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By Sun K. Kim

Hydrometallurgical processes are not free of environmental regulations. A clear understanding of the regulations under which the minerals industry operates delineates processing requirements at early stages. This paper deals' with federal environmental regulations with emphasis on the hazardous waste regulations promulgated in May, 1980. The procedure of EP toxicity test and an example of the test are described. Brief account is given of the current trend and future outlook of regulations.

Jan 1, 1982

By D. C. Hatch

At the MacIntyre Development of the Titanium Division of National Lead Company a magnetite-ilmenite ore together with gabbro-anorthosite waste is mined from an open pit by shovels and trucks. The ore from the pits is trucked to ore stockpiles for blending ahead of the crusher and to free the mine from crusher delivery schedules. The ore stockpiles are blended to yield a 16.5 to 17.0 % TiO, crusher feed. This requires mining on an assay cut-off rather than a visual grade cut-off. Highly mineralized ore runs from 20 plus % TiO2 and 30 plus % Fe to 15 % TiO2 and 40 plus % Fe as the ratio of ilmenite to magnetite changes. There are three major ore types in the present pit with magnetite ratios varying from about one to one up to three times as much magnetite as ilmenite. Ilmenite and magnetite together liberate from gangue down to about 10 mesh and this is the basis of the magnetic cobbing. Below 10 mesh the ilmenite and magnetite start to separate and ore cobbing pulleys will not hold the ilmenite.

Jan 1, 1968

Conditional simulation provides a model of the ore body that represents variability in the data. This can be used to determine the impact of various grade control and mining strategies. A number of transfer functions are discussed that assist in optimizing grade control sampling. The cost effectiveness of various drilling and trenching techniques are discussed. Modelling of the expected performance of a mill head grade sampler is investigated. Conclusions are drawn about the likely impact of various sampling techniques on the economic performance of an operation and about applying sampling theory to grade control sampling.

Jan 1, 1999

By Jurij Karlovšek, Marko Žibert, Scott Keniston

"SUMMARY The importance of information management was recognised in surface construction industry decades ago, and has increasingly being recognised through formal process and laws. Around the world, these laws and codes of practice are currently being drafted and enacted, to reflect the development of software tools and corresponding increasing adoption by industry. This paper deals with specifics of implementing information modelling in tunnelling business utilising BIM (Building Information Modelling) technology developed for buildings as well as similar technology developed for mining industry. Although BIM is recognized initially as a 3D digital representation of physical and functional characteristics of a facility, the real benefits come when complex capability through construction sequencing and even detailed programming (4D) and cost capabilities (5D) are included. INFORMATION MODELLING The Architecture, Engineering and Construction (AEC) industry requires the production of design and construction information, which involves the input from several teams. The tasks allocated to each team need to be carried out in a particular order and coordinated in order to benefit all those involved and the project itself; this is known as “collaborative working”. To ensure the quality, and guarantee that information can be used without change or interpretation, working processes and standards needs to be agreed upon or else it will hinder collaboration and have a negative impact on project delivery. Case studies show that the additional capital delivery costs due to uncoordinated, inaccurate and ambiguous information amounts to 20-25%. The solution to overcome these problems and improve collaborative working in a project is the adoption of BIM. It is a modern approach to the design, documentation, delivery, and life cycle management through the use of project information databases coupled with object-based parametric modelling. BIM requires traditional practices shifting from simple drafting to using 3D native models for building design environment. Additionally, it requires that models are equipped with information that has been traditionally decoupled in a text or other kinds of documents. The goal is not in creating a 3D graphic representation of design intent; rather, it is a comprehensive information management tool based on the simulation of design and construction build around a central repository."

Jan 1, 2016

By M. Kehnemuyi

The U.S. Department of Energy is charged, by federal law, with the responsibility for developing and implementing programs for long- term storage and terminal disposal of high- level radioactive wastes from both commercial and defense nuclear operations. Approximately 288,000 cubic meters of defense high-level wastes are currently in storage at the government's Hanford Reservation in the State of Washington, the Savannah River Plant in South Carolina, and the Idaho Chemical Processing Plant in Idaho (U.S. Department of Energy, 1980a). High-level wastes from commercial nuclear power production are stored in water pools or basins at various power plant sites. At the end of 1980, approximately 7.460 metric tons of uranium, contained within 28,300 fuel assemblies was in storage at various reactor basins. Although the present inventory of defense wastes are many times larger in volume and in total level of radioactivity than the commercial wastes, in the future, the latter will constitute a substantial quantity of wastes that will have to be disposed of. The present electric generating capactiy of nuclear power plants in the United States is 56.5 Gigawatts-electric (GWe). The amount of spent fuel that would be discharged and accumulated by the year 2000 from these operating reactors would be 38,000 metric tons. With a projected growth of the nuclear industry to 180 GWe in the year 2000, the amount of spent fuel accumulated at the turn of the century could reach 89,000 metric tons of uranium or approximately 318,000 assemblies. In any case, whether one postulates a no growth pattern or one where nuclear power provides its share in the country's electric generating capacity in the next two decades, a means for safe and environmentally accept- able disposal of high-level nuclear wastes must be found. Storage of commercial wastes in water basins, either at reactor (AR) sites or at away from reactor (AFR) sites, and storage of reprocessed defense wastes in surface or near surface tanks is a temporary solution and is not an alternative for permanent disposal.

Jan 1, 1981

By M. K. McCarter

In 1963, a major expansion program at Kennecott's Bingham Canyon mine converted rail operation in the upper portion of the pit to truck haulage. Since that time truck-haulage capacity has increased to about 272 000 Mg (300,000 tons) per day. The majority of this production is waste material which is deposited in monolithic dumps located on the eastern slopes of the Oquirrh Mountains. The largest of these dumps, referred to as Copper Notch and Keystone, measures approximately 1830 m (6000 ft) in length, from 180 to 300 m (600 to 1000 ft) in height, and contains some 430 Tg (470 mil lion tons) of waste. The height, structure, rapid rate of growth, and anticipated leaching suggested the possibility of dump failure. In order to evaluate this possibility, an outside consulting firm was retained in 1966 to investigate the stability of the growing dumps. Their investigation indicated that, other than superficial movement, the waste dumps would be stable under static loading, and that soil distribution was not continuous enough to sustain massive foundation failure. Since this investigation, however, several failure processes have been observed. Crest settlement occurs frequently in response to compaction and over-steepening in the upper portion of the dump surface. Over-steepening results from accumulation of fines near the crest caused by natural segregation. Normally, coarse material, near the base of the dump, exhibits an angle of repose near 0.65 rad (37"). The fine material, however, stands as steep as 0.75 rad (40"). Periodic equilibrium adjustments cause stepwise settlement (Figure 1) of the dump surface and occasional sloughing of the protective berm. Routine surface preparation by dozers and graders and frequent inspections by supervisory personnel have proven adequate in preventing problems associated with this form of crest instability.

Jan 1, 1976

By James J. Scott

Friction Rock Stabilizers, trade name II Sp 1 it Sets'" have been under research and development by the author and the Ingersoll-Rand Company since February of 1973. The United States Bureau of Mines and the Mines Enforcement and Safety Administration as well as many mining companies have cooperated in field testing the device. Split Set rock anchors are distinctively different from the widely used mechanical rock anchors or fully grouted rock anchors. They control ground movement internally in a manner that allows controlled deformation during the early phase of the ground reaction curve but then, as secondary creep develops, anchorage per unit length increases and they serve to strengthen and stabilize the opening for long periods of time. The history of research and development of the Scott Split Set rock anchor system with accompanying laboratory and field test data is presented in this paper.

Jan 1, 1977

By James J. Fallon

I'm glad this meeting is being held in New York. First, because the city is close to my home in New Jersey, only 35 minutes from Times Square ..... if I were to come to Times Square between two and three in the morning. Otherwise it takes two hours. But even more important is the fact that all of you good people from around the country and around the world will enjoy the unique experience of that warm friendly atmosphere in the greater metropolitan area, something that you won't see any place else on the face of the earth. Seriously, the greater metropolitan area has been a large part of my industrial, cultural and spiritual experience. There are many aspects of it which I find disagreeable but on net I would rather live in this area, at least for the time being, than any other area of the United States. As a consultant I find contact with financial institutions, corporate headquarters, information sources and a great many production and research facilities a valuable asset to my activity.

Jan 1, 1985

By James K. Kindig

Hazen Research, Inc., has developed a new process for removing pyritic sulfur and ash from coal. Feed coal is contacted with iron carbonyl vapors, Fe(CO)5, at 190°C which puts a thin skin of magnetic material on the pyrite and ash, but does not affect the coal. Thus, low intensity magnetic separators yield a nonmagnetic coal, low in sulfur and ash, and a magnetic refuse, high in sulfur and ash. Results are given for clean coal produced by this method. A comparison is made between results of the magnetic process and the U. S. Bureau of Mines two-stage flotation process cleaning identical samples of Pittsburgh Coal. Capital and operating costs of the two cleaning methods are discussed.

Jan 1, 1976

By J. R. Iwinski

Escanaba, Michigan, is located on the South¬ern shore of the Upper Peninsula on a sheltered area of Lake Michigan called Little Bay de Noquet. The Chicago and North Western Transportation Company has operated a rail-to-ship ore transfer facility at this location for well over 100-years. It is the only terminal of its type on Take Michigan and thus can offer a longer navigation season to lower lake markets than other upper lake ports. It all started in 1864 when the Peninsula Railroad of Michigan, now a part of the C&NW, completed a 100 km rail line from Little Bay de Noquet to the Jackson Mines at Negnauee, Michigan. During that first year of operation approximately 31 000t of ore were loaded onto ships at Escanaba from what was then called the Merchants Dock. By 1871 demand had already exceeded capacity and it was necessary to build a larger dock, which in turn was replaced with a still larger pocket dock in 1903. There are no plans or records available to indicate how the ore was handled from rail to ship prior to the construction of the pocket dock.

Jan 1, 1981

By Peter J. Szabo

In 1980, a caravan of representatives of Japanese trading companies debarked on the shores of the United States bearing gifts of watches, electronic games, and radios. In early 1983, we find in a parking lot of a major U.S. coal company, a haggard general manager of marketing returning to the Orient with a box under his arm of trinkets of his own; cross pens with company logos, alarm clocks, etc. The tables have turned, but our fellow sitting in a jet plane over the Pacific Ocean had only to heed the warning of the famous 19th Century poet well familiar with the ways of the Far East. Kipling said; "And the End of the Fight is a tombstone white and with the name of the late deceased, And the epitaph drear, a fool lies here who tried to hustle the East."

Jan 1, 1984

By Heinz C. Dittmar

The phenomenon of radioactivity has been known since the turn of the last century. Scientists of many nations, intrigued by the strange effects of radioactivity, have engaged in research to probe the heretofore presumed, but largely unknown world of atomic structures and subatomic- particles. A theory evolved of splitting the atom, thus providing insight into the structure of matter and opening the way to possibly create new materials. Many years of effort culminated in the first chain reaction in 1942. The beginning of the atomic age was drastically demonstrated by the flash of the large scale chain reaction of the first atom bomb. It was actual proof of the incredible energies contained in matter.

Jan 1, 1966

By C. W. Overton

The operations of Bethlehem Copper are situated in the south-central interior of British Colombia at an elevation of 4900 feet above sea level. Main road and rail transportation systems pass through Ashcroft in the Thompson Valley, which is 28 miles by road from the minesite. The operation was the first low-grade open-pit porphyry copper mine in British Colombia. The minerals are chiefly chalcopyrite and bornite, while the rock is principally feldspar and quartz. In the outer fringes of the orebodies sane pyrite is present. Average grade of mill feed is 0.55% copper.

Jan 1, 1973

By Raymond L. Jones

With the inauguration of the open pit operation in Bagdad, plans were formulated for a large scale leaching operation. Dump stockpiling was started almost immediately, but actual production was not initiated until the spring of 1961. Like all neophytes, we started something about which, on a commercial scale, we knew next to nothing, either dump preparation or leach procedure, and as a consequence, we are still paying the piper. True, we had been through an extensive laboratory pilot program, but it soon became apparent that there was considerably more to increasing solution volumes than simple multiplication. Had we initially possessed our present acumen, the Cyprus Bagdad plant could be operated more efficiently and at a better profit. During the past several years, the art of dump leaching of copper has improved in many ways, primarily because of the application of scientific principles gleaned from general mining practice. Rigid pH control and the use of atomic absorption techniques for rapid," accurate assaying have probably played a leading role in this respect, although we cannot overlook the other sophisticated electronic controls lending improvement to acid addition and pumping, better piping materials, and lastly, the more efficient use of our pregnant liquors. Thin too, the years of experience have given us a greater understanding of dump behavior in general; and, we can, to a greater extent, measure, predict, and avoid some of the idiosyncrasies inherent in every dump. However, it is my firm belief that we will still be confronted with unexplainable dump behavior as long as we are involved in leaching. We have found our dump to be a wonderful money bank, but one that is capable of yielding a wildly fluctuating profit.

Jan 1, 1975

By Xinzhi (Thomas) Du

"A longwall mining method is a productive mining method of coal extraction that involves the complete removal of large, rectangular panels of coal. Since this method causes deformations through the overlying strata to the ground surface, the surface- and ground-water regime above the longwall panels may be adversely affected and drained into the lower strata. The purpose of this study is to determine the effects of longwall mining subsidence on surface- and ground-water systems.This study is a site-specific hydrogeologic analysis conducted before, during, and after panel retreat at a site located over two selected longwall panels in the Pittsburgh coal seam in Greene County of Pennsylvania. Mine subsidence causes fractures in the overlying strata and enlarges bedding plane separations, increasing the effective porosity and storativity of the overlying strata. Generally, the water in deeper aquifers located in the lower fractured zone drains into the mine void due to the vertical fractures. Moreover, the water level does not recover after longwall mining (but may recover when the mine is flooded). The upper aquifers over the thick aquitard layers may maintain the water level or drop slightly during longwall mining and recover very quickly. The reason is that the underlying aquiclude layer has less change in porosity and permeability after longwall mining (Carver, 1994).A groundwater flow model-MODFLOW was used to predict the water table contours for the periods of pre- and post-mining conditions. The hydraulic gradients of post-subsidence became larger outside the panels and smaller inside the panels than that of the pre-subsidence. The groundwater hydraulic heads above the longwall panel dropped a maximum 50 ft in the study panels. The shallows monitoring wells that were less than 50 ft deep from the surface were deeply affected by longwall mining subsidence. For the intermediate wells that were more than 85 ft deep from the surface, where strata movement acted as a unit during longwall mining subsidence, there were little impacts of longwall mining on the intermediate wells in the study area. For the deep wells that were located below the Waynesburg sandstone, the water was drained to the underlying strata or even into the mine gob."

Jan 1, 2019

By Harold Bloom

Dimethylglyoxime reacts with nickel in a buffered ammonical-citrate solution containing the detergent ?Aquet? and hyroxylamine-hydrochloride. The resulting nickelous dimethylglyoxime is extracted with xylene. Visual comparison with standards permits the estimation of from 50 to 10,000 ppm of nickel. Soil, rock, or sediment may be decomposed by digestion with (1-3) nitric acid, allowing about 70 determinations per man-day to be carried out. With minor modifications to the above procedure, sediment and soil may be semi-quantitatively analyzed for nickel at the sample site. The chemical equipment is easily portable and the analysis extremely rapid because the buffer, dime thylglyoxime and xylene are added simultaneously to the sample and no heating is required. The sensitivity varies with the "availability" of the nickel ions; under favorable conditions, one may obtain a positive test for as little as 10 micrograms in soils and sediments. This procedure is similar to one, for the field determination of heavy metals described elsewhere by the author.

Jan 1, 1958

By A. D. Davis

The disposal of spent ore from cyanide heap-leach processing facilities is of concern to the mining industry, regulatory agencies, and the public. Disposal of several hundred million tons of additional spent ore is planned in the western United States during the next decade, with increased amounts likely if gold prices rise. In the past decade, more than fifteen million tons of spent ore have been disposed of in the Black Hills. South Dakota's off-loading criterion for cyanide has been set by the state's Department of Environment and Natural Resources at 0.5 parts per million (ppm) as weak acid dissociable (WAD) cyanide. Nitrate off-loading limits vary for each mine in the state, depending on ore type and other factors. Nitrate concentrations in leachate from spent ore depositories could be caused by conversion from other nitrogen-containing species. One likely source of nitrate is residual explosives from blasting of ore. Previous work on the combustion products of nitrogen explosives has shown incomplete 3xidation (Johansson and Persson, 1970). Another likely nitrate source is degradation of cyanide to ammonia, followed by oxidation to nitrite and nitrate.

Jan 1, 1994

The Sage Mill Project w approved by Santa Fe Pacific Gold Corporation's Board of Directors in October 1994. The Sage Mill Project included a pressure oxidation plant designed and constructed to process refractory carbonaceous ore using fine grinding/autoclaving technology developed specifically to treat Twin Creeks ore. The project was constructed in two phases. The first phase was put into operation on May 5, 1997, just hours before the transfer of ownership to Newmont Gold Company occurred. The second phase started in October 1997. This paper reviews schedule, costs, scope changes, and methodology used on the project that spanned almost five years from project definition through commercial operation.

Jan 1, 1999

By K. Bommer

"In today’s fast paced, globally competitive world, reliability and machine uptime are of the utmost importance to a successful operation. Along with these targets more emphasis is being put on cost reduction and decreasing the environmental impact of the overall system. To achieve these goals, automatic lubricators and lubrication systems have been used in many industries for years and are now becoming a common tool in the mining industry as well. These systems are able to provide proper lubrication amounts at the proper times autonomously, helping to keep the machines running smoothly while minimizing the physical support required. Copper mines in the southwest have begun utilizing auto lubrication to avoid mistakes and unplanned shut downs on critical equipment. This paper will describe the engineering behind these products and review case histories where these tools have been successfully utilized in the mining industry. INTRODUCTION In a dirty, dusty, wet environment, where machine uptime is imperative, proper lubrication of bearings is the only way to survive. With the push for cost reduction and mines striving to lower their environmental impact and increase worker safety according to MSHA guidelines, the old lubrication practices have come under scrutiny. It is no longer encouraged or cost effective to have maintenance personal walk from point to point throughout the entire mine pumping a shot of grease into each bearing once per shift. Automatic lubricators and lubrication systems have been on the market for years but recently, as the market focus has changed and technology has developed, the use of these systems has begun to rise in the mining industry. Automatic lubrication systems can be as simple as a single point lubricator lubricating one (1) bearing or a more complex system lubricating numerous bearings. With system design, the automatic lubricator provides a preset amount of grease to a bearing at regular, predetermined intervals. The systems designed to lubricate more than one bearing contain grease pumps of some design and possibly PLC controllers which can be used to remotely adjust and monitor the system. As can be seen in Figure 1, the right amount of lubrication can be achieved much more reliably with automatic lubricators. Depending on application needs, the market now has products to fit almost every wish list. This paper is going to focus on the single point systems that are lower in cost but are still being effective."

Jan 1, 2015

By Donald M. Duncan

An acceptable source of concrete aggregate is available in Kansas City in a continuous, medium bedded, slightly dipping limestone unit. Removal is accomplished in shallow depth, 12 feet to 17 feet high, room and pillar mines. The accepted empirical design spaces 20 foot pillars 60 feet on center. A portion of the 20 foot unit is left in place for roof support. Rock and soil cover is variable to 100± feet maximum. Long-term stability of these mines is affected by numerous factors, including the above mine-rock profile, ground water conditions and mining practice. Crusher-run aggregate sells at the mine for $2.20 per ton, yielding a gross income of $2.00 to $2.80 per square foot of mine. Use of mine space for real estate development requires a new perspective in mine development. Mining practices to obtain long term stabile structures can become an over-riding factor as compared with minimum production costs and maximum extraction ratios. Poorly mined areas are unusuable for secondary purposes. Development cost for lease space in less desirable mines is substantially greater than those planned for a secondary use. Real estate development in mine space involves unique engineering problems. Properly engineered developments offer singular advantages. Warehouse lease space sells for $.50 to $1.00 per square foot per year; fully developed office areas may double these values.

Jan 1, 1968