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In order to analyze and quantify distinct environmental properties in the vicinity of sites, the Site-Specific Natural Resources Information System (SARIS) has been developed based on a Geographic Information System (GIS). SARIS is one of the fundamental databases of a collaborative research program aiming at the resource orientated analysis of metallic raw material flows with aluminum and copper serving as exemplary case studies. The spatial database incorporates all present production sites of ore extraction, refining and smelting. Environmental data for each location were derived from global digital survey data covering land cover, soils, morphology, climate, topography and population density. The main application of this database is the characterization of environmental safeguard objects, which may be affected by the activity of concern. This site-specific environmental impact assessment is used to determine the relevance of environmental issues based on the distribution pattern of sites in a global framework. The derived results are used to suggest a tailored indicator approach to measure progress and performance of industrial developments relative to the predetermined site-specific conditions.

Jan 1, 2003

By Abdullah Arik

The resource classification methodologies have always been a topic of research and debate. There are both traditional and Geostatistical methods used in practice. Because of the uniqueness of each ore deposit, it seems almost impossible to have a single industry-accepted norm for resource classification. Therefore, some practitioners have adapted the methodologies to suit the deposits they are working on, but many simply use the methods they are comfortable with. Another reason for the existence of varying classification methodologies is the lack of an easy and established way to measure the confidence in the estimates. Therefore, their classification becomes a subject of debate. In this paper, a new approach is offered to classify the resources using a "Resource Classification Index." The approach using this index takes into account the local variation, the spatial data configuration around the block being estimated, as well as the traditional distance measures. A case study for a gold deposit is presented to demonstrate how this new index can be used to classify the resources. The results from this approach are compared to those from two popular classification methodologies.

Jan 1, 2002

By M. L. Smith

The U.S. Bureau of Mines Cost Estimating System (CES) has been used for prefeasibility analysis and mine cost engineering since 1978. In the past, prefeasibility analysis with CES has involved the solution of regression equations. The new generation of CES uses an object-oriented expert system in a Windows? environment. Knowledge bases are structured around generic mine models which access shared knowledge bases for system design.

Jan 1, 1994

By J. R. Allen

Environmental laws and regulations have proliferated over the last two decades. 1/ Within the last year, Congress has dramatically expanded the scope of the Superfund program 2/ and has enacted significant new amendments to the Clean Water Act.3/ In addition, EPA has shown no signs of slackening the pace at which it promulgates new regulations to implement statutory programs. The agency projects that over the next few years it will issue approximately 275 new regulations under the statutes it implements. 4/

Jan 1, 1988

By Werner A. Ruemmele, Steven R. Wardwell

INTRODUCTION The first phase of the Los Angeles Metro Rail Project consists of 7.1 km (4.4 miles) of subway and stations running through downtown Los Angeles from Union Station to MacArthur Park. Shank-Ohbayashi has two of the tunnelling contracts on this initial phase: A-171 and A-146. Contract A-171, the Wilshire/Alvarado Line, involves tunnel construction beneath 7th Street from the 7th/Flower Station to the Wilshire/Alvarado Station. The project consists of the excavation and lining of 3000 m (9900 ft) of twin-bore, 6.7 m (22 ft) excavated diameter, 5.5 m (18 ft) finished diameter subway tunnels. Contract A-146, the 5th/Hill to 7th/Flower Tunnels, comprises 1220 m (4000 L.F.) of twin-bore tunnel identical in cross section to the tunnels in Contract A-171. The majority of the excavation on Contract A-171 is beneath city streets in a weak siltstone/claystone bedrock with cover varying between 10 m and 25 m (32 ft and 82 ft) to the street surface. Approaching the 7th/Flower Station some fine-grained alluvium is encountered. The tunnels on both contracts are excavated with an open face digger equipped shield. On Contract A-146 the tunnel alignment is a 305 m radius curve of approximately 550 m (1800 L.F.) length underneath several multi-storied buildings of various construction. Excavation is still ongoing on Contract A-146. The contractor's choice for initial tunnel support on both contracts is a system of precast concrete segments similar to what the contractor had used on 7 miles of tunnel in Phoenix, Arizona, for the Arizona Department of Highways.

Jan 1, 1989

By C. Roos

Tradicionalmente en la industria minera, el flujo principal del proceso funcional para la evaluación de recursos y reservas procede de geólogos que elaboran el modelo geológico, de allí a los geólogos que hacen la estimación de los recursos (los modeladores) quienes estiman los grados, y a los ingenieros de mina que desarrollan el diseño de la mina y su calendario. La interfaz entre estas tres disciplinas no está siempre exenta de baches. Las presunciones hechas durante una etapa del proceso no siempre son comunicadas a los demás, a pesar que la mayoría de las empresas mineras tienen procedimientos y protocolos establecidos para promover la comunicación a lo largo de las distintas disciplinas. Estos procedimientos no siempre logran su propósito debido a una variedad de razones que incluyen restricciones de tiempo, no tener disponible a las personas apropiadas, o a una falta de entendimiento de lo que las otras disciplinas requieren, y el proceso de traspaso puede degenerar en el envío de archivos a la siguiente disciplina en el flujo de proceso. Este artículo se ocupa de la interfaz entre la estimación del recurso y las disciplinas de la ingeniería de minas y el esquema de algunas de las presunciones comunes hechas al generar un modelo del recurso y los riesgos que los ingenieros podrían correr al elevar los grados de corte, optimizar calendarios o realizar predicciones. Los casos de estudio presentados se centran en depósitos de oro a cielo abierto, pero los conceptos deben ser aplicables a toda la industria. Aquí también proveemos un resumen de preguntas clave y recomendaciones.

Jan 1, 2014

By F. Dudouit, M. M. Mohkam, F. Renault

The Pannerdensch Kanaal Tunnel is part of Holland’s Betuweroute high speed freight railway project linking Rotterdam to inland of Europe. It comprises of twin tunnels, 1620 m long each, with 8.6 m inner diameter. The Tunnel alignment is situated mainly in sandy formations and under high hydrostatique pressure. The over burden cover varies from relatively high to very low, sometimes much smaller than the diameter. One of the special features of the Pannerdensch Kanaal Tunnel is that, over some 250 m, the twin tunnels are to be bored in a back?lled sandpit. Some 490 000cubic meter of sand has been placed and compacted by vibro-?otation to refill the sandpit. The tunneling machine is a 9.8 m slurry shield manufactured by Herrenknecht. Tunnel lining is precast concrete consisting of seven plus one key universal segments. Other than the special feature of boring through re?lled sand, constraints such a slow overburden while crossing under Pannerdensch Kanaal and some lagoons, as well as high liquifaction potential of sandy formations, render this job very unique of the type. Fine studies were conducted in heading’s stability. And, confinement pressures were determined considering different risks of liquefaction and blowout problems. Both tubes have been successfully bored. Several sections have been monitored. The results are quite interesting and in accordance with contract technical conditions.

Jan 1, 2003

By Jon Y. Kaneshiro, Gregory E. Korbin, Stephen J. Navin, Larry J. Stout

Sewage presently being discharged into the Tijuana River Valley pollutes the valley as well as the beaches in the South Bay of San Diego, making the beaches unusable nearly year round. The SBTO will convey flows down a 8.5 m (28 ft.) by 58 m (190 ft.) deep drop shaft, through a 3.35 m (11 ft.) by 5.8 km (3.6 mile) long tunnel, and up a 46 m by 2.7 m (150 ft. by 9 ft.) riser shaft connecting to a 1.5 km (0.95 mile) of seafloor pipeline and 1.2 km (0.76 mile) of diffusers on the ocean floor. The drop shaft will be sunk through 38 m (125 ft.) of saturated sands and gravels and 20 m (65 ft.) into the dense fine sands of the San Diego Formation. The tunnel liner has been designed as a five piece, single pass, gasketed, bolted, reinforced concrete liner designed to withstand an external head of 76 m (250 ft.) of water and internal operating head of up to 27 m (89 ft.) and to accommodate movement at the numerous fault crossings. The tunnel is contemplated to be driven with a state-of-the-art Earth Pressure Balance Machine (EPBM) or slurry shield machine through a wide range of conditions from clay to gravel with boulders.

Jan 1, 1995

By S. D. Morrison, J. L. Watson

It is well known that the density and viscosity of a mill pulp have optimum levels for grinding efficiency, and sophisticated control loops are employed to control pulp density in industry. However, these control loops rely on a number of plant measurements, and often the input data will not permit effective determination and control of the mill pulp density. The use of a single remote pulp density measurement has obvious advantages, and it is suggested and demonstrated for laboratory batch grinding that mill noise measurements can indicate the effective density of the mill pulp. In addition, the mill noise is shown to indicate the actual effective pulp viscosity in the mill and hence permit the identification of the dynamic rheological regime existing in the mill. It is demonstrated that mill noise increases with grind time and, at any given grind time, with increasing pulp density in the pseudoplastic range. This increase in mill noise level with pulp density is interpreted as indicating a decreasing pulp viscosity. The results show that the transition from dilatant to pseudoplastic conditions within the mill, with increasing pulp density, can be identified by this increase in mill noise. When the pseudoplastic pulp started to exhibit yield characteris- tics, the mill noise fell dramatically. The technique of mill noise analysis is then used to investigate the effect of a grinding additive on the batch grinding of two ores. With a magnetite ore, the additive was shown to increase the mill noise, and hence decrease the pulp viscosity, in the pseudoplastic region and to increase the effective grinding. The molybdenite ore, however, did not show significant noise level changes and did not show improved grinding efficiency.

Jan 1, 1987

By B. T. Dawson

In today's work world, constant changes are a fact of life. Downsizing and technological advances are two of the most prominent concerns for employers and employees alike. In this article, the author addresses some of the emotional consequences of these changes and offers a new, empowering perspective for coping with them.

Jan 1, 1998

By Bill Reid

Coal companies mining the seams in the Appalachian region appear to be optimistic. Although some older mines are closing, newer mines are expanding. Money is being spent on new equipment and research to increase mining productivity, as well as improve safety. Coal has been produced from the rich Appalachian seams for about 200 years with no end in sight. Many equipment manufacturers have substantial backlogs of orders for new equipment. Some of the innovations being monitored by the Appalachian underground coal operators include au¬tomated longwall mining, continuous haulage systems and methane drainage. Appalachian coal was a major ingredient in the steel that culminated in the Golden Spike ceremony at Promontary Point, UT, where the final link in the transcontinental railroad was closed. This occurred on May 10, 1869, according to a history published by Union Pacific Coal Co. It stated that "rails and fastenings for track construction were purchased in Danville, Scranton, and Johnstown, PA and Troy, NY." Ever since, coal from the eight Appalachian states has contributed in no small measure to geographic expansion and economic growth of the United States.

Jan 1, 1995

By Siddhartha Agarwal

The mining industry collects a significant amount of operational data. However, gleaning useful information from the terabytes of data is difficult, and not just because of the sheer volume of the data. Therefore, an automated tool was developed at the University of Alaska Fairbanks to go through data and apply sophisticated statistical and neural network techniques in order to identify the data streams that are important to a process. This paper presents results from the tool as applied to SAG mill data from a gold mine. The results were compared to results achieved earlier with available commercial modeling tools. The comparison indicates that there was little or no loss in performance by automating the very complicated process of neural network modeling. Therefore, the intent of the exercise, to examine if complicated modeling tasks can be automated, was realized. Mining Engineering, 2011, Vol. 63, No. 12, pp. 52-54. Official publication of the Society for mining, metallurgy and exploration, Inc.

Jan 1, 2011

In 1989, United States mine production of barite decreased 13% while world mine production decreased by 8.6%, according to the US Bureau of Mines. Consumption, sold or used by grinding plants, decreased by 21.2%. And imports decreased by 12.8%. The value of domestically produced barite, fob mine, increased 17.4%, according to the Bureau. The declared value cif US port of all imported crude barite during 1989 increased from $38.10/t ($34.56 per st) in 1988 to $40.27/t($36.54 per st). Nevada continued to be the leading producer of barite with 77% of the total, followed by Georgia and Missouri. The Bureau of Mines estimates 75% of the domestic mine production was used as a weighting agent in drilling fluids. The remaining 25% was used in barium chemicals, glass, or as a filler. Most of the production from Missouri, Georgia, and Tennessee was used in the nonoilfield sector. Of the total consumption used by grinding plants and chemical manufacturers, it is estimated that 80% was used in drilling fluids. The other 20% was used in the non-oilfield sector, including barium chemicals and fillers in paper, plastics, and glass. The tonnage consumed in the drilling fluids market decreased due to the lower average rig count during 1989. The average number of rotary rigs operating was 869, 7.2% less than the average of 936 in 1988. Crude barite imports were down 12.8% from 1988. Imports accounted for 73.8% of the barite consumed (apparent) in the US. China continued to be the leading exporter of crude barite ore to the United States with 63% of total crude ore imports. India followed with 27.4%, Peru 4.3%, Chile 2.9%, and Canada and Mexico, each with 1.1 %. About 97% of the imported barite ore was used in the oilfield sector.

Jan 1, 1990

By P. G. Semple, K. W. Major, P. Eng.

The recent increase in development of refractory gold deposits has resulted in changes to the traditional treatment processes. The selection of the preferred refractory treatment process is dependent on the mineralogy of the ore. One process, which has recently gained increasing attention, utilizes dry grinding and roasting of the whole ore. This paper will discuss some of the considerations to be addressed during the design of the process fl owsheet and what the effects of the various alternatives will be on the plant capital and operating costs. The paper will be based, in part, on current experiences with dry grinding, roasting plant design and start-up.

Jan 1, 1990

By J. M. Link

A technique is presented for the economic selection of a slurry pipeline with the aid of a computer. Mathematical models for the flows of homogeneous slurries are utilized. Only the pipeline and its prime movers are considered. Slurry flow properties are first obtained from rheology and/or pipeline data measurements. A rheological model is then selected for the slurry. It must be emphasized that the accuracy of the method is greatly affected by the accuracy of the slurry flow-property data. Approximate cost parameters may be selected from data for plain and lined pipes, centrifugal and positive displacement pumps, motors and engines. Cost data for the purchase, operation and maintenance of slurry pipelines are also described. A total cost equation for the ownership and operation of a slurry pipeline system is then established. The complexity of the equation is a function of the rheological model selected to describe the slurry. The equation is solved with the aid of a computer for several combinations of pipeline diameters and throughputs to yield minimum total annual cost for the system. A mean velocity is then computed to give the required throughput. The velocity is constrained by an upper and lower bound. A high velocity is undesirable from an energy consumption viewpoint and if pipeline wear is possible. On the other hand, the velocity must exceed the deposition velocity for a heterogeneous suspension or the critical velocity for a homogeneous suspension. There is no guarantee that the velocity developed by this method will lie within the constraints applied, nor that the constraints are even known. This is particularly true for heterogeneous slurries. An important feature of the method is the ease with which the variables can be adjusted to measure the sensitivity of the total cost to the variables. The purpose of the sensitivity analysis is to identify those critical variables that. if changed, can considerably affect the total cost. Mathematically, individual variables are changed and the effect of such a change on the annual total cost is computed. But from a designer's point of view, individual components in the system are changed to study their effect on the annual total cost. A change in one component of the system may involve a change in one or more variables. For example, the replacement of a steel pipe by a smooth-lined pipe will change the pipewall roughness and wall thickness as well as purchase, operating, and maintenance costs.

Jan 1, 1974

By T. W. Flemal

Good afternoon gentlemen. To begin, may I say ?thank you? to the AIME for the invitation to be here today to talk about my company's experience with shovel, truck, pocket, to car loading. The other author of this paper is here today. (Introduce John Sweet). Before we get to the details of this paper I want to tell you a little about Erie Mining Company. Erie Mining Company is located on the east end of the Mesabi Range in northern Minnesota and is engaged in the business of processing taconite rock into iron ore pellets. In 1970, the twelfth year of production, Erie will produce its rated capacity of 10.3 million tons of high grade iron ore pellets. The plant is the first of five iron ore pelletizing operations managed by Pickands Mather & Co. with a combined annual production capacity of 21 million tons. This plant began producing high grade iron ore pellets in 1957 placing it among the earliest of taconite production facilities in North America. Historically Pickands Mather & Co. had been a leading natural ore mine managing firm in the Great Lakes region for more than 70 years. Pickands Mather & Co. moved into the new field of taconite mining and processing with management and operational experience from the open pits and underground mines. We were to learn much of volume taconite handling requiring new equipment and new procedures. A trial and error period through the early years of taconite processing developed through the operation of an experimental sized preliminary plant near the present Erie Mining Company site.

Jan 1, 1970

By Faruk Oksuz, Dave Schiemann, Matt Trotter, Mike Padilla, Miguel Sanchez, Carmen Scalise

"Chicago’s Tunnel and Reservoir Plan (TARP) is a nearly $4.0 billion and over 30 years long program and arguably the largest and longest combined sewer tunnel and reservoir system in the world. Recently, a massive tunnel construction is underway for connection of the McCook Reservoir to the existing TARP tunnel system. Once completed in two stages in 2017 and 2019, the reservoir will hold 38 billion-liters (10 billion-gallons) of combined sewer overflows (CSO) and flood waters from the city of Chicago and over 20 communities in Cook County, Illinois. McCook Main Tunnel will connect Chicago TARP’s Mainstream Tunnel to the McCook Reservoir. Connecting two 10-meter (33-ft) diameter tunnels at 92 meters (300 feet) underground has not been a simple task for the McCook Tunnel Project participants, the project owner U.S. Army Corps of Engineers (USACE), local sponsor Metropolitan Water Reclamation District (MWRD) of Greater Chicago, designer Black & Veatch, and the contractor, Kiewit Infrastructure Company (Kiewit). Yet alone excavating and lining massive size tunnels, the team is also challenged with live tunnel conditions in TARP Mainstream Tunnel that carries CSO and flood flows from city of Chicago which runs full during rain events and must remain in service at all times. The project is a noteworthy feat for engineering and construction with the upcoming installation of world’s largest underground wheel gates for flow control within the tunnel. In this paper, we describe one of its kind elements of this major tunnel system along with key design and construction considerations, specifically for the live tunnel connection which is a rare occurrence in the tunneling industry. INTRODUCTION The McCook Main Tunnel system consists of a 10 m (33 ft) finished diameter and 490 m (1,600 ft) long hard rock tunnel constructed from a 27.5 m (90 ft) diameter and 92 m (300 ft) deep main gate and tunnel construction access shaft. The gate shaft houses six high head 4.4 m by 9 m (14.5 ft by 29.5 ft) wheel gates to be installed in the bifurcated and steel lined section of the tunnel. The tunnel also includes portal and energy dissipation structures as it daylights into the reservoir."

Jan 1, 2016

By S. M. Moore, J. F. Burr, R. Fernando, D. Snyder

"The Mine Improvement and New Emergency Response Act of 2006 (MINER Act Public Law 109-236) was passed by Congress in response to three major underground coal mine accidents in the United States that claimed the lives of 19 miners. The Act resulted in substantial changes in the underground coal industry relative to the use of technology for mine escape, rescue, disaster response and other areas where the lack of these technologies contributed to the fatalities caused by these tragedies. This year marks the 10th anniversary of the MINER Act, which makes it an opportune time to reflect on the events that led to its passage, the changes that have been made since then, and the work that remains to be done. As discussed below, the last decade has demonstrated tremendous cooperative efforts among mining operators, technology innovators, labor, The National Institute for Occupational Safety and Health (NIOSH), the U.S. Mine Safety and Health Administration (MSHA) and state regulators, resulting in substantial improvement of the technologies used for escape and rescue and noteworthy progress toward meeting many of the goals of the MINER Act. While the MINER Act and this article pertain primarily to coal mining, many of the technologies are equally applicable to any underground mining and have already found some acceptance outside of coal. TECHNOLOGY GAPS TARGETED BY THE MINER ACT The MINER Act addressed several technology challenges: • Problems with donning and switching between self-contained self-rescuers (SCSRs). • Poor visibility in smoke. • No wayfinding assistance for escape from the mine. • Limited breathable air supply. • Inability to locate trapped miners. • Inability to communicate with trapped miners. • Failure of mine seals. The MINER Act had several provisions that prescribed specific safety technologies intended to address these issues. Many of these were directed at post-accident technology requirements — an area in which Congress mandated additional technology investment. Specifically, the Act required mine operators to submit emergency response plans (ERPs) that contained provisions for implementing new or improved post-accident communications, tracking, lifelines, refuge alternatives and breathable air supplies along with training for emergency procedures and local coordination of emergency response. Most of the requirements were to be carried out within three years of the ratification of the MINER Act. In addition to these requirements for mine operators, the Act clarified and expanded NIOSH’s role and authority in enhancing the development of new mine safety technologies and expediting their commercial availability. The MINER Act also required NIOSH to develop research on refuge chambers, mine seals and the use of belt air and fire-retardant belts. Mine seals had to be upgraded and MSHA turned to NIOSH for applied research to establish the new explosion-resistance requirements. Progress toward closing the gaps."

Jan 1, 2017

By Achille Balossi Restelli, Elena Rovetto, Andrea Pettinaroli

"The Station “C13” of Warsaw Underground Line II, with tunnel crown 10m below the water table, required the excavation of three connection tunnels, underpassing a six-lane in service road tunnel, working from two lateral shafts. After the collapse occurred while digging the first tunnel, the use of artificial ground freezing was chosen to ensure the excavation under safe conditions. A complex freezing pipe geometry and excavation sequencing was necessary because of the interferences of the overlying road tunnel diaphragm wall foundations, shaft internal structures and previous grouting activities. A combined freezing method was used: nitrogen for freezing the tunnel arches, brine for freezing the intermediate wall and for maintenance stages. Sandy and silty sandy layers were frozen around the crowns and sides. No treatment was necessary for the inverts, lying in clay. A monitoring system of ground temperatures and structure movements allowed for successful completion of work in 8 months. INTRODUCTION The C13 Station of the Warsaw Underground-Line II is located on the West bank of the Vistula River. It consists of two shafts and three connecting tunnels, passing under the Wislostrada (WS) Road tunnel. According to the initial geotechnical investigation, tunnels should have been excavated in high-plasticity clay, but during the first borings non cohesive soil was encountered. Additional investigations were performed on both shafts and a more detailed stratigraphy was reconstructed (Lombardi et al. 2015). Layers of fine sand, sandy silt and sandy silty clay were present along the tunnels crown arches and in the North East tunnel they extended down to the centre line (-13.735m above the Vistula River medium level). Based on the new stratigraphy, it was decided to stabilize the crown and control the groundwater inflow from the face with jet-grouting columns extending the treatment down to the clayey soil, but a collapse occurred in the North West tunnel with soil and water inflow inside the shaft."

Jan 1, 2016

By Marina K. Peshkova, Izabell V. Pomorova

Computer modelling system for definition optimal way of in- vestment under condition of diverse directions of activities mining enterprises has been created. The main purpose of paper is to introduce the new scientific approach of finding effective variants of investment for mining industry under free market condition in Russia, it can be also interesting for domestic and foreign investors.

Jan 1, 1996