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By R. G. Gürtunca

The future of the United States (US) mining industry will be affected greatly by recent coal mining disasters. These have resulted in new legislation which will have an impact on mining economic costs as well safety and health of miners. This paper discusses the changes that new legislation and regulations are making to the industry and current research that is producing technologies to make mining safer and will likely impact the future of mining.

Jan 1, 2009

By Scott Turner

We are here today to witness the graduation of 63 young men as Engineers in the mineral industries . It is an important occasion and one in which the public takes a keen interest , since this school has long been famous for the educational facilities it affords young men, and for the high professional standing of its graduates . : : : It is fitting that once each year we should pause to review the path the student has traveled , and to reflect upon the perspective opening before him as an engineer . I was invited to come from Washington to take part in this ceremony and to say something to these young graduates . In searching for a theme ," it occurred to me. that perhaps my best contribution would be to duscuss certain beliefs as to college training , deal with the situation in which the young engineer finds himself on graduation , touch on the new ideas of the social and political responsibilities of the engineer , and point out what he may expect to find in practice , and , above all , what he must do to orient himself properly in the mining profession and maintain the best traditions of our brotherhood . Let us first review your college days and see what they have done for you . I am told there are still many temptations in college . I know there used to be . Rest assured the same holds true in the professional life ahead of you. The main difference is , perhaps , that your greatest temptations in college were those offered by your teachers , who tried to entice you into realms of harder work, closer application , increased concentration , clearer thinking and better understanding , by animating your curiosity and increasing your powers of reasoning and of observation . In other words , here you have carefully and systematically been decoyed toward finer and loftier things . Do not expect that similar helpful influences will greet you on every side in your professional life . Often quite the contrary is the case .

Oct 1, 1930

By Carl Belser

Approximately 30 million pounds of tungsten trioxide in the form of ferberite concentrates have been shipped from Boulder County. Since 1940, the production has varied considerably, being affected by the emergency needs of World War II and the Korean conflict. During World War II, attempts to stimulate production were made by the Metals Reserve Company by stabilizing the price for a specified period, the Reconstruction Finance Corporation by small mining development loans, and the Bureau of Mines and the Geological Survey, who cooperatively explored some of the district by surface and underground core drilling. During the Korean conflict and continuing through the first half of 1954) tungsten production was being stimulated by a Government-gauranteed price and by financial assistance loans under the Defense Production Act of 1950 to qualified operators of properties that have merited exploration. This combined program has increased production in Boulder County from about 1,900 pounds in 1949 to an estimated 383,000 pounds of tungsten trioxide in 1953. The 1953 production came from 67 properties. One of the problems confronting producers is the need for improved beneficiaton methods. Ores from the area have not been amenable to flotation concentration and gravity methods have resulted in poor recovery, often less than 70 percent.

Jan 1, 1955

By B. W. Moore

The U.S. Bureau of Mines investigated the separation of heavy rare-earth elements (REE) in an ion-exchange process. An ion-exchange column consisting of two sections, a loading section and a separation section, provides high levels of REE loading and good REE separation with an expected processing cycle of less than a month, while current ion-exchange technology requires more than 5 months. A different resin is used in each section: sulfonic resin in the loading section and iminodiacetic resin in the separation section. The separation section is further divided into two segments: the first conditioned with NH4 and the second with acid. Erbium is loaded onto both segments of the separation column as a retaining ion. Bands of mixed REB eluting between separated bands of pure REB were recycled directly to the column. Without mixed-band recycle, over 80% of the REE eluted from the column was separated into fractions with 99% purity of each element; with such recycle, the percentage of separated elements can be increased to around 90%.

Jan 1, 2010

By Terry S. Cory

This report is a comprehensive summary of the results of the propagation measurements program conducted for the US Bureau of Mines under Contract H0366028. Data was gathered in the MF frequency range from a cross sample of six mines representative of the industry having typical wireless requirements. From the raw data which was gathered, a logical method of data reduction is presented which culminates in a set of average attenuation characteristics for all mines visited. These characteristics define a typical MF wireless system when the communication range requirements are known. Direct through-the-earth propagation and the range enhancement mechanism due to coupling on and off conductors are evaluated and related to the planning of a typical wireless MF communications system.

Jan 1, 1977

By Mark R. Pettitt

The charter of this investigation was to identify and promote the application of noise control technology to future longwall mining machinery. Intensive noise and vibration data were acquired on a typical longwall shearing machine, and the highest noise levels were shown to radiate from the cutter drums. Shearing machine cutter drum noise control techniques that take advantage of the nature of the dynamic forces generated during coal cutting were developed. These include both structural redesign and force isolation techniques. A reduced noise cutter drum was developed that achieved a 5 to 6 dBA system noise reduction at the operator's position. Its operational performance was verified by a six-month long in-mine test. It was evident from the data that additional noise reduction could be achieved by treatment of the shearing machine hydraulics. Noise control of secondary sources was also investigated. A method of reducing full or empty stage conveyor noise (and continuous miner conveyor noise) by 5 to 10 dBA was demonstrated through isolation techniques. Underground mine durability testing, however, is yet to be demonstrated.

Jan 1, 1986

By Dennis R. Dolinar, Christopher Mark, Gregory M. Molinda

Despite more than half a century of experience with roof bolting, no design method has received wide acceptance. To begin to improve this situation, National Institute for Occupational Safety and Health (NIOSH) conducted a statistical study of roof bolt performance at a number of mines throughout the U.S. Case histories were collected from 37 mines with a variety of roof bolt types and patterns in a wide range of geologic environments. Performance was measured in terms of the number of roof falls that occurred per10,000 ft of drivage. The study found that roof falls are rare when the roof is strong and the stress is low, even with light roof bolting patterns. The focus of this paper is on the more difficult conditions, where the roof is weaker and/or the stress is higher. Analysis of the results led to guidelines that can be used to make preliminary estimates of the required bolt length, capacity, and pattern. The guidelines are based on the depth of cover (which correlates with stress) and the roof quality (measured by the Coal Mine Roof Rating (CMRR), and the intersection span. Another contribution is a formula for estimating the horizontal stress level in the eastern U.S. coalfields as a function of the depth of cover. The design guidelines are currently being implemented into a computer program called Analysis of Roof Bolt Systems (ARBS).

By Ronald M. Hays

The Duluth Gabbro Complex in Northeastern Minnesota possibly contains a significant domestic copper resource and the nation's largest nickel resource. Exploration has discovered large low-grade copper-nickel (Cu-Ni) deposits between Hoyt Lakes and the Boundary Waters Canoe Area (BWCA). The mining and processing of Cu-Ni will have environmental, economic, and social impacts. The purpose of this study is to relate major environmental, economic, and social considerations to various aspects of Cu-Ni extraction. An open pit and two underground (block caving and open stoping with backfilling) models were developed to generate information on the impact of Cu-Ni extraction. Important considerations having environmental, economic, and social impacts (luring various aspects of Cu-Ni extraction are identified and defined. These aspects are exploration, development, mining, beneficiating, smelting, transportation, and termination of operations. Considerations are grouped into the general categories of site, industrial, energy, climatic, resource, water, air emission, waste disposal, employee, tax and royalty, transportation, and community considerations. Cu-Ni extraction in Northeastern Minnesota presents major environmental, economic, and social risks. Decisions are required on trade-offs between adverse and beneficial impacts. The approach used in this study assists in assessing environmental, economic, and social impacts. It will aid in the examination of potential and projected short-term and long-term advantages and disadvantages and will aid in the development of Minnesota's Cu-Ni resource for the maximum benefit to society.

Jan 1, 1974

By N. T. Lowe

This Bureau of Mines publication presents salient deposit information in abstract form on 119 principal mineral deposits in the State of Nevada. Commodity coverage addresses 17 critical and strategic commodities that appear to have commercial production potential in the State. The core of the deposits described is taken from those properties evaluated d under the Bureau of Mines Minerals Availability Program (MAP); additional deposits are included to provide a more complete coverage. Institutional and infrastructural factors affecting mineral development are also discussed.

Jan 1, 1985

This volume contains a series of papers describing research conducted by the Bureau of Mines to develop or improve equipment and systems that satisfy the communication requirements of miners doing work related to rail, belt-conveyor, trackless, and hoist haulage systems.

Jan 1, 1977

By Albert L. Toenges

[The i~ ortance o~ S3~e, fdequnt, nQ economical tr~n~po~t~t on 8ys~em Th~a bee~ e~~~~siz8d by the introduction of mechanical loading in co 1 mines, pa.rticula:c y \'r~ e::-e ~o?oile loaciine; ~ac~ine!;j rrre u .... ed. This papar i tr_e . eco:1d or' ?. ~eries deGcribi 1{) t:;'~~11>ort:ltion G stems et1-p oyed in mech3JlizeG. f!lincs. Progre,-s ?. epo~ t J...2.t deal t ~~tirel.: ,'Ii th the l:se of rail .laulagr £or c;atl:erine tran~ortc;tion, ailc, in t-!is paper 'Ii 11 be i acuss d c .icilY rub"col'-t? ro ~ t:tto::"ing as Ie _ as ani:naJ., con-",reyor, an ot.he~ systems of rnil gatheri?1.g. ~ho l)urpo~e of this invosti-gation is, as outlined in Progress ,~ort 1, to studT . Q analyz0 v rious systems nov.: in. u"'e El.I1d to derivQ cor..cl :cicn .... tllcrcfrom.]

Jan 1, 1941

Rock property tests were performed on NX-size diamond drill core from the roof, floor, and coal from the longwall mining section of Federal No. 2 mine, West Virginia. The purpose of these tests was to determine the engineering properties of the various strata as part of a ground control study of the longwall operation. The following tests were performed: 1. Uniaxial compressive strength, Young's modulus, and Poisson's ratio 2. Triaxial compressive strength 3. Brazilian tensile strength 4. Modulus of rupture 5. Specific gravity Thirteen boxes of core delivered to the University on April 1, 1974 were identified as follows: 2 PTR 1 -2 boxes of roof rock 2 PTF 1 -2 boxes of floor rock 2 PTR 2 -2 boxes of roof rock 2 PTF 2 -2 boxes of floor rock with approximately 3 ft of coal in Box 2 (designated 2 PTC 2) 2 PTR 3 -2 boxes of roof rock 2 PTF 3 -2 boxes of floor rock 1 PC 5 -1 box of coal

Jan 1, 1976

By Bill York-Feirn

The Colorado Mine Safety & Training Program (MSTP), in late 2005, completed and began distributing two new training tools; one geared to underground coal mine foremen and the other to surface aggregate employees. Through strong partnerships with MSHA, Colorado Coal Mine Board of Examiners, Colorado Mining Association and the Colorado Rock Products Association, the MSTP continues to create innovative and interactive training tools for not only Colorado, but for the national mining community. "Although we shoot and produce these materials in Colorado, it's important to us to make sure they are useful nationally," said Bill York-Feirn, MS TP Manager. The interactive DVD program "Underground Mine Foreman Certification Study Guide (Coal)," was completed in October 2005. It won the 2005 Grand Prize at the MSHA National Training Materials Competition in Beaver, West Virginia. [ ] This program is fully based upon the requirements of Title 30 Code of Federal Regulations (30 CFR) Parts 48, 50, 70 and 75 for underground coal mine foremen. It contains eight modules plus immediate access to relevant laws in the appendix. Topics covered include: Federal Law, Practical Math Skills, Mine Gases, Ventilation Maps, and scenarios addressing a variety of practical mining concerns. The DVD is designed for self-¬paced study and practice.

Jan 1, 2006

By Albert L. Toenges

[The i~ ortance o~ S3~e, fdequnt, nQ economical tr~n~po~t~t on 8ys~em Th~a bee~ e~~~~siz8d by the introduction of mechanical loading in co 1 mines, pa.rticula:c y \'r~ e::-e ~o?oile loaciine; ~ac~ine!;j rrre u .... ed. This papar i tr_e . eco:1d or' ?. ~eries deGcribi 1{) t:;'~~11>ort:ltion G stems et1-p oyed in mech3JlizeG. f!lincs. Progre,-s ?. epo~ t J...2.t deal t ~~tirel.: ,'Ii th the l:se of rail .laulagr £or c;atl:erine tran~ortc;tion, ailc, in t-!is paper 'Ii 11 be i acuss d c .icilY rub"col'-t? ro ~ t:tto::"ing as Ie _ as ani:naJ., con-",reyor, an ot.he~ systems of rnil gatheri?1.g. ~ho l)urpo~e of this invosti-gation is, as outlined in Progress ,~ort 1, to studT . Q analyz0 v rious systems nov.: in. u"'e El.I1d to derivQ cor..cl :cicn .... tllcrcfrom.]

Jan 1, 1941

By J. W. Thompson

A contract stipUlating for the delivery of quantities of phosphate rock" f. o. b. mines," and stipUlating that" while this contract is in form an absolute sale for a fixed quantity in each year, it is mutually understood and agreed that the purchase is for the buyer's consumption and not for a sale; the buyer agreeing to give to seller the refusal of any surplus over and above the actual consumption. Buyer is at liberty to increase or diminish the quantity called for in any year, to the extent of not exceeding 10 per cent; provided that the quantity to be taken shall not be less than buyer's consumption; provided further that notice of such increased or diminished demand be given seller 12 months in advance of such change," is to be construed as a contract for the sale of stated quantities of rock, deliverable in approximately equal quantities during each year for the specified series of years, subject only to be increased or diminished after specified notice in any year, where the amount taken would not be les<; than the buyer's consumption, not exceeding 10 per cent, and the contract indicating that the rock was intended by both parties for consumption in the fertilizer plant of the buyer. but the quantity to be taken was not limited by the necessities of' the plant.

Jan 1, 1916

This appendix contains the list of equipment, their corresponding number and their specifications with the quotations from the vendors/ manufacturers who can supply this equipment. The listings are arranged by process plant areas.

Jan 1, 1979

By Kenneth R. Maser

This report describes a research and development program sponsored by the United State s Bureau of Mines. The purpose of the program was to develop reusable explosion-proof bulkheads for a cross-cut emergency shelter, and to study the implementation of such bulk-heads, and the resulting shelters, as part of an emergency escape plan in a normal coal mining environment. The first part of this report reveals a number of significant conclusions regarding the application of emergency shelters. A study of the cause s of, and the conditions prevailing during a mine emergency indicate s that ideal placement of the shelter s would be midway along developing entries, and at the inter section of butt and main entries. The proper spacing of shelters is based on the travel capability of trapped miners, which is in turn dependent on the height of coal. The life of a given emergency shelter, based on an analysis of the above information, will be anywhere from 6 months to 10 years. Consequently, some shelters are regarded as "temporary?, while others "permanent?.

Jan 1, 1975

By GJ Hundman

The Multiple Unit Continuous Haulage (MUCH) System was designed to provide the capacity to continuously convey coal from the mining machine to the main haulage belt. The MUCH System has an operator who steers the lead vehicle, ever following the mining machine. All the remaining vehicles follow the path of the lead vehicle, with their conveyors automatically lining up between the lead vehicle and mine section panel belt. This is accomplished by mechanical linkages on the vehicles which are interconnected by steering bars between vehicles (patent pending). The MUCH System has an operator who steers the discharge vehicle when outby travel is required. Outby travel is just like inby, with each vehicle following the path of the preceding vehicle. Surface tests overwhelmingly indicate the "UCH System should track/retrack successfully in square pillar underground room and pillar coal mines with 18 ft. wide entries and slopes up to 10 percent. For 60 degree pillar plans the minimum entry width required is 15 ft. Surface tests also indicate the MUCH System will convey over 8 TPM of coal around 90 degree corners without excessive spillage.

Jan 1, 1983

By C. A. Geffen-Fowler

This report, sponsored by the Bureau of Mines, presents the results of an examination of the safety of the Blind Shaft Borer (BSB) shaft sinking system and an alternative modified BSB design concept in comparison to conventional shaft sinking technology. Detailed study of the two systems was also performed to identify and recommend design changes for optimum safety conditions. A comparison of the BSB systems with conventional shaft sinking was made on the basis of relative risk levels. Risk incorporates both the frequency and the potential consequence of accidents. A safety evaluation of the component operations of the two BSB systems was performed using a Failure Modes and Effects Analysis (FMEA) methodology. The results of this analysis show generally that both BSB systems are safer than conventional shaft sinking. The potential risk of conventional shaft Sinking operations could be reduced by over 30%, on the average with the use of the original BSB system, and by an average of about 10% with the modified BSB. Design change recommendations to further improve the safety of these systems include a better fire suppression system, improved man haulage systems and more compact hydraulics. An operational safety manual was also developed for the modified BSB system.

Jan 1, 1981

By Maurice Deul

This bulletin summarizes the work conducted under the Bureau of Mines methane control research program during the years 1964 to 1979. This research effort was directed toward improving existing methods and developing alternative methods of reducing the explosion hazard during mining. The research was performed in three general areas: (1) basic factors that control the emission of methane into coal mines, (2) methane control during mining, and (3) methane drainage in advance of mining. Topics discussed in this bulletin include the magnitude of the methane problem; the equipment and instruments developed; the geological, chemical and physical parameters that control the movement of methane in coalbeds; the direct method of determining gas content; the estimates of gas content from adsorption data; and methane drainage, through shafts, through horizontal boreholes, through vertical boreholes, or through slant holes. Improvements in ventilation, control of methane in gob areas, and water infusion are also discussed, as is the potential use of coalbed methane as a supplement to natural gas supplies. This bulletin provides a comprehensive source of information on the accomplishments of the Bureau&apos;s methane control research program, on the technology developed, and on the direction of further research.

Jan 1, 1986