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By H. S. COOLEY

TO talk about a "factor of economy" in connection with the wire ropes used in mining practice may be coining a new phrase. If such be the case it needs no other apology than that economy in wire rope usage is so bound up with the factor of safety as to justify a similarity in naming that makes one suggest the other. At the latest Wire Rope Research Conference, held under the auspices of the A. S. M. E., Re- search Committee and Engineering Foundation, data were introduced covering mine ropes working under

Jan 1, 1930

To develop a conceptual design for an automated longwall mining system, one should know what has been done, what is being done today and what is being planned for tomorrow. The bibliography referenced and discussed in this report provides a good source for that knowledge. To scientifically determine where attention should be focused to up-grade a system, the system must be quantized as far as possible. The Mechanization Profile of Appendix A-I is discussed in this report and has been used to analyze and determine the degree of mechanization currently in use and/or described in the literature for all three major elements of the long-wall system, namely, Winning, Roof Support and Haulage. The charted profiles make it self-evident where attention and design effort is needed to remove human operators from the face of the mine.

Jan 1, 1975

By Deren Zhu

Based on the results of in-situ observations and physical model analysis, a computer simulation method, FEAEBP, has been developed to predict the behaviors of main roof breakage in longwall mining by considering it as a Kirchhoff plate on Winkler elastic foundation. This method in used to investigate the initiation, and development of the breaking process of main roof and its displacement field before and after its breakage. In this paper the simulation method is introduced, characteristics of the displacement field of the main roof is discussed and monitoring variation of the displacement field of the main roof in a Chinese longwall face is demonstrated.

Jan 1, 1989

By Y. Luo

A PC based computer model has been developed by the authors for predicting the surface subsidence due to underground coal mining. Its reliability, comprehensiveness and user friendliness demonstrate that it is a good tool for the mine operators, government agencies and scientific researchers alike.

Jan 1, 1989

By Thom Sedun

No sector of the mining industry is more closely tied to local communities than aggregates. Noise, dust, traffic, visuals aesthetics and environmental impacts all fall under the purview of neighbours, local governments and nongovernment organizations. It is no surprise that aggregate operations may not be welcome neighbors in many communities. In British Columbia (BC), the regulatory environment for aggregate operations includes a local component of municipal bylaws and land use-planning in addition to the usual suite of federal and provincial statutes that apply to its sister mining sectors. Additionally, under common law aggregate extraction is not considered to be a land use subject to land use zoning, and some aggregate processing activities can be regulated by zoning. Often traversing multiple local government jurisdictions, aggregate producers find themselves negotiating not only local traffic, but also a mosaic of regulatory environments. There is an opportunity in this present situation to facilitate the application of current technology and practices in the mitigation of many community and environmental concerns associated with aggregate operations. Moving a bulk commodity is a volume-based business, and operators often don?t have time for matters that don?t directly or obviously affect the bottom line. Regulatory agencies often play multiple and complex roles with respect to their industry, not the least of which is the fiduciary role. Balancing how and when to assist an industry is often a difficult decision. For the aggregate industry in BC, the Ministry of Energy and Mines saw an opportunity to assist not only aggregate operators, but also regulatory agencies, local governments, and the general public. Through investing in the Aggregate Operators Best Management Practices Handbook (handbook) project, the Ministry of Energy and Mines (MEM) believes that it will realize a return of upheld community values, enhanced environmental protection, improved regulatory compliance, reduce disputes and a stronger provincial aggregate industry. It is the intent to publish the handbook electronically through the MEM website later this year.

May 1, 2002

By Robert T. Davis

An award is a form of recognition given for superior performance in a special field of endeavor. Each year awards are given by the Joseph A. Holmes Safety Association and the National Safety Council to the coal-mining industry's underground and open-pit mines that have worked a specific number of man-hours without a lost-time injury. These awards have a dual significance in that they prove efficiency can be attained without injury to persons. Safety awards do not result from luck or good fortune but do result from sincere desire coupled with sufficient effort and cooperation to achieve a desired goal.

Jan 1, 1964

By W. D. Sinclair

"Between 1934 and 1956, nearly 31 million grams of gold were produced in the Matachewan area from deposits on properties belonging to Young-Davidson Mines Limited and Matachewan Consolidated Mines Limited. In 1979, production from these properties was renewed by Pamour Porcupine Mines Limited.Most of the gold produced has come from relatively lowgrade deposits (3.4 gl t or less) that occur in an east-trending belt of dykes and irregular bodies of trachytic syenite. Although small by comparison, these deposits have some of the characteristics of porphyry copper-molybdenum deposits. The mineralized syenite contains up to 5 per cent disseminated pyrite and is highly fractured and cut by quartz and quartzcarbonate veinlets. Gold occurs as native gold along fractures, in quartz veinlets and as minute inclusions in pyrite. Minor chalcopyrite and trace amounts of scheelite, molybdenite and galena are also present. Mineralization was accompanied by potassic alteration, consisting mainly of potassium feldspar.Some gold was also produced from small, but higher-grade, deposits in volcanic rocks. These deposits occur near the syenite-hosted deposits and consist of quartz veins and stringers mineralized .with pyrite and gold. Minor gold is present in some low-grade, porphyry-type copper-molybdenum occurrences and, locally, in large, isolated quartz veins.Lead isotope analyses suggest that the gold deposits were formed at about 2700 Ma and were locally remobilized at approximately 2400 Ma, following the Kenoran orogeny. The deposits appear to be genetically related to felsic magmas emplaced in an epizonal environment and deposited from hydrothermal solutions relatively concentrated in S and K20."

Jan 1, 1982

By W. F. Dietrich

1. On St. Thomas and St. Croix, and possibly also on St. John, low-quality red-burning clays probably can be developed to provide the major part of the raw materials for structural clay products and earthenware pottery. 2. The potential sales volume for structural clay products is too small to sustain a plant in the Virgin Islands to manufacture such products in competition with Puerto Rico; however, handmade patio tile might be produced successfully. 3. The market for pottery utility wares in the Virgin Islands is too small to justify a plant devoted solely to the production of such wares; but it may be feasible to evolve a diversified community activity to make jugs, pots, casseroles, bowls, charcoal burners, patio tile, and other items.

Jan 1, 1955

By A. C. Fieldner

This is the tenth annual report of research and technologic work conducted by the Bureau of Mines on the occurrence, properties, mining, preparation, and uses of coal and coal products. These annual reviews are guide's to the current work-and publications of the Bureau but do not replace the more complete reports published under the authorship of the individual investigators on specific problems in Bureau of Mines bulletins, technical papers, reports of investigations, and information circulars and in the technical press. The Annual Report of the Director of the Bureau of Mines to the Secretary of the Interior for the Fiscal Year ended June 30, 1945, summarizes the year's work on coal as follows: Coal and Coal Products The United States maintained its No. 1 industrial position in supplying fuel for war and in preparing for peace through more complete mining, improved preparation and up-grading of coal for special uses, and better utilization of coal in industrial establishments and homes.

Jan 1, 1946

By Carl R. Peterson

[In lTI n,v und I'gr'oun nllnin~ Opt'I'ali n' the high . t cost is the loading and I 3ulage of t tln-of -D"'line ot'. 01' hauling costs can be r duced signifi-cant\v with the us ~ (r \) >It corn'e)'OI' " a COnlTllOn pl'acti c i.n coal and other s 0 t'L rn I n r' a l III i, n e , '. Jf 0 vel s i z ' () f' e can bee 1 i 11.11 tl ate I rH'i 0 I' lO C n v e . in g, ]

Jan 1, 1976

By Philip Morey

Large scale surface coal mining will be required to fill future energy demand in the United States. In realization of this long-term commitment to coal resources, the U.S. Energy Re-search and Development Administration sponsored a study to determine the costs and problems of large-scale surface coal mining. As a result of this study a series of computer models were developed that can be used by government and industry to: 1) facilitate mine design and equipment selection, 2) provide detailed analyses of mining and processing costs. Two types of models were developed: detailed simulation models, which provide detailed information on mining systems and equipment to assist in mine design and equipment selection1 and broad models, which provide a first-order evaluation of deposits and new ventures for an entire mining complex. The complete model series permits examination of surface coal mining under a variety of terrain conditions. Six different mining methods were analyzed and documented during the overall project: 1) Area stripping with draglines, 2) Area stripping with draglines, extended bench, 3) Contour stripping with draglines, 4) Area stripping with shovels (loaders) and trucks, 5) Mountain top removal with shovels (loaders) and trucks, 6) Multiple dipping seam mining with shovels (loaders) and trucks. Each major operation in the coal mining pro-cess is represented in these models so that the best methods and equipment may be selected and 50 that the impact of such selection will be reflected in estimates of capital investment, operating costs, and coal price. Individual models allow the user to separately analyze overburden removal, overburden drilling and blasting, coal drilling and blasting, coal loading and hauling, coal preparation and handling, land reclamation, and premining, facilities, and administrative expenses. Because it is impossible to cover all the models in this paper, only the detailed simulation models representative of the technique "area stripping with draglines," are described. The Fort Union Strippable Coal Resource Region, one of eight test cases, is used as an example to describe the models.

Jan 1, 1978

By J. A. Kost

The contract objective was to evaluate the effectiveness of available dust-control technology for double-drum shearers. Eight underground surveys were conducted to evaluate drum design, drum spray nozzle locations, ranging-arm sprays, water quantity, wetting agents, and cutting techniques. The final report is made up of eight dust-control technique reports, each discussing, details of the individual mine surveys.

Jan 1, 1985

The analysis of in-mine grounding systems began with an extensive literature search which is still in progress. About a dozen articles have been found which deal directly with grounding problems on low voltage power systems or mine power systems. These systems have special grounding problems because normal load currents can be nearly as large as many types of fault currents. Information has been collected on the influence of cable spacing) conduit geometry, location of nearby conducting structures, etc., on the magnitude and path of fault current. Many other articles have been found which are less directly related to mine ground system analysis. The in-mine ground system analysis team has also inspected portions of two mine power systems to become familiar with the practices used in grounding. One electrical engineer and several other mine personnel have been interviewed concerning mine power system grounding practice. Already several aspects of the mine grounding system have been marked as requiring special attention.

Jan 1, 1975

By P. James

"INTRODUCTION Control of target stream pH is very important in leach mining and treatment of MIW (mining influenced water). On the production side, solution acidity can impact SX (solvent extraction) effectiveness through PLS (pregnant leach solution) and raffinate pH. Many older operations and legacy mining sites generate ARD (acid rock drainage) that is too weak for profitable metal production by conventional means and faces costly wastewater treatment for mitigation and disposal. For wastewater and environmental treatment, neutralization to precipitate and remove metal contaminants to clean the wastewater is the dominant approach. Traditional lime neutralization and precipitation is most often used but results in large amounts of mixed metal sludge requiring costly disposal. Blue Planet Strategies (BPS); which focuses on improved resource utilization targeting electrolytic treatment and waste conversion into resources, has developed a new “reagentless” neutralization process. Electricity is utilized in its proprietary DEMET™ (Dynamic Electrolytic Metal Effluent Treatment) platform capability to controllably raise target stream pH. The method offers a simple, low-cost approach yielding cleaner treatment chemistry. It can result in less sludge generation and enables possibilities to selectively recover contaminants as potentially saleable products for new revenue generation to offset further offset treatment costs. DEMET Overview BPS’s patented electrolytic DEMET platform leverages solid scientific and chemistry foundations through its advanced design to achieve capabilities and performance not previously realized. DEMET technology combines separated compartment electrolytic cell functionality with proprietary advanced dynamic electrodes and cell configurations to achieve a variety of chemistries and processing targets.[1-6] DEMET‘s unique elements can yield higher processing rates at practical efficiencies, lower energy consumption, plus improved processing stability and lower maintenance requirements due to enhanced resistance to cell fouling and shorting; while also thwarting cross stream (catholyte vs. anolyte) contamination. Consequently, DEMET can provide a superior, extremely versatile, and more cost-effective electrolytic treatment option where a multitude of FEED and PRODUCT stream combinations might be employed in comparison to traditional tankhouse electrolytic cells."

Jan 1, 2015

Studies of coal reserves have shown that the total augerable reserve base for the United States is estimated to be five billion tons under the current state of mining technology; the potential reserve base at 850-ft penetration is estimated at 20 billion tons. It is with the idea of improving coal recovery, a basic objective of Project Independence, that new concepts, such as modifications and improvements in current machines and development of ways to recover pillars left by current augering, are required. Unless recovery is improved, these potential reserves amount to lost coal.

Jan 1, 1975

By Christopher Mark

Multiple seam interactions are a major ground control hazard in many U.S. underground coal mines. The two most common types are: ? Undermining, where stress concentrations caused by previous full extraction in an overlying seam is the primary concern, and; ? Overmining, where previous full extraction in an underlying seam can result in stress concentrations and rock damage from subsidence. The National Institute for Occupational Safety and Health (NIOSH) has completed a major study aimed at helping to identify the location and likely severity of these interactions. In the course of field visits to mines throughout the U.S., more than 300 multiple seam case histories were assembled into the largest data base of multiple seam case histories ever collected. These data were analyzed with the multivariate statistical technique of logistic regression. The study also employed LaM2D to estimate the multiple seam stresses, ALPS and ARMPS to determine pillar stability factors, and the CMRR to measure roof quality. The study resulted in the development of a computer program, called Analysis of Multiple Seam Stability (AMSS), which can help mine planners to evaluate each potential interaction and take steps to reduce the risk of ground control failure. AMSS first evaluates pillar design by calculating the single seam Stability Factor (SFSS) using ALPS or ARMPS. It also automatically generates a LaM2D analysis that provides the additional multiple seam stress so that the final, multiple seam SFMS can be determined. The second part of the AMSS procedure builds upon the statistical findings that overmining is much more difficult than undermining, isolated remnant pillars cause more problems than gob-solid boundaries, and weaker roof significantly increases the risk of multiple seam interactions. AMSS quantifies these effects and predicts the outcome in terms of three levels of risk: GREEN (where a major multiple seam interaction is considered unlikely), YELLOW (where adding a pattern of cable bolts or other equivalent supplemental support could greatly reduce the probability of a major interaction.), or RED (a major interaction should be considered likely, and it may be desirable to avoid the area entirely).

Jan 1, 2007

By J. S. UNGER

A LARGE proportion of the coke used is made in the by-product oven from the high-volatile coals mined in the adjacent district. At the beginning it was feared good by-product blast-furnace coke could not be made with our coals. By experimenting with various mixtures of coals, coking time, oven design, and coking temperatures, much has already been accomplished. The results show that a hard, dense coke, not easily broken by handling, can be produced. In its present state it is not all that could be desired, but it is being constantly improved. Such coke has been used alone as the fuel on several of the blast furnaces producing the highest daily production in the Pittsburgh district. Many of the coals in the Pittsburgh district when coked in the by-product oven yield a gas which contains a high percentage of sulfur, which is objection- able for many metallurgical operations. As this fuel is gradually replacing the ideal fuel, natural gas, which is becoming less plentiful, studies are being made of the best methods for purification. Some metallurgists believe sulfur to be a very injurious element in steel. Recent investigations by Government bureaus, scientific bodies and private firms, seem to indicate that a reasonable amount of sulfur may exist in steel without detriment. Without wishing to provoke any metallurgical controversy on the subject of sulfur, the fact remains that the daily purification

Jan 1, 1926

By Pilon CG, Deakin RC

It is proposed that a waste rock dump be constructed on slopes consisting of soft colluvium and weathered Chim Formation mudstone at the Porgera Gold Mine, in Enga Province, Papua New Guinea (PNG). Geolog- ical, geomorphological and geophysical investigations were conducted in support of geotechnical studies to assess the physical character of the 6km2 site. Geomorphological studies focused on the extent and nature of colluvium cover and landslide activity. Detailed ground traverse mapping resulted in classification and delineation of eight terrains and seven material types. Seismic refraction and resistivity profiling, combined with drilling, provided subsurface data. Results were presented as standard profiles, coloured contoured sections and plans. Subsurface features, including deep colluvial channels, buried cliffs, slump blocks and buried alluvial channels, were identified. Results of the combined investigations allowed designers to model the colluvium/ bedrock surface and identify critical areas of deep, mobile colluvium and weak bedrock. A design approach was developed which accounted for the morphology of landslide systems and distribution of colluvium types.

Jan 1, 1991

By Robert W. Waytulonis

Mining regulations pertaining to the use of diesel engines were solicited from foreign countries with mining operations by the Bureau of Mines. Responses were received from 27 countries; the information received and U.S. regulations were reviewed, and those parts pertaining to the use of diesel engines in underground mining were synopsized according to the following subject categories: types of engines permitted, testing and certification procedures, fuel quality specifications, emission control requirements, procedures and frequency of testing exhaust gases, mine air quality and quantity (ventilation) requirements, procedures for testing mine air quality and quantity, and noise standards. All categories except the types of engines permitted and testing and certification procedures are summarized in tables. Contacts are provided for each country to facilitate inquiries concerning regulation revisions or interpretation.

Jan 1, 1987

By J. L. Jambor, J. E. Dutrizac, J. B. O'Reilly

The present-day metallurgical community is quite familiar with the use of jarosites [MFe3(S04)2(0H)6 where M = K, Na, NH4, Ag, 1/2Pb, etc.] as a means of controlling iron, alkalis and sulphate in hydrometallurgical circuits. This modern precipitation technology has found an increasingly widespread application in the zinc industry111 and is gradually also being extended into the hydrometallurgical processing of copper and cobalt121 . The chief advantage of jarosite precipitation is that the iron precipitate settles and filters well, and gives low losses of divalent metals in the washed residue. Although this jarosite precipitation technology was developed only within the past twenty years, man's involvement with jarosites extends back to antiquity, and jarosites have played an important role as a source of silver in several ancient metallurgical centres. In the early days of this century, argentojarosite was an important local source of silver at the Tintic Standard mine, Dividend, Utah, where over 200 000 oz of silver were recovered from highgrade natural jarosite over a three-month period 131 . At the Matagente mine in Peru, pockets of argentiferous plumbojarosite up to 40 m thick were mined and processed by the Indians prior to the arrival of the Spaniards14-51 . In Cyprus there are vast jarosite deposits associated with the ancient mining sitesl51 , but exploitation of these jarosites has been insignificant because of their low silver values. The most extensive mining of silver-bearing jarosite, and certainly the oldest documented instance of such jarosite exploitation, was in the vast pre-Roman workings at Rio Tinto, Spain. This mine, the greatest single miningmetallurgical site currently known from the ancient world and also the oldest site of more or less continuous metal production, has witnessed many metallurgical firsts. Aside from the initial processing of jarositic ores for their silver values, the development of large-scale hydrometallurgy also seems to have occurred at Rio Tinto. As early as 1737, copper was recovered by cementation on scrap iron from the mine waters at Rio Tintol51 . Large-scale heap leaching of calcined ore commenced with the British operations in 1876 and, by 1900, raw pyrite was heap leached to recover associated copper values161 .

Jan 1, 1999