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By K. Oraee

A comprehensive, harmonic and sustainable development has always been a real concern of state policy makers. To reach such development, regional planning is an approach which is widely applied. This paper deals with policies adopted by a given country with rich mineral deposits, in order to accomplish a mining growth as well as economic development in relatively poor regions. In this regards, first, some worldwide experiences belonging to China, with large scale mining operations and Nigeria with a small scale mining industry, are studied. The mining industry in Iran is then considered as a case study. The study continues by categorizing and prioritizing Iranian regions based on their mining potential and the degree of development, using statistical analysis and Taxonomy and AHP techniques. Results obtained serve to provide recommendations as to where capital investments in the mining industry would produce highest returns. The approach used, together with the practical policies suggested in this paper, can be used to adapt appropriate strategies for mining development in a way that contributes to regional development and a more effective income distribution.

Jan 1, 2012

By Brian H. Greene

The U.S. Army Corps of Engineers, Pittsburgh District, is in the final phases of modernizing the locks and dams on the Monongahela River. One facet of this modernization is to replace the existing Locks 4 located on the Monongahela River approximately 40 river miles upstream from Pittsburgh, Pennsylvania. The existing locks consist of a 56-foot x 720-foot main chamber and a riverside 56-foot x 360-foot auxiliary chamber built in the 1930s. Two new lock chambers, each 84-foot wide by 720-foot long, will be constructed at the location of existing Locks 4 and will be named Charleroi Locks. The purpose of the new project is to facilitate navigation on the lower Monongahela River. Pittsburgh is currently the second largest inland waterway port in the nation, and the new locks will be an important component of the navigational infrastructure. The existing lock walls are of mass concrete construction and are founded on wooden timber piles driven to rock through alluvial sands and gravels. The new lock walls were designed to be supported by approximately 300 reinforced concrete drilled shafts, varying in diameter from 4 to 6 feet. To handle axial loads, the drilled shafts were designed for end bearing, with some skin friction. The tips of the shafts will be founded within competent rock. Since the walls will undergo lateral loads, the drilled shaft design also had to consider this loading condition. Some of the drilled shafts will be installed within coffer boxes, which will incorporate a tremie concrete seal down to top of rock. Complicating the design even further was the fact that some portions of the new walls will be supported by shafts that extend some 9 feet above top of rock through alluvial soils, producing a cantilever effect. The first phase of the new lock construction was initiated in the summer of 2005 with a contract awarded to replace the river wall. This required shutting down the existing riverside lock chamber and diverting all river traffic to the longer existing land chamber. The foundation of the new river wall will use 144 drilled shafts. To optimize the design embedment of drilled shafts in rock for the river wall, an exploratory drilling program was conducted by the contractor in July and August, 2005. Based on the quality of the sedimentary bedrock, the shafts will be embedded in rock from 31 to 38 feet. To achieve adequate end bearing resistance, the tips of each shaft will extend through predominantly claystones into a more competent siltstone unit for a minimum embedment of one foot. The contractor also performed an exploratory pile driving program to aid in the construction of the drilled shaft casing and the cut off walls that will encapsulate the river wall. Two demonstration drilled shafts located outside the footprint of the new river wall, will be constructed prior to the drilling of any production shafts. The demonstration drilled shafts will verify that the contractor is able to meet the design criteria and quality requirements of the contract. The river wall contract is currently underway and is scheduled to be completed in 2010.

Jan 1, 2006

By Michael S. Miller

In 1984, at the request of Bureau of Land Management, the Bureau of Mines studied 8,500 acres of the 20,250-acre Seven Blackfoot Wilderness Study Area (WSA) consisting of all 3,950 acres of MT-024-657A and 4,550 acres of the 4,850 acre MT-024-657B in order to evaluate the mineral resources. Within this report these 8,500 acres are referred to as the study area. Located about 30 miles northwest of Jordan, MT, the study area is underlain by outcrops of Quaternary alluvium and Cretaceous to Paleocene sandstones, shales, clays, and coal. No mines or prospects were found in the study area. Except for some current interest in petroleum and natural gas, there has been no mineral exploration activity in the study area. The study area contains subeconomic clay, placer gold, and coal. Land within the study area is leased or under lease application for oil and gas.

Jan 1, 1986

By A M. Hagni

Certain copper ores from the Nchanga Copper Mine in the northern Zambia Copperbelt are refractory with respect to conventional beneficiation techniques. This paper reviews recent study of those ores to determine their mineralogy, textures and nature of copper occurrence. Two suites of refractory ores were selected for study: 1.  samples of stockpiled ores from an open pit, and 2.  drill core samples from copper ores. Both sample suites are from the upper orebody at Nchanga and contain about 0.3 - 1.4 per cent copper as determined by atomic absorption, but they represent separate stratigraphic, mineralogical and beneficiation problems. Ore microscopic examination showed that fine-grained copper sulfides are totally lacking from both suites of refractory ores. Petrographic study found malachite in the refractory ores from the open pit, but that malachite probably is post-mine. The opaque mineralogy of the open pit refractory ores is dominated by goethite that occurs mostly as pseudomorphic grains after pyritohedral pyrite crystals that average 200 - 250 ¦m across. Haematite occurs as bands within or as outer shells of the goethite grains. Additional goethite occurs locally as finer-grained areas of exotic goethite. The opaque minerals in the drill core refractory ores are dominated by euhedral ilmenite crystals about 50 - 175 ¦m long. Anatase is the dominant opaque mineral in some drill core samples where it is largely pseudomorphic after ilmenite crystals. Goethite accompanies malachite in unusual drill core refractory ores that have experienced intense hydrothermal alteration. Thus, ore microscopy and petrography showed that fine-grained chalcopyrite and bornite and pre-mine malachite were not the causes of the refractory nature of the ores studied. Electron microprobe revealed that most of the copper occurred in solid solution within micas. Application of automated SEM techniques has provided a detailed understanding of the distribution of copper in these refractory ores.

Jan 1, 2008

By O. F. Brown

The use of quality materials (aggregates and asphalt binder) in optimal proportions is the key to producing optimally performing hot mix asphalt (HMA). The Superpave mix design standard in the US introduced specific volumetric and binder property requirements in HMA design. Different methods for HMA constituent proportioning have been proposed in various guidelines. The design process to determine the HMA blend is currently iterative and engineers rely almost exclusively on experience. This approach is time consuming and often does not result in cost-optimal HMA mixtures. This paper introduces a mixed integer linear programming (MILP) optimization model for hot-mix asphalt constituent proportioning. The MILP model minimizes the total mix cost while satisfying all the volumetric, binder and mix property specification requirements. The model has been successfully validated with real-life example. The aggregates and binder ratios from the model were in close agreement with those from the contractor. The Bailey ratios and the gradation constraints were also satisfied. The cost of the optimal mix was $0.804/Mg less than that of the contractors?. This marginal reduction might make all the difference in an industry that is highly competitive. The MILP model also demonstrated that adding RAP to the contractor?s design would reduce the cost of the blend by $5.74/Mg. The virgin binder content was reduced by 1% because of the recycled asphalt contained in the RAP. This work represents the first successful attempt in incorporating both aggregate and asphalt performance requirements into the optimization formulation. Applying these models will ensure the minimum cost mix that meets all constraints and will increase profit margins for plant operators.

Jan 1, 2012

Martin Marietta Aluminum, Inc. followed Howmet Aluminum Corp., Revere Copper and Brass, Inc. and Anaconda Co. in lifting August prices of 99.5 percent unalloyed aluminum ingot by 3 cents to 56 cents per pound. Prior to these moves, Kaiser Aluminum and Chemical Corp. raised its June ingot listings by 4 cents to 57 cents and Consolidated Aluminum Corp., 4.5 cents to 57.5 cents. Domestic merchants increased July quotes by slightly more than 1 cent to 51.3-51.8 cents per pound. ARSENIC The Occupational Safety and Health Administration (OSHA) issued new standards, effective August 1, for worker exposure to inorganic arsenic, a toxic substance linked by OSHA to lung and lymphatic cancer. The new standard will limit worker exposure to 10 micrograms per cubic meter of air over an 8-hour period, a drastic reduction from the previous standard of 500 micrograms for a like period. Implementation of the new standards may be the most difficult and costly for copper smelters where arsenic is associated with the copper feed material but problems will also be encountered by producers of arsenic containing products such as for pesticides and herbicides. The new standards allow use of personal protective gear for workers as an interim measure until plant engineering controls can be put into effect.

Jan 1, 1978

By Sune Eriksson, Stig Peterssonsune, Christer Fridfeldt

"Boliden Metal Corporation has developed a technique to treat complex copper concentrates containing large amounts of lead, zinc, arsenic, antimony and bismuth which cannot be treated in conventional smelters due to the impurities.Tests were carried out to treat such complex copper concentrates in the TBRC. They were performed in a pilot-plant TBRC with charges of 5 tons. These tests resulted in a new method to treat complex copper raw materials and produce a blister copper low in impurities. The background and data from the test work are presented as well as a flowsheet for a full-scale process.IntroductionThe Ronnskar Works is situated on the coast of the Gulf of Bothnia, 40 miles east of the Boliden Mine. Smelting began at Ronnskar in 1930 to process the complex ore extracted from the Boliden Mine. The Ronnskar Works has subsequently developed into a relatively integrated smelting plant.Copper and lead sulphide concentrates from Boliden's own mines as well as purchased copper raw materials are processed. The main products are refined copper and lead, but full utilization of the raw material also yields other metals and some metallurgical and chemical by-products. The products include gold, silver, zinc clinker, white arsenic, arsenic salts and arsenic metal , selenium and selenium compounds, nickel sulphates, sulphuric acid and liquid sulphur dioxide."

Jan 1, 1981

By Corinne Boone

CO2e.com, LLC - launched in November 2000 - aims to be ?the global hub for carbon commerce.? CO2e.com is a subsidiary of the Cantor Fitzgerald Group, one of the world?s leading brokerage firms Recent Investor in CO2e ? Mitsui & Co. Alliance with Cantor Fitzgerald Environmental Brokerage Services Group (CFEBS) Offices in London, Toronto, Tokyo, New York, San Francisco, Los Angeles, Connecticut, Houston Primary Goals/Benefits of ET § Goals of Emissions Trading: ? Permit Industrial Growth/Expansion ? Promote Economic Efficiency and Flexibility in Meeting Air Pollution Standards § Benefits of Emissions Trading: ? Enhance Air Quality w/o Economic Stagnation ? Encourage Development of New Technology ? Foster Most Efficient Use of a Limited Resource -- Clean Air § Contributes to Sustainable Development and objectives of UNFCCC, Kyoto Protocol?.

Nov 1, 2002

By Oswaldo Carhuancho

El presente trabajo señala la filosofía de trabajo en equipo desarrollada en la mina Pierina, Lima. La política de trabajo se sustenta en el pensamiento de Barrick, donde las prácticas administrativas basadas en la seguridad, salud ocupacional y el medio ambiente repercuten en el beneficio de sus empleados, accionistas y las comunidades en las que opera. Por ello, la primera preocupación de la empresa debe ser el trabajador y no las máquinas, así como la labor de los jefes no se limita a una actitud paternalista, sino a una democrática, de forma que el empleado asume sus responsablidades con seguridad y eficiencia. Como consecuencia de ello, se redujeron la cantidad de hombres-accidentess, se elevó el costo de producción y se redujo, la cantidad de personas en la supervisión de operaciones mina.

Sep 13, 2001

By John L. Kaplin

The underground construction for the Phase I Combined Sewer Overflow(CSO) Project is on an impressive scale by any measure, appearing more so in a midsize city like Providence, RI. The Narragansett Bay Commission recently completed $350 mil-lion in construction to improve the water quality in Narragansett Bay. This project included a number of serious challenges, delays, and disputes. Looking back on this complex project completed within budget, it is hard to consider the work as anything other than a success. Along the way, this outcome did not always appear certain.

The ERMS Process was developed during four years of testwork by Austpac Gold NL to overcome the severe metallurgical problems of the ilmenite atWestport, in the South Island. These deposits have been known for about one hundred years. They were originally mined for gold, and only later attracted attention as a possible source of titanium minerals.   The resource is of world scale and may exceed 20 million tonnes of contained ilmenite. Similar deposits occur at Barrytown further south and together these areas would constitute an important opportunity for export-oriented mineral development, if a viable beneficiation technology were available. Further processing is essential, as the composition of the ilmenite is well below market specifications.

Jan 1, 1993

By Michel C. Frippel

This section of the Minerals Yearbook reviews the minerals industries of 45 countries: the 12 nations of the European Community (EC) (Belgium, Denmark/ Greenland, France, Germany, Greece, Ireland, Italy, Luxembourg, the Netherlands, Portugal, Spain, and the United Kingdom); 6 of the 7 nations of the European Free Trade Association (EFTA) (Austria, Finland, Iceland, Norway, Switzerland, and Sweden); Malta; the 11 Eastern European economies in transition (Albania, Bosnia and Hercegovina, Bulgaria, Croatia, Czechoslovakia, Hungary, Macedonia, Poland, Romania, Serbia and Montenegro, and Slovenia); and the countries of Central Eurasia (Armenia, Azerbaijan, Belarus, Estonia, Georgia, Kazakhstan, Kyrgystan, Latvia, Lithuania, Moldova, Russia, Tajikistan, Turkmenistan, Ukraine, and Uzbekistan).

Jan 1, 1994

By M. Mead, J. Dumouchel, W. Yule, J. Giroux

The QMM mineral sands of South East Madagascar contain approximately 1,900 million tonnes of mineable sand with a total heavy mineral (THM) content of roughly 4.5wt%. The QMM deposits are the world’s largest known reserves of 60% TiO2 ilmenite and also contain a small volume of zircon. The deposits are semi-continuous and homogenous and the mineralized sands are free flowing with minimal overburden, induration & slimes. These characteristics are favourable to dredge mining and allow the application of conventional wet gravity, electrostatic & magnetic separation to final products. A mature THM mineral suite of high valuable heavy minerals (VHM) content has enabled the development of a relatively simple separation process.

Jan 1, 2005

By Emmanuel Henry

Few industries are more challenged by technical, political and market uncertainty than the mineral industry. Technical uncertainty in mining projects concerns the volume and quality of the resource, the processing and metallurgical parameters, the production efficiency, etc. Political uncertainty can take diverse forms and includes possibilities of change in the taxation system, risk of expropriation and risk of social instability or war. Market uncertainty depends on the market structure of the commodity; price and demand volatilities are the most common sources of market uncertainty. Intensive feasibility studies including these uncertainties and risks are required before investing up to billions of dollars in the development of a new mine. Current feasibility studies are often based on a single (or very few) mean geological scenario and simplified price profiles along the life of the project. Yet, strategic decisions, for example, the level of investment in exploration and metallurgical studies, adoption of a flexible, but more costly, mine design and risk-sharing strategies are made at an early stage. Over the last twenty years, Real Option theory has emerged as a unifying framework enabling strategic planning under uncertainty (technical, political and market). Geological and market variances (second order statistics) are pivotal for proper uncertainty quantification. The present study explores the possible benefits of combining modern geostatistical tools and financial techniques for project management. More precisely, the following questions are examined: Is geological uncertainty really an issue? Can we combine geological and price uncertainties in a unifying Real Option framework? A simple example aimed at illustrating the concepts involved is presented.

May 1, 2003

By Charles B. Carpenter

For many years, studies of ground movement and subsidence accompanying subsurface mining operations have been part of the research program of the Bureau of Mines. Periodic observations by engineers of the Mining Division of the Bureau of man-built structures beneath which mining operations are conducted offer indisputable evidence of subsidence in the form of creeks in masonry structures and fractures and depressions in the surface of the earth. As the removal of subsurface rock and earth material by mining, especially by the room-and-pillar method, is equivalent to withdrawing some of the foundation of a building, subsidence of the formations above, the mining levels in certain areas is easily understood as a gravitational adjustment of the overlying earth formations.

Jan 1, 1940

By Charles B. Carpenter

For many years, studies of ground movement and subsidence accompanying subsurface mining operations have been part of the research program of the Bureau of Mines. Periodic observations by engineers of the Mining Division of the Bureau of man-built structures beneath which mining operations are conducted offer indisputable evidence of subsidence in the form of creeks in masonry structures and fractures and depressions in tie surface of the earth. As the removal of subsurface rock and earth material by mining, especially by the room-and-pillar method, is equivalent to withdrawing some of the foundation of a building, subsidence of the formations above, the mining levels in certain air-as is easily understood as a gravitational adjustment of the overlying earth formations.

Jan 1, 1940

By M. R. Samis

The great variability of mineral and energy prices has motivated some governments to incorporate a windfall profits tax into their mineral taxation regimes. Windfall profits taxes are a means for governments to capture additional mineral revenue when mineral prices are considered higher than some historic level. Governments need to be aware of the effects of such contingent taxes on the exploration, development and operating decisions of mining companies. Mining companies need to be able to calculate the full impact of windfall profits taxes on the economics of their projects. This paper examines the valuation of a multi-phase copper-gold project in the presence of a windfall profits tax. Real options Monte Carlo simulation is used to characterise the different exposures of the mine owner and of the government to the risky cash flow streams that they receive from the project. The results highlight that Monte Carlo simulation paired with the real option valuation method is able to account appropriately for the differing risk exposures, while the traditional discounted cash flow valuation model is not. Our key conclusion for governments and mining companies is that the impact of contingent tax and royalty terms can and should be assessed using advanced valuation techniques, and the results used to improve contract designs under the constraint of actual and perceived fiscal system stability.

Jan 1, 2007

By T Smith, J Hatley

With the increased focus on the need for more uranium mines, this paper presents the design process currently underway for the development of the Millennium deposit in northern Saskatchewan, Canada. This deposit, located 630 - 750 m below surface, will be accessed by two shafts and will be mined by blasthole stoping methods at less than 500 t/d. Mining grade will approximate two per cent U3O8 and mine life is expected to be six to seven years. The project is a joint venture between Cameco, AREVA and JCU. This paper discusses in detail methods used to predict worker radiation exposures, the methods used to monitor the work environment and procedures unique to the uranium industry necessary to minimise worker radiation exposures.

Jan 1, 2008

By Robert Hopler

Some few years ago, when the cruiser “Brooklyn” was passing through the fairway to the southwest of the Battery, the ship being fully equipped with stores, etc., and therefore at her maximum draft, she grounded quite heavily upon some obstruction, and received injuries which necessitated her docking at the Brooklyn navy yard, where extensive repairs had to be made on her damaged bottom.

Jan 1, 2007

By R J. Wood

Raise drilling (or raise boring) is not a new technology or methodology. The first raise drilling machine was developed by The Robbins Company (TRC) of the USA in 1962. TRC manufactured the first tunnel boring machine (TBM) in 1952 and Jim Robbins, the founder of the company wanted to ‘turn the TBM concept on its head’ so to speak.Many improvements have ensued in the 50 years since the first machine. Such improvements include advances in the drill rod and thread design, cutters and reaming heads. Raise boring would not have been possible without the development of the tungsten carbide insert cutters and there have been big advances in both the carbide technology and in the mechanical design of the cutters.Over time mines have developed deeper with a greater use of diesel equipment resulting in greater ventilation requirements. This in turn means larger and deeper ventilation shafts. There have also been improvements in directional drilling techniques. This all combines with the need and ability to construct larger shafts using the safe method of raise drilling. With suitable geotechnical conditions the RBR900VF is capable of drilling shafts to a diameter and depth of greater than 8 m and 2000 m respectively. Greater diameters are possible over shorter lengths with suitable ground conditions.The RBR900VF was designed and manufactured to specifications developed by Macmahon. This machine has the greatest thrust and torque capability of any machine in the world. It enables cutters to be more heavily loaded in the larger diameter heads and this is essential for efficient rock excavation. Additional features of the new machine include minimal manual handling to provide a safer working environment and higher strength steel for the drill rods providing additional safety margin.CITATION:Wood, R J, 2014. A revolution in raise boring – the development of the RBR900VF, in Proceedings 12th AusIMM Underground Operators’ Conference 2014 , pp 171–178 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Mar 24, 2014