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By W. L. Oliveira, J. R. Sobrinho, V. M. Hamza, S. M. Eston

The Ipueira III chrome mine is located in the northeastern part of the state of Bahia, Brazil. Extraction is actually at depths less than 300 m, but below level 200 serious environmental problems have been encountered with respect to control of air quality, toxic gas, dust and thermal comfort. At the request of the mining company the University of São Paulo started a research program to investigate the origin and occurrence of the critical problems and to propose solutions. A ventilation survey was carried out first which revealed the existence of several air leakages and short circuits that contributed to substantial reductions in the air supply to some of the main producing levels. Computer simulation of the ventilation network showed that extending the intake air shaft to deeper levels was the most convenient and economic solution to improve the air quality. The ventilation survey was followed by a mapping of the toxic gas emissions and thermal comfort levels in several parts of the mine. The air quality conditions were evaluated as a function of gas emission and heat generation associated with production and development activities. The results show that environmental conditions are already critical in most of the working levels and neither an increase in production nor deepening of the mine can be taken up without substantial changes in the ventilation system. INTRODUCTION Environmental concern is growing in Brazil and several underground mines are starting environmental engineering programs. The LACASEMIN - Laboratory of Environmental Control and Mine Safety of the Mining Engineering Department of the University of São Paulo - was contacted by Mineração Vale do Jacurici to start a research program for investigating the origin and occurrence of environmental problems that existed in the Ipueira III chrome mine. This research program involved field measurements of air quantities with gas levels monitoring, evaluation of heat stress parameters, determination of adequate flow patterns through computer simulations and training of mine technical staff. This paper presents the results of the first 4 months of this research program. The Ipueira III mine is located in the northeastern part of the state of Bahia, near the city of Senhor do Bonfim at about 400 km inland from the state capital city of Salvador. Chromite mineralization is quite widespread in this area and often associated with mafic and ultramafic rocks which cut across regional gneisses and migmatites. ROM production in 1992 varied between 25,000 to 40,000 tons per month, 25% being of lump type (38% of Cr2O3) and 75% being of fines. Lump is manually separated and fines are concentrated in a nearby plant. All the production goes directly to the group processing steel plants near Salvador. The Ipueira III mine is currently under some adverse economic situation because of imports from South Africa and Russia, which have better grades and sometimes a lower content of phosphorous. Consequently there has been little progress in the development of new mines and even in those currently under operation the extraction is becoming more difficult due to the lack of investment in improving mining methods and ventilation systems. In spite of such difficulties the company has backed up studies for initiating an environmental engineering investigation of the Ipueira III mine. MINING METHODS AND VENTILATION SCHEMES The mining methods adopted have changed as a function of extraction depth, rock mass strength and ore body geometry. Initially the orebody was found to be fairly continuous and dipping at about 55 degrees from surface

Jan 1, 1993

By P. Schmieder

"The close vicinity of mining companies to other sites that are used for commercial and residential purposes or to areas under conservation as well as the fact that the people become more and more sensitive to emissions have led to a negative attitude towards mining operations in the neighborhood. It is above all the use of drilling and blasting techniques that give rise to objections, in the course of which demands for more environmentally-friendly production methods have been voiced. It is in this context that production methods without the use of explosives are considered as an option. After all, the use of such production methods is the only alternative for some quarry operators. The question is what are the true benefits of these techniques and what is the relation between a possible improvement of the environmental effects on the one hand and the technological potential as well as the costs on the other. It is intended to assess the mining techniques for solid rock in their entirety. This paper will therefore look at the aspects for assessing mining techniques in the context of their environmental impact and the costs."

Jan 1, 2005

By A. D. Davis, C. J. Webb, C. S. Johnson

The Belle Eldridge Mine is an inactive lead-zinc mine in Spruce Gulch south of Deadwood, South Dakota. Acidic mine drainage (AMD) produced at the site drains into Spruce Creek, a tributary of Whitewood Creek. The site is on U.S. Bureau of Land Management (BLM) property. Extensive fieldwork was done at the Belle Eldridge Mine through the cooperation of the BLM and the South Dakota School of Mines and Technology. The site was extensively mapped to identify physical and environmental hazards such as tailings, waste rock, collapsed buildings, adits and workings. An exhaustive search of the historical records of the Belle Eldridge Mine was conducted. Maps of the under-ground workings of the Belle Eldridge dating from the 1930’s and 1940’s were found. The maps were used to correlate currently collapsed features to old adits and tunnels. Using hand corers and a portable drill rig, waste rock, tailings and soil core samples were collected and depth to bedrock was determined and the total volume of waste and tailings pile were determined. Related work examined the hydrology of the site. The site is very complex hydrogeologically. Numerous underground and surface workings and tunnels add to the complexity. Several seeps are located at the site, one of which is producing AMD. Recharge to the site was studied, and a 100-year flood plain map was produced.

Jan 1, 2000

By J. M. Pachter

Property sales and acquisition are prominent features of today's coal industry. Before selling or buying a site, a company must know the property's economic net worth. Any evaluation of economic net worth would be inadequate if determinations of a property's environmental liabilities and costs were omitted. Short-term and long-term costs can result from liabilities related to reclamation, water treatment, subsidence, and hazardous waste disposal. A structured, interdisciplinary approach can aid in the delineation, summation, and scheduling of these costs and liabilities.

Jan 1, 1986

The Environmental Excellence in Exploration (E3) project is driven by the recognition that the minerals industry can only maintain its long term viability by ensuring its continued access to lands to explore for, and develop, new mines. Widespread implementation of sound environmental management practices by the exploration community and improved education and understanding of that by stakeholders will help substantially in accomplishing this, and E3 is designed to meet these needs. Exploration crews are now viewed as ambassadors for the global mining community. Their performance in managing the environmental aspects of an exploration program can demonstrate a commitment on the part of the international mining sector to environmentally responsible exploration and mining. We have all observed that failure to behave responsibly can alienate local residents, encourage anti-mining NGOs and jeopardize development. As the saying goes, ?you don?t get a second chance to make a first impression?, and we want to make a favourable first impression. The E3 project is focused on creating an electronic manual, the e-manual, which will provide rapid access to the most up-to-date information on environmental management practices for minerals exploration globally. The e-manual will reflect current thinking and practices in environmental management. It will be richly illustrated with actual examples that reflect the realities of exploration. It will strive to identify the key environmental issues and concerns that apply to most exploration projects, and identify other sources of relevant information useful to field practice. It is our belief that E3, or something very like it, is central to ensuring that the industry survives the current challenges to its viability. E3 will be a cornerstone of the mining industry?s drive to sustainability simply stated, if we are not permitted to explore for mines, there will be none of them at some point in the relatively near future.

May 1, 2002

By J. P. Jarrell

Environmental considerations are of increasing importance in determining the acceptability, schedule and cost of expansion ofCanada's uranium processing industry. Environmental considerations must be addressed in the early stages of facility planning. This results in a dilemma, as the process data needed to predict physical environmental impacts are not yet available from process design activities. Hence, a business risk is incurred if plant design is carried forward to meet these requirements prior to project (or site) approval. On the other hand, project scheduling normally mitigates against leaving process design engineering until such time as project approval is obtained. This paper examines the experience gained in Eldorado Nuclear's proposed expansion of refining capacity as viewed by an environmental engineering consultant. The history of the project and the relationship to process design functions in the two-year period prior to the Port Granby environmental hearings are reviewed. During the Port Granby public hearing, there was a consensus that normal operation of the proposed refinery could be successfully integrated with the site's natural environmental constraints. Moreover, the radiological impact from plant operations was demonstrated to be inconsequential. However, concerns were raised relating to plant upset and accident situations. These concerns are summarized. Process data requirements identified during the environmental hearings are discussed. Finally, the concerns for on-site burial of radioactive waste are reviewed. These concerns focussed on long-term stability of the waste in the presence ofgroundwater transport, erosion and glaciers. The AECB's position on waste management with regard to this project is reviewed in light ofthe implications for design.

Jan 1, 1979

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 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 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

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 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 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 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

By Guo 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