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By Z. T. Bieniawski

Results of in situ investigations are discussed providing comparisons of rock mass deformability measurements by three methods: 'petite sismique' technique, the Goodman borehole jack and flat jacks. The tests were performed in exploratory tunnels constructed for site characterization purposes of an underground hydro-electric scheme. Due to the large number of data (41 petite sismique measurements, 45 Goodman jack tests and 19 flat jack measurements), it was possible to evaluate thoroughly the testing techniques employed. The purpose of this paper is to indicate the problems encountered in the interpretation of the results and to offer suggestions for selecting in situ tests. INTRODUCTION In situ tests are expensive and time consuming but they are an important aid in tunneling applications since they can provide deformability data of rock masses in contrast to rock material characteristics obtainable from small laboratory specimens. Some in situ tests are relatively easy to perform but their reliability may be in question unless a comparison of the data obtained by several different test methods is possible. Although many in situ techniques are available for determination of rock mass deformability (1), those more convenient to use are the Goodman jack, flat jacks and 'petite sismique. These methods are considered convenient because the Goodman jack is a borehole device; flat jacks can provide not only deformability data but also information about the stress field around excavations; while 'petite sismique' is based on seismic refraction surveys. Accordingly, these three methods have been selected for comparison.

Jan 1, 1979

By J. Smolensky, M. Paul

The Nordhalde is a waste rock pile resulting from uranium mining near Ronneburg, Germany. The pile contains over 27 million m3 of waste rock. Typical seepage water has a pH of 2.7 and a sulfate concentration of 10,000 mg/L. Geochemical investigations of the Nordhalde from 1993 to 1996 included drillholes, test pits, ABA and metals analyses, column tests, and a detailed review of the construction history of the pile. In 1996, eight drillholes were instrumented for monitoring oxygen and temperature. Monitoring continued for a fill year. Hourly temperature and pressure readings were taken by automated data recorder. Oxygen concentrations were measured three times per week, and periodic gas samples were obtained for complete analysis. The resulting data set is believed to be one of the most comprehensive of its kind. Effects noted elsewhere, such as thermal convection, are evident. However, unlike other data in the literature, the NordhaIde data shows a strong seasonal effect, with convection dominating oxygen transport only in the winter months. Analysis of the data allowed the amount of contaminants associated with ongoing and historical oxidation to be compared, and results were used to assess the potential effectiveness of proposed remediation measures.

Jan 1, 2000

By Julián Ortiz C., Clayton V. Deutsch

Indicator simulation allows specification of different continuity of high and low values through the use of grade thresholds. The sequential implementation of indicator simulation has been widely used, but the problem of order relation deviations remains a significant drawback. A new procedure for "Hierarchical Indicator Simulation" is introduced that avoids order relations and offers greater flexibility than the conventional sequential approach. The new implementation simulates all locations at the largest threshold and then considers decreasing thresholds in turn. All nodes with grades that are above the previous threshold are excluded from the domain of the current threshold and therefore, they are not used as conditioning data. The probability of being above or below the threshold is calculated using simple indicator kriging using all conditioning data in the domain, thus the covariance structure is preserved. The theoretical framework of this new approach is fully developed. Practical implementation details are discussed. Application to a copper deposit shows the advantages and drawbacks of the method. Finally, the possibility of incorporating multiple-point statistics is discussed.

Jan 1, 2002

By H. Fayed

Two-phase (water and air) flow in a self-aspirated WEMCO flotation machine has been investigated using computational fluid dynamics (CFD). The geometric model is a replica of a 300 m3 cell. A 72-degree sector containing two blades of the ten-blade rotor has been modeled and periodic boundary conditions are applied in the circumferential direction. Simulation of a sector of the machine allows acceptable resolution of the mean flow field using 4x106 grid points. The flow is modeled by Euler-Euler approach, and transport equations are solved using a commercial software ANSYS-CFX5 [1]. Unsteady simulations have been performed. In a self-aspirated machine, airflow rate is not known a prior; it is an output from the CFD simulation. Uniform mean bubble diameter of 0.7 mm has been specified as an input for the simulation. Air flow rate and power consumption have been monitored with time, and results indicate a stable operation. Air volume fraction contours and velocity field in different regions of the machine are presented and discussed.

Feb 27, 2013

By T. N. Moore, E. M. De Souza

Vibratory hand-tools can produce Hand Arm Vibration (HAV) Syndrome in their operators. This disease, often called Vibration White Finger, can cause varying levels of hand-arm discomfort and, in severe cases, impairment. In addition to the human suffering, there are also significant economic repercussions for industry. These include reduced operator efficiency, lost time through increased absenteeism and increasing compensation awards. In the mining industry, jackleg rock drills are a particularly troublesome source of hand vibration exposure. As a result, a significant amount of work has focused on redesigning rock drill handles to minimize hand-transmitted vibration. This paper details the results of a study undertaken to determine the effectiveness of using elastomer covered ("cushioned") handles in place of the standard steel design. The results indicate that, for a particular cushioned design, the overall acceleration level experienced at the hand-handle interface can be reduced by as much as a factor of three, relative to the steel handle. It is also shown that this reduction takes place predominantly in the frequency range above 500 Hz, with performance improving with increasing frequency. Qualitative evaluation of the cushioned handles by the drill operator indicates a significant increase in comfort over the standard steel handle.

Jan 1, 1992

By D. Malhotra, R. M. Hoover

The effect of a surfactant, designated Syntex, on the wetting and spreading of hydrocarbon oil on molybdenite surfaces (faces) has been investigated experimentally through measurements of zeta potentials and factorially designed flotation tests. These studies indicate that Syntex has a positive effect in increasing molybdenite recovery in the rougher flotation circuit at the Climax mill. The analysis of experimental data using DLVO theory shows that the controlling factor in determining the magnitude of the repulsive energy barrier preventing oil from wetting and spreading on the molybdenite faces is the MoS2 zeta potential and the vapor oil droplet size. The role of Syntex in this case seems to be related to the decrease and stabilization of MoS2 zeta potential by Syntex adsorption and also to the emulsifying action of Syntex on vapor oil to provide a more favorable oil particle size.

Jan 1, 1976

By L. A. Romo, J. A. Ferrer

INTRODUCTION The principle line of the Caracas Metro is located generally along the most important east-west traffic corridor of the city from the yards and shops in Propatria at the western extremity to Petare, and eventually beyond to Palo Verde at the eastern end, a route distance of 21 kilometers. There will be 23 stations along the alignment, underground, at grade and elevated, and the line is forecast to handle 1,209,100 passengers daily by the year 2000 with a travel time of 29 minutes between Propatria and Petare. This principle line was divided into three sections for design purposes: Propatria-Fuerzas Armadas, Section I, Fuerzas Armadas-Chacaito, Section II and Chacaito-Petare, Section III. These sections were further subdivided into subsections for construction purposes. The Venezuelan Government, through its Caracas Metro Office in the Ministry of Public Works, awarded design contracts in sections to PARSONS BRINCKERHOFF-TUDOR-BECHTEL for Propatria-Fuerzas Armadas, Section I, OCOIDESA-GRID-APM for Fuerzas Armadas-Chacaito, Section II and OCOIDESA GRID-APM for Chacaito-Petare, Section III. Construction contracts were awarded by international bidding and work is now underway, by joint venture organizations of Venezuelan and foreign firms. The first two sections are under the administration of a company of Engineer/Inspectors in each section. The construction supervision of contracts in the first section is under the administration of the Venezuelan firm, Gómez-Celis-Herrera, (GCH) Engineers, acting under contract to the new C.A. Metro de Caracas that replaced ' the former Office of the Metro. The Propatria-Fuerzas Armadas section, approximately seven kilometers long, consists in part of the 2,951 linear meters of twin-bore

Jan 1, 1979

By J. B. Hiskey

INTRODUCTION The extraction of gold and silver from ores, concentrates, and various metallurgical products can be achieved by a number of hydrometallurgical techniques. The solvation properties of alkali cyanide solutions on gold and silver were recognized 200 years ago. A cyanidation process for leaching gold from its ore was patented in 1887 and 1889 by MacArthur and Forrest. The solvent action of thiosulfate on gold and silver was observed over 100 years ago. Recently, several patents have been issued for processes using ammonium thiosulfate as lixiviant for precious metals, Berezowsky, et. al (1978) and Kerley (1981). Tozawa and and coworkers also examined the dissolution of gold in ammoniacal thiosulfate solution. Thiourea leaching of gold and silver initially discussed by Plaksin and Kozhukhova in 1941 but has received only limited attention since that early work. Use of thiourea as an alternative to cyanide was the topic of several papers presented at the 1981 AIME annual meeting In Chicago, Illinois. Hiskey provided a review of the fundamental chemistry of the dissolution of gold and silver in acidic thiourea solutions. Pyper and Hendrix reported on the leaching of a finely disseminated gold ore using thiourea as a lixiviant. The review article(6) previously presented was fairly comprehensive covering Important contributions to the chemistry of thiourea and the processing of gold and silver with acidic thiourea solutions. A search of the technical literature was made to determine recent (since 1981) progress and developments in applying thiourea to the processing of gold and silver. This review reveals that Soviet and Eastern European scientists are continuing to make major contributions to our understanding of thiourea/precious metal systems.

Jan 1, 1984

By John K. Adams

Phosphorus may be incorporated into sedimentary rocks in at least four different ways: (1) by the accumulation of detrital mineral fragments, (2) by the accumulation of phosphatic organic debris, (3) by diagenesis and (4) perhaps by the primary precipitation of calcium phosphate. Based-on the petrographic examination of Cretaceous and Tertiary sediments from the northern and central parts of the Atlantic Coastal Plain, Diagenesis is the most important of these mechanisms. Both syndiagenesis and epidiagenesis are required to explain the origin of all the diagenetic phosphate mineral species which occur in the northern and central parts of the coastal plain. Syndiagenesis produced much of the coastal plain's apatite. It was operative below the sediment-water interface while the substrate was being compacted. Compaction forced pore waters, which were enriched in phosphate by the decomposition of organic matter, upward through calcareous sediments. The PO43- radicle replaced the CO23- and calcareous nodules, pellets and shell fragments were converted to apatite. Epidiagenetic reactions occurred in the subaerial environment where downward percolating meteoric waters carried phosphate in solution to cites where cation activity was sufficiently high to form new minerals. Vivianite may form where ferrous iron is available and wavellite and variscite may form in the presence of aluminum rich minerals. Textural evidence suggests that many of the reactions were repeated. The present day appearance of apatite, vivianite, wavellite and variscite in the coastal plain may represent several generations of diagenesis.

Jan 1, 1972

By Carl G. Bock

INTRODUCTION Rapid transit systems involving near surface tunneling in hard rock are becoming more numerous, especially along the northeast corridor of the East Coast. Tunneled systems are under construction in Washington, D.C. and are being planned for Atlanta, Buffalo and Baltimore. Near surface tunneling is defined for this paper as being that in which the crown is 100 feet or less below ground surface. For Rosslyn Station, the total cover ranged from 52 to 70 feet. The rock cover, however, ranged from 40 to 50 feet which is slightly less than the station height and about two-thirds of its width. Rosslyn Station (Fig. 1) is the only station excavated completely in hard rock in the Virginia portion of the 98.5 mile Washington Metropolitan Area Transit Authority's (WMATA) rapid transit system. The station site, oriented in a north-south direction beneath a main thoroughfare and flanked by multistory office buildings, was fixed by the need to serve a dense population center at a specific location and geologic conditions were a secondary consideration in siting. There was no previous underground rock excavation in the Washington Metropolitan Area of the size and scope of Rosslyn Station that offered a practical case history guide to the geologic conditions and excavation problems to be encountered. GEOLOGY The regional geology of the Washington Metropolitan Area is divided into two physiographic provinces by the northeast trending Fall Line (Fig. 2). Northwest of this boundary is the Piedmont Province

Jan 1, 1974

By Richard P. Curtin, Madan M. Singh, Francis S. Kendorski

INTRODUCTION The use of roof and rock bolts to reinforce the strata is an established method of rock support in both underground and surface excavations. However, the need to drill a hole, extract the drill-rods, and then place the bolt is time-consuming and costly. This becomes even more significant if the bolting is repetitive and extensive as in coal mining. Though the main thrust of this development was directed towards coal mining, the basic concepts are also widely applicable to all excavations. The authors, therefore, feel that this innovation should be of interest in rapid excavation and in tunneling. In the case of coal mining, it has been established from past statistics that the roof-bolting operation is the most hazardous activity. This is primarily because of the operator being exposed to unsupported ground. It is evident that remote installation of roof bolts would markedly improve the safety of the operation, if accomplished more readily with self-drilling bolts rather than the conventional two-step variety operation. Thus, in addition to increasing productivity, this development can be considered to be a milestone towards further improvements. The objective of this program was to establish the technical and economic feasibility of self-drilling roof bolts for use in coal mines. It might be clarified at the outset that this work was, therefore, directed primarily at showing that workable self-drilling bolts with less cost can be developed, which could be effectively used in mines. It was not to fabricate a production model bolt.

Jan 1, 1979

By P. K. Sharma

The acidophilic and chemolithotrophic Thiobacillus ferrooxidans bacteria grown in the presence of soluble ferrous ions and solid substrates (sulfur, pyrite and chalcopyrite) as their energy source have been used in the investigations. The cell surfaces are characterised by zeta-potential, contact angle, FT-IR and FT-Raman studies. The adsorption isotherms of the cells on pyrite and chalcopyrite indicate that the adsorption begins on pyrite at a much lower equilibrium cell population than on chalcopyrite. The isotherms tend to level off at a cell adsorption density corresponding to a horizontal monolayer coverage when the geometrical dimensions of the cells are considered. In the presence of cells, the xanthate flotation of pyrite completely depressed, whereas chalcopyrite flotation is unaffected. The results suggest that chalcopyrite can be selectively floated from pyrite, also at a neutral pH region, in the presence of T. ferrooxidans cells.

Jan 1, 1999

By A. W. Khair, S. S. Peng

Discussion by J. Parker Gentlemen; Rainy day in Upper Michigan, a good time to catch up on reading. Am doing that, and have a couple of questions concerning the K and P paper on roof problems and supports. I wonder if the authors can enlighten me. The compressive strength of the coal was reported as 4.4 MPa (633 psi) and compressive stresses measured in the coal seam were reported at around 27.6 and 48.2 MPa(4000 and 7000psi ). Can such a soft coal actually contain such a high level of stress? Can it be measured as if the material were elastic, or does the coal behave plastically? Can that stress level be confirmed with hydraulic load cells? And if the coal is so soft, and if it is plastic, why is the stress field not hydrostatic'? The intact roofrock appears to be unusually strong, with compressive strength reported at around 145 MPa (21,000 psi), and some failures were noted as soon as the rock was exposed. Were tests run to find out how that rock responded to the addition of moisture, from sprays or from humid air? Did moisture weaken the rock? Did it cause the rock to expand quickly, thus to induce internal compressive stress? How can the near-vertical cutters, as shown in the photographs, be attributed to primarily horizontal stresses? Did the cutters follow any particular pattern in the development panels, which might be related to a particular stress pattern? For example, did they always appear alongside the stiffest pillar? Or always along the northwest rib? Was there any evidence of the pillars and entries "rotating" under the influence of differential horizontal stresses? How much did the entries and pillars rotate as the longwall face approached and passed? After rooffalls, did the openings assume shapes which would indicate a preferred shape in that stressfield and geology? Did crosscuts always survive without damage, as shown in the sketch?

Jan 1, 1992

By Mark C. Holton

The mining industry has recently been. - experiencing a difficult period. Escalating costs, lower grades and deeper level mining, are a few of .the reasons' why interactive graphics or CADD (computer aided design and draughting) systems are increasingly being used. CADD systems which support powerful and flexible mining applications have great potential for making all forms of mining more efficient and effective. There are many application programs which address almost every aspect of mining. Most of these programs originated to satisfy a particular need. Graphics and other features were added until they, reached a point where they were commercially viable as a mining package. Because of their evolution these packages, lack many CADD-type features. Today there are powerful personal computers (PC's) and engineering workstations running the best CADD systems available. These systems, support hundreds of applications in almost every discipline. Mining was until recently not well supported by interactive graphics vendors because of the highly variable nature of mining and the lack of common standards. Users of CADD systems have experienced the benefits of CADD and come to expect similar features from graphic mining packages. Several developers of mining packagers have either attempted to include some CADD features or make their packages compatible with one or other CADD system. Mining can benefit greatly From a combination of interactive graphics (or CADD) and the right mining application software.

Jan 1, 1989

By R. S. Shoemaker

It is said that there is nothing new under the sun and this is certainly true about refractory gold Ores. Ores which have been refractory to treatment have been the bane of the Metallurgist's life ever since gold has been recognized as a metal valued for its indestructability, malleability and beauty. Webster's Dictionary defines "Refractory" as; "Resisting control or authority, stubborn, resistant to treatment or cure, unresponsive to stimuli, difficult to corrode or draw out," And gives as a synonym the word "unruly." I don't think any metallurgist would disagree with these definitions as they quite accurately describe refractory gold ores as we know them and I wouldn't be a bit surprised if many of you in this room today had applied far stonger language to your own refractory ores in the course of your metallurgical test programs. Pliny the elder put it very well when he wrote in 79 A.D., Gold is the first of man's follies, Silver the second." Perhaps Pliny was speaking of "unassayable gold" or "incipient gold." These are truly refrac tory ores which probably existed before Pliny's time and although many people have claimed to have solved their metallurgy the untold wealth that lies within them has never been bankable. On the other hand, Virgil is his Aenead, could very well have been speaking of refractory ores when he wrote; "Quid non mortalia pectora cogis, auri sacra fames!" which translates as, Accursed thirst for gold! What doest thou not compel mortals to do. Certainly, gold was extremely rare at that time because it had to be recovered by much labor from the then refractory ores and their refractoriness caused the early metallurgists (or alchemists if you will) to seek an easier way to produce it; thus the long and fruitless search for the "philosopher 's stone" which would aid in turn-

Jan 1, 1990

By Z. Man, X. Zhu, Y. Xian, Y. Tao

"Fine coal separation has been always concerned. The froth flotation is not efficient in desulfurization because of the low rate of sulfide liberation from raw coal, the natural hydrophobicity caused by sulfur concentration on the surface of sulfide, and the presence of large amounts of middling feed. An efficient centrifugal gravity separator was employed to separate for Shandong –0.5mm high sulphur coal, the partition curve of centrifugal separator was obtained with conclusion that the Ecart probable error value of the separator is 0.095, the imperfection I value is 0.128. Finally, comparing with the coal flotation using progressive release method, the result shows that the effect of the desulfurization with centrifugal gravity force field based on density difference between coal and minerals are much better than that of the floatation which operates based on the difference in surface properties. It provides a efficient technical way for fine coal separation. INTRODUCTION Coal plays the most important role in the energy consumption in China. Although natural gas, wind energy, nuclear power has made great progress in recent years, but the share of coal in the final energy consumption accounts for 70-80%, which is determined by energy storage of China. Under the requirement of environmental protection, the clean utilization of coal resources becomes more and more important, and the need has already been identified. Coal washing and processing plays an important role in the process of high-efficiency and clean utilization of coal. For the separation of fine coal, flotation is a traditional method for effective separation and has been used in large scale industrial applications in coal preparation plant. However, for the separation of difficult-to float coal, especially fine oxidized coal and low–rank coal with hydrophilic surface, flotation is usually inefficient [1-3]. Although many pretreatment methods have been adopted, including grinding, microwave pretreatment, new flotation reagents, the problem of efficient separation has not been completely resolved [4-6]. Thus, an enhanced gravity separation method using particle density difference rather than hydrophobic difference was proposed for the separation of fine coal. Many research results have proved that this is a practical and effective method of sorting. R.Q. Honaker used Falcon C10 concentrator, Knelson centrifugal separator and spiral separator to clean the fine coal with size of 600*210 µm and 210*37µm, the effects of different operating parameters on the separation index was discussed. The results show that the separation density of Falcon can reach 1.6, and the Ep value can reach 0.1-0.15. This paper revealed that for the separation of fine coal with high sulfur content or fine grained content. Falcon has high separation efficiency with low cost. Separation results present in another paper showed that the desulfurization efficiency of inorganic sulfur was better than that of flotation [7-8]."

Jan 1, 2017

By S. Tuylu, D. Adiguzel, A. Bascetin, H. Eker

"Tailings can be more stable in-site where they are stored and and so the risk of conventional tailings dam accidents can be reduced by alternative methods. In recent years, surface paste disposal (SPD) method is one of the alternative tailings storage methods. According to the results obtained from the previous lab scale experiments, optimum storage design was determined and then, this design was carried out in-site application under atmospheric conditions by a pilot scale tests. In the field study, two separate dams with no environmental hazards were established by the hazardous waste storage directive, whose surface area is measured as 400cm × 200cm. Also physical changes in the paste tailings were measured by the sensors such as volumetric water content, mutric suction and oxygen consumption. In addition, seepage water was collected in the drainage pool and examined for acid mine drainage and metal mobilization risks. As a result of the preliminary data obtained from measurements of pilot scale tests, when the pH value of seepage in the cemented dam (only 1th and 10th layers with cemented) is about 11, the pH value of seepage in the uncemented (reference) dam is measured at 8-9. INTRODUCTION Environmental damages occurred during the deposition of mine process tailings at surface using conventional methods (tailings dam etc.) can be reduced and/or eliminated with the use of new technologies and methods to an important extent. Nowadays, it has been investigated to safely deposit metal mine wastes generally discharged into surface tailings dams, seas, rivers, creeks etc. using Paste Tailing Technology which gains the growing importance in recent years. Meanwhile, Paste Tailings Technology has two applications in industry as an underground paste backfill and surface paste deposition. Particularly scientific studies about deposition of process tailings as paste sample in underground and surface have been increased. These studies showed that surface paste deposition can minimize the free water amount which is the biggest problem in conventional tailings dams. Additionally, it also provides less particle segregation, in other words, the formation of more homogenous material, the development of geotechnical properties which causes to obtain more stable material, increases the strength and stability of the paste with addition of binder where necessary surface paste material, and reduces the risk of Acid Mine Drainage (AMD) (Bascetin et al., 2017a). Theriault et al. (2003), Martin et al. (2006) and Simms et al. (2007) reported that Bulyanhulu mine in Tanzania is the first gold mine to employ surface paste disposal (SPD) worldwide. Here, tailings are deposited alternately via several towers. The tailings flow away from each tower to forming a conical deposit. Each layer had a lower thickness than 30 cm. The fresh tailings were poured on top of drying and hardening layer after a waiting period of 5-30 days. No cement was added into the tailings to prepare paste material. Uncemented paste was deposited by a solid content of 73% which corresponded to a 250 mm slump cone height (Yilmaz et al., 2014). In a study conducted by Yilmaz (2010) illustrates the preliminary results of a field cell testing undertaken to investigate the effect of in situ climate conditions and material properties on the performance and quality of fine-grained, sulphide-rich paste tailings at the LaRonde mine in Quebec, Canada. A total of two field cells are constructed in the surface disposal site of the mine and categorized as cemented cell CC and uncemented cell UC (Bascetin et al., 2017b)."

Jan 1, 2018

By B. Schimm

Improve the mines productivity by simplifying the mining process, for these tasks the Wirtgen Surface Miner offers an attractive alternative. Surface Miners cut, crush and load material in one operation with only one machine. The cutting depth is controlled exactly.

Jan 1, 1997

By H. H. Murray

Recently developed clay deposits that will impact regional and world markets are described. These deposits, their location, geology, and physical properties are delineated. Kaolins from the State of Para in Brazil and from Ukraine; bentonites from Argentina and India; and palygorskite and sepiolite from China are world class deposits that when processed using modem technology will produce excellent products. Other deposits that may affect regional markets are l<aolins from China, Australia and Indonesia; bentonites from Georgia (formerly USSR) and China; and palygorskite from India and Ukraine. New ball clay deposits that will affect regional markets are in China and Indonesia.

Jan 1, 1999

By A. Delgado-Jiménez, O. J. Restrepo-Baena, G. Aristazabal

"Mining industry as a source of raw material is essential to society however, it lacks of good reputation due to the type of management historically applied to many of its social and environmental impacts. It is argued that this situation has hampered the obtaining of social license to operate of a lot of mining projects around the world. The last considerations are very common in Latin American countries. As a result, the mining sector has understood that the viability of the business long term is associated with more profit for the shareholders but also with activities that improve the livelihoods of local communities, enhance the capabilities of local governments and preserve the ecosystems around the projects. Nevertheless, recent studios have shown that most of the current advances to incorporate sustainability concepts in mining have been mainly focused on control and the prevention of environmental and social impacts of extractive activities. Thus, contributing to the development of territories around mining projects constitutes a fundamental aspect of the business competitiveness through reducing cost and risks of stopping projects, innovating new ways of relationship with stakeholders, improving the level of reputation of the industry as well as its position in the market. However, this contribution requires formal strategies and models that enable companies understand the different resources in the territories where their mining activities are developed and those resource transformations, in order to establish the best way to articulate the project with the territory, pursuing an effective contribution to its development, truly sustainable over time even after the mine closure. CONTEXT Currently in the world but especially in developing countries such as Latin Americans, different stakeholders are increasingly vigilant of how mining companies carry out their activities in terms of socio-economic and environmental management of territories, not only for its impact on the livelihoods of the communities that inhabit them, but also because many demanders of raw materials -both countries and companies- have set sustainability standards as a prerequisite to establishing business relationships with mining companies, such as the recently declared Sustainable Development Goals by 2030 (UN, 2015). Accordingly, decide underinvest or not to invest in sustainability issues carries risks for mining companies. However, invest much in the wrong way may involve the same risks. Managers are concerned to ensure profits, and therefore they decide carefully how to invest in the areas of production, R & D or marketing. Likewise, they should think strategically about investing in initiatives related to sustainability. This if they really want that those investments in fact help to improve the competitiveness of the company. The mining industry benefits from natural capital that extracts, so it should implement strategies that lead to remunerate such benefit to the territories (Almaguer, 2007). One option is through the transformation of natural capital in other types of non-existent capital or poorly developed in their areas of influence. In this way, the value generated by the extraction of underground resources is shared and additionally contributing to improving the quality of life of the communities. Historically, mining industry has been into several problems to achieve this, which represents one of the aspects that has most influenced the current reputation of mining industry in some regions of Latin America. Many communities, local governments and civil society organizations continue to associate this activity with the destruction of the social fabric and ecosystems in the territories, and their opposition against companies working in the areas has led to affect the operational continuity of many projects (Hamann, 2003; Prno and Scott, 2012; Slack, 2012)."

Jan 1, 2017