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Develop an environmentally feasible method of mining shallow oil sands without removing overburden. Approach Oil sands are extracted through a single borehole by cutting into the sands around the borehole with a high pressure water jet, and pumping the resulting slurry to the surface. Although oil can be extracted from shallow fields by open-pit mining methods, this type of mining may create significant environmental impacts, including; (1) disruption of the surface, (2) accumulation of waste rock piles, (3) accumulation of tailings, (4) damage to the ground water quality, and (5) surface water pollution. The borehole mining system developed and successfully field tested by the Bureau of Mines offers a method for extracting oil from oil sand with minimal disturbance to environmental quality. (For examples of other applications of borehole mining, see Technology News Nos. 95, 63 56, and 48.) How It Works Prior to the start of mining operations, baseline conditions for ground subsidence and ground water quality are established at the test site so that the degree of subsidence and changes in ground water quality can later be determined. Oil sands mining is conducted using the Bureau of Mines borehole mining system. The borehole mining tool consists of a 12-inch-diameter pipe string and accessories capped with a three passage swivel terminated with a mining section. The mining section has an auger at the bottom. Four slurry inlet holes and an eductor are located above the auger, and a single cutting nozzle is located near the top of the mining section. The tool generates a high velocity water jet that erodes and slurrifies ores. The slurry is drawn into the inlet of the eductor which lifts the slurry to the surface where it is deposited into a slurry discharge sump. To detect evidence of subsidence, surveys of the land surface are made at regular intervals during, and until 30 days after, the termination of the mining operations. Samples of ground water from the borehole and two adjacent monitor holes are taken on alternate days during the mining operations, and are later analyzed to determine if any ground water contamination has occurred.

Jan 1, 1981

By E. O. Binyon

The Blue Metal corundum-andalusite deposit, in the Buckskin Mining district, Douglas County, Nev., was explored by the Bureau of Mines in 1945. The results of that work were presented in Report of Investigations 3895, exploration of the Blue Metal Corundum Property, Douglas County, Nev. published in August 1946. That report also describes the property in detail, giving location, ownership, history, geology, and data on beneficiation tests. Further exploration was carried on in April and Way 1947, the results of which are presented in this report. The work consisted of 175 feet of drift and crosscut, bringing the total to 398 feet of underground working, as shown in figures 1 and 2. The 23-foot drift, which was the last work of the initial project, was extended 99 feet northward along the shear zone, and three crosscuts, spaced at approximately equal intervals along the drift, were driven to country rock on the hanging and foot walls of the zone.

Jan 1, 1948

Improve the dust-control effectiveness of the Rotoclone1 dry-dust collection systems used on surface coal mine drills.

Jan 1, 1994

Reduce the dust exposure of workers in large processing buildings at mineral processing operations, using a total mill ventilation system.

Jan 1, 1994

To reduce air be respirable dust generated from emptying dry dust collectors on small truck-mounted drills used at surface coal mines.

Jan 1, 1995

By R. D. Currie

Many coal companies have a system for checking men into and out of the mine , and generally such systems appear to be perfectly sound and adequate . However , when the real test comes at the time of a mine disaster , too often the system is found to have failed , and hours and sometimes days pass before it is known how many men are in the mine and who they are . Most of the systems in use , when properly maintained , are adequate for the routine work of the mine , and some of them may prove adequate at the time of a mine disaster . All systems , however , depend upon proper supervision and strict adherence to the system .

Jun 1, 1930

By F. B. Tough

An inusual job in controlling a gas well was executed on No. 1 well, Inland Oil and Refining Co., situated on the Alkali Butte structure, Freemont County, Wyoming. The work was done by the company in cooperation with the . S. Bureau of Minos, and resulted in a fuel saving of $5,000 in one season and of a repair job estimated at $15,000, or a total of $21,000. The woll had an open flow of 6,000,000 cubic feet of gas per day with a rock pressure of 560 pounds per square inch. A string of 6-1/4 inch casing with a toothed shoe was set on the cap rock above the gas sand at 2181 feet. Then the well was shut in, the gas worked out around both the 6-1/4 inch and 6-1/4 inch strings, breaking through the ground surface at several points under the derrick. Casing troubles encountered while drilling made it unsafe to attempt Coving the 6-1/4 inch string. Moreover, it was important from the standpoint of good management to make the gas from this well immediately available for fuel in other operations and, in addition, to save the gas from wasting. An ordinary mudding and cementing job would have necessitated sitting down this well for probably two months out of a very short operating season. For these rousons it was determined to mud the well, if possible, between the 6 and 8 inch strings by pumping mud fluid through the connection from the gas clamps. The gas clamps used wore of ordinary construction with a side outlet, making them equivalent to a Braden-hoad. When the mud fluid was pumped through the gas clamp into the space between the two strings, it began to appear inside the 6-1/4 inch string. It apparently entered the well either around the toothed shoe or through a "line sawed" leak in the string and was blown out of the well as fast as it was pumped in. In order to stop the leaks, about a half a gunny sack of finely chopped bull ropa was fed with the mud between the casings as before. The hemp gathered around the valves of the mud pump to some extent, and it also stuck in the casing-head fittings a few times. An obstruction in the casing- head would be removed by permitting the woll to "blow back" for a few seconds, and one in the pump valves, by removing the valves when necessary. In two days' time sufficient hemp and mud had been pumped into these strings to kill external and internal pressure. The wall was shut in and allowed to stand over night. The next day, by opening and closing the master gate at intervals,

Mar 1, 1921

By F. E. Wormser

"Arsenic has been recently quoted at 10 1/2 - 11 cents per pound, an increase over the prevailing price of last fall, when arsenic was cents, as against pre-war prices around 4 cents is evidently a sustained demand for this material. The following statements are intended to summarize briefly some particulars regarding arsenic.Commercial arsenic is the white arsenious oxide (As203). This is the form in which it is generally marketed, as the uses of arsenic demand its industrial application in this form. Arsenic as an element finds rather restricted use in the hardening of lead shot, ere it is to some extent replacing the use of antimony, while white arsenic is employed in a variety of manufacturing processes, chief of which is the manufacture of insecticides and sprays. The poisonous nature of most arsenic compounds, the commonly known ones being paris green and lead arsenate, and its relative cheapness, make arsenic a material suitable for this purpose. The stimulation of agriculture during the war greatly increased the demand for arsenical insecticide. Glass making consumes a large amount of arsenic as it has been impart increased brilliancy to the glass. Crude commercial arsenic is often used to kill weeds along railroad tracks. Arsenious oxide is used also for preserving hides, while the disulphide, AS2S2), finds an application in dehairing hides for the finest grade leather, as it least affects the product. Orpiment (As233), is used in textile dyeing. Wall paints and wall paper formerly consumed considerable arsenic in the form of paris green, but this use has been largely,given up due to the poisonous nature of the dust from the product. Sodium arsenate for a similar reason, is now little used in printing where it had found application. The great objection to arsenical yes and paints is the risk of poisoning from use of the manufactured article. Sodium arsenite is the principal poisonous in¬gredient of many cattle and sheep dips. Arsenic compounds are also used medicinally."

Jan 1, 1920

By D. J. Parker

Since the introduction of electricity into the mines of the United States , the hazards incident to the industry have increased materially in both coal and metal mines . For economic reasons the tendency at present , particularly in coal mining , is decidedly toward the adoption of electrical mine machinery , including alternating current machinery , on a more extensive scale than ever before . Obviously, the growing use of such equipment will result in an ever -increasing number of underground transformer stations . The principal electrical hazards in mines are threefold ; fire , explosion, and contact . Of these , fire is the greatest hazard involved in the use of electricity underground , and several fires have originated in underground transformer and motor generator set stations . The fire hazard due to improperly installed and poorly maintained underground transformer stations is an ever-present one , and failure to take the necessariman remedial action is likely to result , sooner or later, in the destruction of life and property . Upon suggesting the necessary corrective measures with respect to such installations , one is often confronted with the statement to the effect that even though this particular hazard has existed over a period of years , there have been no unfavorable results therefrom thus far . Frequently , the desirability for action is not apparent to the mine management until it is too late . Because a mine has a record free from fires , explosions , etc. , over a number of years of operation during which these hazards existed , such good fortune should not be taken as a guarantee that this or any other mine is immune from these common dangers . When the elements of an existing hazard are properly balanced or in the right proportion, the unfortunate combination must of necessity culminate in misfortune of one kind or another. The fire hazard due to underground transformer installations can be very definitely minimized by proper installation and maintenance . In coal mines the transformer banks , connected to 2,300 and occasionally to 4,400 volt circuits , are often found located in open- ended crosscuts , mounted on concrete or timber foundations , and in nonfireproof surroundings .

Jul 1, 1930

By W. H. Forbes

The prevention of accidents from falls of roof and coal requires a considerable amount of personal judgment , for conditions are different even in adjoining working places in the same mine , and conditions may change from hour to hour even in the same working place as the coal is shot down and loaded . Experience has shown that many men can not or do not exercise enough care to protect themselves from injuries ; moreover , where the foremen have been made directly responsible for the safety of the men under them , accidents from falls of roof and coal have , in many instances , been reduced as much as 50 per cent . There is now no question that careful , constant , and intensive supervision is essential in preventing acci- { dents and more especially accidents of this class . Falls of roof and of coal account for approximately 50 per cent of all coal mine accidents and annually result in the death of approximately 1,000 men and cause lost - time injury to approximately 50,000 men . These and other accidents are recurring with little or no diminution , usually not because of the lack of knowledge of safe and dangerous practices , or of the technique of safety , but largely because of the lukewarm interest of major executives in safety or the failure of mine officials to formulate and to enforce common - sense rules and regulations . When failure is the outcome of a sincere attempt of the managing officials to teach safety to the miner , the fault may usually be attributed to misguided effort . Various solutions for the problem of eliminating accidents from falls of roof or coal have been suggested , some of which are : Standard system of timbering for the specified mining districts ; departure from the room-and - pillar system to a more concentrated system of mining ; more intensive supervision - that is , 1 section foreman for every 25 loaders instead of 1 section foreman for 75 , 80 , or even more loaders the practice in most mining districts . - However , investigations conducted by the writer at numerous mines operated by a number of mining companies in several districts show that employees and officials alike are inclined to work under loose and unsupported roof , relying solely on the " drummy " sound and on their judgment and experience as to whether the roof will stay in place for one hour or for several hours . With but few exceptions , men who had been injured by falls of roof or ccal or were found working under loose and unsupported roof , admitted that they knew of the possibly unsafe condition , but it was their opinion that the roof or coal was not loose enough to fall for some time .

May 1, 1931

By G. S. Rice, H. P. Greenwald

"Experience and experiment have goth shown that a cloud of coal-dust in air can be inflamed and an explosion developed only when a certain minimum concentration of the dust in air has been equaled or exceeded. Those who have had experience in the handling of coal know that dust is frequently present in the air and may be of sufficient density to obscure an ordinary electric light at a distance of 40 or 50 feet; yet flames may be, and times without number have been, introduced into such clouds, when no additional coal-dust has been stirred up, with no effect other than the burning of the dust particles which actually enter flame. Evidently the density of the dust cloud is insufficient to give self-supporting combustion.The minimum amount of dust in air required to give a spreading flame will vary with a number of factors such as the composition of the dust and its size. This amount in a unit space may be considered analogous to the lower limit of inflammability of fire damp (methane) in air, although the variation in limit of explosibility of gas is small even when conditions of the experiment are altered. In large-scale determinations of the lower limit of inflammability of coal-dust there is no certain method by which a sample of the dust cloud can be snatched and its density determined. It is necessary to produce the best possible dust cloud from a known weight of dust, in a known volume and assume - probably with considerable error - that the dust cloud is reasonably uniform. The dust cloud must be formed and the source of ignition applied to it simultaneously; this is generally accomplished by the use of blow-out shots of black blasting powder, dynamite, or similar explosive so prepared as to blow out like a cannon shot, or by a gas explosion. The more violence attending the source of ignition, the greater is the probability that all the dust is raised in a uniform cloud; and the greater the length or intensity of the flame, the greater are the chances of ignition. As a result one may obtain a variation in apparent minimum density with different sources of ignition. This difference is more apparent than real and must remain until devices for instantaneous sampling of dust clouds during explosions are perfected."

Aug 1, 1931

By O. P. Hood

The smoke problem means different things in different places . In the neighborhood of industrial plants , especially smelting plants and cement plants , the term " smoke " is applied to material discharged from these plants , consisting of a mixture of solid particles ( dust ) , fume which has condensed from vapors , and gases of various kinds that are produced in the operations . In the ordinary use of the word , however , " smoke" refers to the visible material which escapes from the burning of coal . White smoke usually owes its color to small drops of water which have condensed from the water vapor that it formed in the burning of coal . When smoke is black, the color is due to unconsumed particles of carbon and usually when the smoke problem is spoken of , it is this black smoke produced in the burning of coal that is referred to , Many inquiries in regard to smoke are addressed to the Bureau of Mines , and the following brief summary has been prepared as covering the usual questions . For references to the smoke problem in England , I am indebted to a recent interesting paper on this topic by David Brownlie .

Feb 1, 1922

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 H. H. Stoek

It would permit coal mines to operate continuously instead of intermittently . Intermittent operation increases the cost per ton for mining , and makes the yearly return to labor low . These conditions contribute to serious instability and unrest in one of the fundamental industries of the country and this can be changed only by coal buyers doing their part to insure steady work . The railroads are now required to transport the maximum amount of coal during the winter months when traffic is most interfered with by bad weather and when the maximum amount of coal is used by the railroads to handle other coal . The railroads now use nearly 30 per cent of the total output of coal . About one- third of their freight traffic is hauling coal , so that economy of fuel used by the railroads will produce a considerable gross saving .

Apr 1, 1920

By Harold L. Gibbs

The purpose of this paper is to encourage petrographers to prepare thin sections, as the demand for microscopic examination of rocks, ores, and metallurgical products is becoming more general in .the mining metallurgical-fields. This paper has been written with the knowledge that the successful thin-section methods and the several new techniques herein described will be helpful to all engaged in this field of work. Detailed instructions for making thin sections by methods developed at the Salt Lake-City laboratory of the Bureau of' Mines are given in this paper. Several new techniques are described for making thin sections of loose grains and fine sands and for making good thin sections of highly altered and friable rocks. The methods described insure superior bonding of the rock to the glass slide, thus virtually eliminating any failures due to parting of the section from the glass slide, and permit fast mounting, grinding, and finishing, thereby materially lessening the time required to prepare thin sections.

Jan 1, 1950

By John W. Frey

This paper presents one of a series of digests of foreign mining legis- lation and court decisions, which is being prepared in advance of a general re- port relative to the rights of American citizens to explore for minerals and to own and operate mines in various foreign countries. This interpretation of the laws governing the Portuguese overseas possessions, prepared from the best avail- able information in Washington, has been slightly amplified in accordance with suggestions transmitted through the courtesy of the Department of State by Fred Morris Dearing, American Minister at Lisbon.

Nov 1, 1929

By R. V. Ramani, K. V. K. Prasad

"This paper was the subject of a cross-disciplinary presentation under the chairmanship of Dr A.M. EdwardsManagers need quality information for effective decision making. This demand, at the present time, is being fulfilled by the increased use of computers via information systems, decision support systems and management information systems. The idea of incorporating intelligence into computers to aid decision-makers has been evolving for over two decades. In recent years, significant progress is reported on applications to business and sciences. In engineering functions, the Artificial Intelligence approach that seems to have great potential is the application of Knowledge Based Systems.The primary objective of this paper is to identify domains in mining engineering where application of knowledge based systems could be beneficial. Incorporation of the expertise required during the analysis and interpretation stages of an engineering design problem through knowledge based systems is recognized as an area of significant benefit. To this end, the components of knowledge based systems for mine ventilation and strata control design are described. The potential applications and limitations of knowledge based systems are outlined. IntroductionCorrect decisions are the key to success in any enterprise. Scope of decisions varies with the echelons of management hierarchy. The decisions of top management are strategic, relating to the long-term future of the organization. In a mineral organization, these deal with such issues as the acquisition of a new mineral property or the diversification of the business to exploit additional markets. At the operational level, a manager is concerned with decisions pertaining to day-to- day eventualities related to production activities and other short-term needs. In either case, the prerequisite is the timely availability and use of information. The difficulty involved in decision-making depends on the situational aspect. In. many cases, the decisions to be made under given conditions are fairly straight-forward and standard. This may be due to experience gained from decision-making in similar situations in the past. In fact, many decisions in operations management are either repetitive or routine."

Jan 1, 1989

By Frank E. Chase, John Rusnak, David Newman

During the past quarter century, coal mine geologists have evolved from providing a qualitative description of drill core and coal reserves into quantitative geotechnical specialists who bridge the gap between geology and engineering. In the late 1970’s and early 1980’s, hazard prediction mapping was in its infancy. At best, hazard maps identified rudimentary structures and conditions such as stream valley locations, sandstone/shale transition zones, and lineaments. A “technical disconnect” had existed between geologists and mining engineers as each profession operated largely independent of each other. Engineers did not readily integrate geology and geologic conditions, with the exception of coal thickness, into mine planning. Geologists were relied upon for reserve estimates and did not participate in mine planning or design. The employment and market slump of the 1980’s and 1990’s combined with mining more challenging reserves mandated that this gap be bridged and forced geologists to learn to speak more “numerically” to engineers so they could be understood. The purpose of this paper is to describe the procedures and thought processes used by coal mine geologists when determining various mineability and reserve extraction feasibility issues. The paper will also address underground geologic hazard mapping and prediction techniques. To achieve these objectives, the opinions and experiences of leading coal mine geologists, geotechnical and strata control specialists across the United States were solicited.

By R. V. Ramani

"In Part 1 of this paper, published in the August 1995 issue of Natural Resources Forum, a review of several mining disasters around the world established the complex nature of their causation and their catastrophic effects. The involvement of human beings, either through acts of commission or omission, was highlighted. In Part 2, a discussion of the various approaches to disaster control, mostly as practised in the USA, is presented. A systems approach to disaster prevention incorporating elements of hazard identification, mine design, emergency response and post-emergency audit is presented.In the USA the role of government in the affairs of its citizens is continually growing. This role is intended to ensure an unimpeded pursuit of happiness and prosperity by the population and to curtail actions which are restrictive or harmful to the citizenry. The passage of a legislation is an indication that it has been decided through the established process that the activities covered by the legislation should receive appropriate consideration. The enactment of the Coal Mine Health and Safety Act of 1969 (The 1969 Coal Act), the Mine Safety and Health Amendment Act of 1977 (The 1977 Mine Act) and the Surface Mining Control and Reclamation Act of 1977 (The 1977 Surface Mining Act), was specifically intended to further the role of government in the health, safety and environmental affairs of the mineral industry.Currently, the federal government's responsibilities for mine safety and health are divided among three agencies: the Mine Safety and Health Administration (MSHA) in the US Department of Labor, the Bureau of Mines (USBM) in the US Department of the Interior and the National Institute for Occupational Safety and Health (NIOSH) in the Department of Health and Human Services (National Research Council, 1981). MSHA is responsible for issuing and enforcing mine safety and health regulations, for training miners and for responding to mine emergencies. The Bureau of Mines is responsible for conducting research on mine safety and on the technological means for reducing health and safety hazards in mines. NIOSH conducts research relating to miner health, and together with MSHA, tests and certifies devices used to detect hazardous materials in mines and protective equipment used by miners. NIOSH also plays a public health role in that its activities in mining include health hazard evalua¬tions, general mining surveillance as mandated by law and medical surveillance including coal miner X-ray and autopsy programmes. MSHA shares with the Bureau of Mines the responsibility for integrating R&D results into operational practice. MSHA implements R&D results either by incorporating them into its own operations or by rule making that requires new practices or equipment to be adopted by the mining industry. In many instances, the Bureau's R&D results have been adopted by the mining industry without rule making."

Dec 1, 1996

By W. W. Weller

Low-temperature heat capacity measurements were conducted, and entropies at 298.15° K were evaluated for sodium monomolybdate (Na2Mo04), magnesium monomolybdate (MgMo04), and calcium monomolybdate (CaMo04). The 298.15° K entropy values were sodium monomolybdate, 38.1±0.3 cal/deg mole, magnesium monomolybdate, 28.4±0.2 cal/deg mole, and calcium monomolybdate, 29.3±0.2 cal/deg mole.

Jan 1, 1963