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By K. V. Fedotov, E. V. Zelinskaya, O. V. Ulanova

"Mining enterprises, in particular, those on the territory of the Siberian platform, produce large amounts of pumped water, which cannot be recycled because of its high mineralization and, thus, is discharged as liquid waste either back into the ground or onto the surface. However, groundwater is often a valuable raw material and a source of useful chemical substances. Brines are unique groundwaters. In the current environmental and economic situation, the huge loss of natural raw materials and their deliberate conversion into wastes is unaffordable. The exploration of non-traditional sources of minerals such as the hydromineral resources (including pit water) is a matter of rational nature management. The industrial value of brines of the Siberian platform is due to the high contents of rare alkali and earth alkaline elements (lithium, rubidium, cesium, strontium, bromine, etc.). The absolute concentrations of these elements in brines are tens of times higher than the lower limits of the mining cut-off. The long-term data analysis was performed to estimate the environmental impact of liquid waste from two mining enterprises, namely, Korshunovskii (Irkutsk region) and Udachnaya (Southern Yakutia). The study was focused on the prospects of hydromineral resources as non-traditional sources of valuable elements and the exploration of technological processes for the selective extraction of rare alkali and earth alkaline metals from natural multi-component brines aimed at decreasing their negative environmental impact. The environmental and economic efficiency was proved for the processing of complex brines and the integrated selective extraction of rare earth metals from sodium chloride brines of the Korshunovskii plant and calcium chloride brines of the Udachnaya plant based on the ion exchange sorption, eluent chromatography, flotation, crystallization, and freezing techniques. The basic technological schemes were developed for the metal extraction from pit water and brines.INTRODUCTION In the Irkutsk region (the Angara–Lena artesian basin) and in Yakutia (the Olenek and Tunguska artesian basins), several mineral deposits are developed and, incidentally, aquifers bearing brines of different types are opened, which are eventually converted into liquid production waste (Rusetskaya et al., 1994) This raises the issue of the burial or utilization of brines since their use within the water circulation is impracticable under the existing technological conditions while their discharge into the surface watercourse is unacceptable because of the harmful environmental impact."

Jan 1, 2018

By M. L. W. Tuttle, B. R. Berger

Our study focuses on the geology, hydrology, and geochemistry of a variety of molybdenum (Mo) porphyry systems. The systems are either high fluorine, granite, Climax-type, systems (e.g. Mount Emmons/Redwell Mo deposit, Colorado and Questa Mo deposit, New Mexico) or low fluorine granodiorite systems (e.g. Buckingham Stockwork Mo deposit, Battle Mountain, Nevada and Cannivan Gulch Mo deposit, Montana). The water quality of streams, natural springs, mine discharge, and ground water from drill holes were assessed in the region of these deposits. The ultimate goal of our study is to understand the environ-mental behavior of these Mo porphyry systems in the context of geologic setting, hydrologic regime, and climate.

Jan 1, 2004

By E. M. De Souza, J. F. Archibald

This paper examines aspects of Canadian mine backfilling operations that may be implemented to assist in reducing solid waste production, lowering energy costs, and restricting Greenhouse Gas emissions. Many Canadian underground mines use backfill to mitigate environmental effects associated with tailings disposal. Backfill production and disposal are energy intensive processes that require an average energy cost of 37.7 MJ/tonne of backfill to complete. Mine backfills, in engineering applications, also commonly make use of cement as a stabilizing agent. Cement requires an additional energy cost ranging between 4,637 and 6,600 MJ/tonne to produce. The large energy needs associated with mine backfilling and cement production operations create significant CO2 and Greenhouse Gas emissions. Approximately 1 tonne of CO2 and Greenhouse Gas is emitted for each tonne of Normal Portland Cement produced. For single mines producing 3,000 tonnes of backfill per day, considering both backfill and cement emission source terms, total emissions of CO2 ranging between 120.36 tonnes and 169.44 tonnes/day are anticipated. In Ontario, mining operations contribute 700,000 - 840,000 tonnes/year of CO2 and Greenhouse Gas emissions to satisfy backfill cement consumption needs alone. Potential reductions of cement in backfill would significantly reduce emission of these gases and lower their adverse environmental impacts. This paper identifies alternate, equally effective and lower cost binder agent strategies for cement in backfill that may lead to cement consumption reductions. Post-consumer glass represents one such potential alternative backfill binder. Over 950,000 tonnes of glass are disposed of annually in Canada, two-thirds of which exists in the form of easily recoverable glass packaging that is not currently recycled or reused. The partial replacement of cement by waste glass may address goals for reducing non-recyclable glass waste disposal; enhancing mine back filling operations; reducing total backfill energy costs; and ultimately reducing Greenhouse Gas emissions levels currently generated by the Canadian mining industry.

Jan 1, 2004

By D. R. Taylor, R. G. Goss

The use of clay-based granules as carriers for pesticides dates back to the early 1940s. It now represents a business conservatively estimated at between 180 and 270 kt/a (200,000 and 300,000 stpy) in the United States alone. Prices for these materials typically range from $110 to $165/t ($100 to $150/st). Aside from economic and specific target pest efficacy advantages, the use of clay granules as pesticide carriers also delivers a number of environmental benefits, which are reviewed. Topics discussed include drift control (vs. liquid sprays), mobility (in the environment), worker safety and transportation (spill) safety.

Jan 1, 2000

By D. R. Taylor

The use of clay granules as carriers for pesticides dates from the early 1940's and by the present day represents a business conservatively estimated at between 200 -300 thousand tons / year in the U.S. alone. Aside from economic and specific target pest efficacy advantages, the use of clay granules as pesticide carriers also delivers a number of environmental benefits which will be reviewed. Topics to be discussed will include: I) drift control (versus liquid sprays), 2) mobility (in the environment), 3) worker safety, and 4) transportation (spill) safety.

Jan 1, 1999

By D. R. Taylor, R. G. Goss

The use of clay granules as carriers for pesticides dates from the early 1940's and by the present day represents a business conservatively estimated at between 200 - 300 thousand tons / year in the U.S. alone. Aside from economic and specific target pest efficacy advantages, the use of clay granules as pesticide carriers also delivers a number of environmental benefits which will be reviewed. Topics to be discussed will include: 1) drift control (versus liquid sprays), 2) mobility (in the environment), 3) worker safety, and 4) transportation (spill) safety.

Jan 1, 1999

By A B. Richards

Effective control of blast vibration and flyrock requires that significant factors be identified and quantified, that the blast be designed to ensure both blasting efficiency and compliance with applicable limits, and that the blast design be effectively implemented by field personnel. Significant factors contributing to ground vibration and airblast are: charge mass; distance and direction relative to the blast; drilling design: burden, spacing; stemming height and material type; hole diameter and depth; and initiation sequence and direction.In addition, airblast may be strongly influenced by shielding and meteorological conditions. Ground vibration is also influenced by the transmission characteristics of the ground and soil. Flyrock throw is determined by charge mass, burden, stemming height, blasthole diameter and depth. The contribution of each of the factors has been quantified and models developed to enable the environmental outcomes of blast design to be predicted. Environmental blast design is necessary to ensure compliance with regulatory limits and the implementation of æsafeÆ exclusion zones for flyrock clearance. This paper discusses the models used for environmental blast design and demonstrates the often significant effects that lapse during implementation of the design can have on predicted outcomes. In practice, drillers and shotfirers are sometimes confronted with situations that require modifications to the blast design to cope with the real site situation. Methods are presented that may be used by drillers and shotfirers to evaluate the effect of these modifications, the tolerances that must be reached during their work practice and checking procedures, and the consequences of their actions.

Jan 1, 2004

By Richard E. Danell

"Blasting is a principal step in the surface mining process for breaking and, in the case of overburdencasting, moving rocks and minerals. As many surface mines are coming to the end of theiroperational life, blasting can once again play an important role through the earthmoving operationsrequired to rehabilitate the minesite. Since blasting is such an energetic and destructive process, itis difficult initially to envisage its use in rehabilitation. However, blasting has found applications inmany civil engineering projects aimed at rehabilitation, including well digging, channelling and soilcompaction. For surface mine rehabilitation, the main purpose of earthmoving operations is toproduce a stable landfonn that will sustain revegetation. In particular, blasting can be applied toreducing the slope of steep walls left by quarrying and open pit mining through a modified form ofthe overburden casting technique. Blasting can also be applied to breaking up pit floors andbenches to speed and improve revegetation of these areas (subsoiling)."

Jan 1, 1994

By R. Flatabø, K-E. Johansen, L. Hunsbedt, P. M. Cowx, J. A. Bustnes

Eramet and Tinfos are two producers of manganese alloys in Norway, which have worked hard for several decades to improve both the internal and external environment. Furnaces producing ferro- and silico- manganese alloys generate large amounts of off-gas that contains substantial amounts of dust, heavy metals and organic by-products. The dust is separated from the gas in venturi scrubbers by washing with water. The water is cleaned and recirculated, and the surplus water coming from moisture in the raw materials, is discharged to the adjacent fjords after further treatment. Emission figures show that the discharge of suspended solids, manganese, zinc and PAH (polycyclic aromatic hydrocarbons) have been reduced substantially over the last three decades as a result of process improvements and installation of state of the art environmental control measures. The two plants were the first world wide to install mercury cleaning of the off-gases from the furnaces. Mercury emission reduction has exceeded 90%. Concerning other environmental issues, such as utilisation of off-gases for energy recovery and chemical purposes, both plants have achieved good results. Major effort in the environmental work has come from the plants themselves, but other players like FFF, The Norwegian Ferroalloy Producers Research Association, and SFT, The Norwegian Pollution Control Authority, have contributed to the achieved results.

Jan 1, 2007

The mining industry is an important economical factor in Vietnam. Mining is presently being conducted at about 60 locations and at over 1000 mines. Petroleum extraction and coal mining are the most important parts of industry though metals such as zinc, tin, chromites, iron are also extracted. Last year the sector produced 20 million tons of crude oil, 26 million tons of coal and 500,000 tons of apatite. In particular, Vietnam is one of the world?s largest producers of anthracite, and it is one of the top producers of ilmenite and zircon in the Asia-Pacific region. The government intends to increase the mining production on all levels, however, at present one can observe adverse impacts of the mining activities on the natural environment such as insufficient waste dump rehabilitation, occurrence of acid mine drainage, mining subsidence and emissions as well as lack of appropriate water treatment facilities. This paper describes the current mining situation, future perspectives, the major environmental challenges of the country and approaches to solve these problems. Particular emphasis will be given to the research project ?RAME ? Research Association on Mining and Environment in Vietnam?, a venture carried out by universities, research centres and industry. This project is worked out in collaboration with the national Vietnamese coal and industrial minerals company VINACOMIN.

Jan 1, 2006

By T. Thriveni, Ji Whan Ahn

"The current advanced technologies for the manufacture of light weight metals processing significantly increasing and attributes to the safety, performance, recyclability and economy. Still lack of technologies developed for light weight metals processing waste utilization and application. Environmentally friendly methods need to develop for better understanding the processing waste utilization. Alumina and aluminium processing creates a wide range of waste products, the most significant being is red mud. Bauxite residue is a high volume hazardous waste and nearly 3 billion tons have been dumped worldwide. Approximately, 120 Million tons/yr of red mud being produced without any environmental sustainable solution. Currently the most significant technology is waste utilization. The bauxite residue is suitable for road base construction, golf bunker sand, back fill and, general fill. Sustainable recycling technologies are necessary for the bauxite residue utilization for the recovery of rare earth elements and cement materials. Carbonation or CO2 sequestration of carbon dioxide is a method pioneered for the bauxite residue is modified to reduce alkalinity. The carbonation of alkaline material is an inexpensive and safe process that leads to the formation of thermodynamically stable products. The use of the carbonation can be an advantageous solution for environmental climate change and sustainability problems in the new century.INTRODUCTIONIn 2014, bauxite consumption was estimated to be 9.6 million tons, nearly all of which was imported, worth an estimated 269 million dollars. More than 95% of the bauxite was converted to alumina, and the remaining 5% went to non-metallurgical products, such as abrasives, chemicals, proppants, and refractories. Global aluminum demand is growing steadily spurred by growth in India and China (RBCAluminum Market Outlook, 2013) (Figure 1). Aluminum consumption is expected to rise 5% annually through the end of the decade, reaching 67 million tons per year by 2020. Global bauxite production decreased by 17% from that of 2013, principally owing to lower production in Indonesia. In response to a Government ban on exporting bauxite and other unprocessed mineral ores that took effect on January 12, 2014, bauxite mines throughout Indonesia shut down and production decreased from 55.7 million tons in 2013 to an estimated 500,000 tons in 2014. The ban was part of a mining law that was instituted in 2009 to increase development of downstream processing facilities in Indonesia."

Jan 1, 2016

By Randall E. Brown

Irrigation simulates a climate change so that crops can be grown that otherwise would not thrive. The abundant sunshine and warm weather of many arid regions induces a rate of growth in excess of that in cooler, moister regions. Hence, the arid part of eastern Washington, traversed by the Columbia River, is admirably suited to irrigation. The Pasco Basin lies in south-central Washington at the south end of the Columbia Basin Irrigation Project of the U.S. Bureau of Reclamation. The Basin, because it lies in the rain shadow of the Cascade Mountains, receives only 6 to 10 inches of precipitation a year with somewhat greater amounts, commonly as snow, on the higher hills. Recent extremes included 3 inches of precipitation from August 1967 to August 1968, and 12 inches in the succeeding "12 months. Most of the precipitation falls during winter. If it were to fall in summer or were evenly distributed throughout the year, evaporation rates probably would produce a true desert.

Jan 1, 1971

By Davey FJ

The Hikurangi Margin of eastern North Island New Zealand represents the feather edge of the over-riding Indo-Australian Plate at its convergent boundary with the subducting Pacific Plate. Towards the south, convergence becomes slower and increasingly oblique, and sediment supply from the Southern Alps becomes increasingly rapid. In this environment a 150 km wide, imbricate thrust, accretionary prism has grown since the Miocene, uplifting slope ridges and basins and a range of coastal hills. Offscraping of thick, axially transported, trench-fill turbidites begins in a zone of proto- thrusts, which extends up to 25 km beyond the principle, slope-toe, deformation front. On the slope, landward tilted, trench-slope basins are separated by ridges. The ridges ride up on thrusts that sole out at a major decollement. The decollement dips landwards at 3 degrees to a depth of 14 km at the coast, where it coincides with an onshore zone of high seismicity. Beneath the decollement, about 1 km of consolidated, oceanic sediment is going under the margin with the underlying oceanic basement. Some of these sediments may underplate the frontal ranges to the west and geochemical evidence of subducted sediment is found in the volcanic zone beyond. A rapid decrease in the width of the accretionary prism to the north is associated with a decrease in sediment supply and perhaps with a dislocation in the downgoing plate. To the south, the accretionary prism narrows, swings westward, and merges into the zone of very oblique collision that marks the transform between mirror image subduction to north and south of New Zealand.

Jan 1, 1987

By Ta M. Li

In Gila County, Ariz., the Jaquays Mining Co. still finds the mining of asbestos a worthwhile and economical venture. At a time when domestic productive capacity is being reduced because of rapidly rising costs and tough environmental dust standards, this firm has dramatically brought its mine and mill operation into full productive capacity and compliance with both Federal and State regulations. Jaquay's Mining Corp. owns four underground mines in the Tonto National Forest, located approximately 32 miles north of the Globe-Miami District in Arizona. Only one mine, the El Dorado, is presently active. It mines an estimated 45,000 tpy of ore and waste. From this figure about 3000 tpy of fiber (No. one crude to Grade 4T) and fiberized shorts (No, seven) are recovered at the firm's mill, located in Globe, Ariz. Based on current ore reserves, the El Dorado mine has an estimated life between 15 to 17 years, assuming current mining rates and stable market conditions.

Jan 3, 1975

By Conrad Parrish

As originally conceived, this paper was to address the costs of environmental compliance, focus on environmental impact statements, and describe how those costs impact mining projects. The intent was to do wide ranging mathematical analyses to demonstrate the varying impacts on mining projects depending on their size, timing, return on investment and other salient project features. The initial portion of the numerical analysis necessary to this purpose was performed. The results showed a pattern of impacts familiar to the mining industry:

Jan 1, 1991

By Nicholas Matthews, Vilem Petr

This project will report findings on the establishment of a new surface test site at the Colorado School of Mines Edgar Mine. Concerns over the blast effects on site neighbors prompted the study to be conducted. The current maximum charge weight of 20-lb was studied to ensure that all environmental effects were within the range prescribed by state and federal regulations. Geophone locations were surveyed using GPS and monitored using Instantel Minimate Plus instruments. Distances and orientation of measurement sites to the test site were varied according to the local geography and geology. Weather conditions were also observed and recorded during all tests. Neighbor complaints were recorded and taken into account during analysis. Current results show that the current charge limit results in a safety factor of over 200 for all blasting activities at the site. Data collection is ongoing and a review is to be conducted annually. These results will be presented in the future. Results are presented and discussed in the following paper. Copyright

Jan 1, 2010

The passage of a vast array of new State and Federal environmental legislation over the last couple of years has required many mine operators to sharpen their focus on environmental requirements. Established requirements, such as environmental impact assessment, minimising disturbance and rehabilitation must now be complemented by mine environmental management plans. These may not only require regular monitoring of mine operations and detailed forward planning to prevent or reduce environmental harm caused during mine operation, but annual updating. It is likely that in future these plans will be required to incorporate general principles such as pollution prevention, sustainable development, waste minimisation and conservation of biodiversity and ecological integrity.

Jan 1, 1993

By Thomas E. Brown

With the ever increasing public sensitivity to our environment, the blasting industry can no longer be concerned with just drilling and blasting. Government regulations, augmented by public pressure, require that the industry must be more diligent in preventing spills, disposing of distressed products and packaging materials, controlling fumes and dust, preventing product contamination, developing environmental impact studies, and preventing unnecessary regulations. These liabilities in conjunction with those of vibration, air overpressure and flyrock will continue to greatly impact the industry.

Jan 1, 1995

By J. M. Hans, M. F. O’Connell, G. E. Eadie

INTRODUCTION The U.S. Environmental Protection Agency (EPA) was required, under Section 114(c) of Public Law 95-604, to provide a report to Congress identifying the location, and potential health, safety and environmental hazards of uranium mine wastes together with recommendations, if any, for a program to eliminate the hazards. The approach taken to prepare the report was to develop model active and inactive mines and locate them in a typical mining area to estimate their environmental impact. A list of uranium mines was acquired from the U.S. Department of Energy (DOE). The inactive mines were separated from the list and sorted into surface and underground categories. A literature search was conducted to obtain and consolidate available information concerning the environmental aspects of uranium mining and shortterm field surveys and studies were conducted to augment this information base. Radioactivity emission rates were measured or estimated for each mining category and were entered into computor codes to assess population exposures and subsequent health risks. The general environmental condition of inactive uranium mines was determined by walk-through surveys in several mining areas. INACTIVE SURFACE MINES We assumed that a model inactive surface mine contains a single pit with the wastes (overburden and sub-ore) stacked into a pile adjacent to the pit area. No credit for reclamation is given to the model mine. In lieu of the availability of individual mine production statistics, the model surface mine size was established from the total ore and waste production statistics for all surface mines, divided by the number of inactive surface mines. The number of inactive mines, obtained from the DOE mine listing, are summarized by type and location (Table 1). For modeling, we assumed that there are 1,250 inactive surface mines. The total or cumulative waste and ore production for inactive surface mines from 1950 to 1978 is not fully documented. Uranium mine waste and ore production statistics, on an annual basis, were available for both surface and underground producers from 1959 to 1976 (D0159-76). Annual uranium ore production for each uranium mining type are available for 1948 to 1959 (DOE79) and for combined ore production TABLE 1. Consolidated list of inactive uranium producers by State and type of mining [State Surface Underground AL 0 9 AZ 135 189 CA 13 10 CO 263 902 ID 2 4 MT 9 9 NV 9 12 NJ 0 1 NM 34 142 ND 13 0 OK 3 0 OR 2 1 SD 111 30 TX 38 0 UT 378 698 WA 13 0 WY 223 32 Total 1246 201T] for underground and surface mining from 1932 to 1942 (DO132-42). In order to estimate waste accumulated prior to 1959, the waste-to-ore ratios from the 1959 to 1976 period were plotted vs. time and line-fitted by regression analysis (Figure 1). Unfortunately, the extrapolation of the line to years prior 1959 approached zero in 1954 although surface mining began in 1950. Therefore, a waste-to-ore ratio of 8:1 was used for the period of 1950 to 1959 based on ratios estimated by Clark (C174). The waste to-ore ratios for 1976 to 1978 were estimated using the line established in Figure 1. By using waste-to-ore ratios and ore production data, the cumulative waste and ore production for both surface and underground uranium mining is estimated to 1978 (Table 2). The estimated cumulative waste from uranium surface mining for 1950 to 1978 is 1.73 x 109 MT. A crude estimate of the waste accumulated at the model inactive surface mine can be made by dividing the total waste produced to 1978 by the number of inactive mines. This, however, overestimates the waste tonnage because some of the contemporary wastes are being produced by active mines, and the waste accumulated at newer mines has increased in recent years. To adjust for this overestimate, we assumed that all mines operating in 1970 will be inactive by 1978. This eight year period is approximately one-half the lifetime of a model

Jan 1, 1981

By David White

THE environmental conditions under which coals are deposited are revealed by the stratigraphy of the coal basins and coal beds and by the details of the structure and the physical constitution of the coals themselves. THE LAND SURFACE Generally Low Relief or Base Level In the Paleozoic coal fields, which have longest been worked, are most important, and are best known, we find relations, in general, as follows A post-Mississippian uplift with, in most cases, very moderate deformation, followed by erosion by which the uplifted regions, especially the bolder of the new topography, were largely worn down, while the older and less deformed regions were more or less extensively base leveled. Base leveling of most of the region continued as the deposition of coal measures proceeded. Consequently, in most coal fields the Pennsylvanian, or upper Carboniferous, lies unconformably on the Mississippian or on older formations. There are but few regions in which sedimentation is seen to have been apparently continuous from the Mississippian into the Pennsylvanian ("Coal Measures").

Jan 1, 1925