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By S. M. Pickering, L. T. Gregg

Appraisal of industrial minerals beneath privately owned land requires a different approach and mindset from valuation of base and precious metals or energy minerals, and from valuation of government-owned mineral lands. First, is it the value of inground minerals or of mining rights that is being sought? Second, value to whom, the mining company, a potential investor, the mineral landowner, a lending institution, the property tax assessor, or a condemnor? Third, how should mineral value be apportioned between the land and mineral owner, and a mining company with limited years of lease-hold interest? These and many other questions must be addressed before a valuation method and Discount Rate are selected. For various reasons the Income Method is most often used, with Net Present Value calculations made for long term predicted mining income. Choice of an appropriate Discount Rate is critical.

Jan 1, 2000

In 2006, a total of 7,178 sand and gravel mining operations reported employment to the Mine Safety and Health Administration (MSHA).1 ? Sand and gravel mines were the largest mining sector, comprising 48.2% of all mining operations. ? Sand and gravel mines were found throughout all 50 states and Puerto Rico.

Sep 1, 2008

By R. C. Freas

Composite materials are finding new applications daily, ranging from automotive parts to synthetic lumber. The variety of applications seems almost limitless. However, these emerging products bring both new opportunities and new challenges to the field of industrial minerals. One of the primary challenges is from alternative materials other than industrial minerals. Thus the question is asked whether industrial minerals will truly benefit from the growth in market applications for composite plastics. This article highlights some of the opportunities for industrial minerals while focusing on performance and competitive demands on mineral products intended for use in this developing market.

Jan 1, 2000

By Hisataka Sakakibara

Although the pathophysiology of vibration-induced white finger (VWF) is still under discussion, evidence has been accumulated to understand the underlying mechanism. VWF is pathophysiologically characterized by an enhanced vasospastic response to cold, which can result from an imbalance between vasoconstriction and vasodilation in the digital arteries in response to cold (i.e., vasoconstriction-dominant). The imbalance is supposed to be due to faults in vascular vessels and sympathetically mediated vascular tone. Enhanced vasospastic response to cold Narrowing of arterial lumen with medial smooth muscle hypertrophy. Possible functional factors for enhanced vasoconstriction • Increased sympathetic nervous activity to cold (e.g., norepinephrine) • Increased release of endothelin-1 (ET-1; an endothelial-dependent vasoconstrictor) from the endothelium • Increased reactivity of alpha2-adrenoreceptors to cold Possible functional factors for decreased vasodilation • Decreased release of nitric oxide (NO; an endothelial-dependent vasodilator) from the endothelium • Decreased release of calcitonin gene-related peptide (CGRP; a vasodilatory neuropeptide) from sensory afferents The question is how their interrelations or imbalances among them are Vibration and arterial damage The next question is, how does hand-arm vibration exposure induce such pathophysiological changes in VWF patients? Recent morphological evidence from animal experiments shows that vibration acceleration stress (including shear stress) and smooth muscle contraction contribute to arterial damage of smooth muscle and endothelial cells. The vibration-induced arterial damage is frequency-amplitude-dependent.

Jan 6, 2006

By E. Bauer, S. Moore

Technological advances in underground coal mining have led to a reduction in fatalities. This study demonstrated that the percentage of cumulative injuries remained largely unchanged across two decades of technological advances (1983-1984: 37%; 2003-2004: 33%). Furthermore, it was demonstrated that the average number of lost days due to cumulative injuries has increased (36±55 days and 62±82 days, respectively) which may have been due to the increased age of the work force or an increase in length of employment meaning that the mine workers injured in 2003-2004 had been exposed to ergonomic risk factors longer than those in 1983-1984. It is recommended that ergonomics processes be implemented as a means to systematically identify, prioritize, and resolve the root causes of these cumulative injuries.

Jan 1, 2007

By D. Harrington

Insofar as prevention of mine explosions is concerned, it is apparent that the coal-mining industry has profited but little from experiences during the past 15 years. The fact that explosions can be prevented if well-known preventive measures are adopted and conscientiously carried out appears to warrant the conclusion that many coal-mining people are indifferent to the hazards that may result in explosions. Although the principal burden of preventing explosions is upon the management, and much of the evident carelessness in failing to place in effect and to enforce suitable precautions, is assessable directly against management, the worker also has a very definite responsibility, and numerous explosions have resulted because of his failure to carry out his part in accepted principles of safety. The record of fatalities from mine explosions during the past 5 fiscal years has been anything but encouraging or about which coal-mining people can take pride; more men were killed by explosions (673) than were killed from the same cause during the preceding eight years combined (577). During each of the fiscal years 1942 and 1943, 152 fatalities resulted from explosions, compared to 163 during the fiscal year 1941, 206 in 1940, and only 16 in 1939.

Jan 1, 1944

By W. W. Odell

"It has long been recognized that coke is a more desirable fuel than bituminous coal in water-gas apparatus of present design, but still considerable headway has been made in the use of the latter fuel as a substiaute for coke. This is particularly true in the Central States where the supply of high-grade coke has been very limited and uncertain during the past few years, and where coking coals of low sulphur content were available in quan¬tities. In fact, with, the present difference in price of coal and coke, it is possible to realize a marked saving when using a coking bituminous coal as generator fuel.Difficulties have been encountered in the use of such fuel, but they have, to a large extent, been overcome. One of the chief obstacles in the use of the more general utilization of bituminous coal for water-gas manufacture, is the fact that, with normal operation, the capacity per unit of time is reduced. This of course is a serious problem for plants operat¬ing at capacity with coke fuel. However, this difficulty can, to a large extent, be remedied by a changed method of operating, and can be entirely remedied by a combination of the latter with a change in the design (or proportions) of a water-gas set. The preceding statement, the reader will understand, refers more particularly to a carburetted water-gas set.In the manufacture of water gas from coke, present practice requires that for continuous 24-hour service the heat of combustion of all the carbon monoxide (CO) generated during the air blow be utilized in addition to the sensible heat of the gas coming from the generator. This is doubly true when making carburetted water gas from bituminous coking coal. The reasons why this is so are apparent when the following factors are considered."

Nov 1, 1920

By J M. F Clout

Geological, textural and mineralogical classification of iron ores is routinely conducted by mine and exploration geologists on reverse circulation percussion, blasthole cone and bulk samples for grade control, defining ore and waste, determining lump:fines ratio and predicting downstream processing characteristics. Classification is based on physical hardness, colour, streak and other visual characteristics. However, logging is generally restricted to the five to 20 per cent of chips above about 2 mm. This means that most of the sample is too fine to be reliably logged for anything but colour or streak and the textural types must be inferred from other information. A recently developed software package called æRecognitionÆ allows automated identification and classification of iron ore textural types and gangue on a particle basis in polished section down to 0.01 mm using processed digital images. It is not designed to be used as a routine logging tool, but is applicable where higher definition is required at the resource evaluation stage on selected percussion, drill core or bulk samples. æRecognitionÆ processes data obtained after optical image analysis of fine iron ore samples. It contains several parts, like æRecognitionÆ, æCompositionÆ, æLiberation by Total IronÆ, æLiberation by PhasesÆ and æStatisticsÆ, which allow vast and diverse information to be obtained about the iron ore samples being studied. Identification and classification of the textural type of each particle is performed according to the CSIRO-Hamersley Iron Ore Group Classification Scheme. The recognition procedure encompasses a good knowledge of different ore types and a logical knowledge tree, managing fuzzy boundary problems and the potential for a few different ore types in the same particle to be considered. This new technology introduces strict criteria to make the process of identifying particles more objective. Automated recognition standardises the identification procedure and significantly saves time. It enables users without a strong background in mineralogy to perform accurate texture identification. The æRecognitionÆ package has a modern user-friendly interface and Word compatible output. The combination of all the features mentioned makes the package a convenient tool for detailed studies of fine iron ores.

Jan 1, 2005

By Earl Rau

Introduction Will cogeneration be a major power source in the future? The location of electric power generating plants has changed. In 1900, more than 50% of electricity was generated by industrial plants. Since then, industrial plant generation of electricity greatly decreased to 17% in 1950 and to only 3% in 1980. Changing economics in electric power generating costs, though, may allow cogeneration to reverse this trend. Cogeneration has been defined as the simultaneous production of electric (mechanical) and thermal energy from a single energy source. Some applications are considered to be byproduct generation of electricity from industrial, thermal operations. Cogeneration is not new to the mining and minerals industry. Smelters and steel mills have used waste heat to generate electricity. Public Utilities Regulatory Policies Act of 1978 The potential for increased industrial cogeneration of electricity is related to the March 9, 1978 enactment of the Public Utility Regulatory Policies Act (PURPA). The US Supreme Court ruled that PURPA is constitutional. The court upheld requirements that utilities interconnect to cogenerators. It also ruled that 100% of avoided costs be used as the guideline for electricity sales by a qualifying facility (QF) to a utility. The state of New York established a floor price $0.06/kWh for electricity sales from a QF to a utility. It is obvious, then, that a cogenerator must first establish price and then become a qualifying facility in order to sell electricity to a utility. Proposed cogeneration plants The estimated industrial cogeneration potential for the years 1986 to 2000 is 9500 to 25,000 MW. Industries represented in this cogeneration estimate are pulp and paper, petroleum, chemicals, food, textiles, rubber, plastics, steel, lumber and wood, cement, glass, metal fabrication, and industrial parks. A cogeneration plant has been proposed for the Union Carbide chemical plant in Institute, WV. A steam turbine/generator would be installed to replace the pressure-reducing valve in the 2.7 MPa (400 psig) header. Scott Paper Co., Mobile, AL, proposed a cogeneration plant using a coal- and wood-fired boiler and a turbine/generator to produce process steam and electric power. A cogeneration system has been proposed for a large oil refining plant. A pulverized coal boiler would produce high-pressure steam to operate a turbine, generator. The exhaust steam from the turbine will go to the process and an existing turbine. Kansas City, MO's Armour meat-processing plant has proposed a cogeneration plant. This proposal is to use a natural gas or oil-fired, gas-driven turbine and a generator. The waste heat from the gas turbine would go to a heat recovery boiler for use as process heat. Dade County, FL is implementing a central energy system to supply electricity, air conditioning, and domestic hot water for five buildings in downtown Miami. The cogeneration system is to provide flexibility, to optimize fuel use efficiency while serving the variable thermal demands. Generation of electricity from municipal waste is not considered to be a cogeneration process but is covered by PURPA. Special considerations are provided for waste/electric power generation to encourage the development of these systems. ?

Jan 7, 1987

By E. J. Matson

"The Bureau of Mines has been investigating deposits of critical and essential minerals in the United States since 1939. Projects were set up on only the most promising properties.A preliminary examination of the Mount Hope mine was made in January 1943 by the Bureau's engineers, who recommended exploration by diamond drilling.The mine is in the unsurveyed portion of T. 22 N., R. 1 E., Mount Diablo base and meridian, south-central Eureka County, Nevada, 25 miles by road north of the village of Eureka. A partly graded and Graveled secondary road connects the mine and Eureka on U. S. Highway 50.Extensive sampling was done by the Bureau in February. 1943. Core drilling from the surface was started on March 15, 1944, and completed on April 2, 1545. The 16 holes drilled totaled 7,215 feet. The mining company also did extensive underground core drilling from April 21, 1944, to January 4, 1945. This report gives the results of core drilling supervised by the Bureau of Mines.The drilling program was designed to explore for extensions of the mineralization exposed in the mine workings. As a result of drilling, additional ore was found, and it is believed that this project has fulfilled the purpose for which it was planned.In its program of exploration of mineral deposits, the Bureau of Mines has as its primary objective the more effective utilization, of our mineral resources to the end that they make the greatest possible contribution to na¬tional security and economy. It is the policy of the Bureau to publish the facts developed by each exploratory project as soon as practicable after its conclusion. The Mining Branch, Lowell B. Moon, chief, conducts preliminary examinations, performs the actual exploratory work, and prepares the final report. The Metallurgical Branch, R. G. Knickerbocker, chief, analyzes samples of ore and performs beneficiation test. Both these branches are under the supervision of Dr. R. S. Dean, assists director.With respect to this report special acknowledgment is due to Charles W. Merriam of the United States Geological Survey for his interpretation of the Mount Hope mine Geology and his cooperation throughout the project; Col. Leverett Davis, former lessee of the property; K. K. Hood, manager of the Mount Hope Unit, Callahan Zinc-Lead Co., Inc.; C. P. Knaebel, assistant manager, and M. P. Nackowski, geologist, of that company, for their help, and to the Sullivan Machinery Co. for its assistance."

Aug 1, 1946

West Virginia ranks second in the nation in coal production, surpassed only by Wyoming, and usually accounts for 15 to 20percent of the nation's total annual production. Cod occurs in seams of minable thickness in all but nine of the state's 55 counties. There are two coal- producing regions, the northern field and the southern field. West Virginia coal is mined by both underground and surface methods. Underground mines in West Virginia account for a major portion of its coal production. Surface mines are generally contour operations and, especially in the southern field, are in steep slope areas, with slopes greater than 20 degrees. Many of the surface mines remove multiple seams. Recoverable reserves in West Virginia total in excess of 55 billion tons of bituminous coal. West Virginia's regulatory program was conditionally approved on January 19, 198 1. Its Abandoned Mine Land Program was approved February 23,198 1, with emergency authority granted on August 26,1988.

Jan 1, 1992

By J Harris, J Turner, P Kirsch

Coal mining is recognised globally as a hazardous activity, and as a result operates under high levels of regulatory and public scrutiny while managing a workforce operating in a high-risk environment. Mining companies have developed sophisticated risk assessment procedures, management systems and personnel competency requirements that facilitate the safety and health of employees, and Australia is a world leader in coal mining safety and health.RISKGATE is an Australian Coal Association Research Program funded online platform that delivers broad cross-industry knowledge about current practice in the identification, assessment and management of coal mining risk. Centennial Coal has engaged with the RISKGATE program, managed by the University of Queensland’s Minerals Industry Safety and Health Centre, since its inception in 2010, and contributed topic experts to many modules, including underground topics within the geological and geotechnical domain (strata underground, outburst, coal bumps and bursts, and inrush).In 2013, Centennial Coal experienced significant unexpected strata failure at the Mandalong mine without any personal injury or fatality. This paper presents a case study in the application of RISKGATE to management of this unwanted event, the steps that were implemented, the information that was sourced and the contribution that RISKGATE made to the final outcomes. The Australian coal industry is encouraged to embrace our knowledge platform, and to also openly share processes and practical outcomes that result from integration of RISKGATE in mining operations.CITATION:Harris, J, Turner, J and Kirsch, P, 2014. Case study – application of RISKGATE to managing strata failure in an Australian coalmine, in Proceedings AusRock 2014: Third Australasian Ground Control in Mining Conference , pp 55–60 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 5, 2014

Optical sensors have emerged during the telecom boom in the late 1900s, due to the availability to low-cost telecom-grade optical components. It's only after the telecom industry's fall in 2004 that optical sensors became sufficiently developed to be a viable technology for real-world applications. Geotechnical applications have long relied on electrical sensors such as thermocouples, strain, and the venerable vibrating wire to measure physical phenomena. Although these are well suited for a large variety of applications, electrical sensors cannot be used for all applications: these are vulnerable to noise, hazardous voltages and corrosion, limiting the environments in which they can be used. In addition, electrical wires can also become an issue when sensors require external excitation or are distant from the measurement system. Finally, changes in physical properties of electrical sensors and systems over time makes regular calibration a necessity - not easy to do when these are permanently mounted on structures. Optical sensing systems are non-conducting and use light to perform various measurements. There are several optical sensor technologies available, each with different strengths and weaknesses. In addition, there are different methods of interrogating optical sensors, each of which also present different strengths and weaknesses. To make matters worse, configuring the interrogation and scaling to physical units can also be challenging to the unprepared engineer. This paper will present a holistic view of optical sensing, presenting the different optical sensor technologies and interrogation techniques. Sample optical sensing systems will be revealed and top considerations for optical sensing will be presented.

Nov 25, 2010

By Mike Adams

A comprehensive pre-feasibility study has been conducted by Companhia Vale do Rio Doce CVRD) for Niquel do Vermelho nickel laterite deposit. Within this study, five integrated flowsheet options were evaluated via batch and pilot campaigns at Lakefield Oretest, over an intensive six-month period from receipt of ore to final reporting. Key technical objectives set by the client included demonstrating the technical viability of the beneficiation of several ore types, processing through integrated pressure acid leach/mixed hydroxide precipitation (PALIMI-IP) and mixed sulfide precipitation (PALIMSP) circuits, and the treatment of barren liquors to meet stringent environmental requirements. Refining of the MHP was by ammonia re-leach and solvent extraction (SX) to produce LME-grade nickel cathodes, NiCO3, NiO and CoS. LME grade nickel and cobalt was also produced by oxidation of the MSP and hydrogen reduction on the leachate. The database and data acquisition system, along with web-based reporting, enabled rapid turnaround on both daily and more comprehensive run reports, making it possible for speedy and confident decisions on operating conditions of the complex flowsheets. The high value of developing such data is emphasized and discussed as pivotal in the successful progression of laterite projects through to sustainable commercial viability. Keywords: Flowsheet, CVRD, Nickel, Piloting, Pressure, Leach, Refining.

Jan 1, 2004

By J. J. Forbes

Since 1910 the Bureau of Mines has given training in the care and use of oxygen breathing apparatus under conditions that may exist during mine fires and after mine explosions. In 1929 the Bureau supplemented this instruction by initiating a course in advanced mine rescue training to prepare mine officials and others to organize men for mine rescue and recovery operations. The course of instruction has been developed and expanded since its inception to keep abreast with new ideas, methods, and equipment. Four miners' circulars were issued to be used in the training course. The first of this series (Miners' Circular 33) deals with mine gases and the various methods of detecting them; the second (Miners' Circular 34) gives instructions for sampling and analyzing mine atmospheres; the third (this circular) describes methods and equipment for protection against mine gases; and the fourth (Miners' Circular 36) explains procedures in sealing and unsealing mine fires and in conducting recovery operations, These circulars have been revised from time to time to keep them up to date.

Jan 1, 1954

By Allen W. Hatheway, John A. Albritton, Lloyd B. Underwood

Missouri River Division (FORD), U.S. Army Corps of Engineers (COE), has completed (October 1982) a study for the U.S. Air Force Ballistic Missile Office, in which desireable and needed changes in contracting methods for underground construction were identified. Due to the importance of geotechnical considerations in such construction, a good number of the resulting recommendations relate to geotechnical considerations. Corps contracts have traditionally served as models for contract documentation by public agencies and in private enterprise. Several standard features of present-day contracting methods were Corps innovations. Corps officials are generally in agreement with the recommendations of the Better Contracting reports published by the U.S. National Research Council (NAS/NRC), through its U.S. National Committee on Tunneling Technology (USNCTT). However, the findings of the 1982 MRD study indicate that additional changes are warranted for underground construction contracting methods; changes that deal specifically with site geological conditions, both known and to be reasonably anticipated, as well as with their associated impacts on construction. The 1982 MRD report identifies the need for nine specific improvements in geotechnical aspects of contracting; improvements based on recognition of geological conditions.

Jan 1, 1983

By Robert M. Becker

This investigation (in five parts) extends the theory of sample reliability from a sample consisting of a fixed number of items to a sample consisting of a fixed amount of items. Examples of a fixed amount of items per sample are samples consisting of a fixed weight or a fixed volume of unequal size particles. The extension of the theory is confirmed by experimental laboratory sampling using standard procedures. The probability distribution functions (the binomial, hypergeometric, multinomial, generalized hypergeometric, and those here called the compound binomial and compound multimomial functions) are developed from fundamentals. Their distributions are generalized to include some measured characteristic of the items. Infinite population moments are derived from moment-generating functions, and finite population moments are developed from corresponding infinite population moments using a newly defined mathematical operation. The first three experimental moments in laboratory sampling to given weights of particles are compared with the theoretical moments of their corresponding compound mult.inomial distributions. The agreement is striking. The study is divided into five parts. Part 1 deals with probability or random sampling to n items and with all sampling to n items per sample from some one probability distribution. This is the area of sampling covered by well-known theory. Accordingly, the procedures may be different but many of the results are well known.

Dec 1, 1964

By Ronald E. Heuer

A 1995 RETC paper of similar title presented a method for estimating rock tunnel water inflow based on semi-empirical correlations with borehole water pressure tests. Since that time the author has found the method to be very useful, and it has been used by others in the industry. This current paper is an update which is intended to: A. More clearly explain assumptions and limitations of the method. B. Describe some case history examples. C. Respond to questions which have been raised; and extend the method to other considerations including distribution of inflow along the tunnel, panning requirements, interpretation of tunnel probe hole water inflow, and estimation of potential effectiveness of pre-excavation grouting to reduce water inflow.

Jan 1, 2005

By R. W. Fedors, S. T. Green, F. T. Dodge, D. B. Walter

Spatial and temporal temperature variations in a high-level radioactive waste repository drift can give rise to moisture transport within the drift. Knowledge of this moisture transport may be important to assessing the potential for corrosion of all metallic components in the drift. The model presented here shows one approach to simulating evaporation, transport, and condensation of water in large underground openings using a framework based on computational fluid dynamics. Simulation results that explicitly model water and latent heat transport are presented.

Jan 1, 2004

By L. H. McGuire, L. B. Berger

"During the period October 31 to November 4, 1944, tests were conducted by the Bureau of Mines in the Cascade Tunnel of the Great Northern Railway Cc. to determine the effects upon the tunnel atmosphere of the use of a Diesel freight locomotive through the tunnel. These tests were conducted at the request of the company to ascertain whether undesirable conditions might be caused by the discharge of Diesel engine exhaust gas in the tunnel, which was constructed for an electric haulage system and is not provided with equipment for mechanical ventilation. The use of Diesel locomotives on the division that includes the Cascade Tunnel was under consideration as a means of augmenting haulage facilities for the abnormal freight tonnage that must be handled during wartime.As the Bureau of Mines has received requests for information on the extent of contamination of the air of railroad tunnels by Diesel locomotives, this report was prepared to make available for general information the data obtained during the tests in the Cascade Tunnel. As the test locomotive is of a type used on other railroads, and as the bore and grade of the tunnel and the tonnages moved are comparable to such factors on other roads, the data should be sufficiently representative to be of general interest. The exceptional length of the Cascade Tunnel made it an excellent location for obtaining information on the composition of the tunnel air and on the movement of air induced in the tunnel by the passage of trains.The writers are indebted to C. O. Jenks, vice president of the Great Northern Railway Co., who arranged for the tests, and to the following personnel of the railroad who cooperated in the conduct of the tests: I. E. Clary, superintendent, Spokane Division, J. L. Robson, superintendent of motive power, oil and gas equipment, J. F. N. Gaynor, superintendent of electric operations, William Lowney, master mechanic, Spokane Division, and D. F. Marston and Verne Nelson, assistant superintendents of electric operations.The Cascade Tunnel is on the Spokane Division of the Great Northern Railway and pierces the Cascade Mountains some 49 miles west of Wenatchee, Wash. The west end of this division is electrified from Appleyard Station, 2 miles east of Wenatchee, to Skykomish, Wash., a distance of 73 miles. Until the described tests, only electric haulage had been employed through the tunnel since it was first opened to traffic in January 1929.The Cascade is the longest railroad tunnel in the United States - 7.79 miles. The tunnel is single-track, perfectly straight, concrete-lined, and is on an essentially uniform grade of 1.56 percent, ascending from west to east. The cross-sectional area of the tunnel is 314 square feet, the dimensions being shown in figure 1. Elevation of the east portal is 2,880 feet and of the west portal, 2,240 feet."

Jun 1, 1946