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By Angel Rafael Fernandez, Yahya Khader Al-Harbi, Benjamin Cebrian Romo, Antonio Morato Medina

The kingdom of Saudi Arabia has set the goal to diversify their economy from oil into different fields including mining. As the vast Arabian Peninsula is explored, orebodies of Aluminium, Copper, Gold and Phosphates are found in high grades and tonnages. Hard rock is present in most of the projects and require high quality blasting in regard to ore dilution, wall control and fragmentation. Maaden Gold has currently 4 open pit mining operations 1 new opening and 2 underground. More projects are coming online in the next few months and years. A new generation of mining engineers need to apply drilling and blasting techniques that compete with modern and efficient open pit and underground mines.

Feb 6, 2023

Jan 1, 1970

By W. M. McKewan

This U.S. Bureau of Mines report discusses wire ropes used for hoisting in U.S. mines. The in-formation presented was extracted from a large body of data compiled by the U.S. Mine Safety and Health Administration (MSHA) using a data base management system (DMS). Further, these extracted data were then manipulated to provide tables of data that show the types and amount of wire rope used for hoisting. This report describes the different types of wire ropes and how a DMS can be used to manipulate MSHA's wire rope inventory data. The data indicate that more 1-1/4-in-diam ropes, 6x27 construction ropes, and right lang lay ropes are used in U.S. mines than ropes of any other diameter, construction, or lay type.

Jan 1, 1991

By Amitava Gangulee

A recent investigation has shown that solid solution hardening is almost absent in the quasibinary system SnTe-pbTe.1 The lack of solid solution hardening was attributed to the small difference of only about 3 pct between the atomic sizes of lead and tin, and to the fact that the formation of these solid solutions involved changes only in the sublattice occupied by the lead and tin atoms. The investigation reported here is concerned with the quasibinary system PbSe-PbTe which, similar to the SnTe-PbTe system, forms a continuous series of solid solutions2 and has the same NaC1-type (Bl) structure. The size difference between the selenium and tellurium atoms, however, is slightly larger than 7 pct. No indication of any ordering of the lead and tin atoms at. selected compositions had been found in the system SnTe-PbTe, which had been explained by the weak second-nearest-neighbor interactions between lead and tin atoms.' The possible occurrence of an ordering transition in the system PbSe-PbTe was also investigated in the present work. Polycrystalline specinlens of PbSel-1-xTex (x = 0, 0.20, 0.25, 0.33, 0.50, 0.67, 0.75, 0.80, and 1.0) were prepared by melting appropriate amounts of 99.999 pct pure Pb, Se, and Te j.n evacuated and sealed Vycor capsules. The capsules were quenched in water. The solidified ingots were homogenized at 800°C for 14 days. Chemical analysis of the homogenized ingots showed that the deviations from the stoichiometric compositions were less than 0.1 at. pct for each component. Part of each ingot was ground to pass through a 75 g sieve and pressed into 25.4 mm by 12.7 by 2 mm briquettes. Duplicate sets of specimens, each containing at least one briquette and part of the ingot of each composition, were sealed in evacuated Vycor capsules. Both sets were annealed at 500°C for 7 days; one set was quenced in ice-water and the other was cooled to room temperature over a period of 14 days.

Jan 1, 1970

By Ray J. Holmquist

"INTRODUCTION At the request of Elmer Burch, of Taos, N. Mex., the Apache mica mine was examined by an engineer of the Bureau of Mines in October 1942. As the result of this examination, the Bureau of Mines proposed to extend an adit to the projection of the mica-bearing dike. The Federal Geological Survey then prepared a topographic and geologic map of the property. This information and consultations with members of the Survey 3/ assisted in determining the course and extent of the exploratory work. The author supervised the work, which was done from January to May 1944.Title to the property was in litigation during the period of the Bureau of Mines investigation. Conrad Johnson, of La Madera, N. Mex., was contesting the valley of Burch's claim location covering the Apache mine. Johnson was a prior claimant. A map made during mining operations prior to 1929, showing all mine workings, was in the possession of Johnson, but he would not produce it for inspection as long as his title to the property was in doubt. The course of the adit extension was therefore controlled by the best information and judgment otherwise obtainable."

Mar 1, 1947

By Arthur D. FitzGerald

EDC established an Environmental Review Framework in 1999. Throughout the early fall of 2001, the Corporation held public consultations across Canada to strengthen that framework, leading to a public release on November 15, 2001 of a report summarising the results of these consultations. Following this, the Corporation implemented strengthened environmental review requirements in the form of its Environmental Review Directive, in compliance with legislated amendments to Canada?s Export Development Act that went into effect on December 21, 2001. Over the past few years, there has been a global trend towards an increase in the social and environmental requirements of multilateral/bilateral financial institutions and export credit agencies. More recently, this activity has focussed on capturing institutions that have not yet adopted similar requirements and, more specifically, on developing a convergence of the requirements from institution to institution. This paper describes EDC?s new ERD and some of the initiatives that have taken place or are in process that are moving international financial institutions toward converging their environmental and social requirements for projects in the private sector.

May 1, 2002

By Barbara S. Parrish, I. S. Parrish

For two consecutive years the author and his wife have been fortunate enough to have been invited by the Peoples Republic of China to work with Chinese geologists of the Geological Bureau of the Ministry of Metallurgical Industries (MMI). Our visits, each of which lasted 7-8 weeks, took us to northwestern Sichuan, central Anhui, and much of Hebei Province, as shown in the accompanying drawing. We were asked to evaluate, criticize, and offer suggestions on the exploration and mining techniques used by the Chinese. Our commission both years was centered on gold, although we were also to visit other operations when the opportunity arose. In 1986, the visit primarily concerned with disseminated "Carlin" type gold deposits; in 1987, with "Greenstone" type gold deposits. Gold has been targeted by the Chinese as a metal of importance to the nation. Several governmental agencies have received direction and budgets to seek and develop gold properties. Besides the Ministry of Metallurgical Industry, gold is being sought by the Ministry of Geology, the China Gold Corporation, and reportedly the Peoples Army. There is considerable competition among these agencies. It is not uncommon to find two or more agencies working in the same general area. However, communication between the groups is minimal. Last year, we toured a small mine at Bambishan. We could see a diamond drill across the valley. The rig belonged to another Ministry and my guides voiced their curiosity to know what their competitors were finding. Mining, too, is not the monolithic bureaucracy that most Westerners anticipate in China. There are various levels of mining. These differ not only in sophistication, but in ownership. First, for small deposits the state allows "Peoples Mines". These can be owned and worked by individuals. The individual owner-miner may hire relatives or neighbors and give them a wage or he may turn the mine into a joint ownership situation. They

Jan 7, 1988

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 J. W. Paul

A study of mining methods and underground practices as they influence injury from falls of roof or coal reveals data as to the location in the mine where such injuries occur with the greatest frequency and as to some of the methods and practices which are in use for the prevention of injury. This paper, which presents statistics bearing on the frequency and place of occurrence of accidents and discusses regulations and practices which have resulted in a low-frequency rates from falls of roof and coal in a few representative mines, takes its information from mine-accident reports and from the results of studies conducted in a group of 80 mines in the bituminous coal fields of Western Pennsylvania, Ohio, and West Virginia. The statistics from this group of mines cover periods of one to four years but average 2 years and 7 months. During this time these mines produced over 110,400,000 tons of coal, equivalent to one-fifth of the annual production of all bituminous mines in the United States. The coal beds of the mines in the group studied are mostly flat, with local pitches of moderate degree. A number of mining plans are in use, each of which follows a general system of multiple entries, gross entries, and rooms. Room and pillar in panels either advancing, retreating, or half advance and half retreat, and the block system are employed. The methods of pillar extraction are by splitting, slabbing, pocket-and-stump, and open end. It is hoped that in presenting some of the details of the methods and practices at particular mines of this group which have commendable records in the prevention of injury some goad may accrue to many other bituminous mines which have similar natural conditions.

Jan 1, 1933

By Pingchao Ke, Zhihong Liu

"To overcome the problem that scoroditeis not stable in neutral and alkaline solutions, we proposed and investigated a synthesis method of scorodite coated in-situ with hydrated ferric oxide in the Fe(II)-As(V)-H2O system at the initial Fe(III)/As(V) molar ratios larger than 1.0.The synthesis was carried out at 90?,pH 1.5 under atmospheric pressure. During the synthesis, oxygen gas was conducted and bubbled into the system to oxidize Fe(II) ions into Fe(III)ions, and Na2CO3aqueous solution as neutralizing agent was added controllably into the system for keeping the pH constant at 1.5. In this study, three samples of scorodite were synthesized at the controlled initial Fe(II)/As(V) molar ratios of 1.0, 2.0 and 3.0, respectively. The characterizations of the samples by HRTEM, TEM/EDX, and chemical composition indicated that the particle surfaces of scorodite synthesized at the initial Fe(II)/As(V) molar ratio of 2.0 and 3.0 were coated in situ by a film of hydrated ferric oxide with the thickness of several nanometers, while the sample synthesized at the initial Fe(II)/As(V) molar ratio of 1.0 was uncoated scorodite. The TCLP and long-term leaching for the toxicity characteristic of the samples showed that scorodite coated in situ with hydrated ferric oxide was stable in a wide pH range from 3.0 to 10.0, with the arsenic concentrations in the leaching solutions less than 1.0mg/L. Nevertheless, uncoated scorodite was unstable under the conditions from weak acidity to alkalinity, with the arsenic concentrations in the leaching solutions larger than 5.0 mg/L.INTRODUCTIONArsenic pollution is a challenge for environment and health and has been an important issue for scientists (Hopkin, 1989).Arsenicis commonly associated with ores or concentrates of nonferrous metals, mainly as independent arsenic bearing minerals such as arsenopyrite (FeAsS), tennantite(Cu12As4S13), enargite (Cu3AsS4), cobaltite (CoAsS), and gersdorffite (NiAsS), realgar (As2S2), orpiment(As2S3), etc.(Matschullat, 2000; Mandal & Suzuki, 2002; Long & Peng, 2012). In the nonferrous metallurgical processes, arsenic is enriched mainly in such arsenic bearing materials as various flue dusts, residues, and anode slimes, which results in the accumulation of arsenic in the system owing to the circulation of those arsenic-bearing materials back to the system and the pollution to the environment (Harris, et al, 2003).In addition, the utilization of arsenic is limited and has been decreasing owing to its toxicity and carcinogenicity. Therefore, arsenic has to be removed from those arsenic-bearing materials and discarded safely (Dutrizac & Jambor, 1988; Monhemius & Swash, 1999; Drahota & Fillippi, 2009).In this case, how to immobilize arsenic has become a difficult problem which must be solved. Among the methods of immobilizing arsenic which have been proposed and investigated, immobilizing arsenic into a stable mineral to fix it, has been realized as a promising method and becomes a research focus(Dutrizac et al, 1987; Dutrizac & Jambor, 1988; Demopoulos et al, 1995; Fujita et al, 2008a; 2008b).Scorodite has been known as one of the best minerals for immobilizing arsenic, owing to its high stability under weak acidic condition, the arsenic content as high as 32wt%,and good crystallinity benefiting the separation of solid to liquid(Daivid et al, 1999; Zhu & Merkel, 2001). Scorodite can be synthesized from arsenic containing solutions under both hydrothermal and atmospheric conditions, and a lot of work has been done on the synthesis of scorodite and its leaching stability characterization (Filippou & Demopoulos, 1999; Gomez et al, 2011).Two plants for the immobilization of arsenic as scorodite have been putin to operation in Chile and Japan, respectively (Filippou & Demopoulos, 1999; Amir et al, 2016)."

Jan 1, 2017

By S. D. Thompson

An AIME transaction by P.L. Allsman (1960), "Analysis of Explosive Action in Breaking Rock," contains many useful concepts applicable to blast design. Of special interest was the derivation of a heave blasting burden formula, which is important in establishing the maximum burden. Unfortunately, its derivation contains a fundamental error and then a compensating one. This formula was: [ ] The derivation used the impulse-momentum principle, with a 0.3 m thick (1 ft thick) radius of rock mass being acted on by an explosive impulse. However, the rock weight was not converted to mass by dividing by the gravitational constant. This mistake can be verified by checking the units in the formula, which resolve into m%-sec instead of meters. Adding the gravitational constant corrects this: [ ] If the minimum velocity is now taken as 0.3 m/sec (1 ft per sec), as was recommended, excessively large burdens result. Any appropriate rock velocity should be capable of throwing the rock mass a minimum distance so that the swell needed for breakage can occur. Unless the burden is extremely small and the bench height is very high, it is unlikely that a velocity of only 0.3 m/sec (1 ft per sec) will be sufficient. A review of the literature indicates that average rock velocities observed by camera studies typically range from 15 to 30 m/sec (50 to 100 ft per sec) (duPont deNemours and Co., 1977; Tansey, 1979). On this basis, a minimum rock velocity of about 15 m/sec (49 ft per sec) would be expected and not 0.3 m/sec (1 ft per sec). When a velocity of 15 m/sec (49 ft per sec) is inserted into the corrected formula, the results approximate those of the original formula with a velocity of 0.3 m/sec (1 ft per sec). The errors were approximately self-compensating [ ] References Allsman, P.L., 1960, "Analysis of Explosive Action in Breaking Rock," Transactions, AIME, Vol. 217, pp. 475-476. E. I. duPont deNemours and Co., 1977, Blasters' Handbook, 175th Anniversary Edition, Dupont, Wilmington, DE, pp. 233. Tansey, D.O., 1979, "The DuPont Sequential Blasting System," CIM Bulletin, Vol. 72, July, p. 80. Thompson, S.D., 1981, "Critical Review and Revision of Surface Blasting Practice," MS thesis, West Virginia University, pp. 308-316.

Jan 3, 1985

"Chairman: Mr W. S. GALLAGHERRapporteur: Professor A. M. STARFIELDPapers:Long-term mine production scheduling by G. C. S. BurneAn application of linear programming to investment analysis by A. ErlandssonOptimizing medium-term operational plans for a group of copper mines by M. Splaine, D. C. Atkinson, W. Davison and L. SmithThe simulation of underground stoping and transport operations in gold mining by F. H. Touwen and N. C. JoughinProduction planning is a subject that lies at the interface between the computing centre and mine management. Discus¬sion during this session was thus largely concerned, directly or indirectly, with communication between computing and mining personnel, and as such was relevant to the symposium as a whole.Mr A. Weiss set the tone of this discussion by referring to `user-orientated systems'. He congratulated Mr Burne in this regard, pointing out that his long-term production scheduling program, as a computer system, was similar in approach to the manual system it replaced, and was therefore easily understood by planning engineers. He asked whether the schedule engineer had his 'hands on' the system, to which Mr Burne replied that the engineer did in fact spend several days running alternative schemes through the computer. Mr Weiss commented on the advantage of having terminals on site for this sort of engineer-computer interaction. He also commented on the flexibility of Mr Burne's approach to scheduling and how preferable this was to a one-step optimization package. This was brought home by a question from Mr H. D. Small: Mr Burne's program sometimes found it necessary to temporarily halt an advancing face, and he asked whether the logic of the program could be altered to avoid this (e.g. by suitably slowing down the rate of face advance). Mr Burne replied that it was in fact easier for the planning engineer to sort this problem out manually. The way in which the computer results were presented made it particularly simple for the production engineer to see how to avoid or remedy a stopped face.On the technical side, both Mr Weiss and Mr H. M. Wells questioned Mr Burne on the handling of grade control by his program. From answers by Mr Burne and his colleague Mr K. H. Thomson it emerged that a spot-check on grade every now and then was all that was necessary at Mufulira, and that the idea of actual grade control was more a question of short-term than of long-term planning."

Jan 1, 2014

By A. S. Swanson

In view of the necessity or increasing production of metallurgical fluorspar to satisfy wartime demands, 0, M. Bishop, former district engineer of the Bureau of Mines, L. W. Carrier and. J. S. Williams, senior geologist of the Federal Geological Survey, and E. H. Dawson, mining engineer of the War Production Board made a joint survey of the Illinois-Kentucky fluorite district in July 1942 to determine what steps should be taken to increase production. As part of their recommendations, a program for exploring the idle Klondike mine in Livingston County, Ky., was outlined. All the ore produced at the Klondike mine was mined above the 325-foot level, where some tonnage remains. Factors that influenced selection of the Klondike mine for exploration were favorable geological conditions, the state of mine development and the availability of pumping equipment and some usable mine and mill equipment. In December 1942, the Metals Reserve Co. leased the Klondike mine from the Salem Fluorspar Co.

Jan 1, 1949

By John B. Knaebel, Robert J. Grant

This paper outlines the trends in gold production since the discovery of America, in the world as a whole, and in the principal producing regions as well. World production climbed at an average rate of about 20,000,000 oz. per 5-year period until the record all-time output of 111,307,000 oz. in the period ending with 1915. Production fell off during the war period, but has been mounting since 1925, and will probably be nearly 100,000,000 oz. for the 5-year period ending in 1930. Total world production of gold from 1492 to the end of 1930, as closely as can be determined, is more than 1,061,000,000 fine ounces. More than one-half of this total, or about 575,000,000 oz., has been mined since 1900. In percentage of world production, the United States jumped from 4.8 per cent for the decade 1831-1840 to 44.5 per cent for the five years ending with 1855. This is the highest figure ever reached by this country, although, with the exception of the 10-year period ending 1865, it ranked first among the nationa from 1849 until the end of 1905. During the 5-year period ending with that year, the United States produced 24.7 per cent of the world's gold. The tremendous increase from South Africa following 1890 resulted in that country's becoming the largest contributor for the five years 1906-1910, a position it has held with increasing dominance ever since. Relegated to second place in the period 1906 to 1910, the United States produced nearly 20 per cent of the world's new gold until 1920. From 1921 to 1925 it averaged 13.6 per cent and since then it has continued to decline in relative importance, accounting for only 10.9 per cent in 1927. Final figures for 1930 may place Canada second among the gold producers of the world.

Jan 1, 1931

By A Kamaraj, M Mohanasundaram, R Kumar, P Tikare

This study presents a comprehensive thermodynamic optimisation and sustainability analysis of the secondary copper smelting process for Waste Printed Circuit Board (WPCB) recycling. The study investigates various scenarios with different proportions of WPCB in the input stream, ranging from 0 per cent to 100 per cent. Through thermodynamic modelling using FactSage™ version 8.1, the optimisation process is conducted in three stages. The results of the thermodynamic modelling indicate that the best-case scenario for WPCB recycling is achieved with a 40 per cent proportion of WPCB in the input stream. This case exhibits a maximum copper recovery of 99.93 per cent while minimising the formation of other waste. In addition to the thermodynamic analyses, environmental factors such as the carbon emission index and resource utilisation efficiency are studied. The 40 per cent WPCB recycling case exhibits a resource utilisation efficiency of 93.055 per cent and a carbon emission rate of 0.133. The present investigation highlights the significant benefits of a 40 per cent WPCB recycling scenario through a secondary copper smelting process in terms of base metal recovery and energy efficiency, thus emphasising its potential for sustainable PCB waste management and resource utilisation.

Aug 21, 2024

By Joseph P. Gildner, Michael S. Kucker, Robert A. Robinson

Considerable controversy seems to exist over the extent and nature of information that should be provided in design-build type contracts. Much of this controversy may relate to the types of owners, ranging from private industry to state and federal agencies that are implementing design-build. Philosophies for the development of geotechnical information ranges from no information to a thorough investigation approaching that needed for final design. Several recent projects, such as the Channel Tunnel in Europe, Whittier Tunnel in Alaska, Tren Urbano in Puerto Rico, and Sound Transit in Seattle have taken varying approaches to providing and interpreting geotechnical information for bidders. The pros and cons of these various methods are discussed and assessed.

Jan 1, 2001

The Mine Safety and Health Administration (MSHA) defines an independent contractor as “any person, partnership, corporation, subsidiary of a cor-poration, firm, association or other organization that contracts to perform services or construction at a mine.” Contractors that perform specific types of work are required to report the number of employees who work at coal mines and noncoal mines.

Sep 1, 2007

By Steve Dillingham

Change occurs all of the time. In fact, it’s fair to say that change is a constant. Sometimes the change is inconsequential, but sometimes the change impacts us d i rectly and severely. Take regulations, for instance. Complying with regulatory requirements is just part of the job for those involved with explosives. But in recent years, it seems as if new or revised regulations in areas such as hazardous materials training, drug and alcohol testing, security issues, or local licensing/permitting standards are changing the way we operate on a recurring basis. Simply keeping track of all of these regulations has become a full-time job.

Jan 1, 2003

By S. R. Dismukes

Mining is likely to be targeted by The United States Environmental Protection Agency (“EPA”) as one of its key enforcement targets for fiscal year 2002-2003. Identifying the mining industry as an enforcement target, coupled with an increase in enforcement activity in recent years, places each mining operation at increased risk of receiving enforcement attention. A properly developed and implemented Environmental Management System (“EMS”) tailored for your operation is invaluable in reducing the risk of incurring liability for non-compliance. At the heart of an effective EMS is an audit program that checks the company’s compliance with environmental requirements. In addition, audit privilege (in select states), voluntary self-disclosure, and the attorney-client privilege serve as very effective tools for managing those liabilities that may arise during auditing a well-developed program. Of course, these latter tools are effective only if the auditing program is properly structured and properly managed. EPA and some states also provide varying degrees of immunity for environmental violations that are voluntarily disclosed in writing by the company. However, self-disclosure laws and policies typically prescribe stringent requirements for parties seeking to take advantage of them. For example: U.S. EPA has recently extended the time period in which to provide full written self-disclosure to 21 days. However, U.S. EPA’s revised Self-Disclosure guidance also addresses when a company obtains knowledge of a violation for purposes of triggering the 21-day clock and specifically extends the knowledge requirement to include the company’s agents and consultants. This expansion increases the difficulty companies may have in clearly defining and managing when they obtained knowledge. This difficulty increases the importance of managing factual development and the strategic use of other

Jan 1, 2001

By F. E. Walker

The Bureau of Mines determined total sulfur and sulfur forms for coal in 283 counties in 29 States and 2 fields of the State of Alaska. Specifically, organic, pyritic, and sulfate sulfur were measured of approximately 2,900 samples, and they include most of the coalbeds in the United States.

Jan 1, 1966