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Mine waste and mine reclamation are topics of major interest to the mining industry, the government and the general public. This publication and its companion volume are the proceedings of a conference held in Pittsburgh, April 19-21, 1988. There were nine sessions (50 papers) that dealt with the geochemistry, hydrology and problems of mine waste and mine water, especially acid mine drainage. These comprise Volume 1. The nine sessions (43 papers) that dealt with reclamation and restoration of disturbed lands, as well as related policy issues, are included in volume 2. Volume 2 also contains the ten papers that pertained to control of subsidence and mine fires at abandoned mines. Poster session presentations are, in general, represented by abstracts; these have been placed in the back of both volumes.

Jan 1, 1988

Industrial minerals enjoyed a fairly successful year in 1978, despite the sluggish economy, inflation, and environmental restrictions. A glance at US Bureau of Mines statistics shows that, in general, production of industrial minerals increased from + 1% (salt) to as much as 26% (sulfur, other than Frasch or recovered). A few industrial minerals showed a decline; fluorspar production, for example, registered a 23% decrease in 1978 from 1977 due to the closing of three domestic mines. Bromine, natural sodium sulfate, Frasch sulfur, and vermiculite also had production decreases of 2-6% in 1978.

Jan 5, 1979

By R. Filippone, Donald Leroux, Colin Hardie, G. Leichtle, Cesar Gomez, Jim A. Finch

"Bubble surface area flux (Sb) is the surface area of bubbles per unit time per unit cross-sectional area of flotation machine. The units are: (m2 bubble surface/s)/(m2 cell) or s -1. For bubbles of mean size db (m), s b = 6-Qg/A db where Qg is the gas rate (m3/s), and A the cell cross-section (m'). This parameter is now receiving wide attention as the possible key machine variable in flotation diagnosis and modelling. The concept is described and the potential use of sb is illustrated by work on flotation columns and mechanical cells. In column flotation of recycled paper, the dependence of ink recovery on s b was the same regardless of size of column or type of sparger. In mechanical cells, it has been established that the rate constant is related to Sb independent of impeller type.The use of s b is limited by the problem of measurement, primarily that of estimating db. A prototype probe designed to estimate db (and hence sb) based on conductivity measurements is described. Exploratory work with the probe in a mechanical cell suggests the promise of making estimation of s b routine.INTRODUCTIONFlotation is the result of interaction among variables associated with the feed particles, chemistry and the machine (flotation cell). Trying to isolate the effects of each aids in process diagnosis and is at the centre of attempts to model flotation. The machine variables that have been investigated include the air flow number, the power number and specific power (Harris, 1976). None have survived as the basis for predicting flotation response perhaps because they did not include directly the properties of the bubble swarm (or dispersion). Recently, Gorain (1 997) explored the relationship between the flotation rate constant and various ""gas dispersion"" parameters notably: superficial air rate (Jg = Qg/A, where Qg is the volumetric gas rate and A is cross-sectional area of cell), bubble size (db), gas holdup (Eg, i.e., the volumetric fraction of a cell occupied by gas) and bubble surface area flux (sb = 6.Jg/db). Of them all, Gorain et al. (1997) conclude that the latter, the surface area flux, correlated best with the flotation rate constant. This concept was adopted from column flotation where it was used to estimate, among other factors, the maximum amount of gas that could be injected (Finch and Dobby), 1990). Let's start by reviewing the concept. Following that some examples of where the concept has been applied will be described to illustrate the current interest and finally we will consider how to measure the surface area flux."

Jan 1, 1999

By Pengfu Tan

Electric arc furnace (EAF) dust from the steel industries is listed by the United Sates EPA as a hazardous waste under the regulations of the Resource Conservation and Recovery Act due to the presence of lead, cadmium and chromium. The disposal of the approximately 650,000 tons of EAF dust per year in the U.S. and Canada is an expensive and unresolved problem for the majority of steel companies. The Waelz process has been considered as the best process for treating EAF dust. A process model, combined thermodynamic modeling with heat transfer calculations, has been developed to simulate the chemical reactions, mass and heat transfer and heat balance in the kiln. The injection of air into the slag and the temperature profile along the kiln has been modeled. The effect of (CaO+MgO)/SiO2 on the solidus temperature of slag has been modeled also and discussed. Some optimizing results have been presented in this paper.

Jan 1, 2005

By A. B. Hooker, E. J. Coggeshall

"Dry cells are modified wet primary cells in which the electrolyte is held by absorbent material so that it does not spill aid the cell jars are sealed to prevent evaporation of the absorbed electrolyte. Most dry cells in commercial use are modifications of the Leclanche wet cell. In their usual form they have a hollow cylindrical zinc negative pole that constitutes the containing vessel. An absorbent material, either as a lining in the zinc jar or a bag, separates the zinc cylinder and a rod or flat plate of carbon placed axially inside. A mixture of crushed coke, graphite, and manganese dioxide is tamped about the carbon rod, and the whole mass is saturated with salaanoniac-zinc chloride solution.Dry cells are suitable for services that require minute currents continuously or larger, though limited, amounts of current intermittently. Though limited in this way, they have a wide use, even in underground mining. This paper details some of the applications of dry cells in mines, particularly from the standpoint of greater safety through their use.APPLICATIONSThere are four fields of application of dry cells to mining: (1) Electric shot firing; (2) auxiliary lighting; (3) signaling; and (4) testing.SHOT FIRINGFiring an electric detonator requires very little electrical energy because although the current flow may be 1 to 3 amperes the duration of flow is so small (1 to 4 milliseconds) that the energy withdrawal per shot is almost negligible. Batteries for shot firing need not be large; they may be used for firing either single or multiple shots."

May 1, 1934

By Mary Ellen Bruce Large, Antonio Marinucci, Silas C. Nichols

Tip post-grouting of bored pile (drilled shaft) foundations refers to a method where cementitious grout is injected beneath the tip of a shaft to improve the overall performance of the constructed foundation. This technique, when performed satisfactorily and in the appropriate ground conditions, enhances axial load-displacement performance by improving the mobilization of pile’s resistance. Potential benefits associated with tip post-grouting include reduced settlement under loading, better alignment of load transfer curves, and improved ground beneath the base of the bored pile. However, to be able to realize the benefits attributed to this method, the design, construction, of both the bored pile and the post-grouting system must meet a minimum level for quality assurance. The various factors affecting the successful installation and performance of a bored pile (e.g., workmanship, base cleanliness, borehole integrity, and concrete placement) have been discussed by numerous practitioners and researchers in the available technical literature. For a conventional (i.e., ungrouted) bored pile, acceptance is based on a combination of visual inspection, material testing, and the results of integrity and/or performance testing of the constructed pile. A properly executed tip post-grouting program can be a relatively comprehensive and complex process, which is typically evaluated throughout the construction process based on the results of prior projects and/or on test pile(s) at the particular site. For tip post- grouting programs, verification procedures and acceptance criteria should be established during and incorporated into the design process to ensure design intent and objectives are achieved. Project specifications should be produced to ensure performance requirements are achieved. This paper will present and discuss factors affecting the successful execution of tip post-grouting, including grouting criteria, instrumentation, reliability and uncertainty with the method and outcome, and verification and acceptance. INTRODUCTION Constructing bored piles (drilled shafts) is increasingly more challenging given the lack of ideal site locations, tight project site confines, difficult or restricted access, greater demands on drilling equipment, and close proximity to adjacent structures. To evaluate the feasibility of bored piles as an appropriate foundation system, a myriad of factors is evaluated during design, including site conditions and constraints, budgeting and scheduling, reliability and risk exposure, presence of and depth to adequate load bearing soils/rock, and the magnitude of the imposed loading. Moreover, updated design codes increased load demand per element, and improved material strengths have led to more complex foundation designs, larger foundation elements, and significant increases in load magnitude. Monopile (monoshaft) foundations have been utilized where one large bored pile is used in lieu of a group of piles connected via a pile cap. In addition, to accommodate the design criteria, site conditions, and imposed loading, the geometry of the bored piles being designed and installed have been as large as 13 feet (4 m) or greater in diameter and to depths in excess of 260 feet (80 m).

Jan 1, 2018

The green field site is one that has no history of mining and as such it presents the designer with a blank canvas, on which any number of drill and blasting options can be drafted. No matter which mining method is selected all technology and experience will need to be acquired from outside sources, applied quickly and produce the right results. North Limited, in joint venture with the Sumitomo Group (20 per cent), have developed AustraliaÆs first block cave mine at Northparkes in New South Wales, Australia. This innovative and large scale mining project was taken from a green field site in November 1993 to a fully commissioned block cave mine in December 1997. NorthparkesÆ Endeavour 26 mine is now producing at a rate of 3.9Mt per annum from a 27Mt ore block. Prior to 1993 no history of mining activity existed at Northparkes. The rock had never been blasted and many questions were raised about how it would behave. While it was clear that the Endeavour 26 (E26) orebody contained geotechnical properties appropriate to block caving, the blasting methods required to establish a block cave mine had never been used in Australia and no designs were available. The joint venture partners had no prior experience with block caving and it was immediately apparent that this blasting technology would have to be acquired from foreign sources and applied to the unique local conditions. Conceptual designs for the block cave drill and blast were first drafted in 1994, first issued for drilling in December 1995 and first blasted in January 1996. 470 km of drill metres and four million tonnes of rock were blasted to complete the undercutting project by September 1997. This paper will provide those developing new drill and blast projects with an inside view of how one small technical team solved many design challenges to successfully construct AustraliaÆs first block cave mine under strict quality controls and ambitious time constraints.

Jan 1, 1998

By Richard E. Thill

The Bureau of Mines' Oil Shale Data Bank (OSDB) was created in 1976 to serve as a centralized source for the storage, retrieval, and dissemination of technical literature, patents, and information on research projects in oil shale. Thousands of bibliographic references, patents, and research projects relating to the mining of oil shale have been identified, abstracted, and indexed according to selected keyword topics. The resulting data bank listings are contained in three sections, each with a separate keyword breakdown for use in rapidly identifying references pertaining to a specific subject. All references cited in the OSDB were published prior to an established cut-off date of May 1, 1981, when a redirection of Bureau of Mines programs resulted in the loss of project funds and the subsequent phasing-out of data bank operations. ACKNOWLEDGMENTS The oil shale data bank listings are the result of a team effort of the project staff. The contributions of Jimaleen Jansma for keypunching, information acquisition, and data entry, and John Brandenburg and Sandra rake for keywording and information acquisition are gratefully acknowledged. Appreciation is expressed to the staff members of the Smithsonian Science Information Exchange, Washington D.C. for their cooperation in supplying data on recent research projects in oil shale for inclusion in the OSDR listings. Appreciation is extended also to the staff of the Gallegos Research Group for assisting with computer services to obtain the final printouts and transfer of files onto magnetic tape.

Jan 1, 1982

By J Webster-Brown

The Tui Mine is an abandoned Pb-Zn mine giving rise to water quality problems in the Te Aroha region of Coromandel, New Zealand. When sampled in September 2002, for example, both the Tui and Tunakohoia Streams draining the mine site exceeded ANZECC (2000) water quality guidelines for aquatic life protection (Cu, Cd and Zn) and recreational quality (Cd). Based on trace metal mass flux (kg/yr) from parts of the mine site, the principal pathways by which Cu, Zn and Cd contamination reach these streams have been identified as:the tailings dam leachate,the diverted stream water from above the dam,the drainage from Adit 5 (which accounts for 95 % of Zn and Cd contamination in Tunakohoia Stream), andto a lesser extent, run-off from waste rock piles below Adit 4 level. Of the various remediation options, which have been proposed for the site, the following are identified as providing the best protection for the Tui and Tunakohoia streams:stabilising the tailings dam embankment and capping the embankment and tailings,constructing and/or cleaning out engineered diversion drains around the perimeter of the tailings dam to divert surface water away from the tailings dam, andinstalling bulkheads within Adit 5. A formal postal survey of the people of Te Aroha (66 respondents from 230 surveys) indicated that their priority was that the site be made safe for the public to visit, and used for recreation. As soil samples in potential recreational areas of the mine site, significantly exceeded guideline values for Cu, Pb, Zn, Cd and As, soil removal or capping clearly also needs to be part of a remediation plan. Development of the site as a historical/ecotourism area was viewed favourably, as this may encourage more visitors to the Te Aroha area as well as educate local residents.

Jan 1, 2003

By C. W. Davis

During the fiscal year 1935-36, the Ore-Testing Section has been active in carrying out a program designed to attain the objectives that have been set up for it. For the Purpose of standardizing important testing methods, an attempt has been made to develop a rationalized scheme for ore testing, starting with preliminary investigations to determine the physical and chemical properties of the ore, following this with a logical selection and trial of processing tests to find out how the ore may be most effectively treated, and concluding with a discussion of what interpretation may be placed on the results in terms of plant design and operation. A selection of Procedures that appear well-suited to the ore-dressing problems under investigation is included in the following paper of this report so that other experimenters may be enabled to verify our findings and to offer criticisms and suggestions for improving our practice. A tentative scheme for the evaluation of flotation reagents is being investigated, and some progress has been made in a study to determine the significance of small-scale testing. These projects have required 899 analyses. Papers on these and others on ore testing, such as testing for amalgamation and for cyanidation, will be included in future annual reports.

Jan 1, 1937

By C. W. Davis

During the fiscal year 1935-36, the Ore-Testing Section has been active in carrying out a program designed to attain the objectives that have been set up for it. For the purpose of standardizing important testing methods, an attempt has been made to develop a rationalized scheme for ore testing, starting with preliminary investigations to determine the physical and chemical properties of the ore, following this with a logical selection and trial of processing tests to find out how the ore may be most effectively treated, and concluding with a discussion of what interpretation may be placed on the results in terms of plant design and operation. A selection of procedures that appear well-suited to the ore-dressing problems under investigation is included in the following paper of this report so that other experimenters may be enabled to verify our findings and to offer criticisms and suggestions for improving our practice. A tentative scheme for the evaluation of flotation reagents is being investigated, and some progress has been made in a study to determine the significance of small-scale testing. These projects have required 899 analyses. Papers on these and others on ore testing, such as testing for amalgamation and for cyanidation, will be included in future annual reports.

Jan 1, 1937

By Mark Davis

As a follow-on to previous investigations, reduced treatment levels for the optimum fire retardant/preservative system were evaluated. An impregnation of 3.5 lbs/ft3 of Fyreprufe followed by 3.5 mils of Albi 107A plus an Albi 144 top coat provides adequate flammability and flame spread protection. However, there is a significant loss in compressive strength at this retention level, particularly parallel to the grain. A pilot-size pressure impregnation cell was installed for use in treating larger quantities of wood. Based on the optimum fire retardant/preservative treatment system - Fyreprufe/ACC impregnation followed by Albi 107A/144 intumescent paint - a model treatment pro¬cess was developed, capable of handling 3 million board feet per year. Associated annualized costs per thousand board feet (K bd. ft.) for treating 12" x 12" timber were calculated to be: Impregnation: $-63.00/K bd. ft. Coating: $112.00/K bd. ft. A literature search was conducted to identify materials and techniques suitable for a localized stench warning system for heated mine timbers. Based on this review, a number of stench warning concepts were developed. Those based on surface coating were given a preliminary laboratory evaluation.

Jan 1, 1982

In-pit crushing and conveying (IPCC) is being increasingly considered as an alternative to traditional truck-shovel mining methods. The move towards IPCC is driven by a number of factors including the potential to reduce greenhouse gas emissions, the availability of skilled labour and the need to increase extraction rates to levels that present significant challenges to traditional methods.When considering the relative performance of IPCC and truck-shovel methods, the outcome can be inadvertently impacted by either the use of different simulation approaches, or techniques that do not adequately model the processes in sufficient detail.A simulation approach is proposed that models both IPCC and truck-shovel using the same software platform and is capable of functioning at a wide range of resolutions from life-of-mine scale through to second-by-second asset tracking level. The simulation framework also holds models of processing equipment and hence the mining simulations can be extended to gauge the impact on downstream plant.The approach, known as mine-process operational simulation (MPOS), can be tailored to the level of information available and hence the type of study required, ie order of magnitude, prefeasibility, feasibility, or detailed design.Using information from block models and a range of detailed equipment and process models, MPOS can span major system discontinuities, typified by the mine-plant interface, to allow the estimation of final mine and plant product specifications.

Dec 6, 2010

R. C. BUCKETT (Lake View and Star Limited) : At the outset I should like to add my congratulations to those already extended to Mr..Norwood on his excellent paper, which has given us all an inspiration to strive further to improve our plant recoveries. In some respects this paper has left us so little to discuss without considerable time spent on. further research work. At all points one is met by a baffling array of facts which leave one feeling hesitant to speak.The careful and methodical way in which Mr. Norwood went along step by step until all channels of research presenting themselves were tested to his own satisfaction leaves me with but a few comments to make. Particularly striking to me is the explanation of the residual gold values in calcines by recrystallization of haematite and here is a line to be attacked by future studies. This will be mentioned again later.Particularizing on the paper, the first point that struck me was the method of change of pyrite through to the final haematite. I have never been able to satisfy myself that a sample taken from various positions along a roaster when cooled, as described on p. 397, represented a fair sample of the conditions at that point, but I must confess that I have not found a substitute that did satisfy me.However, the following figures are illuminating... But to fill dry a receptacle of known volume with calcines, as described by Mr. Norwood, gives the following apparentspecific gravities:

Jan 1, 1940

By Robert W. Yokom

As the search for new sources of energy and minerals leads to more remote areas of the country - and the world - the need to plan for adequate housing and community facilities for the construction and operations workforces and their families takes on an importance equal to the mining and processing facilities themselves. A corollary to the need for planning is the increasingly crucial need for development companies to devise effective strategies for dealing with the local communities impacted by these projects. Experience has amply demonstrated the high price to be paid for failure to learn this lesson, a price measured in lost productivity, confrontation with local communities, labor turnover, mental health and other social and eocnomic problems. In Sweetwater, Wyoming, a new industrial activity caused the population to double from 18,000 to 36,000 between 1970 and 1974. During that period industrial productivity fell 25 to 40 percent, cost overruns on the principal new industrial facility exceeded 33 percent, annual employee turnover rates climbed above 100 percent, the local mental health clinic workload increased nine times and complaints to the local law enforcement agency increased 60 percent.

Jan 1, 1981

A record $19.7 billion in minerals was produced by United States industries in 1963. This was some $800 million above the previous high established in 1962. Preliminary statistics compiled by the U.S. Bureau of Mines show that most metals, nonmetals, and fuels gained both in value and volume of production. The 1963 total represents the largest value increase since 1956 and continues an upward trend begun in 1959. Product.ion and value of all mineral fuels rose, with anthracite registering a remarkable 20% value increase. Nonmetals advanced 591 in value, gains exceeding losses by 213 to 1 among individual commodities. Heavier industrial demand and the settling of labor difficulties were among the factors contributing to increased output of such materials as iron ore, bauxite, molybdenum, lead, and zinc, which accounted for most in€ the growth in metal output. Silver prices continued to rise and, as a result, production value of that metal gained 132,.

Jan 2, 1964

By Hyung Jeek Kim, Jongmin Joo, Jonguk Kim, Jai-Woon Moon, Kyeong-Yong Lee

"Co-rich ferromanganese crusts (Fe-Mn crusts) distributed on seamounts in the western Pacific are potential economic resources for cobalt, nickel, platinum, and other rare metals in the future. Evaluation and selection of a mining site can be established based on abundance and grade of Fe-Mn crusts in the site as well as topography that should be smooth enough for mining operations. Therefore, acquisition of shipboard echo-sounding and acoustic backscatter data are prerequisite to the selection of potential mine sites in addition to visual and sampling operations. Acoustic backscatter data can be used to locate crust-covered areas on a regional scale with the understanding of acoustic properties of crust through its correlation with visual and sampling data.During an expedition that took place from January to March 2014, KIOST collected geophysical and geologic data to assess the resource potential for Fe-Mn crusts on three seamounts (guyots) in the Western Pacific. In OSM11, one of the three surveyed seamounts, three camera tows were performed to observe the distribution of Fe-Mn crusts on the summit and slopes of the seamount. Although sediments of various thicknesses generally cover most of summit region of OSM11, several regions with high backscatter signals occur on the periphery of the summit. The occurrence of Fe-Mn crusts, observed during the camera tows, on those high backscattered regions suggests that the backscatter signals of shipboard multi-beam sonar can reflect changes in the geology of the seafloor from sediment layer to Fe-Mn crust deposits. The Fe-Mn crust deposited around the summit region is worthy of notice because of its topographic characteristics, including shallow depth, flat or gentle inclined surface, and smooth relief, which are more suitable for mining operation compared to the flanks of seamount."

Sep 1, 2014

By William E. Souder

The behavioral accident simulator (BAS) is a computer program that can be used to simulate accident situations. It demonstrates how the potential to have an accident grows or diminishes as a result of changes in various environmental, organizational, and behavioral factors. It calculates the number of fatalities that may result from various conditions and graphically displays these data. The BAS is useful for studying systems of accident causes, for demonstrating the various ways to diminish fatalities, and for training employees. This Bureau of Mines report provides the detailed instructions needed to use the BAS.

Jan 1, 1988

By G. F. Kuncir

The analysis described herein evaluates the Bureau of Mines Program for Advancing Mining Technology - Oil Shale in terms of the economic benefits which may be derived for the Nation as a result of its successful research and development efforts. On the basis of postulated oil shale production scenarios, benefit-cost ratio indicators are computed for the program elements as they apply to surface, underground, and modified in situ oil shale mining systems. Eight value indicators are used to measure the Program's beneficial impact on the future oil shale industry in relation to planned research and development costs. These are: capital cost savings, operating cost savings, labor savings environmental quality maintenance cost reduction, reduction in production costs, byproduct production benefits, total production benefits, and additions to recoverable reserves. Program costs are aggregated from 1974 through 1987 and major benefits are accrued from 1982 through 2040. Both cost and benefit streams are discounted to mid-1975 present value.

Jan 1, 1977

By Eugene Frey

"INTRODUCTION The Iron Mountain deposits were examined in the summer of 1943 by engineers of the Bureau of Lanes, and a diamond-drilling project was set up under the Strategic Minerals Program. Actual drilling operations, under the supervision of a Bureau engineer, commenced November 9, 1943, and were completed on November 1, 1944. When the Bureau began detailed exploration of the Iron Mountain deposits, the Federal Geological Survey participated. Dr. I. W. Newhouse, of the Survey, and Dr. A. F. Hagner, of the Wyoming Geological Survey, were assigned to the investigation.ACKNOWLEDGMENTSIn its program of exploration of mineral deposits, the Bureau of Mines has as its primary objective the more effective utilization of our mineral resources to the end that they make the greatest possible contribution to national security and economy. It is the policy of the Bureau to publish the facts developed by each exploratory project as soon as practicable after its conclusion. The Mining Branch, Lowell B. Moon chief, conducts preliminary examinations, performs the actual exploratory work, and prepares the final report. The Metallurgical Branch, R. G. Knickerbocker, chief, analyzes samples and performs beneficiation tests. Both these branches are under the supervision of Dr. R. S. Dean, assistant director.With respect to this report, acknowledgment is made to S. R. Zirrmerley and F. T. Allsman, Bureau of Mines, Salt Lake City, Utah, who supervised the work of this project."

Nov 1, 1946