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By Frank Hagar, George M. L. Robinson

INTRODUCTION Mine waste monitoring and management is essential when the industry is being required to accept the environmental liability for all generated, stored and disposed solid and hazardous waste. Environmental regulations mandate the operator to minimize waste production while requiring the operator to cleanup existing contamination. Since these requirements are being enforced, many operators do not have a clear under- standing, whether their existing operation will or could be required to adopt remedial plans to mitigate off-site contamination impacts. The following methods, using conventional and advanced geostatistical methods, provide a tool to make appropriate assessments whether existing or potential contaminant issues are present. BACKGROUND Generated solid wastes from mining operations are currently exempt from Solid Waste Disposal Act (SWDA) Sub- title C (RCRA), statutes and promulgated regulations, however, compliance with SWDA Subtitle D statutes and regulations is required. In order for the mining operator to be exempt from hazardous waste regulations, the operator must demonstrate that generated waste does not have hazardous waste characteristics. In many instances the operator will be able to use statistical tools and their existing data to determine whether their site could be a potential hazardous waste liability. METHODS The following statistical and geostatistical methods can be used to determine whether existing wastes could be a regulatory concern. The following presents a brief discussion of standard statistical methods and discusses, in greater detail, how advanced geostatistical tools can be used to define potential waste issues. The following will discuss how data can be screened, "Data Filtering and Reporting"; how data can be evaluated using "Conventional Statistics"; followed by a detailed discussion o f "Geostatistical and Estimation Techniques" and "Statistical Modeling". Data Filtering and Reporting Data filtering is the simplest, but potentially the most powerful statistical tool because data can be easily sorted to meet regulatory reporting requirements. Filtering includes unions and intersections of data such as date, maximum and minimum values of one or several variables. Using the data base presented in "Mine Waste Data Base Management Procedures", Robinson and Hagar, 1987, an example of a filter group is presented.

Jan 1, 1987

By David B. McWhorter, John D. Nelson

INTRODUCTION The quantity of seepage that will be released from a tailings impoundment depends not only on the characteristics of the seepage control system, but also on the properties of the foundation soil or rock beneath the impoundment and the nature of the groundwater in the area. The interaction between various elements of the seepage control system and the influence the various characteristics of the site and impoundment have on seepage are the subject of this paper. The results of analyses are presented herein to indicate the nature and magnitude of the effect that the various factors will have on seep¬age losses. Analyses were conducted for a uranium mill tailings impoundment located in an area characteristic of many found in the western United States or Canada. A typical seepage control system consists of placement of either a clay or synthetic liner beneath the impoundment. In some cases an underdrain system may be placed on top of the liner to collect drainage from the tailings. The parameters that were varied in the analyses included those pertaining to the liner, underdrains and foundation strata. In general, it is shown that the seepage losses will vary in a complex manner depending on the interaction of the elements of the site and the seepage control system. As may be expected, the liner and underdrain systems have the most pronounced effect on controlling seepage. This paper deals with the quantity of seepage released from an impoundment However, the impact that seepage losses from an impoundment will have on the surrounding environment will depend on the rate at which contaminants will enter the groundwater and the nature of the groundwater flow itself. Consequently, when considering these results with regard to environmental impact they must be interpreted along with considerations of geochemical factors. MECHANICS OF SEEPAGE The mechanics of seepage and methods of analysis that were used will be discussed briefly herein. For a more detailed discussion the reader is referred elsewhere (McWhorter and Nelson, 1978, 1979, 1980). A general column through the impoundment was considered to be as shown in Fig. 1.

Jan 1, 1980

By William H. Langer

Nearly every community in the United States is dependent on aggregate (sand, gravel, and crushed stone) resources to build and maintain its infrastructure. Unfortunately, developing aggregate resources to meet societal needs causes environmental impacts. Most environmental impacts associated with aggregate mining are benign. Extracting aggregate seldom produces acid mine drainage or other toxic effects commonly associated with mining of metallic or energy resources. The most obvious environmental impact of aggregate mining is the conversion of land use, most likely from undeveloped or agricultural land use, to a hole in the ground. This major impact is accompanied by loss of habitat, noise, dust, blasting effects, erosion, sedimentation, and changes to the visual scene. Some of the impacts are short-lived, and most are easy to predict and easy to observe. Most impacts can be controlled, mitigated, or kept at tolerable levels and can be restricted to the immediate vicinity of the aggregate operation by employing responsible operating practices and available technology. The intensity of environmental impacts generated as a result of mining are determined in large part by the geologic characteristics of aggregate deposits (geomorphology, geometry, and physical and chemical properties). Mining deposits that are too thin, or contain too much unsuitable material, results in the generation of excessively large mined areas and large amounts of waste material. Mining aggregate can lead to serious environmental impacts in some situations. Some geologic environments such as active stream channels, slide-prone areas, and karst terrain are dynamic and respond rapidly to outside stimuli including aggregate mining. Some geomorphic areas and (or) ecosystems underlain with aggregate serve as habitat for rare or endangered species. Similarly, some geomorphic features are themselves rare examples of geologic phenomena or processes. Mining aggregate might be acceptable in some of these areas, but should be conducted only after careful consideration, and then only with extreme prudence. Failure to do so can lead to serious, long-lasting, and irreversible environmental consequences, either in the vicinity of the site or at locations distant from the site. Environmental impacts caused by irresponsible aggregate mining can compromise mining in an entire region.

Jan 1, 2001

By A. H. Sharbaugh

It is believed that considerable economic benefit would arise if run of mine (ROM) coal from the underground mines in the Winifrede seam could he enriched before shipment to the preparation plant by partial removal of the shale. Shale could comprise up to 50% of the ROM product. Complete mine-mouth separation is not necessary, but any process must be dry and have high Btu recovery. We have conducted a preliminary analysis of coal/shale mixtures from the Winifrede seam and we find that it is quite possible that a 50-50 ROM mixture of coal and shale could be converted to a 60-40 coal-shale mixture by inspection of individual lumps coming from the mine. The device would consist of a feeder/siever section to deliver the ROM coal > 5 cm (2 in) to an inspection station via a conveyor belt. This inspection station decides if a piece is coal or shale, and if it is shale, activates an air jet to blow shale off of the belt. We have evaluated a dielectric loss technique for the inspection device. The potential advantages of the dielectric loss method are high throughput, low capital cost, and no special handling or licenses would be required. Such a single lump inspection technique is made possible because of advances in high speed electronics and servo systems. This paper provides a summary of our analyses on the Winifrede coal sample, a description of a proposed apparatus to separate coal from shale, some of the experiments needed to demonstrate our ideas.

Jan 1, 1984

By S. Que

Local community acceptance is a key aspect of planning and managing mining projects, whether through sustainability assessment and reporting or corporate social responsibility programs. However, there has been very little research to understand the determinants of community acceptance. This paper seeks to identify key mine characteristics and demographic factors that influence individual acceptance of mining projects. Six demographic factors and 16 mine characteristics were selected based on literature review. Four of the six demographics factors were confirmed to be significantly (p < 0.05) correlated with people?s attitude of the importance of the mine characteristics. All sixteen mine characteristics are identified as important factors. The most important mining factors are Job opportunities, water shortage or pollution, air pollution and land pollution. Both the mining and control groups have same opinion of 12 mining characteristics and differ on four (infrastructure improvement, labor shortage for other businesses, noise pollution, and mine life). During design and management of mines, this data can be used as a reference. This result will facilitate better choice experiment (survey) design for discrete choice modeling. Such discrete choice models can provide a viable framework for data-driven community engagement and sustainable mine management.

Feb 23, 2014

By R. K. Singhal

A variety of mining equipment is used in the mining of oil sands by surface mining. This includes bucket wheel excavators, draglines, hydraulic shovels and off-highway trucks. This paper examines the existing mining schemes and equipment used Peculiarities of oil sands surface mining and their influence on equipment selection, utilization and mining schemes are described. Recent developments undertaken to improve mine productivity are also dealt with together with some notes on proposed measures to obtain further gains in productivity.

Jan 1, 1985

By Jian Liu

The dissolubility of a natural sphalerite (ZnS) in the entire pH range was theoretically calculated, and its practical dissolution in an aqueous solution at different pH values in an inert environment, together with its surface properties after dissolution, was fully investigated. The results of the investigation indicate that the total concentration of Zn (CZnT) decreases significantly with the increase of pH value, while the pH value is set below 8; however, it reverses when the pH value reaches 8. Such a tendency is similar to that of the theoretical calculations, although the experimental CZnT were much higher than those of the theoretical calculations. The X-ray photoelectron spectroscopy (XPS) of the sphalerite surface after its dissolution under alkaline solution shows that a polysulfide (Sn 2-) surface layer with a binding energy (BE) value of 162.96-163.25 eV is present on the surface, and the percentage of Sn 2- increases significantly with an increase in pH value; the undissolved and dissolved sphalerites under the acidic solution have a negligible difference in S2p peaks. The surface S/Zn ratio of all dissolved sphalerites shows a marked Zn enrichment and S deficiency. An atomic force microscope (AFM) view of the sphalerite surface, after its dissolution under the alkaline solution at a pH of 12, shows that the surface is significantly different in morphology from that of the undissolved one.

May 1, 2012

Conditional simulation provides a model of the ore body that represents variability in the data. This can be used to determine the impact of various grade control and mining strategies. A number of transfer functions are discussed that assist in optimizing grade control sampling. The cost effectiveness of various drilling and trenching techniques are discussed. Modelling of the expected performance of a mill head grade sampler is investigated. Conclusions are drawn about the likely impact of various sampling techniques on the economic performance of an operation and about applying sampling theory to grade control sampling.

Jan 1, 1999

By A. K. Snelgrove

At a time when water resource planning is proceeding on a continental scale, such as the proposed $100 billion North American Water and Power Alliance, which would redistribute water among three nations, including seven provinces of Canada, 35 of the United States, and three States of Mexico, the selection of a single river basin for study may seem to require an apologia. None is offered because of ( 1) the magnitude of the Indus , itself a part of the great Indo-Gangetic Plain drainage system, with Himalayan sources, upon which the thickly populated northern sub-continent of Indo-Pakistan depends for agriculture and hydroelectic power; (2) the extraordinary problems created by dismemberment of the world?s largest irrigation system through legal beheading of the Eastern Waters under the Indus Waters Treaty of 1960; and (3) the herculean effort to contain the twin encroachments of waterlogging and salinization in a basin which faces a shortage of fresh water. The British irrigation system of barrages and canals on the Indus was a venture admirable in conception. Unfortunately, it is now a legacy burdened with unwanted consequences, due to interference with the hydrological regimen, particularly the rise of water table occasioned by leakage.

Jan 1, 1967

By C. Patrick

Longwall face-to-face transfers can cost over $100 per minute in lost production potential and $100,000 for personnel and supplies. Such high cost makes extensive planning and control of the transfer process a critical necessity for the economic feasibility of longwall operations. This paper reports operations research techniques used for the analysis and modeling of longwall face-to-face transfers. Transfer data has been collected from companies who operate over 30% of the total U.S. longwall faces. Comprehensive sequence networks of existing longwall transfers were developed; simulation models of transfers under varying conditions were generated; and, the economics of general transfers and time-cost tradeoffs in the transfer procedure were investigated.

Jan 1, 1993

By S. P. Winkelmann

The expansion in gold production in the Carlin &apos;Trend over the last few years has been one of staggering proportion. To increase gold production while minimizing capital requirements and providing for the safe and efficient mining and processing of ores has required a tremendous effort by the Mine Engineering group at Newmont Gold. This paper discusses the organizational changes implemented to effectively deal with a full range of engineering problems and how the Newmont Gold Mine Engineering group dealt with these problems. Specially developed computer software and their applications will be explained. Improvements in the techniques used in converting geologic resources into reserves, and in scheduling the mining of multiple pits to feed multiple processing facilities, as well as ore control procedures are presented. Current mine engineering practices are discussed.

Jan 1, 1990

By H. M. Brennecke

A new hydrometallurgical process has been developed to recover copper from sulfide ores. Copper is leached in a staged reactor system utilizing nitric and sulfuric acids at 105°C. Iron is removed from the pregnant liquor as a jarosite and cathode copper is electrowon directly from the purified pregnant liquor. The spent electrolyte is recycled. Nitrogen oxides evolved from the leach are reconverted to nitric acid and are also recycled. Sulfur is rejected as S°, jarosite and gypsum. The process is highly versatile and can recover precious metals, molybdenum and zinc, when these elements are present. Continuous, integrated, semi-pilot plant operations using chalcopyrite ores demonstrated 99% copper leaching and production of cathode grade copper. Economic evaluation shows that the process is competitive with pyrometallurgical and other hydrometallurgical processes.

Jan 1, 1978

By John F. Burst

For several generations now, the high alumina clayey sediments of Southeastern Alabama and Southwestern Georgia have supplied those regions with steady, mineral-based income although the impact of that income has been relatively minor until recently. Since World War II, mining activity has increased algebraically with over half of the total ore value in the Alabama area having been recovered since that time. The Georgia area production increases are even more dramatic. The trends are continuing and the next decade should see ore winning figures which will dwarf all previous production. It&apos;s time for the mining engineers to take note of this development as the mining methods, similar to the production, have developed rapidly and now offer challenges for the most competent professional. The development of mining techniques has followed a classic pattern. Beginning almost a hundred years or so ago, with the loading of weather-resistant surface boulders into mule-drawn wagons, mining methods have progressed to discovery of limited surface exposures in outcrop and eventually to stripping and development of non-obvious, subsurface deposits. Little by little, the overburden thickness of new pits has increased until, at present, pits with 100&apos; -125&apos; of overburden are being actively worked. Ground water problems in the Eufaula District are particularly challenging. At A. P. Green&apos;s J. W. Baker Pit, #l, in Barbour Co., Alabama, it is necessary to continually pump groundwater at the rate of about 400 gallons per minute from wells on the periphery of this large pit in order to keep the water table low enough to allow mining of the ore body.

Jan 1, 1972

By Brad Simser

Several case histories from Glencore’s Sudbury Operations show how passive seismic monitoring data is used for geotechnical decision making. The data comes from three different seismic arrays monitoring two open stoping deposits, and a narrow vein cut and fill/blasthole operation. Mining depths range between 1000 to 1680m below surface. The deposits are hosted in hard igneous rocks typical of the Sudbury basin, with characteristically high horizontal stress (approximately 1.8 times the depth of overburden). Rockbursting is the main geotechnical risk, due to the strong brittle nature of the rock and local high mining extraction. Fault related seismicity includes both fault slip events, and the stress channelling effect as the mining front approaches a major fault structure. Planar data trends generally line up with known faults and often indicate early stage fault activation. The structures are risk ranked based on their seismic response. This has been particularly useful at the Nickel Rim South Mine (NRS) where the structural fabric (jointing and small-scale faulting) is generally parallel to the more through going faults. The persistence of structures is difficult to measure, and the NRS faults generally have low offsets and thin gouge. The visual difference between the more persistent structures that occasionally generate large seismic events (up Mw 2.9 to date) and localised joints/slips is often minor. The seismic monitoring data clearly shows the more active structures. This information is highlighted on mine plans to help guide enhanced ground support and seismic re-entry protocol barricade locations. Pillar loading/yielding is a key element to the blasthole operations where a primary/secondary mining sequence is used. The secondary pillars are mined in a yielded state with just-in-time development. An example of the seismic signature of a secondary stope is shown with emphasis on the need for high location accuracy given the stope widths of 12.5 to 15m. The ratio of the shear wave energy to primary wave energy (Es/Ep) has long been used as a method to estimate source mechanisms; the higher the ratio, the more likely the event is fault slip versus rock fracturing. Data sets are filtered on Es/Ep ratios to highlight both fault slip populations and stress fracturing mechanisms. Examples of seismic data quality checks, high stress development, and re-entry protocols are also shown in the case histories.

Apr 26, 2022

By David Mast, Amanda Foote, Mina Shinouda

The Michigan DOT’s I‑75 Modernization Project, Segment 3, is a 30-year, $1.2 Billion design-build-finance-maintain project in Southeast Michigan. The scope includes building a nearly 4-mile long, 14.5-foot ID stormwater storage tunnel. The tunnel and pump station are being built concurrent with new roads and bridges, requiring multiple levels of design and construction coordination. Underground risks include the poten‑ tial for encountering granular soils, groundwater, and explosive gases. The new tunnel will be mined by a new open-face TBM and lined with a one-pass steel-fiber-reinforced precast concrete segmental lining. Shaft construction began in early 2020 and tunnel mining in July 2020.

Jun 13, 2021

By Charles Kocsis, Pedro Nascimento, W. Patrick Arnott, Samuel J. Taylor

Respirable crystalline silica (RCS) is an inhalation health hazard for mining and industrial work environments and must be monitored. We provide theoretical analysis of real-time measurements for determining RCS mass concentration without the use of filters by using photoacoustic spectroscopy. The suspended dust in the mine air can be continuously sampled by the photoacoustic instrument. A tunable quantum cascade laser is the light source, allowing for determination of interferences such as kaolinite, coal dust, and water vapor. The most useful spectral region is found to be between 11 and 13 μm. Absorption by water vapor, and, to a lesser extent, carbon dioxide, in this spectral region has gaps that allow for quantification of the aforementioned dust species as well as a convenient check on the calibration of the instrument. This work brings photoacoustic measurement of aerosol to the mid infrared range where spectrally dependent light absorption can be used to quantify dust composition and mass concentration.

Jul 31, 2022

By Ji Fang, Chong Fan, Fengrui Wang, Dongxin Bai

Unmanned mining technology in underground mines offers high efficiency, safety, and low cost. However, ground operators face challenges in accurately perceiving the underground environment through videos. This paper presents an augmented reality (AR) platform developed to enhance the unmanned mining process. The platform uses cameras and 5G technology to transmit high-fidelity video streams to the ground, where key targets are identified and virtual models are registered in the video to enhance the real scene. Tests in the Xinli stope of the Sanshandao gold mine showed the platform’s effectiveness in improving ground operators’ perception and production efficiency.

Jan 30, 2022

By Meghan Murphy, Yiming Sun, Kush Chohan

DTX is a 1.3-mile-long rail extension being constructed by Transbay Joint Powers Authority to extend Caltrain rail service and future California High Speed Rail service to downtown San Francisco. It includes a 3,352-foot-long mined tunnel with a cross section varying from 50 to 60 feet wide and 43 feet high to accommodate two- and three-rail tracks. DTX will be excavated in mixed-face and Franciscan Formation with ground cover ranging from 40 to 85 feet. This paper discusses how mined tunnel design has evolved since the initial preliminary design phase over 10 years ago. The current design concept for tunnel construction is also discussed.

Jun 13, 2023

A knowledge of airway friction factor (K-factor) is necessary to designing mine ventilation systems for least cost and optimum effectiveness. The friction factor used must be accurate and reliable to estimate correctly roadway resistances and pressure sources for required flows. Though the resistance to flow offered by mine airways has been an object of study over the last half century, no accurate relation has yet been established from which the prediction of the resistance of a projected airway can be made. In Kentucky, only limited and incomplete data on local K-factors are available. Therefore, there is a need for field investigations to determine these values in-situ for existing mining conditions. The author describes a study concerning K-factor that was carried out in ten coal mines, located in eastern and western Kentucky. The results of these investigations are presented in both tabular and graphical form.

Jan 1, 1991

By I. A. Tinto

Labrador City is located in the southwestern portion of Newfoundland-Labrador, approximately 965 kilometers north-east of Montreal. The mine and beneficiation complex of the Iron Ore Company of Canada, known as the Carol Project, is situated 535 metres above sea level in a climatic region characterized by cold winters and short, cool summers. History The iron Ore Company of Canada commenced work in the area in 1949, however, it was not until 1958 that the decision was made to proceed with mining operations. The ore body consists of Specular Hematite (Fe203) and Magnetite (Fe304) with small quantities of Limonite and Geothite. The average grade of the ore bodies is 39% iron.

Jan 1, 1985