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By S. M. Jasinski

Peat is a natural organic material of botanical origin. Peatlands are situated predominately in shallow wetland areas of the Northern Hemisphere. Commercial deposits are formed from the gradual decomposition of plant matter under anaerobic conditions for about 5,000-years. In 2004, peat was harvested in 16 states. Florida, Michigan and Minnesota accounted for more than 80 percent of the U.S. production. Reed-sedge was the dominant variety of peat harvested in the United States, comprising almost 80 percent of the output. This was followed by humus, hypnum moss and sphagnum moss.

Jan 1, 2005

By W. X. Wang

In the mining and quarry industries, rock fragments are often transported by conveyor belt. To estimate the qualities of the rock fragments (i.e., size distribution and shape), an operator must take samples from the conveyor and manually perform a sieve analysis, which is time-consuming and tedious. Alternatively, an image-analysis system can be used to monitor the fragment quality on a fast moving conveyor belt. However, images of fragments on a fast moving belt vary to such a degree that the quality of any two successive images are not the same, and some of the images are of such poor quality that they are unrecognizable by human eyes. If poor-quality images are directly analyzed by a segmentation algorithm, the analysis will not be satisfactory. To resolve this problem, it is necessary to use an image-classification pro-gram for the automatic selection of fragment images with good quality. Because of this need, an image-classification program was developed and tested both in the laboratory and in the field. Testing of the system on different types of fragments showed that the system works reasonably well.

Jan 1, 1996

By S. Hamilton

Borates are essential to life, and to many products that are essential to an acceptable standard of living. They occur naturally in seawater at an average concentration of five milligrams of boron per liter. Fresh water lakes, rivers, streams and ground water generally have concentrations of about one milligram boron per liter. Borates are also present in soil at concentrations ranging from 0.1 to three milligrams of boron per kilogram. Because most of that boron is locked into insoluble minerals, clay or organic matter, boron deficiency is more widespread than boron enrichment. Borates evaporate into the atmosphere from seawater, rain, snow and hot springs. In rain and snow, natural boron concentrations range from 0.002 and 0.1 milligrams boron per liter. All told, boron moves through the atmosphere at a rate of 5 Mt to 7 Mt/a (5.5 million to 7.7 million stpy).

Jan 1, 2005

By P. V. R. Bhaskar Sarma, P. K. Sahoo, G. Roy Chaudhury

A process was developed to treat an ammoniacal leach liquor containing zinc using Di (2-ethyl hexyl) phosphoric acid (D2EHPA) as the extractant. The objective of this work was to develop a process package for the treatment of complex sulfide leach liquors. Zinc extraction could not be carried out directly from the ammoniacal solution in mixer-settler units because of crud formation and low extraction efficiency. After neutralizing the free ammonia with H2SO4, the extraction efficiency was only about 40%, due to the high concentration of (NH4)2SO4. To decrease the (NH4)2SO4 concentration, the free NH3 was steam stripped, and the resultant liquor was subjected to zinc solvent extraction. An extraction efficiency of 98% could be achieved by controlling the equilibrium pH. Stripping studies were also optimized after removing ammonia from the zinc-loaded organic. A continuous 100-hr operation that included extraction, scrubbing and stripping, was carried out successfully.

Jan 1, 1995

By R. Pandey, G. Elie, E. Sarver

Respirable crystalline silica (RCS) is generally considered the most hazardous constituent of coal mine dust, and a new federal rule is expected to further limit exposures in U.S. mines. For regulatory purposes, RCS is monitored by collecting filter samples, which are analyzed for quartz (the predominant form of RCS in coal mines). The analysis is done using Fourier transform infrared spectroscopy (FTIR) in a centralized laboratory. To enable more timely results, National Institute for Occupational Safety and Health (NIOSH) mining researchers developed a directon- filter (DOF) FTIR analysis method and free FAST software that can be used in the field. For samples collected under specific conditions, FAST processes the FTIR spectral data to determine quartz mass. While the DOF FTIR method is not approved for regulatory RCS monitoring, it could be useful for engineering purposes, such as to evaluate mining parameters or new dust controls. This field study demonstrates how the method, including FAST, can be applied using low-cost, widely available sampling components. It further demonstrates how quartz percentage can be estimated in the field, by pairing a continuous personal dust monitor with a filter sampler.

Jun 1, 2025

By Amoussou Coffi Adoko, Shevaune Zeng, Sebastian D’Hyon, Gareth Kennedy, Eleonora Widzyk-Capehart

Inertization of coal dust with stone dust is a common control implemented within underground coal mines to mitigate the hazard of a coal dust explosion. To achieve adequate inertization, the total incombustible content (TIC) of the coal/stone dust mixture is required to meet certain percentages depending on the risk and relevant legislation. Current methods for determining the TIC of a mixture involves laboratory analysis, colorimetric comparison, or the use of portable instruments. This paper provides preliminary analysis of determination of a sample’s TIC in real-time with chemometric modelling, using portable instruments employing near-infrared (NIR).

Feb 1, 2024

By P. Mendoza, R. Siwale, H. Amini, R. Silva, M. Richards, V. Ngcoza, D. Rivera, C. Canaza, R. van Reenen

Development of a realistic flotation model to predict its performance is of paramount importance to the processing plant and operators, a model that accounts for predictive and no-predictive maintenance simulating individual equipment downtime and the effect of it in the metallurgical performance on the flotation bank with final recoveries and grades has a huge advantage on optimizing the flotation circuit/bank in terms of mechanical and metallurgical side. The Model was developed in a dynamic environment that allows for a better and more realistic simulation of the flotation bank. The maintenance model accounts for the Failure rate, Mean Time Between Failures (MTBF), Mean Time to Failure (MTTF) and Reliability (R(t)) those characteristics are combined to a multi-compartment process model that consists of a slurry recovery model, two options of froth recovery models, entrainment and carry capacity as a final check for the system. In addition to the maintenance and process model, a dynamic dart valve model was added to the simulation in order to have a realistic model to control the slurry level at the flotation cell. The paper goes over a study case for a current flotation operation trying to explore all the elements and the simulator to optimize the Rougher flotation bank.

Mar 2, 2022

By S. Rideout

As Assistant Director for Program Support for the Office of Surface Mining Reclamation and Enforcement (OSM), a bureau of the U.S. Department of the Interior, I am responsible for the regulatory and abandoned mine land programs under the Surface Mining Control and Reclamation Act of 1977, which governs the environmental impacts of coal mining. My perspective is influenced by my current position and my previous positions in government and private industry. Sustainability is a cooperative effort of many parties and can only be achieved if each assumes their responsibilities for making it happen. I will highlight some of my thoughts on the role of government in achieving sustainability in the mining arena.

Jan 1, 2007

By F. Segobia, M. Portal, F. Ysla, L. Goicochea

It is our responsibility to promote responsible and sustainable mining with new generations, promoting a culture of equality and respect. To fulfill this commitment, we are working with the SME UNC Student Chapter team, Newmont Yanacocha, BRG Women and Allies and the Museo de Agua y Tierra (MAT) to carry out the “Building our future” project. It is our responsibility to promote responsible and sustainable mining with new generations, promoting a culture of equality and respect. To fulfill this commitment, we are working with the UNC SME Student Chapter team, Newmont Yanacocha, BRG Women and Allies and the Museo de Agua y Tierra (MAT) to carry out the “Building our future” project. This project seeks to instill in new generations the importance of mining, integrating sustainable development objectives. We have the participation of Newmont Yanacocha and external professionals, who share their life stories and inspire participants from rural and urban educational institutions to pursue their dreams and aspirations. We believe that this project is important because it will help new generations understand the importance of mining and its role in the development of the country, covering the economic, environmental and social spheres. Since its inception in 2022, the project has positively impacted more than 500 participants.

Feb 1, 2024

By Karin Bäppler

Hydropower produces almost two-thirds of the world’s renewable electricity generation and delivers a major contribution on the ambition of the Paris Agreement and Sustainable Development Goals (SDG) with a range of benefits to society and environment. These include clean and flexible generation and storage in addition to reduced dependence on fossil fuels and avoidance of pollutants. The Limberg III PSP is one of the European projects that addresses the implementation of the UN SDGs. The challenge of the project is the construction of a 770 m long pressure shaft to be excavated with a TBM at an inclination of 42°.

Jun 13, 2023

By D. A. Poukhovski

Two integral components of the 30 CFR 48 training requirements mandated for new miners, newly employed experienced miners, and the annual refresher training of all miners are hazard recognition and prevention of accidents. In these categories, instruction shall include the recognition and avoidance of hazards present in the mine, and a review of accidents and their causes. Unlike instruction preparation for fact-based material, program development for hazard recognition places a particular challenge before safety-training specialists because they are often limited in their ability to adequately gauge the trainees' levels awareness prior to training. Further, they must also assure that the training is relevant, and it is presented in a thought-provoking manner. Computer-based instruction is particularly well suited for assisting trainers in developing hazard-recognition topics because it can be used in pre-training and post-training modes for assessment of training effectiveness, in addition to use as a presentation tool. Therefore, this paper will present a recent approach developed at Penn State to apply this technology for assessment and instruction of accident prevention through hazard recognition, with an application prepared for surface coal mines.

Jan 1, 1997

By G. L. Hohmann

The Waste Isolation Pilot Plant (WIPP) project is authorized by legislation to provide a demonstration of the safe disposal of radio- active wastes generated by the national defense programs and activities of the United States. The U.S. Department of Energy (DOE) is proceeding with the implementation of the WIPP project in accordance with the "Department of Energy National Security and Military Application of Nuclear Energy Authorization Act of 1980" (PL 95-164).

Jan 1, 1982

By S. J. Cohen

Changes in our energy, national security, and commerce needs have necessitated identification of new sources of minerals, such as rare earths, lithium, copper, silver, aluminum, titanium, and the minerals on the U.S. Geological Survey’s (USGS) list of critical minerals (USGS, 2022). With the need to domestically produce these minerals, more mining will be required within the U.S. Some of these critical minerals deposit with naturally occurring radioactive materials (NORM), therefore, mining these minerals may concentrate NORM to the point that some states may require licensing and radiation protection programs. NORM is not regulated by the Federal government; it is regulated by the individual states. Consequently, overall national state of NORM regulation is chaotic with each individual state either choosing to regulate or not regulate NORM, and, if a state chooses to regulate NORM, then that state develops its own unique regulations. Further complicating the regulatory environment, states utilize a wide variety of strategies for regulating NORM, which sometimes results in inappropriate regulations, inconsistencies with specific radionuclides that are regulated, and inconsistencies with specific NORM types that are regulated. This paper will review the nature of NORM regulations, identify regulatory traps, and provide general guidance for identifying NORM and potentially avoiding regulatory jeopardy. Because of the chaotic nature of NORM regulations nationally, seeking guidance from qualified professionals with relevant expertise is recommended. Also, contacting the appropriate regulatory agency to gain a complete understanding of the NORM regulatory environment is useful for maintaining compliance.

Feb 1, 2023

Eldorado Resources Ltd.(ERL) uses a solvent extraction process for the processing of uranium ores. The solvent extraction plant consists of 4 extraction and 5 stripping stages with regeneration carried out as required (Wyper, 1982). Extraction is carried out with a solvent consisting of 4.5 vol % Alamine 336, 4.5 vol % Isodecanol and 91 vol % kerosene. The extraction step can be represented as In equation (1).

Jan 1, 1988

By W. C. Goldberg, E. M. Frizzell

Monitoring slope displacement in open-pit mines can help predict collapses and prevent serious damage, injuries, and fatalities. Early detection of movement may indicate the need to modify slope geometry, initiate dewatering if the slope is wet, or consider artificial support measures such as cable bolting. Slope monitoring at the Berkeley pit was carried out with varying degrees of intensity and continuity for about 15 years. Some of the old mine records are still intact and accessible. Slope monitoring data can therefore be collected and published for the benefit of other mine operators. Because prediction of slope failures is empirical in nature, publication of several well documented case studies will be a valuable contribution to the industry. Background - Berkeley pit Open-pit mining of copper from the Berkeley pit, located on the east side of Butte, MT, began in 1955 and ceased in 1982. During that time, about 1 Gt (1.2 billion st) of material were removed to form a pit about 1.8 km wide by 2.1 km long (6000 ft by 7000 ft) at the rim, and 550 m (1800 ft) deep as measured from the high hill on the northwest side. From the south side, the pit only measures 365 m (1200 ft) deep. The Berkeley pit was first owned and operated by Anaconda Minerals Co., and subsequently by Arco. Following its closure in April 1982, the mine began to fill with water. Washington Construction purchased the property in 1986, and Montana Resources Inc. began mining to the east of the Berkeley pit in July 1986. Numerous instances of slope failure were recorded during the course of mining and several intensive geotechnical investigations were conducted in an effort to optimize the mine design. One of the last and most comprehensive studies was initiated in 1977. For purposes of geotechnical analysis, the mine was divided into nine design sectors on the basis of geologic conditions, geographic orientation, and economic importance (Fig. 1). Only two of these sectors - the concentrator and the southeast corner - are considered here. Material properties were obtained from several studies of samples collected from the mine and adjacent areas. The slope was monitored using standard surveying techniques to record the amount of movement in an area. The

Jan 1, 1989

By F. Block, K. Kohli

Outcrop barrier pillars serve to keep mine personnel and the public safe from sudden uncontrolled flows of water accumulated in active and abandoned underground mine workings. When an outcrop barrier fails, the result is an outbreak of water to the surface and is termed as blowout. Mine blowouts are associated with above-drainage mines and can occur through the coal outcrop and sealed portals. A blowout is often catastrophic, a threat to the people on the surface living or working in the path of a potentially large flood. In addition, blowouts can destroy homes, cause landslides and severe erosion and release pollution and acid mine drainage. This paper provides guidance on the planning, design, evaluation and inspection of barriers to address the problem of mine blowouts associated with above-drainage coal mines.

Jan 1, 2007

By J. C. Stankus, R. Ochsner, B. Hanson

"Bull Mountains No. 1 mine of Signal Peak Energy made another success in its 4 Right pre-developed recovery entry on March 23 and 24, 2015, after the first successful cut-through and shield retrieval of 3 Right pre-developed longwall recovery entry in 2014[1]. Under the same geological conditions, the major difference of 4 Right and 3 Right is the 600 psi Unconfined Compressive Strength (UCS) value of light-weight concrete in 4 Right versus 800 psi in 3 Right. In addition, one more recovery chute was added in 4 Right. The unique geological conditions in this mine include: (1) the low overburden of approximately 200-260 ft, (2) prevalence of roof joints parallel to the face in the sandstone/siltstone dominated overburden, (3) proximity of the Rehder rider seam to the bench Mammoth coal seam, and (4) prompt surface subsidence with the face advancement. The 4 Right recovery entry was 42 ft wide and developed in two stages, 20 ft wide in the inby Phase I, and 22 ft wide in the outby Phase II. The entry roof was reinforced with steel wire mesh/non-metallic recovery mesh, primary bolts, and high-capacity supplemental SUMO cables. After all the support was installed, the entry was completely backfilled with specially designed, cuttable, low-density cement. It took approximately half time to easily cut through the concrete with less dust in 4 Right as compared to the concrete-cut-through time in the 3 Right. The updated study further explored the nature and mechanism of effective roof control approaches in the pre-developed recovery entry of this unique geology mine, aiming at providing the safest working environment for protecting the miners. GEOLOGICAL AND MINING CONDITIONS OF THE RECOVERY ENTRIES Bull Mountains No. 1 mine is located 30 miles north of Billings, Montana, and currently mines bituminous coal from the Mammoth coal seam. The mine employed a conventional recovery face in Panel #1 and pre-developed recovery entries in Panels #2, #3, and #4 (Figure 1). The typical mining and geological conditions are as follows:Overburden Depth The overburden above the Mammoth coal seam in the #1-#4 Right recovery areas is approximately 200-260 ft. This low cover, in combination with specific roof geological features (especially the prevalent roof joints and proximity of rider seam), constitute unique ground movement characteristics when the longwall face advances into the recovery entry if no sufficient roof support is installed."

Jan 1, 2016

By R. Pinksen

The IOC Mining and Operations Departments expressed an interest in reducing the amount of oversize material (>1.0 m x 1.0 m x 1.0 m; 39 inches x 39 inches x 39 inches) being produced and its subsequent downstream effects including in-pit sorting and reduction, damage to mobile equipment, and significant delays in the loading pockets and the primary crushers. To achieve this goal an oversize reduction project was undertaken by the mine and to date has significantly improved upon baseline measures. One key approach used to reduce the amount of oversize was the implementation of thicker emulsion. The introduction of a thicker emulsion provided more resistance to the forces created by dynamic water and reduces the infiltration of the emulsion into the cracks and fissures of the rockmass. Reduced amounts of oversize and more consistent fragmentation throughout the muckpiles has been a result. Additionally, a significant reduction in nitrates leached into the mine water discharge has been realized. To determine the effectiveness of the oversize reduction project, IOC used a of first-of-kind technology to assess fragmentation presented to the shovel at the digging face. A Digital Vision System (DVS) was installed on one of the shovels to capture images that were stamped with GPS locations. A large population of digital images were analysed to produce a robust fragmentation distribution baseline that was used as one of the mine key performance indicators (KPI). Changes to blasting practice were subsequently measured against the baseline KPI to assess effectiveness.

Jan 1, 2011

By J. Harrison Daniel

Were the legislators and politicians responsible for the closing of the U.S. Department of the Interior?s Bureau of Mines (Bureau) in March 1996 fully aware of what they were doing? Throughout the United States? history, the domestic mining and minerals industry has been largely responsible for the nation?s growth and prosperity that had made it a world leader. The mining and minerals industry made it possible for the young nation to catch up with Europe during the Industrial Revolution, played an essential role leading to victories in World Wars I and II and was a core ingredient for continued economic growth. For a number of decades, America?s import dependency on non-fuel mineral materials has continued to increase. (USGS Mineral Commodity Summaries). Developing domestic resources to meet current and future demands ? particularly those resources considered to be of strategic and critical value to national security ? is necessary. Federal involvement is required since many of these resources are located on public lands. Another reason for federal involvement is that the success of the industry depends on long-range research programs and advances that may take up to 25 years to become commercially available. This situation requires federal partnership to coordinate the programs necessary to collectively involve the industry, individual mining companies and colleges and universities. So, how was it possible to close a federal agency that had contributed so much to the nation?s welfare in a mandated 90-day period, with more than 1,200 employees losing their jobs?

Jan 4, 2010

By Aaron Jones, Guy Reed, Russell Frith

"In 2017, one of the international authorities on coal bursts, Dr. Chris Mark, published a paper entitled “Coal Bursts that Occur during Development: A Rock Mechanics Enigma,” in which several relevant technical issues were identified, the most pertinent being:i.whilst development coal bursts are commonly associated with geological faults, understanding which specific faults result in burst-prone development mining conditions and why, remains undefined.ii.conventional wisdom in relation to strong roof and floor geology of the coal seam might be limiting, based on certain burst examples in Colorado.iii. development coal bursts can occur without the local ground stresses being substantially elevated from their in situ levels.This paper outlines what is considered to be a credible, first-principles, mechanistic explanation for these three current development coal burst conundrums by reference to early published coal testing work examining the significance of a lack of “constraint” to coal stability and an understanding of how very specific structural geology and other geological features can logically cause this to occur in situ, albeit on a statistically very rare basis. This basic model is examined by reference to published information pertaining to the development coal-burst that occurred at the Austar Coal Mine in New South Wales, Australia, in 2014 and from the Sunnyside District in Utah, USA.The “cause and effect” model for development coal bursts presented also offers a meaningful explanation for the statistical improbability for what are nonetheless potentially highly-destructive events, being able to explain the statistical rarity being just as important to the credibility of the model as explaining the local conditions associated with burst events.The model could also form the basis for a robust, risk-based approach utilising a “hierarchy of controls” to the operational management of the development coal burst threat. Specifically, these include the use of pre-mining predictions for likely burst-prone and non-burst-prone areas, the use of the mine layout to avoid or at least minimise mining within burst-prone areas if appropriate, and finally the development of an operational Trigger Action Response Plan that reduces the likelihood of inadvertent roadway development into a burst-prone area without suitable safety controls already being in place."

Jan 1, 2019