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Some basic terms used in cost management and accounting include: - Cost. A sacrifice made to acquire goods or services, measured by the price paid. Technically, the sacrifice is called a cost until the benefits from the goods or services have expired, at which time the sacrifice is called an expense. In this text, the terms "cost" and "expense" are used interchangeably. - Revenue. An increase in the value of the firm resulting from the sales of goods and services. - Income. The excess of revenues over costs for a specified period. The term is often used with modifiers to indicate specific quantities on an income statement (e.g., pretax income; net income). - Activity. A measure of production work. Traditionally, physical production volume (tons of ore or units of product) has been used as the measure of activity. Other measures include direct labor hours, equipment operating hours, and quantity of materials or supplies consumed. - Responsibility center. A segment of an organization that is responsible for a specified set of activities. In mining, individual operating divisions can be treated as responsibility centers, known as profit or cost centers. Departments within a division are generally treated as cost centers. - Cost center. A portion of an organization having responsibility for achieving specified levels of cost. - Profit center. A portion of an organization having responsibility for achieving specified levels of profit (revenues and costs).

Jan 1, 1999

By L. K. Holder

The White King / Lucky Lass Superfund site consists of two former uranium mines in south-central Oregon. The remedy included consolidating two large mining overburden stockpiles that contained low levels of radioactivity and heavy metals by moving over 700,000 cubic yards of material and then capping the combined stockpile. An innovative armored cap design was used to minimize the stockpile footprint and thereby prevent disturbing existing wetlands. In addition, the stockpile was designed to merge into the surrounding topography. The remedy also included stream restoration and development of new wetlands. The stream was returned to its pre-mining channel, with the addition of hydraulic features to create new wetlands. The wetlands have greatly enhanced the ecological value of the remedy and the site.

Feb 23, 2014

By Andy Alder

The aim of this paper is to provide an overview and details of good practice, from a United Kingdom perspective, in the development and implementation of major tunnel and underground infrastructure projects. In doing so, it draws on a broad base of project management theory. A central theme is that successful project delivery is dependent on detailed planning of the complete project delivery process, forming an effective team that works well together and the proper management of risk. The role of partnering in forming a strong project coalition is described. Particular emphasis is given to the integration of design and construction, and the role of the designer throughout the construction phase. The implementation of risk management in the design and construction of tunnel works is discussed, and recommendations are made on how risk, value and constructability can be integrated in project delivery. Recent practice in project procurement, particularly in the use of innovative collaborative forms of contract are described, and details of particular provisions for joint management of risk and problem resolution are provided. Finally, the relevance of the ITIG Code of Practice for Risk Management of Tunnel Works to good practice in project delivery is highlighted throughout the paper.

By M. N. Chandraprabha

This paper discusses the role of mineral-adapted acidiphilic microorganism Acidithiobacillus ferrooxidans on the beneficiation of arsenopyrite containing multisulfides (pyrite and chalcopyrite). Adaptation to minerals altered the surface properties of the microorganism. Bacterial adaptation to arsenopyrite and controlled bacterial adhesion to mineral surfaces lead to selectivity in arsenopyrite separation. Bioremoval of arsenic ions (both arsenite and arsenate ions) by Acidithiobacillus ferrooxidans is also discussed.

Jan 1, 2009

In the present study, we have investigated the conditions for the formation of bubble clusters and the effect of well-defined agitation on the stability of clusters. A specially designed cell was used in which bubble clusters could be formed at the surface of a porous block in a fluidized bed of relatively coarse hydrophobic silica particles. The clusters then rose through a flow field of known turbulent characteristics. The size of the clusters before and after passing through the turbulent zone were measured using a high speed camera. The influence of shear rate on the deformation of the bubble clusters was investigated. The results showed that the Kolmogarov microscale was much smaller than the maximum cluster size, suggesting that the breakage of the clusters was mainly due to interaction with clusters in the inertial convection sub-range.

Jan 1, 2009

By Y. Wang

China is a big mining country with a long mining tradition and history. At present, there are nearly 200,000 different mines and 21 million workers. The total production value of mining makes up 6% of GNP. With the development of economy, the mining industry has played a more important role in our economic market, supplying more than 95% non-reusable energy, 85% of industrial and agricultural raw materials, over 75% of fertilizers and 30% industrial and agricultural water.

Jan 1, 2001

By Satoshi Honda, Mitsuru Shimizu, Tatsuji Nagao, Motoaki Kurisu, Hirokazu Izumi, Toshinori Takahashi, Hiroyuki Itoi

"1. INTRODUCTION Grade separation of roads and railway tracks is an effective method for solving traffic-related issues in cities. However, in urban areas where the existing traffic infrastructure is already overcrowded, construction of new roads often faces problems especially in the proximity of existing structures. This paper summarizes the construction plan and results of new road tunnel construction in the proximity of the piers of elevated tracks on the Tokaido Shinkansen railway.2. SUMMARY OF CONSTRUCTION AND ISSUES Auxiliary Route No. 26 as specified in the Tokyo urban plan is a project by the Tokyo Metropolitan Government, covering the construction of a new road with a total length of 22.3 km currently on the way to completion. In Shinagawa Ward, Tokyo, Auxiliary Route No. 26 is designed to cross the railway tracks of the Yokosuka Line and the Tokaido Shinkansen Line, so for this project, the East Japan Railway Company (JR East) was commissioned to design and build a road crossing under the railway tracks (Sumiyoshi Underpass). Figures 1 through 3 show a sketch of the Sumiyoshi Underpass. The Sumiyoshi Underpass was planned as a two-lane tunnel for vehicles, which was to cross under the railway tracks of the Yokosuka Line and the Tokaido Shinkansen Line at an angle of 70 degrees. The structure concerned is a single-story single-span box culvert structure with the following dimensions: 11.5 m wide, 7.7 m high and 31.6 m long. The Tokaido Shinkansen Line tracks were constructed on a girder-type elevated bridge built in the 1960s, and the foundation piles of the piers (P7 and P8) in the proximity of this crossing box culvert of RC structure were constructed using an earth drill method. The crossing structure for this project is located extremely close to the piers of the Tokaido Shinkansen railway tracks, with a minimal separation of 0.4 m, and the most significant issue of this project was construction in a manner that would not obstruct the normal operations of the Tokaido Shinkansen (Figure 4). Initially, we considered installing a temporary earth retaining structure in the proximity of the piers, cutting the ground and building an RC box, but concluded that it would be very difficult to apply this method because of probable excessive displacements in the Shinkansen railway piers. That is why we decided on the use of a non-open cut method in order to minimize the impact on the piers."

Jan 1, 2016

By Douglas E. Pollock

Recent NIOSH published information has shown an increase of rapidly progressive coal workers? pneumoconiosis (CWP) in the southern Appalachian coal region (SAR) of the U.S., despite the fact that compliance data indicates that most coal miners have been exposed to coal mine dust concentrations below the statutory limit of 2 mg/m³. While the exact cause of these elevated CWP levels in the SAR has not been established, several factors may be contributing to the increase in occupational lung disease among coal miners. The mining of high rank coal is known to lead to higher CWP rates, and this type of coal is mined in a portion of this region. Also, a high percentage of the mines in the region are on reduced dust standards because of the high silica content of the airborne dust resulting in miners possibly being exposed to excessive amounts of respirable silica dust. Exposure to excessive amounts of respirable silica dust can lead to silicosis, a disabling and potentially fatal lung disease. NIOSH?s Respiratory Hazards Control Branch has been investigating the possible causes that would account for the observed higher trends in disease progression through literature review, data analysis and in-mine surveying. The investigation to date has revealed that underground mines are faced with cutting large amounts of rock in order to maintain haulage clearances. Cutting rock not only increases the potential for silica exposure, it increases the requirement for machine maintenance, which was a concern observed during dust surveys conducted by NIOSH. Over half of the mines operating in the SAR are on reduced standards due to high silica content. Adequate face ventilation of the continuous miner and roof bolter and limited down-wind operations from the miner are also issues of concern and items that require the constant attention of miners operating in these conditions.

Jan 2, 2010

By Paul Nicholas, Raju Gottumukkala

"India’s economy is expanding with rapid urbanization. Improvement in infrastructure is a keystone to the Indian government’s economic plans, including expansion of transit systems. Most of these systems are designed with elevated and underground sections. New Delhi, a city of 23 million people, suffers from heavy traffic congestion and pollution. The transit (metro) system is seen to be of critical importance. Phase 3 of the Delhi transit system project is 140 kilometers (km), with 40 km of twin-bore tunnels requiring 35 tunnel boring machines (TBMs) for construction. Transit systems are also under design or construction in Chennai, Bangalore, Kolkata, Hyderabad, Jaipur and Mumbai. Most have twin-bore tunnels. At present, 55 TBMs are operating on underground metro construction, and future projects will increase this number. This paper highlights the unique challenges of construction of underground metro systems in highly congested urban environments, using Kolkata and Delhi systems as examples. INTRODUCTION The first transit system in India was constructed in Kolkata (India’s third-largest city by population.) This line is 28 kilometers (km) in length, has underground and at-grade sections, was built in phases, runs north/south, and has 24 stations. This project was sanctioned in 1972, started construction in 1984, and was completed in 1995. The tunnels were constructed primarily by cut and cover methods with some open-face, compressed air shield tunneling. In 2006, the urban transport policy recommended construction of transit rail systems in all urban cities with a population exceeding 2 million. Further, in 2014 the central government stated that it would assist in financing transit systems in all cities with a population of over 1 million. In 2015, the central government approved the development of transit systems in 50 additional cities across India with a budget of $75 billion (see Figure 1). Transit development is just part of a huge expansion in planned rapid transport systems, which include metro, bus, high-speed rail, and monorail systems. Metro systems will include elevated and underground sections with twin-bore tunnels and underground stations. In the Delhi/National Capital Region (NCR), now the largest city in India by population, Delhi Metro Rail Corp (DMRC) was formed in 1995 as a joint venture company between the central government and Delhi state. DMRC operates the Delhi metro system. (see the case studies described later in this paper). DMRC has developed an external function to carry out studies and to offer consultancy to other cities planning transits. Since its inception, DMRC has produced Detailed Project Reports (DPRs) for every metro and monorail project in India. In 2012, DMRC became a partner in the management consultancy for Jakarta Mass Rapid Transit System, its first project overseas. DMRC became a model organization for other cities to follow. These cities have included Chennai, Hyderabad, Kolkata, Bangalore, Jaipur, Mumbai, Ahmedabad, and Nagpur. Other cities (e.g., Lucknow and Patna) are in the metro planning phase. Metro systems are under construction or partially operating in Hyderabad, Bangalore, and Jaipur."

Jan 1, 2016

By W. P. Barnett

In 1988, the U.S. Department of Energy's Pittsburgh Energy Technology Center identified three coal cleaning options for achieving flexible environmental control strategies aimed at reducing energy-related SO2 emissions. These are selective agglomeration, advanced froth flotation, and advanced cycloning. Each technology relies on maximum liberation of pyrite and other mineral matter through feed coal comminution to fine and ultrafine sizes. Research projects designed to expeditiously develop each of these technologies to the point of commercial viability were initiated. This paper will present the status of these projects and the application potential of each technology to coal beneficiation.

Jan 1, 1992

By Michael A. Werner

"A Yieldable Structure for Use in Areas of High Rock Stress & Deformation." Rock stress of up to 9000 psi have been recorded in the mines of the Coeur d'Alene Mining district. Associated with these large stresses are rock fractures and deformation. In order to maintain openings required for mining, large wood preparation structures are constructed to provide access to the work areas for men and materials. These wood raise preparation structures are costly to construct and maintain. Therefore a steel-foam concrete structure was designed and proposed for testing which would be less costly to construct, require no maintainence and maintain its structural integrity while allowing up to 53 inches of wall rock deformation.

Jan 1, 1984

By John E. Good

A new coal boom is under way in western Canada. As recently as the mid-1960's, the coal industry in western Canada was considered stagnant and, by some people, dying. But Japan's growing need for coking coal, which became more pronounced in 1966, sparked great interest in western Canadian reserves.' As a result of a rapidly expanding export market and growth in domestic demand, Canadian coal production spurted to 16.6 million tons in 1970. Production in 1965 was 11.5 million tons. Today, about 60 percent of Canada's output comes from western Canada, but by 1975, 87 percent (23.1 million tons) is expected to come from this area, and 96 percent (68.3 million tons) by 1990. Opening, developing and operating new coal mines to meet the needs of a rapidly expanding market for western Canadian metallurgical coals pose some unique and difficult problems. Covering nearly every aspect of opening properties in remote areas, the problems are met in exploration, transportation, construction, mine operations, coal preparation, manpower and ecology. Paul Weir Company has been involved as coal consultants on various projects in western Canada for some years. In presenting this paper, we make no attempt to present an in-depth or detailed analysis of any one specific situation. Each has, or would have, its own peculiarities or characteristics, both physical and economic. Instead, the objective is to provide for those not intimately

Jan 1, 1972

By M. C. Roberts

Currently, mineral producers are suffering through a major downturn in prices for their products, even though it has only been a few years since they were enjoying high prices. From an historical perspective, the current situation is another of the cyclical down-turns that often reoccur every 5 to 7 years or so. This paper uses time trend decomposition techniques to identify the cycles and statistical methods to find the duration of these cycles for a variety of mineral prices. Given some idea of how long and severe these cycles typically are, the mining industry can better plan to weather the downturns and take advantage of the upturns. For example, timing investments in new projects to take advantage of the cyclical upturns can dramatically improve project profitability.

Jan 1, 2000

By J. Winterton

Cripple Creek and Victor Gold Mining Co. is developing a full-scale pad injection program as part of the overall operational plan for the Valley Leach Facility. As part of the development process the mechanics of the injection methodology are evaluated in the context of physical injection measurements, outcome from geophysical monitoring, and gold leaching theory. The results indicate that hydraulic fracturing analogies advanced heretofore do not accurately describe injection phenomena in unconsolidated and noncohesive material typical of leach pads. A new interpretation is presented and extended to define operational strategies for maximizing gold production.

Feb 27, 2013

By C. F. Barter, H. G. Kreis, D. S. Weber

Before and during in situ mining at the Santa Cruz In Situ Copper Mining Research Project test site, hydraulic testing was conducted at injection and recovery test wells to characterize patterns of fluid movement in the 5-spot well field. Testing included borehole spinner flow meter surveys, single-well and multiple-well injection and recovery tests, straddle packer injection tests, and bromide pulse tracer tests. Results of hydraulic testing for determination of fluid flow regimes were used to modify well and mining zone hydraulics for the purpose of increasing fluid migration in flow pathways of the mining zone with higher copper grade.

Jan 1, 2000

By W. H. Pomroy

In its 2001 diesel particulate matter (DPM) rule for metal and nonmetal underground mines, MSHA established an interim concentration limit of 400 micrograms of total carbon (TC) per cubic meter of air (400TCµg/m3), and a final concentration limit of 160TCµg/m3, to be phased in over five years. Following a court challenge to the 2001 rule, MSHA, industry and organized labor reached a partial settlement of the litigation under which the agency agreed to issue a proposal to amend the 2001 rule by, among other things, changing the surrogate from TC to elemental carbon (EC), applying MSHA's traditional hierarchy of controls, and revising requirements for one-year special extensions for complying with the final DPM exposure limit. MSHA issued a final rule in 2005 converting the interim concentration limit from 400TCµg/m3 to 308 micrograms of EC per cubic meter of air (308ECµg/m3) based on a miner?s personal exposure. Pending further rulemaking, MSHA retained the final concentration limit of 160TCµg/m3. In May 2006, MSHA issued a final rule that clarified that the final limit of 160TCµg/m3 would be based on a miner?s personal exposure rather than as a concentration limit. The 2006 rule also phased in the final DPM limit in three steps over two years, beginning in May 2006 at 308ECµg/m3, followed eight months later in January 2007 with a limit of 350TCµg/m3, and finally reaching 160TCµg/m3 in May 2008. Also in the 2006 rule, MSHA committed to converting the 160TCµg/m3 limit to an EC limit in future rulemaking. This paper reviews the DPM exposure limits in the context of the MSHA rulemakings and discusses the DPM engineering controls that were utilized by mine operators to attain compliance with each progressively lower limit.

Jan 1, 2009

By Syd S. Peng

Coal mine ground control is the science of the application of rock mechanics principles to coal mining operations. More acceptance of ground control techniques by the US coal mining industry has been seen in the 1980s. It has been demonstrated many times that a proper ground control design is key to a successful coal mining operation. However, numerous in-mine applications of various ground control techniques by the author indicate that cur¬rent techniques need improvement. The biggest problem in coal mine ground control is that miners are dealing with materials of rapidly varying properties and occurrence. And only the exposed surface can be identified positively. Thus, in attempting to solve the ground control problems, many unknown factors are assumed. Some of these problems deriving from such assumptions are discussed here. Coal pillars There are two types of coal pillars - barrier and chain pillars - depending on the purpose. Barrier pillars are those located between panels or sections or mines. Their objective is to isolate the mined-out effects of one from the other. Chain pillars are characteristic of room-and-pillar mining. They are designed to support the overburden load and protect the surrounding entries and crosscuts. Pillar design is the most popular and, frequently, the only ground control technique employed by coal operators for mine design. There are many pillar design formulae available (Bieniawski, 1983; Peng, 1986). Nearly all consider both size and width/height effects. Specifically, pillar strength decreases with increases in pillar size and increases with increase in the ratio of width to height. However, the manner of those changes varies with investigators. Consequently, the pillar size determined varies considerably from investigator to investigator. And the variation grows much more pronounced as the seam depth increases (Fig. 1). The question, then, is which one should be used? One may say each formula is developed for a particular coalfield. A particular formula may have been used to design a pillar, which has not failed. Does that mean it was over designed? Not necessarily, because no one can confirm its stated "safety factor." Recent case studies (Peng, 1986; Tang and Peng, 1988) show that all pillar formulae are too conservative for chain pillar design in room-and-pillar mines due to the following two problems: • Uncertainty about in situ pillar strength. All formulae employ uniaxial compressive strength of selected samples tested in the laboratory and scaled to that for underground pillars. The scaling factors are not well proven. In situ testings by Bieniawski (1969) suggested that 1.5 m (5 ft) pillars are representative of in situ pillars that, after being tested in various US coal mines, are not universally applicable. • Uncertainty about the actual loading on the pillar. The most frequently used tributary loading theory defines the loading as total overburden weight tributary to each pillar (from roofline to surface). This is too conservative when it applies to coal measure rocks. The overburden consists of layered strata of different stiffness. Many stiffer strata will self-support over small roof spans. Depending on the location of these strata above the coal seam, it will reduce pillar loading in various proportions. It follows that total structural analysis using, for instance, finite element method is more appropriate. It can take into account the interaction of roof and floor strata with coal. This has been demonstrated by Peng et al. (1986,1988) on several case studies. However, the validity of the finite element structural analysis depends on the accuracy of in

Jan 1, 1989

By E. Steiakakis, A. Athousaki

Nowadays, stakeholders have a strong say to the enforcement of best practices by mining and quarrying companies. In most cases there is a direct relationship between sustainable development principles and best practices. Mining companies try to apply best practices in order to sustain their operation without lost time and effort to litigation, and other obstacles. However, when and where there is a lack of state or regional mineral policy, or when the mineral policy is fragmented and touching on conflicting laws, mining operations may be subject to additional administrative hassles, and, thus, operators feel threatened and tend to apply best practices loosely. This paper argues that the only way that mining and minerals operations can be a source of development is to ensure that they are working within the framework of sustainable development. Furthermore, in order to follow the paradigm of sustainable development they would need to be guided by a regional, national or even transnational (i.e. European) minerals policy.

Jan 1, 2011

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 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