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By Gary E. Slagel

The year was 1974. The event - the United States Congress was embroiled over what issues should be included in the proposed national surface mining law. The question - what should be done with underground mines? The leading bills ultimately addressed the environmental impacts associated with underground mines including provisions to protect the surface from subsidence impacts. Amid the fears that this subsidence language might discourage underground mining, sponsors of the bill were asked to explain the meaning of the provision that read "to prevent subsidence to the extent technologically and economically feasible." Was this an attempt to limit mining that caused planned and controlled subsidence? Former Deputy Director of the Office of Surface Mining, Dean Hunt, reviewed some of these historical events in a 1985 presentation before the Eastern Mineral Law Foundation. He reported that in 1974 Congressman Morris Udall took the floor to respond to these concerns expressed by other members of Congress and the industry. Mr. Hunt cited Congressman Udall's July 10, 1974 Congressional Record statement: "The House bill contemplates rules 'to prevent subsidence to the extent technologically and economically feasible.' The word prevent led to fears expressed by the Secretary of the Interior Morton, that the effect would be to outlaw longwall mining, with its obvious subsidence ... in fact the bill's sponsors consider longwall mining ecologically preferable and it and other methods of controlled subsidence are explicitly endorsed." Further, the report that accompanied the front-running bill, HR11500, provided the following clarification on the issue of subsidence prevention: "It is the intent of this section to provide the Secretary with the authority to require the design and conduct of underground mining methods to control subsidence to the extent technologically and economically feasible in order to protect the value and use of surface lands. Some of the measures available for subsidence control include: (1) leaving sufficient original mineral for support; (2) refraining from mining under certain areas---or (3) causing subsidence to occur at a predictable time and in a relatively uniform and predictable manner. This specifically allows for the uses of longwall and other mining techniques which completely remove the coal." It is clear from the preceding statements that Congress considered the removal of all the coal and causing subsidence in a predictable and uniform manner to be equal to or better than leaving support coal and causing no subsidence. While the actual provision in the bills talked of preventing subsidence, a subsequent exception made it clear that the real intent was to control it. This is evidenced in the specific planned subsidence language that appeared in the bills and ultimately in Section 516 (b) (1) of PL95-87, the Surface Mining Control and Reclamation Act. It reads: "...adopt measures...to prevent subsidence ... except in those instances where the mining technology used requires planned subsidence in a predictable and controlled manner..." In spite of this historic record that supports controlled subsidence, something has been lost in the implementation. The primary focus by many regulators over the past few years has been on the "prevent" aspect irrespective of mining method being used. This has appeared to change the original intent of Congress from one of controlling subsidence to one of minimizing damage. The objective of this report is to review some of the current regulatory issues that impede full extraction mining and offer some suggestions on possible ways to deal with these issues.

Jan 1, 1986

By P. R. Clifford

Phosphogypsum is a byproduct of the manufacture phosphoric acid. There are approximately one billion tons of phosphogypsum stored in stacks in northern and central Florida. The Florida Institute of Phosphate Research (FIPR) is investigating potential uses of phosphogypsum. These include using phosphogypsum as a road base material, as a soil amendment in agriculture, as a daily cover in landfills, and as a construction material. The results of this research will be presented and will be discussed in light of regulatory barriers to the use of phosphogypsum.

Jan 1, 2002

By J. Wiese

Recently the operating philosophy at concentrators processing platinum bearing ores has started to move from a recovery dominated system to one in which the production of high grade concentrates at the expense of some recovery would provide greater benefits in the further upgrading of the platinum group minerals (PGM). The low grades usually obtained are associated with the presence of naturally floatable talcaceous gangue minerals in all PGM ores. Polysaccharide depressants such as guar gum and carboxymethyl cellulose (CMC) are used to improve the grades of the concentrates. Recent testwork has shown that the use of high depressant concentrations can prevent any naturally floatable gangue from reporting to the concentrate. The only gangue present in the concentrates would be due to its entrainment in the froth. Under these conditions much higher grades can be achieved. The sulphide minerals themselves, however, become susceptible to depression at high depressant concentrations. This work examines how the recovery of sulphide minerals in two Merensky ores was affected by the type and concentration of the collector in the presence of high depressant concentration (500 g/t) and that the response of the sulphide minerals was also dependent on the type of depressant used (guar or CMC).

Jan 1, 2009

By Brendan Reilly, Jon Isaacson, Paul McDermott

Kenny/Shea JV is constructing the water intake tunnel for the new Elm Road Generating Station, a supercritical coal-fired power plant in Oak Creek, Wisconsin, being built by Bechtel Power Corporation. The intake tunnel system consists of a temporary mining shaft, pump house and intake channel riser shafts, and four lakebed intake shafts. An 8.33 m diameter, 2,800 m long TBM mined rock tunnel is being constructed to connect the shafts. The intakes are located 2.4 kilometers offshore in Lake Michigan. The shafts and tunnel are being constructed in glacial tills and Silurian Dolomite. The estimated tunnel completion is December 2007.

Jan 1, 2007

By C. D. Elifrits, N. B. Aughenbaugh

Introduction Federal and state laws enacted to regulate coal mining and the accompanying public concern about the adverse effects that mining might have on land use have focused much attention on the subsidence of the land surfaces over underground mines. Some questions asked are: • Will abandoned mines subside in the future even though they have exhibited no surface adjustment to date? • If so, when will subsidence take place? • Can a specific surface area be affected by subsidence more than once? • What surface form will the subsidence feature take? • Is there any way to predict when subsidence will occur and end? An attempt is made here to address these questions insofar as it is possible with available data and experience of evaluation of subcritical extraction conditions. Mining that results in subsidence features can be classified as supercritical, subcritical, and critical with respect to the minimum span lengths of the worked-out rooms (Fig. 1). A complete basin will not develop fully immediately over subcritical conditions because the span lengths of the entries are less than the critical dimension (Wardell, 1983). Passageways, entries, and room-and-pillar panels are all included in the subcritical category. Because of the short span lengths, subcritical mining conditions tend to be stable over the life of the mine unless adverse geologic conditions exist (Gray et al., 1974; Dunrud, 1976). Various roof control and support procedures are employed to maintain entry stability during mining. Little information exists concerning the time factor of subsidence over areas of subcritical extraction. Data that have been collected relate to longwall mines, whereby the cavity sizes are designed large enough to induce caving behind the working faces so that complete subsidence at the surface occurs within a short period of time. The UK's National Coal Board (1975) has reduced the enormous amount of data it has collected to empirical correlations and has published these correlations in its Subsidence Engineers Handbook. The handbook states that "None of the foregoing remarks applies to pillar and stall working," with respect to the section discussing the time factor of subsidence caused by longwall mining (National Coal Board, 1975, p. 40). To understand and evaluate how time relates to subsidence above room-and-pillar mines, one must first recognize how mine cavities deteriorate and fail. The propagation of failure to the surface must then be studied, and, finally, the failures that are manifest at the surface in the form of depressions accompanied by both compressional and tensional movements must be investigated. Failure of mine cavities Any cavity beneath the earth's surface represents a condition of nonequilibrium and tends to close with time. Failure of cavities in a subcritical mine can be classified as failure of the roof, failure of the floor, failure of the supports (pillars, cribs), and elastic rebound of the rock. One mode of failure may dominate, but generally combinations of the four will occur. Also, initial instability of geologic materials and structural features and in situ stress may be unknown factors that can contribute to cavity failure. Roof failure is the most obvious opening stability problem in most operating mines. The bridging capabilities of the roof rock are dependent on the rock's material strength, geologic discontinuities, and reaction to humidity changes in the air of the mine. This type of failure may vary in magnitude from gradual flaking to massive roof falls. Mine floor instability can be manifest in the form of a general heave over a broad area or of individual pillar punching. The weaker and thicker the immediate floor material, the more prone a mine is to experience floor problems. Water seeping into an area can soften the underclay, reduce its bearing capacity, and precipitate failure of support for the overburden.

Jan 8, 1986

By Richard Weinstein, Richard Snoby

There are many advantages to upgrading coal with dry jigging technology. The most obvious is the lack of process water, which eliminates the need for fines dewatering and slurry confinement. Dry jigging eliminates the clean coal moisture penalty associated with wet processing. Particulate emissions are virtually nonexistent due to inclusions of fabric dust collectors on all modern dry jig plants. Because of the environmentally friendly nature of dry jig plants, installation permits are often measured in days, not months. There has also been a fundamental advance in dry jigging efficiency. All of these advantages have renewed the coal industry’s interest in dry jigging. But air jigging is not right for every application. There are limitations due to particle size, particle shape, moisture and near gravity content. This article explores the evolution of dry jigging. It reviews parameters important for determining the suitability of dry jigging. It also compares historical performance data as measured by imperfection, against results from modern dry jigging technology. The article also presents data from modern dry jig installations.

Jan 1, 2007

By Jim Owens

The methodology of quarrying changed significantly in the Indiana limestone industry in the 60 years between Sept. 11, 1941 and Sept. 11, 2001. The former was the date of the Pentagon groundbreaking ceremony, while the latter was when the building was damaged by American Airlines Flight 77. So too, though to a lesser degree, did the machinery and methods used to fabricate the stone. The rededication ceremony on Sept. 11, 2002 marked the end of the Phoenix Project, as the rebuilding effort was named. The story of this remarkable project illustrates what the American construction(and Indiana limestone) industry can accomplish when working toward a common goal.

Jan 1, 2005

By C. Bise, A. Seal

Excessive noise has long been a hazard in the coal-mining industry. Studies conducted during both the mid-1970s and the mid-1990s consistently show that hearing hearing loss within the mining industry persists, in spite of regulatory requirements and sampling technology advances. When MSHA’s new health standards to protect miners from hearing loss took effect in September 2000, the potential developed to re-evaluate sampling approaches with regard to noise-source hazards, such as task-based methods. This paper describes results from a Penn State research project currently being conducted at an underground coal mine. Each occupation was reviewed, and a list of tasks or processes performed by each was generated. Traditional personal noise dosimetry, static sound pressure levels, and equipment sound mappings have been performed. Job tasks indicating the greatest levels of daily noise exposure and contributions to noise dose have been identified and will be discussed.

Jan 1, 2001

By S. Möllerherm

"The evaluation of data and information provided by the existing traditional indicators in sustainability assessments is most important. Therefore the Institute of Mining Engineering I from the RWTH Aachen University developed indicators and an assessment system for the mineral raw materials industry on operation, company and sector level on behalf of the Federal Ministry of Economics and Labour (Bundesministerium für Wirtschaft und Arbeit, BMWA) and the Federal Institute for Geosciences and Natural Resources (Bundesanstalt für Geowissenschaften und Rohstoffe, BGR). In the course of the development of indicators for the raw materials industry quality indicators on different levels of the sustainability assessment procedure have been identified and developed. The following paper describes some of the results focussing on the development and integration of quality indicators into sustainability assessment systems."

Jan 1, 2005

By R. C. Burton

One of the major problems encountered with recirculatory breathing apparatus presently used by mine rescue teams is that the inspired air becomes uncomfortably, and often dangerously, hot. This is also true with self-rescuers. It is well known that man can tolerate very high dry-bulb temperatures if the wet-bulb temperature is low, but not vice- versa. The maximum tolerable, wet-bulb temperature is about 42 °C (108 °F). A continuously inhaled wet-bulb temperature above this value can cause irreversible damage to the throat and lung tissue, and wet-bulb temperatures close to it cause extreme discomfort (1) and seriously retard the capability of the man to perform useful work. A theoretical analysis, combined with experimental results, has shown that it is the carbon dioxide absorbent that is the major cause of high wet-bulb temperatures of the inspired air in the Siebe Gorman Proto 4, and in the Draeger BG 174 apparatus, both of which are used by rescue teams on South African mines (2). In the Proto 4 apparatus, the absorbent for the carbon dioxide is soda lime (calcium hydroxide). The German Draeger BG 174 also uses this absorbent but under arduous conditions such as in hot environments (50 °C, 122 °F), the use of an alkali absorbent cartridge is recommended which consists mainly of caustic soda (sodium hydroxide). Lithium hydroxide is used in some apparatus in the United States. It is clear that different absorbents will produce different quantities of heat and moisture for a given rate of absorption of carbon dioxide. The proportion of this heat and moisture which is transferred to the user depends upon how much can be removed from the recirculating air between the absorbent and the mouthpiece. This paper discusses the present methods of heat removal and describes the design and test results of a prototype evaporative cooler.

Jan 1, 1980

By Ralph Spickermann

UK Seabed Resources (UKSR) signed a manganese nodule exploration contract with the International Seabed Authority on 8 February 2013 for a 58,000 km2 tract on the eastern edge of the Clarion Clipperton Zone (CCZ). UKSR is a private company based in the United Kingdom and established primarily to develop the commercial potential of the CCZ deposits. This is the first of many anticipated regulatory, market and technical milestones that are requisite for (1) environmentally responsible commercial scale production of nodule derived metals and (2) generation of revenue through their sale in the global commodities market. This presentation will describe the progress made to date in this effort and an industry-based perspective on the tasks and challenges that may lie ahead.

Sep 1, 2014

By Georgy Cherkashov, Svetlana Babaeva, Tamara Stepanova, Firstova. Anna

Seafloor massive sulfides (SMS) study in the Russian Exploration Area at the northern equatorial Mid Atlantic Ridge began after signing the contract with International Seabed Authority in 2012. In order to evaluate the SMS resources in the course of exploration the major and rare metals with economic value should be determined. The evaluation is based on geochemistry and mineralogy and particularly on the type of rare metals occurrence in the SMS. As a case study research of the Semyenov cluster of SMS deposits have been conducted.

Sep 1, 2014

By R. Unger, L. Mallett

The use of virtual reality (VR) technologies to train miners is an evolving area in research and development. In July 2006, representatives of 14 international organizations met to discuss current VR-related efforts and explore ways to employ VR in the future. This paper gives an overview of the various approaches presented at the meeting and discusses directions for future implementation. An example of a training package that teaches mine map-reading skills is presented. The meeting was the first step to building collaborations for furthering VR applications for mining. Planning has begun for a 2008 meeting open to broader participation.

Jan 1, 2007

By Wijnand Dalmijn, Hans de Ruiter

Experience over the past eight years has proven that partnership and cooperation in mineral engineering education is essential to maintain programs in this field. At this moment the joint European Mineral Masters Engineering Course (EMMEC) has three programs in the areas of mining, minerals engineering and geotechnical/environmental engineering, offered by combinations of nine universities in seven European countries. About 25 companies are associated with the universities in the Federation of European Mineral Programs (FEMP) which coordinates these activities. The EMMEC has applied for recognition under the newly launched EU “Erasmus Mundus” program in which the EU makes 280 million Euro available for bursaries for non-European students and scholars.

Jan 1, 2005

By C. L. Kosmoski

The mining industry faces many workplace hazards that are a threat to human health and safety. The Bureau of Labor Statistics has found that employees in coal mining are more likely to be killed or sustain an injury or illness than workers in private industry. These injuries are also likely to be more severe (Bureau of Labor Statistics, 2007). In recent years, coal mining injuries have attained national attention due to highly publicized disasters. Despite these threats to worker safety and health, the U.S. relies on the mining of coal to meet its need for electrical power, with42% of electricity in the U.S. generated through the burning of coal (U.S. Energy Information Administration, 2012b; United Mine Workers of America, n.d.). Furthermore, the production of coal continues to increase and reach record levels every year(National Mining Association, 2012; U.S. Energy Information Administration, 2012a). For this reason, the coal mining industry must continue to find ways to protect its workers while maintaining productivity. One potential approach to protecting workers while maintaining productivity is through improving the safety culture at coal mines. In order to achieve this culture, operators, employees, the inspectorate, etc. must share a fundamental commitment to safety as a value. This type of culture is known in other industries as a ?safety culture? and can be defined as the characteristics of the work environment, such as the norms, rules, and common understandings that influence facility personnel?s perceptions of the importance that the organization places on safety. Fundamental to improving safety culture within an organization is understanding the existing safety culture; improvements cannot be made without first elucidating areas that require improvement. This manuscript details the process undertaken by researchers at the National Institute for Occupational Safety and Health (NIOSH) Office of Mine Safety and Health Research (OMSHR) to assess the safety culture at five underground coal mines across the United States. The purpose of this manuscript is to introduce the mining industry to a multi-methodological approach to safety culture assessments. Further, it is the goal of this manuscript to highlight the value of including both quantitative and qualitative methods into safety culture assessments in order to obtain the most comprehensive view of an organization?s safety culture. Because this manuscript focuses solely on the methodology implemented, data and results obtained during the five safety culture assessments will not be presented in this manuscript, but will appear in a future publication.

Feb 27, 2013

By K. Nielsen

The paper presents a brief overview of the mineral industry in Norway, followed by a description of the mineral policy and relevant legislation including the roles of the Norwegian Directorate of Mining and Geological Survey of Norway in this context. The discussion then proceeds to describe the land use planning framework on a national, regional and local level, the interaction between land use planning and the Directorate of Mining and the Geological Survey respectively, and how this impacts on the mineral industry and the exploitation of mineral resources. Some recent Norwegian examples of land use planning conflicts are also presented.

Jan 1, 2005

By H. Lyn Bourne

This is the fourth annual tabulation that gives mineral royalty information. The table presents previous information plus about two dozen new entries. In addition to the royalty information, some entries show the cost of purchased reserves. Last year's tabulation appeared in two issues, to accommodate all of the information. This year the format has been changed slightly so the table can be printed in one issue. This year's table presents the commodities in the same sequence as last year. Sand and gravel information appears first, followed by: crushed stone for aggregate; other stone; industrial sand; other industrial minerals; energy minerals (coal, oil shale, uranium); and finally metals. As always, a caveat relates to factors that influence the reserve values. The data should serve only as a general reference. The table is not intended to present an absolute scale of reserve costs. Several factors influence the value of mineral commodities. These factors include: • location and transportation costs (especially significant for most industrial minerals); • market conditions for both the commodity and the company acquiring the right to mine it; • quality or grade of the deposit as it reflects the amount of processing and beneficiation necessary to produce the finished product; • and legislative restrictions and conditions for mining a given material at a given site. These and other factors will influence reserve costs of reserves. The table shows the range of royalties and the variations in the basis of computing the fees. In a few instances, it gives the cost of acquired reserves based on purchase price and quantitative estimates of the material in place. The table lists the commodity; the location (either by state, US geographic area, or Canadian province); the cost (R for royalty and P for purchased cost); and the year in which the lease or purchase agreement occurred. The last column offers either comments or gives a footnote number for more information. The cost column requires more explanation. The units may refer to cubic yards (/yd), cubic feet (/cuft), tons (/T) (2000 lbs) or acres (/A). 1 cu yd = 0.76m3 1 cu ft =0.28m3 1st = 0.9 t7 1 acre = 0.40 ha or m2 In several cases the royalty is a percentage of the finished products, sale price and is levied against either the amount produced or the amount sold. We thank those who contributed information for the table: J. Dunn, T. Eyde, K. Loda, L. Morgan, F. Nix, H. Sorenson, and L. Williams. Several people have said they would like this to be an annual tabulation. That can happen if new information comes to the writer. What appears in the table is only a very small fraction of the cost information relative to the various commodities and the geographic areas for which there is royalty information. If you find this column of interest and possess information write or call: H. L. Bourne, c/o Neyer, Tiseo & Hindo, Ltd., 38955 Hills Tech Dr., Farmington Hills, MI 48018, (313) 553-6300. Only with new information can this become an annual and current source of reserves costs.

Jan 8, 1986

By Jon J. Indall

I. INTRODUCTION The challenge of moving the use of nuclear energy from military to civilian use was first issued by President Dwight Eisenhower in his December 8, 1953 “Atoms for Peace” speech delivered at the United Nations. Eisenhower stated: “The United States knows that if the fearful trend of atomic military build up can be reversed, this greatest of destructive forces can be developed into a great boon, for the benefit of all mankind. * * * * The more important responsibility of this Atomic Energy Agency would be to devise methods whereby this fissionable material would be allocated to serve the peaceful pursuits of mankind. Experts would be mobilized to apply atomic energy to the needs of agriculture, medicine, and other peaceful activities. A special purpose would be to provide abundant electrical energy in the power-starved areas of the world. In the 1950’s and 1960’s, the Atomic Energy Commission promoted the use of nuclear power as the answer to our nation’s energy problems. Nuclear power would provide energy too cheap to meter. The utility industry responded and numerous plants were planned with over one hundred constructed from the 1970’s to the 1990’s. Capital costs for nuclear power plants escalated due to permitting changes and public opposition, and the Three Mile Island incident caused new nuclear plant construction to cease. Today, we once again are experiencing a nuclear renaissance. Concerns over global warming and rapid projected increases in the demand for electricity have caused many nations to begin construction of new nuclear fleets. The price of uranium to fuel these reactors, which had dropped to an historical low of $7.10 in 2001, has surged to $56.00 as of October 2006. This paper will review some of the social, environmental, and government issues that are all playing a role in the resurgence of the nuclear fuel industry.

Jan 1, 2007

The 112th Annual National Western Mining Conference (NWMC) hosted by the Colorado Mining Association (CMA) drew some political heavyweights, if by voice only, into the fray of two of the hottest topics that the mining industry is currently facing ? climate change and the new energy economy. A changing political landscape in Colorado, as well as in Washington D.C., has given rise to questions about the economic future of the United States and the mining industry?s role in that future. While there has been a recent push away from traditional energy sources to a ?new energy economy? that is rich in renewable energy sources such as wind and solar, the NWMC?s agenda emphasized the role that minerals will play in new energy technologies. The conference was also full of talks about the industry?s role in reducing the United States? reliance on foreign oil and other mineral commodities. To that end, an impressive lineup of speakers were invited to attend the three-day conference Feb. 8-11, in Denver, CO. Unfortunately, Mother Nature had other plans and three of the four headliners, including Denver?s mayor and Democratic candidate for governor of Colorado, John Hickenlooper, were unable to get to the conference because of a massive blizzard on the East Coast locked them in Washington, D.C. However, with modern technology, a full auditorium heard presentations from Hickenlooper, National Mining Association (NMA) president and chief executive officer Hal Quinn and Glenn Kelly, vice president, government affairs for NMA. Republican candidate for governor of Colorado, Scott McInnis, did speak to the crowd in person.

Jan 4, 2010

By Lee W. Abramson

Performing risk analyses on tunnel projects has become common place and on many projects it is required from an owner or regulatory perspective. After the project is planned, designed and constructed, the data concerning identified risks, assumptions, costs, probabilities and mitigations is generally long forgotten and buried in some file somewhere. A study was performed comparing predicted risks versus actual events on several recently constructed tunnel projects. Probabilities and costs for selectively common risks on tunnel projects have been studied and re-evaluated. Conclusions are presented that can guide future projects and the veracity of the tunnel risk analyses performed.