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By C. A. Winkler, V. Hospadaruk

PREVIOUS papers from this laboratory have discussed the effect of chloride ion on the cathode polarization during electrodeposition of copper from copper sulphate-sulphuric acid electrolytes, in the presence and absence of gelatin. The steady state polarization'" was found to decrease sharply and pass through a minimum with increasing chloride ion concentration in the presence of gelatin. The minimum shifted to higher chloride ion concentrations and to higher polarization values with increase in current density or gelatin concentration, while an increase of temperature shifted the minimum toward lower halide concentrations and lower polarizations. Since these observations were made in acid-copper sulphate electrolytes that contained no other addend than gelatin, there was obviously the possibility that they were not applicable to deposition of copper from commercial electrolytes that contain a variety of other substances in relatively small amounts. In particular, it was of interest to determine whether the presence of arsenic, antimony, or bismuth in the electrolyte would materially alter the behavior. Experiments have now been made under a variety of conditions with systems containing these cations, and the results are summarized in the present paper. Experimental Polarization measurements were made at 24.5oC in a Haring cell in the manner described previously.' Electrolytes were made with doubly-distilled water, and contained 125 g per liter of copper sulphate and 100 g per liter sulphuric acid, both of reagent grade Eimer and Amend gelatin from a single stock was used throughout. Chloride ion was introduced as reagent grade sodium chloride, and arsenic, antimony, and bismuth by dissolving the chemically pure metal in hot concentrated sulphuric acid and adding appropriate amounts of the solutions to the electrolyte. Each cathode, of 1/16-in. thick rolled copper, was first etched in 40 pct nitric acid and washed thoroughly with distilled water. The surface was then brought to a standard condition4~9 by electrodeposition from an acid-copper sulphate electrolyte containing no gelatin, at a current density of 3 amp per sq dm for 30 min, followed by deposition at a current density of 2 amp per sq dm for l hr. As in previous studies, the cathode polarization eventually attained a steady-state value (15 to 75 min) such that further change in polarization did not exceed 0.2 mv per min. The polarization values recorded are those for the steady states. "Excess weights" were determined with arsenic and antimony present in the electrolyte, as the difference between the weights of the deposits obtained in the presence of these cations and those obtained in their absence, with the two cells connected in series. When gelatin was present along with the arsenic or antimony, it was also added to the electrolyte in the cell in series. Results and Discussion The results of the study are summarized in Figs. 1 to 6. From Fig. 1, top, it is evident that the presence of arsenic or antimony alone results in an increase of polarization, while bismuth alone causes a decrease. The presence of gelatin (25 mg per liter) rather drastically modifies all three cation effects, as indicated in the lower panels of the same figure. The addition of chloride ion, when no gelatin is present, causes comparable decreases in polarization in the presence of antimony and bismuth, but a relatively larger decrease when the electrolyte contains arsenic. It is interesting to note that the decrease in polarization brought about by addition of chloride when both arsenic and antimony are present parallels the behavior with arsenic alone, while the polarization in the electrolyte containing the cation mixture, without chloride added, corresponds to that for an electrolyte containing only the antimony cation. Similarly, the polarization at zero concentration of chloride in electrolyte containing arsenic and bismuth is that corresponding to an electrolyte containing arsenic alone. From Figs. 3a, 4a and 4b, it is clear that, in the presence of gelatin at a level of 25 mg per liter, the effect of chloride in the presence of arsenic and antimony, or a mixture of the two, becomes quite analogous to that observed in the absence of added cations. When both bismuth and gelatin are present (Fig. 5), the decrease in polarization with increased chloride concentration is virtually absent. This is perhaps a reflection of the large decrease in polarization brought about by the bismuth itself in the presence of gelatin. The shifts of the minimum in the polarization-chloride concentration curves brought about by changes of temperature (Fig. 3b), gelatin concentration (Figs. 3c and 4c) and current density (Fig. 3d) when the metal cations were present are all similar to the corresponding shifts observed in their absence." The approximately linear "excess weightv-anti-mony concentration relation recorded in Fig. 6 would seem to indicate that antimony is codeposited with copper to a considerable extent. On the other hand, only very limited amounts of arsenic appear to be adsorbed or codeposited.

Jan 1, 1954

By D. A. Whitley, R. P. Carone

"Shaft sinking by blind shaft drilling offers the mining industry a different approach to shaft construction. Benefits of blind drilling include less construction time and fewer safety problems while being economically competitive with conventional sinking methods under certain conditions in soft water-bearing formations.Technology and equipment are available today to drill blind shafts up to 20 feet in diameter and over 3,000 feet deep. This is an extension of proven techniques developed by private industry. To drill a 20-foot-diameter hole requires a specially manufactured hydraulic drill unit with a rated hoist of 2 million pounds and 500,000 ft/lb of torque.This brief paper will discuss the following aspects of blind shaft drilling:• benefits;• equipment f or drilling;• circulation methods;• circulation rates;• shaft alignment; and• progress rates to be expected.IntroductionShaft sinking by blind shaft drilling offers the mining industry an improved alternative method for shaft construction. The drilling of 20-foot -diameter shafts to depth s in excess of 3,000 feet can be done by utilizing equipment specifically designed and manufactured for this purpose. This equipment is a distant cousin, at best, to standard oil well drilling rigs. The actual configuration of these drilling machines will be discussed in a following section.To most people, the drilling of mine shafts may seem to be a new or at least recent technology. However, as early as the I920s, German and Dutch miners were drilling 24-foot diameter shafts for coal mines. What led ""miners to resort to drilling were ground conditions that still plague conventional shaft sinkers today: soft , water-bearing formations. The major drawback to these early attempts was a low penetration rate due to poor bit cleaning. This, however, was not the end of early shaft drilling activity. From 1936 to 1950, a number of mine shafts were drilled by the calyx or coring method. This method employs a bit with a large bore down the center. As it drills, it cuts a core. When 5 to 10 feet have been drilled, the core is removed. The disadvantages of this method were the time and work involved in breaking the core free, and it was inadequate in soft water-bearing ground."

Jan 1, 1981

Upon the recommendation of its Technical Committee, The Com-pressed Air Society has adopted the following definitions of, certain terms. Displacement.-The displacement of an air compressor is the volume displaced by the net area of the compressor piston. Capacity.-The capacity should be expressed in cubic feet per minute, and is the actual amount of air compressed and delivered, expressed in terms of free air at intake temperature and at the pressure of dry air at the suction. Volumetric Efficiency.-Volumetric efficiency is the ratio of the capacity to the displacement of the compressor, all as defined above. Compression Efficiency.-Compression efficiency is the ratio of the work required to compress isothermally all the air delivered by an air compressor to the work actually clone within the compressor cylinder, as shown by indicator cards, and may he expressed is the product of the volumetric efficiency (the intake pressure and the hyperbolic logarithm of the ratio of compression), all divided by the indicated mean effective pressure within the air cylinder or cylinders.

Jan 8, 1918

Jan 1, 1930

By H. Shafick Hanna

The major problems are identified the high phosphorus content and the fine dissemination or encapsulation of mineral impurities, in, ,the iron bearing minerals, A process which combined extreme fine grinding techniques with magnetizing roasting or flotation separation methods, is suggested. By these methods concentrates assaying 60-61 percent Fe exceeding the widely accepted upper limit of 56 percent Fe set for these ores, were produced with 75-90 percent iron recovery. Moreover it was shown that the phosphorus content of these concentrates could be reduced from 0.25 to 0.03 percent phosphorus by acid leaching. A brief discussion on production costs based on current and future developments in iron ore processing is given.

Jan 1, 1980

By Herman W. Sheffer

This report describes and discusses present-day leaching technology employed to recover copper from low-grade mine and dump materials derived from the exploitation of copper ore deposits in the Western United States. Illustrations of the integral parts of the leaching, precipitation, and recovery operations at several copper-producing companies are presented. Schematic drawings are included to present typical flowsheets of leaching and precipitation operations. Operational problems common to most copper leaching and precipitation plants are discussed. Areas of present and future research to improve leaching techniques are cited.

Jan 1, 1968

By B. Ladanyi

An adequate knowledge of the overall behavior of a rock mass at a given site is fundamental to the satisfactory design of a rock slope. The be- havior is controlled by a variety of factors, in- cluding rock type, geological structure, stress and ground water conditions. There are essentially three lines of approach that may be used to obtain information on the in-situ rock mass behavior for the purpose of the design of a rock slope: (1) Direct measurements of rock mass properties by means ol laboratory and field tests. (2) Evaluation of rock mass properties from a study of slope failure case histories and sta- tistical information on stable and unstable natural rock slopes. (3) Evaluation of in-situ behavior of rock mass by using a physical or mathematical model technique.

Jan 1, 1980

By Carl L. Bieniewski

U.S. molybdenum production increased fivefold from 18.2 million pounds in 1946 to 90.5 million pounds in 1966, and constituted 87.3 percent of the total free world supply in the 1946-66 period. Mining development in other free world countries in the next few years may reduce the magnitude of the U.S. position, although similar development planned for the United States may counteract some of the relative gains by those countries. In 1966 two-thirds of the reported molybdenum consumption in the United States by end uses was as an alloying element in steel. Molybdenum also has important use as an alloying element in iron and high-temperature alloys. Consumption of molybdenum metal for making fabricated parts has increased in the past few years, especially in the space and nuclear industries. Molybdenum compounds are used mainly for making pigment, catalysts, and lubricants. Based on producer reports of shipments of primary products to domestic customers, U.S. consumption of molybdenum increased from 16.5 million pounds of molybdenum in 1946 to 65.6 million pounds in 1966. U.S. molybdenum reserves are now estimated to be 5.9 billion pounds of recoverable molybdenum, an increase of 2.1 billion pounds above previous estimates. Molybdenum ores account for 71.4 percent of the reserves, copper ores for 22.3 percent and copper-molybdenum, tungsten, and uranium ores for 6.3 percent. Several methods for predicting future demand are illustrated and estimates of demand using these methods were made for 1975. Based on present capacities and announced company plans for future developments, estimates of annual production were made for 1967 through 1975 for the United States, Canada. Chile, Peru, and the free world. These data indicate that molybdenum production in 1975 for the free world is expected to be 246 million pounds with the United States producing 68.2 percent and Canada, Chile, and Peru 30.3 percent.

Jan 1, 1970

By J. P. McCluskey

The effects of air quality regulations passed in the last few years have been felt in a more pervasive way by the electric utility industry than by perhaps any other industry. I'm referring especially to those regulations dealing with the control of air emissions from stationary sources, and those specifying the quality of fuel used. Particularly, I would like to describe some of the effects that these regulations have had on the Commonwealth Edison Company. To put the subject into perspective, a brief descrip¬tion of the company will be presented first. Then, a historical outline of some of the efforts at control of electric generating station emissions will be described. Following this will be an indication of the Company's response to early State and local regulations prompted by the growing pressure for stringent envi¬ronmental control. Finally, the Company's plans to achieve com¬pliance with the most recent, Federally approved, State of Illinois regulations will be summarized.

Jan 1, 1973

By James A. L. White

Although the quantity of native sulphur associated with volcanism is large, production from such deposits represents only a very small percentage of total world production, This paper describes the location of the known deposits, the typical geology of these deposits and the nature of the sulphur mineralization. Methods of treatment are discussed and some comments are offered on the economic position of these occurences in world sulphur markets.

Jan 1, 1967

By M. A. A. de Klaver

Functional Description Figure 1 is a typical flowsheet for a system for solid fuel addition to filter cake. Solid fuel, coal, coal breeze, or charcoal, is fed from a,stockpile to a surge hopper. The solid fuel is metered into a grinding mill. The fuel is dried and ground in a grinding mill. The on-size particles are removed from the mill by air sweeping. The ground solid fuel is separated from the air stream by a cyclone and stored in a surge hopper. The ground solid fuel is then pneumatically conveyed to a small hopper in the balling area. The fuel is proportioned into the filter cake just prior to mixing. An efficient mixer is very important to have a successful operation. The exact flowsheet would depend on a number of factors including what fuel is used, how the fuel is received, and the cnaracteristics of the fuel as received. Availability of floor space in the plant may also affect the flowsheet. For example, drying air may be supplied from the pellet furnace if the grinding mill can be located near the grate, or the pneumatic conveying system and a surge hopper may be eliminated by placing the grinding mill adjacent .to the mixing area. Also, for a multiple line plant, a ball mill rather than a roller mill may be more suitable.

Jan 1, 1980

By Wendell R. Peters

Shallow underground voids resulting from early coal mining and other resource recovery activities over the past several decades are now being recognized as a significant cause of ground subsidence problems in developing urban areas. Uncertain knowledge of abandoned coal mines also imposes potential hazards in coal excavation operations since water inundation or the release of methane gas is a pricnipal hazard when mine excavation operations break into an abandoned mine. U.S. Army requirements for an effective method for detecting and mapping subversive man-made tunnels have resulted in a surface-operated automatic earth resistivity survey system with a digital computer data processing system. Field tests aimed at demonstrating the system performance resulted in successful detection of tunnels having depth-to-diameter ratios up to 15 to 1. Under the sponsorship of the Bureau of Mines, a similar system was designed and constructed for use in the detection of coal mine workings. This report discusses the hardware and software aspects of the system and the application of the high-resolution earth resistivity method to the survey and mapping of abandoned coal mine workings. In the field tests reported, the targets of interest were both air-filled and water-filled workings.

Jan 1, 1980

By B. G. Hicks

The Manapouri Power Project is located in New Zealand's South Island Fiordland. The project is being constructed for the New Zealand Ministry of Works. Construction began in 1963 and is scheduled' for completion in 1969. The project will divert water from the natural, glacially carved Lake Manapouri, at Elevation 580, through vertical- penstocks into an underground powerhouse 364 feet long, 127 feet high, and 59 feet wide excavated about 700 feet below ground surface and about 560 feet below the present lake level. The possible ultimate power installation will produce 700 megawatts from turbines located in the underground machine hall. The turbine flow will discharge through the 6-mile, 30-foot diameter tailrace tunnel into a fiord arm of the Tasman Sea. The rocks in the project area are primarily Paleozoic Fiordland Complex gneiss, schist, amphibolite, and marble intruded by granitic rocks and pegmatite. Shear zones have been encountered in the tunnels and machine hall. These produce water and occasionally require steel support. The machine hall arch was stabilized entirely by rock bolt reinforcement. Rock mechanics instrumentation has been used throughout the project both for pre-construction design calculations and to monitor tunnel rock loads and movements of the machine hall roof and walls. About 28 miles of the 100-mile transmission line will be constructed across glacially oversteepened slopes and debris or swamp filled valleys between the power plant and the eastern edge of the mountainous area. Steep glacially carved rock slopes and locally unstable glacial till complicated construction of the transmission line access roads.

Jan 1, 1968

By Fred A. Curtis, Kathryn E. Moore

"The past 14 years have brought an increased awareness of environmental problems. Surface mining for mineral aggregates has been one o f the issues which ha s sparked fierce controversy and debate. Various level s of government, industry, and the public have engaged in an unending battle for adequate planning, regulation, and rehabilitation of pits and quarries. Agreement has seldom been reached and, as a result, few standards, guidelines or policies have been established, or enforced province-wide.Surface mining ca uses a number of environmental problems including noise, dust, water table disturbances, aesthetic degradation, increased traffic, and health and safety hazards. These problems are particularly serious in urbanizing area s, where people are exposed to the mining operations. Associated with the operational phase of surface mining are the issues generated by the multiplicity of abandoned pits and quarries which dot the countryside. These large, gaping, often dangerous waterfilled holes are a blight o n the landscape, and represent a misuse of land.The environmental problems connected with pit s and quarries are compounded by the fact that accessible reserves of mineral aggregates are being lost through the process o f urbanization. In addition, restrictive zoning at the municipal level is restricting access to even more aggregate rich land. This results in the paradox that the very urbanizing process which creates the demand for aggregates is rapidly reducing the available supply. These problems have stimulated the Ontario Ministry of Natural Resources to call for a province-wide program of inventory, assessment and planning for the protection o f high-quality reserves in Official Plans. These proposals have met with strong opposition from municipal leaders, who are jealously protecting their autonomy.Environmental management education is a prerequisite for all parties involved in pit and quarry planning, regulation or rehabilitation. To this end the following bibliography of selected articles with attention given to the Ontario experience, should provide helpful information on these topics."

Jan 1, 1985

By Desmond M. Levins

"Australia has almost twenty per cent of the Western World's low-cost uranium reserves, located mostly in the Alligator Rivers region of the Northern Territory. At present, only one uranium mill is operating in Australia, but a number of new mills are planned for the early 1980s.Details are given of Australian uranium mining and milling proposals and the measures taken to minimize their environmental impact. Major factors affecting environmental impact are discussed, including treatment of liquid wastes, water management, control of radon and other airborne releases, and disposal of tailings. IntroductionAustralia is entering a new phase in uranium mining and milling activity . In the first phase of operations, between 1954 and 1971, about 10,000 tonnes of yellowcake was produced at five locations. Most of the production came from the mines at Rum Jungle in the Northern Territory and Mary Kathleen in Queensland. In the 1960s, the demand for uranium slumped, and much of the yellowcake produced at Rum Jungle was stockpiled by the Australian Atomic Energy Commission. The early uranium processing operations in Australia were typical of overseas practice at that time. Environmental problems were generally given low priority and pollution control measures were unacceptable by today's standards. There was little or no recycling of process water, acid waste streams were not neutralized and tailings dams were poorly designed. At Rum Jungle, oxidation of sulphides in waste heaps, tailings dumps and ore stockpiles subsequently led to destruction of vegetation and heavy metal pollution in a nearby river.In the early 1970s, major uranium deposits were discovered in the Alligator Rivers region of the Northern Territory. Significant orebodies were also located in the Great Artesian Basin in South Australia, in calcrete formations in Western Australia and at several locations in Northern Queensland. According to latest available estimates. Australia has about 160/0 of the Western World's uranium recoverable below $US 80 per kg U. Mining these orebodies will require pollution control measures more stringent than practised previously in Australia."

Jan 1, 1980

By D. W. H. Su

"This paper presents the results of a comprehensive study conducted by CONSOL Energy, Marcellus Shale Coalition, and Pennsylvania Coal Association to evaluate the effects of longwall-induced subsurface deformations on the mechanical integrity of shale gas wells drilled over a longwall abutment pillar. The primary objective is to demonstrate that a properly constructed gas well in a standard longwall abutment pillar can maintain mechanical integrity during and after mining operations. A study site was selected over a southwestern Pennsylvania coal mine, which extracts 1,500-ft-wide longwall faces under about 600 feet of cover. Four test wells and four monitoring wells were drilled and installed over a 125-ft by 275-ft centers abutment pillar. In addition to the test wells and monitoring wells, surface subsidence measurements and underground coal pillar pressure measurements were conducted as the 1,500-ft-wide longwall panels on the south and north sides of the abutment pillar were mined by. To evaluate the resulting coal protection casing profile and lateral displacement, three separate 60-arm caliper surveys were conducted. Prior to the longwall panels being mined by, a number of 3D finite element simulations were conducted to estimate subsidence at the surface, coal pillar pressure increases, the resulting coal protection casing profile and displacement, and the vertical and horizontal displacements in the four monitoring wells. Comparisons of the pre-mining 3D finite element simulation results and the surface/subsurface/underground instrumentation results show that the measured test well and IPI casing deformations and profiles are in reasonable agreement with those predicted by the 3D finite element models, and that the measured surface subsidence and pillar pressure are in excellent agreement with those predicted by the 3D models, which serves to validate the 3D finite element models. Parametric studies employing the validated 3D finite element models demonstrate that larger coal protection casing thickness is expected to have little effect on the lateral deformation, although it may reduce the magnitude of casing plastic deformation, and under deeper cover (~1,100 feet), lateral casing deformation is expected to be smaller, although larger plastic casing deformation may be present near the seam level. Also, evaluation of various casing and cementing designs using the validated 3D models clearly indicates that, when all casings are grouted to the surface except the intermediate and production casings, the intermediate and production casings show little deformation and no plastic strain. This research represents a very important step and initiative to utilize the knowledge and science obtained from mining research to improve miner and public safety as well as the safety and health of the oil and gas industries"

Jan 1, 2017

By C. O. Riggs

Geotechnical exploration in North America, in particular, exploration for deep foundations analyses, is currently and generally performed following the most basic sampling and insitu testing methods and techniques. Some would surely say that the state-of-practice severely lags the state-of-the-art. Probably more than 90% of all deep foundations, both driven piles and drilled piers, installed in North America are initially analyzed and designed, i. e. geotechnically, on the basis of either the soil penetration resistance obtained by performing the "Standard Penetration Test" (SPT), or from laboratory shear tests performed on samples obtained using 76-mm (3-in.) nominal diameter, thin wall, "Shelby tube" samplers. The use of design data obtained with other exploration methods and devices, such as bore hole pressure meters, flat plate dilatometers, even cone penetrometers, occur on the fringes of practice and often in conjunction with the use of the two simpler methods of analysis. This basic approach probably represents an attempt of the profession to use, as much as possible, common, easily understood and easily communicated procedures in all geologic environments. The characteristics of drill rigs with the required drilling and samplng tools vary somewhat from region to region in North America according to the physiography of the area of use, the types of exploration data required on a day-to-day basis, the philosophy of the engineers and geologists that use the exploration data and the financial resources of the drill rig owner. The physical capability of the exploration drill rig used on a project can have a significant effect on the quality of samples or insitu tests. The physical configuration and the quality of the drill and the drilling, sampling and testing tools not only provide the mechanical capability to obtain data but affect the attitude of the field exploration crew and the quality of work. This complete presentation is taken, for the most part, from a book in preparation for publication: "Geotechnical Exploration and Site Characterization" by C. Riggs, A. Hatheway and N. Schmidt. The book is scheduled for completion during 1987.

Jan 1, 2010

By Henry Rawdon

THE structure of wrought iron as usually described by metallographists and workers in metal in general is that of a fairly pure iron. Impurities, if present, are usually considered as being in solid solution in the crystals of the ferrite matrix or as forming part of the ever present "slag streaks." Attention is herein directed to one type of these dissolved impurities; to the detection of such impurities, particularly in low-grade irons, and to their possible influence on the physical properties of the metal. The attention of the Bureau of Standards was first directed to wrought iron of the peculiar and unusual characteristics to be described later, in material which had failed in service and was submitted for test. The examination was extended to other grades of wrought iron, to see whether such features are of common occurrence in this class of material. MICROSTRUCTURE OF WROUGHT IRON Usual Structure The general microstructure of wrought iron is so well known that a detailed description of it here is needless. There is shown in Fig. 2 the structure of a sample of Swedish iron which illustrates well the matrix of ferrite crystals in which are embedded the slag threads so characteristic of the puddling process and the subsequent working of the material. The usual commercial product contains varying amounts of the impurities commonly associated with iron and steel, i.e., manganese, phosphorus, silicon, and sulphur together with small amounts of carbon. Of these, the larger part of the phosphorus and some of the silicon present are held in solid solution in the ferrite while most of the remaining impurities, other than carbon, exist in the inclosures of slag. Aside from the discontinuities introduced by the slag streaks the ferrite matrix has the microstructure and appearance of a pure metal. No definite orientation of the various crystals or grains is apparent; deep etching of the specimens reveals no intracrystalline features (i.e., within the grains) other than those noted in "pure" metals in general (etching pits).

Jan 9, 1917

By H. Stocker, C. E. Makepeace

"This paper presents the statistical analyses of several sets of data acquired in several programs of sampling of radon daughters in uranium mines. The measurements were taken over periods of days or weeks for given locations or location occupations within these mines. Because the sampling applies to specific intervals of time and specific locations, a method is suggested f or the eventual application of a monitoring program which would be suitable on an annual basis for these locations. The present data and analyses thereof are not justifiably applicable to a monitoring regimen on an annualbasis, without a number of additional assumptions.The aim of the present analyses of concentration measurements is the determination of the minimum number of measurements required to achieve an annual radon daughter exposure estimate, for individual workers, having an error no greater than 50% at the 95% confidence level. The criterion of accuracy is taken from a statement in the American National Standard, Radiation Protection in Uranium Mines (ANSI NI3.8-I973), and is currently used, in somewhat modified form, as a guide to uranium mining licensees in Canada. Uncertainties associated with occupancy time are ignored in the present analysis. IntroductionOne of the principal aims of any scheme of radiation protection is that of improving the accuracy of exposure estimation for workers. The example presented here is from the area of radon daughter exposure estimation for uranium miners. The conventional means of estimating workers' exposures is grab sampling of radon daughter concentrations combined with occupancy time weighting in the various work and travel locations. Uncertainties exist in each of these components, and in an environment of highly variable radon daughter concentrations (such as an active uranium mine) one is always uncertain as to the representativeness of the grab sample (compared to the average concentration) unless a sophisticated monitoring scheme has been implemented based on previous experience in such an environment.Improvements in the accuracy and precision of employee radon daughter exposure records depend, primarily, on three factors;"

Jan 1, 1980

The Kelian gold mine which was developed in East Kalimantan Indonesia in 1990 - 1992 is scheduled to complete mining and processing operations in 2004. This will have a major impact on the neighbouring communities who have benefited from the jobs, economic activity and infrastructure development which has been generated by the mine. Currently, there are no formal regulations or standards specifying the procedures for relinquishment of mining leases in Indonesia. Furthermore, a move towards regional autonomy, providing greater authority and responsibility to local (regional) areas, has recently been implemented in Indonesia and limited capacity exists in the new regional governments. Consequently, in October 2000, Kelian Equatorial Mining (KEM) initiated a partnership with the local community and government to explore sustainable post-closure options for the mine site and community development programs. The Kelian mine closure strategy seeks full involvement of all stakeholders through the Kelian Mine Closure Steering Committee (MCSC) in the development of sustainable solutions which will enable communities to secure long-term benefits and minimise post-closure risks from the KEM operations. This organisation, jointly chaired by the Head (Bupati) of the regional West Kutai government and the KEM President Director, with representatives from the local communities, governments and NGOs, has developed a Charter, a website and evaluation criteria to ensure accountability and transparency. There are four technical working groups, consisting of representatives from the mine, local community leaders, NGOs, Universities, Local, Provincial and Central Government Departments, which report to the Steering Committee. These working groups have researched, developed and recommended sustainable options to the Steering Committee. The MCSC has met quarterly to examine options in accordance with the criteria set out in the Charter and has endorsed sustainable solutions which have support from Government, Community and the mine. This paper describes the closure risks, sustainable outcomes derived through the Kelian mine closure steering committee process and outlines the methodologies used to develop and endorse sustainable solutions in a society with limited capacity undergoing enormous change and uncertainty.

Jan 1, 2003