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By Ana Chiquini, Clayton V. Deutsch

The most common approach used in the mining industry for mineral resources modeling is to estimate the grades using ordinary kriging and report the recoverable resources based on this deterministic estimated model. Mineral resources calculated with kriging are a smooth representation of the actual distribution of grades and do not provide an assessment of uncertainty. Unlike kriging, simulation reproduces the variability of the grades in the mineral deposit and provides an assessment of uncertainty. Reporting mineral resources directly on high-resolution simulation results would assume perfect knowledge of the grade at the time of mining and selectivity at the scale of the data. There will always be uncertainty left at the time of mining, so assuming perfect knowledge of the grade in the future is incorrect. There are two concerns when geostatistical simulation is used for resources modeling: the information and the mining selectivity effects. A new framework for resource estimation is proposed with two separate modules to address those concerns. The information effect is accounted for by anticipating the additional production data that will be available at the time mining to guide the destination for the mined material. The mining selectivity effect is addressed by mimicking the grade control procedure to get mineable dig limits at a chosen selectivity, represented by a minimum mineable unit size. In addition to a prediction of recoverable resources that will be closer to the material mined in the future, the framework proposed provides an assessment of local and global uncertainty for risk management.

May 26, 2020

By R. S. Dean

As set forth in the decision of the Trail Smelter Arbitral Tribunal, dated April 16, 1938 This Tribunal is constituted under and its powers are derived from and limited by the convention between the United States of America and the Dominion of Canada signed at Ottawa, April 15, 1935, duly ratified by the two parties and ratification exchanged at Ottawa, August 3, 1935 (hereinafter termed "the Convention") . . . The duty imposed upon the Tribunal by the Convention was to "finally decide" the following questions: (1) Whether damage caused by the Trail Smelter in the State of Washington has occurred since the first day of January 1932, and, if so, what indemnity should be paid therefor? (2) In the event of the answer to the first part of the preceding Question being in the affirmative, whether the Trail Smelter should be required to refrain from causing damage in the State of Washington in the future and, if so, to what extent? (3) In the light of the answer to the preceding Question, what measures or regime, if any, should be adopted or maintained by the Trail Smelter? (4) What indemnity or compensation, if any, should be paid on account of any decision or decisions rendered by the Tribunal pursuant to the next two preceding Questions? In this decision reported to the Government of the United States of America and to the Government of the Dominion of Canada, the Tribunal answered the first question in its entirety and reserved decision on the other three questions in accordance with the following extract from their decision

Jan 1, 1944

THE Synthetic Liquid Fuels Act. (30 U.S.C., 321-325, and amendments) became law April 5, 1944, and a period of intensive research and development in this field was begun by the Bureau of Mines. As part of this program, bulletins were published on pressure hydrogenation.3 the Fischer-Tropsch synthesis,4 anal oil shale.5 The Bureau also has published a short bibliography on coal gasification,6 mostly of a theoretical nature. Because coal gasification is prerequisite to either the Fischer-Tropsch or coal-hydrogenation processes, publishing this sizable collection of technical information in this form will be valuable. The material will be presented in three parts, as follows: I. United States Patents. II. United Kingdom Patents. III. Other Foreign Patents. The domestic patents for this bulletin were collected between 1953 and 1955.

Jan 1, 1960

This: symposium was sponsored by the Bureau of Mines, U.S. Department of the lnterior, in order to critically examine the state-of-the-art of sulfide flotation chemistry and to define current and emerging problems that should be emphasized in future fundamental research. The topics covered through invited papers include both reviews and recent research results in the areas of thermodynamics of reagent-mineral interactions; collector adsorption processes; the effects of solid-state point defects on flotation; activation and deactivation phenomena; the electrochemical role of oxygen in sulfide flotation; environmental problems in flotation; and selective flocculation of fines. Papers riving perspectives on flotation research in relationship to our national mineral requirements and the relationships between industrial flotation research and academics are also presented. An edited summary of the symposium follows the papers.

Jan 1, 1980

By N. A. C. Smith, E. W. Dean, W. A. Jacobs, H. H. Hill

Fractional distillation is the most important process in the commercial refining of petroleum. The same procedure, conducted on a small scale, is the basis of a number of analytical methods of wide application in the petroleum laboratory. The Bureau of Mines has studied apparatus and procedure for the distillation analysis of petroleum, and this report is presented as a record of developments up to the present time. The work is incomplete, but the extensive information that has been obtained to date is made available as a guide in handling laboratory distillation problems. The analytical distillation of petroleum is commonly made to determine range of boiling points or to separate the oil. into fractions for detailed examination, or both. When only one of these two ends is sought the procedure involved is notably simpler than when, as is more common, information is required regarding both boiling range and properties of fractions. Moreover the degree of minuteness of measurement and the accuracy of the data required from analytical distillations differ considerably. Often the simplest sort of comparative figures are satisfactory; other tests require complicated and highly tedious procedure. No one distillation method is universally applicable, and it is impossible for anyone group of investigators to foresee all the different kinds of requirements that may occur in the industry.

Jan 1, 1922

By E. H. BURROUCHS

This bulletin is the third of the series of yearly petroleum bibliographies being published by the Bureau of Mines. The two preceding, Bulletin 149 and Bulletin 165, were for the years 1915 and 1916, respectively. In arranging the references the same general scheme has been followed, but as in those bulletins, several changes and additions have been made in the classifica.tion, the more important being in the classes " Development and production " and "Refining and refineries." German periodicals for 1917 were not procurable and references to articles in those and in other foreign journals that were not available have been credited to the sources from which they were procured.

Jan 1, 1920

By T. A. Rickard

The writing that is effective is woven with a fine texture into an agreeable pattern; it is free from knots, loose threads, and stray fluff. The instrument that weaves this literary fabric, whether it produce a homely sock or a lordly tapestry, a simple story or a learned 'Itreatise, is a disciplined intelligence, as sure as a steel needle, as precise as a swift loom. The simile breaks down at this point, for the product of the pen is instinct with the human spirit and therefore transcends in beauty anything made by a mere machine. If words are to be woven into eloquent meaning, they must be well knit. Upon the relation of words to each other and of groups of words to other groups, known as phrases, clauses, and sentences, depends the success of writing as a means of trans¬mitting thought from man' to man. To be understood beyond question, you should know not only what your words denote but how to build your sentences; you must not only choose your words aright but construct your sentences properly. A sentence is a combination of words that makes complete sense; it says something about something. ' A clause is a subordinate sentence or a sentence within a sentence. A phrase is a group of words without a predicate; it makes sense, but not complete sense. For example: I shall wait for a few minutes before I go home: The whole statement is a sentence; "I shall wait" and "before I go home" are clauses; "for a few minutes" is an adverbial phrase. The orderly arranging of words and of combinations of words is called `syntax'; and from the original Greek form, ouvaeis (suntaxis), is derived the Greek name for an editor,

Jan 1, 1931

By R. O. Neal, G. St. J. PERROIT

As natural gas is a waning resource in many places, increased interest has attached to the use of gas for the manufacture of carbon black. Because of a large number of requests for information on the subject, the Bureau of Mines has undertaken a detailed study of the carbon-black industry, covering the mechanical details of commercial methods, with the purpose of increasing the recovery of carbon black by such processes. A study has been undertaken of the economic factors governing the carbon-black industry, the uses and properties of carbon black, the dE)velopment of more Itccurate methods of testing carbon black, microscopic examination of different grades of black, physicochemical study of methods' of mQ.nufacture now in use, and research on new methods of manufacture. Part I of this paper covers the engineering and economic side of the industry; the other phases of the investigation which have been under the direction of G. St. J. Perrott, of the Pittsburgh station.of the United States Bureau of Mines, are discussed in Part II.

Jan 1, 1922

By Hal M. Lewers

IN the past few years and especially since the beginning of World War No. 2, gold has attained a new, important. and critical place in the international scene, and in world affairs. In the past, as far back as history records, most wars have been waged for the purpose of acquiring it from someone else by conquest. But now, the most titanic struggle of all time is being waged with the avowed purpose of not only destroying it, but of destroying all that it stands for and represents. A tradition dating back to ancient Rome, affirms that battles are fought by men with weapons, but wars arc eventually won by gold. The validity of that tradition is now being subjected to its major test. Hitler has proclaimed that in his new world order, the work dollar or reichsmark, a beautifully engraved paper currency representing only a theory of value, based on unit of work and production, will become the supreme medium of world exchange, and that gold eventually will he valueless and obsolete.

Jan 1, 1942

By M. Salimov, J. Sattarvand

The conventional visualisation method of remote equipment is through the installation of one or more cameras on the machine, and sending a live feed to the operator’s flat display. However, the performance of the teleoperation can be enhanced using better visualisation through virtual reality (VR). This paper presents the process of the design and manufacturing of a robotic platform that will be used in the next phase of the project for a VR-assisted teleoperated excavator. The robot consists of a loading boom and arm arrangement installed on the undercarriage of a CAT300-9D. All hydraulic cylinders are replaced with electric actuators, and crawling motors are substituted by electric motors. The pieces of the boom and the arm, as well as the bucket were designed in Autodesk Inventor, and manufactured from aluminium sheets using a desktop and CNC machine. Parts are joined by pins and welding as needed. An Arduino-based control system is developed for the robot, and motor controllers are used to convert the power commands from the microcontroller to the high-amperage actuators. The control system is capable of communicating with a wireless Play Station controller to operate remotely. The manufactured robotic excavator is planned to be utilised in multiple autonomy research projects.

Sep 1, 2021

By Mary Ellen Bruce Large

"In partnership with California Department of Transportation (Caltrans), Federal Highway Administration (FHWA), and with support from International Association of Foundation Drilling (ADSC), Deep Foundations Institute (DFI) organized a workshop on quality assurance (QA) practices for acceptance of post-grouted drilled shafts in conjunction with DFI’s 40th Annual Conference on Deep Foundations. The 1½-day workshop was held on October 15-16, 2015 at the Oakland Marriott City Center in Oakland, CA.Post-grouting, in the context of this workshop and report, refers to the alternative design and construction of base-grouted drilled shafts wherein a grout distribution system is installed during construction and used to grout the base under pressure after the drilled shaft concrete has gained adequate strength, resulting in a stiffer axial-compression load-displacement relationship and additional possible ground improvement effects.The primary goals of the workshop were to•?Identify and summarize the state of the practice for design, construction, inspection, verification, acceptance criteria, reliability and performance of post-grouting.•?Identify gaps and needs in quality assurance that should be addressed for successful use of post-grouting.This report is structured to follow the workshop program: workshop presentations outlined the state of practice and views from owners, engineers and contractors on acceptance of post grouting methods for drilled shafts; and subsequent workshop discussions attended by a small invited group of participants focused on identifying areas of agreement and disagreement on post-grouting best practices, acceptance criteria, design and verification procedures, and inspection requirements. A partial list of attendees of the open and closed sessions is provided as Appendix A, and copies of presentations are included as Appendix B.FHWA and Caltrans are the primary audiences for this report, and its content will be used to develop a roadmap for deploying the findings into policy and practice. The secondary audience is the broader industry group, and the report content will be disseminated in a variety of formats."

Jan 1, 2016

By Mary Ellen Bruce Large

"INTRODUCTIONIn partnership with California Department of Transportation (Caltrans), Federal Highway Administration (FHWA), and with support from International Association of Foundation Drilling (ADSC), Deep Foundations Institute (DFI) organized a workshop on quality assurance (QA) practices for acceptance of post-grouted drilled shafts in conjunction with DFI’s 40th Annual Conference on Deep Foundations. The 1½-day workshop was held on October 15-16, 2015 at the Oakland Marriott City Center in Oakland, CA.Post-grouting, in the context of this workshop and report, refers to the alternative design and construction of base-grouted drilled shafts wherein a grout distribution system is installed during construction and used to grout the base under pressure after the drilled shaft concrete has gained adequate strength, resulting in a stiffer axial-compression load-displacement relationship and additional possible ground improvement effects. The primary goals of the workshop were to•?Identify and summarize the state of the practice for design, construction, inspection, verification, acceptance criteria, reliability and performance of post-grouting.•?Identify gaps and needs in quality assurance that should be addressed for successful use of post-grouting.This report is structured to follow the workshop program: workshop presentations outlined the state of practice and views from owners, engineers and contractors on acceptance of post grouting methods for drilled shafts; and subsequent workshop discussions attended by a small invited group of participants focused on identifying areas of agreement and disagreement on post-grouting best practices, acceptance criteria, design and verification procedures, and inspection requirements. A partial list of attendees of the open and closed sessions is provided as Appendix A, and copies of presentations are included as Appendix B.FHWA and Caltrans are the primary audiences for this report, and its content will be used to develop a roadmap for deploying the findings into policy and practice. The secondary audience is the broader industry group, and the report content will be disseminated in a variety of formats."

Jan 1, 2016

By Kenneth K. Humphreys

INTRODUCTION What is automation? Why automate? Webster's New Collegiate Dictionary defines automation as "the automatically controlled operation of an apparatus, process, or system by mechanical or electronic devices that take the place of human organs of observation, effort, and decision." This definition gives an implied answer to the second question, "Why automate?" Automation, automatic control devices, and process control equipment receive their justification in supplementing or replacing manpower, which results in decreased operating costs. In the past, processes were operated with the minimum amount of instruments needed merely to guide operators. Processes were manually con- trolled by the operator on the basis of simple temperature, pressure, flow, and level indications on a panel. Today the tendency is to design a new plant to operate in a fully automatic manner according to a preset pro- gram utilizing a minimum of manpower. In addition to this direct cost reduction in manual labor, increased equipment capacity results from uniformity of flow and uniform control of process variables. This control eliminates or minimizes surges and permits equipment to be operated at or near its ultimate capacity and, for a given material throughput, permits the use of smaller process equipment. Automatic control, therefore, be it in the field of coal processing or in any industrial field, is simply a problem of economics. Control equipment is justified in terms of its contribution toward increasing productivity, increasing profit margins, or producing a new and salable product at a profit. Instruments and control devices can be divided into two general groups: (1) units which measure and (2) units which both measure and control a process variable.

Jan 1, 1979

By Branch of Editorial Services

"The Bureau of Mines was established in the public interest to conduct inquiries and scientific and technologic investigations concerning mining and the preparation, treatment, and utilization of mineral substances; to promote health and safety in the mineral industries; to conserve material resources and prevent their waste; to further economic development; to increase efficiency in the mining, metallurgical, quarrying, and other mineral industries; and to inquire into the economic conditions affecting those industries. The organic act of the Bureau, as amended by Congress and approved February 25, 1913, made it the province and duty of the Bureau of Mines to ""disseminate information concerning these subjects in such manner as will best carry out the purposes of this Act.""In accordance with this directive, the Bureau reports the findings of its research and investigations in its own series of publications and also in articles that appear in scientific, technical, and trade journals; in proceedings of conventions and seminars; in reference books; and in other non-Bureau publications. The number of these reports, the wide range of subjects they cover, and the variety of mediums in which they appear make the kind of list and index presented in this special publication both necessary and valuable. This issue of the Bureau of Mines List of Publications and Articles describes reports and articles published during the period January 1, 1980, to December 31, 1984. It supplements the 50-year list of Bureau publications issued from July 1, 1910, to January 1, 1960;1 the 50-year list of articles by Bureau authors published outside the Bureau from July 1, 1910, to January 1, 1960;2 the 5-year lists of publications and articles from January 1, 1960, to December 31, 1964,3 from January 1, 1965, to December 31, 1969,4 from January 1, 1970, to December 31, 1974,5 and from January 1, 1975, to December 31, 1979;6 and the annual lists of Bureau publications and articles from January 1 to December 31, 1980,7 from January 1 to December 31, 1981,8 from January 1 to December 31, 1982,9 and from January 1 to December 31, 1983. 10"

Jan 1, 1985

By Willie M. NeSmith, W. Morgan NeSmith, Alan Roach

"In 2013, Augered Cast-in-Place (ACIP) piles are a mature foundation technology throughout the United States. General guidelines for the design and construction of ACIP piles are available along with numerous references for design in specific North American geologies. In fact, the current generation of contractors and geotechnical practitioners might view ACIP piles as just another deep foundation option to be considered, along with driven piles, drilled shafts and others. This acceptance has developed, however, over a 60-plus year period.The term, Augered Pressure-Grouted (APG) pile is often used when referring to ACIP piles because the piles emerged out of construction processes at the Intrusion-Prepakt firm in the late 1940s. The company’s specialty was pressure grouting and preplaced aggregate concrete. The grouting was typically accomplished by driving a pipe to a target level and then injecting grout under pressure. In some soil conditions, it was necessary to use an auger to reach the desired grouting depth. In these circumstances, the grout pipe was driven beside the auger and grout was pumped as the auger was withdrawn. The grout pipe was then withdrawn as well. This was the genesis of the APG, or ACIP pile, and many piles were installed using this technique. The patent application, “Method for Forming Piles” was filed by Raymond Patterson of Intrusion-Prepakt in 1951, and the patent was granted in 1956. The process was eventually modified when a suitable hollow-stem auger was developed. Licenses were granted to the Lee Turzillo Contracting Company and Berkel & Company Contractors, Inc. in the late 1950s. Each of the three companies Patent, LicensesThe patent application, “Method for Forming Piles” was filed by Raymond Patterson of Intrusion-Prepakt in 1951, and the patent was granted in 1956. The process was eventually modified when a suitable hollow-stem auger was developed. Licenses were granted to the Lee Turzillo Contracting Company and Berkel & Company Contractors, Inc. in the late 1950s. Each of the three companies coined their own terms for the piling process: “Pakt-In-Place” for Intrusion-Prepakt, “Auger Pressure-Grouted” for Berkel and “Augercast” for Turzillo. Over time, “Augercast” was frequently used as a generic term for the system. The installation of these piles was, and still is, a highly nuanced process; “contractor dependent” is a term often seen today. Intrusion-Prepakt, Berkel and Turzillo all had personnel who were part of the original group that developed the system and who appreciated the craftsmanship involved in forming sound piles."

Jan 1, 2013

The value of processed materials of mineral origin was estimated to have exceeded $297 billion in 1991. U.S. raw non fuel minerals production in 1991 was estimated at $30.8 billion, a 5.8% decline from that in 1990. This estimate was based on data for the first quarter of 1991 (in some cases two quarters) for most of the 21 minerals that for many years have accounted for more than 95% of the industry's production value. The value of minerals production has increased in all but 4 of the last 30 years. The metals component of production value has fluctuated much more than the industrial minerals component, reflecting the greater volatility of metal prices. Employment in metal mining rose slightly in 1991, but this gain was more than offset by a decline in employment in industrial mineral mining, resulting in an overall decline of 3.0% to 164,600 workers in 1991. Prices of several major metals declined during 1991, reflecting weakness in the economy, causing some metal mines to shut down or reduce operations.

Jan 1, 1992

These proceedings consist of papers presented at Bureau of Mines Technology Transfer Seminars in August 1983 for the purpose of disseminating recent advances in mining technology in the area of large mobile surface mining equipment safety and health. The Bureau of Mines conducts several of these seminars each year in order to bring the latest results of Bureau research to the attention of the mining industry as quickly as possible.

Jan 1, 1983

By Fred W. Brackebush

In underground stopes that require more than minimal support, backfill is almost universally used. The term cut and fill stopingis used in a broad sense in this section, which describes underground mining methods requiring support. Support in stopes can be classified as local or short-term and general or long-term. Local support for the back of a stope, for example, can be accomplished with rock bolts or timber stulls. General support for the walls of the stope is provided by backfill. Local support provides a safe working place for the stope miners. General support, provided by backfill, preserves the access way to the stope and prevents large scale dilution of ore. Supported methods are a set of cut and fill stoping methods using backfill for general support and various local support methods. his section is subdivided into three chapters: 19.1 Cut and Fill Mining 19.2 Excavation Techniques 19.3 Backfilling Methods

Jan 1, 2008

By Paul M. Tyler, Colin G. Fink

THE field of rare metals is so broad that progress can be reported upon many important fronts. Not satisfied with the 92 elements that Mendeleeff and his followers have accepted as legitimate, scientists are trying now to complicate matters by making new elements. Enrico Fermi announced the fabrication of "Element 93". Uranium, instead of being allowed to disintegrate slowly according to its normal habit, was bombarded with neutrons until some of them seemed to have stuck in the nucleus. To understand just what is alleged to have happened all one has to do is to line up the elements in their usual order of ascending atomic weight and imagine, as physicists do, that each atom is a little solar orbit comprising a central mass or planet about which other masses revolve like satellites. Ordinary hydrogen, being very light, consists of only one positively charged proton center, with only one positively charged electron revolving about it. Other atones are progressively more complicated until we come to uranium, which has a relatively big center and 92 particles revolving around it.

Jan 1, 1935

By Bureau of Mines Staff

Coal research and related activities in 1964 by the Bureau of Mines resulted in many advances in the production, preparation, and utilization of this valuable natural resource. Mining research during the year was marked by work on hydraulic mining, coalbed degasification, mine drainage control, mine sealing, strip-mine rehabilitation, and quenching of mine-refuse fires. Bureau research continued to produce information leading to increased safety in underground mining. Such research included roof and rib control via bolting and bonding, pressure monitoring of coal and mine rock during mining operations, and development of safety devices for detecting conditions leading to roof falls. Other safety work was continued on methane detectors, coal-dust suppression, and mine venti lation equipment and techniques. Mine explosion and explosives research, mine equipment and materials, safety rule modernization, and safety education and training of mine workmen were continued. Coal storage and preparation work in 1964 ranged from freezeproofing of lignite for rail shipment, through washability studies of coals and washing equipment, to research on new ways to remove ash and sulfur from coal. Electric power production, which ,accounts for a major portion of the market for coal, received further study. Unique power generation systems, inc luding coal-burning gas turbine and megnetohydrodynamic generators, were intensively investigated. Conventional power systems were improved through continuation of work on furnace performance, powerplant stack gas purification, and engineering and boiler water service.

Jun 1, 1965