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By Lynn L. Rethi, Barbara Fotta

Recent employment figures (taken from the Mine Safety and Health Administration's database) indicate that the number of independent contractor' employees working in the coal mining industry has doubled over the past ten years. As their numbers increase, they become a more visible segment of the industry. [ ] Increased exposure to mining hazards has also brought an increase in the number of fatalities involving independent contractor workers. One gauge that is traditionally used to evaluate the overall safety of an entity is the "number of fatalities." Over the five-year period from 1985-89, 27 independent contractor employees were fatally injured while working on coal mine property. This number increased to 45 fatalities during the subsequent five-year period from 1990-94. Nearly half of these fatalities (47%) were due to accidents involving powered haulage (See Table); 13% were electrical accidents; and 9% were machinery accidents. Combined, these three accident classifications accounted for 69% of all coal nine independent contractor fatalities. Information taken from fatality data is an important piece of the safety puzzle; however, other variables need to he examined in order to better define contributing factors associated with accidents. More specifically, information on trends in fatal and nonfatal accident and injury data is necessary before deciding what approach should be used to improve safety. In order to implement appropriate safety strategies, it is important for safety practitioners to examine all available lost time accident and injury information. The following coal industry data sites specific and present trends of independent contractor employees working in underground locations at coal mines, surface areas of underground coal mines, surface coal mines, and preparation plants. The data compares employment and accidents for time periods at the beginning and the end of a ten-year span from 1985 to 1994. Because the number of incidents involving independent contractors in certain accident categories during any one year may be small, three-year totals are used; the first three years (1985-87) of the ten-year period are compared with the last three years (1992-94). [ ]

By Barbara Fotta, Lynn Rethi

Within the Mine Safety and Health Administration's (MSHA's) classification of metallnonmetal (MAM) mining, the number of independent contractor' employees has increased significantly in recent years. In 1985 independent contractor employee hours reported to MSHA accounted for 4.5% of all M/NM mining employee hours (excluding office workers); by 1994 that proportion had doubled to 9.0%. As a result, these workers now account for an increasingly significant proportion of fatal and nonfatal mining accidents. According to MSHA's statistics, annually computed fatality incidence rates (the number of fatalities per 200,000 employee hours) for independent contractors working in M/NM mining are consistently higher than those for operator employees. Over the five-year period from 1990 through 1994, 53 independent contractor employees were fatally injured while working on M/NM mine property (See Table 1). More than one third of these fatalities (36%) were due to accidents involving powered haulage; 21% were machinery accidents; and 11% percent were falling material accidents. Combined, these three accident classifications accounted for 68% of all independent contractor fatalities occurring on M/NM mine property during these years. Clearly, current efforts to increase the safety of the mining workforce must also address the safety of the independent contractor employee. This report is a preliminary attempt to identify trends in the employment and safety of independent contractor workers by identifying which segments of M/NM mining are experiencing the greatest increases in the number of independent contractor employees and by examining changes in the rates and types of accidents in which these employees are involved. The employment and accident data used in this report were obtained from the MSHA database. [ ]

By E. A. Barrett, L. L. Rethi

Throughout all segments of the United States mining industry, 163 independent contractor employees were fatally injured between 1990 and 1997. Factors that contributed to these injuries were identified after reviewing descriptive information contained in Mine Safety and Health Administration fatality reports for each of the incidents. Thirty-three unique contributing factors were identified and multiple factors were noted for each fatality. Those most frequently discerned were "failure to follow `standard operating procedures"', (35% of the fatalities), "poor positioning of employee" (26% of the fatalities) and "failure to maintain equipment" (23% of the fatalities). Contributing factors were then associated with the accident and job classifications of the victims. Factors having the highest frequencies in the top five accident classifications where most fatalities occurred were as follows: powered haulage - "failure to maintain equipment"; machinery - "poor positioning of employee"; slip/fall of person - "inadequate fall protection" and "failure to wear safety line"; electrical - "equipment contact with power line"; and falling/rolling/sliding rock - "poor positioning of employee. " Among the job classifications in which most fatalities occurred, leading contributing factors were as follows: truck driver - "failure to follow standard operating procedures" and "poor positioning of employee"; laborer/utility man/pumper - "poor positioning of employee"; mechanic/ repairman and welder - "failure to follow standard operating procedures." Recommendations for utilizing contributing factor information as a basis for safety training are proposed. Training programs may be developed that inform independent contractor employees of factors which, in the past, have contributed to fatal injuries in their job classifications. Then, by combining this information with contributing factors identified in "related" accident classifications, a truly focused training intervention that addresses very specific workplace hazards may he developed.

Jan 1, 2002

In May 2000, Kanowna Belle Gold Mines (KBGM) carried out a detailed Truck versus Shaft Haulage Study. The study showed that whilst the shaft option had many operating cost benefits the capital costs were too high, therefore the truck option was selected. In May 2001, the concept of achieving æshaft typeÆ benefits without the capital costs was floated. This is achieved by separating the hoisting of ore from other mining activities. The general concept is that material from underground is transported to a central location and then transported to the surface by a special truck fleet, thus removing the dependency between trucks and loaders, providing the mine with surge capacity and decreasing operating costs. At KBGM these advantages have been gained by installing an ore pass system with a plate feeder at its base that directly loads trucks. This provides the mine with a haulage system with enough surge capacity to remove the interdependency between trucks and loaders. The plate feeder is situated just off the decline which creates the opportunity to use larger more reliable, lower cost trucks. A number of truck types were considered for the truck loop including Elphinstone AD55Æs which are the truck type being used on site prior to the truck loop, CAT 775EÆs and power trailer road trains. This paper covers the philosophy behind the truck loop, the truck selection process, project installation and commissioning, people issues and the benefits expected by the operation. As of May 2002, the project is nearing completion, with decline haulage expected to commence in July 2002.

Jan 1, 2002

By Mark E. Emerson

INTRODUCTION A long time has passed since geologists encountered encouraging mineralization in their regional exploration program for base metals deposits. Detailed drilling during the following two field seasons served to delineate the configuration of the deposit. Various statistical techniques were employed to provide confidence levels regarding the extent of the reserves and to categorize them according to whether proved, indicated or inferred. At this juncture, it appears that the company has an orebody. Time elapsed? - three years; money spent? - $2.5 million. Much remains to be done before the orebody becomes a mine. The company urgently needs to develop new orebodies to replace its existing mines which are being depleted. It therefore has expended sizable amounts in exploration, the life blood of the company. A staff of specialists is maintained to evaluate new projects and to conduct feasibility studies. The scale of new mining projects today is beyond the resources of most mining companies. Bank financing, therefore, is often vital if the company is to survive. The following scenario describes how a company goes about evaluating mine projects and what is needed to meet lender's criteria in securing the needed financing. MINE PLANNING Now that the company engineers have taken over the project, their concern is no longer with finding ore but in developing it. An exploration shaft has been put down and a tunnel driven into the orebody to verify, on a large scale, what has been seen so far only in pencil- like drill cores. A large tonnage bulk sample is mined and shipped off to an independent metallurgical process laboratory for beneficiation testing. The budget is expended to cover engineering studies. Preliminary capical and operating costs are developed in- house and profitability studies are made based or1 assumptions concerning the markets for the main product and the indicated gold, silver, and other by-products. Time elapsed? - four years; cost to date? - $3.5-$4.5 million. The staff prepares its own pre-feasibility study. After review, the Executive Committee authorizes management to proceed with full-scale studies. The task is to make preliminary designs and to develop definitive capital and operating cost estimates. Specialized consultants will be engaged to study slope stability for the open pit and rock strength if underground recovery proves more feasible. If it is near the sea, an oceanographic report might be commissioned to see if the tailings can be disposed of off shore. Environmental impact studies are commissioned from a firm familiar with government requirements and regulations in this important area. The company subscribes for an expensive multi-client study of the supply- demand-price outlook for the product to support its own long-range price forecast. Now all the numbers are available to make a definitive appraisal of the value of the project. Cash flow analyses and sensitivity studies follow. Reams of computer printouts are generated. Time elapsed: five years. Amount spent? - up to $9 million, depending on the size, complexity and attractiveness of the project. Marginal projects always take longer. Finally, an engineering and construction (E&C) company is given the task of integrating and compiling all the data into a feasibility study. The results of dozens of reports, memoranda, computer printouts, and charts are boiled down to one final summary report of a few hundred pages together with conclusions and recommendations. After thoughtful review at a board meeting, the directors authorize management to proceed with detailed engineering work - provided that

Jan 1, 1985

By J. E. Marshall

"The concept of employing a project management team to coordinate all aspects of the construction of a new resource development has gained wide acceptance. This team can be formed from within the staff of large mining companies or contracted from major engineering firms and consultants. The mandate of the project managers usually terminates on successful startup of the operation. For frontier mineral developments in the Canadian Arctic or in the developing countries, startup and the initial year of operation represents the period in which the project is most vulnerable to technical, political and managerial problems. A complete change of the management team or the retention of the construction project managers and the resulting cost combined with the breakdown of organizational accountability within the operating staff .are unnecessary management problems.Independent project management services provide the commitment necessary to sustain the continuity of management through all project phases. Efficiency and the ability to make decisions quickly are characteristics of the many successful small mining companies. These qualities are necessary in the project management group, which will be responsible for up to 90% of the preproduction costs.Continuous project management in the construction and operational phases of a mineral development are common in the iron ore industry, but remain anomalous in the base metal, energy mineral and industrial mineral fields.The Nanisivik project on Baffin Island in the Canadian Arctic is used to illustrate the advantages of total project management through construction and operation.Total project management has further potential for foreign interests and financial and utility organizations desirous of participating in the Canadian mining industry, but with no direct involvement in the construction or operating management. Participation agreements in the operating phase of a project can be negotiated to have management fees related to both the production and the profits of the enterprise."

Jan 1, 1980

The paper outlines the history and current status of the VALMIN Code and sets out the background, methodology, results and recommendations of the Independent Review of the VALMIN Code undertaken during 2001 under the Chairmanship of Ian Goddard. The paper is based on the final report of the Taskforce, which was submitted to the Board of The AusIMM for consideration.

Jan 1, 2002

Jan 1, 1964

Jan 1, 1963

The following discussion occurred on the afternoon of Sept,. 22, 1930, as part of the fall meeting of the Iron and Steel Division at Chicago. About seventy-five men attended this session. C. B. Murray opened the meeting, as follows: C. B. Murray, Cleveland, Ohio.—It is very encouraging to see so many here this afternoon to discuss this important matter of beneficiation. The producers of ore, I am sure, are anxious to furnish the grade of ore that the consumer wants. The consumer sometimes wants that which cannot be economically produced and often the producer cannot understand why the consumer wants certain things. It was to bring together these two interested parties that this meeting was proposed. I was appointed the chairman of the meeting, chiefly because I happened to be the chairman of the Iron Ore Committee of the Institute. I know a little about iron ore but have not perhaps kept up with the times in blast-furnace practice. I am asking Mr. Sweetser, who is well informed from both sides, to take over the meeting and carry on the discussion. R. H. Sweetser, Columbus, Ohio.—We want to have a free discussion between the iron-ore men and the blast-furnace men as to just what we are trying to reach in the beneficiation of iron ores. Many of those present have had a great deal of experience. There are men here from the ranges who have been passing through the experimental stage of beneficiation of iron ores, and there are some who have already gone on to commercial production. We have reached the point where the beneficiation of iron ore is important to the whole iron and steel industry. The connection between iron-ore beneficiation and the cleaning of coal is so close that I think we can profit by working very close to the coal people. Some Aspects of the Iron-ore Situation W. G. Swart, Babbitt, Minn.—I was very much interested in Mr. Richards'* paper on tonnages and the 20-year life. There is one interesting thing about the ore reserves; that is, the irregular distribution of that tonnage. On the Mesabi Range, for example, the United States Steel Corpn. owns between 70 and 75 per cent. of the reserve tonnage. They ship bctween 40 and 50 per cent. of the annual Lake Superior

Jan 1, 1930

In the past few years the hydraulic aspects of rotary drilling have received considerable attention. It is generally recognized that accurate prediction of circulating pressures is desirable, particularly in those areas where a delicate pressure balance is necessary to prevent both blowouts and lost circulation. For calculation purposes the standard hydraulic equations for the pipeline flow of Newtonian fluids have been altered to facilitate similar calculations for non-Newtonian or plastic fluids.'.' This latter classification includes most colloidal types of drilling muds. Two properties: plastic viscosity, un, and Bingharn yield value, Y,, are commonly used to define the flow characteristics of a plastic fluid. These are commonly obtained with multispeed viscosimeters such as the Fann V-G meter.3 Normally these measurements are obtained at some surface temperature, and are not corrected to circulating temperatures for calculation purposes. This may result in considerable error, particularly in the laminar flow calculations which comnlonly apply to the drill pipe-borehole annulus. The purpose of this study was to investigate the effect of temperature on the flow properties of some water-base muds. A laboratory model Fann V-G meter was used for measurement of viscosities, yield values and gel strengths. An aluminum water jacket with O-ring seals was machined to fit around the mud cup of the Fann meter. All mud samples were prepared by thorough mixing in a Hobart mixer. Viscosity and gel strength measurements were made with the Fann meter using standard procedures. Flow properties of muds were studied at 80, 120, 160 and 180°F. The compositions of the test samples are given in Table 1. The typical effect of temperature on the flow properties of these drilling muds is illustrated by Fig. 1. It was found that plastic viscosity and apparent viscosity decreased with an increase of temperature. However, the curves were not linear, and did not appear to follow any definite trends or patterns. Yield point data showed much more scattering.' Since a usable method for predicting drilling mud flow behavior with temperature was desired, an attempt was made to find a simple relationship between these variables. The basic approach used by Havenaars for predicting the same effect on turbulent viscosity resulted in Fig. 2, which shows that

Strain-Hardening Exponent of Cross-Rolled Beryllium Sheet by S. R. Maloff, Vol. 215, No. 5, page 872, was omitted from Table of Contents for the October issue. Stabilization Phenomena in Beta Phase Au-Cd Alloys by Howard Birnbaum, Vol. 215, No. 5, page 786. The figure denoted Fig. 1 should be Fig. 3, Fig. 3 should be Fig. 4 and Fig. 4 should be Fig. 1. The captions are in the proper sequence. Activity of Carbon in Liquid Iron Alloys by Tasuku Fuwa and John Chipman, Vol. 215, No. 4, page 708. First equation, right hand column, page 710 should read

Jan 1, 1960

By J. W. Walker, G. J. Heuer, E. W. Hough

An improved apparatus is described for the deterrni-nation of interfacial tension* by the pendant drop method in the pressure range from 15 to 15000 psi and the temperature range from 100º td 280°F. The chief characteristics of this apparatus are reliability and ease of operation. Temperature control was accomplished by means of an electrically heated jacket which could he completely removed while cleaning the apptrratus. The cell was designed so that the camera could he placed about I in, from the window without overheating the carnera lens. Separate "0" rings employed to seal each window and corresponding window backup plate gave very reliable window operation at 10,000 psi. An extra pistorr-cylinder combination was added so that a high compression ratio could he attained when gas was employed as one phase in the pendant drop cell. Other essential parts of the system were similar to an apparatus already described.' The interfacial tension for carbon dioxide and water varies from about 69 dynes/cm at 15 psi to about 19 dynes/cm at 1,250 psi for 100°F. For pressure.r between t,500 and 3,500 psi, the interfacial tension is between 32 and 24 dynes/cm at this temperature. The interfacial tension at 280°F varies from about 50 dynes/cm at 200 psi to about 17 dynes /cm at 10,000 psi. The maximum surface excess for carbon dioxide, assuming the surface excess of water to be zero, occurs at about 1,500 psi jor the 100°F isotherni and Itas a value of about -79 X 1014 mol/sq cm. At 160°F this maximum IS shifted to about 2,000 psi and has a value of about 10 X 1014 111ol/.sq cm. Other maxima, us well as several minima, are present at these and other temperatures. Judging from the data on the solubility of water in carbon dioxide at elevtrted pressures2,3, it appears that the principal maxinza natned are in regions of increasing solubility of the water in the carbon dioxide rich phase. INTRODUCTION AND APPARATUS A pendant drop interfacial tension apparatus which would accommodate an opaque liquid in a gas phase was constructed several ycars ago' for industrial purposes. This apparatus was used as a starting point for the present development. The objective of the present development was to enhance reliability and convenience of operation. Other articles'" have described pendant drop apparatus which could not accommodate a gaseous phase adjacent to the windows. A schematic diagram of the apparatus is shown in Fig. 1. The water used followed the path; A, intro-

[Page Officers of the Institute 5 Minutes of Twenty-first Meeting 9 The U. S. Fuel Company's Tipple at the Hiawatha Mine John M. Jennings 11 Some Experiences With Mechanical Loading in Central Pennsylvania¬ O. G. Sharrer 13 Mechanical Loading Underground- A. W. Dickinson 25 Operation by Long-Face Conveyor Method at Sweetwater Mine Glen A. Knox 39 Discussion of Mechanical Loading 44 Discussion-Safety in Mechanical Loading 45 New Steel Tipple, Spring Canyon, Utah- G. A. Murphy 46 A Theory on the Cause of Spontaneous Combustion-C. P. Crawford... 48 Rock Dusting in the West-D. Harrington 50 Mudite-L. C. Clare 57 Discussion of Harrington's and Clare's Papers 59 Material for Rock Dust-Prepared Discussion-Edward K. Judd 60 Tipple and Mine of the Columbia Steel Corporation-T. C. Harvey 63 Mechanical Stoking of Domestic Fuel-Joseph Harrington 67 The Garrison Automatic Domestic Stoker-Lloyd Garrison 70 Discussion of Domestic Stokers 71]

Jan 1, 1925

[Page Minutes 5 The Power Problem of the Coal Mine 8 A. L. Jones. Discussion of A. L. Jones' Paper 13 Why Alternating Current 15 C. E. Drennan. Discussion of C. E. Drennan's Paper 17 Dry Cleaning Coal at Brilliant Mine 26 F. A. Young. The Possible Substitution of Pulverized Coal for Fuel Oil in Smelting Operations in the Southwest 33 T. H. O'Brien. Special Discussion of Paper of T. H. O'Brien by D. C. McClure 35 Discussion of T. H. O'Brien's Paper 40 The Gebo Mine 45 J. C. Rae. Low Temperature Carbonization 52 J. F. McDermott. Safety Discussion 54 Order of Business 57]

Jan 1, 1923

[Page Minutes 7 Discussion of L. S. Ickis' Paper 20 City Planning and Landscape Architecture for Western Coal Camps, by S. R. DeBoer 22 Discussion of Thos. Foster's Paper 26 Discussion of Safety Committee Report 30 Discussion of R. L. Hair's Paper 52 Discussion of H. I. Smith's Paper 61 Miscellaneous Discussion 62 Discussion of Thos. A. Stroup's Paper 70]

Jan 1, 1924

Jan 1, 1965

Jan 1, 1934

[Page Minutes 5 Present Status of Petroleum Industry 9 F. M. Van Tuyl. Developments Along the Line of Low Heat, Carbonization 13 A. C. Watts. Uses for Fine and Pulverized Coal 14 C. A. Allen. Have Mining Engineers Accepted All That Developments in Machinery Apply? 16 R. Dawson Hall. Coal Mine , Accidents and State Mining Law 23 D. Harrington. Harmony and Co-Operation 26 H. F. Nash. Personal Dangers 28 John Bevan. Methods of Improving Safety and Health Conditions 29 C. A. Allen and A. L. Murray. The Economic Relation of Accidents and Preventable Diseases to the Coal Mining Industry 39 Recent Developments in the Use of Electricity in Mines 43 Graham Bright. Discussion of Graham Bright's Paper 48 Mine Safety Work at Dawson, N. M 49 W. F. Murray. Mine Safety Work 54 Eli Follett. Wire Rope in Mining Operations 56 James F. Howe. Discussion of F. E. Shepard's Address 69]

Jan 1, 1922

Jan 1, 1929