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By A. ALLANORE, OLIVEIRA M. DE, D. CICERI, D. P. CHEN

The alkaline hydrothermal processing of K-feldspar rocks in an autoclave can be a pathway to synthesize a potassium fertilizer for tropical soils that is potentially cheaper and more efficient than traditional potash (KCl). When K-feldspar undergoes hydrothermal alteration in the presence of calcium oxide (CaO), it generates a complex mixture of calcium-aluminum-silicate-hydrate (CASH) minerals that incorporate K atoms stochastically in their structure. These atoms are subsequently released, as shown in a test-tube leaching test, indicating a possible uptake by crops. The relationship between the processing temperature and time in the autoclave for the hydrothermal reaction and the resulting mineralogy and elemental release are only partially understood and are investigated in this study. Elucidating that relationship is the key requisite for subsequent techno-economic analysis, and ultimately for the development of a fertilizer that can be considered as a feasible alternative to KCl.

By M. Dayne Aldridge

A discussion of the definition of automation in mine ventilation applications is presented. The results of theoretical studies, experiments and practical experience from work in the United Kingdom, Belgium, Poland, the Soviet Union and the United States are summarized. Conclusions are drawn from these efforts and the prospects for the future development of automatic mine ventilation systems are explored.

Jan 1, 1978

By W. Gibson Jaworek

It has become apparent in recent years to everyone intimately concerned with the future of the American fuels industries that the growth in demand for energy has become a topic receiving considerable attention, and that investigators are leaning more and more toward a mathematical approach to deduce what pattern that growth will follow. Though coal has been included by necessity In all-studies of future energy markets, it has not been the subject of mathematical analysis or description as frequently as has been total energy or some of the other fuels, particularly petroleum, It is the intent in this particular paper, to subject bituminous coal consumption to a preliminary mathematical scrutiny which can lead to a more logical estimation of the general level of bituminous coal consumption for the next decade, as well as formulating an approach toward describing how coal consumption may vary as the result of the annual variations in activity in the United States, economy, The approach utilized is more sophisticated than the mere projection of the historical trend of bituminous coal consumption. Such a projection would lead to a continuation of the recent decline, indicating that coal consumption would reach zero some thirty years from now. On the other hand, the mathematical analysis described here is a relatively simple, straightforward approach and- is not intended to represent the-ultimate in mathematical economic analysis as now practiced, It is hoped that this will contribute to our knowledge of bituminous coal markets. Even more, it is hoped that it will help arouse a greater interestin utilizing mathematical and statistical analysis when studying the bituminous coal industry. - Since this is a preliminary study, comments and criticisms are anticipated.

Jan 1, 1960

By N. Iverson, E. Haft, V. T. McLemore, M. Woodard, E. Owen

Present and emerging technologies are renewing interest in domestic rare earth elements (REE) production. REE deposits throughout the North American Cordilleran alkaline-igneous belt are being re-examined for their economic potential. In New Mexico, the mineral deposits found in this belt are associated with Eocene–Oligocene alkaline to calc-alkaline igneous rocks. Four areas in New Mexico have been examined for their REE potential. The chondrite-normalized REE patterns are similar for all four districts, even though different REE minerals are found. Crandallite, xenotime, bastnäsite and brookite are found in fluorite veins and carbonatites at Laughlin Peak. Bastnäsite was extracted during fluorite processing from 1954-1980 from the Gallinas Mountains, where samples as high as 8% total REE are found in fluorite veins. Other REE minerals include agardite, parasite, xenotime, and monazite. Allanite, thorite and as much as 8133 ppm total REE are found in fluorite veins in the Capitan Mountains. In the Cornudas Mountains, exploration along the outer edge of the Wind Mountain nepheline syenite laccolith and within phonolite dikes, plugs, skarns and carbonate-replacement deposits in Chess Draw contain as much as 3110 ppm TREE, hosted in eudialyte, monazite, bastnäsite, and calciocatapleiite.

Feb 1, 2023

By Scott Ellenbecker

Mining has evolved in recent years, taking steps forward in the way that the industry is considerate of the environment and the communities in which it operates. Technology plays a major role in that evolution. Osisko Mining?s Osisko Mine near Malartic, Quebec is developing a new way of doing business. One manager said, ?We are building the Osisko culture,? but the company is doing many things that could become industry changers. Much of the change is driven by mine ownership and management to offer a better workplace and better community relations. Mining equipment manufacturers are changing, too, by engineering products with more operator comfort, fuel economy, ease of maintenance and more cleanly designed machines. And for those drills working close to communities, smaller bore sizes and sound retention are just two changes for the better.

Jan 1, 2012

By Ali Kazmi, Wern-ping N. Chen

A load rating procedure was performed to evaluate safe load capacity of the Port of Miami Tunnel (POMT), FDOT Tunnel No. 871071 SR 887. The rating procedure performed on a total of eleven stations beneath roadways and with fill depth less than the tunnel exterior diameter (42 ft). Calculations on tunnel sections passing beneath roadways were performed to evaluate the structural response of the sections subject to moving vehicular loads, dead load, and earth pressures. Ratings were performed in accordance with AASHTO and FDOT guidelines. The procedure considered two types of vehicles (HL-93 and FL-120) and two rating levels (Design level and Permit level). As part of HL-93 vehicle, Tandem load was also considered for rating, separately. For HL-93 and HL-93 Tandem, inventory and operating level ratings were performed. The results show rating factors are high. The minimum rating factor is 16.8 using Inventory truck HL-93. For Permit level using FDOT FL-120 truck the minimum rating factor is 6.9. As can be seen, rating factors are higher than comparable analysis for bridges. This paper explains how the procedure can be implemented for tunnels and evaluates the rating results.

Dec 1, 2022

By A. M. Radigan, W. G. Prast

M.S. Azun The authors' paper did not explain the facts and reasons why state companies are established and what their role is in international industrial mineral trading. Also, I do not agree with the conclusion implying that the main goal for state companies is to capitilize natural resources. Almost all state companies are founded by certain laws and their activities are arranged by state regulations. Their only aim is to operate mineral deposits for their people and to protect the rights of the people. Although some ore deposits, such as nonstrategic or small, may be exploited by privately owned companies, the state has the right to control the operation and production. Activities of state companies may or may not be widened because of the character of the deposits and the importance of the mineral market involved. For some countries, although governments may occasionally change hands, the policy of the mineral trading system is not affected by this change. There is no doubt that any government desires to make more earnings to increase GNP, when it is involved in operating and trading mines. It wants to produce and sell the finished products, instead of unprocessed ones, if possible. When it is known that some mineral deposits are relatively rare, such as Turkish boron deposits, the government can nationalize the mines to control production and affect the market. If there is an abundance of a certain mineral in the market, the government can cut production and set a floor price, such as Canadian potash. Also, when production of a specific mineral is unique, such as Turkish chromite, the price of such mineral may be set by correspondant government. One may add that if some governments with their state companies produce a certain mineral in a larger amount, they may decide to establish a cartel to protect their production and price. These are the facts followed by government-owned state companies and partially government-owned companies. The reason being charge of many deposits by the state companies is always the same: "protect" the mineral rights of the people.

Jan 2, 1984

By M. J. Allan, D. J. Barratt

This paper reviews current testing methods for sizing autogenom and semiautogenom mills in the North American context with comments on the necessity for test work and requirements for different circuits and equipment selection. The economics of testing and the value received are discussed.

Jan 1, 1987

By Wayne A. Van Voast

Many coal beds that will be mined in southeastern Montana are aquifers that provide essential local water supplies. Mine cuts along aquifer outcrops create almost imperceptible piezometric changes. Monitoring near such operations at Colstrip has detected almost no water-level declines in observation wells. Mine cuts between outcrops induce rapid storage depletion and associated piezometric depressions. One such cut near Decker induced 1,250 m3/day of flow from storage and created a piezometric depression of 3 meters or more as far as 1,500 meters from the mine. No wells have yet become non-productive but losses of some are inevitable as operations expand. Alternative supplies are available from aquifers stratigraphically below the disturbed materials. Effluents from active mines are chemically similar to other area waters because they are mixtures or ground waters entering the mine cuts. Occasional high concentrations of nitrate do occur, however, as residuals from explosives. Spoils generally consist of confined aquifers of wasted coal and coarse rubble at their bases, overlain by finer-grained sand, silt, and clay. Hydraulic conductivities and storage coefficients are comparable with those of undisturbed confined aquifers. Water quality in mined lands is highly diverse because of diverse spoils lithologies and poorly-established ground-water circulation. Ground water in spoils is more mineralized than in the coal beds and chemically resembles waters from sandstone aquifers. Hydrologic effects of mining will not be catastrophic or widespread but may have local significance. Most notable changes will be in water quality; availability will not be permanently reduced.

Jan 1, 1978

By Jack M. Campbell

The regulatory process by which governmental authorities acknowledge and, in turn, permit the location, construction, and operation of large scale energy-related facilities has become extremely detailed in recent years. One example of the detail that is entailed in the regulatory process is the number of permits that must be acquired by operators prior to the construction and operation of energy-related facilities. It has been estimated, for example, that 75 permits are required prior to the opening of a new coal mine in Pennsylvania while 50 are required in Kentucky. From the perspective of facility owners and operators the regulatory process often appears overly complex and may be perceived as a constraint to the corporate decision making process. From the perspective of those responsible for administering regulations, the process is perceived as a mans by which public desires - pursuant to social objectives such as environmental protection and occupational safety - can be achieved. As a result of conflicting organizational interests, the clash between energy facility owners and operators and their regulators appears to be inevitable. Furthermore, the resolution of this conflict lies in the tradeoff between objectives and the costs of regulation. The balance of objectives and costs is a subject of the political process and not a topic of consideration in this paper. This paper is concerned with the actual administration of regulations, that is, the implementation of that which arises from the interplay of organizational interests. The paper assumes that environmental control laws will not likely be repealed, that regulations to implement the intent of these laws are here to stay and thus the paper seeks to assess how regulations are administered at various levels of government pursuant to objectives. The paper hypothesizes that the administration of objectives (or policy) has an impact on decision making which affects energy facility decision; making while recognizing the fact that regulatory policy cannot be totally divorced from administration, this paper proceeds

Jan 1, 1977

By G. W. Heunisch

G.A. Carmody and L.B. Anderson We wish to comment on the paper by G.W. Heunisch (MINING ENGINEERING, January 1987), which raised several important points regarding treatment of acidic waste waters. This paper confirms, in part, tests carried out by Allyn Corp. Allyn is the manufacturer of the proprietary product Alka-Ment, one of the materials that Heunisch tested. The first point is the extreme sensitivity of the sedimentation rate on the nature of the treatment material used. This apparently results from differences in nucleation of the metal hydroxides, and is consistently higher for Alka-Ment. This decreased sludge volume is also observed when Alka-Ment is combined with flocculants, such as organic polymers (see Table 1). Our second point is to emphasize that Heunisch's work shows how dependent the sludge volume is on pH. It is common practice to overtreat AMD by raising pH to 9 or 10. This practice, in addition to being wasteful of material, actually decreases the density of the resulting sludge, probably by creating charged particles that do not readily coalesce. When treating with Alka-Ment, we recommend that the treatment be monitored by testing both pH and dissolved iron. For both tests, it is important to allow adequate time to elapse between treatment and measurement, so that dissolution of alkali, aerobic oxidation of iron, and precipitation of the metal hydroxides are nearly complete. Our tests have indicated that from 30 minutes to one hour is commonly required. Only in this way can a minimum pH be attained, with adequate treatment, denser sludge, and lower treatment rates achieved. Thirdly, Heunisch correctly recognizes that ASTM titration of Alka-Ment does not reflect the true treatment value available in a unit of Alka-Ment. Our work at Allyn indicates this is a most important consideration when evaluating various materials for the treatment of acidic waste waters. While we were unaware of Mr. Heunisch's work, we welcome comparisons between Alka-Ment and any competitive products readily available for field use. Allyn has hundreds of hours of laboratory and field data we are ready to share with interested parties treating acidic waste water.

Jan 9, 1987

By S. R. Dismukes

Mining is likely to be targeted by The United States Environmental Protection Agency (“EPA”) as one of its key enforcement targets for fiscal year 2002-2003. Identifying the mining industry as an enforcement target, coupled with an increase in enforcement activity in recent years, places each mining operation at increased risk of receiving enforcement attention. A properly developed and implemented Environmental Management System (“EMS”) tailored for your operation is invaluable in reducing the risk of incurring liability for non-compliance. At the heart of an effective EMS is an audit program that checks the company’s compliance with environmental requirements. In addition, audit privilege (in select states), voluntary self-disclosure, and the attorney-client privilege serve as very effective tools for managing those liabilities that may arise during auditing a well-developed program. Of course, these latter tools are effective only if the auditing program is properly structured and properly managed. EPA and some states also provide varying degrees of immunity for environmental violations that are voluntarily disclosed in writing by the company. However, self-disclosure laws and policies typically prescribe stringent requirements for parties seeking to take advantage of them. For example: U.S. EPA has recently extended the time period in which to provide full written self-disclosure to 21 days. However, U.S. EPA’s revised Self-Disclosure guidance also addresses when a company obtains knowledge of a violation for purposes of triggering the 21-day clock and specifically extends the knowledge requirement to include the company’s agents and consultants. This expansion increases the difficulty companies may have in clearly defining and managing when they obtained knowledge. This difficulty increases the importance of managing factual development and the strategic use of other

Jan 1, 2001

Mine design and selection of ore processing capacity depend upon a correct estimate of the grade-tonnage distribution. The estimate must reflect what can be recovered and processed. The McCoy/Cove operation in central Nevada, USA, is a gold and silver mine. Case studies of recoverable reserve estimation for gold and silver were made using multiple indicator kriging and the log-affine variance correction. From this model, the grade-tonnage distribution was constructed. Optimal pits were generated by utilizing the distribution, and the results were compared with the pit generated by ordinary kriging. Studies indicate that the proposed method for multi-metal recoverable reserve estimation is more accurate than ordinary kriging in terms of both tons and the grade. Using recoverable reserves for mine design will maximize global recovery of mineral resources.

Jan 1, 1997

By A. Janwong

Ion exchange technology is becoming more prevalent for metal recovery from low concentration solutions. The products of ion exchange are typically a metal free stream (product stream) and a concentrated metal stream (byproduct). The metals in the concentrate stream are usually precipitated and returned to the process or discarded. The unique features of emew® technology enable metals to be recovered directly from the concentrated stream. The advantage of the IX-emew® combination is the ability to have two product streams: 1) clean metal free solution and 2) metal product for sale. In addition to recovering metals from solution, it is also possible to separate metals from each other and recover more than one metal product. In this paper, examples of IX-emew® combinations are detailed including the recovery of copper, nickel and cobalt from an industrial waste stream, recovery of nickel from a spent electroless nickel plating solution and recovery of cobalt from an hydroxide cake.

Feb 23, 2014

By G. A. Johnson

Basic management principles will be discussed (as they apply to minerals education efforts), especially in light of the changing nature of volunteerism in today’s society. Also, the “minerals education tree” will be presented, along with public opinion / public policy realities.

Jan 1, 2001

By I. Mazalov, G. Ospanova

Introduction Today, uranium is of great interest because of its application to nuclear power and nuclear weapons. Kazakhstan has been an important source of uranium for more than fifty years. All uranium products are exported. Results In Kazakhstan uranium exploration started in 1948 and developed in several parts of the country thru mining of hard rock deposits. There are known around 50 uranium deposits in six provinces: Shu-Sarysuyskaya (57%), North Kazakhstan (18%), Syrdaryinskaya (15%), Ilyiskaya (7%), Caspian (2%), Balkhash (1%). In the Northern Kazakhstan province, KazSabton took over Tselinny Mining & Chemical Co in 1999. In this province the stockwork is of Paleozoic and Paleozoic folded complexes origin. In the Balkash province some mining of volcanogenic deposits occurred during the Soviet era. This province’s stockwork is of Endogenous origin.In the Ili province uraniumis mainly found in uranium-coal deposits formed by oxidation of the lignite beds roofs. In the Caspian province the Prikaspisky Combine operated since the 1960s a major mining and processing complex on the Mangyshalk Peninsula. This led to the founding of Aktau. It was privatised as Kaskor in 1992 and operations ceased in 1994. The uranium occurrence is associated with the phosphorous from fossil fish bone detritus conglomeration. In the Chu-Sarysu province, which has more than half the country's known resources, both Stepnoye and Tsentralnoye have been operating since 1978 and 1982 respectively. Uranium mineralization occurred in the regional stratum oxidation zones. In the Syrdarya province slightly to the west of the province’s center the No.6 Mining group has been operating since 1985. Uranium mineralization occurred in the regional stratum oxidation zones.

Jan 1, 2007

By John A. Cherry

Groundwater monitoring conducted at an acidic uranium-tailings impoundment in Wyoming and at one in Ontario indicate that at these unlined impoundments situated on unconfined sand aquifers, there exist well-developed plumes of contaminated groundwater. In the literature similar results are reported for three other unconfined aquifers at mill sites in Wyoming. The plumes extend for distances of several hundred to a few thousand metres from the impoundments. They have a zone of low pH beneath and adjacent to the impoundments and a larger zone of near-neutral pH that extends to the outer limits of the plume. The low-pH zones are generally small compared to the neutral-pH zones because the advance rate of the fronts of acidic tailings-derived water is slower than the average velocity of groundwater which controls the advance of the high pH zone. The retardation of the acid fronts is a result of geochemical reactions that cause hydrogen-ion consumption in a slowly-advancing neutralization zone. Within each of the plumes, the low-pH zone has high concentrations of transition metals, heavy metals and radionuclides. In the neutral-pH zones all of the metals and radionuclides occur at significantly lower concentrations and are generally at levels much below those specified in national drinking water standards. An exception at two of the Wyoming sites is uranium, which exists at levels close to the drinking water limit. A second exception is ferrous iron at the Ontario site, which occurs at high concentrations throughout most of the plume. The carbonate alkalinity at this site is much lower than at the Wyoming sites. The field data indicate that even in very permeable aquifers with a low content of silt and clay, there is normally a considerable capacity for acid-front retardation. To take advantage of this capacity to control contaminant movement in the design, operation and decommissioning of tailings impoundments, it is necessary to be able to predict the rate of acid-front movement. This predictive task has two primary components. The first is to identify the important flow paths from the tailings through the groundwater system and the second is to determine the degree of acid-front retardation that will occur as the tailings-derived water moves along these flow paths. Relative to these two tasks determination of the effects of hydrodynamic dispersion is generally of lesser importance and simple approximations that do not involve field or laboratory tests are probably adequate. In order to effectively apply the acid neutralization concept to the prediction of subsurface contaminant migration at uranium-mill tailings, improved representations of hydrogeochemical behavior of iron and aluminum in the neutralization zone and of the consumption of hydrogen ions through reactions with carbonate and aluminum-silicate minerals are required. Along with the hydrogen ions contained in the tailings water the ferrous iron represents a large potential source of acid but the extent to which ferrous iron converts to ferric iron to produce acid is problematic. Detailed hydrogeochemical evaluation of existing contaminant plumes and the performance of laboratory experiments under appropriate redox conditions ore prerequisites for the improvement of predictive models. However, the existing field and laboratory data provide a basis for preliminary predictions of contaminant migration from acidic uranium tailings impoundments.

Jan 1, 1982

By D. E. Hulse

"Social License, the consent of the neighbors and community to develop and operate a mine, has received little attention until recently. Though social license is intangible, not having this relationship with the community carries operational and economic risk to a project, potentially including future impairment of the asset. Acquiring and maintaining social license is a long term personal relationship. It requires communication, commitment, consistency, and transparency. This presentation will review the building blocks to acquire and maintain a social license based on experiences with mining projects in Mexico. INTRODUCTION Mining has been a source of controversy for at least 500 years. “Since there has always been the greatest disagreement amongst men concerning metals and mining, some praising, others utterly condemning them” (Agricola 1556). In 2015 it is widely recognized that mineral resources and reserves must give due regard to the social license in order to operate. “Most commonly, the SLO is understood to refer to ‘the ongoing acceptance and approval of a [project] by local community members and other stakeholders that can affect its profitability’ (Moffat 2014).” “Social License to Operate has gained traction, in part, because it is also a concept which – while remaining poorly, technically defined – is generally easily and widely understood by community stakeholders.” (Bice 2014) A generation ago I learned that mining is based on a stable platform supported by three pillars, geology, mining and metallurgy. The three legged stool is a very stable structure.In 2015 it seems that we have added some other legs to the stool. The JORC code addresses “social, and governmental factors” (JORC 2012), and refers specifically to social license in Section 4 of the Report Template “Estimation and Reporting of Ore Reserves”. The Canadian CIM Guidelines refer to “environmental, legal and social data” (CIM 2003).Compared to these the 2014 SME Guide is positively verbose stating “a discussion of any potential social or community related requirements and plans for the project and the status of any negotiations or agreements with local communities,” (SME 2014) although in all cases the scope of this disclosure is left at the discretion of the Competent Person."

Jan 1, 2016

By Devin Burns, Saima Ghazal, Michael Owusu-Tweneboah, Kwame Awuah-Offei

Trust in AI systems and the nature and amount of information about the system can influence decision-making. It is, therefore, crucial to understand how AI-powered monitoring systems (e.g., gas monitoring systems) influence miners’ trust and decision-making in emergency evacuation. This work focused on measuring the differences between how participants respond to a simulated underground mine emergency evacuation situation when warnings are represented as coming from a human or AI-based monitoring system. We also manipulated the amount of information participants received about the system, yielding a 2×2 between-participants survey design. The participants received an alert message about rising gas levels in a mine and provided a response on how they would react and reported their perceived safety. We also asked questions to assess their trust in, preference for AI over human-based gas monitoring systems, and whether they are willing to delegate the duties of underground gas monitoring to AI systems. The experiment results show the amount of information had a significant influence on miners’ trust and decision-making. The safety perception of participants based on age, number of children and ethnicity was significantly different from one category to another. This work provides valuable insights as the mining industry deploys AI systems to aid mine safety.

Feb 1, 2025

By Pafos Busch, Martin Fischer, Johannes Jaeger

The Spitzenberg Tunnel is a 600 m (1,970 ft) long twin tube motorway tunnel on Germany’s Autobahn A44 between Kassel and Eisenach. Since flexibility was considered to be very important in the continuously changing geological conditions, NATM was chosen as the construction method. When passing an old quarry with only 1,80 m (6 ft) of overburden, the excavation works became extraordinarily challenging. This paper not only describes the special methods, like double sidewall drifts and pipe umbrellas applied in this zone but also highlights the cooperation between the parties involved, which in combination made the project a joint success.

Jun 13, 2021