenolithic units in Diavik kimberlites have an important effect on the environmental geochemistry of the ore rock. The mineralogy and aqueous geochemistry of the kimberlite materials are such that they may not be suitable for general earthworks or as an alkaline agent and should report to an engineered facility to protect site water quality."

Jan 1, 2001

By P M. Ashley, M Muller

Massive sulphide ZnPbCuAg deposits in the Halls Peak district of north-eastern NSW are of the submarine volcanogenic type. They occur as a number of small lenses enclosed in shale and epiclastic rocks, in association with felsic volcanics of early Permian age. The deposits crop out in steep terrain near the eastern edge of the New England plateau. Local relief of 700 m and slopes up to 50¦, coupled with an average annual rainfall of about 1000 mm has led to local severe land sliding in previously mined areas. Mining from the 1890s to the 1960s has also resulted in unconstrained drainage of heavy metal-bearing acid waters and physical dispersion of finer grained metalliferous sediments into the Chandler River. Waters emanating from the main landslide area, from underground workings and draining scattered unconfined stockpiles of massive sulphide ore have pH values of 3 to 4 and contain elevated contents of Zn, Cu, Pb, Cd and Fe. Chemical mobility of heavy metals into streams occurs under low pH conditions with Zn exhibiting the greatest dispersion. Increasing pH conditions downstream cause precipitation of Fe phases and coprecipitation of heavy metals. Physical dispersion of secondary metal-bearing minerals into the surrounding creeks results in wt% levels of Cu, Pb and Zn in the stream sediments thereby exceeding the regional background values by one to three orders of magnitude. Areas disturbed by mining are characterised by lack of vegetation, biomagnification of heavy metals into algae and lower plants, and partial recolonisation by metal-tolerant grass species (Snow Grass, Poa sieberana; Blady Grass, Lomandra longifolia). Rehabilitation measures will have to include landslide stabilisation, impervious sealing or removal of sulphidic materials, import of topsoil and revegetation by metal-tolerant, slow-growing native grass and shrub species.

Jan 1, 1995

By Muller M, Ashley PM

Massive sulphide ZnPbCuAg deposits in the Halls Peak district of northeastern NSW are of the submarine volcanogenic type. They occur as a number of small lenses enclosed in shale and epiclastic rocks, in association with felsic volcanics of early Permian age. The deposits crop out in steep terrain near the eastern edge of the New England plateau. Local relief of 700 m and slopes up to 50¦, coupled with an average annual rainfall of about 1000 mm has led to local severe landsliding in previously mined areas. Mining from the 1890's to the 1960's has also resulted in unconstrained drainage of heavy metal-bearing acid waters and physical dispersion of finer grained metalliferous sediments into the Chandler River. Waters emanating from the main landslide area, from underground workings and draining scattered unconfined stockpiles of massive sulphide ore have pH values of 3 to 4 and contain elevated contents of Zn, Cu, Pb, Cd and Fe. Chemical mobility of heavy metals into streams occurs under low pH conditions with Zn exhibiting the greatest dispersion. Increasing pH conditions downstream cause precipitation of Fe phases and coprecipitation of heavy metals. Physical dispersion of secondary metal-bearing minerals into the surrounding creeks results in wt% levels of Cu, Pb and Zn in the stream sediments thereby exceeding the regional background values by one to three orders of magnitude. Areas disturbed by mining are characterised by lack of vegetation, biomagnification of heavy metals into algae and lower plants, and partial recolonisation by metal-tolerant grass species (Snow Grass, Poa sieberana; Blady Grass, Lomandra longifolia). Rehabilitation measures will have to include landslide stabilisation, impervious sealing or removal of sulphidic materials, import of topsoil and revegetation by metal-tolerant, slow-growing native grass and shrub species.

Jan 1, 1995

By Bruce W. Downing, Philip G. Claridge

"The availability of environmental data is a major concern in the development of an exploration project through the permitting and feasibility stages. The collection of these data should ideally start very early in a major exploration program. Although a large proportion of the environmental data can also be used for exploration purposes, (e.g. stream-sediment, soil, and rock analyses), environmental sampling will rarely have been initiated at an early date. For the Windy Craggy project, a major environmental concern is the potential for generation of acid rock drainage from waste-rock piles. The project is reviewed with respect to the environment of the deposit, deposit geology, mineralization and reserves, the sequence of exploration activities to the present, the potential for the development of acid rock drainage, the geochemistry and water quality, and the integration of exploration and environmental databases and their application to environmental planning. IntroductionIn the classical sense of exploration of a mineral deposit, the efforts throughout exploration are routinely directed at confirming the existence of the deposit and defining its extent, grade and continuity. Environmental issues are usually tackled separately, possibly by different personnel at a later date. When that is the case, an opportunity is lost to build, from an early date , a comprehensive database that (I) will satisfy the needs of conventional exploration and environmental monitoring, and (2) is usable as a predictive tool for environmental impact assessment.The concept of environmental geochemistry is not complex. The availability of environmental data is a major concern in the development of an exploration project to the feasibility and permitting stages. The collection of data should ideally start very early in any major exploration program. In many cases a significant proportion of the geochemical exploration data gathered early in the life of a project will also be used later for environmental purposes (e.g. stream-sediment, water, soil, and rock analyses). Rarely, however, will the data gathered in a geochemical exploration program provide information as complete as that attainable if environmental objectives had been considered in scoping the work.A knowledge both of local and regional geochemical processes can lead to a better understanding of environmental impacts. This understanding is the basis upon which good environmental management practices may be built. Geddes Resources Limited has undertaken a major study of the natural environment in the Windy Craggy area which includes geology, surface and underground waters, soils, stream sediments, glaciers and geomorphology (Geddes Resources Limited, 1990). This paper deals with the building and integration of the exploration and environmental databases."

Jan 1, 1993

By J S. Kuszmaul, T O. Aspinall

The applicability of environmental geotechnics for erosion management is increasing in importance worldwide. The environmental impact of mining and evolving environmental legislation has been receiving increased attention worldwide in the last two decades (Bradfield, Shultz and Stone, 1996). The potential impacts associated with unstable spoil dumps from mine operations is the focus of concern both by the mining industry, environmental legislative agencies and members of the public. This is because of the need to increase the reliability of erosion prediction and in the minimisation of costs for spoil dump design. Engineered slopes of mine spoils may be stable at the end of construction, but they can deteriorate over time. Engineering design of mine spoil dumps seeks to reduce the potential for such erosion damage through correct selection of an initial stable landform scheme (Goh, 1997). The design of mine spoil dumps must also conform to the specifications of evolving legislation. The Queensland Environmental Management Overview Strategy (EMOS) states that, for minimised degradation of the surface area due to erosion during the development of a project, the erosion rates should be between 12 - 40 tonnes/hectare/year and that the depths of rills and gullies be limited to less than 30 cm (QDPI, 1988). The aim of engineering design is to ensure the long-term stability of the spoil dumps. The implementation of effective planning and operating procedures through recontouring and grading assists in the reshaping of spoil dumps to a safe, stable and non-erodible environment.

Jan 1, 1998

By Jack E. Thompson

I have spent my entire life in the mining industry pursuing what I believed was an honorable profession that provided products that were critical for our social and economic well being. Now I am told that all of my efforts been for nothing and that I have been doing something morally wrong - mining. This view of the future is not one that the mining industry has to allow to unfold. A determining factor in how things will turn out is continued improvement of the industry's environmental performance. To some extent, the current state of affairs in the United States is a result of the common perception that greedy corporations (usually foreign) are somehow ripping off US citizens of their native birthright or natural treasures in the name of corporate profits. Implicit in this view is the belief that corporations will take shortcuts or violate the environment in the name of profits. I have 26 years of experience in working in the copper, uranium and gold industries. Profits during those years were meager and difficult to find (Fig. 1). In fact, when I began working fresh out of college, I chose copper, which was then selling at around $1/lb. By the time I left copper mining, it was selling for 45 cents/lb. I then moved to uranium, which was selling for $52/lb. By the time I left it was $16/lb. I finally picked gold, which was then at ($650/oz). There is a whole generation of engineers, geologists and professionals who have spent two decades downsizing, closing mines, improving costs and getting smarter about how the mining industry does what it does. The environment, health and safety are areas where there have been great improvement. There are five characteristics of corporate governance that are critical for a company to develop and an industry to embrace if environmental, health and safety excellence is to reach new heights in the labor pool.

Jan 1, 1997

South Africa?s now a member of this body, tailored on the World Bank, and headquartered in Abidjan-Cote d'Ivoire. As a funding agency for capital projects within 59 member countries of the ADB it is to be expected that there are guidelines to the requirements for funding application and for project management and control.

Jan 1, 1996

By W. G. Dallas

The social and environmental problems presented by the location of a large zinc/ lead ore body within one mile of a thriving town are described. The development problems are social, involving the education of the in habitants , and environmental, requiring the development of a planning strategy and the evolution of a baseline and post -operational monitoring system. The necessity for an environmental-impact assessment and a thorough baseline study is emphasized. The continuing psycho-social consideration of community reaction is advocated.

Jan 1, 1977

In all the industries that require blasting operations using explosives, there exists numerous unwanted side effects of the blast which may pose as environmental hazards. These hazards face prominence, especially in India, where there are very stringent rules and regulations governing the use of explosives. The environmental hazards associated with blasting operations as a whole can be tacked successfully to a certain extent depending upon the ultimate expectations of ,the post-blast effects and the limitations of the environmental obligations as specified by the authorities from time to time and from place to place. The main parameters which require attention to limit the post-blast results to the optimum level are ground vibrations, dust pollution, gas pollution, air blast effects, noise pollution & fly rocks etc.

Jan 1, 1995

By Raja V. Ramani

Discussion in this section of the Handbook is limited to the working environment of miners, the mine workers themselves, and the machines used in mining (Fig. 11.0.1). The contents emphasize personnel health and safety aspects and engineering design and control practices to ensure a productive health and safety environment. Reference is to the health and safety of the individual miners as well as to the safety of the working environment. This Handbook also contains references to health and safety regulations in Chapter 3.2 and environmental protection in Chapters 3.4 and 7.3.

Jan 1, 2008

By T. E. Kobrick

When Ralph Banks called and asked if I would agree to present a paper on environmental health in the coal industry, I was reluctant because I have not been actively involved in coal mine dust control on a day-to-day basis for a number of years. Ralph reminded me that I am one of the few industry people with an industrial health background who remembers the pre-1969 Federal Coal Mine Health and Safety era. This marks the second time within the past year that I have had a similar request based on the same basic reasons. While I was pleased to have been remembered, I'm beginning to feel like the football player who has played one too many games. In responding to Ralph's request to present an overview of the past, present and future of environmental health in the coal industry, I have attempted to take the broad approach of someone who, having been intimately involved in an area of endeavor for a number of years and then leaves, has an opportunity to revisit that area at a later date to see what has changed and what remains the same, what have been the successes and the failures. Since none of us can foresee the future, trying to project too far ahead is fraught with frivolity, except that unless one is foolish enough to accept a future invitation to review those predictions compared to actual events, no one will recall how accurate or inaccurate those projections might have been. I can assure you that I will not ask to accept that challenge, so you can rest comfortably that five years from today you will not be asked to sit through a similar presentation by me - and that's a promise.

Jan 1, 1985

By G. L. Hohmann

The Waste Isolation Pilot Plant (WIPP) project is authorized by legislation to provide a demonstration of the safe disposal of radio- active wastes generated by the national defense programs and activities of the United States. The U.S. Department of Energy (DOE) is proceeding with the implementation of the WIPP project in accordance with the "Department of Energy National Security and Military Application of Nuclear Energy Authorization Act of 1980" (PL 95-164).

Jan 1, 1982

By Longworth C. R

Competing requirements for land usage sometimes make the correct all- ocation difficult. The decision can be complicated by many factors such as local resident pressure, previous government decisions, economic pres- sures and the duration or permanency of the competing land usages. This problem often confronts the extractive industries with consequent delays in granting leases and some- times considerable local dissension. A proposal to extend the high grade silica sand quarry of the Wamberal Sand Company Pty. Limited is a microcosm of these competing requirements. The sand quarry is located on the New South Wales central coast. It is an open pit operation on a near beach deposit of silica sand suitable for flint glass manufacture.

Jan 1, 1976

By B. Farshadi, B. Asi, M. J. Habibian

"In this paper, the most significant environmental aspects that are identified in the Taft Copper Project (TCP) are the quality and quantity of water, pollution of the existing watercourses and post-mining land use, matters such as air and noise pollution are deemed to be of less significance. Analysis has been performed for Do Nothing Alternative, Pre-stripping Phase, Mining Phase, Closure and After-use Phases. Analysis of the environmental assessment of TCP was carried out in three stages. In the first stage, the general negative and positive aspects of the project were identified. In the second stage the intensity, magnitude and significance of the environmental impacts of the project were identified. The third stage is related to the final conclusions of the assessment team and the relevant reasoning. A modified Leopold Matrix was adopted for evaluating the significance and magnitude of the environmental impacts. For this project, the matrix was modified to allow the assessor to take account of negative and positive numbers."

Jan 1, 2011

By Guy Xueyi

The environmental impact assessment of the Imperial Smelting Process for metallic zinc and lead production in Shaoguan Smelter, China, was carried out by the life cycle assessment method. The detailed inventory analysis of the Input/Output in the process during 1998-2000 was conducted and the allocation was done among the main products of zinc, lead and sulfuric acid, according to the system expansion and substitution principle, The environmental impacts were assessed by using the following five Eco-indicators: Gross Energy Requirement (GER), Global Warming Potential (GWP), Acidification Potential (AP), Heavy Metal Toxicity' (HMT) and Solid Waste Burden (SWB). The results from this study are useful to address the environmental situation of the technology practice in this smelter, and provide a scientific basis for the further improvement.

Jan 1, 2003

By Verónica Fernández, Jaime Solari

"The Chilean Environmental Impact Assessment System (EIAS) of investment projects was created in 1994, date in which the General Environmental Law was enacted. The compulsory environmental approval of projects began in 1997 when the Regulation (S.D. 30/97) was officially issued. By beginning late to regulate the environmental effect of investment projects, Chile could take advantage of the international experience in the matter and therefore, the EIAS has many of the attributes of successful environmental assessment systems elsewhere. Thus, the main characteristics of the Chilean EIAS are: preventive, single-window, specific to certain projects, multi-agency assessment at the regional scale, 3 kind of applications, deadlines, citizen and native communities participation, link to relevant permits, definite conditions of approval/rejection, review of applications by an ad hoc institution. The Chilean EIAS has allowed during the period 1997-2013, the review of 21,110 projects for a total investment value of US$ 408 billion, of which a 76% have been approved. In the case of the mining projects, the corresponding figures for the similar period are 1,257 projects for a total investment value of US$ 119 billion, of which 78% projects were approved. The experience derived from the environmental impact assessment of mining projects indicates that Chile has been successful in linking together mining development with environmental protection. There is still little prejudice against mining and this is a still a largely welcome economic activity at all levels in the relevant regions of the country. The challenge that mining companies face today in Chile is to improve the sustainability of projects and operations, by learning to share scarce and valuable resources (water, glaciers, renewable energy) with the local and native communities, through a process of dialogue whereby mining development also generates benefits for these communities."

Jan 1, 2014

By M. Popescu

In the southern part ?f the Occidental Carpathians an iron ore body embedded in crystalline schist was exploited. The presence of minerals such as magnetite, pyrite, pyro-chorine, allanite, monazite and xenotime, which also include within their structure substituted thorium isomorphic, was pointed out. The iron ore was processed by crushing, grinding and magnetic separation in order to obtain magnetite concentrates. The environment was affected by pollution generated by the mining activities. In 1995 due to the economic reasons, it was decided to cease mining exploitation and remediate the area. The paper presents the ecological impact caused by mining activities on a number of environmental targets and the population. The pollution sources, namely sterile dumps and mine waters are characterized (from the physical, chemical and radiometric point of view); the pollution pathways and theirs effects on potential targets, namely soil, vegetation, hydrographic network and population are identified as well. The degree of pollution due to all sources was assessed and maps of pollution sources distribution were generated. The supplementary effective doses for the population were assessed using rigorous scenarios and considering all exposure pathways. The rehabilitation plan includes solutions for dumps geometrization, covering and revegetation as well as mine waters management.

Jan 1, 2005

By S. Triantafyllidis

The tailings produced from the Kirki (Agios Filippos) high sulfidation epithermal deposit processing plant are laminated, weakly cemented and their particle size ranges from fine sand to fine silt. They are mainly composed of milling residues of gangue (quartz, dickite/kaolinite, pyrophyllite, illite); sulfides and secondary minerals (jarosite group minerals, butlerite, anglesite, beudantite and gypsum) are present to a lesser extent. They have high Pb and Zn (average 0.75 % and 0.57 % respectively) and low S (1.04 to 2.92 %), Cu, As, Cd, Ni and Sb content (average 248, 163, 59, 27, 20 g/t respectively). Stagnant waters forming small ponds on the surface of the impoundments exhibit low pH and high heavy metal and sulfate concentrations. Negative Net Neutralization Potential (NNP) characterizes the tailings, indicating moderate to high potential for acid generation. Application of the TCLP test revealed that the tailings are characterized as toxic because of the increased solubility of Pb and Cd. On the other hand, As TCLP solubility is very low.

Jan 1, 2006

By D. -P. Georgescu

A native sulfur mineralization associated with pyrite and iron oxides containing 20% iron was quarried in Calimani Mountains, Oriental Carpathians. The wastes resulted from this exploitation activity, with a volume of 33 millions m3, were stored in four dumps while the wastes resulted from ore processing using flotation and the subsequent treatment were disposed of in a settlement pond. The investigations carried out in the entire mining area focused on the following two aspects: - the impact of environmental factors mainly on the hydrographic network; - the characterization all pollution sources, namely dumps, leachates and the quarry and the assessment of acidic drainage generation. The total sulfur content of the excavated ore was 3.8% while in dumps it ranged between 0.54 and 1.06%. Analysis of samples collected along the hydrographic network, draining the mining area, resulted in pH values ranging between 1.7 and 2.83 as well as high concentration of iron (4525 mg/L to 1.6 mg/L), copper (1.87 mg/L to 0.04 mg/L) and zinc (13.13 mg/L to 0.3 mg/L). Samples from the quarry, the dumps and the tailings pond were analyzed in order to deter-mine: - the maximum potential acidity (MPA); - the acid neutralization capacity (ANC); - the net acid production potential (NAPP).

Jan 1, 2005