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By F. E. Cash

"In the interest of accident prevention it is felt that a report of the measures taken during the past four years toward the reduction of fatal accidents in Alabama, especially in preventing falls of roof and coal, will be of interest throughout the mining districts.In order to determine the primary factors in the reduction of fatal accidents from falls of roof and coal, the operators, State Inspection Department, and the Alabama council of the Holmes Safety Association were asked: ""What has your organization done to help in the reduction of accidents from fails of roof and coal?"" The responses to this question have made this report possible.To bring out briefly the reduction in fatal accidents from falls of roof and coal as well as from all causes, the following three tables have been prepared.These statistics have been compiled from the records of the State Inspection Department.In the order mentioned, it is felt that credit for the reduction in fatal accidents from falls of roof and coal should be given to the individual operating companies, the State Inspection Department, the Alabama council and chapters of the Holmes Safety Association, and the Alabama Mining Institute. The individual operating companies naturally head the list in that they are directly concerned from a humanitarian as well as a financial point of view. The State Inspection Department through frequent and thorough inspections and by providing necessary statistics is largely responsible for the reduction. The Alabama council and its affiliated chapters of the Joseph A. Holmes Safety Association through its publicity and education reaches a large number of employees throughout the mining district. The Alabama Mining Institute defrays the council expenses and thus makes possible much of this service to the Alabama mining industry.In 1925 there were 49 fatalities, equivalent to 115,169 man days per fatality, from falls of roof and coal, which was by no means a good record; in 1926 the number and frequency of accidents were reduced to 42 fatalities and 149,096 man days per fatality. When in 1927 the fatalities from this cause mounted to 61 and the man days per fatality were reduced to 89,903, it was quickly realized that more concentrated efforts must be exerted to reduce such accidents.As early as August, 1927, at which time the fatalities from falls had reached a total of 31, the following letter from the Chief Mine Inspector was written to each operating company in the State and was the initiation of a very strenuous campaign by all parties concerned towards the reduction of accidents from falls of roof and coal."

Nov 1, 1929

By R. D. Currie

"A million tons of coal mined in the Pennsylvania anthracite region without a fatality is a feat of which to be proud and one that deserves the commendation of the entire mining industry. The average production per fatality in this region for 1933 was 206,823 tons, an exceptional record showing the results of an intensive drive made by the Pennsylvania Department of Mines and the anthracite operators and-workers to curtail the high accident rates heretofore prevailing in the region.This paper gives information about a mine with a record five times better than the average which should prove to the industry that mine accidents can be reduced through the proper safety organization and effort. The Pine Hill Coal Co., managed by Weston Dodson & Co., Inc., and located at Minersville, Schuylkill County, Pa., has made such a record at its Oak all colliery by studying its accident experience, realizing the facts, and pursuing a definite safety policy with a view to bettering its accident occurrence.As a direct result of its safety policy this colliery has produced 1,044,000 tons of anthracite without a fatality; within 3 years it has reduced its total accidents from 645 to 105 per year, its compensable accidents from 204 to 45 per year, and its lost-time accidents from 335- to 67 per year. In addition, it has set up a smoothly functioning safety organization that will go fax in aiding in the continuance of this great work of mining anthracite at a lower .cost in human suffering.This circular describes the accident-prevention methods perfected and the results obtained by this colliery in the belief that similar methods will produce essentially similar results at any other colliery where they may be adopted.The writer acknowledges his indebtedness to the officials of the company who furnished him with the details of the safety organization and the data from which this report was prepared. He especially desires to thank Messrs. Stockett, general manager, Wells, general superintendent, Morgan, safety engineer, and Kistler,- statistical department, for their hind assistance.The mine is opened by shafts, slopes, and drifts, a characteristic of minas in the Southern anthracite field. Thirteen different beds of coal are being mined. The thickness of the beds ranges from 3.5 to 16 feet and the pitch from 0 to 900. The roof and floor exhibit the entire range of conditions found in anthracite mines. Table 1 describes the coal seams being worked."

Aug 1, 1934

By E. P. Youngman

The mining laws of Russia (Collection of Laws, vol. 7, 1912) are still in force in Latvia. The Free State of Latvia (declared independent on November 8, 1918) is composed chiefly of the Baltic Provinces of the former Russian Empire, which are ethnographically Lettish: The Province of Courland, four districts of the Province of Livonia, and three districts of the Province of Vitebsk. Since the establishment of its independence, Latvia has not felt the need of a special mining law, inasmuch as mining so far has not been found profitable in that country. A supplement to this paper, entitled "Mineral Resources," is a brief summary of the minerals found and utilized in latvia. RIGHTS OF FOREIGNERS A foreign individual is permitted to explore for minerals and to own and operate mines in Latvia on equal terms with Latvians. A foreign corporation is required to establish a branch in Latvia, which shall be subject to the corporation laws of the country. A certain number of the partners or incorporators must be citizens of Latvia.

Nov 1, 1931

By Michael A. Evanto, George J. Karabin

The Mine Safety and Health Administration, Pittsburgh Safety and Health Technology Center, Roof Control Division, is routinely involved in the evaluation of ground conditions in underground coal mines. Assessing the stability of mined areas and the compatibility of mining plans with existing conditions is essential to ensuring a safe working environment for mine workers at a given site. Since 1985, the Roof Control Division has successfully used the boundary-element method of numerical modeling to aid in the resolution of complex ground control problems. This paper presents an overview of the modeling methodology and details of techniques currently used to generate coal seam, rock mass, and gob backfill input data. A summary of coal and rock properties used in numerous successful evaluations throughout the United States is included, and a set of deterioration indices that can aid in the quantification of in-mine ground conditions and verification of model accuracy is introduced. Finally, a case study is detailed that typifies the complexity of mining situations analyzed and illustrates various techniques that can be used to evaluate prospective design alternatives.

Jan 5, 1999

By J. W. Thompson

OWNERSHIP OF ORE-CONSTRUCTION OF CONTRACT. A contract between the Republic Mines Corporation and the Quilp Gold Mining Co. provided that upon forfeiture of its rights under a contract the Republic Mines Corporation was required to give a good and sufficient deed conveying to the Quilp Gold Mining Co. all ore bodies of every description lying east of the west line of the Quilp Mining Co. claim extended downward vertically and lying south of the north end line of the Quilp claim extended downward vertically and which may apex within the lines of the Surprise, an adjoining mining claim. It must be presumed that the contracting parties under such circumstances had in view their statutory rights as provided by the mining statutes of the United States, and that both were familiar with the provisions as to extra- lateral rights granted by the statute to locators of mining claims. This contract means to include all ore bodies of every description lying east (or easterly) of the west (or westerly) line of the Quilp claim extended downward vertically and south (or southerly) of the north end line of the Quilp claim extended downward vertically within the Quilp claim excepting the part that was overlapped by the Surprise claim, owned by the Republic Mines Corporation. Quilp Gold Min. Co. v. Republic Mines Corp. (Washington), 165 Pacific 57, p. 61. PURCHASE OF GAS-REFUSAL TO DELIVER SALE TO OTHERS. A gas company that had entered into a contract to purchase a quantity of natural gas refused to receive and accept the gas that was tendered on the ground that it did not conform to the requirements of the contract; subsequently the company refused to sign a writing by which it was asked to consent to the sale of such gas to other persons. But the refusal of the purchasing company to sign such a writing giving its consent or its refusal to consent to such sale did. not affect the rights of the seller to dispose of the gas elsewhere and to other persons. OWNERSHIP OF MINERALS IN HIGHWAY. All mineral deposits within the limits of a highway belong to the owner of the fee and he is entitled to remove them so long as he does not interfere with the public use of the highway. City of Scranton v. Scranton Coal Co. (Pennsylvania), 100 Atlantic 813, p. 819. SALE AND CONVEYANCE. SALE AND CONVEYANCE EXCEPTION AND RESERVATION. The owner of an undivided interest in oil and gas lands conveyed the same to certain named grantees by deed containing a clause excepting and reserving all the oil and gas produced from the undi- vided interest in the land described. The language is not apt for the creation of either an exception or a reservation, but is rather that of a layman unfamiliar with legal distinctions. Strictly and literally construed, it affords a basis for a contention that that which was excepted and reserved was not realty in any form or anything inci- dent thereto, but personalty produced from the land. Immediately following the description of the tract, the grantor excepted and reserved something from the land described. What he excepted and reserved, he excepted and reserved then, and it was from his interest in the land. The clause expressed according to the evident intention of the grantor would read: "Excepting and reserving from the above all oil or gas which may hereafter be produced therefrom." No other construction can reasonably be placed upon the language used. The carving out of a separate estate in the oil and gas in land is a common occurrence in oil and gas producing fields. Mandle v. Gharing (Pennsylvania), 100 Atlantic 535, p. 536. RESERVATION CONSTRUED AS AN EXCEPTION. Where apt words of reservation are used in a deed they will be construed as an exception where this is the evident intention of the parties to the instrument. Although an exception and a reservation differ in legal effect, yet in their creation there is no magic in words, and if the meaning is clear either expression will operate for the purpose designed. The technical distinction between an exception and a reservation is frequently disregarded in the ordinary use of the word, and whether the language used creates an exception or a reservation must be determined from the intention of the parties ascertained from the entire instrument.

Jan 1, 1917

By David Hoadley, Kenneth R. Maser, Ashok B. Boghani, James E. Billar, D. Randolph Berry, Mackenzie Burnett, Robert H. Trent

A. 3 Program Description The computer program developed to simulate events in the case of fire in the mine is described in this section The description is divided into three parts. 1. Program Capabilities This part summarizes what inputs can be changed, what outputs can be obtained and demonstrates program flexibility through suggested uses.

Jan 1, 1976

By Robert P. Vinson, John C. LaScola, Fred N. Kissell, Edward D. Thimon

The face ventilation measurement method developed by the Bureau of Mines involves releasing a small volume of tracer gas (SF6) on the off-curtain side of the working face at the start of the mining cycle. At the same time, gas bottle samples are taken in the immediate return airway. The gas samples are analyzed, and a curve is drawn of SF6 concentration versus time. From this curve, the percentage of gas removed per time is calculated. A curve showing a high percentage of the tracer gas removed in a short period would represent a well-ventilated face. The face ventilation measurement method was tested in a full-scale mine entry model. Subsequently it was used underground to evaluate the spray-fan ventilation system and in an MSHA test facility to test machine-mounted scrubbers. The method was shown to be a simple and effective way of evaluating face ventilation systems.

Jan 1, 1980

By C. E. Jordan

The Bureau of Mines conducted tests on seven samples of Florida phosphate operations.slimes to develop a method to recover phosphate presently being discarded because of its small grain size. A system of hydrocyclones and hydroseparators was used to recover up to 96 pct of the plus 400-mesh material from the slimes. This plus 400-mesh material was subjected to fatty acid flotation, and concentrates containing up to 33.4 pct P205 were produced. As much as 88 pct of the phosphate (P205) was recovered from the plus 400-mesh material, and up to 29.6 pct was recovered from the total slimes.

Jan 1, 1982

By Gerrit V. R. Goodman, Jeffrey M. Listak, John A. Organiscak

Data on dust control practices, geology, and occupational exposures were gathered for approximately eighty underground continuous mining units. Despite silica contents in excess of 5%, nearly forty units successfully maintained silica concentrations at or below 100 µg/rn3 on a majority of occupational dust samples while the remainder had difficulty maintaining this level. These two sample sets were termed group A operations and group B operations, respectively. Analyses of productivities, geologies, and dust control parameters revealed only minor differences between these two groups. Subsequent analyses of face ventilation design showed considerable differences in silica exposure and silica content between group A and group B at the continuous mining machine and roof bolter operator occupations. These differences were minimal when using exhaust curtain ventilation with a dust scrubber', This face ventilation system may benefit operations having difficulty controlling silica dust exposure and silica dust content. Finally, the collected data showed that occupational samples from group B operations possessed generally higher silica exposures and silica content than similar samples from group A. The single head roof bolter (helper) possessed among the highest silica exposures and silica contents in both groups.

By Dennis Dolinar, Russell Frith, David Oyler, Christopher Mark

Unusual circumstances may require that a longwall retreat into or through a previously driven room. The operation can be completed successfully, but there have been a number of spectacular failures which exposed miners to serious roof fall hazards. To help determine what factors contribute to such failures. the National Institute for Occupational Safety and Health (NIOSH) compiled a comprehensive international database of 130 case histories. The cases include five failures where major rock falls occurred in front of the shields, and six even more serious failures involving major overburden weighting. This suggests two room failure mechanisms The first is a roof fall type failure caused by loading of the immediate roof at the face as the fender narrows. The second is a weighting type failure caused by the inability of the roof to bridge the recovery room and face area, and affecting rock well above the immediate roof The data indicate that the roof fall type of failure is less likely when intensive roof reinforcement (bolts, cables, and trusses) is employed together with higher-capacity shields The overburden weighting failures, in contrast, occurred when the roof was weak and little standing support was used

By E. J. Babcock

The existence of vast deposits of lignite in the West Central and Western States is well known, although the extent and importance of the deposits have not been appreciated, nor has there been an adequate economic utilization of the deposits. The work of the Bureau of Mines, the United States Geological Survey, and the State geological surveys is disclosing an increasingly large area, underlaid with this kind of coal. Among the States having the largest workable deposits may be mentioned North Dakota, Montana, Wyoming, Colorado, and Texas, and in several other Western States lignite occurs in smaller areas. In North Dakota alone it is estimated that the deposits cover approximately 32,000 square miles, many of them being 10 to 15 feet thick and capable of producing in all several hundred billions of tons of lignite. When one stops to consider what these figures mean as to the immensity of these deposits in the West, it is not strange that people are seeking to ascertain better means for deriving larger benefits from the proper utilization of those great deposits. Consequently, any proposed methods of utilization that are promising are well worthy of careful consideration.

Jan 1, 1915

By L. W. Scott, T. H. Dubaniewicz, F. T. Duda, P. G. Kovalchik

Recent research conducted by NIOSH, Pittsburgh Research Laboratory showed that electrical current levels permitted under parent regulations may not limit cable temperatures to less than 90 °C in reeled trailing cables. Reeled cables, tightly wrapped with many turns, ell carrying current in an enclosed space, can become overheated due to poor heat transfer. This overheating can cause the cable insulation to soften and become easily damaged. The damaged insulation reduces the life of the cable and can lead to shock, electrocution, and mine foes. This paper describes a method of measuring the conductor temperature of untie trailing cables during no anal operation. The temperature is measured using a 50/175 micrometer Graded Index Multimode Optical Fiber located in the center of the metallic conductors. Distributed temperature measurements arc made using an Optical Time Domain Reflectometer (OTDR). This system is capable of measuring temperature with an accuracy of plus or minus one degree centigrade over a length of 4 km at 1-m intervals. With this unique way of measuring temperature, tests can be conducted simulating actual mine conditions and provide important data to allow MSHA's Approval and Certification Center to develop approval criteria for cyclically rated reeled machines.

By John A. Johnson

"INTRODUCTION The use of wet drilling with adequate ventilation has largely controlled production of dust in drilling rock; however, in some operations, such as shaft sinking and modern tunnel driving, when each of a number of drills is operating in a small cross-sectional area, it is at times difficult to ventilate well enough to keep the dust concentration within desired limits.Some chemical compounds, known as wetting agents, when added to water in small quantities reduce the interfacial tension and make it possible for the solution to wet dust particles more effectively than water alone.This report presents results of tests on the effectiveness of two wetting solutions in reducing the amount of dust produced by wet drilling in basalt.ACKNOWLEDGMENTSThe tests were conducted at the Bureau's Mount Weather Testing Adit, Mount Weathe, Va. The author acknowledges the assistance and cooperation of Wing G. Agnew, superintendent; Marvin M. Reveille, mining-ngineering aide; and the rest of the crew at Mount Weather in conducting the tests. C. W. Owings, mining engineer, Safety Division, assisted in conducting some of the first tests and gave valuable advice and guidance throughout the work and in preparing this report."

Jan 1, 1943

Coal is found in the northeast comer of Georgia, in Dade, Chattooga, Walker, and Floyd Counties. Five seams, which underlie all of Lookout, Sand, and Pigeon Mountains, have produced most of the coal mined in the state. Representative analyses of Georgia coals show that they are typically low sulfur (less than one to one percent), low-to-medium volatile, bituminous deposits. Although there is no active mining in the state, reclamation continues on several permitted areas. In 1983 the State of Georgia relinquished primacy to the Office of Surface Mining. Since that time permits have been issued and mining completed. All the sites are presently in the process of bond release.

Jan 1, 1992

By R. Larry Grayson

Barrett EA, Kowalski KM [1995]. Effective hazard recognition training using a latent-image, three-dimensional slide simulation exercise. Pittsburgh, PA: U.S. Department of the Interior, Bureau of Mines, RI 9527. NTIS stock number: PB95-170379. Beus MJ, Orr TJ [1995]. Computer modeling and analysis of the Greens Creek Mine, Admiralty Island, AK. Spokane, WA: U.S. Department of the Interior, Bureau of Mines, RI9530. NTIS stock number: PB95-176418. [ ]

By W. P. Yant

Public interest in atmospheric pollution by automobile exhaust gas and in the ventilation of vehicular tunnels makes it desirable to ascertain whether the use of modern automobile fuels is tending to change the amount and composition of the products of combustion. The Bureau of Mines, in cooperation with the Ethyl Gasoline corporation4, has completed a series of testis to determine whether any significant difference exists in the carbon monoxide content of the exhaust gas produced by an internal-combustion engine when its fuel is changed from straight gasoline to the same gasoline containing Ethyl fluid whose active ingredient is tetraethyl lead. In the tests data was sought relative to the composition and mount of the gas produced by ordinary comparatively low-compression motors as well as by higher-compression motors in which distinct detonation occurred with straight gasoline, but which operated without detonation when using the same gasoline containing tetraethyl lead.

Jan 1, 1929

By R. J. Matetic, D. Elsworth

The objective of this U.S. Bureau of Mines hydrologic-subsidence investigation was to evaluate the effects of longwall mining on the local ground water regime through field monitoring and numerical modeling. Field data were obtained from multiple-position borehole extensometers (MPBX's) that were used to measure subsurface displacements. Survey monuments were installed to measure mining-induced surface deformations. Numerous drawdown and recovery tests were performed to characterize hydrologic properties of the overburden strata. Coreholes were drilled above the study area to determine lithologic and strength characteristics of the overburden strata using the rock samples collected. Electronic recorders were installed on all monitoring wells to continuously monitor ground water levels in coordination with mining of the longwall panels. A combined finite element model of the deformation of overlying strata, and it's influence on ground water flow was used to define the change in local and regional water budgets. The predicted effects of the postmining ground water system determined by the model correlated well with field data collected from the field site. Without an infiltration rate added to the model, a static decrease of 3.0 m (10 ft) in water level would occur due to mining of both longwall panels and if an infiltration rate was inputted in the model, no predicted long-term effects would occur to the ground water system.

Jan 1, 1995

By R. V. Ramani, V. T. Burgos, J. A. McClay

Cost Systems Cost systems are organized methods of collecting, allocating, and accumulating resource utility expressed in terms of money. There are two major spheres of cost accumulation: financial accounting and cost accounting. Financial accounting deals primarily with historical costs and provides a means of measuring and recording cost events which have al¬ready taken place. While there are no legal requirements to control the methods of recording and reporting cost data in the United States, the procedures in use are guided by professional organizations such as the American Institute of Certified Public Accountants. The final pro¬ducts of financial accounting practices are the income statement and balance sheet which describe the financial status of the organization under study. Cost or managerial accounting is an expansion of financial ac¬counting procedures, providing more detailed cost breakdowns on present operations with one objective being the projection of present costs into the future. The projection process tends to limit the accuracy of the information; however, to management and project justification per¬sonnel, data on future operations tends to be of greater value. The basic principle behind cost accounting is the cost cycle. As products are developed from raw materials, the value of the work-in¬process increases due to the cost input of the various fabricating ele¬ments. Thus, from the basic input elements of facilities, labor, and raw materials, costs are added to each unit of production as a function of the work performed on that unit.

Jan 1, 1975

By D. Harrington

Recently the attention of the U. S. Bureau of Mines has in a number of instances been called to the firing of shots of permissible explosives in coal mines with delay-action detonators. In one bituminous coal mine they were used to bring down the coal for conveyor loading; in another in blasting pillars, which were not undercut; in another in one of the two charges separated by stemming in deep drill holes where the coal was undercut and sheared and mechanically loaded; in another in shooting top coal; and in another in the shooting of coal faces electrically from the surface. Some of these mines were rated as gassy by the State Mining Department in the State concerned. In most instances the charging of holes was done while the working shift was in the mine, and in some the shots were blasted while the working shift was in the mine. In all of these cases the shots were dependent - that is, the efficacy of the succeeding shots was dependent - upon the firing of the preceding shot or shots. The first shot, or possibly two or three shots, was usually fired with a no-delay electric detonator or an instantaneous electric detonator.

Jan 1, 1929

By G. Nuñez, M. A. Pathak, A. A. Afshari, C. F. Stanley

"To help evaluate the vibration patterns of an excised lung, a method is developed to determine which parts of the surface of an excised lung are responding to acoustic excitation via the trachea. Holographic interferometry, a very' sensitive technique ·that can measure movements of a few microns, is used to detect the lung surface movements.The intact lung and heart are excised from Long· Evans male rats weighing 250 gm. A tube is inserted into the trachea and connected via a funnel to a 3 inch cone speaker. The assembly is positioned in the holographic unit and excited at frequencies up to 10,000 Hz. The holographic unit contains an acousto-optic shutter used with a 0.5 watt Argon laser.The resulting reconstructed holograms contain interference fringes that are indicated of lung surface vibration.INTRODUCTIONA 1986 report by the U.S. National Committee on Biomechanics [1] describes diseases of the lung as a major national health problem. One of the recommendations of the report is for continued study of the mechanical properties of lung tissue. As an example, the report cites at least three areas that would benefit from a better understanding of the vibratory patterns or the lung."

Jan 1, 1989