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By J. A. McAllister, H. G. Iverson, K. C. Dean

"INTRODUCTION During the course of the investigation of the occurrence of manganese deposits in the western United States, laboratory studies of concentration were conducted at the Salt Lake City station on a sample of ore from the Lake Valley mines of the Newalpitt Fluorspar Corp. of Deming, N. Mex. The ore was reported to be representative of the type that would be mined for mill feed. The sample tested was found to be amenable to beneficiation by ore-dressing methods for the production of products that, when sintered, assayed over 44 percent Mn.At the beginning of the investigation of manganese-ore beneficiation in December 1940, the only product marketable to Metals Reserve Company was ferrograde manganese grade B, the requirements for which follow: Mn, min., 48 percent; Fe, max., 7 percent; Si02, max., 10 percent; P, max., 0.18 percent; Al203, max., 6 percent; Zn, max., 1 percent, Al2O3,Later the specifications were modified gradually. As of May 15, 1943, manganese products were acceptable if they contained over 35 percent manganese and less than 3 percent zinc and 1 percent phosphorus. Prices were based upon material containing 48 percent manganese, 6.0 percent iron, and 11 percent silica plus alumina. Premiums were paid for manganese content in excess of 48 percent and iron content below 6 percent, penalties being imposed upon products containing less than 43 percent -manganese, or more than 6 percent iron, or more than 11 percent silica plus alumina. The specifications for commercial manganese further required that maximum particle size be 12 inches and that, 75 percent of the product be coarser than 20-mesh. Therefore, fine material such as table and flotation concentrates had to be nodulized or sintered. In addition, oarbcnate manganese ores were not acceptable unless calcined."

Feb 1, 1948

By M. MacLaughlin, J. Whyatt

A case study is presented that relates statistical descriptions of joint sets to the distribution of local wedge failures along the crest of a catch bench at the Yellowstone Talc Mine. The fracture sets and bench width were mapped by teams of geological engineering students from Montana Tech under the direction of Dr. Mary MacLaughlin. The students analyzed the fracture data, conducted physical property tests, and used a beta version of a NIOSH program “Bwedge” to predict the distribution of surviving bench widths. In the course of this analysis the students developed evidence of software performance issues that, unfortunately, frustrated their analysis. These have now been addressed and a full analysis completed. The analysis confirms the validity of the student mapping program and provides insight into the effects of blasting and excavation practices on the bench. It also provides a tool for exploring the pattern of bench crest failure that would result from variations in both bench geometry and blasting practices.

By G. C. Reed, J. A. Herdlick

The Blackbird district, Lemhi County, Idaho, has long been recognized as a potential source of cobalt and copper. Exploration of the early discoveries in the area was largely discouraged by the comparatively low grade and small size of the known ore bodies, the slight demand for cobalt, and the lack of adequate roads throughout the region. Recent advances in the field of alloy metallurgy culminated in a steadily expanding demand for cobalt. This demand was finally accentuated to critical proportions in 1940 by worldwide rearmament programs and by the threatened disruption of foreign imports by submarine warfare.

Feb 1, 1947

By O. W. Terry

The Skene mine, in the Elizabeth District, Illinois, produced lead are from 1901 to 1907. Three exploratory holes drilled just north of the mine were said to have penetrated 40 feet of good zinc are. During the summer of 1944, the Bureau of Mines drilled check holes close to what appeared to be two of the three old holes. They also drilled two holes to the south of the mine and one into the core of the deposit. Results of the investigation are given in this report.

Jan 1, 1948

By Robert S. Sanford

The demand for aluminum for military use during World War II called for an expansion of aluminum production in the United States A large part of the bauxite (the normal ore of aluminum) consumed in this county comes from Netherlands Guiana, South America. During the war, enemy activities were at times a serious threat to the flow of bauxite to the United States. The need for aluminum. stimulated the investigation of domestic deposits of bauxite and emphasized the wisdom of studying other aluminous materials, such as high-alumina and diaspore clays, to determine their possible use as aluminum ores. The occurrence in Pennsylvania of high-alumina flint clays and nodular diaspore clays has been known for many years. Several companies are mining these high-alumina, low-iron (less than 3 percent Fe2O3) clays and using them for the manufacture of refractory brick. Most of the production has come from Clearfield County, but clay deposits arc known also in Cambria, Centre, Clarion, Clinton, Indiana, Jefferson, Somerset, and Westmoreland, Counties.

Jan 1, 1949

By D. C. Dahlin

The Bureau of Mines conducted laboratory batch beneficiation tests on samples from four potential platinum resources in southeastern Alaska to concentrate platinum and other precious metals. Thin Investigation was done as part of the mission of the Bureau to insure an adequate supply of minerals to meet the Nation's needs. Petrographic studies and beneficiation methods including gravity concentration, froth flotation, and magnetic separation were used to determine mineral association and to attempt to concentrate the platinum values with a primary mineral value such as chromite, copper sulfide, or magnetite. A high-graded sample from the Salt Chuck copper sulfide deposit yielded the platinum-group metal concentrate; the maximum grade attained was 0.04 oz Pt and 1.5 oz Pd per ton of high-grade copper sulfide concentrate. The other samples yielded low-grade primary mineral concentrates with low platinum-group values, and/or the platinum-group metals did not concentrate with the primary mineral value.

Jan 1, 1981

Apply state-of-the-art monitoring and computer systems technology to remotely monitor geostructural data and evaluate ground conditions in near real-time. Background Recently, the coal mining industry has progressed dramatically from a labor-intensive industry to highly mechanized and automated systems achieving significantly higher production rates. In underground longwall coal mines, production and face advance rates have increased by almost tenfold in the last 15 to 20 years. With increasingly high advance rates, geologic anomalies which affect rock mass quality are encountered more frequently, far exceeding the current rate at which ground control information can be processed and analyzed. As a result, mine operators find themselves with insufficient time or resources to cope with the rapidly changing ground conditions. To keep up with the technological advancement in mining and the associated ground control problems, the Bureau of Mines is conducting a multi-phase research pro¬gram to implement a computer-assisted Ground Control Management System (GCMS). Research is ongoing at present, but when completed the system will be designed to 1) monitor and evaluate data on rock properties, geologic conditions, and rock mechanics data from underground sensors in near real-time; 2) interpret the analyses to evaluate the interaction between various critical ground control parameters; 3) assess the structural integrity of the mine; and 4) determine failure modes and provide recommendations for control measures, design modifica¬tions, and alternative support procedures. The system will be expanded into its full capability during various phases of this research program.

Jan 1, 1991

By Launa Mallett, Charles Vaught, Jr. Brnich

This paper introduces a technique for incorporating employee participation into the prevention component of a contingency plan. Companies sometimes focus so much energy on response that they forget to put resources into the basics of emergency prevention. The training program discussed here was designed to make employees part of the prevention system. Examples of training materials from the program are provided, a sample method for introducing risk assessment to employees is shown, and a strategy to address limited training time using short videos is explained. Methods for tailoring the training to any worksite and for specific risks are also included. The program is being designed and tested by the Pittsburgh Research Laboratory/NIOSH and employees of an underground coal mine. Examples are taken from the implementation of the program at the mine during the summer and fall of 1998. Results of the program evaluation and lessons learned during the implementation are discussed.

By J. A. Lamonica

The Bureau of Mines studied a pulsation damping device designed to smooth pulsating flow in personal respirable dust samplers. The effect on the pulsation dampener efficiency of six parameters was investigated, as follows: Volume, diaphragm elasticity, diaphragm area, center orifice area, inlet-outlet orifice area, and geometry (LID ratio). The results indicate that volume pre-dominates in determining snubber efficiency, while the other parameters become important at small volumes. Geometry has no effect on snubber efficiency. Criteria for an efficient pulsation dampener construction were obtained.

Jan 1, 1971

By Lars Osen

The Bureau of Mines investigated (1) the effect of torsion on yield and ultimate strengths of bolts when the torsion is applied first and tensile load is applied independently of torsion and (2) various methods of increasing the tension-torque ratio and/or narrowing the data spread of the tension-torque relationship. A special torsional attachment was fabricated to attach to a universal testing machine to independently subject rock bolts to combined tensile and torsional loads. It was found that initially installed torsion is nullified during tensile loading and the tensile yield and ultimate strengths are not significantly reduced. Lubricating various components of a bolt assembly or using hardened washers will improve the tension-torque relationship during conventional installation; however, the torsional load is not nullified during this type of loading. Hence, a bolt is subjected to a combined stress throughout the loading cycle; the yield point will thus be lowered compared with the pure tensile yield if care is not taken during installation to stay below the torsional yield.

Jan 1, 1966

By H. K. Sacks

The Bureau of Mines has improved a mine dust incombustibles analyzer originally developed at the Bartlesville Energy Research Center (BERC). This analyzer provides quick, accurate analysis of the percentage of incombustible material present in dust samples taken from mine ribs, roof, and floor so that costly overdusting may be eliminated while still maintaining a proper level of incombustibles. The changes being effected on the present design of the BERC model IV rock dust analyzer should simplify its operation and calibration procedures, resulting in increased accuracy.

Jan 1, 1976

By E. P. Youngman

The mining law of May 16, 1884, is still the basic mining legislation in Smeden. To satisfy a demand for a revision of the entire mining law, special commissions have been at work for a number of years; but present indications are that the work will require several more years for its completion. The changes contemplated would affect mainly the relations between the nine operator and the landemer, as the present law, according to general opinion, tends unduly to jeopardize the landowner's right in favor of the miner. The socialist party desires additional changes, especially in the direction of giving more direct control of the industry to the State, a control that it now seems to exercise through individual agreements with mining companies. Its control of the Lapland iron mines comes through its sharing the ownership with the Luossavaara-iirunavaara Altb. In this instance, the Government should be Considered as a private commercial body, since the agreement with the company

Apr 1, 1933

By Ray J. Holmquist

"INTRODUCTION The Copper King or Red River copper mine was examined on December 13, 1942, by the Bureau of Mines at the request of Richard Kelly of Santa Fe, N. Mex. The examination was made to determine whether the expenditure of funds for rehabilitation work necessary to make the workings accessible for examination would be warranted.As a favorable report was made, the workings of the Copper King mine were opened and sampled under the direction of the author. The portal of the Copper King adit was opened first. Considerable rehabilitation was necessary in the first 50 feet of the workings, but the remainder of the drifts and crosscuts were sufficiently open to permit surveying and sampling.An attempt was made to open the Waterbury atilt, which was reported to be about 30 feet east of the Copper King portal, and to crosscut the ore body nearly to its southern border. However, slide rock and mine dumps had completely obscured the portal of this adit, and no opening into it could be found or made.Work on the project was started on September 27 and vas completed on November 6, 1943."

Apr 1, 1947

By Richard F. Hewlett

Use of digital computers makes possible a more efficient and complete analysis of data from a mineral deposit . This computer program was written and used during an investigation into the efficiency of methods of computing grade and tonnage of ore , wherein it was necessary to make repeated computations involving different combinations of data . This investigation was part of a continuing program of sampling methods research at the Bureau's Denver Mining Research Center.2-4 This program is designed to compute tonnage and average grade for 40 cutoff grades using either the statistical or polygonal methods . tational rate is from 200 ( input bound ) to 1,400 assays per minute , depending on the use of either individual ( one assay per card ) assay- interval length or

Jan 1, 1963

By W. D. Ryan

Industry must be made to realize that "Safety First" means just that - safety first. The miner must realize that safety first takes precedence over earnings. The employer must realize that safety is the first consideration, and is not to be subordinated to profit-making. Neither employee nor employer is justified in adopting the principle of safety first with reservations; that is they will practice safety first only so long as they think that it does not interfere with earnings or profits. This paper proposes to demonstrate that suberdinating safety to possible profit is short-sighted and that over an ex- tended period of time it dres not result in increased profits or earnings. An employee through disregard of safe practice may receive an injury that will cause him a loss of earnings if, indeed, he is net killed or permanently in- capacitated. If permanently incapacitated any compensation he may receive is very likely to be wholly inadequate as compared with probable earnings if the accident had not cccurred. The employer, upon his part, will find that the burden of compensating his injured employse will far exceed the outlay of money necessary to maintain a reasonable program of safety in his mine or plant. The mine foreman is one of the most important factors in the matter of mine safety. A vigilant and competent mine foreman, once he has established the confidence of the employees in his ability as a foreman, can be of invalu- able assistance in promoting mine safety, for through him and his assistants the employees may be made to cooperate. Every employer should remember, then, that the soluction of the foremen and their assistants is one of the most important matters connected with the work of establishing the maximum amount of safety in his mine. Everyone connected with the mining industry must be made to realize that there is to be no back-sliding and no let-up in safety work; that no matter how dry and tedious the routine may seem it is absolutely essential and justi- fied for both humanitarian and economical reasons. Efficient safety effort pays dividends in actual cash to both employer and employee. About 50 per cent of underground accidents in coal mines take place at the working face where the miners dig and load the coal. Approximately 17 per cent of coal-mine fatal accidents are the result of underground haulage. Face and haulage accidents can and will be reduced materially if the individual miner takes all precautions necessary to protect himself and if the management

Jun 1, 1930

By W. J. Boone, Will E. DeVaney, Lowell Stroud

This report is the fifth in a series presenting equilibrium vapor - liquid data for helium- bearing natural gases . It covers a 0.41 - mole - percent - helium natural gas that may be processed in the Department of the Interior's longrange helium conservation program . A Bureau of Mines phase equilibrium apparatus was used to obtain 139 samples of equilibrium vapor and liquid phases at 85 experimental conditions at temperatures from 0 ° to -299 ° F and at pressures from 100 to 500 psia . An appendix covers phase data at 100 , 200 , and 300 psia and at temperatures from -125 ° to -275 ° F for the dehydrated gas containing its original concentration ( 0.2 mole - percent ) of carbon dioxide , and the effect of a preliminary hydrocarbon trap upon subsequent vapor - liquid compositions .

Jan 1, 1964

By Paul W. Jeran

Subsidence over a series of longwall panels undermining sloping terrain in southwestern Pennsylvania was monitored to verify the Bureau of Mines subsidence prediction model for the northern Appalachian coal region. Comparison of the field data to model output shows close agreement. Vertical movements over each panel ceased with the mining of the adjacent panel. Horizontal movements were significantly affected by topographic slope. The distribution of horizontal strains over each panel were similar, with a zone of compression occurring over the center of each panel. The zones of compression were flanked by zones of tension toward the rib. The magnitude of the tensions were affected by the slope. The strains developed at the completion of each panel were not significantly altered by the mining of subsequent panels.

Jan 1, 1988

By F. W. Wessel

Manganiferous carbonate slates of the Cuyuna range, which are part of the unoxidized thin-budded iron formation, represent a large potential source of manganese. This report details recent bench-scale research by the Federal Bureau of Mines in applying mineral-dressing techniques to these materials in order to investigate their potential uses. Work outlined in the report was directed toward the production of concentrates usable as iron-blast furnace feed, but an equally important objective might have been to furnish an enriched feed for extractive processes for recovering manganese. Flotation concentrates were prepared that contained 11.1 percent manganese, 27.8 percent iron, and 12.2 percent silica, with recoveries of 73 percent of the manganese and 48 percent of the iron. Calculated analysis for a simulated sinter suggests a product containing 16.0 percent manganese, 40.2 percent iron, and 17.6 percent silica, with 31 percent recovery of the dry weight of the ore. The silica in the flotation concentrates was due to quartz and iron silicates. Substantial quantities of the iron silicates (stilpnomelane and smaller amounts of minnesotaite) were present in the slate, and the need to reject these minerals limited the recovery of iron. The sintered flotation concentrate would be usable as ferruginous manganese ore for iron blast-furnace feed because of its favorable manganese silica ratio. The unsintered flotation concentrates, representing 45 percent of the feed weight and containing manganese enriched in the ratio of 1.6 : 1, also could be used as feed to processes for extracting manganese.

Jan 1, 1961

By Owen W. Terry

During the summer of 1943 the Bureau of Mines conducted an investigation and program of churn drilling on the McIlhon and adjoining Pearson land in the Mineral Point district of Iowa County, Wis. Sixteen holes, aggregating 1,570 feet .of bore, were completed. The work was undertaken as part of a general investigation of the zinc-and lead-producing area of southwestern Wisconsin at a time when great effort was being made to increase the production of Metals important to the war program. The Bureau's drilling program supplemented a previous drilling pro-gram conducted by the Vinegar Hill Zinc Co., and demonstrated the presence of a strongly mineralized zone at relatively shallow depths.

Jan 1, 1948

By Raymond F. Helinski, Linda J. McWilliams, Sean Gallagher, Thomas R. Battenhouse, August J. Kwitowski, John R. Bartels, Dean H. Ambrose

This report examines the boom arm vertical speed for roof bolting machines to study a moving boom arm appendage at different speeds during different work scenarios. The goal of this study is to determine the impact of the appendage speed on the likelihood of the operator's hand, arm, head, or leg making contact, such as touching the moving appendage. The overall research goal is to reduce workers' risks to injury from exposure to underground mining machinery. Accident investigation reports from the Mine Safety and Health Administration do not usually contain enough information to aid in studying this problem, and lab experiments with human subjects are not feasible because of safety issues. As an alternative, researchers used a unique computer simulation model that uses a virtual human, vision tracking, and generates random virtual human motions and risky work behaviors. By using specialized software to simulate the computer model, researchers accurately identified potential hazards of tasks where it is not possible to perform experiments with human subjects. Results of a frequency distribution analytic approach show that, regardless of other variables, contact incidents were always greater when the boom was moving up, always greater on the hand, and always greater or the boom arm part of the machine. The reason why the subject experiences more contacts when the boom arm is moving up rather than down is that more risky behaviors occur during drilling and bolting when the boom is ascending. Results of a cross-tabulation analytic approach show that the 25th-percentile operators experienced more contacts than other operator sizes and had most of their contacts during a boom speed of 13 in/sec. The hand-on-boom behavior during drilling and bolting tasks experienced more contacts than other work behaviors, and both tasks had most of their contacts during speed 13 in/sec. The 60-in seam experienced more contacts than other seam heights and had most of the contacts during speed 16 in/sec. For univariate logistic regression models, seam height is the most important predictor of the probability of a contact. However, a multivariate logistic regression model predicted contacts are more likely with the both-knee work posture in the 60-in seam, a 25th-percentile operator compared to a 55th-percentile operator, and speeds 16 and 22 in/sec compared to 7 in/sec. Results of a survival analytic approach suggest that controlling the boom speed is the most important factor in determining the risk of an operator making contact. Based on the data collected, boom speeds greater than13 in/sec result in a substantial increase in risk to the roof bolter operator making contact. Speeds less than or equal to 13 in/sec are associated with a more modest relative risk of making contact, which represents a decrease in potential hazard. Virtual operator's response time has little effect on the number of contacts experienced. The mining industry can use the information in this study to reduce the likelihood that roof bolter operators will experience injury due to contact with a moving roof bolting machine's boom arm.

Jan 5, 2005