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By T. Murt, C. Oñate

In recent years, environmental considerations have played a prominent role in underground construction projects. The management and disposal of the muck produced by an EPB TBM is an important aspect of this topic. Soil conditioners with higher biodegradability and lower eco-toxicity have been specifically developed to comply with strict regulations in several countries around the world, with the goal of reducing the environmental impact of tunneling on soil, water, and living organisms. This paper highlights innovative sustainable soil conditioners and how they differ from traditional products. Additionally, environmental considerations for TBM projects around the world and in North America will be examined.

Dec 1, 2022

By A. Martikainen, S. GYAMFI

Luossavaara-Kiirunavaara Aktiebolag’s (LKAB) Konsuln iron ore mine, located just south of the famous Kiruna iron ore mine in Malmfälten in northern Sweden inside the Arctic Circle, was developed as a test mine between 2018 and 2020 for the Sustainable Underground Mining (SUM) project [1]. Besides functioning as a test mine, Konsuln also contributes to ore production. The existing mine ventilation system was designed for the current production rate of 0.8 Mtpa using conventional diesel machines. The design was created by Kiruna mine ventilation team, Stina Klemo and Joakim Jonasson, in cooperation with a consultant, Tomas Bolsöy from EOL Vent Mining AB. There is a plan to increase this rate to between 1.8 and 3 Mtpa in the future, and this requires the primary fans to be upgraded. Therefore, a study was carried out to determine whether using ventilation on demand (VOD) could avoid this fan upgrade and reduce Konsuln’s ventilation and heating power costs in the future. The study also investigated whether using battery electric vehicles (BEVs) along with VOD or as a standalone strategy could further reduce these power costs. In addition, the study analyzed the suitability of heating power reduction strategies presently or previously used in Nordic countries and Canada to investigate potential additional strategies to reduce heating power cost, the largest portion of Konsuln’s ventilation and heating power costs.

By W. J. Miles

Oil based drilling fluids utilize a number of industrial mineral products to accomplish oil and gas drilling in several environments where water based drilling fluids are less effective or inappropriate. These industrial minerals include: organically modified bentonite, organically modified lignite, barite, hematite, mica, calcium chloride and other salts. A variety of organic products are also utilized in oil based drilling fluid formulations. Oil based drilling fluids are preferred in several drilling situations because: they can be used to drill through water sensitive formations; they produce holes that are very close to the drill bit gauge; they exhibit high temperature stability; they are more environmentally acceptable; they minimize producing formation damage; they provide faster drilling rates when used with new polycrystalline diamond drill bits; they minimize pipe sticking and lost rig time.

Jan 1, 1986

By Nik Sokol, Mike Jaeger, Leo C. Weiman-Benitez

Silicon Valley Clean Water signed a progressive-design-build (PDB) contract with Barnard Bessac Joint Venture (BBJV) to design and construct the Gravity Pipeline tunnel in Redwood City, CA. Owner and Design-Builder teamed with designer Arup to provide a final product: 3.3 miles of 182 in. O.D. precast concrete segmentally lined tunnel with 10 ft. and 11 ft. I.D. Fiberglass Reinforced Polymer Mortar (FRPM) carrier pipe, complete with two FRPM Drop Structures. BBJV and Arup collaborated with SVCW to evaluate alternative design concepts, negotiate an agreeable price and reduce contingencies through a transparent estimating process, and deliver the project ahead of schedule.

Jun 13, 2023

By A. K. Stagg

Toxic substances in On solutions can retard biological leaching of copper sulfide dump ores. On solutions were analyzed for metals, organics, and chloride, and showed inhibitory concentrations of aluminum, manganese, and chloride. Inhibition of bacterial activity by the solid fraction of On solution, with and without the organic constituents, was evaluated. Toxicity to bacterial species was evaluated by monitoring bacterial numbers, pH, Eh, and rates of iron oxidation. The On solution solids were toxic at 50 -60% of their field concentration. Most of the toxicity of the On solution was due to the organic fraction. Different SX reagents show varying degrees of inhibition of T. ferrooxidans. Bacterial inhibitory effects of carriers and lixiviants used in the SX plant should be determined so that entrained SX reagents do not retard biological dump leach systems. The reagents used should be the most cost effective and the least toxic.

Jan 1, 1994

By M. Polat

Variations in flotation rate by particle size and specific gravity have been investigated for three different bituminous coals. The flotation rates for various components were determined by separating the products of bulk flotation into size-specific gravity fractions. The effects of feed size and reagent addition on the flotation response of individual size-specific gravity fractions were evaluated.

Jan 1, 1994

By N. A. Karl, D. R. Wilburn

"This summary of international mineral exploration activities during 2017 draws upon information from industry sources, published literature, SNL Metals & Mining (SNL), an offering of S&P Global Market Intelligence (New York, NY) and specialists in the U.S. Geological Survey (USGS) National Minerals Information Center. Three types of information are reported and analyzed in this annual review of international exploration: 1) budgetary statistics expressed in U.S. dollars provided by SNL; 2) regional and site-specific exploration activities that took place in 2017 as compiled by the USGS and 3) regional events and legislation that affected exploration activities including economic, social and political conditions, which were derived from published sources and discussions with USGS and industry specialists. Commodity and regional compilations are presented in this summary. Because multiple sources were used to develop commodity and regional compilations, statistics may vary depending on the source and type of data that are being reported.The SNL data summarize budget estimates for worldwide exploration activities in 2017 for 30 nonfuel mineral commodities and metal alloys, based on company surveys. Surveys focused on precious metals (gold, platinumgroup metals (PGMs) and silver), base metals (cobalt, copper, lead, molybdenum, nickel, tin and zinc), bulk commodities (bauxite, chromite, iron ore, manganese, phosphate and potash), and other commodities (aluminum, antimony, diamond, graphite, heavy-mineral sands, lithium, niobium, rare-earth elements (REEs), scandium, tantalum, tungsten, uranium, vanadium and yttrium). Information on uranium exploration activities was included in SNL’s survey for the first time in 2007. Data on lithium, niobium, phosphate, potash, REE and tungsten were compiled for the first time in 2010, and scandium, vanadium and yttrium were added in 2014 because of their increased topical significance. Since 1999, companies with exploration budgets of $100,000 and greater were included in the SNL surveys. SNL budget estimates exclude coal, and oil and gas. The 2017 SNL mining company survey compilation was reported by SNL to include an estimated 95 percent of the world’s nonfuel mineral exploration budgets. The 5 percent that was not covered was accounted for by companies that chose not to participate in the SNL survey, private companies that do not publish their budget data, and government-funded exploration activities."

Jan 5, 2018

By N. A. Karl, D. R. Wilburn

"This summary of international mineral exploration activities for the year 2016 draws upon information from industry sources, published literature, SNL Metals & Mining (SNL), an offering of S&P Global Market Intelligence (New York, NY), and specialists in the U.S. Geological Survey (USGS) National Minerals Information Center. Three types of information are reported and analyzed in this annual review of international exploration: 1) budgetary statistics expressed in U.S. dollars provided by SNL; 2) regional and site-specific exploration activities that took place in 2016 as compiled by the USGS and 3) regional events and legislation that affected exploration activities including economic, social and political conditions, which were derived from published sources and discussions with USGS and industry specialists. Commodity and regional compilations are presented in this summary. Because multiple sources were used to develop commodity and regional compilations, statistics may vary depending on the source and type of data that are being reported. The SNL data summarize budget estimates for worldwide exploration activities in 2016 for 30 nonfuel mineral commodities and metal alloys, based on company surveys. Surveys focused on precious metals (gold, platinumgroup platinumgroup metals (PGMs) and silver), base metals, (cobalt, copper, lead, molybdenum, nickel, tin and zinc), bulk commodities (bauxite, chromite, iron ore, manganese, phosphate and potash) and other commodities (aluminum, antimony, diamond, graphite, heavy-mineral sands, lithium, niobium, rare-earth elements (REEs), scandium, tantalum, tungsten, uranium, vanadium and yttrium). Information on uranium exploration activities was included in SNL’s survey for the first time in 2007. Data on lithium, niobium, phosphate, potash, REE and tungsten were compiled for the first time in 2010, and scandium, vanadium and yttrium were added in 2014 because of their increased topical significance. Since 1999, companies with exploration budgets of $100,000 and greater were included in the SNL surveys. SNL budget estimates exclude coal, and oil and gas. The 2016 SNL mining company survey compilation was reported by SNL to include an estimated 95 percent of the world’s nonfuel mineral exploration budgets. The 5 percent that was not covered was accounted for by companies that chose not to participate in the SNL survey, private companies that do not publish their budget data and government-funded exploration activities."

Jan 5, 2017

By G. van Eck, H. Smit, L. Meyer

The Cook Islands (CI) possesses within its Exclusive Economic Zone (EEZ) a massive field of polymetallic nodules representing one of the world’s largest undeveloped cobalt deposits, along with large quantities of other metals critical to achieving global energy transition targets. In February of 2022 the Seabed Minerals Authority (SBMA) of the CI granted Moana Minerals a license to conduct our nodule exploration program. This paper describes how Moana Minerals chose to approach conducting exploration activities, one of the greatest challenges to Deep Sea Mining (DSM) development and the securing of the social license to advance to eventual mining of the resources, in an unconventional manner. The remote location of the project poses logistical challenges in mobilizing to and operating in the region and is a significant cost driver. Historically, exploration campaigns mobilized large vessels from mainland Europe, the Americas, and Asia as this model works well when contemplating long duration and widely temporally spaced campaigns without the need to revisit. Moana Minerals, when considering these challenges determined a multi-year deep sea mining (DSM) exploration program conducted in such a remote location can be better optimized by the deployment of a smaller yet highly capable “exploration optimized” vessel that is dedicated to the task and is based full time in the Cook Islands. INTRODUCTION The paper describes the challenges of exploration in remote regions including the South Pacific, and how an unconventional consideration of the problem led to the solution. Completion of an Environmental and Social Impact Assessment begins with a detailed environmental scoping study, resource update sampling requirements, and engineering data and sample requirements, which identifies the exploration goals of the project and technology needed to accomplish those goals. The method walks the reader through vessel and technology selection, discusses the challenges of equipment selection considering size and capability, describes the final arrangement, and provides results from the initial exploration campaigns. We followed the project from conception through the shipyard conversion, mobilization, and initial operations in the Cook Islands. The result shows how a smaller vessel with limited budget makes a large impact on the exploration capabilities in the region while building public trust. The Anuanua Moana is the first dedicated deep sea minerals exploration vessel modified with a suite of technologies that allow it to compete technically with existing ships but operate locally in the smaller ports of the South Pacific. The unique combination of size and technical capability gives the Anuanua Moana advantages over other vessels. This paper shows the importance of the Anuanua Moana in the development of offshore exploration strategies in the emerging deep sea minerals space.

Feb 22, 2026

By C. P. Boddy

One of the most difficult tasks a project manager will have in pre-mine planning is dealing with the mine site's hydrologic regime. Numerous federal statutes passed by Congress in the last decade have made the coal mining industry more responsive to the environmental impact during all phases of the mining process. Permitting these mines has dictated a cradle to grave approach in dealing with water related issues. This paper will attempt to explore the application of these technology- based laws and their direct application to the unique environment found in Alaska's interior regions.

Jan 1, 1985

By A. Chieregati

"A heterogeneity study was conducted at Erdenet Copper Mine in Erdenet, Mongolia, to determine the fundamental sampling error associated with blasthole sampling. Using a custom-designed radial sector sampler , six large blasthole samples were collected to perform the test developed by Pierre Gy to estimate the constitutional heterogeneity factor for several types of ore. The study investigated the entire sampling protocol, from mine site to analytical laboratory, and quantified the contributions to total fundamental sampling error (FSE) of the various stages of sampling and sample preparation. The total relative standard deviation (RSD) of sampling error was determined to be ±32 percent and ±49 percent for copper and molybdenum, respectively. A classical statistical analysis conducted on the data confirmed the level of RSD native to the mine. About 95 percent of the sampling error was produced from one step in the sampling protocol, that of reducing the 1-kg (2.2-lb) sample to a 50-g (0.1-lb) sample for chemical analysis. To minimize the FSE, the use of a slightly different protocol is recommended. The 1-kg sample (2.2-lb) should first be crushed to a 0.2 cm (0.08 in.) particle size. A 250-g (0.5-lb) split should then be taken and finely ground, from which a 50-g (0.1-lb) split should then be taken. These simple steps will reduce the FSE to ±7.9 percent and ±17 percent for copper and molybdenum, respectively. The modified sampling protocol effectively reduces to zero the probability of misclassification of low-grade ore. IntroductionThe Erdenet copper-molybdenumopenpit mine is located in Erdenet in Orkhon province, Mongolia. The Erdenetiin-Ovoo copper-molybdenum deposit is 1.5 to 3 km (0.9 to 1.8 miles) wide and about 25 km (16 miles) long (Erdenet Mining Corp., 2016). Chalcopyrite, bornite covellite and chalcocite are among the major minerals found in the deposit. The mine processes approximately 26 Mt/a (29 million stpy) of ore."

Jan 11, 2017

"A commercially available through-the-earth (TTE) communications system was evaluated at an active underground longwall mine in West Virginia. This TTE system uses electricfield (E-field) sensing to send text-based communications through two separate antenna arrays connected in parallel. Each antenna array is composed of interconnected, grounded metallic rods or other such structures. Two-way communication between subsurface locations was investigated in this study using various antenna configurations. This field study was conducted as a part of a larger multisite evaluation of available TTE systems in an effort to determine their operational sensitivities. IntroductionWireless, through-the-earth (TTE) communication technology is designed to achieve point-to-point communication through solid strata using very low frequency (VLF) and ultra-low frequency (ULF) electromagnetic waves. Using this approach, communications are established without the need for intermediary communications infrastructure. As a result, TTE systems have the potential to provide reliable, robust communications between surface and underground personnel. Exploration into the use of TTE technology for this purpose dates back to the 1920s (Jakosky and Zellers, 1924; Pittman, Church and McLendon, 1985), but U.S. permissibility requirements slowed the development of TTE equipment for widespread implementation (Durkin 1980; Pittman, Church and McLendon, 1985). One of the primary challenges in producing wireless TTE communications is the counteraction of signal attenuation when propagating through solid strata (Barkand, Damiano and Shumaker, 2006; Wadley, 1949). The long wavelengths of TTE transmissions make them well-suited for reducing the rate of attenuation. However, even when operating within the VLF to ULF range, the performance of TTE systems is still affected by geologic and anthropogenic factors (Geyer, 1973; Geyer and Keller, 1976; Geyer, Keller and Ohya, 1974; Jakosky and Zellers, 1924; Large, Ball and Farstad, 1973). Although commercially developed TTE systems have demonstrated the ability to communicate in a variety of conditions, their range and performance have been highly varied (Barkand, Damiano and Shumaker, 2006; Geyer and Keller, 1976; Geyer, Keller and Ohya, 1974; Ilsley, Freeman and Zellers, 1928; Jakosky and Zellers, 1924; Yenchek et al., 2012)."

Sep 1, 2016

By Kevin Andrews, SETAREH GHAYCHI AFROUZ

Ground control analysis and groundwater inflow assessments for underground coal mines require in-depth field investigations including, but not limited to, geological and geotechnical core logging, downhole geophysical logging, laboratory rock strength testing, and packer (Lugeon) testing. Field and laboratory data collection are time consuming and expensive, and an initial understanding of the expected trends among various geotechnical and hydrogeological parameters can assist with the planning and optimization of geotechnical characterization studies and grouting plans. In this study, a comprehensive database is analyzed, comprised of important rock mass characteristics (hydraulic conductivity, rock quality designation (RQD), and lithology) for coal-bearing rocks in the Central Appalachian Basin. Statistical analysis of the data is completed to establish an enhanced understanding of geotechnical and hydrogeological conditions expected to be encountered as underground coal mining passes near and beneath streams and rivers. The results of the study provide valuable reference material for the coal mining industry for completion of shaft installations, mine stream crossings, environmental assessments, and grouting and mine dewatering designs.

Jul 1, 2023

By J. R. Sturgul

Computer simulation models of working mines can be of great benefit to the mining engineer. Such models have been used in mine planning (how many trucks/shovels to have, when to add new equipment, etc.), mine design (should a dispatch system be purchased, where is the optimum location for mine equipment, etc.). A simulation model can be thought of as a dynamic representation of the mine and can easily be changed to reflect a wide variety of different situation. Often a major problem for the engineer is how to present the results of the simulation study. Using PROOF(R) animation it is now possible to interface the results of the simulation and project them onto a computer screen in cartoon fashion.

Jan 1, 1993

By Richard L. Sanford

This paper summarizes the results of the development of a Directory of Computer Programs Applicable to U.S. Mining Practices and Problems. The Directory is funded by the U.S. Bureau of Mines and includes a sampling of computer usage in operating and manufacturing companies, consulting firms, computer companies, research organizations, universities, and various U.S. government agencies. General references to computer applications throughout the mining industry are discussed as well as the availability of programs to interested organizations or individuals.

Jan 1, 1978

By Sam M. Pickering

Most high, purity silica is produced from crystalline quartz-generally from sand. However, there is a small area of southern Illinois where a porous, friable white chert rock is found which is very different in physical form from quartz sand. This microcrystalline material, commonly referred to as tripoli, is more easily ground to micron sizes than sand. Although of similar Moh's hardness, microcrystalline tripoli is less abrasive than either ground quartz sand or many synthetic abrasives. Location The southwestern corner of Illinois is underlain by extensive deposits of very porous chert; in some places the material is quite white. Two companies - Illinois Minerals Co. and Tammsco, Inc. - mine and process this white material. The Illinois Minerals plant is located at Elco, and the Tammsco plant is in Tamms, Illinois. Both companies mine from various locations within a ten mile truck haul of their plants. Production from this district has been continuous since at least 1915. Malvern Minerals Company mines and processes a generally similar microcrystalline, friable novaculite near Hot Springs, Arkansas.

Jan 1, 1985

By C. Arthur Lefler

The Smoky Valley Mine is jointly owned by Louisiana Land and Exploration Company, Felmont Oil Corporation and Case Pomeroy Company. Copper Range Company, a subsidiary of L.L. & E. is the operator of the mine. The mine is located about 60 miles (100 km) north of Tonopah, Nevada on Highway 376 (formerly 8A) in the Big Smoky Valley on the western flank of the Toquima Mountain Range In the shadow of Mount Jefferson. The mine is at an elevation of about 6100 ft. (1860m) and is situated on the southwestern flank of Round Mountain, the hill for which the town of Round Mountain is named. The ore is a rhyolitic iglmbrite with coarse gold occurring along fractures and with fine microscopic gold disseminated in the rock mass. Minor silver is associated nth gold. Annual mining is planned at 5.8 million tons (5.3 million tonnes) per year with 2.2 million tons (2 million tonnes) as ore (7,000 tons or 6,400 tonnes per day).

Jan 1, 1981

By John R. Turney

MARY KORPI: Harry Hinds will be filling in for John Turney today. Harry is an exception to the industry these days, in more ways than one. He has worked for the same mining company for 33 years. That is something very few of us can claim. He is currently metallurgical superintendent for Homestake Mining Company in Lead, South Dakota. Harry is also the envy of many of us as he will be retiring this year and working on lowering that handicap! Harry will be discussing the "Role of Consultants."

Jan 1, 1998

By J. J. Bartels

The phosphate rock review did not arrive in time for publication in the. June issue. The world phosphate industry continued its slide in 1992 from the already depressed levels in 1991. The industry is locked into a 30-year fertilizer price low due to the worldwide fertilizer glut. Domestic production and imported, marketable phosphate rock decreased 1%, while domestic consumption increased by 1 % last year. The US Bureau of Mines reported a decrease in the domestic phosphate rock value from $25.42/t in 1991 to $23/t in 1992 ($23.06/st to $20.80/st). The diammonion phosphate (DAP) product price also dropped in value from $138/ t in January 1992 to $11 0/t in December ($125/st to $99.70/st). Continued declines in DAP prices is forcing the US fertilizer industry to develop cost-saving programs and reorganizations. Layoffs in 1992 resulted in a 7.6% decrease in the Florida phosphate workforce. Since 1980, the Florida workforce has declined by 35%. Small phosphate companies were forced to close operations or were sold to larger phosphate companies. Federal and state environmental regulations for byproduct waste disposal methods are being studied. The Environmental Protection Agency (EPA) approved phosphogypsum use in agri¬cultural and research applications as long as the radium 226 concentration is lower than 10 pci/g. The EPA is also reviewing regulations concerning air emissions at fertilizer plants. Industry publications reported the possibility of continued company sales and mergers in 1993. Industry expectations are optimistic while waiting for an upturn in the market. The US phosphate industry consolidation into three or four major companies should evolve into a stronger world market force.

Jan 1, 1993

By A. Anderson, G. May, C. Kubank, S. Meik

The Kori Kollo operation is owned by Empresa Minera Inti Raymi S.A., a Bolivian mining company. Inti Raymi is an eighty-five percent owned subsidiary of Battle Mountain Gold Company (BMGC). The remainder of Inti Raymi is held by Zeland Mines S.A., a Bolivian mining company. The project is located near the village of La Joya, approximately 220 km south of La Paz, and 40 km north west of Oruro on the Bolivian altiplano. Inti Raymi started a heap leach operation in 1985. By 1988, following several expansions, 4,000 tonnes per day of oxide ore were being treated. At this time drilling was started to delineate the larger sulfide orebody. A feasibility study for the development of this deposit was completed in 1990, and following project approval, the engineering design was started later that year. During this period orders were placed for the major items of mechanical equipment. In July 1991, Minproc Engineers Inc. was awarded a firm price contract to design and construct the 14,000 tonne per day sulfide ore process facility.

Jan 1, 1993