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By K. E. Livo, D. H. Knepper

Modern remote sensing provides a means for locating and characterizing exposed mineralized systems in many parts of the world. These capabilities are non-invasive and help target specific areas for more detailed exploration. An example of how remote sensing technology can be used is evident from a study of the Questa Mining District, New Mexico. Analysis of low spectral resolution data from the Landsat Thematic Mapper satellite system clearly shows the region-al distribution of two broad mineral groups often associated with mineralized systems: clay-carbonate-sulfate and iron oxides-iron hydroxides. Analysis of high spectral resolution data from the Airborne Visible and Infrared Imaging System (AVIRIS) shows the occurrence and distribution of many individual mineral species that characterize the pattern of hydrothermally altered rocks in the district.

Jan 1, 2004

By L. F. Ruppert, P. A. Freeman, R. C. Milici, S. J. Tewalt, L. J. Bragg

The U.S. Geological Survey has completed a dig-ital coal resource assessment of six of the top-producing coal beds and coal zones in the northern and central Appalachian Basin coal regions. These include the Pennsylvanian-aged Pittsburgh, Upper Freeport, Lower Kittanning, Fire Clay, Pond Creek, and Pocahontas No. 3 coal beds and coal zones. Resources were calculated on all of the coalbeds/zones, with the exception of the Lower Kittanning coal bed. Preliminary original resources are estimated at about 93 billion short tons (84 billion tonnes), of which about 66 billion short tons (60billion tonnes) remain. Much of the remaining coal in all five coal beds/zones is thinner [<3.5 ft (1.07m)] and deeper [>1,000 ft (305 m)] than the coal that has been mined, but economic resources are still available and mining in each coal bed/zones will continue throughout this decade and into the next given current market conditions.

Jan 1, 2001

By Daniel F. Meyer

INTRODUCTION The Metropolitan Boston Transit Authority (MIA) Red Line has served greater Boston commuter needs from its Harvard Square terminus since its opening in 1912. Since then, the population of Boston&apos;s northwest area has increased substantially, and with this growth have come dramatic changes in the type and distribution of urban land uses, including the number of households, jobs, shopping and recreational opportunities; these changes have created a need for improved transportation. Extension of the Red Line to better serve these communities has been a topic of discussion for nearly 40 years. In November of 1977, the Urban Mass Transportation Administration (UMTA) granted the MBTA approval and funding for the Red Line Extension Project. With funding in place, the MBTA proceeded with final engineering and construction of the section from Harvard Square to Alewife. When completed, the Red Line Extension will add 3.2 miles of new track to the MBTA system. Estimated final cost is about $400 million. On October 3, 1978, the MBTA received bids for the construction of Project 091-105, Harvard Square to Porter Square Tunnels and Shafts, which is part of the overall Red Line Extension. The Joint Venture of Morrison-Knudsen, White, Mergentime was the low bidder at $47,478,600. Official award of the contract came on October 25, 1978, with Notice to Proceed given October 31, 1978. The contract called for construction of two independent parallel concrete-lined tunnels in rock, soft-ground and mixed-face

Jan 1, 1983

By E. Siami-Irdemoosa, S. R. Dindarloo

Ease of excavation or rippability, also called diggability or excavatibility, is a critical decision-making parameter in the selection of both the overburden removal method and the required equipment in surface mining and geotechnical engineering projects. The most widely used method of estimating rippability is rock mass classification. Although there are different classification schemes in the literature, all of them have the two major limitations of sharp transitions at class boundaries and subjective uncertainties in decision making. In this study, the decision trees method was employed as a classification tool for estimating ground rippability, using the four rock mass parameters of weathering degree, uniaxial compressive strength, joint spacing and bedding spacing. The results were compared with those of the widely used method of diggability index rating (DIR) and a fuzzy-based DIR. The problem of subjective uncertainty was resolved in the proposed decision trees method, as the tree rules were derived automatically from the training data sets. Compared with fuzzy-DIR, a decision tree classifier is simpler, needs less computational time and is more appreciable by industry practitioners. Nevertheless, the proposed method is not flawless and, similar to both the conventional and fuzzy DIR methods, yielded poor estimations in particular instances. The limitations of the three methods are discussed.

Jan 1, 2015

By J. Humphries

With today?s turbulent markets and unprecedented global opportunities, the need to optimize net present value and internal rates of return from capital investments has never been greater. To help address the need, this paper presents an overview of the key processes and strategies for achieving maximum return from capital projects. Best practices discussed address stage gate management for project evaluation, selection, and oversight, project execution efficiency, value improving practices, operational readiness, and operational excellence. The paper also includes a model of key metrics and benchmarking with tips for application. [ ]

Jan 1, 2011

By Rolando Gonzalez

Mexico’s role in the world economic community continues to grow. And it is important that the country makes use of its natural wealth, including its large underground deposits of minerals and metals. With that in mind, Industrias Peñoles S.A. de C.V.(Peñoles), a mining, smelting and refining company, began mining lead, zinc and other metals from the Francisco I. Madero Project (FIM). The mine is located about 600 km (370 miles) northwest of Mexico City in the state of Zacatecas. Peñoles plans to remove about 3 Mt/a (3.3 million stpy) of ore from FIM. To achieve this goal, the company needs to optimize its processing, to maximize the amount of metal it extracts through FIM’s large flotation lead-zinc concentrator. To ensure high productivity, Peñoles and its contract engineering firm, M3 Engineering and Technology, of Tucson, AZ, have implemented anore processing system.

Jan 1, 2003

By D. Scott Scovira, Thomas Gustavsson

Exiting WW2, the potential of nitrates and hydrogen peroxide for application as industrial explosives both became known. The technology stream advanced the development and uptake of nitrate-based explosives to the point that they are the current global standard for blasting. Recently environmental issues are influencing the strategic agenda of extractive industries. The mid-2010s saw renewed interest in hydrogen peroxide explosives to eliminate NOx fume. Carbon reduction initiatives in the 2020s provided additional impetus to investigate hydrogen peroxide-based explosives. Hypex Bio is at the forefront of developing and delivering bulk gas sensitized Hydrogen Peroxide Emulsion (HPE) for blasting. HPE consists of hydrogen peroxide along with smaller amounts of fuel and emulsifier. The consistency of HPE is similar to industry- standard nitrate-based emulsions. It is compatible with existing priming and initiation systems. HPE does not contain nitrates and thereby does not produce post blast nitrous oxide fumes nor discharge of nitrates or ammonia to mine water. Importantly, HPE contributes to reduction in total carbon emissions as compared to nitrate-based explosives.

Feb 1, 2025

By Albert Ruiz

The 2,250-MW, coal-fired Navajo Generating Station located in Page, AZ draws water from Lake Powell using submersible pumps installed in five inclined shafts. Drought threatens to lower the reservoir to below the existing intakes. A system of new steel-lined intake shafts located on the same site was required for uninterrupted plant operation. The small size of the site, and the need to keep the existing system in operation, required detailed designs and placed significant limitations on construction equipment and activities. The Navajo Sandstone that forms the near vertical shoreline of the reservoir is 98 percent very fine grained quartz, highly abrasive and contains highly fractured intervals that presented numerous challenges to drilling the new 152-m (500-ft) deep, 109-cm (43-in.) diameter intake shafts inclined 23° to 26° from vertical. Spatial constraints, submersible pump design and operational criteria required that each shaft have a unique inclination and orientation and hit a small breakout target located 76 m (250 ft) under water. Sophisticated drilling equipment and techniques as well as state of the practice downhole survey technology and methods were used to make adjustments and maintain drilling accuracy with less than 1 percent deviation. Environmental requirements mandated water as the drilling fluid and grout was not allowed in to the lake under any circumstances. The shafts were videotaped and the breakout locations were examined using an underwater remotely operated vehicle (ROV) to verify shaft locations and rock conditions, and to guide placement of pneumatic packers to ensure grout did not transmit to the lake during the steel liner installation. In anticipation of the invasion of quagga mussels, the shaft design included an allowance for a chemical dosing system and a copper-rich alloy at the exposed portions of the steel liner.

Jan 1, 2011

By M. Bennett, L. Twidwell

Montana Tech has embarked on a coordinated series of studies to delineate the characteristics of the Berkeley Pitlake containing over 36 billion gallons of acidic, metal-contaminated water formed after the cessation of open-pit copper mining in Butte, Montana, USA. The objectives of the overall series of studies are to summarize presently available information and to generate new and needed information to formulate a conceptual environmental model for the pitlake and to provide characterization data for the development of advanced treatment technologies. In this presentation, the chemistry of the Berkeley Pitlake water is partially reviewed. It is known that the pitlake consists of two distinct layers of water referred to as surface and deep water. Samples of deep water were collected and placed in a 12-ft high and 6-inch diameter column and exposed to different wavelengths of UV radiation as well as atmospheric conditions. Measurements of pH, redox potential (EH), dissolved O2, turbidity, conductivity, temperature, and elemental composition show that the water reacts differently and indicates that the diurnal effects of sunlight likely play a major non-biological role in its chemistry. Resulting technology could be useful for developing an alternative to treating acid-rock drainage.

Jan 1, 2007

By P. Fauvel, V. Nasri

In January 2001, French and Italian governments signed an agreement for the construction of a new Lyon-Turin railway line. This project includes a tunnel of 53.1 km length and a maximum of 2500 m overburden to be designed for a reference speed of220 km/h. The tunnel crosses major part of the West Alpine geological formations, which are very complex and contrasted in terms of the nature of rocks and the mechanical and hydrogeological conditions. In addition to the twin single-track tubes, numerous intermediary shafts, security station and intervention sites and cross passages should be built to respond to the security, operational and construction requirements. This paper describes the results of the preliminary engineering design and multiple challenges of this very long and deep railway tunnel.

Jan 1, 2005

By S. Panigrahi

The SO2-ammoniacal ammonium sulfate leach liquor generated by leaching of manganese nodules, after removal of minor quantities of iron and manganese, contained copper, nickel, cobalt, zinc and (NH4)2SO4. After extraction of copper from the leach liquor with LIX 84I, stripping of ammonia from the Cu-barren raffinate was carried out followed by precipitation of metal ions from the ammonia-stripped solution as sulfides. Leaching of the sulfide precipitate was carried out with H2SO4 to obtain a leach liquor containing 0.58 kg/m3 Cu, 2.67 kg/m3 Zn, 2.00 kg/m3 Co, 24.68 kg/m3 Ni and 10.0 kg/m3 (NH4)2SO4. After extraction of copper and zinc from the sulfate leach liquor with LIX 84I and D2EHPA, respectively, the solution was left with Co and Ni. Extraction of cobalt from the Cu- and Zn-free solution was carried out with 0.1 M PC88A and stripping of the cobalt-loaded organic was carried out with the cobalt-spent electrolyte (pH 1.4). Extraction of nickel from the cobalt-free solution was carried out with 90% neutral 1M NaPC88A followed by stripping of the nickel-loaded organic with 120 kg/m3 H2SO4 solution. Extraction of metal ions increased with increasing equilibrium pH and extractant concentration. The maximum separation factors, with respect to the pH and extractant concentration variation studies, were 3796.7 and 15350.0, respectively. The extracted species for the metal ions were CoA2?3HA and NiA2?5HA.

Jan 1, 2009

Safety is the No. 1 concern of any drill contractor or mine operator. Everyone in the industry knows a safe site helps stabilize operational costs and enables higher productivity. When it comes to exploration drilling, research has proven a majority of injuries are caused by the mishandling of coring rods. A driller helper will typically handle up to 50 rods per shift or up to 15,000 rods per year. With an annual 340 t (750,000 lb) in rods managed by hand, the risk of serious injury is extremely high. Because of this, the top request from the exploration industry is diamond rod handling. The Boart Longyear 4200 surface exploration drill, slated for release in 2009, will give the industry a hand-free, operationally safe rig.. Developed through the collaboration of its global drilling services and products divisions and targeted at the 1,200-m (3,900-ft) NQ market, the upcoming Boart Longyear 4200 surface exploration drill features the safest and most flexible rod management sys-tem in its class. The rig includes the industry?s first, truly hands-free rod handling system. This increases operator safety on the jobsite. In addition to the rod handler, the rig also features many new innovations that boost productivity and rig efficiency while minimizing the risk of downtime due to component failure or operator error. Boart Longyear has also included an intelligent PC-based operating system designed to allow complete drilling control as well as diagnostics reporting for the rig.

Jan 1, 2009

By Bhaskar B. Thapa

The proposed Caldecott fourth bore will consist of a two lane highway tunnel along California State Route 24 near the City of Oakland. The proposed design and construction sequence for the 15-m-diameter tunnel are based on the New Austrian Tunneling Method (NATM). The initial support system incorporates combinations of shotcrete, rock dowels, lattice girders, spiles, and grouted steel pipe canopies. The final lining is cast-in-place reinforced concrete. A waterproofing membrane and drainage system are placed between the initial and final linings. State Route 24 is a lifeline route, required to be open to emergency vehicles within 72 hours after a major earthquake, defined as having a return period of 1,500 years and a peak ground acceleration of 1.2 g. Although the seismic design criteria are stringent, the design of the tunnel lining system is ultimately controlled by static ground loads in the weak rock along the alignment.

Jan 1, 2008

By FELIPE SÁNCHEZ, PHILIPP HARTLIEB

Innovation plays a critical role in the mining industry as a tool to improve the efficiency of its processes, to reduce costs, but also to meet the increasing social and environmental concerns among communities and authorities. Technological progress has also been crucial to allow the exploitation of new deposits in more complex scenarios: lower ore grades, extreme weather conditions, deeper deposits, harder rock mass, and high-stress environments. This paper discusses the importance of innovation for the mining industry and describes the mechanisms by which it is carried out. It includes a review of the drivers and actors involved and current trends. The digital transformation process that the industry is going through is analyzed, along with other relevant trends that are likely to shape the mining of the future. Additionally, a case study is presented to illustrate the technical and economic implications of developing a disruptive innovation project.

Jul 23, 2020

By Edward Thomas

Yucca Mountain Overview The U.S. Department of Energy?s Yucca Mountain Project is a geologic repository project designed to receive, handle, package, transport, and emplace spent nuclear fuel and high level radioactive waste. The planned repository would be located in Yucca Mountain on the western edge of the Nevada Test Site, about 90 miles northwest of Las Vegas, Nevada, and would include both surface and subsurface areas. Yucca Mountain rock formations consist of successive layers of volcanic rocks (called tuffs) approximately 14 to 11.5 million years old, formed by eruptions of volcanic calderas to the north. With the volcanic rock the potential for methane emission is not an issue and the subsurface repository is a non-gassy (methane) classification. This paper will provide a summary of the development ventilation system design that provides fresh air for subsurface construction activities, and the emplacement ventilation system design that removes heat generated by the waste packages. The subsurface layout, illustrated in Figure 1, contains 108 emplacement drifts, one Performance Confirmation(PC) observation drift, nine intake/exhaust shafts, and three access ramps. The existing Yucca Mountain facilities, shown in bold lines in Figure 1, include a 7.8 km long, 7.62 m (25 ft) diameter U shaped tunnel that is formed by the North and South Ramps at both ends of the Exploratory Studies Facility (ESF) drift and a 1.5 km long, 5.0 m (16.4 ft) diameter Enhanced Characterization of the Repository Block drift (ECRB) that were constructed from 1994 through 1998. These drifts were used for site characterization activities and have been incorporated into the subsurface repository configuration. The unexcavated perimeter access main and exhaust main drifts are typically 7.62 m (25 ft) diameter TBM excavations and the emplacement drifts are 5.5 m (18 ft) diameter TBM excavations. The turnouts leading into the emplacement drifts are to be excavated by either mechanical, or drill and blast methods and serve as the launch chambers for the emplacement drift TBM excavations.

The Barrick Zaldivar mine is an openpit, heap-leach copper mine in Region II of northern Chile at an elevation of 3,300 m (10,826 ft), approximately 1,400 km (870 miles) north of Santiago and 175 km (109 miles) southeast of the port city of Antofagasta. In 2006, Zaldívar produced 307 million lbs of copper, with reserves estimated at 5.7 billion lbs. The mine uses conventional methods of openpit mining: Pure cathode copper is produced by three stages of crushing and stacking the ore, followed by heap leaching and bacterial activity to extract copper from the ore into solution. A solvent extraction and electrowinning process then removes the copper from solution and produces the cathode copper. A flotation plant also recovers copper contained in the fine fraction of the crushed ore. In 2006, an existing A-frame structure that covered copper ore from the mine?s secondary crushing operation was damaged beyond repair. The material delivery configuration of this original structure had the conveyor carrying incoming ore directly over the low roof to drop ore into the building at its peak, and ore trickling from the sides of the conveyor had accumulated on the roof, overloading it. A better solution had to be found, and fast: First, the Chilean Commission does not permit uncovered piles of this type since the extremely fine material leads to serious pollution problems. Second, Barrick Zaldivar is very concerned about worker safety, and the amount of dust created by the uncovered pile was not acceptable. Finally, some amount of copper was lost in the dust generated by the winds of the Andes. The major issues faced by Barrick Zaldivar in designing a new structure included:

Jan 1, 2009

The MineSight Schedule Optimizer (MSSO) is a new production scheduling tool developed by Mintec, Inc. using mixed integer linear programming (MILP) techniques. This tool was developed to solve the short- and medium-term schedule problems for surface and underground mining operations that involve multiple mining areas, multiple processes, multiple destinations and blending requirements. MSSO finds the optimum schedule in each period that achieves the objective while satisfying comprehensive product quality and quantity requirements as well as physical and technical constraints. Using the MineSight Planning Database (MSPD) as a central data hub, MSSO seamlessly works with MineSight 3-D (MS3D) block models and third-party data, MineSight Interactive Planner (MSIP), MineSight Haulage (MSHaulage) and MineSight Activity Planner (MSAP) to prepare data, formulate MILP models, calculate, report, fine-tune, save and visualize schedules. This paper presents the features and capabilities of MSSO. A case study is also given to demonstrate the applications of this new tool.

Jan 1, 2009

Introduction Aggregate mining impacts on water resources are a source of concern to local governments. To evaluate those impacts, the Minnesota Department of Natural Resources conducted a four-year study at three gravel pits (two alluvial and one beach-ridge) and five quarries (flat-lying Paleozoic limestone). This research provides the first comprehensive look at aggregate mining impacts on ground-water systems in Minnesota. The results will be used by government officials making permitting decisions about aggregate operations and by responsible owners of aggregate mines as they plan their operations to avoid conflicts with neighbors and with resources dependent on ground water and surface water. Natural aggregate (crushed stone, sand, and gravel) is a vital part of our economic infrastructure in Minnesota. Aggregate is used for road and bridge construction and in a variety of building materials. In 2003, the value of construction sand and gravel and crushed stone in Minnesota was approximately $245,000,000. As Minnesota’s economy continues to expand, the demand for aggregate will continue to grow. Sand and gravel pits are located in every county in Minnesota. In 1990, the Minnesota Department of Natural Resources, Division of Minerals (DNR Minerals), estimated the number of active and inactive operations at 1500 with the view that this number was likely too low. Quarries for mining limestone, dolomite, sandstone, and hard rock (granite and quartzite) are found in 34 counties. A 1990 DNR Minerals inventory found 165 active operations, 88 percent of which were limestone quarries (Nelson and others, 1990). That same inventory counted 1,367 inactive operations, 70 percent of which were limestone quarries. Aggregate mining is an extractive use of resources: mining alters the landscape and its natural hydrologic system. When a new pit or quarry is proposed or when an existing operation needs to expand, local governments and citizens typically have many questions about the impacts mining might have. Local governments, which are responsible for reviewing these operations, rarely have the budgets to hire experts to evaluate potential impacts of quarry and gravel pit proposals. The Minnesota Legislature’s Aggregate Resources Task Force identified that local government units (LGUs) often lack the expertise to assess ground-water models (Southwick and others, 2000).

Jan 1, 2007

By William R. Yernberg

The “China & East Asia Mineral and Energy Re-sources Symposium — CEAR 2000” was held Jan. 23-26, 2000 in Denver, CO. Conference sponsors included Resources and Technology Symposia of Colorado and the Asian Journal of Mining. The meeting was attended by representatives from China, Japan, Mongolia, Korea, eastern Russia (Siberia) and the United States. The US attendees consisted of interested parties from mining and energy companies, financial institutions, consultants and government agencies. In his opening statements, L. Maness, Jr., president of Resources and Technology Symposia of Colorado, said that the “goal of the conference was to make jobs and friendships and to introduce people to each other.” The conference provided an opportunity for Western mining interests, including mining companies and investors, to meet with government agencies from both sides of the Pacific.

Jan 1, 2000

Editor’s note: As usual, the June issue features an industrial minerals review. And some thanks are in order. Thank you to the industrial minerals annual-review editor, to the technical committees chair and vice chairs and to the authors of the individual commodity profiles. Jim Norman of GeoTrans Inc. is the industrial minerals annual-review editor. Lucy McCartan, US Geological Survey, was the chair of the SME industrial minerals technical committees. She also served as the vice chair for agricultural minerals. Other technical committee vice chairs were: •Gary Tomaino, Specialty Minerals Inc., ceramics and refractory materials. •Srinivas (Vas) Veeramasuneni, US Gypsum, chemical raw materials. •William Langer, US Geological Survey, construction materials. •Vanessa Santos, Independent, fillers and pigments. •Richard Berg, Montana College of Mineral Science and Technology, specialty minerals. Their help makes possible this June industrial minerals issue. On behalf of the readers, the editors thank them.

Jan 1, 2002