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By R. J. Gary

Why would a company in its right management mind risk a fuel conversion program on a fuel that can't burn if it's too wet or too dry, too hot or too cold, too coarse or too fine, or doesn't have enough Btu's to supplement good combustion? On December 23, 1981, two months ago, we finished our first ten years of burning lignite -- this unconventional coal. It is from that experience that I am qualified to address you today. As some of you here probably already know, my company, Texas Utilities Generating Company, has pioneered the utilization of Texas lignite for electric power generation on a large scale, and I think it is fair to say that we have done this pioneering work largely on our own. Some of us feel like Noah did when he built the arc! I have titled this presentation "The First Lignite Decision" because our company was the first to make this major decision in Texas in the mid-1960's. It was a big decision, and at the time, perhaps a bold one. When you look at the conditions that existed in the mid-1960's, you can see why.

Jan 1, 1982

By H. Hejny

The objective of the project is to construct and operate a pan-European underground drainage and minewater management research centre, which would be the hub for data gathering and dissemination in real time of new data to users for analysis and interpretation, as well as serving as a model for consistency, for other centres at key water management sites throughout Europe which would feed data in real time through the hub. The data from the centre will be essential for informing River Basin Management Plans arising from the EU Water Framework Directive, which is an important driver for the project. The implementation of this Directive sets out a requirement for all Member States to develop River Basin Management Plans for all water resource systems. The facility would be a major contribution to sustainable water management in Europe.

Jan 1, 2007

By H. M. Conger

I'm really very pleased to be talking with you today about the environmental impacts of gold ore processing as part of this symposium on emerging process technologies for a cleaner environment. But before I talk about some of the newer developments that are coming, I would like to set the stage by reviewing some of the recent past. Over the last decade or so the U.S. gold mining industry has experienced remarkable growth, primarily in heap leaching operations, and not surprisingly there has been parallel growth of environmental regulations. At Homestake, we have had the excitement of bringing on-line a new mine embodying state-of-the-art technology and environmental planning, and during the same period the flagship of our company, the Homestake mine, has been brought into modern day compliance through the application of innovative environmental technology. This has been a learning process; in both cases we found that we had to develop new ways to meet our objectives. At our McLaughlin mine in California a major achievement was pioneering the use of pressure oxidation, or autoclaves, for refractory gold ores, and at the Homestake it was the development of a unique bio-treatment plant for wastewater. These projects were developed balancing operational goals, environmental concerns and costs, and I would submit that being cost-effective is our greatest challenge in the development of new, environmentally sound, process technology. In meeting that challenge, our job has not been made any easier by the myriad environmental laws and regulations that directly affect the design and operation of our facilities. Most of these constraints have evolved through the political process more or less independently, but in their application there often are over-lapping provisions. Adding to this complexity is the fact that action takes place in both state and federal arenas. As a result, state and federal roles sometimes become intertwined, and a good case in point is provided by various cyanide issues faced by gold producers. The vast majority of U.S. gold mining takes place in the so-called "mineral States," the western States that come under the Mining Law of 1872 as amended. This is the basic statute that provides for access and tenure to develop mineral resources on federal lands in those states. There is gold mining outside the defined mineral States, and there is also gold mining in the mineral States on private lands. Our own Homestake mine in South Dakota is one of the best examples of the latter category: located entirely on private land, it is nevertheless subject to at least 13 federal environmental statutes and some 29 federal regulatory requirements. There are also nine significant state statutory and regulatory requirements that apply. On federal lands in the mineral States there are numerous federal statutes and regulations which affect mining, over and above the current Mining Law. These, which are in addition to the laws applying to private land, include the National Environmental Protection Act and the Federal Land Policy and Management Act, among others. Still, those who advocate radical changes in the basic Mining Law would have us believe that sweeping environmental protection and reclamation provisions, not to mention new land use restrictions, are needed. Such changes could effectively prohibit mining on the federal public lands. Strict enforcement of our current Mining Law would have presented most of the abuses cited by the critics but if the Law is to be changed at all, I believe that, at a minimum, the principles of self-initiation and security of tenure embodied in the present statute should be maintained. These are critically important concepts, but there are other statutory and regulatory issues constantly before us as gold miners. Let me cite a few examples: Reauthorization of RCRA There are several bills being considered by Congress to amend the Resource Conservation and Recovery Act (RCRA) that have as their theme

Jan 1, 1992

By William F. Lawrence

Within ten to fifteen years, coal-fired power generating stations will be producing over 40 million tons of coal-ash annually in the United States. The largest part of this ash will be emitted from the boilers, entrained in the off-gas stream and trapped as flyash. However, about 15 percent (six million tons) will he removed from furnace bottoms as bottom ash or molten coal-ash slag. In current practice, the molten coal-ash slap is generally water quenched and then transported either as a slurry or in granular form to storage or disposal areas. Although a small amount of this slag is marketed as abrasive grit or as roofing granules, most of it is considered a waste material which must be disposed of at considerable cost to the power companies and therefore to the public. The accom¬panying economic loss in terms of unused raw materials and displaced land is not as obvious but is just as real. The Coal Research Bureau at West Virginia University under the sponsorship of the U. S. Bureau of Mines has been examining the possible utilization of both coal-ash slag and flyash in the mineral wool industry as a method of partially alleviating the growing national problem of solid waste disposal. The potential marketing situation for mineral wool manufactured from coal-ash is illustrated in Figure 1. This bar graph depicts the growth in value of mineral wool shipments1 from 1949 through 1966. In this 17-year period, the value in¬creased by over 350 percent, more than 20 percent per year, despite a decrease in unit cost of mineral wool. It therefore appears likely that coal-ash could find a steady market as a supplement to existing sources of raw materials for mineral wool production.

Jan 1, 1970

By Allan M. Hale

Taconite tailings reclamation, especially the stabilization of tailings ponds, .dams, and slopes, can be effectively accomplished through the use of appropriate vegetation. Utilizing vegetation provides both aesthetic and ecological enhancement of a site while at the same time protecting tailings structures against wind and water erosion. Generally, the methods and techniques for establishing vegetation are well known; however, there are many site-specific factors that can alter a particular reclamation approach. Those factors include slope gradient, tailings material size, solar exposure, and physical and chemical properties of tailings. In addition to the site-specific factors, variations in climate, geography, and physiography of a region can have a pervasive influence on the success or failure of a revegetation program. Both the site-specific and regional factors control reclamation planning in such areas as plant variety selection, methods and times of plants establishment, maintenance techniques, and subsequent monitoring methods. As a result of this multifactor relationship, it is important to establish a data base that identifies both the site-specific and location conditions in order to tailor the reclamation plan to the specific area. When an appropriate data base has been collected, detailing the various site-specific and regional factors that will influence a revegetation program (in the absence of previous testing), it is very beneficial to apply experimental techniques to develop the reclamation plan for a specific site. The reclamation plan for a specific site may include several techniques adapted for the differences found within the specific site as the result of topographic or other influences. Considering this, the Reserve Mining Company and Dames & Moore undertook to develop a successful reclamation plan based on a detailed test plot program conducted at the Mile Post 7 location.

Jan 1, 1980

The mining industry has indeed gone global. International minerals producers are spending big money to move into countries that were off limits a few years ago. Due mostly to political reasons, these countries' huge mineral deposits - worth billions of dollars - were locked up and mining companies could only sit on the side and wonder "what if." Now much of the world is going the free market route. Once closed countries and developing nations are rewriting their mining and tax laws hoping to attract foreign investment to develop their natural resources. And big businesses - mining companies included - are lining up to get their share. But with new opportunities come new risks. While emerging nations are slowly accepting the free market concept and the privatization that goes along with it, many remain plagued with political instability and violence. Even developed nations carry their unique risks. Some of these include inadequate or contradictory legal and regulatory infrastructures, political patronage and outright corruption. So companies hoping to expand into new regions of the world must do more than examine the market. They must study the political stability and structure of a country, as well as its tax and environmental laws. And they must guarantee the safety of their employees. Control Risks Group is an international management consulting company that assists companies preparing to move into a new country. It employs about 225 people in 14 offices throughout the world. Control Risks personnel include lawyers, bankers and former law enforcement officers and intelligence people. The company held a one-day seminar in Washington, DC to update some of its clients on the state of affairs in various regions of the world. The seminar also covered extortion, corruption and product diversion. About 175 people attended the seminar. Speakers included Control Risks' operators, analysts and investigators. Here is a summary of what some of those people had to say.

Jan 1, 1998

By Greg Border

Many unique ventilation problems have been faced as Avery Island Mine's large openings have been mined. High humidity of outside air combines with the hygroscopic salt to create a corrosive atmosphere. Massive rooms preclude routine use of brattices to direct air flow to the working faces. Large amounts of explosives are consumed in single blasts. Resulting concussion pounds air control structures and ANFO ignition creates large amounts of nitrogen dioxide in single rooms. Geologic constraints confine new shafts and slopes to areas thought to be free of potential ground water hazards. Dust control techniques are limited by dry product demanded by customers. The Avery Island Mine's ventilation system has evolved to deal practically with the conditions and to dependably provide fresh air to the miners. International Salt Company's Avery Island Salt Mine, a multiple level room and pillar operation, has been mined steadily since about 1900. It is known as one of the "Five Island" salt dome mines of South Louisiana's Gulf Coast. Production from the area places Louisiana first in United States rock salt mined tonnage, according to the United States Bureau of Nines, 1982 (1). International Salt Company is a major force in U.S. salt production, as it also operates mines in Detroit, Michigan; Cleveland, Ohio; and Retsof, New York; a solar salt facility in Bonaire, Netherlands Antilles; and a solution mining plant at Watkins Glen, New York.

Jan 1, 1983

By D. U. Gustafsson

After half a million meters drilled with Wassara we are now confident that ITH hammers powered with simple water will become an established product for production drilling. Today four drill rigs in LKAB Malmberget equipped with Wassara drill about 25 000 m per month of 4 1/2" holes. In Kidd Creek, Canada, Was sara is used for production drilling in stopes with good results. The first Wassara 6" hammer has drilled a 36 meter long, completely straight horizontal cut hole for drifting in the LKAB Malmberget Mine. Main advantages are about doubled penetration rate, very good air quality and improved hole cleaning which facilitates stabilized drilling. Disadvantages are resistance to new technology and, in some cases, the increased use of water.

Jan 1, 1995

By J. O. Leppinen

FTIR measurements using a special ATR cell were carried out to investigate the adsorption of two thiol collectors, potassium ethyl xanthate (KEX) and sodium diethyl dithlophoshate (NaDTP), on an unoxidized lead sulfide surface. Both qualitative and quantitative determinations of the collectors were made at the coverages from two monolayers down to 2% of the monolayer. The experiments revealed that the thiol collector species coordinate to the lead atoms at the surface of lead sulfide but the surface products distinctly differ from the precipitated bulk lead compounds. There exists a linear relationship between the coverage and the signal intensity of the IR spectra within the coverage range studied.

Jan 1, 1987

By Duane A. Smith

Horace Tabor. No 19th century Colorado mining man is better known but, unfortunately, probably less understood. He is little appreciated for his significant contributions to the industry and the state. A century ago, Tabor was headline news. The legend today, however, has become so all pervasive and so interwoven with fact that the two are hard to separate. For example, he never told Baby Doe on his death bed to hang on to the Matchless mine. Yet this has emerged as staple Tabor fare. So much attention has been focused on his matrimonial triangle that it overshadows the man. Symbol of mining's reward Tabor traveled west in the 1859 Pike's Peak gold rush. In the next generation, he came to symbolize the rewards mining might lavish on an individual. The Leadville Daily Herald (Sept. 10, 1882) could write, without exaggeration, that "the extent which the mining industry of Colorado is under obligation to Tabor cannot be easily estimated - what he has done for Leadville and Denver is patent to all." It had not come easily, nor had Tabor started out a success. His early placer mining at Payne's Bar, near present-day Idaho Springs, CO, had turned no fortune. So in 1860, he, his wife Augusta, and son went south to Colorado City, then over Ute Pass and up the Arkansas Valley to Oro City. Arriving soon after the initial discovery, Tabor staked a good claim. With a sharp eye, he and Augusta broadened their base by establishing a store. Both mining and business would pay dividends in the following years. By the season's end, though, Oro City was already declining. Always on the lookout for a richer district, Tabor and his family moved the next year across the mountains to promising Buckskin Joe. The familiar pattern followed, with the store and post office being the center of their attention. Mining investment and management now replaced the earlier physical panning and sluice operating. Seven years later, the Tabors abandoned Buckskin Joe and returned to Oro City. It had moved up California Gulch to be near the district's best mine, the Printer Boy. Middle class was not enough Middle class respectability, plus a steady income, was the Tabor's by the 1870s; fine as far as it went. But it proved far from the fortune Horace had always been seeking. Oro City languished in the backwash of Colorado mining and Tabor seemed like many men who had drifted around the Territory following the ebb and flow of mining. His faithful wife Augusta had been a steady factor in the success the family achieved. She helped year after year to operate the store and post office. Not simply the happy-go-lucky individual he has often been portrayed, Tabor was a hard working businessman/mine owner. An R. G. Dun and Company agent evaluated him in 1876 "Net worth $23,200. Is a very shrewd businessman and not liable to lose money, has a good chance to make money as he had no competition." Leadville: Tabor's silverlined-fortune After all those years on the Colorado mining frontier, in 1877, Lake County's wealthiest and most respected merchant made another move. It was short in distance, only 4 km (2.5 miles) down California Gulch, then a little north to a new mining camp. This new camp, soon named Leadville, gave birth to the Tabor fortune and legend. Middle-aged (Horace was 47), the Tabors once more set up their general store and found themselves in the midst of the open¬ing of a new district. This time silver beckoned and not the gold that had brought them West 18 years before.

Jan 1, 1989

By S. Eugene Sankey, Geoffrey L. Payne

Fundamental choices in flocculant selection often come down to the lower cost of solid grade products versus the convenience of liquids. The ideal product would be a low cost solid grade flocculant which requires minimal handling and no sophisticated dissolving equipment. Recent polymer developments have lead to the commercialization of a limited range of dry polymers that can be screw fed at controlled rates directly to process streams without the need for predissolving. Other developments include dry polymers that can be directly added to mix tanks without the need for sophisticated wetting systems. The latter will make dry flocculants especially attractive for smaller users. Examples of these new products and their application in industrial and municipal waste treatment will be provided.

Jan 1, 1994

By M. C. Roberts

Metal producers are now 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 downturns that often occur every five to seven years. 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 metal 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, 2003

By L. U. Spellman

Atlantic Cement Company's new multimillion dollar, 10,000,000 barrel per year cement plant went into full operation in February, 1962, bringing into reality a new concept in the distribution of Portland cement. The Cerro and Newmont Mining Corporations, well established in the mineral extraction and dressing industry, backed the venture. To take advantage of the, economics inherent in single production units of large capacity, it was necessary to first find a market' capable of absorbing such large quantities. Cement can be economically shipped by rail and truck about 200 miles. Beyond' that radius from the producing facility the freight costs become prohibitive. No single marker area within that radius exists which could absorb such a large volume of cement. However, water transportation provides a relatively inexpensive method of transporting bulk products many times over such a distance. Thus, it was decided to locate the producing facility near a deep water port which had ready access both to the Atlantic Ocean and, just as important, a good source of raw material. An extensive feasibility study was made and the site at Ravena, New York on the Hudson River near Albany was chosen. Here, vast quantities of limestone in the foothills of the Catskill Mountains are found within a short distance of-the deep-water Hudson River.

Jan 1, 1964

By Bernd Hagenah, Eric C. Wang

New tunnels of significant alignment lengths such as mountain tunnels, base tunnels, as well as beneath urban centers pose unique environmental challenges. This paper highlights key environmental considerations for planning, design, construction, and operations by sharing lessons-learned from the authors' extensive project experience on these types of tunnels. Discussion of unique constraints include limited right-of- way, ventilation and emergency egress during the construction phase and revenue service, safety and security, and protection of existing structures. Practical approaches and applied innovative state-of-the-art solutions addressing distinct sustainability challenges and unique requirements are shared from US and international project examples.

Jun 23, 2024

By Verya Nasri, Kevin Akbarpour, Hiva Mahdavi

"The Sheppard East Light Rail Transit (SELRT) project comprises approximately 13 km of new light rail, which will be constructed along Sheppard Avenue East in Toronto. There is a 380 metre long section of the route that will be constructed as tunnel below Highway 404, which is owned by the Ministry of Transportation Ontario (MTO). MTO has published guidelines for tunneling under its highways. An impact analysis was undertaken to predict the surface settlement and angular distortion of Highway 404 resulting from the construction of the twin tunnels. The results were then compared to the performance criteria defined in MTO’s guidelines. As a result of this analysis, it was necessary to request an adjustment to MTO’s current performance criteria. This paper presents details and results of the impact assessment, approaches taken to satisfy the requirements defined by MTO, and provides details of the adjustment permitted by MTO. INTRODUCTION Several major rapid transit projects are planned for the Greater Toronto and Hamilton Area (GTHA) located in southern Ontario, Canada. These projects are part of The Big Move (Metrolinx 2008) initiative, a 25-year, and $50 billion plan aimed at improving regional transportation. Metrolinx, an agency of the Government of Ontario, is now working collaboratively across the region to deliver major Toronto rapid transit projects to the GTHA. One such project is the SELRT. The line will largely run along Sheppard Avenue East on the surface, except for a crossing of Highway 404 where it will be constructed using a combination of open cut and bored tunneling methods. AECOM has been retained by Metrolinx as the Technical Advisor (TA) to develop the Reference Conceptual Design (RCD) and Project Specific Output Specifications (PSOS) for the project. Also, Infrastructure Ontario (IO) is the Co-Sponsor and CH2M HILL is Metrolinx’s Owner’s Engineer (OE) & Project Management Support (PMS) for the new LRT lines. This paper presents information on the tunneling settlement analysis and further work undertaken to satisfy the MTO’s requirements."

Jan 1, 2016

By Gail L. Achterman

Most mining companies today perform site assessments and operational or compliance audits regularly. The purpose of these audits is to review company facilities and operations to determine whether they comply with applicable federal, state and local environmental laws and regulations. Why Audit? Companies adopt assessment and audit programs for legal and business reasons. The business reasons include: (1) ensuring efficient and cost-effective compliance through early problem identification and resolution; (2) planning and implementing business transactions such as real estate conveyances, loans, mergers and acquisitions, and waste disposal service contracts; and (3) employee training and relations. Legal reasons for audits include: (1) avoiding enforcement actions and penalties; (2) meeting environmental permit certification requirements; (3) avoiding corporate officer liability; and (4) meeting Security and Exchange Commission disclosure requirements. The Environmental Protection Agency ("EPA") encourages environmental auditing by regulated entities. The EPA Environmental Auditing Policy Statement was published in the Federal Register on July 9, 1986 (51 Fed Reg 25,004). Although the existence of an auditing program does not create a defense to or otherwise limit a company's regulatory responsibilities, EPA considers compliance programs in setting inspection and enforcement priorities. If a company makes an honest effort to identify and correct its own problems, EPA's enforcement approach is influenced, especially if violations are promptly reported. Perhaps more significant to many executives, the U.S. Department of Justice issued guidelines last year on when it will pursue criminal prosecution for environmental violations. See Department of Justice, "Factors and Decisions on Criminal Prosecutions for Environmental Violations in the Context of Significant Voluntary Compliance or Disclosure Efforts by the Violator," (July 1, 1991). It is now commonplace to read about major companies pleading guilty to criminal violations and paying millions of dollars in penalties. For example ALCOA recently agreed to pay criminal fines and civil penalties totaling $7.5 million for unauthorized excavation of PCB-contaminated soil and improper dumping of spent caustic solution. No executive wants to explain to the Board of Directors or shareholders why the company was criminally indicted. The Department of Justice considers factors such as voluntary disclosure, preventive measures and compliance programs, such as a regular compliance auditing program, the effectiveness of the disciplinary system for employees who violate the company's environmental policies, and subsequent compliance efforts by companies to remedy ongoing noncompliance. The Department of Justice looks closely at whether audit recommendations were implemented in a timely way and whether environmental compliance was a standard by which employees were judged. The Lawyer's Role. The role of the lawyer in an audit team deserves special attention. When enforcement action or litigation has begun or is contemplated or a government agency has asked for information, attorneys always should be directly involved in environmental audits. In most situations, however, environmental audits are management tools, and the attorney's role should be to advise the team. The attorney can help make sure the team understands the laws and regulations the facility must

Jan 1, 1992

By Richard R. Klimpel

In this paper, the old and the new commercially available reagent chemistries for the improved flotation of sulfide minerals will be summarized. The reagent classes discussed are those that meet three criteria: 1) they are being commercially used and/or large scale plant tested in North America in the last few years; 2) they are clearly different in chemical structure than commonly used commercial reagents of the last few decades and are not simply mixtures of existing reagents and/or simple changes in cation, alkyl group size, etc. and 3) the structural formulae are clearly specified in the public literature.

Jan 1, 1994

By M. Galetakis

This paper proposes a new approach for calibration of dual gamma-energy transmission (DU-ET) ash analyser for improved online analysis of run-of-mine lignite. An adaptive neuro-fuzzy inference system (ANFIS) was developed to model the relationship between the intensities measured by the scintillation counter of the analyzer and the measured ash. Samples collected from Megalopolis lignite mines were measured for their ash content by using standard laboratory methods as well as by DUET. Obtained data was divided into training, testing and validation sets. A first order Sugeno type ANFIS was used in conjunction with early stop training. The calibration performance obtained by this approach was significantly better compared with that obtained by standard calibration methods based on multiple linear regression analysis.

Jan 1, 2006

By R. R. Klimpel

In three recent publications, Klimpel et al (1988) and Klimpel and Hansen (1988, 89), the theory and invention process behind the identification of two new classes of sulfide mineral collectors were summarized. These two new families can be represented by the 111 generalized formulate: R1-S-R1 -NRI III (denoted as the F-series chelation family) and R-S-R or R -CHSCH-R (denoted as the S-series redox family). The influence of systematic changes in the various R groupings on laboratory batch flotation cell tests has been covered in the above references and will not be repeated in this paper. In particular, the recent article by Klimpel and Hansen (1989) should be studied as a research introduction to this paper.

Jan 1, 1989

By Henning Schwarz, Faisal Al Arifi, Anas Almousa

"The Riyadh Metro Project forms part of a complete new public transport system integrated in the urban planning and development of the fast growing capital city of the Kingdom of Saudi Arabia. The Design & Build project consists of 176 km of a new metro network with 57 km of double track single tunnel infrastructures, spread over six metro lines. During the design phase, geological, hydrogeological, geotechnical and geophysical site investigations were undertaken to chart the, previously uncharted, underground construction space. Different TBM solutions were selected for implementation taking due consideration of the ground conditions of each metro line. The results obtained from deep excavations for underground stations and analysis of the TBM tunneling data will be used as key input for future tunneling projects in the Riyadh and the Kingdom of Saudi Arabia. The present paper details the design conditions and presents the solutions for large diameter tunnels in karstic limestone. INTRODUCTION The High Commission for the Development of Arriyadh was established in 1974 as the organizational, planning, executive and coordinating body responsible for the development of Riyadh. Arriyadh Development Authority (ADA), established in 1983, is the High Commission’s executive, technical and administrative arm. The ADA is responsible for implementing the High Commission's organizational, planning, executive and coordinating decisions and missions (ADA 2015). One of the remits of the ADA is the preparation and execution of a transport plan for the city. The metro network is planned to be the backbone of the public transport system developed as part of the King Abdulaziz Project for Riyadh Public Transport in Riyadh. With six lines and a total length of 176.5 km (Table 1) and 85 metro stations, the metro network will cover most of the densely populated areas, public facilities, and the educational, commercial and medical institutions. The network will connect the King Khalid International Airport, the King Abdullah Financial District, main universities, Riyadh downtown and the public transport center. The public transport plan includes a future bus network with 22 lines on 1200 km and 6765 stops that will be the main feeder for the Riyadh metro network; it will also be the main mode of transportation within and around Riyadh districts (ADA 2015)."

Jan 1, 2016