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By Morris Loshinsky, George Ziegler

NEW ROUTES - 63rd STREET CROSSTOWN The New Route construction along East 63rd Street in Manhattan began in 1969 with the East River tunnel connecting Manhattan and Queens. The 63rd Street Line, once in Queens, is planned to connect to another new route called the Queens By Pass or Super Express (See Exhibit 1) which would connect to the Queens Boulevard Line at Forest Hills. The purpose of the Queens By Pass was to alleviate subway congestion to and from the Borough of Queens, whose population had rapidly expanded during and after World War II. The existing Queens Boulevard subway lines (the "E" and the "F" trains) are almost filled to capacity at their terminal stations with passengers from Long Island. Passengers boarding trains enroute from the local Queens stations have difficulty boarding crowded trains, and, at times, cannot board the trains. The New Routes, thus, were to give additional train capacity into Manhattan and thereby relieve the crowded conditions along the Queens Boulevard corridor. PROFILE - METHOD OF CONSTRUCTION The portion of the New Route passing east-west under East 63rd Street on Manhattan (See Exhibit 2) had to snake beneath intersecting structures running north and south, such as the Con Rail tracks below Park Avenue and the 80 ft deep Lexington Avenue Express track structure along Lexington Avenue. Further, the Lexington Avenue Local tracks are in a separate structure which has a high profile close to the street surface. Therefore the 63rd

Jan 1, 1981

By G. Wang

Industrial minerals processing has gained importance lately, not only due to its wide range of new and regular applications in processing different industrial minerals, but also due to the strict specs under which products are commercialized. Among the processes applied to industrial minerals, flotation is a leading technology. The laboratory study and commercial operation demonstrate that the sulfonated reagents are very effective collectors for industrial minerals. This paper compares synthetic petroleum sulfonate with fatty acid on iron reduction in glass sand processing and describes the effect of conditioning pH on iron reduction using synthetic petroleum sulfonate as collector, the effect of molecular weight of natural and synthetic petroleum sulfonates on their flotation performance and the enhancement made for certain products.

Jan 1, 2011

By F. G. Schora

The Institute of Gas Technology (IGT), under sponsorship of the U. S. Department of the Interior, Office of Coal Research (OCR), and the American Gas Association (A. G. A. ), has been undertaking the development of one of several processes to convert coal to high-Btu gas as a means of supplementing natural gas supplies. It is anticipated that there will be a significant need for such gas in the foreseeable future in order to meet the ever increasing demands for this preferred fuel form. HISTORY The development of the HYGAS® Process is based on various studies conducted at IGT starting back as far as 1945. Initial work was directed toward production of synthesis gas with subsequent catalytic methanation. By 1964 the concept of the direct hydrogenation of coal to produce methane noncatalytically was well-founded and the chemistry was reasonably well established. Work up until this point in time was financed by the American Gas Association. In 1964 the U. S. Department of the Interior, Office of Coal Research joined with A. G. A. to support the program. The objective at that time was to develop the necessary know-how to enable the design of a pilot plant, a necessary step in the ultimate commercialization of the process. Work for the next three years (1964-1967) emphasized investigation of fluidized-bed technology in the hydrogasification step, where moving-bed technology had been previously employed, as well as identification of commercially available catalysts acceptable for catalytic methanation of the CO and hydrogen in the hydrogasifier effluent under operating conditions in the system. By 1967, the preliminary design of a 3 ton/hr pilot plant had been finalized, and IGT received authorization from OCR to proceed with the detailed design and construction of that facility. The pilot plant was designed to study the following problems:

Jan 1, 1972

By Tim O’Neil

Many mining companies try to fight their way up from small operator and exploration company to major producer. Not many companies make it. Cambior Inc., formed in 1986, is one company well on its way to making it as a major operating company. In 1993, Cambior surpassed 15.5 t (500,000 oz) of gold production and began operations at its world class Omai gold mine in Guyana. At the same time, the company has embarked on a program of geographic and minerals diversification. Cambior, a Canadian company, now has interests in eight mines, three development projects and more than 100 exploration properties in North and South America. The company’s goal is to derive 70% of its income from gold and 30% from base metals and other minerals. Cambior’s moderate diversification into base metals gives protection against negative gold price fluctuations. It also balances the typically short term gold mines and the longer term base metal mines.

Jan 1, 1994

By D. Berberick, G. Sturgis, M. Board, B. Strickland

"Hecla Limited is nearing completion of the Lucky Friday Mine No.4 shaft located in Mullan, ID. The shaft is collared at the 4940 level of the mine and will have a final mine level depth of 8620, or 9,590 feet below the surface. After reaching the 7400 mine level the shaft encountered ground deformation higher then allowed for in the design for a circular shaft excavation and concrete lining. This additional ground deformation required portions of the shaft concrete liner to be reinforced with frameless, steel liner plate. To eliminate the installation of the liner plate from the remaining shaft development, the design of the shaft excavation starting at the 7650 mine level was changed to an elliptical cross section based on the overall stress field orientation as well as the orientation of the structure of the host rock surrounding the shaft. The elliptical cross section was instrumented to confirm the shaft excavation and lining was performing as designed. This design change has allowed the shaft to continue to the planned 8620 mine level without the need to install liner plate in the shaft or change the overall functionality of the shaft or the Lucky Friday life of mine plan.INTRODUCTION Hecla’s Lucky Friday Mine is a deep, underground producer of silver, lead and zinc in the Coeur d’Alene mining district of northern Idaho (Figure 1). Primary access into the mine is via the Silver Shaft, a 5.5-m (18-ft) diameter, concrete lined shaft sunk to an original depth of 1,890-m (6,200-ft). Current production is from the Gold Hunter vein system, approximately 1,525-m (5,000-ft) northwest of the Silver Shaft.Lucky Friday’s #4-Shaft is a 5.5-m (18-ft) finished diameter, internal shaft, or winze, being sunk to the north of the Gold Hunter vein system, from the mine’s 4760 level, 1,743-m (5,720-ft) below the surface, to the 8620 level, 2,923-m (9,590-ft) below the surface. The shaft is designed to provide access to the deep, high-grade zones of the Gold Hunter in order to increase the mine’s production and operational life. Design and engineering began in 2006, with construction starting in the fourth quarter of 2009."

Jan 1, 2016

By Xinchun Li, Youdi Zhang

AI is one of the computing methods, artificial intelligence performs its calculation by simulating the intelligent behavior of human beings. It is regarded as one of the most important scientific achievements in the 20th century, A1 has been developed rapidly in recent years with the development of the computer technique .The application of AI in the mineral industry has also obtained rapid progress sine AI has been used in early 1980's, such as evaluation of resource, underground mining, surface mining and mine safety etc. It has played an important role for increasing mining efficiency, improving mining management and ensuring the safety of the miner. An integrated A1 system has been developed for coalmines environment management in this paper.

Jan 1, 2002

By T. J. Fenner

Research conducted in South African mines has demonstrated the benefit of ground penetrating radar for the detection of geologic features and hazards. This is crucial for safety and production considerations in underground mines that are as much as 4 kilometers deep. This paper describes a new ground penetrating radar system designed specifically for high quality data acquisition, in the harsh conditions of deep underground environments, for use by operators with minimal geophysical experience. Design criteria included automated functions, intrinsic safety, light weight and minimal power requirements. Data is processed on the ground surface by geoscientists using a PC.

Jan 1, 1994

By Reed S. C. Rogers

The most widely used machines for grinding coal to the sizes prescribed for the pulverized coal firing of furnaces, boilers, and kilns are the vertical ball-race, roller-race and roller-bowl types of mills. However, the increased use of coal has led to an increased use of tumbling ball mills for coal grinding. Specifically, air-swept ball mills are now a part of many dry pulverized coal firing systems, offering the advantages over vertical mills of lower maintenance costs and the ability to handle strong or abrasive (high ash) coals. The current use of wet ball mills is to prepare coal-water slurries for direct combustion, although in time they may also find routine application for preparing slurry feed for coal gasifiers. In either application, wet ball mills ofer the advantages that coal grinding and wetting can be accomplished in a single step, and that the mills are readily used with fine wet screens to assure top size control in the slurry product. The simulation of tumbling ball mills with mathematical models has reached a fairly advanced stage, but the concepts have been applied only recently to coal grinding. As this paper will demonstrate, however, significant progress has been made in the use of models in ball mill circuit design for coal grinding. Included is a description of the techniques used for simulation, recommended parameter estimation methods, and demonstrations of process engineering calculations for large scale coal grinding circuits.

Jan 1, 1986

By Yoginder P. Chugh

About 65% of the U.S. coal production (835 n tons was surface mined. A similar proportion of the Illinois basin's production (112 m tons) is also surface mined. The state of Illinois is the third largest producer of surface mined coal in the United States, after Wyoming and Kentucky. The Illinois coal basin encompasses Illinois, southwestern Indiana, and western Kentucky, as shown in Figure 1 (dotted lines). The estimated surface mineable coal resources in the basin amount to about 27 billion tons, and about 69 m. tons of coal is surface mined annually (Tab1e I).

Jan 1, 1981

By Thomas D. Henderson, Wayne R. Hopkins, Arthur Lynch

Brought on stream in 1975, the 10,000-tpd copper oxide processing plant of Anamax Mining Co. at Twin Buttes, Ariz., is now at design capacity. Based on acid agitation leaching, solvent ion exchange, and electrowinning, the Anamax plant bridges an ore to metal gap by producing mine site copper cathodes from lime-bearing oxidized feed. Until recently, such material was considered submarginal because copper recovery was uneconomic using conventional methods. The new Twin Buttes oxide plant, the largest of its kind in North America, is one stage in the expansion of Anamax, a joint venture owned equally by The Anaconda Co. and Amax Inc. Other phases include an accelerated stripping program in the pit, an expansion of the sulfide concentrator from 32,000 to 40,000 tpd, and construction of a 57 MW diesel generating station for the oxide plant. Once the basic oxide flowsheet had been selected, Anamax awarded a contract to a joint venture of Arthur G. McKee and Co.' (Western Knapp Engineering Div.) and Davy Powergas' (a member of the Davy International group). The contract covered process design, engi¬neering, procurement, and construction. The property, identified by Banner Mining Co. in the 1950s and developed by Anaconda, was put into production in 1965 as an open pit mine equipped with a 32,000-tpd sulfide flotation concentrator. The Twin Buttes mine has since become one of the largest earth¬moving operations in the world, excavating some 10 tons of waste per ton of ore. At the original sulfide mill feed rate, the mining fleet moved 375,000 tpd of material (225,000 tpd alluvium and 150,000 tpd of rock). The most significant copper mineral in the ore body is chalcopyrite, which is scattered in pockets of weak mineralization. Cap oxidation has progressed to depths of several hundred feet, principally as chryso¬colla. Present estimates place minable reserves at 347 million tons of sulfide ore grading 0.6% copper and 55 million tons of oxide ore grading 0.9% recoverable copper from 1.25% total copper. The nonre¬coverable fraction is composed of native copper and insoluble copper oxides and sulfides. The oxide ore has been partially stripped, and 25 million tons having a copper content greater than 0.6% have been stockpiled. The stripping of oxide ore to expose sulfides will continue for several years. The copper oxide studies launched by Banner Mining in the 1950s were continued by Anaconda. Process routes investigated included: acid leaching; cyanide leaching; segregation roasting; chlorination, oxidation, and reduction; flotation in combination with leaching; cal¬cite flotation plus leaching; copper oxide flotation; and sulfidization flotation. By late 1968 test work favored a low temperature roast followed by an ammonia-ammonium carbonate leach of the ore. During this period, acid leaching had been discounted because of excessive con¬sumption of expensive acid by the high limestone ore matrix. Restric¬tive SO2 emission controls in 1971 suggested an increase in acid production and availability at a lower cost. Research then switched to acid leaching, resulting in development of the present flowsheet. Mechanically agitated leaching in a cascaded series of tanks was selected in preference to vat leaching after piloting a stirred-tank system. Preliminary testing of vat leaching indicated that inter-vat solution clarification problems could be caused by gas evolution from leaching of high limestone ore. Lack of research time for resolution of this problem, plus success of the pilot agitation system, dictated the final flowsheet selection. In 1973 Anamax decided to proceed with agitation acid leaching to produce liquor for a solvent ion exchange (SIX) and electrowinning (EW) installation. At that time, such systems were proving their eco¬nomic viability, and they allowed direct recovery of high quality cath odes while bypassing the smelting and refining of lower grade cement copper precipitates. The Anamax oxide plant processes a grade of about 1% recovera¬ble copper from stockpiled sources and new mine production. Unit operations include size reduction, agitation leaching, countercurrent decantation washing of residue, pH adjustment of solution, clarifica¬tion, solvent ion exchange, and electrowinning of copper, with a mini¬mum of environmental impact. The feed to the primary crushers is composed of: 1) -10-in. stockpiled oxide ore, which has passed through the mine crusher and has been grade-segregated to allow blending for a consistent feed material. 2) -4-ft ROM oxide ore stockpiled in the early mining operation. 3) -10-in. ore currently being mined. Ore is delivered in 100-ton mine trucks to a dump pocket, where an apron feeder transfers the ore to an inclined 6-in. fixed grizzly. The grizzly oversize passes through a 48 x 60-in. primary jaw crusher, where it is reduced to -6 in. The fixed grizzly undersize and the crusher product are conveyed to a 4-in. vibrating grizzly. Oversize from this grizzly reports to a 7-ft Standard cone crusher, where it is reduced to -1 in. The crusher product and the vibrating grizzly undersize are conveyed to two 8 x 20-ft double-deck vibrating screens that operate in closed circuit with two 7-ft short head cone crushers. Screen undersize (-1/2 in.) is delivered to a covered conical fine ore stockpile with a designed live capacity of 15,000 st. Beneath the stockpile are ten Pioche belt feeders feeding two conveyor belts that supply the milling circuits. Each group of five feeders has two variable speed and three fixed speed drives. Grinding to 95% -48 mesh is done in two parallel lines, each consisting of an 111/1 x 18S -ft rod mill and a 12' x 30-ft ball mill in open circuit. Water is added to maintain a pulp density of 72% solids in the mills. Further water additions are made to the ball mill discharge sumps to create a 60% solids slurry for transfer to the leaching reactors. The nominal grinding rate is 440 tph solids. A splitter box on the product from the mills separates the incoming slurry into two streams, one for the leaching reactors and the other for the pH adjustment reactors. This split is determined by the lime content of the feed material and the pH of solution entering the pH adjustment reactors. Five 30-ft diam by 31-ft high mechanically agitated, rubber-lined leach tanks are arranged in cascade, with gravity transfer from one to another by enclosed launders. Concentrated sulfuric acid (93.2%) from storage is added to the pulp principally at the first leach tank, and the reacted slurry leaving the cascade after a 5-hr residence time at 50% solids is pumped to countercurrent decantation (CCD) wash thickeners.' At this point, most of the soluble copper has been leached from the ore. Up to 250 lb of sulfuric acid is consumed per ton of ore, the acid being supplied in tank cars from a nearby smelter. Leached slurry at 50% solids is washed countercurrently with return raffinate from the SIX plant in a series of four Doff-Oliver center caisson, 400-ft diam thickeners. Solids advance from thickeners No. I through No. 4 to the tailings dam. SIX raffinate advances from thickener No. 4 to thickener No. l, where a pregnant solution overflows to pH adjustment. To optimize solvent extraction, the pH of the pregnant solution from CCD thickener No. I is adjusted from 1.5 to 2.5 by adding unreacted ground slurry (split from the grinding circuit) to the preg¬nant overflow of No. I CCD thickener. The resulting slurry is retained for 45 min in three mechanically agitated leach tanks. CO, generated during leach and pH adjustment is ducted to a demister, where entrained acid droplets are removed. The cleaned CO, and the No. 4 CCD underflow are the only effluents from the plant. The underflow of No. 4 thickener mixes with tailings from the sulfide concentrator and is neutralized. Slurry exits the pH adjustment vessels at about 10% solids and

Jan 1, 1985

By D. J. Benton, S. Finley, D. T. Orr, A. J. Chambers, M. A. Stepan

"Corrosion of ground support can lead to falls of ground that pose a significant risk to miner safety. To address this problem, the National Institute for Occupational Safety and Health (NIOSH) is investigating corrosion at the Hecla Mining Company’s Greens Creek Mine, located near Juneau, Alaska, USA. Field studies have used photogrammetry surveys to document welded-wire mesh corrosion, and laboratory studies at NIOSH’s Spokane Mining Research Division (SMRD) have investigated the effects of corrosion on ground support integrity. Findings show that (1) corrosion monitoring through photogrammetric methods may be effective for qualitative measurements of welded-wire mesh corrosion, and (2) there is a relationship between loss of load-bearing capacity and the diameter loss due to corrosion in welded-wire mesh. Photogrammetry results thus far have measured an apparent bulking of the corroded welded-wire mesh, and preliminary laboratory tests have investigated the relationship between the larger bulked and effective wire diameter. If this relationship is verified, these results may indicate that photogrammetry, when combined with the models produced in laboratory tests, could offer a means of monitoring corrosion levels, as well as rock rib deformation. INTRODUCTION Reducing the number of rock fall injuries and fatalities is an important part of the mission of the National Institute for Occupational Safety and Health (NIOSH) Spokane Mining Research Division (SMRD). Ground control using support systems to protect miners from rock falls is one of the oldest mining sciences, and considerable research has led to a variety of modern tools and methods in use today. Among these tools are rock bolts and welded-wire mesh, which are made from increasingly higher-strength steel grades to meet the increasingly demanding requirements of underground mines [1]. However, the benefits of these higher-quality support elements may be negated in corrosive mining environments. A better understanding of how corrosion affects the support capacity of ground support systems will assist engineers in determining when an opening is at a greater risk of falls of ground. Accelerated corrosion has been occurring in some areas of the Hecla Mining Company’s Greens Creek Mine near Juneau, Alaska, USA. Corrosion of ground support has resulted in two falls of ground occurring between April 2015 and March 2016. While these falls of ground did not injure any personnel, mine management recognized the high risk to miner safety and responded by actively undertaking a ground support rehabilitation program. Rehabilitation measures include the installation of both galvanized and coated, corrosion-resistant bolts and welded-wire mesh, depending on local conditions."

Jan 1, 2017

By William Wargo

The basic reason for lining underground cavities is to keep the cavity open during its useful life by providing adequately for the support of the surrounding rock and for the necessary degree of water tightness. This covers the entire field of support methods from the simpliest timber support to reinforced concrete in all its variations as applied to tunnels, galleries or shafts. The problem involved in the design of more efficient and economical lining systems for even bigger cavities has been magnified by increased speed of advance made possible by better blasting tecniques, improved tunneling machines and more efficient material handling. Tunnel lining today requires a disproportionate amount of time and money compared to other operations mostly due to the manuel labor involved in its installation. One solution to this problem is the developement of an entirely new concept in tunnel lining designed notoonly to overcome this bottleneck but also to open up the field for further increases in speed of advance. This new lining system acts first as a fast protective armour then becomes the concrete metal form and ends up as reinforcement sheet inside the concrete lining. This system developed and manufactured by Bernold A. G. of Switzerland since October 1968 has been installed in 25 applications in Europe under all ground conditions from stable rock to unconsolidated ground.

Jan 1, 1970

By D. M. Muir

Thiosulfate offers a nontoxic alternative to cyanide for processing gold ores. The mechanism of leaching gold using ammoniacal thiosulfate solution is driven by the Cu(II)-Cu(I) redox couple and is complicated by competing ligands such as NH3 and S2O32; It is shown that an understanding of the copper speciation and sulfur speciation is required to optimize this system. This paper presents Eh-pH and speciation diagrams for varying concentrations of Cu(II), S2O32- and NH3 and discusses the conditions under which various copper and sulfur species are stable.

Jan 1, 2002

By J. F. McDonald

On December 8th of last year, the new St. Clair River tunnel was holed-through to Port Huron, Michigan. The tunnel, commissioned by the Canadian National Railway, was needed to replace an existing tunnel that had been built between 1889 and 1890, and had remained in continuous operation until the new tunnel was opened to traffic in April of this year. The original tunnel, after more than 100 years of service, was still structurally sound, but was too small to accommodate the double stacked container cars and other advances in the railroad's equipment that had developed over the years. Prior to the construction of the first tunnel, all freight was barged across the river. It was a slow, expensive process, which in winter was sometimes impossible. The nineteenth century tunnel was built in twenty months, utilizing two shields that mined to the middle from each end. The lining, which is still in excellent condition, consisted of bolted, cast iron segments, with an O.D. of 6.4 meters. It was the first sub-aqueous tunnel built in North American, and it's use of compressed air under the river and hydraulic power on the shields may also have been firsts. The digging was done by hand, and the muck hauled out by mule drawn wagons. Boulders and methane gas were reported to be a constant problem during the drive, and compressed air sickness was common, but when the two shields came together in August of 1890, it was reported that the alignment was within 6 mm. The new St. Clair River Tunnel was constructed for basically the same reason as the original. The larger equipment which the railroad is using today would not fit through the old tunnel, and once more they were forced to ferry the cars across the river.

Jan 1, 1995

By C. L. Karr, E. J. Gentry

Researchers at the U. S. Bureau of Mines have developed a control algorithm to efficiently manipulate chaotic systems. The control, based on both fuzzy logic and genetic algorithms, prescribes actions that drive the chaotic system to acceptable regions of state space. The use of fuzzy logic enables a person who has limited experience with a chaotic system to establish a set of rules for manipulating the problem environment, and a set of membership functions that define terms used in the rule-set. Genetic algorithms are search algorithms based on natural genetics, and are used in the control algorithm to select membership functions that provide for a suitable level of control. The Bureau-developed algorithm controls the computer simulation of a ball bouncing on an oscillating table, a system that exhibits chaotic behavior.

Jan 1, 1993

By B. Stewart, R. Li

Coal waste materials inhibit the direct establishment of vegetation due to adverse physical and chemical properties, particularly low water retention and high potential acidity. The Moss #1 coal refuse pile is located in Dickenson County, Virginia, and was idled in the late 1980s with little topsoil resources available for final closure. The refuse was acidic (Total S = 0.38%; pH = 3.6), black in color and high (70%) in coarse fragments. The refuse also had a low water-holding capacity (4.5% in < 2.0-mm fraction). A small plot experiment was established on the refuse pile to evaluate the effects of liming rates (50% and 100% of lime requirements) and topsoil thickness (15, 30 and 60 cm) on vegetative growth and leachate quality. Liming and topsoil amendment increased the surface soil pH from <4.0 to >6.0 over a two-year period, which resulted in greater vegetative cover and biomass than the control plots. All topsoil treatments resulted in greater vegetative cover and biomass than plots treated with lime only. This was due to improved surface soil physical and chemical properties. A topsoil treatment of 60 cm gave the thickest vegetative cover and biomass yield. Such a treatment, however, would be cost-prohibitive at this location. Applica¬tion of 27Mg ha`1 of lime to the refuse surface along with 15 cm of topsoil produced acceptable two-year vegetative cover and biomass, and this appeared to be the optimal treatment for this particular situation. Both liming and topsoil had no affect on leachate pH and the electrical conductivity of leachates collected below the plots. This suggests that surface revegetation will have little effect on the quality of water draining through the pile. Therefore, long-term water-treatment requirements may not be reduced by successfully revegetating the pile surface.

Jan 1, 2000

By Stephen G. Whittaker, Rosalind A. Schoof, Martha J. Steele

In determining remedial action objectives for metals in soils, the U.S. Environmental Protection Agency typically assumes that the metal concentrations in house dust are the same as the metal concentrations in soil. Data now available from several studies that were conducted in mining communities suggest that for some metals, concentrations in house dust may be lower than those in soil. This paper reviews available data on the relative soil and indoor dust concentrations of arsenic and cadmium and examines how changing assumptions regarding indoor dust concentrations of arsenic affects risk assessments and determination of cleanup levels.

Jan 1, 1992

By Joel D. Hammond

Lightweight concretes date back to before the Roman Empire. The earlier concretes were made by combining a burnt lime for cementious material with pumice or volcanic rock for aggregate. Although structural value was limited due to its primitive nature, many structures were able to withstand the test of time. The rotary kiln expanded shale industry had a slow start that began around 1908. The industry was founded by Stephen J. Hayde of Kansas city, Missouri. Mr. Hayde noticed that the bloating effects of some aggregates were undesirable by the brick industry. Material of this type was considered waste and avoided in brick production, but he realized it had all the qualities and basic requirements for a concrete aggregate that would reduce weight and still retain structural value. It came into national attention by use in ocean-going vessels through a shipbuilding program undertaken by the united states Fleet Corporation. This research was brought about by the need to find a suitable material to replace high-grade plate steel due to a shortage created by World War I. The need prompted the government to supply the reserves that Stephen Hayde desired to continue and complete research into producing a uniform lightweight aggregate. His results pointed to the rotary kiln method for which he was granted a patent in 1918. One of the most famous and largest concrete ships built through this program was the U.S.S. Selma. Although the Selma

Jan 1, 1977

By M. P. Adamson, Bryson D. Trexler, R. V. Ramani, Mark L. Koenig, V. Rajaram, Alan Burton, C. S. Crocker, Kim. Y. C., A. G. Law, William C. Larson

Another record year vas experienced by the mining industry as the value of nonfuel minerals production soared to $23.5 billion-up 15% from the previous year. Based on preliminary estimates by the Bureau of Mines, US mine output was the basis for about $225 billion worth of minerals-derived materials. Metal mining accounted for $8.5 billion, or 36%, of the total. Of the 22 metals produced in the US, 11 showed quantity increases, while 16 had value increases. Business Week&apos;s survey of 1200 companies (Mar. 17, 1980, pg. 81) revealed that 21 metals and mining companies had sales increases of 30% with earnings up 104%. Higher prices and increased demand for metals were primary factors behind the improved performance. The steel sector reported a 30% decrease in earnings for the year, but the slump was primarily the result of a $383-million loss for US Steel coupled with a 17% decrease in earnings at Inland Steel. Other firms did well in 1979, with earnings up 279% at Interlake and 269% at Kaiser Steel. Major obstacles facing the steel industry included substantial tonnages of dumped and subsidized imports, environmental expenditures, runaway inflation, and price controls. Turning to nonmetallic production, of the 49 commodities reported by the US Bureau of Mines, 29 had higher outputs and 39 had increased values. While production statistics may seem encouraging, government regulations continued to stifle industry efforts to develop needed new capacity. A case in point may be publication of the Environmental Protection Agency&apos;s simplified procedure to streamline five permit programs by consolidating them into one. The five included: hazardous waste management, national pollution discharge elimination, dredge and fill, underground injection control, and prevention of significant deterioration. The new procedure, published by EPA in the Federal Register, took 149 pages. AMC&apos;s J.A. Overton, Jr., noted that (MCJ, Nov. 1979, p. 39) to visually depict the complexity of the proposed regulations, Sell Oil Co. developed a flow chart mapping a path through one section. The chart required 10 days to map and two weeks for two draftsmen, using computerized drafting techniques, to plot the results. Overton said, "Perhaps the greatest service EPA has performed in preparing its proposal is to demonstrate again that federal regulations have become a complexity compounded by confu¬sion that culminates in a conundrum." While regulatory agencies promulgate new regulations, the lack of a cohesive government minerals policy remained a matter of significant importance to mine management. A non-fuel minerals study to provide input to the Administration for a national minerals policy program was a dismal shock, according to Rep. Jim D. Santini (D-NV). He said the first phase of the program, which was to identify industry problems, failed to come to grips with the hard decisions necessary regarding these problems, their impact, and their interrelationship. Santini said the report failed to acknowledge government&apos;s role in the process and absolved the government of any adverse influence on the domestic minerals industry. In response to the phase one report, eight senior mining executives testified before Santini&apos;s House Subcommittee on Mines and Mining concerning mineral supply, access to foreign sources, environmental protection, conservation and recycling, national security, and capital formation. By year&apos;s end, Rep. Santini promised to prepare a hard-hitting committee report on problems affecting the non-fuel minerals industry to provide a better base for subsequent policy recommendations (MCJ, Jan. 1980, p. 34). On the technological front, interest again centered on mechanization, automation, and scaleup to improve and expand production. Computer use increased for calculation of ore reserves, mine planning, operations research, and mineral processing.

Jan 5, 1980

By R. L. Wiegel

There are approximately 40 million tons per year of phosphate rock produced in the United States, half of it by flotation. The bulk of this is used to produce diammonium phosphate, an essential ingredient in the commercial fertilizer mixes used by the thriving U.S. agricultural community. This paper describes the mineral beneficiation practices of the phosphate industry, with special emphasis on flotation. There is also an attempt to include those items that might be considered emerging technologies for the industry as it faces the problems of a diminishing high-grade reserve and the necessity for implementing dolomite/francolite separations.

Jan 1, 1999