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By Megan Badonie, Devlon Shaver, Evan J. Owen, Virginia T. McLemore, Jakob Newcomer

Critical minerals are becoming more important in our technological society because they are used in many of our electronic devices, batteries, and magnets. In New Mexico, low to moderate concentrations of critical minerals are found in Late Cretaceous coal and related strata in the San Juan and Raton Basins. These rocks are being characterized as part of the DOE’s CORE-CM (Carbon Ore, REE, and Critical Minerals) program. The New Mexico coal, humate, and clinker deposits are relatively low in REE (<325 ppm TREE), Li (<90 ppm), V (<168 ppm), Co (<51 ppm), Ni (<108 ppm), Zr (<557 ppm), and many other critical minerals compared to normal economic deposits. Some of these rocks are enriched in Al2O3 (<40%) and Sr (<3740 ppm), both critical minerals. Common minerals hosting the critical minerals in these rocks include clay minerals, zircon, and rutile/anatase. As the demand for some of these elements increases because of increased need and short supplies, the dollar value per ton of ore rises, enhancing deposit economics. Ultimately, economic potential will most likely depend upon production of more than one commodity, maybe even from coal, humate, and clinker deposits.

Feb 1, 2024

A unity of viewpoint emerged from the workshop. The concept that transmission is via characteristic modes was a common theme in many of the presentations. Also, the confusion an the meaning of monofilar and bifilar to describe these dominant modes was cleared up. But, there was still a healthy divergence of opinion on what constitutes an optimum system. It was generally agreed that further analytical and experimental work is definitely needed. In particular, it was stressed that independent measurements of the constitutive properties of the electromagnetic environment are needed. Also, there was considerable concern that laboratory measurements of rock samples could lead to misleading results for the effective conductivities. Also, there was a general recognition that over simplified propagation theory should not be used to interpret field data. From a theoratical and practical point of view, it was realized that mode coupling plays a vital role in the transmission channel. One must not only understand which and how many propagation modes are excited by the transmitting antenna, but the conversion of energy from one mode type to another must be accounted for. This conversion can either be done intentionally (by fixed mode convertors) or non intentionally (by random wall roughness). In fact, mode conversion can be quite complicated when various propagation paths exist such as when insulated cables, leaky feeders, grounded rails, coal seams, etc. all convey portions of the electromagnetic energy. However, this state of affairs should be regared as an. opportunity for extended communication coverage in mines rather than a limitation of a desig. procedure based on preconceived notions of the dominant propagation mechanism.

Jan 1, 1978

By Evan J. Owen, Virginia T. McLemore

Rare earth elements (REE) and critical minerals are increasingly becoming more important in our technological society and are used in many of our electronic devices (such as cell phones, computer monitors, wind turbines, etc.), batteries, and magnets. Measuring REE and critical minerals in ashed coal approximates the REE and critical minerals in the fly or bottom ash remaining after coal is burned at a power plant, where REE and other critical minerals could be leached. In New Mexico, there are 26 coal fields in Late Cretaceous rocks in the San Juan and Raton Basins. These rocks are being characterized as part of the DOE’s CORE-CM (Carbon Ore, Rare Earth, and Critical Minerals) program. Higher concentrations of REE (as much as 2103 ppm total REE) are found locally in ashed coals from the basins. More chemical and mineralogical analyses are required to fully understand the distribution and origin of REE in these deposits. As the demand for REE increases because of increased need and short supplies, the dollar value per ton of ore rises, enhancing deposit economics, perhaps even from coal.

Feb 1, 2025

By K. Cole, D. Mesa, P. Brito-Parada, M. R. van Heerden

Turbulence in mechanical flotation cells, achieved via an impeller, plays a key role in keeping particles in suspension, dispersing air bubbles, and promoting particle-bubble collision. However, studying the hydrodynamics of a flotation cell is not a simple task, due to the complex nature of flotation systems which are opaque, turbulent, multiphase and polydisperse in terms of particle and bubble sizes. In this paper we study the impact of impeller design modifications on the hydrodynamics of a continuously overflowing bench-scale flotation tank. To this end, two different impeller designs, with and without a stator, were assessed using Positron Emission Particle Tracking (PEPT). This allowed the authors to determine, for the first time, the effect of an impeller design on the behaviour of both hydrophobic and hydrophilic particle tracers. It was experimentally observed that the use of a stator modifies the hydrodynamics within the flotation cell, distorting the lower mixing loop that is characteristic of axial impellers. The role of the stator in dissipating turbulence results in reduced particle velocities outside of the impeller-stator region. These results have important implications for flotation cell design and are discussed in the context of the impact that different designs have on particle movement, flotation hydrodynamics and, ultimately, flotation performance. The data set generated is also extremely valuable for modelling and validation purposes. Keywords: Flotation, flotation tank, impeller design, rotor, stator, PEPT, hydrodynamics

Jan 1, 2020

The wealth of a nation may be measured in many ways, but one of the most important is its natural resources, particularly its minerals. Minerals create the wealth upon which economic prosperity and defense preparedness rest. Managing mineral resources for the benefit of all Americans continues to be an important national goal. In its 78-year history the U.S. Bureau of Mines has established itself as the world&apos;s premier mineral information and research agency. Its authoritative, comprehensive data and pioneering research have contributed significantly to a strong U. S. mineral position in the world.

Jan 1, 1988

By Sean Gallagher

This report was written in an effort to provide better control measures for low back pain (LBP) and low back disability in the mining industry. There are numerous factors associated with development of LBP, many of which can be effectively controlled while some cannot. Better job design is promoted as the best method of reducing cases of LBP and can also reduce the disability (i.e., lost time from work) associated with LBP when it happens. The report draws attention to what is currently known about LBP, what the causes are thought to be, and discusses recent back injury trends in the mining industry. Research describing unique physical demands in mining, such as the capabilities and limitations of working in awkward postures, is also presented. Methods that can be used to prevent initial LBP episodes are provided, including facilities design and layout for materials and supplies, use of mechanical-assist devices, improved design of lifting tasks, and better seat design. Methods of reducing the disability associated with LBP (including workplace design, proactive return-to-work efforts, communication, and management commitment) are also discussed. The report concludes that control of LBP and disability in mining requires a comprehensive approach to limit the repetitive loading that can occur on the low back due to manual materials-handling tasks and exposure to whole-body vibration (WBV). Specific recommendations include the following: ? Successful LBP prevention efforts require a proactive program that has strong management commitment and incorporates employee involvement. ? More efficient supply handling systems and use of mechanical-assist devices can greatly reduce exposure to hazardous lifting tasks. ? Lifting tasks should be designed to minimize low back stress. Tools to evaluate and redesign lifting tasks are presented. ? Improved seat design can reduce exposure to WBV and improve posture, leading to reduced LBP risk. ? The disability associated with LBP can be reduced. Getting the worker back on the job as quickly as possible is in the interest of everyone involved.

Sep 1, 2008

By NORA Mining Sector Council

The National Occupational Research Agenda (NORA) is a partnership program to stimulate innovative research and workplace interventions. In combination with other initiatives, the products of this program are expected to reduce the occurrence of injuries and illnesses at work. Unveiled in 1996, NORA has become a research framework for the National Institute for Occupational Safety and Health (NIOSH) and the United States. Diverse parties collaborate to identify the most critical issues in workplace safety and health and develop research objectives for addressing those issues. NORA entered its third decade in 2016 with an enhanced structure. The 10 sectors formed for the second decade will continue to prioritize occupational safety and health research by major areas of the U.S. economy. In addition, NORA’s seven cross-sectors will continue to focus on the major health and safety issues affecting the U.S. working population. While NIOSH serves as the steward to move this effort forward, it is truly a national effort. NORA is carried out through councils comprised of members with many diverse interests that are developing and implementing research agendas for the occupational safety and health community over the third decade (2016-2026) of NORA. Councils address objectives through information exchange, partnership building, and enhanced dissemination and implementation of evidenced-based solutions. NORA groups industries into 10 sectors using North American Industry Classification System (NAICS) codes. The Mining Sector encompasses NAICS code grouping 21xxxx where “xxxx” represents the different subcodes of the mining “21” classification. Mining encompasses the extraction of solid mineral and mineral-like substances from their place in the Earth’s crust and supplies them to processing industries that produce economically valuable materials. It does not include oil and gas extraction. The Mine Safety and Health Administration, MSHA separates mining into coal, underground and surface, and metal and nonmetal, underground and surface.

Feb 1, 2024

By Charles G. Howard

Accidents involving underground rail transport were analyzed to quantify the magnitude and the operational requirements for individual mine car braking systems. The results showed that the brake preventable accidents represent only 2% of the total underground fatal accidents and less than 1% of the total underground nonfatal accidents. In addition, the brake preventable accidents are expected to decline over the next decade. The costs of accidents involving deaths and Injuries were determined using various well accepted methods. The costs of a brake retrofit program for all operating underground coal cars were developed separately for small and large coal mines. Costs of retrofit brakes, new car brakes, maintenance, inspection and repair facilities were included in the esimates. The analysis showed that a retrofit program would not significantly increase safety, and that the program cost would greatly exceed the corresponding expected benefits.

Jan 1, 1979

This report is in fulfillment of Contract H0230031 awarded to Bituminous Coal Research, Inc., on May 23, 1973. The scope of work to be performed under this contract was divided into four phases: Phase I - Design, Phase II - Construction, Phase III - Field Demonstration, and Phase IV - Analysis and Final Report. During Phase I, an agreement was finalized with the Rochester and Pittsburgh Coal Co. for conducting field tests of the proposed shearer spray systems on a longwall panel in the company&apos;s Jane Mine in Indiana County, Pa. A drum was then designed which could be used on the Eickhoff shearer, Model EW170-L, being used on this longwall and which would utilize the following spray systems: 1. One spray nozzle located in front of each cutter bit with the jet directed at the cutting surface. 2. One spray nozzle located in back of each cutter bit with the jet directed at the back of the bit. 3. Standard Eickhoff nozzles located in a header along the drum scrolls. 4. A fixed header mounted on the shearer directly behind the drum to simulate the spray system originally used on the Eickhoff shearer.

Jan 1, 1976

By R. Ward Stahl

Fire has been one of man&apos;s most useful tools through the ages and certainly is a "must" for industrial progress but when uncontrolled is one of the most destructive agencies. This fact is even more important in a coal mine, where many persons and much expensive equipment are confined in a relatively small area. Means of escape from a burning area, as well as from the products of combustion, are often limited; and in many instances the entire surroundings are combustible. Numerous mine fires, which resulted in a high death toll and great financial loss through the years, have caused mine owners to search for the best fire-fighting equipment; much of this has been installed, the quantity depending largely upon the experience of the individual companies or neighboring mines in certain coalfields. A mine owner or operator has meager published information on the actual fire protection afforded and systems of fire-fighting inaugurated in the coalfields, by which he could compare his efforts and get some idea of the adequacy of his own protection. To further general knowledge of the subject, it was decided to survey a representative number of mines in the field and show what has been accomplished. Representative mines were selected in various coal beds; some had similar tonnage, so comparison could be made if desired.

Jan 1, 1957

This briefing was sponsored by the Bureau of Mines to summarize ongoing and recently completed chromium-chromite research and resource assessment activities by the Bureau. Through the series of 18 presentations compiled herein, Bureau personnel covered a wide range of topics including U.S. chromite and chromium trends and usage patterns; foreign and domestic resources; and research activities on mineral characterization and beneficiation, chemical and pryometallurgical processing of chromite and chromium-bearing wastes, new low-chromium alloy and coating substitutes, corrosion- and oxidation-resistant stainless steels, and chromium-containing refractories.

Jan 1, 1986

By J. Drimmer

The past several decades have seen the rapid expansion of multinational mining companies? exploration and production activities around the globe. This trend has resulted from a number of factors, including increased demand for resources as a result of worldwide economic growth, the diminishment of known and proven reserves, rising commodity prices, technology improvements, and the liberalization of investment regimes in developing countries with significant natural resources. With those opportunities, however, come associated risks and significantly increased legal compliance obligations that may be imposed by various bodies. That includes domestic regulations, as well as foreign civil and criminal laws with extraterritorial reach. A failure to adhere to those laws can have dire consequences, including substantial monetary fines and penalties, severe damage to a company?s reputation, and even jail time for individual company employees.

Jan 1, 2010

By P. T. Bissert, J. P. Ducarme, J. D. Noll, C. C. Jobes

"There have been about 42 fatalities in underground coal mines between 1984 and 2015 where the victim was struck, pinned, or run over by a mobile machine (MM) such as a shuttle car, scoop, or battery hauler. MSHA has issued a proposed rule requiring proximity detection systems (PDS) on MMs in an effort to prevent future fatalities. Currently approved PDSs use electromagnetic (EM) technology to detect the presence of a miner and impose machine controls to prevent contact. The disadvantages of an EM-based PDS on MMs include the need for a miner-wearable component (MWC), environmental interferences, EM interferences from other devices, and low localization range and accuracy. NIOSH researchers are investigating alternate technologies that could improve the capabilities of the current PDSs. Many technologies were reviewed, and NIOSH researchers identified RFID, LIDAR, RADAR, ultrasonic detection, and computer vision as candidates for PDS development. The performance characteristics of each technology and its applicability to an underground mining environment will be discussed, along with international developments and implementations, and the concept of sensor fusion. INTRODUCTION PDSs provide safety to mine workers by detecting their presence (and in some cases location) around a machine. These PDSs provide a warning zone, which triggers an alarm, and a stop zone, which halts the machine before it contacts the miner. The Mine Safety and Health Administration (MSHA) issued a final rule requiring that PDSs be installed on all continuous mining machines (CMMs) on the working section, with the exception of full-faced machines, according to a phase-in schedule for newly manufactured and existing equipment [1]. The PDSs that were designed for CMMs have since been adapted to other mobile machines. Mobile machines include scoops, which are used as general utility vehicles, as well as coal hauling machines, such as shuttle cars, ram cars, and continuous haulage systems. MSHA has examined all accident reports from 1984 to 2014, and determined that 42 fatalities could have been prevented on mobile machines had a PDS been installed [2]. As such, MSHA issued a proposed rule that would require mobile machines on working sections (with the exception of longwall sections) to be equipped with a PDS. This rule would follow a phase-in schedule for newly manufactured and existing equipment. Currently available PDSs are based on electromagnetic (EM) technology. NIOSH researchers developed a shell-based magnetic flux density distribution model [3] for determining the position of a miner near a machine. A typical system would consist of four generators positioned around the perimeter of the machine. Each generator is a coil of insulated wire wrapped around a ferrite core. The magnetic field strength is proportional to the current running through the coil. Miners working on the section have an MWC, which is a transceiver that measures the field strength emitted by the generators and transmits a data packet over an RF link which contains the field strength reading to the PDS controller mounted on the machine. The magnetic field generators are pulsed sequentially such that the MWC can identify which generator’s field strength it is reading. This type of system utilizes the principle of magnetic flux density: the closer the MWC is to the field generators, the higher the field strength reading. Thus a miner’s presence can be determined once he gets too close to the machine, because his MWC will measure a magnetic flux density beyond a certain threshold. These thresholds are utilized on a per-generator basis to “shape” the fields for both warning and stop zones around a machine, as illustrated in Figure 1."

Jan 1, 2017

By R. L. Grayson

Using powerful database management software, nested-field analysis and microanalysis of narratives have been made of West Virginia accident data, resulting in a new approach for targeting and prioritizing safety interventions by county, mine size, specific mine, job title, type injury, etc. and combinations of these parameters. The analyses have been useful in focusing training and discussion sessions on specific work problems, trends, conditions, and situations for targeted groups of miners. Application of the technique will be presented in this paper, along with comparisons of various mine performance measures.

Jan 1, 1997

By M. M. Ayoub

With a return to coal as a major energy source for many companies, more emphasis is being placed on recovery of coal from areas that were formally considered uneconomical to mine. Increasing emphasis is being placed on production from low coal (seam height 48 inches or less) as high coal seams are depleated. Mining in restrictive spaces requires unusual work postures that can turn easy jobs into demanding ones. The objectives of this research were: (1) to evaluate the job demands associated with low coal mining, (2) to survey the anthropometry, strength, and aerobic capacity of low coal miners to determine if they differ from the U. S. population, and (3) to recommend, on the basis of available information, optimal job and work station design for low coal mining. This research effort was supported by the U. S. Bureau of Mines. The male and female anthropometry with the exception of weight and circumferential dimension, was quite similar to the comparison population. Back strength for male and female miners was significantly lower than the industrial worker population. This can be one of the contributing factors of low back problems in mining. Shoveling, timbering, and helpers tasks were physiologically demanding activities. However, due to the frequent stoppage of work, adequate rest was usually available. If work stoppage is corrected, then better work/rest schedules are essential.

Jan 1, 1981

By Henry P. Cole

A comprehensive review of published research was carried out to identify methods for teaching and assessing critical but nonroutine skills needed for coping with emergency situations. Specific methods for assessing critical skills proficiency in aviation, medicine, organization management, the military, and other industrial/technical workplaces are described. The potential application of these methods for teaching and assessing (1) critical first aid and (2) self-rescue and escape skills to underground coal miners in annual refresher training is explored. Research and development activities that may improve mine health and safety training are suggested. Most of these research and development activities were completed later in the project. This additional work is reported in the project technical report #2 and the final report. The research reported in the present document was completed in 1984 -85. Many of the initial findings reported in this document are updated in the later project final report.

Jan 1, 1988

By F. H. Touwen, N. C. Joughin

"Simulation is a technique for studying the operation of systems by synthetic experimentation. With digital computers it is possible to simulate even the complex production processes in gold mining. This has great potential in that it enables the investigation, analysis and comparison of mining systems to be done accurately, rapidly and at low cost. Two programs have been developed to simulate the principal underground production processes in gold mining.These are the simulation of any stope contract and the simulation of underground transport operations. The programs synthesize these mining activities from a large number of small unit operations. The stope contract program simulates rockbreaking by drilling and blasting and the cleaning of the panels by face and gully scraping. The transport program simulates the functions and movements of all vehicles running on rails on one underground level. The simulation programs provide an effective means for experimenting with mining activities."

Jan 1, 2014

By Jared Winkler, Jon A. Hummer, Aleksandar D. Bugarski, Shad Peters, Steven E. Mischler, Steve Cochrane, Shawn Vanderslice, Teresa Barone

The case study assessed submicron aerosols at a continuous miner (CM) section, diesel aerosol concentrations at the longwall (LW) section, and elemental carbon (EC) and total carbon (TC) exposures. Aerosols at CM sections were a mix of freshly generated and those from main drifts. Low ambient concentrations and personal exposures suggest effective control strategies, with further reductions possible by curbing emissions from high-emitting light-duty vehicles.

Mar 16, 2022

These proceedings consist of papers presented at three Bureau of Mines Technology Transfer Seminars on ergonomics in the mining industry. These seminars were held in December 1981, and covered topics relating to ergonomics and mining in the areas of the man-machine interface, and design of the work environment. This area of research is directed toward reducing accidents traditionally associated with human error.

Jan 1, 1981

By Terry J. Close

Between 1986 and 1989, at the request of the U. S. Bureau of Land Management, personnel from the U. S. Bureau of Mines Western Field Operations Center studied the highly-mineralized, 25,335-acre, Crack Canyon Wilderness Study Area (UT-060-028A), to evaluate its identified mineral resources. The 16-mi-long, 2-mi to 4-mi-wide stud/ area is on the southeast side of the San Rafael Swell, about 40 mi southwest of Green River, Emery County, southeast-central Utah. The study area is underlain by Mesozoic sedimentary beds. Uranium, the principle mineral resource, occurs in two formations. The principle uranium deposits are in mudstone, sandstone, and conglomerate lenses in the 22-mi-long outcrop of the Triassic Chinle Formation which parallels and straddles the northwest boundary of the study area, Some small low-grade uranium occurrences and an extensive gypsum deposit are hosted by the Jurassic-age rocks that underlie the southeast part of the study area.

Jan 1, 1989