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By William R. Yernberg

The combined 78th Annual Minnesota Section of SME Meeting and 66th Annual University of Minnesota Mining Symposium was held April 19 and 20, 2005, in Duluth, MN. More than 300 mining professionals, including engineers, executives, mining managers and suppliers, from throughout the United States and eastern Canada attended the meeting. This year’s theme was “Global Demand: A Window of Opportunity.” The meeting included a keynote address, technical presentations and a trade show. The atmosphere at this year’s meeting was upbeat. The iron ore mining industry in Minnesota is experiencing one of its biggest turnarounds in history. Because of greater demand, iron ore prices increased 20 percent during 2004 and 71.5 percent so far in 2005.

Jan 1, 2005

Peru has become an established mining country. The industry and industry-related businesses account for a significant amount of the country´s revenue, on state and local levels. But like other countries with thriving mining industries, Peru has seen its mining industry revenues fall off in recent years due to a lackluster global economy. And the mining industry in Peru must also deal with increasing concerns about mining?s environmental impacts, local community and other social issues, as well as a regulatory environment that has placed more restrictions on what miners can do. That said, the Peruvian government is beginning to realize how important mining and natural resource development is to building the nation?s economy, improving its infrastructure and lifting its population out of poverty. The government support was evident during the Perumin 2013 mining convention, held in September in Arequipa. In addition to Peru?s President Ollanta Humala speaking at the closing ceremony, the country?s ministers of Energy and Mines, and Economy and Finance participated in the event, as well as numerous other federal and state authorities. Perumin is put on by the Instituto de Ingenieros de Minas del Peru (IIMP, or Peruvian Institute of Mine Engineers). The 31st edition of the convention, billed as the ?world?s largest mining convention? by the IIMP, this event was led by Abraham Chahuan CEO of Antamina and Romulo Mucho (SME member) as president of IIMP, attracted about 118,000 participants from more than 48 countries. This was more than the anticipated 75,000 attendance and well past the 51,000 people who attended the 2011 convention. The last edition of PERUMIN was led by the CEO of Compañía Minera Antamina, Abraham Chahuan and Rómulo Mucho (SME member) and representative of the IIMP. The event attracted more than 1,000 journalists from all over the world, the IIMP said. A total of 2,213 booths from equipment and machinery supplying companies from the five continents were present at the Mining Technology Exhibition (Extemin), including companies from the United States, Canada, China, South Africa, Germany, Australia, Brazil and Chile, among others. The convention has grown so large in recent years, that the IIMP shifted its location from Tecsup vocational school in Arequipa to the Cerro Juli Convention Center. The venue is 116 percent larger than Tecsup, the IIMP reported, covering about 20 ha (40 acres). It was reported by Latinomineria magazine that about 10 million Peruvian soles were invested in the new venue to create a world-class events center. It was also estimated that the event generated more than 234 million soles to Arequipa?s economy.

Feb 1, 2014

By Terry W. Engelhart

"A computer-based approach to online supervisory control and operations management of bulk materials handling terminals". This paper describes an integrated computer facility supporting the functions and responsibilities of shift operations, scheduling, maintenance and management using real-time interactive techniques. The functions and responsibilities as related to coal export terminals are specifically addressed, although these functions would be equally applicable to other terminal configurations and other commodities. A discussion of the resulting benefits are presented: - throughput efficiency - long-term planning and scheduling, using simulation - operations monitoring and protection - demurrage/despatch optimization - preventative maintenance - operational productivity

Jan 1, 1982

By P. Guliov

In the first part of this paper the authors present an overview of industrial minerals produced in the Canadian provinces of British Columbia, Alberta and Saskatchewan, and supplied to the Pacific Rim countries. The second part outlines some of the unique opportunities for industrial minerals that exist in the three western Canadian provinces and those minerals we feel have development potential for overseas markets. Because of time constraints, it is not an exhaustive presentation on industrial minerals, but is focused on a few selected minerals that we believe have high potential.

Jan 1, 1990

By H. Lowers, B. Van Gosen

The Iron Hill (Powderhorn) carbonatite complex is a 31 km2 alkalic intrusion located about 35 km south-southwest of Gunnison, Colorado. The intrusion has been well studied and described because of its classic petrology and architecture of a carbonatite-alkalic complex. The complex is also noteworthy because it contains enrichments of titanium, rare earth elements, thorium, niobium (columbium), vanadium, and deposits of vermiculite and nepheline syenite. In particular, the complex is thought to host the largest titanium and niobium resources in the United States, although neither has been developed. It may be economic to extract multiple resources from this complex with a well coordinated mine and mill plan.

Jan 1, 2007

By Z. Henderson, J. Saylor, L. R. Mendoza

"Diesel particulate Matter (DPM) is a byproduct of fuel combustion in diesel engines. It is classified as a carcinogen, with associated respiratory and cardiovascular health effects. The composition, size, and concentration of DPM is dependent on factors such as engine type, loading and fuel composition. Though a number of DPM abatement and control strategies currently exist, particularly in underground mining environments, occupational exposures remain a serious health concern. As a novel abatement approach, DPM scavenging by fine water or “fog” droplets has been proposed and a laboratory set-up has been built to test the efficacy on engine exhaust. Here, we describe a series of tests that varied engine load, system flow rate and fog drop number density. While none of these factors had overwhelming effects on the results within the ranges tested, the improvement in DPM mass removal attributed to the fog treatment was about 45% on average in comparison to no treatment. INTRODUCTION Diesel engines have seen widespread use for well over a century due to their relatively high thermal efficiency and fuel economy1. More recently, however, adverse health risks of diesel exhaust have become increasingly clear. Many of these risks are associated with the physical and chemical properties of exhaust components1–3. The term diesel particulate matter (DPM) is used to refer to the solid components of diesel exhaust, which are a mixture of elemental and organic carbon (EC and OC) and minor constituents including sulfates and metal ash3. The OC fraction of DPM results from unburned fuel and lube oil, whereas EC or soot is formed during the combustion of locally rich regions within the fuel. DPM is classified as a carcinogen6,7 and epidemiological studies have demonstrated a positive correlation between long-term exposure to DPM and other combustion-related fine particulate and increased cardiovascular and pulmonary diseases8,9. Diesel engines operate in relative fuel rich/oxygen lean conditions and are characterized by relatively high emissions of particulate as compared to spark-ignition engines2,3,10. Typically, these emissions range from 107 – 109 particles/cc and cover two primary size ranges: the nuclei mode where particles have diameters less than about <50 nm, and the accumulation mode where diameters are from about 50-10,000 nm. Most OC resides in the nuclei mode as semi-volatile compounds, while most EC is in the accumulation mode3. The physical and chemical properties of DPM vary with the type of engine, fuel (e.g., petro- vs. bio-diesel) and operating conditions such as loading (i.e., a function of torque and rotational speed)2,3,9,11,12. Loading is a particularly important factor with respect to DPM toxicity9,13,14, and on the effectiveness of after-treatment technologies2,3,15. Engine load alone can affect the EC/OC ratio, and the size distribution and number density of DPM. For diesel engines, the load is roughly proportional to the equivalence ratio3, defined as the actual fuel/air ratio over the stoichiometric fuel/air ratio for complete combustion. Light loads generally favor the formation of OC and small particles. As load is increased the volatiles are oxidized leading to larger soot particles (i.e., EC), but lower total number density of DPM. With further loading, the formation of soot offsets the decrease in volatiles, resulting in increased DPM mean size and number density3."

Jan 1, 2017

By Anna Kate Miller, James J. Brady, Hamza Jaffal, Ritika Sangroya, Chadi El Mohtar, Wing Shun Kwan

"The design of an appropriate pre-grouting program can be the difference between a successful tunnel construction and an expensive on-the-go repair. However, current grout design relies heavily on rulesof- thumb and outdated charts. The geotechnical investigation is rarely targeted towards grouting design and the final grouting decisions are made based on fines content or soil classification. The current paper presents an experimental study performed to determine the optimal grout for a tunnel in soft ground below the ground water table (GWT). The testing program consisted of sieve analysis and undrained static triaxial tests on reconstituted sonic samples. Rheological tests were used to compare the different grout mixes and identify best candidates before performing one-dimensional permeation tests. Pressure and volume measurements during the permeation tests, along with the unconfined compression strength results on the permeated soils, helped evaluate the filtration potential for the different grouts and select the optimal grout.INTRODUCTIONConstruction of the Millwoods Double Barrel Replacement Project commenced in 2009 and was expected to be completed by 2015. To facilitate ongoing city development in south Edmonton, the City implemented construction of a major sanitary trunk network along 91st Street and 30th Avenue. The project involved the design and construction of approximately 1.2 miles (2 km) of 7.8-ft (2,400 mm) sanitary tunnel and 2.1 miles (3.4 km) of 11.5-ft. (3,500 mm) and 9.5-ft. (2,900 mm) storm tunnel. Part of the project also involved the conversion of the existing double barrel storm and sanitary trunk to full sanitary service, and reconnecting the local storm sewers from the double barrel pipe to the new storm tunnel. The tunnels range in depth from 26-ft. (8 m) to 115-ft. (35 m) and are being installed using a one pass system with precast concrete segmental liners."

Jan 1, 2016

By H. R. Butler, J. F. Church, A. T. MacGibbon

Introduction Inco is the major North American nickel producer. Initially based in Sudbury, Ontario, its past exploration activity was directed toward finding new nickel deposits. New nickel sulfide discoveries outside Sudbury have included Thompson, Manitoba; Shebandowan, Ontario; and Widgiemooltha in Western Australia as well as a host of nickel laterite deposits. The company is currently diversifying into other commodities, including gold. Inco&apos;s exploration department participated in uranium discoveries in Saskatchewan and chromite discoveries at Tiebaghi in New Caledonia. In addition, it found new gold deposits at Lupin, Northwest Territories; Crixas, Brazil; Hoyle Township, Ontario; and Casa Berardi in Quebec. Crixas and Casa Berardi are currently being evaluated by underground exploration. Figure 1 shows some Canadian Shield gold locations where Inco is or was an active participant. Base metal developments Base metal exploration in shield areas has been greatly eased by applying scientific studies. Archean nickel sulfide deposits have been found using komatiitic-flow models (Fardon, 1971). Volcanogenic massive sulfide model has been applied to copper-zinc deposits (Sangster and Scott, 1976). Such deposits were subsequently seen developing on the sea floor through black smokers (Spiess, MacDonald, and Atwater, 1980). Sedimentary processes were recognized early as important in ore formation, particularly in the southern hemisphere (King, 1976). And many ore deposits are now regarded as a simple part of the geological column (Stanton, 1960 and 1972). Petrographic work on alteration patterns in and around ore bodies was used to develop standard porphyry copper models (Lowell and Guilbert, 1970). Epithermal models for precious metals followed. Stratigraphic zonation patterns have been formulated for base metal deposits, including keel facies, ore facies, and cap or distal facies. Gold developments The work on base metal deposits naturally spilled over into precious metal exploration when the gold price was allowed to float on world money markets. Early work on elements associated with gold deposits, especially arsenic, tellurium, selenium, and mercury, pioneered more detailed geochemical work (Bagby and Berger, 1985; and Groves, Ho, and Houstoun, 1984). Geochemical patterns have been recognized around microfine gold deposits. And the study of gold precipitation patterns in modern geothermal systems has helped understand gold deposition. In the late 1960s and early 1970s, it was noticed that numerous Archean banded iron formations contained anomalous gold values. From this and other observations, the syngenetic exhalite gold model has developed. Gold deposits also occur along shears in some plutons such as the Belmoral mine in Quebec. This indicates the importance of epigenetic processes in ore formation. Shield ore settings Initial studies recognized that the major gold camps in the Canadian Shield were mostly in greenstone belts and found along "breaks," especially zones of faulting and sedimentation. Gill (1948) wrote, "Only recently, as a result of detailed mapping, has the importance of major schist zones such as the Larder Lake, Cadillac, Porcupine Creek, and Destor Breaks been recognized. These zones of persistent adjustment mark broad belts favorable for ore occurrence." The importance of shearing in ore location and regional greenstone stratigraphic position close to late sedimentary packages was clearly understood. And structural models have been further developed for some Canadian ore deposits (Hubert, Trudel, and Gelinas, 1984). In the Beardmore-Geraldton camp of northwest Ontario, the importance was soon recognized of fold noses in banded iron formation, as localizers for gold ore. This importance had also been recognized in Western Australia,

Jan 2, 1987

By A. Newman, A. Brickey

Although some of the prevalence of openpit production scheduling software can be explained by the predominance of openpit mining throughout the world, other factors have led to a lag in corresponding underground software. We explain mathematically why underground production scheduling is more difficult than its openpit counterpart and provide directions for research in the underground scheduling arena.

Jan 1, 2014

By Ray Brainard

The Jollyville Transmission Main will be a 10.5-km- (6.5-mile)-long, 213-cm (84-in.) diameter rock tunnel. The tunnel will pass beneath the Balcones Canyonlands Preserve, which was established to protect two endangered bird species, six endangered cave invertebrates and a threatened salamander. To address the sensitive habitat that the transmission main is to pass through, the city of Austin developed an environmental commissioning (EC) process that brought together environmental engineers and scientists, the city?s project management team and the designer team to work collaboratively to meet the city?s goals of producing a cost-effective design while also protecting the environment. This paper describes the environmental commissioning process and the benefits it brought to the project and environment through some unique environmental mitigation measures to protect this sensitive area.

Jan 1, 2012

By Wilbur J. Morin

Construction of Flaming Gorge Dam in northeastern Utah necessitated the construction of a new state highway, Utah-260, to provide access to the dam and the town of Dutch John. A 550-foot arch structure was designed to span Cart Creek, about one mile southwest of the dam. The rock exposed at the site is highly fractured quartzitic sandstone with interbedded shale of the Precambrian Uinta Mountain Group. Eight exploratory holes were drilled, four in each abutment area, to determine rock types, the extent of fracturing at depth and rock strength. Drill cores in the west abutment revealed blocks of quartzitic sandstone loosened by the weathering and partial removal of underlying shale beds. The rock in the east abutment area was found to be highly fractured to depths of 70 feet and as far east as 50 feet from the footing locations. Selected core sections were tested for unconfined compressive strength but the values were not considered-representative of the in-situ fractured rock. To prevent movement along or, perpendicular to open fractures, four drilled-in columns were provided at the base of each footing. These extended 50, feet beyond the base of the footing, along the bearing and inclination of the thrust reaction.

Jan 1, 1963

By J. E. Kogel

Industrial minerals play a central and dual role in the sustainable development (SD) of natural resources. Over the past decade the mining industry has increasingly focused on sustainably extracting and processing industrial minerals. This trend has been driven by higher energy costs, diminishing water resources and sensitivity towards environmental stewardship. Industrial minerals have been used throughout human history as low cost, naturally occurring, materials. Today they are critical components of recycled packaging, energy efficient building materials, light weight paper coatings, and other products critical to the responsible utilization of global resources. As industrial minerals become more widely used in ?green? products, mining companies have established best practices for the sustainable management of industrial minerals mining and processing. These management practices include reducing energy consumption, minimizing water usage, increasing waste recovery through recycling and process optimization, and maximizing the amount of ore extracted per acre of disturbed land. With the commitment to SD principles, quantitative methods for objectively measuring SD performance have become increasingly important. Measuring sustainability impact is a valuable tool for effectively applying SD principles and for making choices that balance sustainable development against other business objectives. SUSTAINABLE DEVELOPMENT AND MINING Sustainable development is a term that has become a common part of our lexicon; however, it has multiple meanings and interpretations leading to a sometimes confusing and contradictory array of definitions. The absence of a single, precise definition reflects the fact that SD is a broad concept or paradigm that offers guiding principles as opposed to a specific set of criteria or regulations enforceable by government or other oversight agencies. While a principle based conceptual approach allows businesses to broadly apply SD practices that are tailored to their specific situation, it has also led the public to sometimes view voluntary corporate SD programs with a degree of skepticism (Walker and Howard 2002). This is particularly true in the mining industry. One reason for this skepticism is that the relationship between SD and mining is misunderstood and to many, sustainably developing non-renewable mineral resources is a contradiction (Rajaram et al. 2005). However, this view takes a very narrow interpretation of the tenets of SD. The second is that mining carries a legacy of poor environmental stewardship that does not accurately reflect current corporate environmental practices Many minerals companies have adopted the Brundtland Comission?s definition of SD (United Nations 1987): ?? development that meets the needs of the present without compromising the ability of future generations to meet their own needs?. This definition is very broad and can be interpreted in a number of ways. It provides a general context for sustainable development and is not intended to provide detailed guidelines addressing specific aspects of sustainable development. To fill this gap the following SD principles were drafted by the international minerals community in 2003 (ICMM 2003): 1. Implement and maintain ethical business practices and sound systems of corporate governance. 2. Integrate sustainable development considerations within the corporate decision-making process. 3. Uphold fundamental human rights and respect cultures, customs and values in dealings with employees and others who are affected by our activities. 4. Implement risk management strategies based on valid data and sound science. 5. Seek continual improvement of our health and safety performance. 6. Seek continual improvement of our environmental performance. 7. Contribute to conservation of biodiversity and integrated approaches to land use planning. 8. Facilitate and encourage responsible product design, use, re-use, recycling and disposal of our products. 9. Contribute to the social, economic and institutional development of the communities in which we operate. 10. Implement effective and transparent engagement, communication and independently verified reporting arrangements with our stakeholders. These guidelines insure that SD concepts are applied equally across the industry while setting a clear performance standard and benchmark against which to evaluate success. By adopting these principles and issuing the Milos Statement (http://www.sdimi.org/milos_decl_October%206_2003.pdf), which provides a more detailed vision for integrating SD into everyday business operations, the minerals industry has embraced SD as a core corporate value. The unifying and holistic approach embodied in SD principles impacts the entire mine to market life cycle and addresses the economic, environmental and social consequences of mining. INDUSTRIAL MINERALS The world economy relies heavily on minerals; they are essential to economic prosperity and the quality of life. Industrial minerals are non-metallic, non-fuel minerals that provide the raw materials for a vast range of products used in most every aspect of daily life. They are mined and processed worldwide and they span the spectrum from relatively low value, high volume commodities (e.g. common clay, crushed stone) that are usually mined locally to high value, low volume specialty materials that are sourced from unique one of a kind deposits (e.g. barite, talc, mica). High volume commodity mining operations are often located near the end use market which, in most cases, means areas of high population density where construction and other urban activities drive demand. In these situations the strict adherence to SD principles is particularly critical as these are highly visible operations that must meet the public?s demand for good corporate citizenship. These operations are similar to chemical or other manufacturing facilities that operate near population centers. In contrast, some mining operations are located in remote but environmentally sensitive regions of the globe where the pressure to mine sustainably is driven by the need to preserve habitats and other

Jan 1, 2009

By Bruce Watzman

Can the United States mining industry achieve its long-stated goal of zero fatalities ? and what will it take to do so? Does it require new laws and regulations, as some propose, and a continuation of the commandand- control model that has been born out of more than 40 years of regulation and enforcement under the Federal Mine Safety and Health Act of 1969? Or, is it time to consider a new model to manage safety and health and drive continuous, sustained improvement? These are questions that many are debating as mine safety performance, while improved, appears mired in a trough where improvement followed by declines seems to have become the rule rather than the exception. Without doubt, U.S. mines have made significant progress in safety performance during the last four decades, yet the stalled decline in fatality numbers, the industry?s report card of its success or failure, has led some to question whether the industry will achieve zero fatalities in U.S. mining by relying solely on the Mine Act?s framework and implementing its regulations. These are questions the CEO-led task force, set up by the National Mining Association (NMA), considered as it sought to identify impediments to zero fatalities posed by the current regulatory regime. Out of that effort came CORESafety, a common safety and health framework that relies on a management system approach to improve safety and health performance. The goal of CORESafety is to achieve zero fatalities and a 50-percent reduction in the rate of injuries in U.S. mining within five years ? 0:50:5. CORESafety is built on the plan-do-checkact model, which has been successfully deployed by industries, mining and nonmining alike, to drive continuous improvement in safety and health performance. The improvements in safety performance that can be achieved by shifting from a command-and-control regulatory approach to a risk-based systems approach built on the plando- check-act model have been documented in numerous industries. For example, the United Kingdom quarrying industry (Fig. 1), not satisfied with the number of reportable accidents being experienced 1995-2000, established a hard target of a 50-percent reduction in the number of reportable accidents during the period 2001- 2005. Having met this target, the industry then established a further target zero for the period 2006-2010. The mechanism to achieve these reductions? The plan-do-check-act model.

Jan 1, 2014

By James Paone

Subsidence movements have damaged houses, schools, streets, and public utility lines in some undermined sections of Belleville and Maryville, Ill. In cooperation with local officials and the State of Illinois, the Interior Department&apos;s Bureau of Mines is sharing experience in backfilling abandoned coal mines to demonstrate that bituminous coal mine workings in south-western Illinois can be successfully backfilled and subsidence-prone areas stabilized. Subsurface investigations revealed that mine workings are dry and underlain by underclay deposits susceptible to instability upon wetting. Backfilling will therefore be accomplished by pneumatic injection instead of the hydraulic methods used in previous subsidence-control projects.

Jan 1, 1977

By M. Moats

Copper electrowinning operations have dramatically improved their ability to produce high quality copper at low costs over the past several decades. Even so, some fundamental understandings are still lacking, which could allow operates to run more efficiently. For example, a rule of thumb exists that estimates a current efficiency loss of 2-3% per gram per liter of iron in the electrolyte. While several laboratory studies have been performed that demonstrate this rule of thumb is likely true, no definitive relationship exists. In this paper, the first steps in developing a definitive relationship are presented. The effective diffusivity of ferric ions in synthetic copper electrowinning solutions was measured using chronoamperometry and the Cottrell equation. The effective diffusivity of ferric ion was determined as a function of electrolyte concentration and temperature. Synthetic electrolytes were then used in laboratory scaled copper electrowinning experiments where relationships were found under stagnant conditions between current efficiency and solution composition.

Jan 1, 2009

By W. J. Spat

Political risk is an integral part of the mining business in northern Andean countries. Peru, Ecuador, Colombia and Venezuela all have a higher than average political risk compared with other South American countries. Successful operations require good political-risk information, a thorough political-risk-management plan and a strategy to deal with political-risk perception on the part of the investing public. Colombia is perceived as about the riskiest place in the world to do business. A selection of recent headlines reads: “Colombia on the brink” (Economist, 1998), “Colombia’s ship of state is sinking” (Insight on the News, 1998), or simply “Bad news” (US Catholic, 1998). The World’s Most Dangerous Places rates Colombia as “currently the most dangerous place in the Western Hemisphere, and perhaps the world” (Aral and Pelton,1998). And many prospective investors and analysts say to Greystar Resources: “Yes, we love your results, but Colombia?”

Jan 1, 2000

By G. Luttrell, S. Keles, M. Eraydin, R. Yoon

The dewatering of fine particles is energy intensive and often requires costly capital expenditures. To address these issues, a series of advanced dewatering technologies have been developed at Virginia Tech. These include novel dewatering aids that enhance the performance of existing filtration equipment and an innovative hyperbaric centrifuge that utilizes both air pressure and centrifugal force for dewatering. The moistures obtained using these processes are 30-50% lower than those obtained using conventional methods. Another dewatering technology, known as the hydrophobic displacement process, can reduce product moistures to a level previously attainable only through the use of thermal dryers. This article presents test results obtained with these various advanced dewatering technologies along with estimates of the power consumption for each process.

Jan 1, 2007

By Carolina Bruecker, Axel Preusse

"The topic of ground movements in Germany has been studied extensively in the past, especially in the field of active mines. The active hard coal mines were finally shut down in 2018 in Germany and lignite mining is expected to take place only until 2038. The so-called long-term liabilities of the mine operators in Germany include, among other things, the long-term guarantee of stability and thus the monitoring of ground motion.So far, the economic use of underground mining in Germany was mainly the supply of raw materials. In the future, the underground storage of compressed air, methane, or hydrogen will play an important role in renewable energy supply and climate change. Therefore, underground storage space will become more important and spatial planning is essential to ensure availability of safe underground openings for the various options of environmentally friendly energy storage.However, this renewed usage of underground openings may also bring new and sometimes unknown challenges of geomechanical influence. On the one hand, the aftermath of hard coal and lignite mining will be an increasing challenge in mining subsidence engineering. On the other hand, new possibilities due to underground spatial planning may lead to subsidence and/or heaving of the upper surface.INTRODUCTIONBoth hard coal and lignite have a long tradition in Germany. The Prosper Haniel mine in the Ruhr area was closed at the end of 2018 after 150 years, which signalled the end of hard coal production in Germany. Lignite mining still takes place in the Central German, Lausitz, and Rhineland districts. However, lignite mining in Germany is expected to be phased out gradually by 2038 (MDR, 2019). With the closure of these mines, however, mining damage is not over. The long-term consequences of mining, which extend far beyond the closure of the mines, are associated with the liability and responsibility of the individual mining companies. The so-called eternity burdens on the mining company continue to apply. In the field of lignite production, the discontinuation of dewatering and the resulting possible elevations of the surface will be a relevant topic for the future of mine surveying. The same applies to the hard coal mines, which are partially flooded in Germany and therefore require extensive monitoring of soil movements in the future.The discontinuation of energy from hard coal and lignite calls for a change in the energy mix. With the renewable energy revolution in Germany, the focus is on a sustainable and environmentally compatible climate and energy policy based on renewable energies. Sustainable use of the subsoil, both natural and anthropogenically produced cavities, will play an essential role in the objectives of this policy. For example, disused mine cavities can be used to store electricity from renewable energy sources. (Umwelt Bundesamt, 2018) These functions will again cause classical ground movements such as subsidence and uplift, but will also bring new challenges for the mine surveyor. Challenges can be underground cavity exploration in inaccessible areas or legal aspects of underground competition."

Jan 1, 2019

By J. Drelich, C. L. White, Ch. Zhou, W. M. Cross, E. T. Zellers, E. M. Nadorny

A laser-based particle deposition (LBPD) technique has recently been developed at Michigan Technological University for patterning mesostructures made of nanoparticles and their clusters. The LBPD technique makes use of laser induced optical forces to transport and pattern nanoparticles on a variety of conductive and non-conductive substrates from nanoparticle-in-liquid suspension. A weakly focused laser beam is used to confine and propel particles along the laser beam. Confinement is accomplished by forces due to optical field gradients that act on polarizable particles and tend to move them to axis of the laser beam. The force propelling the particles along the direction of the laser beam arise from momentum conservation of photons scattered from the particles. In this paper, this novel LBPD technology is briefly reviewed, and several examples of patterning are presented. The size and morphology of mesostrips produced from gold and polystyrene nanoparticles, under a range of deposition conditions, have been characterized by optical microscopy, atomic force microscopy, and scanning electron microscopy. The results presented here demonstrate that gold and polystyrene nanoparticles deposited by LBPD can form clusters of particles. When deposited at an appropriate rate, such clusters can form multilayer mesostrips of high particle density. One goal of research on such systems is to fabricate arrays of parallel lines made up of colloidal particles having a range of surface functionalities. Such arrays have potential for application as novel microsensors for environmental sensors.

Jan 1, 2003

By Stavros H. Constantopoulos

Mediterranean regions such as Greece, Turkey, Cyprus, Corsica and New Caledonia have experienced epidemics of malignant mesothelioma as a result of non-occupational, ??domestic?? exposure to tremolite asbestos and fibrous erionite. This exposure to tremolite asbestos and fibrous erionite is typified ??domestic?? due to its prevalence in regions with natural deposits of tremolite asbestos (or fibrous erionite) where the material from tremolite asbestos or fibrous erionite is used for domestic applications such as whitewashing. However, these exposures may be useful in examining the potential consequences of even small amounts of amphibole asbestos fibers in the ambient air. It can also elucidate the effects of fibers that behave like amphibole asbestos. However, this type of exposure is not useful for studying the potential effects of small amounts of asbestos in the ambient air of big cities due to the differing nature of the fiber types and modes of exposure between the regions. © 2008 Published by Elsevier Inc. Keywords: Tremolite asbestos; Erionite; Domestic; Environmental; Exposure

Jan 1, 2007