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By K. M. Atencio, T. Pike, S. Forrest

We will introduce the Small Business Liability Relief and Brownfields Revitalization Act, which is an amendment to CERCLA and the types of sites it includes and excludes, especially as related to mine-scarred land. We will also describe the types of available funds, whether they are competitive or not, what entities are eligible to receive them, and how to access them. We will introduce the legislation’s liability provisions; for example, the recently issued interim guidance clarifying some of the conditions that contiguous property owners, bona fide prospective purchasers, or innocent landowners must meet to qualify for the liability limitations provided in the Brownfields Law.

Jan 1, 2004

By Paul F. Saxton

Introduction As the world economies continue to face an increased demand for natural resources to support growth in the established and developing world, the western mining industry has expanded its operations and funding of mineral developments into new and relatively unexplored regions of the world. Mining companies worldwide, in order to grow in a global economy, are now actively exploring and developing mineral resources in the emerging markets of South and Central America and most recently have expanded activities throughout Asia. South East Asia Resources (S.E.A. Resources) has recognized the vast resource potential offered by countries such as China, India and Indonesia, Asia's main driving forces of economic growth and has made a commitment to be actively involved in the area. These countries rich in mineral resources, represent some of the highly prospective and underexplored regions on earth. Their vast potential has been underestimated because of political reasons and overlooked as Central and South America still continue to be the focus of exploration for many mining companies. Most of these Asian countries have faced a prolonged period of political unrest and it has not been until recently that they have begun to enjoy a relatively stable political climate which has encouraged foreign investment, growth and economic development. These countries are in need of capital to develop their infrastructure and market economies. Their wealth in resources is one of the best methods to achieve their goals. Gold is usually one of the first targets to be extracted from developing economies. Equivalent-sized gold projects tend to cost less to develop and require less supporting infrastructure than base metals. These projects are easier to finance and, most important of all, tend to give a quicker return on investment than that offered by base metals. They also provide the economy with precious foreign exchange, international investment and the technology required to build the country. Following is a graph representing the global re-allocation of the total capital investment on the twenty largest gold projects now under construction with the total for those under construction in 1990.

Jan 1, 1996

By Laura J. Carroll, Gordon A. Goldsmith

Experts, like many of the speakers at the SME Annual Conference, are frequently called upon by lawyers to assist them in litigation. Due to the technical nature of many cases, the testimony of an expert with knowledge and experience in a particular field is necessary to help a judge or jury understand and decide certain issues. Environmental litigation is no exception. Experts routinely are called upon to offer testimony to establish the existence of contamination and its source, as well as the potential health and environmental risks associated with the contaminants. This article will briefly discuss the factors courts apply to determine whether to admit expert testimony after the recent Supreme Court decision in Daubert v. Memell Dow Pharm., Inc., 509 U.S. 579 (1993). The Court's decision in Daubert overruled a long-standing test that had based the admissibility of scientific evidence on its "general acceptance" in the field in issue. Next, the article will discuss in general terms what a party must do to "link a particular defendant's conduct to the contamination involved in order to recover from that defendant. This link, known as causation, varies depending upon the type of claim being asserted. Expert witnesses are used extensively to help establish causation. JUNK SCIENCE OR GOOD SCIENCE- HOW DOES A COURT DETERMINE WHAT TO LET IN A frequent complaint in litigation involving technical or scientific issues is that one party or another is trying to use so-called "junk science" to prove its case. While some expert testimony might be so clearly lacking in support or so "off the wall" that a court can easily determine to exclude it, other testimony, especially testimony on the "cutting edge," is much more problematic. In 1923, the District of Columbia Circuit Court of Appeals decided the case of Frye v. United States, 293 E 1013 (1923). In deciding whether to admit certain expert testimony, the court in Frye stated that while a court will "go a long way in admitting expert testimony deduced from a well-recognized scientific

Jan 1, 1998

By F. L. Wilke

Truck haulage costs form a major part of the total mining costs in hard rock open pit, mining operations. In order to minimize these costs one has to - determine the optimal truck fleet (type, size and number of trucks), and. simultaneously - determine the optimal organization of running the haulage system, i.e. especially select the optimal dispatching strategy in order to ensure maximal utilization of the trucks, and simultaneously - establish a reliable maintenance and servicing system to guarantee maximal availability.

Jan 1, 1982

By M. H. Pelkki, R. J. Sweigard, P. W. Conrad, J. M. Ringe, D. H. Graves

Research has shown that excessive soil compaction is detrimental to the establishment of trees in reclaimed soils. Dry bulk density and penetration resistance are two soil parameters that can be used to indicate the level of compaction in reclaimed soils. It is believed that reclamation practices which minimize soil compaction will produce better results when forestland is the intended post-mining use. The University of Kentucky has developed reforestation test cells on reclaimed soils at a surface mine in eastern Kentucky to test this hypothesis. Each test cell has been planted with various species of trees, and since 1997, data have been collected at these test cells for soil average dry bulk density, average penetration resistance, average depth to refusal, and average survival rate of trees. These data have been correlated to determine the relationship between soil compaction and tree survival rate. It is believed that the two soil compaction parameters may ultimately be used to predict tree survival rates on reclaimed surface mined lands.

Jan 1, 2001

By Z. F. Wang, W. K. Choi, A. E. Torma

The present study has investigated the bioleachability of low-grade and high-grade pyritic gold ores and the extraction of gold from the leach residues of bioleaching with thiourea solutions. Final gold extractions as high as 96% were obtained from the high-grade ore and above 93% from the low-grade ore. The gold extraction was found to follow the extent of pyrite biooxidation. Using a cyclic voltammetric technique and carbon-paste-FeS2 electrode it was found that the semiconductor pyrite oxidation involves many intermediate electrochemical reactions. Furthermore, the oxidation is solid-state diffusion controlled as suggested by chronoamperometric and chronopotentiometric measurements.Using Sand's approach, the activation energy of solid-state diffusion biooxidation of pyrite was determined to be AEa=22.4 kJ. A generalized model for the mechanisms of pyrite oxidation has been presented.

Jan 1, 1990

By John Wiebmer

Several industry trends are putting new demands on surface mining equipment. This is true both on the “hard” side of the equipment business - the research and product development programs, and on the “soft” side - the business processes, human resources and competitive strategies. This article describes seven key industry trends and the impact each is having on surface mining equipment suppliers. 1. Globalization Earth-spanning technologies are shrinking the world into an economic village, causing corporations to think and plan on a global scale. This “globalization” is one of the great buzzwords of the 1990s, meaning precisely whatever the user says it means. In this case, let us take it to mean that political boundaries arc less restrictive than in the past, permitting mining companies new freedom to roam the globe for ore bodies. Evolving out of this are global mining houses that have ownership and management interests in labyrinthian webs of mines spanning the world. There are several impacts on surface mining equipment suppliers.

Jan 1, 1994

By Chapman Young, Donald E. McCarthy

Many hard rock tunneling projects, where the majority of excavation can be accomplished with TBMs, will still require considerable specialized excavation which can not be done with a TBM. This secondary excavation, involving cross cuts, galleries, flattening of the invert, increases in bore diameter, et cetera, may be accomplished with conventional drill and blast, applied on a small scale and usually with fracture control techniques, or with mechanical splitters. The problems of using explosives in many of these cases and the high cost of mechanical splitting excavation make the consideration of other approaches attractive. The PCF rock excavation method, which has recently been reduced to commercial practice for mine-development excavation, offers an attractive alternative to drill and blast and mechanical splitters. With the PCF method the rock is excavated utilizing a small-charge, propellant-driven, controlled, penetrating-cone fracture process. Excavation is carried out continuously by combining the PCF hardware with integrated mucking capabilities on a carrier which remains at the excavation point. In addition to the benefit of providing for complicated excavation geometry, the PCF method also causes minimal damage to the remaining rock which will significantly reduce ground support requirements. In very bad ground, the continuous nature of PCF excavation allows ground support to be applied as limited sections are exposed thus reducing both the duration and extent that the ground would be free to move. Data on PCF excavation parameters, as measured in actual mining operations, indicate that crosscuts, galleries and the like could be excavated at considerable cost savings compared to drill and blast or mechanical splitters.

Jan 1, 1995

By G. L. Merritt

The implementation of the Surface Mining Control and Reclamation Act of 1977 (SMCRA) has evolved into one of the most complex environmental protection programs to come out of the late 1970's. The level of detail in the statute and the regulations have resulted in a rigid and complex set of requirements for the administration, permit-ting, inspection and enforcement of the program. In addition, the constant change of the federal program caused by regulatory changes, reorganization of the Office of Sur-face Mining Reclamation and Enforcement (OSMRE), ongoing litigation involving OSMRE, and the use of the budget to establish additional mandates on OSMRE and the State Regulatory Authorities have resulted in an unstable program. The instability of the program makes it extremely difficult for the States to implement their programs and to achieve the goals of SMCRA.

Jan 1, 1988

In general, it cannot be assumed that the strength of coal pillars remains constant over long periods of time. Field observations indicate that a coal seam, especially when it contains a parting layer, deteriorates over time, reducing the load-bearing capacity of the pillars. This paper discusses a unique approach to determining the time-dependent strength of coal pillars in the field. Three coal pillars that were developed 5, 15, and 50 years ago were chosen for the study. Holes were drilled in coal and parting layers in each pillar, and the strength profiles were determined for each hole using a borehole penetrometer. The strength data were treated statistically to establish time-dependent strength equations for different layers. The results can be used to help estimate the loss of pillar capacity over time.

Jan 1, 2012

By A. W. Popp

After forty years of exploration and development, the heavy mineral sand deposits of the Murray Basin are on the eve of substantial exploitation by Iluka Resources Limited, Southern Titanium NL and RZM/Cable/Bemax, whom plan to initiate mining and processing operations in 2005. A trial mining and processing operation was undertaken on the Wemen North strandline deposit in 2001-2003 by Murray Basin Titanium, a joint venture of Sons of Gwalia and RZM/Cable, which brought to light a number of mining and processing problems which have since been the subject of extensive studies and process development work. The mineralogy of these weathered strandline deposits is complex by industry standards due to the variety of the heavy minerals present, coatings on the mineral grains and the extensive weathering and alteration which has taken place during the past 50 million years. This paper provides an overview of the complex mineralogy that, in turn, dictates the processes that can be used to recover the valuable heavy minerals. The Murray Basin encompasses some 300,000 km2 and has been a depositional basin, often land locked, since the start of the Cenezoic Era. The economic heavy minerals include ilmenite, altered ilmenite, leucoxene of highly variable composition, rutile, and zircon. There are also other heavy minerals present such as cassiterite, chromite, and monazite in quantities that pose both problems and opportunities. The clay content and overburden thickness also play a major role in the selection of the deposits to be mined. Project Services Consultants (PSC) has undertaken the preparation of this paper as part of its ongoing participation in the mineral sands industry and in particular the project development activities in the Murray Basin region currently being undertaken by Iluka Resources. PSC has been involved with the mineral sands business for several years with senior staff having in excess of 30 years global industry experience. The company is well placed to provide a range of services to clients like Iluka Resources in the areas of project development, execution and strategic development and industry advice.

Jan 1, 2005

By M. E. Lewellyn

A new class of thionocarbamates, O-alkyl-N-allyl thionocarbamate (III), has been found to give better metallurgy than 0-isopropyl-N-ethyl thionocarbamate (I) for a number of sulfide ores containing copper, lead, and zinc. Data on the results of flotation tests with several such ores are presented. The improved metallurgy is believed to be due to the participation of the allyl double bond in the complex formation of the thionocarbamate on the surface of the mineral.

Jan 1, 1985

By T. J. Harvey, W. van der Merwe, J. Joubert

GeoBiotics, LLC and Kumba Resources (Pty) Ltd are jointly developing the GEOCOAT® heap bioleaching technology and downstream processing technology for recovery of zinc from tailings at the Rosh Pinah Mine in Namibia. This paper outlines the development of a computer simulation for the bioleaching of sphalerite and the downstream processing. Computer modeling has shortened the product development cycle by allowing many flowsheet scenarios to be analyzed negating much of the expensive and time consuming laboratory testing. A model was developed using the Limn® system which is an Excel® Add-In flowsheet drawing and solution engine. Given that most engineers are familiar with Excel® this software is extremely easy to use and has less hidden calculations making model verification much easier.

Jan 1, 2003

In June, 1,334 underground construction and tunneling professionals gathered in Toronto, Ontario for the 2007 Rapid Excavation and Tunneling Conference (RETC). This biennial event, sponsored by SME, is one of the global underground construction industry?s major events. And this year?s RETC was the first one that included the new Underground Construction Association. [ ] (UCA) of SME. In addition, the conference?s exhibit attracted 125 equipment and service providers. The next Rapid Excavation and Tunneling Conference is set for June 14-17, 2009 at Caesar?s Palace, Las Vegas, NV.

Jan 1, 2007

By Janusz S. Laskowski

Studies carried out over the last 10 years reveal that precipitating particles which may appear in alkaline solutions of long-chain amines and in acidic solutions of fatty acids exhibit clear isoelectric points around pH 10.6-1 1 for dodecylamine and around pH 2.5-3 for fatty acids. These colloidal species can accumulate at solid/liquid and liquid/gas interfaces and affect flotation. While the precipitate in solutions of fatty acids apparently can chemically interact with the mineral surfaces and is flotation-active if sufficiently long conditioning time is available, the cationic flotation of quartz in alkaline solutions is depressed by the colloidal precipitate. The experimental data available in literature on the adsorption, electrokinetic, contact angle and surface forces measurements in the solutions of the weak electrolyte collectors are analyzed and the role played by the precipitate is discussed. It is shown that these concepts allow for an explanation of the selective flotation of sylvite from halite with long-chain amines in potash ore flotation.

Jan 1, 1999

By F. M. Benavides

This paper presents recent developments in federal environmental regulations, which in the view of the author, affect mining and the mineral processing industries. This is a summary of activities by the administration, congress and regulatory agencies during 1990. The information presented is a recap from material published. The emphasis is given to Air Quality regulations, although other environmental concerns are reviewed.

Jan 1, 1991

By T. Cienski

The paper presents and discusses the results of a detailed study conducted on the subject of energy consumption in the comminution of industrial minerals. The study was based on pilot circuit testing, plant operating data collection, detailed equipment data and literature research. The areas covered by investigations include: high efficiency classification; air classifiers for cement grinding circuits; grinding aids in dry grinding: dry grinding circuit, control based on particle size measurement. Results obtained indicate a large potential for the reduction of energy consumption, in particular in the traditionally high cement clinker grinding circuits. Better classification techniques and correct application of grinding additives can significantly reduce power used per ton of product and also substantially increase grinding circuit output.

Jan 1, 1990

By A. R. Laplante

A novel methodology to estimate gold recovery by gravity is presented. The methodology makes use of a population balance model which represents gold liberation, breakage and classification behaviour and applies pre-concentration and recovery performance curves to gravity-recoverable gold to predict overall recovery. Derivation of the necessary parameters is explained and demonstrated using data from an actual gravity circuit and one projected application. The methodology makes it possible to estimate the performance of circuits with large gold circulating loads and relatively low unit recoveries (e.g. jigs), or with high recoveries on a bleed of the circulating load (e.g. Knelson concentrators).

Jan 1, 1994

By J. Hebert, J. Donnelli, J. Sedey

Installation of a Load Commutated Inverter (LCI) provides an economical method for conversion of a Fixed Speed Semi-Autogenous Grinding Mill into one with variable speed, qualities. Though capital intensive, the conversion appears to be one of the most cost-effective methods to gain the advantage of critical speed variations for variable ore characteristics. Expected advantages from the installation of LCI drives at the Goldstrike Mine were decreased liner wear, decreased media consumption and additional grind for increased production rates. These issues as well as construction, economics and performance will be discussed in the presentation. The utilization of the existing equipment came to play an integral part of the study and economic justification of the overall project.

Jan 1, 1999

By G. Gregory Bryan

G. GREGORY BRYAN 33.1-DEFINITIONS 1. Engineering-Engineering may be defined simply as the science and art of making materials and energy serve the purposes of mankind. There are many fields of engineering, each with specialized branches. The basic fields are: civil, mechanical, electrical and chemical. Others may be specialized phases of one of these or a combination of two or more of them. Mining engineering, for example, requires a working knowledge of construction, mechanics, electricity, metallurgy, geology, accounting and economics, in addition to mining techniques or methods. Mining geology and geological engineering involve rocks and their structure and the forces that act upon them, and chemistry, physics and mechanics also are important to practitioners in these fields. Metallurgical engineering requires chemistry and physics but also a working knowledge of mechanics and electricity. The fields of engineering with which this section are concerned are those primarily involved in the finding, mining, processing and utilization of the natural mineral resources of the earth. They include geology, mining engineering and metallurgy, each with several specialized subdivisions. 2. The Engineer-The engineer is an individual who has had specialized training to qualify him to practice the profession of engineering. The term engineer is used here in its broadest sense to include such professions as certain applied branches of geology, physics and chemistry, whose practitioners may not have acquired engineering degrees but who, nevertheless, by training and experience in some area of the minerals industry, qualify under the above definition. To become a successful engineer, a person should have certain pronounced aptitudes and preferences, even before embarking upon the requisite course of training. Among the chief qualifications that the engineer-to-he must possess are: (a) a natural inclination toward mathematics and the physical sciences, and (b) intellectual and moral honesty. Among the qualities the student engineer must develop are: (a) independence of thought, open-mindedness, sound judgment and the ability to observe, deduce, plan and apply solutions, (b) the ability to articulate and convince, and (c) the ability to organize and direct the activity of others. These qualities are normally developed through sound education, followed by pro¬gressive experience. 3. The Consulting Engineer-The consulting engineer is an engineer primarily in the business of furnishing specialized advice and engineering services on an intermit¬tent, part-time or occasional basis to clients who do not have continuous or full-time need for those services. He must be able to make and take full responsibility for decisions and recom¬mendations where original thought is required. He should not be confused with the engineer, surveyor or technician who also may furnish services on an intermittent basis, such as regular periodic surveys, the overseeing of drilling programs and other such routine work as may require little original thought and planning. 33.2-THE PROFESSION OF CONSULTING ENGINEERING 33.2.1- QUALITIES REQUIRED A successful consulting engineer must first have, as a minimum, the qualities and preparation of an engineer. In addition, he must have sufficient knowledge,

Jan 1, 1973