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By Eric Brandner

Expansive soil formations can be found throughout the United States. When subjected to wetting, many of these formations have the potential to swell and exert large uplift forces which can significantly damage lightly-loaded structures. Designing an economical foundation that can resist uplift forces is critical to prevent damage to these structures. The current solutions to control uplift due to swelling soils, such as over-excavation and replacement of the expansive material, or drilled shafts, can be costly and problematic. Piles made from recycled polymer materials may provide a solution. Due to a lower coefficient of friction along the interface than piles made from traditional materials, solid recycled plastic piles can allow expansive soils to move nearly independently from the pile when wetted. This results in a much smaller magnitude of uplift force being transferred to the structure which minimizes the risk of significant structural damage. This paper presents the preliminary results of research conducted on the use of recycled plastic piles in an expansive shale environment. The preliminary phase of the project involved the installation of six 13 in. (330 mm) diameter recycled plastic piles at a test site on the South Dakota School of Mines and Technology campus. The piles varied in length from 15 ft. to 25 ft. (4.6m to 7.6 m). Two of the piles were subjected to a full-scale compression load test in order to determine ultimate capacity, while the additional four piles are being subjected to long-term monitoring of uplift movement. A cast-in-place concrete pile, with a diameter of 6 in. (152 mm) and length of 15 ft. (4.6 m), was also installed at the test site for monitoring. The preliminary results indicate that the use of solid recycled plastic piles is a viable alternative for support of lightly-loaded structures in expansive soil environments.

Jan 1, 2009

By James W. Griffith, Sarah A. Riling

Bituminous coal dust was repeatedly placed into one lung lobe of anesthetized Macaca nemestrina monkeys using a flexible fiberoptic bronchoscope. Radiographs taken at 15 day intervals showed a focal radiographic density after 90 days time when a total of 1 gram of dust had been instilled. The radiographic density progressed slightly in size until 12 months by which time 3 grams of dust had been instilled and the animals were euthanized. At necropsy, the only significant gross lesion detected was the focal black pulmonary lesion located at the dust instillation site. Histologically, the lesion was composed of coal dust laden macrophages located primarily within interstitial tissue and interspersed with a slight amount of reticulum and connective tissue fibers. The distribution of coal dust was limited to the instillation site in the right caudal lung lobe based on radiographic, gross and histologic examination. Bronchoalveolar lavage of both right and left caudal lung lobes was performed 8 times during the 12 month long experiments without significant complications. More macrophages were found in lavage fluid from the right lung than the left, and most macrophages from right lung contained coal dust particles. Based upon a limited physical examination and complete blood count at 15 day intervals the animals remained normal during the experiment. We conclude that the primate lung's response to focal experimental bituminous coal dust resulted in a marked focal increase in pulmonary alveolar macrophages, which can be recovered regularly in high numbers by bronchoalveolar lavage. The model described has significant potential for investigating the pathogenesis of various respirable dust-induced pneumoconioses, for evaluation of new therapeutic approaches, and for refining experimental and clinical diagnostic applications of bronchoalveolar lavage. Key words: Coal Workers Pneumoconiosis, Disease model; Primate, Lung Lavage Fluids

Jan 1, 1991

By John C. Loretta

INTRODUCTION Organizations that regularly use project management services will almost certainly have their own views on the preferred systems and procedures. This chapter, therefore, describes Project Management for the personnel of groups not familiar on a regular basis with project management and deals with the basic questions that these groups can be expected to ask, such as: - What is project management? - Why is it needed? Project Management is the planning, implementation and monitoring of the Engineering, Procurement and Construction activities that are necessary to complete the project in the most economic manner. In the case of a crushing and grinding plant, completing the project would mean bringing it into full operat ion. Engineering is the design work for the purpose of producing drawings and technical specifications for Construction together with technical specifications and quantities for Procurement. Procurement is the arranging of con- tracts so that equipment, material and labour are brought as required to the construction site. Construction covers the on-site activities that bring together the components of Engineering and Procurement so as to arrive at a finished plant. Need & Cost Benefits Project Management systems are needed to allow progress and expenditures to be monitored so that any significant deviations from the plan can be identified and the appropriate corrective action taken. In this way, Project Management is able to give continual updated answers to the Owners broad questions. - What am I getting? - What will it cost? - When will it be ready? The need for Project Management is not always immediately apparent, a common belief being that the existence of the three components -Mining Company - Equipment Supplier - Construction Company - is sufficient to get the job done without a formal project management group. This trio

Jan 1, 1982

By P. M. Lin

The problem of abandoned mine land (AML) subsidence is getting more severe because abandoned mine lands which used to be located in the remote areas have been gradually developed into suburbs or even urban areas. Abandoned mine subsidence is also becoming more common than before because the time-dependent effect of exposed underground materials. These materials will deteriorate gradually and cause subsidence as time passes. Subsurface conditions of abandoned mines are seldom known to the public. Mine maps are not always available. If the mine mans are available, their accuracy are very - often questionable. In addition, the most common damages to surface structure and ground surface due to mine subsidence can also be created by other non-mining related geological hazards. These factors make the study of abandoned mine subsidence significantly complicated, tedious, and inconclusive. For instance, the cause, time, and amount of surface subsidence can be predicted with relative accuracy during active mining. However, it will be a considerable challenge to do so on abandoned mine subsidence. If abandoned mine subsidence can be predicted in advance, then the damages can be held to a minimum. However, this prediction technique is not yet well developed. Therefore, remedial measures require more attention. In order to have effective remedial measures, the real cause of the damage should be determined first. This paper describes the approach which was employed for the determination of abandoned mine subsidence. A site investigation was made first. According to the information obtained from the site investigation, a hypothesis was set up. Then the instrumentation was used to prove the hypothesis. By going through the procedures for several cases, a guideline which can be used by the inspectors to inspect abandoned mine subsidence will be established.

Jan 1, 1987

By A. Sampson-Forsythe, P. Morissette, A. R. Punkkinen, D. R. Chinnasane

"The performance of ground support systems under dynamic loading is typically assessed in a qualitative and subjective manner. As a result, it is difficult to develop an explicit knowledge on the mechanisms of action and interaction of support elements subjected to rockbursts. This paper examines rockbursts that have occurred at Creighton, Copper Cliff, and Coleman mines since 2000, 2004, and 2006, respectively. The mines are located in the Sudbury Basin, in Ontario, Canada. The majority of pertinent information was obtained through on-site field assessments, seismic system records, and numerical elastic stress modelling. Passive monitoring is used to link the evolution of the frequency and severity of rockbursts to the evolution of mining and support practice at the three mine sites. Based on the collected data, ground support elements that enhanced the capacity of support systems to withstand dynamic loads are identified. IntroductionThe selection of appropriate mining methods, extraction sequences, rock mass de-stressing techniques, and ground support systems is of great importance in mitigating the level of rockburst-related risk. In burst-prone conditions, the design of support systems should account for the anticipated dynamic load demand and the capacity of the available support options. Furthermore, an economical design should, implicitly or explicitly, take into consideration the consequences of a rockburst and its impact on worker safety and mine productivity. Stacey (2012) has argued that we have a limited understanding of the mechanisms of rock mass behaviour in seismic conditions. This is compounded by a ‘lack of understanding of the mechanisms of action and interaction of support elements under dynamic loads’ (Stacey, 2012). Consequently, the design of support systems required to manage dynamic loads is usually based on experience. The assessment of the dynamic performance of ground support systems is typically subjected to qualitative (and sometimes subjective) interpretations from ground control personnel."

Jan 1, 2017

By Craig R. Barrett, Jack L. Lytton, Oleg D. Sherby

The types of substructures developed during high-temperature creep of (110)[001]-oriented polycrys-talline Fe-3.1 pct Si were examined by electroetching of dislocation sites. Edge dislocations were observed to accumulate adjacent to grain boundaries and poly-gonize perpendicular to their glide planes to form a "Pile-up" of nearly parallel tilt boundaries. The dislocation density developed within the grains during steady-state creep was found to increase with increasing stress. The formation of periodically spaced groups of edge dislocations along grain boundaries was observed, and it was proposed that these formed to relive bending stresses at grain boundary shear .faults. Grain boundary serrations developed at these faults, and it was suggested that this was a result of localized grain boundary migration at the polygonized groups. THE authors have conducted a series of high-temperature creep tests on (110)[001]-oriented poly-crystalline Fe-3.1 pct Si sheet. The creep specimens were examined at various stages of creep by means of electrolytic etching of dislocation sites using the chrome-acetic acid solution developed by Morris.' Hibbard and Dunn2 have demonstrated that the etch pits produced with this technique correspond to single dislocations. It is the purpose of this paper to present and discuss the dislocation substructures which were formed during high-temperature creep at constant stress. EXPERIMENTAL PROCEDURES The polycrystalline Fe-3.1 pct Si sheet employed in this study contained a (110)[001] texture. This texture was quite strong, and the elastic properties of the sheet closely approached those of a single crystal of iron.3,4 A typical analysis in weight percent for this material is 3.1 Si, 0.1 Mn, 0.003 C,

Jan 1, 1965

By Marcia Harris, Richard Mainiero

The New York State Department of Transportation recently commenced highway widening and drainage improvement projects in Clarence and Amherst, NY. Drainage improvements including the installation of storm sewer lines required excavation to a depth of 2.5 m (8.2 ft). In September 2002, NYSDOT stopped further blasting when 800 ppm CO was detected in the basement of a house near the blasting site. At the insistence of NYSDOT, the general contractor developed a new blast plan with the assistance of an environmental consultant. The plan provided for the installation of multi-gas monitors in buildings of special concern and/or with basements and residential type CO monitors in all other buildings within 100m (330 ft) of the blast. The multi-gas monitors would be remotely monitored. The plan provided action levels which would ensure public safety. The blast design was also modified to allow for better venting of CO. Blasts were limited to 20 ft lengths. The overburden was to be removed from the rock and blasting mats put in place to prevent flyrock. Approximately twenty feet of trench adjacent to the blast was left open to allow ground movement and gas release. The use of CO monitors was effective to alert occupants of a building to the presence of CO. The most effective appeared to be the residential type CO alarms with digital readouts. They were simple and easy to use and allowed the public to participate in the process. False alarms were repeatedly received with the more sophisticated instrumentation. Residential type CO monitors are preferable to warn people near blast sites. More sophisticated instrumentation should be avoided unless personnel are experienced in its use. A general overview of the blasting and monitoring is presented and discussed. The use and effectiveness of residential type CO monitors and multi-gas monitors are discussed.

Jan 1, 2004

By Richard J. Mainiero, Marcia L. Harris

The New York State Department of Transportation recently commenced highway widening and drainage improvement projects in Clarence and Amherst, NY. Drainage improvements including the installation of storm sewer lines required excavation to a depth of 2.5 m (8.2 ft). In September 2002, NYSDOT stopped further blasting when 800 ppm CO was detected in the basement of a house near the blasting site. At the insistence of NYSDOT, the general contractor developed a new blast plan with the assistance of an environmental consultant. The plan provided for the installation of multi-gas monitors in buildings of special concern and/or with basements and residential type CO monitors in all other buildings within 100m (330 ft) of the blast. The multi-gas monitors would be remotely monitored. The plan provided action levels which would ensure public safety. The blast design was also modified to allow for better venting of CO. Blasts were limited to 20 ft lengths. The overburden was to be removed from the rock and blasting mats put in place to prevent flyrock. Approximately twenty feet of trench adjacent to the blast was left open to allow ground movement and gas release. The use of CO monitors was effective to alert occupants of a building to the presence of CO. The most effective appeared to be the residential type CO alarms with digital readouts. They were simple and easy to use and allowed the public to participate in the process. False alarms were repeatedly received with the more sophisticated instrumentation. Residential type CO monitors are preferable to warn people near blast sites. More sophisticated instrumentation should be avoided unless personnel are experienced in its use. A general overview of the blasting and monitoring is presented and discussed. The use and effectiveness of residential type CO monitors and multi-gas monitors are discussed.

By Bruce H. Gardner

This paper describes the application procedure of the Stress Control mine design method. This procedure has evolved over the past 20 years of the practice of this Method in trona, potash, salt, and, most recently, in coal mining. The Stress Control Method of mine design has been defined and amply described in previously-published work (1,2,4) -- likewise, the associated system of in situ instrumentation (3,4) and the computer modelling technique (2,3,4) which are the principal tools of this method. The present paper defines the procedure by which the in situ instrumentation and computer modelling cools are combined in adapting the general concepts of Stress Control to produce site-specific design solutions. This procedure is illustrated by means of case examples from three mines. The Stress Control Method utilizes the geometry of underground excavations, particularly through the time sequence of the creation of yielding pillars, to control stresses. The time sequence is devised such that all the primary stress envelopes are transformed into a single secondary stress envelope, surrounding the group of rooms separated by the yielding pillars. The secondary stress envelope provides protection to the roof and floor boundaries from all the external stresses. This stress relief effect removes the cause of roof and floor failure -- high shear stress in the weakly confined boundaries of underground openings. It thereby replaces artificial support with ground self-support, enabling simultaneous in¬creases in stability and percent recovery. Within limits which are still being explored and extended, the Stress Control Method has proven capable of overcoming the trade-off between stability and extraction ratio which has afflicted conventional mining methods. The application procedure of the Stress Control Method is outlined below in terms of the objectives, structure, and stages of a generic mine rock mechanics program for the site-specific adaptation of the time control yield pillar design technique.

Jan 1, 1984

By Bruce Hebblewhite

An ACARP-funded industry research project in Australia recently investigated the problem of premature rock bolt failures in underground coal mines. The project carried out limited sampling from 9 different collieries in NSW and Queensland, followed by a more comprehensive, controlled sampling from one colliery. Over 50 broken bolts were collected and subjected to metallurgical analysis at UNSW to determine both the steel composition and to analyse the fracture surfaces. Prior to this study, there had been anecdotal evidence of similar bolt failures from a number of sites within the industry. The sampling and analysis conducted by this project - whilst being below a statistically representative sample of the entire industry bolt population - highlighted the fact that bolt failures were continuing to occur at a number of sites, in both older and recently installed bolts. The failures were almost entirely attributable to stress corrosion cracking (SCC). It appears that a combination of factors - including steel composition, bolt manufacturing process, loading environment, geological and hydrological environment, bacterial corrosion - can all contribute to this problem. There is no simple solution, however, as with similar research findings from the UK, it appears that steels with higher values of fracture toughness, or Charpy Index, are less susceptible to SCC. Testing to date has been limited to bolt failures below the resin encapsulation horizon. A real concern is the potential extent of the problem at higher horizons, within the encapsulation. These may require some form of non-destructive testing (NDT) for detection. Initial trials in Australia of the ultrasonic device developed by DMT in Germany have proved encouraging. Further testing using this device is anticipated in future research. This paper describes the outcomes of the project, completed in 2002.

Jan 1, 2003

By Francis O. Blackwell

There are few industries in which power is more important to successful operation than mining, and none in which it is so difficult to ohtain power cheaply. Fuel is usually expeusive in mining districts, ana the ma chinery may be widely scattered and located in places difficult of access. The work is often so intermittent and variable as to prevent the economical use of steam. Mining operations are likely to exhibit accumulations of comparatively small and inefficient engines, numerous boilers and long lines of wasteful steam-pipes. Conlpressed air, as a means of transmitting power, is so handicapped by losses in the compressors and piping that it is limited to short distances and to the operation of apparatus requiring power, without regard to cost. To-day, electricity is rapidly replacing other methods of power-distribution, primarily because it is practically independent of distance. By selecting a potential proportional to the length of transmission, the cost of electric conductors and the e5ciency are the same for all distances within reasonable limits. For instance, a given amount of power can be delivered either 528 ft. away at 100 volts, or 50 miles at 50,000 volts, with the same total of copper per H.P. and with exactly the same loss of power in the transmissioo-circuk. This independence of distance permits the selection of the place most advantageous for power-development as a site for an electric power-plant, and the co~~centration there of the generation of all the power required within a radius of many miles. The powel.-site may be at a fall of water, if one is available, or a steam-plant can be built where fuel and supplies are cheapest, or where suflicient water is available for boiler-feed and condensing purposes.

Jan 1, 1904

By A. J. Keen

"Cominco's Polaris Mine is an underground lead/zinc operation located on Little Cornwallis Island in the Canadian High Arctic. Polaris is the world's most northerly base metal mine, situated at about latitude 75°N and longitude 97°W (Fig. 1). The closest community is Resolute Bay about 100 km to the southeast.During the construction and development phase Cominco adopted a unique scheme to save time and money. Many facilities including concentrator, powerhouse, shops and warehouse were built on a barge in southern Canada. The barge was towed 4800 km to the site in August 1981. Production at Polaris began in November 1981. The current mining rate is 1 million tonnes per year. The mine employs 250 people with about 190 on site at any time.GeologyThe deposit is a Mississippi Valley type orebody and lies near the top of the Ordovician Thumb Mountain Formation. Ore minerals consist of sphalerite and galena with the gangue being predominantly dolomite with calcite and marcasite. The orebody is situated completely within permafrost, consequently the voids frequently found in the ore are filled with ice. The orebody strikes north-south, dips approximately twenty degrees to the east and takes up an area about 400 m wide by 700 m long. The upper portion of the orebody (60 m to 150 m below surface) lies in an area called the Panhandle Zone. The deeper portion of the orebody known as the Keel Zone extends to 300 m below surface (Fig. 2). The deposit is strongly zoned with a high grade zinc/lead and iron-rich tabular core overlain and underlain by vein, stringer and breccia mineralization. The ore reserves at January 1991 were 14.6 million tonnes at 3.6% Pb, 13.7% Zn, 3.2% Fe, after producing 8 million tonnes at 3.9% Pb and 14.2% Zn since November 1981"

Jan 1, 1992

By Kathleen Lagnese, Srikanth Muddasani, Kashi Banerjee, Carla Robinson

"Mine water generated from underground coal mining operations contains both dissolved and particulate solids. Dissolved solids primarily consist of sodium, calcium, magnesium, potassium, chlorides and sulfates. When discharged to a receiving stream without treatment, these constituents create a potentially toxic environment for aquatic life.A case study is presented to discuss how a centralized treatment plant treats mine water from six locations to meet discharge limitations for chlorides. Located in West Virginia, this facility consistently achieves less than the National Pollutant Discharge Elemenation System (NPDES) permit limitation of 218 mg/L chlorides in the discharge while generating almost zero liquid waste. The dissolved solids concentration in the influent ranges between 5,000 and 10,000 mg/L, with chloride concentrations of 1,000 to 2,000 mg/L and sulfate concentrations of 2,000 to 6,000 mg/L.The mine water is treated using advanced treatment technology to produce clean water for discharge or reuse. The treatment process comprises aeration, softening, filtration, reverse osmosis (RO) reject softening, evaporation, crystallization, final effluent remineralization and sludge dewatering. The solid waste generated in the treatment process is landfilled on site. The leachate is sent back to the facility’s thermal treatment process. Because no liquid waste leaves the property, this plant is termed a zero liquid waste (ZLW) facility.The advanced water treatment system was built to meet a new 218 mg/L regulatory limitation imposed by the West Virginia Department of Environmental Protection for chlorides discharged to surface waters. The system is designed to treat a maximum flow of approximately 795 m3/h (5 million gpd) of mine water. The treatment process utilizes RO membrane treatment to achieve the effluent criteria, and evaporation and crystallization technology to manage the RO concentrate from the water treatment process. As a result, the system produces clean water for discharge while generating zero liquid waste. The effluent water can be used for industrial purposes or discharged to a receiving stream. A water impact index (WIIx) study indicated that discharge of this high-quality water into the Monongahela River watershed may improve the water quality for downstream water users. The waste produced in the treatment process, including softening sludge and salt, is disposed of in an onsite landfill. Currently, the plant is treating at an average flow of 490 m3/h (3.1 million gpd) of mine water with an average influent chloride concentration of 1,530 mg/L and an average effluent chloride concentration of 11 mg/L."

Jan 1, 2014

By Thomas J. Peters

The U.S. Bureau of Mines studied the 63,9SS-acre Hanson Lakes study area, including the Ten Mile-East and part of the Ten-Mile West RARE II areas, plus additional acreage, all proposed at times for Wilderness designation. The study was part of a Idaho Land Assessment Program with the Idaho Geological Survey and the U.S. Geological Survey, to provide minerals information for land-use decisions, and ensure domestic mineral supplies. The area is at the north end of the rugged Sawtooth Range and includes parts of the Sawtooth National Recreation Area which is closed to mineral location. The Copper Mountain. Elk Mountain, and Observation Peak mineralized areas are in the study area, but only Copper Mountain is open to claim location. It is on the trans-Challis fault zone and contains Tertiary granite which is favorable for mineral deposits of gold, beryllium, niobium, REE (rare-earth elements), tin, molybdenum, copper, silver, and lead. Identified resources are 1.9 million tons of flake graphite at Elk Mountain, but much more graphite occurs in the vicinity REE occurs in 18 black sand placer sites along the lower reaches of study area streams just outside the study area, on Cape Horn Creek, Marsh Creek, and lower Valley Creek flood plains, and at one hydrothermal site near Observation Peak. Hydrothermal REE is commonly low in? by-product thorium. a radioactive disposal problem. Many advanced REE applications enhance the quality of life, and future uses in superconductivity may reduce energy consumption. Seventeen lode, one geothermal, and 11 placer prospects were examined. Workings totaled about 20 adits, one shaft, several open cuts, and numerous small pits. Approximately 500 mining claims have been located or relocated in the study area, including a 200-claim block for disseminated molybdenum.

Jan 1, 1992

By G. W. Clark

"The mining of the ore bodies at Rabbit Lake has in the past been by the open pit method. This method is presently being used to develop the B-zone and will continue into the future with the development of two smaller ore bodies, the A-zone and D-zone. The Eagle Point orebody will be developed by an underground method which will provide production and employment into the next century.The ore bodies at B-zone, A-zone and D-zone are unique in that they are located under Wollaston Lake. To permit mining by the open pit method a steel-celled dyke has been constructed around the north end of the B-zone. This same dyking method will be used for the A -zone and D-zone. INTRODUCTIONMine development at Rabbit Lake commenced in 1970when a detailed engineering feasibility study established the viability of the Rabbit Lake deposit. In 1972 construction of the mill and camp site began. Construction materials were seasonally hauled to the site over a winter road until November 1973when the government of Saskatchewan completed an all-weather road to within six miles of the operation.In October 1974, stripping of the Rabbit Lake open pit began with the removal of overburden and lake bottom sediments from the previously drained Rabbit Lake. The first ore was processed by the mill in June 1975and by October the mill was producing three million pounds per year. The design capacity of five million pounds annually was first achieved in 1977 and maintained until 1981, when lower ore grades resulted in lower production rates .It was clear when mining at Rabbit Lake began that, without additional reserves, the Rabbit Lake operation had a life of less than 10 years. Exploration, therefore, continued in the immediate area in an attempt to discover additional uranium mineralization."

Jan 1, 1989

By W L. Daniels, C Stilson, C Zimmerman

Mineral sands mining for ilmenite, rutile and zircon has disturbed over 1000 ha of prime farmland in Virginia (USA) since 1997 and additional areas are likely to be disturbed in Virginia and North Carolina (USA) over the next 15 years. Full-scale mining operations at the Old Hickory Project in Virginia were initiated in 1997 by Iluka Resources Inc. and restoration protocols have continued to evolve in response to a variety of economic, technical and social issues. Early on, the return of these lands to agricultural row-crop production was complicated by vertical stratification of tails + slimes and lateral variability in soil physical conditions in the reclaimed pits and by limited topsoil return. Virginia Tech and Iluka have worked cooperatively with all stakeholders for over 20 years to review the pre-existing research base, conduct new and innovative site-specific research and thereby provide reasonable expectations of post-mining soil productivity levels. In 2004, Virginia Tech, Iluka Resources and a local leaseholder (Carraway-Winn family) agreed to jointly manage a 45 ha research demonstration farm where the long-term effects of alternative soil reconstruction practices are being rigorously monitored for both row crops (corn and wheat) and forage production. All mined land crop yields are also compared to an adjacent undisturbed exceptional quality prime farmland soil. Row crop yields between 2005 and 2010 were significantly above county average yields (regulatory target level) and approximately 75 - 80 per cent of undisturbed adjacent prime farmlands. The state regulatory authority has recently relaxed its position on the necessity of topsoil return versus use of topsoil substitutes based on appropriate on-site research results and the ability of the reclaimed soils to meet comparative local county crop yield targets. This cooperative effort allows all clientele groups to objectively assess the post-mining productivity of these mined lands while providing an invaluable educational opportunity for the mining industry. CITATION:Daniels, W L, Stilson, C and Zimmerman, C, 2012. Development of effective rehabilitation protocols for mineral sands mining in Virginia, USA, in Proceedings Life-of-Mine 2012 , pp 97-104 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 10, 2012

By James Yancik

The Howe Coal Company located in Leflore County, Oklahoma is mining the Oklahoma Lower Hartshorne Coal bed which ranges in thickness from 38" to 42" and dips approximately 7 degrees to the Northeast. The Lower Hartshorne bed lies within the Hartshorne sandstone in Oklahoma but is as much as 60 feet above this sandstone formation in Arkansas. This coal bed extends throughout the Arkansas Oklahoma coal basin, which is about 50 miles wide and 180 miles long and progresses from a semi anthracite in Arkansas to a low-volatile coal in the eastern part of the Oklahoma to a high-volatile coal in the western area. The Howe Mine #1 in the eastern area is mining a low-volatile bituminous coal which has been used as metallurgical coal since the early 1900's as evidence of Bee-hive coke ovens still remain near the town Howe, a few miles northwest of the mine site. The Howe Mine is the first mine in the area to use modern mining equipment, however, numerous punch mines have been worked along the outcrop south of the mine site dating from 1900 with the last closing in 1965. The coal characteristics of the Lower Hartshorne rival the Pocahontas seam in chemistry and coking qualities. This paper will be concerned with the preparation of the coal for the Japanese steel market. The three man crew necessary to operate the plant are the operator, the helper, and the equipment operator needed to feed the raw coal hopper. An additional equipment operator is available on the day shift for coal loading and moving the clean coal to the storage pile as the area under the clean coal belt is only large enough for 1 shifts production. We are at present running the plant on a 2 shift per day basis.

Jan 1, 1969

By R. L. Virta

Four companies ? H.C. Spinks Clay Co., Inc., Imerys, Old Hickory Clay Co., and Unimin Corp. ? mined ball clay in four states in 2013. On the basis of preliminary data, production was 1 Mt (1.1 million st) with an estimated value of $47 million. Production increased by 3 percent in tonnage from 973 kt (1.1 million st) with a value of $45.1 million in 2012. Tennessee was the leading producer accounting for 64 percent of domestic production, followed by Texas, Mississippi and Kentucky. About 67 percent of total ball clay production was airfloat, 22 percent was crude or shredded and 11 percent was water-slurried.

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's methane control research program, on the technology developed, and on the direction of further research.

Jan 1, 1986

By Guy Demers

"This paper defines the responsibilities and functions of the Maintenance Department, and its organization, physical and human assets, highlighting the unique operating problems. Due to the self-sufficient aspect of the Asbestos Hill Deception Bay project, the Maintenance Department cover-s fields that are numerous and very dissimilar: production, mobile, processing, service, power generation, fire protection, heating, water and sewage disposal equipment. Added to this, buildings, plant and camps, wharves and communications equipment all demand versatility, adaptability and expertise from maintenance personnel. Good maintenance practices are a necessity in this environment and are more critical than at southern locations; that is, high-quality replacement material, complete and well-controlled preventive maintenance, major repairs on a component-replacement basis, updated inventory, efficient training and permanent contacts with suppliers, combined with an equipment improvement program, updated specifications on lubricants, hoses, seals, filters, etc., are mandatory. The seasonal aspect of the operations applies a great deal of pressure on the maintenance team, as the production months do not permit major repairs. Short- and medium range planning and accurate evaluation of equipment conditions highly influence production efficiency. Maintenance control, planning and scheduling do not follow the accepted standard routines, as personnel turnover normally does not permit an accumulation of knowledge of the equipment history and condition by the •individual tradesman."

Jan 1, 1976