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A viable mineral economy requires availability of economic deposits, the ability to exploit then, and protection of the public interests. The natural tendency for each party to consider only its legitimate self interests can lead to delays or deadlocks. The paper presents several viewpoints aimed at opening each party's mind to the ideas of others in the hope that negotiations might be more reasonable and rapid for the benefit of all concerned.

Jan 1, 1979

By James J. Olson

Most of the projects summarized in this paper are funded under the Bureau's Advancing Metal-Nonmetal Mining Technology program and are part of the in situ mining subprogram coordinated at the Twin Cities Mining Research Center. The borehole mining equipment development, are funded under the Bureau's Advancing Coal Mining Technology program, is essential to accelerated progress in the in situ mining subprogram, and some background information on this concept is included. The initial in situ research projects started in 1971-72 evaluated some of the critical blast design parameters for in situ copper leaching. The present program totals about $1 million per year and includes in-house research projects, cooperative (cost-sharing) projects with the mining industry, and research and development contracts. Two different extraction schemes are under investigation: inplace leaching and borehole (or slurry) mining. The principal commodity targets for the Bureau's improved in situ mining technologies include copper, uranium, coal, and potash. The principal purpose of this paper is to inform the mining industry of the in situ mining research recently completed or being conducted by the Bureau of Mines. In addition the Bureau encourages companies to comment on the program accomplishments as well as offer suggestions on top priority research needs for improving the in situ mining methods described in this paper.

Jan 1, 1977

By Richard A. Levins

The imposition of non-market regulations, such as the proposed SO2 standards for coal combustion, will typically lead to less efficient (thus more costly) production in a free enterprise system. For the coal industry these increased costs will occur in several ways, among which are mining less accessible low sulfur reserves and transporting low sulfur coal to distant markets. There are, of course, social benefits of reducing the S02 emissions from the use of high sulfur coal. The social benefits include decreased health risks, reduced damages to property, and certain unmeasurable benefits associated with the aesthetic appeal of clean air. Proponents of Federal S02 standards argue that the benefits gained from reduced emissions will exceed the costs borne by the coal industry and society in general in meeting the regulations. The purpose of this paper is to investigate the degree to which costs of meeting future energy demands from coal will change under different sulfur standards. No attempt is made to estimate the benefits of imposing regulations. Specifically, the impact of SO2 standards on the private costs of meeting regional coal demands, the competitive positions of the nation's major coal producing regions, the degree to which strip mining as opposed to underground mining will be feasible, the amount of coal being processed, and the amount of coal transported over major rail routes will be analyzed.

Jan 1, 1976

By T. T. Toomver

The evolution of Inco's Selective Reduction Smelting Process as practised today is described, beginning with the initial laboratory experiments on small samples to the processing of large bulk samples through pilot plant equipment. For both the Guatemalan and Indonesian (Soroako) ores, the initial screening tests using hydro-, vapo-, and pyro-metallurgical processes showed that the latter was the most promising both metallurgically and economically. Later, larger scale tests confirmed the earlier testwork.

Jan 1, 1979

"Australia’s largest rail freight network operator, the Australian Rail Track Corporation (ARTC), has selected GE Transportation’s Movement Planner solution as the key technology enabler for its Hunter Valley-focused network control optimization program.ARTC’s Newcastle-based network control, is the nerve center of Hunter Valley rail operations, where locally based train control professionals make thousands of decisions every day to safely support the annual movement of more than 24 kt/h (26,400 stph) of freight, and tens of thousands of coal, freight, grain and passenger trains each year.ARTC plans to transform its train control function by integrating and then building on Movement Planner, an advanced software solution by GE Transportation that provides real-time rail traffic planning and optimization to enable freight to move more efficiently. “The Hunter Valley rail network is one of the busiest and most complex in the country, supporting the largest coal export port in the world,” ARTC managing director and chief executive officer John Fullerton said.“As bulk freight demands grow, rail operators like ARTC and supply chains like the Hunter Valley coal network need to be creative in the way they respond so the Australian economy doesn’t miss out. That’s why we have conducted a worldwide search to find globally proven solutions that will improve our network productivity and efficiency,” Fullerton said.The Movement Planner solution considers multiple factors including train schedules, trafficcontrol systems and train movements relative to each other and then develops an optimized traffic plan for the trains throughout the network. Existing GE customers have benefited from increased visibility of network operations, higher velocity, less dwell times, and improved on-time performance across their networks."

Jan 1, 2018

By MARK J. VANARELLI

Estimating groundwater inflows in rock deep tunnels is critical to the safety of personnel constructing the tunnel and the cost of construction. This paper presents two case studies for estimating steady-state groundwater inflows into deep rock tunnels. The case studies included the Chattahoochee and Nancy Creek tunnels. In this paper, statistical methods were applied to packer test data obtained from exploratory borings during geotechnical site investigations. A semi-empirical procedure was utilized for estimating groundwater inflows into these deep rock tunnels. It is the most widely used method/procedure in the tunnel industry. The Chattahoochee and Nancy Creek tunnels are deep rock tunnels which exhibit radial flow conditions. For the radial flow condition, a statistical analysis presented in this paper indicates that the semi-empirical procedure works well; however, variations in the procedure and/or an insufficient amount of testing could lead to underestimations of the inflow quantities. Packer test data plotted in histograms were observed in all cases to be log-normally distributed for the radial flow condition. Modeling using Monte Carlo simulations was observed to be an effective tool for removing irregularities in the distribution of the data and incorporating high-end permeability data to derive reasonable groundwater inflow estimates. This paper is based on the PhD thesis entitled “Improvements to the Current State of the Practice in Steady-State, Groundwater Inflow Estimates into Rock Tunnels based on the Application of Statistical Analysis Methods of Packer Test Data obtained from Exploratory Borings During Geotechnical Site Investigations.”

Oct 9, 2020

By Will B. Jamison

The most serious safety problems encountered in U. S. underground coal mines today are related to the roof bolting operation. Also, roof bolting is usually the operation which limits coal production of the section. The purpose of my paper is to review some of the research, developments, and new ideas related to roof bolting. Many of these ideas have originated at. coal mines or with manufacturers. Most of the research on fundamental improvements has been funded by, and is a part of, the excellent and broad plans of the Bureau of Mines.

Jan 1, 1977

By L. Zhou, J. P. Rider, T. W. Beck, J. A. Organiscak, Y. Zheng

The National Institute for Occupational Safety and Health’s Office of Mine Safety and Health Research recently developed a series of models using computational fluid dynamics (CFD) to study the gas distribution around a continuous mining machine with various fan-powered flooded bed scrubber discharge configurations. CFD models using Species Transport Model without reactions in FLUENT were constructed to evaluate the redirection of scrubber discharge toward the mining face rather than behind the return curtain. The following scenarios are considered in this study: 100 percent of the discharge redirected back toward the face on the off-curtain side of the continuous miner; 100 percent of the discharge redirected back toward the face, but divided equally to both sides of the machine; and 15 percent of the discharge redirected toward the face on the off-curtain side of the machine, with 85 percent directed into the return. These models were compared against a model with a conventional scrubber discharge, where air is directed away from the face into the return. The CFD models were calibrated and validated based on experimental data and accurately predicted sulfur hexafluoride (SF6) gas levels at four gas monitoring locations. One additional prediction model was simulated to consider a different scrubber discharge angle for the 100 percent redirected, equally divided case. These models identified relatively high gassy areas around the continuous miner, which may not warrant their use in coal mines with medium to high methane liberation rates. This paper describes the methodology used to develop the CFD models, and the validation of the models based on experimental data.

Jan 1, 2015

"A carefully planned laboratory test program is the foundation for the successful development of a sulfide flotation process. In this paper, the development of a copper-molybdenum flotation process is described. However, the concepts discussed can be applied to most sulfide flotation systems and to many industrial minerals projects as well. Each step is examined, beginning with sample procurement and covering sample preparation, flotation test preparation grinding, scoping flotation tests for reagent scheme selection, rougher flotation parameter evaluation and cleaner circuit evaluation, through to locked-cycle testing and pilot plant design and operation. Ore variability and modeling to determine the response of various ore types to the optimum conditions established is also examined.IntroductionA carefully planned laboratory test program is essential for the successful development of any sulfide flotation process. These programs usually begin with a series of batch tests on several ore type composites to evaluate appropriate reagent schemes and delineate optimum rougher flotation conditions, such as primary grind size, flotation pulp density, flotation pulp pH and retention time. Cleaner parameters such as regrind size requirements, cleaner pH, pulp density and number of stages are then defined. Semicontinuous locked-cycle tests are performed using the parameters established in the batch tests to determine the effect of middling streams recirculation on flotation performance. The data generated and the experience gained in the locked-cycle tests may be used to design and operate a continuous pilot plant if relatively large amounts of concentrate are required for further process development, such as optimization of byproduct molybdenum production from bulk copper-molybdenum concentrate.A comprehensive ore variability program is undertaken to determine the response of various ore types to the optimum conditions established. These ore variability programs often test hundreds of samples in standardized batch rougher and cleaner tests to ensure that the orebody is well understood.This article describes the development of a copper-molybdenum flotation process, but the concepts discussed can be applied to most sulfide flotation systems and many industrial minerals projects. The block flow diagram in Fig. 1 provides an overview of the development process."

Jan 1, 2016

By W. G. Pariseau

A study of coal pillar strength at the Beehive Mine in central Utah was done in the 1970s. This study was a cooperative effort by the University of Utah, RE/SPEC, Inc., and the American Coal Company and was funded by the U.S. Bureau of Mines. Mine measurements of closure at 117 points and pillar stress using 119 vibrating wire stress gauges were made during retreat mining in this room-and-pillar operation. Laboratory testing for the strength and modulus of 372 coal cylinders up 0.3 m (1 ft) in diameter and 0.6 m (2 ft) in length was also done. Two-dimensional finite element model analyses complemented the study. However, the real world of mining is three-dimensional and in consideration of the significant advances in computing power since the time of the original study, a revisit of the data seemed warranted. In this regard, a novel finite element method was used that allows for the whole-mine analysis of tabular excavations on the kilometer scale and yet enables details to be obtained at pillar walls on the meter scale. The effects of material properties variability in situ and of joints can also be taken into account. Results that compare computed two- and three-dimensional seam-level closures with mine measurements show noticeable differences; three-dimensional results are reasonable, while two-dimensional results overestimate closure by nearly a factor of two.

Jan 1, 2014

By Yanan Zhang, Hongwei Deng, Feng Gao, Bo Ke

Recently, liquid carbon dioxide (L-CO2) blasting technology has attracted attention due to its good fracturing effect and safety performance, especially in coal seam permeability improvement. This paper analyzes the blasting effect of L-CO2 based on experiments and studies the fracturing mechanism from the perspective of stress wave action via theoretical analysis and peridynamic simulations. The results indicate that L-CO2 blasting achieves a good fracturing effect without forming a crush zone, and the loading rate and strength of the stress wave are key factors.

Jan 19, 2022

By Paul Gilmour

"The principal role of the geologist is to recognize the existence of phenomena before trying to explain them" - B.M. Keilau, 1825; A. Holmes, 1965 Some important groups of mineral deposits in the layered rocks of orogenic belts or greenstone belts occur in horizons characterized by the presence of exceptional amounts of silica, iron and carbon, with more or less significant amounts of manganese. Generally, the rocks involved are well banded. In practice, these five physical features - four compositional and one geometric - are found with many lithological guises. Iron formation, in the full, modern sense of the term (James, 1954), quartzite, ferruginous quartzite, chert, jasper, "tetsusekiei" (Horikoshi, 1969), tuffaceous jasper ("purple porphyry" - Anderson and Creasey, 1958, p. 36), ferruginous or graphitic shale, argillite, slate or schist, and hematitic tuff are but a few of the more familiar of the names that have been assigned to these rocks. Widely acknowledged and well-documented examples of metallic deposits found in such sediments include concentrations of iron and manganese and stratabound, polymetallic, massive pyritic sulfides. Less familiar examples include occurrences of asbestos (Miles, 1953; and Coetzee, et al., 1976), antimony (Coetzee, 1976), and perhaps stratabound deposits of Au-Cu-U-W-etc., such as Aitik in Sweden (Mining Magazine, 1975; and Nilsson, 1979) and Olympic Dam in South Australia (Roberts and Hudson, 1983). The case of gold is intriguing. An association between gold and iron formation has been identified at several famous deposits and districts, such as Yellowknife, N.W.T. (Morton, 1979), Homestake, S. Dak. (Sawkins and Rye, 1974), Vubachikwe, Zimbabwe (Fripp, 1976) and the Barberton district, R.S.A. (Hammerbeck, 1976). Yet a critical reading reveals the existence of many other hitherto unsuspected examples. The purpose of this note is to draw attention to that omission and the apparent explanation for it. It is not hard to detect the two most probable reasons for the discrepancy between reality and the record.Most occurrences of gold are associated, not with the familiar banded iron formation or interbedded magnetite and chert (technically, the magnetite-banded variety of the oxide facies), but with the enigmatic carbonate, sulfide and silicate facies of iron formation and/or with rocks evidently related to iron formation. All too commonly, the unfamiliar facies of iron formation have been identified by field and mine geologists and not a few researchers as products of regional metamorphism and hydrothermal alteration, as mafic igneous rocks, or as conventional sediments, ie., without regard to their intrinsically ferruginous nature. The justification for these two complementary assertions is largely to be found in the recognition of a characteristic suite of metals and minerals in gold deposits known to be associated with iron formations. Although, from a geological standpoint, a lithological association is more important than a mineralogical assemblage, the latter is the more likely of the two to be diagnostic. This arises from the different natures of mineral and rock classifications, The identification of a mineral or an element is a matter of fact. Owing to the genetic component inseparable from petrographic nomenclature, viz., "igneous": a rock (believed to have been) derived from a melt, the identification of rocks depends on inferences or conclusions about their mode of formation - conclusions that are commonly debatable and, all too often, involve subjective judgements. This is especially prone to be true, if - as at many of the gold occurrences in question - the host rocks have been metamorphosed and/or "altered". In the notes that follow greater weight has accordingly been assigned to elemental and mineralogical than to host rock composition. In other words, if, in a given gold occurrence, the suite of metals and minerals present conforms to the standards of the subject class, whereas the names assigned to host rocks do not, the latter will be viewed as suspect.

Jan 1, 1985

Energy Developments Ltd. (EDL) has developed power plants at two Australian coal mines that featuring 94 gas-fueled Caterpillar G3516 engine/generator sets. They will convert to electricity 145 kt/a (160,000 stpy) of coal-seam methane gas for sale to a local utility. The $100-million project will cut the sites' methane emissions in half, provide a low-cost energy source and offset mine operating costs. The project began in May 1995. It is located at the Appin and Tower longwall underground mines, 80 km (50 miles) south of Sydney in New South Wales. The installation is one of the first to capture coal-seam gas from mine ventilation air and gas drainage systems. Coal- seam gas contains 40% to 60% methane, which fluctuates constantly. The system is expected to convert 578,000 m3/d (20.4 million cu ft/d) of coal-seam gas to 94 MW. It will also reduce greenhouse gas emissions by 3.5 Mt/a (3.8 million stpy) of CO, equivalent emissions. The Appin and Tower mines each produce 2 Mtla (2.2 million stpy) of clean coking coal. They operate around the clock with about 400 workers per site. The mines are owned by BHP Steel, Collieries Division, which will share the revenues from energy sales. The Appin Power Partnership consists of EDL and Lend Lease Development Corp.

Jan 1, 1997

By C. K. Arthur, N. K. Dumakor-Dupey, B. A. Kansake, F. A. Kaba

Autonomous mining systems have been deployed for improving mine performance. However, there is a fear of job losses. Adoption of autonomous systems is envisaged to be resisted by major stakeholders in Ghana due to high illiteracy and unemployment. This paper assesses the preparedness of Ghanaian mining stakeholders for the adoption of autonomous systems to Ghana’s surface mining industry. Closed and open-ended questionnaires were administered to mine stakeholders. Respondents generally expressed unwillingness to accept autonomous systems into Ghanaian mines due to fear of increased unemployment. We propose setting up a mining education fund (MEF) for training stakeholders in autonomous mining systems. INTRODUCTION Mining contributes enormously to the sustenance and growth of global and national economies through the provision of raw materials, employment, revenues and foreign exchange (Carvalho, 2017; ICMM, 2017; Cordes et al., 2016; Solomon et al., 2008; Walser, 2000). The International Council on Mining & Metals (ICMM, 2014) reported that globally, formal mining employs approximately 2.5 million people. Many resource-rich countries, especially the developing ones, have experienced strong socioeconomic growth propelled by the discovery and extraction of valuable minerals. McMahon and Moreira (2014) reported a positive linkage between mining and sustainable development. They revealed that averagely, resource-rich countries have improved Human Development Index (HDI) scores than countries without mineral resources. Mining remains a crucial industry in Ghana’s economic development (Bermúdez-Lugo, 2016; Amponsah-Tawiah and Dartey-Baah, 2011). Over the years, mining has contributed significantly to the gross domestic product (GDP) of Ghana. In 2013, mining accounted for 1.7% of Ghana’s GDP and about 19% of government revenues (Ghana Chamber of Mines, 2015). The Ghana Chamber of Mines also reported that mining contributed over 50% of foreign direct investment, 37% of export earnings and 1.1% of direct employment revenues. The US Department of Energy (DOE) estimates that 65% of coal, 92% of metals and 96% of industrial minerals are mined using surface mining methods (DOE, 2007). Generally, mining is a capital-intensive venture, with high operating cost, hence there is a constant demand for mining companies to seek efficient cost reduction and production maximization strategies. One strategy being pursued keenly is automation, which is noted to improve productivity, and worker safety at minimal cost. According to Parreira (2013), mining automation involves direct teleoperation whereby workers remotely control the mining process using computers from a control room.

Jan 1, 2019

By L. J. Hoover

The objective of this study was to assess the health and environmental impacts of fluidized-bed combustion (FBC) of coal, specifically as applied to baseload generation of electrical energy by utilities. The study* was a short-term effort that based its analyses on information derived from the experience of the group or quickly obtained from the literature. The approach was to compare Atmospheric Fluidized-Bed Combustion (AFBC) and Pressurized Fluidized-Bed Combustion (PFBC) with two current technologies: low-sulfur coal combustion (LSC) and flue gas desulfurization (FGD) used with high-sulfur coals. A wet-limestone process was selected as the FGD technology. The impacts compared involved not only health and environment but also sociology, resource use, and dollar cost. Conditions for comparison were centered around a nominal date of 1988, when initial operation of commercial AFBC plants may occur. The PFBC has a later introductory date, a nominal 1995 (its impacts relative to other competitive technologies now in the R&D stages were not compared.)

Jan 1, 1978

By A. Noble

"Linear circuit analysis (LCA) is a fundamental tool that may be used to evaluate, design and improve the performance of mineral separation. The traditional LCA methodology provides a comparative evaluation of circuit designs purely from the unit interconnections. The quantitative approach uses the analytical circuit solution to evaluate the slope of the circuit’s partition curve at the midpoint. Since the partition slope is often associated with a separation’s general selectivity, this numeric value is used to compare and rank alternative configurations. Unfortunately, the partition curve slope only reflects the separation potential of middling material. By itself, this value does not account for the relatively high unit dollar value of pure material or the gains and losses in mass yield associated with alternative circuit configurations. Realizing the value in the LCA methodology, but respecting the limitations of the partition slope valuation, the authors have derived two new performance indicators that quantitatively address pure particle misplacement (the Partition Moment of Inertia) and circuit mass yield (the Yield Score). Together, these parameters provide a better indication of separation economics in typical mineral and coal separation systems. Since the two parameters provide independent information on circuit selectivity and circuit yield, a Pareto efficiency, multi-objective function selection approach is proposed for preliminary circuit selection.IntroductionOver the past 30 years, numerous scientific and industrial studies have proposed various mineral processing circuit design methodologies that attempt to optimize the allocation of separation resources within the processing plant. Over this period, the methodologies have undergone various transitions, including the increased inclusion of process models and computationally intensive algorithms, as well as a general shift from a purely technical solution (Lauder and McKee, 1986) to partially economic solutions (Abu-Ali and Sabour, 2003; Cisternas et al., 2014). Today, circuit design is largely driven by flowsheet simulation; however, no consistent design methodology is used across the industry.One intriguing approach for circuit evaluation is linear circuit analysis (Meloy, 1983a). This method evaluates the separation potential of the circuit solely considering the unit configuration and stream interconnections. No preliminary data other than the basic circuit configuration is required to use the approach."

Jan 1, 2015

Bigger is indeed better in today's surface mining operations. That is especially true regarding haul trucks. Building larger, "supersize" trucks, however, means designing more powerful engines and drive systems that are also more efficient and environmentally friendly. And miners are demanding that these trucks have longer service lives with minimum maintenance. So truck makers are teaming with engine manufacturers and mining customers to design these larger trucks that will ultimately lead to reduced mining costs. About 180 of those truck makers, engine designers and miners gathered in Tucson, AZ in September to discuss the state of haul trucks in today's mining environment. Haulage 2000 was sponsored by World Mining Equipment and attracted attendees from around the world. Manufacturers described the latest in haul truck advancements. These included the design of more powerful engines, improvements to mechanical and ac and dc drive systems and suggestions on how to reduce maintenance spending. Technology improvements in tires for larger struck was discussed as was the cost efficiency of new, lighter-weight bed liners. The following is a summary of a handful of the presentations.

Jan 1, 1997

By Ditend Tesh, Mallikarjun Pillalamarry, Nikowa Namate, Harmony K. Musiyarira

Many reports have been written about the issues surrounding small scale miners’ challenges in Namibia; yet little has been done to address these challenges. There has been a fragmented approach to address these challenges. Various government arms and donor organizations have utilized piece meal methods in the past in trying to make improvements on the productivities across the sector, but with no meaningful success. This has led to the design and implementation of inappropriate technologies and support services for the sector. The structures of many of the semi-precious stones mining businesses are informal, with very little royalties received by the government. Miners often work informally or illegally and they fear government interference and they distrust outsiders, resulting in them withholding production information. The presence of small scale miners is quite often associated with major challenges, including poor safety and environmental management standards, the spread of communicable diseases and poor working conditions. The majority of the miners employ uncontrolled extraction techniques which damage the crystals and mineral specimens, resulting in intermediate and final products of low quality along with high wastage at the extraction stage. The vision of the Namibian government is to expand the range and value of semi-precious stones and jewelry products processed within Namibia, while curbing illicit flows of raw stones. This will simultaneously secure maximum benefit for the country. This study investigated the interventions aimed at making the small scale mining sector in Namibia sustainable. A baseline study was conducted to analyze the current situation and characterize the industry, including a SWOT analysis. Information was collected through questionnaires, interviews, consultative meetings, field visits and workshops in order to profile the sector. The baseline study results were used in developing interventions for improving artisanal and small scale mining operations. The main challenges for the Namibian semi-precious sector were identified as: factual information about raw material resources and its beneficiation are insufficient or not available, lack of skills, lack of education and access to finances, rudimentary exploration and mining practices, trading and logistics that are not functioning effectively and inadequate sector governance. One key finding of this study was that Namibia is not benefiting through value addition due partly to illicit flows of the uncut stones and to the fact that lapidary is not much pronounced to a greater extent. The following strategic interventions were identified as key in ensuring the sustainability of the small mining sector in Namibia: conducting geological assessment to identify new deposits and quantify the existing ones, improving exploration and mining practices, investing in education and training, creating an enabling environment and improving the sector governance and strengthening the sector organization and supporting the infrastructure.

Jan 1, 2017

By J. R. Muhm

Environmental due diligence investigations, also known as Phase I Environmental Audits, are increasingly important to major investors, venture partners, or prospective purchasers or sellers of mineral properties. Knowledge of environmental risks associated with a property will allow better appraisal of a property's overall desirability prior to completing the transaction. It is possible that the cost of environmental cleanup could exceed the value of the property. Topics appropriately investigated include permit status, water quality, past use of the property, hazardous materials management, storage tanks, public records pertaining to the environmental character of the property, and environmental costs.

Jan 1, 1991

By Cary Hirner, Dan Lopez, Ross Webb, Stephen O’Connell

"Construction of the largest desalinization plant in the Americas has commenced in northern Chile. It is part of a several billion dollar expansion at a copper mine whose operations nearly stopped due to the challenge of securing a reliable source of water from the Pacific Ocean in a safe and environmentally sound manner. This paper discusses the risk management, design and construction of a quadruple chamber intake and outfall shaft, high capacity pump station, three 7m diameter vertically drilled marine shafts and three subsea tunnels constructed through challenging Andean hard-rock geology. The three 2.5m diameter subsea microtunnels are being mined with vertical curves through variable quality rock 30 meters beneath the ocean and retrieved in the wet from the 7m diameter marine shafts. INTRODUCTION AND BACKGROUND The battle for securing the rights to a constant water supply is a worldwide issue and nowhere is that more evident than the Atacama Desert of Chile, the world’s driest place with areas of the desert that have not seen rainfall in recorded history. The Atacama Desert also happens to be home to some of the world’s largest ore deposits which require huge amounts of water to extract and process. What available water there is comes from three main sources: deep seated wells, glacial water from the Andes Mountains, and desalinated water. Vying for water from wells and glacial streams and lakes are numerous agricultural and domestic facilities in the valleys surrounding the Atacama Desert. Environmental regulations and legal rulings have limited the amount of “natural” source water which can be used for mining purposes. Desalination plants are a known solution for combating water scarcity, albeit a costly one. The total estimated cost of constructing this desalination plant is over $3B USD, which will include a 2500lps capacity and an approximately 118km pipeline from the coast up to the mine located in the Andes. The overall scope of the project includes design, procurement, and construction packages for the 2500lps desalination plant including the seawater reverse osmosis plant, water conveyance to the mine, power transmission, the reservoir and the marine works package which forms the basis of this paper. Key components of the underground construction portion of the Marine Works are:"

Jan 1, 2016