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By William A. Vogely, Lawrence J. MacDonnell

This section begins with an introduction to several key environmental laws. This is followed by a discussion of some of the issues raised by such environmental regulation. Finally the subject of regulatory reform is addressed. Overview of Selected Major Environmental Laws The number, type and complexity of environmental laws and regulations affecting mineral resources development have grown at an astonishing rate since the 1960s. The most significant laws and regulations are those addressing the use of the public lands; those concerned with air quality, water quality, and surface reclamation; and those defining government responsibility for its actions having important environmental consequences. The laws and regulations governing activities on the public lands will be taken up in the section 5.15C, "Minerals and Land Management." In this section we will concentrate on five primary laws: the Clean Air Act, the Clean Water Act, the Surface Mining Control and Reclamation Act, the Endangered Species Act, and the National Environmental Policy Act. The Clean Air Act: The legislative and regulatory framework for controlling air pollution has developed in a series of steps. Most important for present purposes are the Clean Air Act of 1970 (P.L. 9 1-604) and the 1977 Amendments (P.L. 95-95). The rather complex air quality control scheme includes four key elements-national ambient air quality standards, state implementation plans, the prevention of significant deterioration program, and the non- attainment program. National Air Quality Standards. The 1970 Clean Air Act is a landmark law because it contains the first explicit recognition that pollution is a nationwide problem requiring a national control program. The federal government through the Environmental Protection Agency (EPA) was to establish national air quality standards for at least the six pollutants named in the Act (sulfur dioxide, carbon monoxide, total suspended particulates, photochemical oxidants, hydrocarbons, and nitrogen dioxide). These standards were to be established so as to protect public health, "allowing an adequate margin of safety." The cost of achieving these standards is not to be considered. The 1970 Act unrealistically required that these standards be achieved in all areas of the country by 1975. As the program has developed, the air quality control regions are now to be designated as "attainment" or "nonattainment" with respect to each of the national standards. State Implementation Plans. Under the Act the states are given the primary role in achieving the ambient standards. States are to develop and implement control plans governing emissions from all existing and new sources. These plans can include emission limitations for existing stationary sources, transportation control plans to reduce emissions from mobile sources, and pre- construction review of new stationary sources to assure compliance with new source performance standards. The EPA must approve all state implementation plans. Sanctions are given to the EPA to be applied if states fail to submit acceptable

Jan 1, 1985

By Jay S. Silhanek, Vernon E. Andrews

[Introduction] Section 122 of the Clean Air Act Amendments of 1977, Public Law 9595, directed the Administrator of the Environmental Protection Agency, to review all relevant information and determine whether emissions of radioactive pollutants into ambient air will cause or contribute to air pollution which may reasonably be anticipated to endanger public health. In August 1979, EPA published a preliminary report on assessments of public health impact resulting from emissions of radionuclides into air from a broad spectrum of major source categories (1). A section of this document presented a theoretical analysis of the radioactive airborne emissions from several non-uranium mines including iron, copper, zinc, clay, limestone, fluorspar, and phosphate. Since 1978 EPA's Las Vegas Laboratory has been gathering field data on actual radionuclide emissions from these mines to support the earlier theoretical analysis. The purpose of this paper is to present the results of those field measurements in comparison with the assumed values for the theoretical analysis. Data were presented in EPA's preliminary report on both gaseous radon-222 and particulate uranium-238 emissions from non-uranium mines. Most of the emissions data were rough estimates based upon the uranium content of the ore. Preliminary data from a few field studies were also used. Although both the theoretical and field studies by EPA were concerned with radon-222 and radioactive particulate emissions, this paper will concentrate only on the radon effluents. Radon from mines seems to have the greatest potential for possible health effects due to radiation. Data on particulate emissions are presented in other technical reports (2-5). [Theoretical Study] The theoretical emission data are presented in Table I. The estimates for the iron, zinc, and clay mines are based upon preliminary measurements taken by the Las Vegas laboratory. The estimates for the other mines were made assuming that 20% of the total radon-222 in the ore was released during the mining process and the radon release rate from the exposed ore surface was a factor of two greater than that resulting from mining. [ ] Dose assessments for radon from these mines were carried out using model facilities located on generic sites (1). The AIRDOS-II computer code (for estimating dispersion of airborne pollutants) with some minor modifications was used to determine working level exposures to a maximally exposed individual and a regional population. A conversion factor for risk/WL-year(O.021 fatal cancers/person-WL-y) was developed primarily from information on uranium miner exposures (6). This computer code and conversion factor were then applied to the assumed emission rate of radon-222 from each type of mine to develop estimates of working levels, lifetime risks and number of fatal cancers. A summary of this data is presented in table II. [ ] The highest estimated number of cancer deaths per year of operation is 0.05 cancer deaths or 1.0 death due to radon during the 24 year life of a phosphorous mine. For comparison, EPA estimates that underground uranium mines would cause .03 cancer deaths per year of operation in a regional population(1). [Field Study] As a followup to the theoretical study, EPA's Las Vegas laboratory began making measurements in 1978 of actual emissions of radon-222 and radioactive particulates from mine vents at several facilities for each of the industries listed in Table I and II. They were intended to verify general information and radon emissions from EPA's theoretical estimates.

Jan 1, 1981

By Robert B. Parsons

"A t last the legal red tape which has tied up flow-through share financing has been cut. New rules effective for deals signed after 1986 simplify flow-through financing by removing the necessity f or cumbersome agency relationships. But there is no free lunch-the new rules require increased government reporting. And beware federal tax reform promises to have a good look at the new flow-through share rules. IntroductionFlow-through shares have always worked better in theory then reality as an effective financing tool. The concept is straightforward: a transfer of risks, tax deductions, and potential returns. But the mechanics of the old flow-through rules made the transfer of risk impractical to impossible by placing the responsibility for incurring Canadian exploration expense (CEE) on investors. The new rules are significantly more realistic, shifting that responsibility to the issuing corporation. However, every silver lining must have a few clouds around it. In the case of the new flow-through rules, the more obvious negatives are increased reporting requirements and reductions in CEE eligible for flow-through by amounts of assistance received. The new rules are effective for deals signed after 1986, however, so a few old-style deals are still around. Practical Difficulties with Old RulesThe old rules which applied to investments in flow-through shares were structured so as to make it the responsibility of the investor, rather than the issuing corporation, to perform the Canadian exploration expense for flow-through. Since most investors had neither the expertise nor the inclination to incur the CEE, this requirement necessitated the use of cumbersome arrangements whereby the investors would appoint an agent (usually the issuing corporation) to incur CEE on their behalf. Although the issuing corporation might consequently be the party which actually spends the flow-through share funds on CEE, the awkward legal structure of such an arrangement made the investor the ""principal"" incurring the CEE. As such, the requirements of the old rules were met and the investors could receive their flow-through share s."

Jan 1, 1987

By Thomas V. Falkie, R. Venkataramani

Anderson, L. B., 1963, "Multiple Regression Techniques Correlate Experimental Data," Chemical Engineering, V. 70, N. 12, pp. 223-228. Aubert, E. J., Lund, I. A., and Thomasell, A. J., 1959, "Some Objective Six-Hour Predictions Prepared by Statistical Methods," Journal of Meteorology, V. 16, pp. 436-46. Barrett, A. L., 1958, "Alternating Current in Continuous Mining," Mechanization, V. 22, N. 9, pp. 83-86. Bower, A. B., Jr., 1970, "Bit Design: Key to Coal Cutting," Coal Age, V. 75, N. 7, pp. 70-72. Bower, A. B., Jr., 1971, Personal Communication dated April 29, 1971; General Electric Company, Mining and Metallurgical Products Department, Detroit, Michigan. Burt, C., 1950, "Group Factor Analysis", British Journal of Statistical Psychology, V. 3, pp. 40-75. Cady, L., Gertler, M., Gottsch, L., and Woodbury, M., 1961, "The Factor Structure of Variables Concerned with Coronary Artery Disease", Behavioral Science, V. 6, pp. 37-41. Cattell, R. B., 1965, "Factor Analysis: An Introduction to Essentials I. The Purpose and Underlying Models," Biometrics, V. 21, N. 1, pp. 190-215. Christensen, R. W., Heins, R. W., Babcock, W., and Tonn, R., 1971, "The Effect of Material Properties on Materials Handling Processes," Six Month Technical Report, (August 1971) to Advanced Research Projects Agency, U. S. Department of Defense; The University of Wisconsin. Collins, G., 1961, "Factor Analysis," Journal of Advertising Research, V. 1, N. 5, pp. 28-37. Cooley, W. W., and Lohnes, P. R., 1962, Multivariate Procedures for the Behavioral Sciences, New York: John Wiley and Sons, Inc. Cree, J. 0., 1956, "Power for Continuous Mining," Mining Congress Journal, V. 42, N. 10, pp. 49-52. Draper, N. R., and Smith, H., 1966, Applied Regression Analysis, New York, John Wiley & Sons, Inc. Griffiths, J. C., 1966, "A Genetic Model for the Interpretive Petrology of Detrital Sediments," The Journal of Geology, V. 74, N. 5, pp. 655-672.

Jan 1, 1972

By G. H. Thomas, M. C. O’Riordan, S. Rae

INTRODUCTION The British mining industry comprises 228 nationalised coal mines producing some 113 million tonnes of deep mined coal and employing 242,600 persons of whom 185,200 work below ground. There are in addition 174 small privately-owned coal mines employing 1500 persons underground and producing 1.5 million tones of coal. In the non-coal sector there are 108 privately-owned mines producing some 20 different minerals, including tin, wolfram, fluorspar, potash, rock salt, china clay, ball clay and fireclay. There are currently 4,100 persons employed in these mines of whom 2,346 are employed below ground. One mine producing potash employs 870 persons of whom 465 are underground workers. Since 1975 all matters relating to the health and safety of persons at work and of the general public who are exposed to industrial hazards have come within the purview of the Health and Safety Executive (HSE). The Mines and Quarries Inspectorate (MQI) is a constituent part of that organisation and enforces legislation applicable to all mines and quarries. The National Radiological Protection Board (NRPB) is a statutory and independent body that was established in 1970 to advance knowledge and provide information and advice about radiological protection. The NRPB has an agency agreement with HSE to provide advice and services relating to radiological protection, including protection against exposure to radon decay products in mines. There are as yet no statutory requirements controlling exposure to this source of radiation in Britain. Investigations for the presence of radon in British coal mines were begun in the mid 195Os. The concentrations found were of low order, typically around 2 pCi/l (Duggan et al., 1968). This was not surprising since big coal mines are well ventilated to control methane and airborne dust and it is now generally accepted that radon and its decay products do not constitute a health hazard in British coal mines. At one or two small mines where igneous intrusions were in close proximity to the coal workings, slightly higher readings were recorded. The MQI then commissioned NRPB to make investigations at metalliferous mines and in these much higher readings were detected. It was later agreed that the NRPB should undertake a survey of all non-coal mines in Britain to establish the extent of the problem. This survey was conducted mainly in 1973, (Strong et al.,1975) and follow-up surveys at various mines have since been conducted by the MQI. These investigations revealed that radon readings could be high in mines producing tin, haematite and fluorspar. Some small mines working other minerals in the same localities also showed high readings. More recently owners have been making environmental measurements at mines where there was some cause for concern. LEGISLATION AND RADIATION STANDARDS As a result of the survey work for MQI the Board in 1975 recommended an occupational limit of 4 WLM in a year from radon decay products together with a programme of radiological supervision (Strong et al., 1975). The MQI accepted the recommendation and advised employers and employees that the 4 WLM limit should be adopted. The limit corresponds to a concentration of 0.3 WL, equivalent to 30 pCi/l of radon-222 in equilibrium with the decay products, and was in accordance with an earlier recommendation by the International Commission on Radiological Protection (ICRP, 1959). ICRP recommendations are usually endorsed in Britain. It was recognised that some years would probably be required to achieve general compliance, and this is proving to be the case. Some confusion has been caused in Britain by the conflict between successive Euratom Directives on this and other standards of safety. As relative newcomers to the Community, we were not affected by earlier Directives, but the situation is different now. In 1959, the Commission of the European Communities provisionally recommended a maximum permissible concentration for radon-222 and daughters of 3 x 10-7 µCi/cm3, which corresponds to 300 pCi/l (CEC, 1959). The number was affirmed in 1962 (CEC, 1962) and reaffirmed in 1966 (CEC, 1966) but without any specification of the state of equilibrium. In 1976, the CEC again recommended 300 pCi/l, but on this occasion, the daughters were assumed to be present in the same quantities as in unfiltered air (CEC, 1976): this implies 40 WLM a year in poorly-ventilated mines. The formula is repeated in the latest version of the Directive (CEC, 1980), but the value is now said to be an interim one because it might not ensure compliance with the appropriate dose limit. ICRP (1955) recommended 300 pCi/l in equilibrium with the decay products in 1955 and reduced this value to 30 pCi/l for unfiltered air in 1959 (ICRP, 1959), endorsed it for equilibrium conditions in 1976 (ICRP, 1976), and held to it until 1980: these values imply respectively 40 and 4 WLM a year. The recent recommendation of the ICRP (1980) that the annual limit of intake for the decay products should be 0.02 J in a year corresponds to 5 WLM, but there is a rider that reduction should be made for exposure to gamma rays and long-lived airborne radioactivity. An allowance of 20% is suggested for uranium mines, implying 4 WLM a year for the decay products. The

Jan 1, 1981

By R. W. Armstrong, P. C. Jindal

WE should like to point out that Hu and cline.1 in their study of the recrystallization of titanium, have obtained data which appear very important for accurately determining the dependence of hardness on grain size for this material. It has been proposed2,3 that the macrohardness. H. of a poly crystalline material should depend on its average grain diameter, l. in accordance with the relationship: H =H0 + kHl-1/2 [1] where Ho and kH are experimental constants. This relationship follows from the hardness dependence on yield stress or flow stress4 and. thence. the Hall-Petch stress-grain size relations.5'6 Fig. 1 shows the Diamond Pyramid Hardness. Dph. values vs the reciprocal square root of the average diameter of the recrystallized grains, taken from the titanium data reported by Hu and Cline. The data in this figure give a linear relationship for the hardness over a wider range of grain diameters than anyone has previously measured. The data are not linear, for example. on an I-1 or l-1/3 scale. At the very large grain sizes the data are in reasonable agreement with measurements earlier reported by Holden, Ogden, and Jaffee.7 For the grain sizes smaller than 1 µ, which correspond in Fig. 1 to hardness values greater than 150, the material was reported as not being completely recrystallized and, therefore, these data appear less meaningful as far as the hardness dependence on grain size is concerned. However. it has been suggested by other investigators that deformed materials exhibit strengthening due to an effective grain size refinement even in the unrecrys-tallized condition.8-10 Also. Hu and Cline have shown that a change in texture occurs for titanium during the recrystallization process and. especially. following it. The influence of this texture change on the hardness-grain size relation would be expected to be less than that reflected in the unidirectional stress-strain behavior, even for an hcp material. because of the actual combined stress system which applies for the hardness test. For, at least, certain combined stresses, average values of the orientation factors should still occur in the stress-grain size analysis of a material exhibiting a preferred orientation.' We previously suggested3 that the experimental constants. H0 and kH. from the Meyer hardness-grain size relation should be correlated with the Hall-Petch constants, uoy and ky.5,6 Our recent study" of the Hall-Petch relation and the hardness-grain size results which obtain for a number of polycrystalline materials shows that: The inequality [2] is explained by noting that the hardness should be correlated. perhaps, with the flow stress at some value of strain, as suggested by Dugdale,12 and. also, that the influence of strain on the Hall-Petch relation is to increase uo and not change k very much." Normally. Dph values and Brinell hardness values are nearly equivalent to each other and to the Meyer hardness number. For the case of titanium, then. the inequality [2] may be evaluated using the experimental values of ao = 8.0 kg per sq mm and ky = 1.3 kg per mm3/2 obtained from the experiment of Guard.6,13 Thus, (Ho/uo) = 12 and (kH/k3) = 1.3. This research has been supported at the University of Maryland through the Center of Materials Research by the Advanced Research Projects Agency of the U.S. Government.

Jan 1, 1969

By D. L. Rainey, E. R. Goter, W. R. Hudspeth

THE area in which spodumene-bearing pegmatites occur extends from Gaffney, S. C., in a northerly direction to Lincolnton, N. C., a distance of about 16 miles. The zone averages 2 miles in width. Interest in this area was first aroused by the discovery of small amounts of cassiterite in the peg-matites and in greissen which occurs on the walls of some of the pegmatites. Attempts were made from 1880 into the 1920's to mine and concentrate cas-siterite, but there were no successful operations. In 1935 L. M. Williams became interested in the area and began prospecting by trenching and sinking several small shafts. He gradually gained control of a considerable acreage south of the city of Kings Mountain, N. C. Mr. Williams states that he produced some ore from a shaft which he shipped to the Maywood Chemical Co. in the late 1930's. In 1937 G. H. Chambers of the Foote Mineral Co. visited the area and examined several properties, but the lithium market was too small to support the necessary concentrating plant. Early in World War II the Solvay Process Co., encouraged by various federal agencies, acquired the Williams properties and leases and started a drilling program to develop reserves for spodumene mining. A study of this area was also made under T. L. Kesler by the U. S. Department of the Interior Geological Survey. Starting in 1942 a concentrating plant, water supply dams, and shops and other buildings were constructed. The Superior Stone Co., a neighboring crushed stone operator, was awarded a contract to mine and crush the pegmatite ore. Late in 1943 the plant started operations, which were continued until February 1946. A drop in demand for lithium chemicals forced it to close and remain closed for several years. In 1948 the Foote Mineral Co. became interested in assuring itself a source of lithium ore on the North American continent, to be used in the production of lithium ore chemicals, and inspected properties in Canada, South Dakota, and North Carolina. The North Carolina deposits were the most promising. In the fall of 1950 the company leased the Solvay interests with option to buy and acquired additional properties. Renovation of the mill and preparation of the quarry for mining was begun in earnest in January 1951. A new crushing plant was built and construction started in July 1951. The flotation process used was developed in the North Carolina State Minerals Research Laboratory located at Asheville, N. C. Foote is now in the process of expanding its production. The crushing plant is being revamped and much of the old milling equipment purchased from Solvay will be replaced by new. Mining equipment of suitable capacity has been received and is in use. The frontispiece is a general view of the mill. The orebodies consist of pegmatite dikes composed of fine-grained albite and quartz, with varying amounts of mica and spodumene. The latter may amount to as much as 50 pct of the rock, but the overall average is about 15 to 20 pct. Tin, columbite-tantalite, beryl, and other valuable minerals are present in varying small amounts. These dikes, which intruded into the Roan Gneiss underlying most of the Piedmont area, strike approximately N 30 E and dip about 85" to the west. The gneiss has the same strike but dips about 70" west. The dikes lie in a belt extending from Lin-colnton, N. C., to Gaffney, S. C., and passing through

Jan 1, 1954

By Gregg A. Swayre, Roger N. Clark, Stephen J. Sutley, Kathleen S. Smith

Imaging spectroscopy is a relatively new remote sensing tool that provides a rapid method to screen entire mining districts for potential sources of surface acid drainage. An imaging spectrometer known as the Airborne Visible/InfraRed Imaging Spectrometer (AVIRIS) measures light reflected from the surface in 224 spectral channels from 0.4 - 2.5 µm. Spectral data from this instrument were used to evaluate mine waste at the California Gulch Superfluid Site near Leadville, Colorado. Here, the process of pyrite oxidation at the surface produces acidic water that is gradually neutralized as it drains away from mine waste, depositing a central jarosite zone surrounded by a jarosite + goethite zone, in turn surrounded by a goethite zone with a discontinuous hematite rim zone. Leaching tests show that pH is most acidic in the jarosite and jarosite + goethite zones and is near-neutral in the goethite zone. Measurements indicate that metals leach from minerals and amorphous materials in the jarosite + goethite and jarosite zones at concentrations 10 - 50 times higher than from goethite zone minerals. Goethite zones that fully encircle mine waste may indicate some attenuation of leachate metals and thus reduced metal loading to streams. The potential for impact by acidic drainage is highest where streams intersect the jarosite and jarosite + goethite zones. In these areas, metal-rich acidic dace runoff may flow directly into streams. The U.S. Environmental Protection Agency estimates (U.S. EPA, 1998) that mineral maps made from AVIRIS data at Leadville have accelerated remediation efforts by two years and saved over $2 million in cleanup costs.

Jan 1, 2000

THE THIRD INTERNATIONAL GEOCHEMICAL EXPLORATION SYMPOSIUM (Summary Account) This Symposium, co-sponsored by the Canadian Institute of Mining and Metallurgy and the Society of Economic Geologists, was held in Toronto, Canada in April, 1970. Over 700 delegates attended from 26 countries. Ninety papers were presented at the symposium and another 18 papers were read by title. The programme included: An Opening Session, Five General Sessions, a session on Remote Sensing Methods, a session on Geochemical Prospecting for Petroleum and Natural Gas, a session on Primary Halos and Lithogeochemical Methods, and a session on Statistics and Evaluation of Geochemical Data. The delegates were welcomed by Dr J. M. Harrison, President of the Canadian Institute of Mining and Metallurgy and Dr C. H. Smith, Regional Vice-President, North America of the Society of Economic Geologists. Dr D. R. Derry of Toronto delivered the opening address to the Symposium entitled 'Geochemistry-the link between ore genesis and exploration'. Dr Derry considered the various hypotheses on the origin of economic mineral deposits and expressed his belief that the next ten years will show evidence of an increased proportion of ore bodies that owe their origin, at some stage in time, to supergene agencies. He stressed that 'there are no sharp divisions between processes that form and destroy ore bodies at or near surface and those that form or destroy them at a depth of 20 kilometres in the earth's crust. The more we understand about the migration and concentration of metals the more accurately we can apply this knowledge to searching for unknown concentrations, whether at rock surface or at depth. To learn more about these processes of ore genesis we must rely on geochemical studies co-ordinated with field observations'. The five general sessions included accounts of progress in geochemical prospecting in different countries of the world, case histories describing the application of soil, stream sediment, geobotanical and biogeochemical techniques, papers on the behaviour of different elements under varied environmental conditions, discussions on analytical methods and the use of stable isotopes in mineral exploration. It is anticipated that the proceedings of the Symposium will be published late in 1970 or early in 1971 as a Special Volume of The Canadian Institute of Mining and Metallurgy. All registrants at the Symposium will receive a copy of this publication and copies will be available for purchase. At a special meeting called during the Symposium, charter members of the Association of Exploration Geochemists approved a constitution and elected an interim Council which will organize procedure and formulate policy during the coming year. The interim president of the Association is J. Alan Coope, Newmont Mining Corporation of Canada Limited, Toronto, Canada. More information on the constitution and membership in the Association will be distributed to learned societies and technical magazines in the near future. Membership will be open to exploration geochemists in all countries of the world. SOUTH AFRICAN COUNCIL FOR PROFESSIONAL ENGINEERS Report on Registration The Professional Engineers Act (Act 81 of 1968) came into force on the 14th February, 1969. At the time it was recognised that the success of the Act would depend in large measure on the extent to which engineers in South Africa would become registered professional engineers in terms of the provisions of the Act. The promulgation of the Act and its provisions relevant to registration were the subject of considerable publicity during 1969. This has resulted in a rate of application for registration far beyond the capacity of the very active committees set up for this purpose by the South African Council for Professional Engineers (SACPE). To give some idea of the task before these committees and before SACPE itself, which must ratify each case,

By Armine F. Banfield

Selection of a plant site is becoming increasingly more difficult and important, mainly due to advances in technology, antipollution laws and changing economic, social and community conditions. Discussion falls naturally under three headings: economic considerations, terrain considerations and environmental considerations. Aside from acquisition of surface rights, problems having to do with terrain, or topography, usually can be dealt with by management alone. Economic considerations largely involve decision-making by management plus negotiations with government regulatory agencies acting under set rules. Environmental considerations, such as air and water pollution, townsites, housing, schools, noise abatement, appearance, surface rehabilitation and the like usually are under the control of federal, state or municipal bodies with a large degree of decision-making. Successful solution of environmental problems often requires lengthy negotiations, during which public relations by the mining company play an important part. Existing union regulations or customs may confine decision- making and the establishment of wage rates, working conditions and regulations. These usually require considerable planning and negotiation. Initial production often is delayed by formal negotiations involving environmental considerations. Surface facilities usually can be divided into two broad categories: those for concentrating ores--such as gold, silver, base metals, low-grade iron ore and potash-which should be close to the mine to reduce ore-transportation costs to a minimum, and those where the ore is shipped elsewhere for treatment, such as direct-shipping iron ores, complex high-value ores requiring specialized treatment and ores from which special products are derived for local markets. The long-term aspects of plant-site selection too often are given no or insufficient consideration because of immediate financial limitations. As a result, additional capital expenditures may be required later for relocation of townsites, roads, railroads and plants to provide additional room for extension of open-pit operations, tailings disposal, storage, or danger to foundations through underground subsidence or open-pit mining. In the past, hillside sites for concentrating plants were preferred to take advantage of gravity-feed methods The modern trend, however, is to place as much equipment as possible on approximately the same level. Some costs relating to plant sites are included in this section. They are ranges as of the year 1970, and are offered only as general guides. Such costs will vary widely with geographical location and, of course, are subject to escalation due to increases in wage rates and cost of materials. Items in the bibliography contain more detailed and comprehensive data on specific subjects. Most contain bibliographies of their own.

Jan 1, 1973

Probabilistic seismic hazard analyses (PSHA) have now gained wide acceptance in the development of design criteria for major projects. When used with regional criteria the procedures have also allowed the preparation of more rational seismic zoning maps. Seismic zoning maps using various levels of results from PSHA studies around the Pacific Rim now include Canada, Indonesia, New Zealand and the United States. Some Pacific Rim countries such as Chile where the seismic exposure is dominated by subduction events have no subdivision into separate zones.Approaches to risk based zoning are being considered in several Pacific Rim countries including Australia. Australian studies must face problems similar to parts of the Eastern United States where seismic activity is low with irregular and infrequent occurrences of moderately large earthquakes. The perception of the seismic exposure by both regulatory agencies and the public at large is different when considering areas of low seismicity. There is therefore a need to make different interpretations of the results of PSHA studies in these areas of low seismicity. The aim of this paper is to explore some of these differences by comparing the results from two site specific studies from areas with widely differing seismic activity rates.

Jan 1, 1990

By Samuel H. Dolbear

THE value of a mine is basically dependent on its capacity to yield profits. Since the ore must be mined, treated, and sold, some of it in various future years. there is a risk involved as to future costs, selling price, and working conditions. It cannot be expected that the economic condition existing at the time of valuation will continue unchanged for long periods in the future. During the past 20 years, mineral production in the United States has been conducted under a changing economy in many respects more exacting than that applied to other businesses. There have been increased production incentives, technical aid, exploration of privately owned mineral deposits by government at federal expense, and liberal loans for development and equipment, with risk partially assumed by government.. Some of these benefits have been counterbalanced by price ceilings, consumption controls, and stimulation of competition from foreign producers who have been offered the same advantages extended to American operators. For the present, mines will operate under a government policy directed toward reducing federal aid and control. The tenure of this change will depend upon future elections and the status of foreign relations. War and threat of war are now of the most vital significance to the mineral industries. Other factors which influence cost of production, markets, and price of mine output might be classified as Acts of God or Acts of Government. In some countries expropriation and the difficulty of exporting earnings or investment returns are risks that must be considered by foreign capital. Recognizing that this retards American investment in foreign countries, the Mutual Security Agency offers insurance against such expropriation and guarantees the convertibility of capital and profits. Since it is impossible to predict with certainty either cost of production or selling prices of metals for long periods, some assumptions must be made as to profits in the future. The basic assumption must be that the price of the company's product will vary in proportion to changes in operating cost. There is often a lag in this reaction, however, for prices of minerals are generally more sensitive to declines and less sensitive to increases than are costs. This reflects in part the resistance of labor to downward wage revision and a corresponding alertness in realizing its share of price advances. Some labor contracts include automatic adjustments to metal prices. Notwithstanding the complexity of the, problems involved and the difficulty of weighing their effect on value, such risks may be appraised with reasonable accuracy and a rate of earnings adopted that is compatible with the risk. It is, of course, possible to revert to a yardstick of value such as the commodity dollar, which has been advocated from time to time, but while revaluation in 1933 disturbed public confidence, the theoretical gold dollar continues to be the standard of greatest stability. Its gain or loss in purchasing power is reflected ultimately in cost of production and selling price of the mine product. At present 35 dollars are allocated to one ounce of gold. Measurement of Risk In the application of the Hoskold and most other formulae, a yearly dividend rate commensurate with the risk involved is set aside out of annual earnings. If the risk is great, this rate may be 15 to 25 pct of the amount invested. The remainder is placed in a sinking fund invested in safe securities such as high grade bonds or conservative equities, and the interest or dividends from these securities are added to the sinking fund. The sum of these sinking fund payments and the compounded interest at the end of the mine life is taken as the value of the mine. Admittedly the decision as to the size of the risk rate is the most difficult element in valuation and one requiring the most exacting consideration. It is necessary to look years ahead in an effort to determine future costs, market prices, demand, competition which may develop, including that of substitutes, and other influences common to the mine and to the region in which it is situated. Another phase of risk is the enactment of unfavorable legislation, taxes, and what appears to be an alarming spread of nationalization and expropriation. Capital is sometimes borrowed from the government to finance strategic production. Such loans may be collectable only out of production and involve no liability otherwise. Valuation in these cases must recognize the effect of such a reduction in liability. Offsetting some of these risks are the possibilities of mechanization and other cost-reducing discoveries, improvements in mining and treatment methods, new uses for minerals and metals, and normal growth of markets. In this paper, the terms risk rate, dividend rate, and speculative rate are synonymous. Safe rate and redemption rate are also used interchangeably. These alternatives are used here because they are commonly found in the literature on mine valuation. In Michigan, the State Tax Commission has long employed a risk rate of 6 pct in its valuation of iron mines. There the outline of reserves is well established and operating costs and conditions are based on adequate experience. The following comment on rates appears in the report of the Minnesota Interior commission on Iron Ore Taxation submitted to the Minnesota Legislature of 1941.1 Most engineers agree that 7 percent for the specu-lative rate is "an absolute minimum". C. K. Leith in

Jan 1, 1954

By R. Addison, P. V. Avotins, E. Martinez, L. A. Haas, D. K. Mortenson, E. EI-Shall, R. D. Kulkarni, M. D. Flavel, S. Chong

Mineral processing activities in general reflected the economic ills of 1981 and early 1982, but in some areas the depressed state of the industry resulted in increased activity. As were all aspects of the minerals industry, processing plant operations were severely affected by the recession-prone economy, by sagging prices for primary metal products-copper, molybdenum, nickel, iron, manganese, and especially uranium-and numerous shutdowns and layoffs. Copper production by major producers in Arizona and Utah was severely curtailed; Amax, the major US molybdenum, producer did considerable belt-tightening; and the uranium industry was in a state of disaster. Even the precious metal superstars-gold and silver-were affected, with a steady decline throughout the year in world market prices. Perhaps hardest hit have been newly developed properties, particularly in the uranium industry, and old-line properties where historical development impacts today. No longer can such properties afford the luxuries, for example, of a long haul distance between mine and plant or continued use of antiquated facilities. Surprisingly enough, the very state of the economy has caused increased activity in some sectors of the mineral processing industry. In mill design, although large projects have been tabled, smaller projects have gone on, with innovations in design, often for cost-saving reasons, that will affect future designing approaches. Economic restrictions are impacting on mill flowsheets as researchers look for improvements and better, less expensive techniques. Other unit processes-hydrometallurgy, pyrometallurgy, concentration, materials handling-are impacted by the need for a better, less costly product. Although at the end of the first quarter of 1982, no major environmental legislation had been enacted, rumors persist that there will be a loosening of some of the stricter standards, both in the requirements themselves and in the time allowance for implementation. The year had seen some relaxation in how current legislation and standards are administered. For example, in OSHA (Occupational Safety and Health Administration) operations, there has been a shift toward voluntary checking of industry compliance with work rules, rather than emphasis on agency inspections. However, the industry continues to view environmental factors as having major influence on future operations and efforts to design for environmental safety are becoming almost as important as the processes themselves. Throughout the industry there has been a further focussing on project management, recognizing the necessity for tight control of budgets and schedules-and the systems used to effect them. Materials Handling Review prepared by A. T. Yu, ORBA Corp. The frenzy of coal export activities has continued into 1981. Many modern export terminals are now in construction while others have either been held up or cancelled. Economics and environmental permits have been some of the major problems. Currently under construction are terminals in Newport News, VA; Charleston, SC; and Baltimore, MD. Expansion of existing facilities at Mobile, AL, and New Orleans, LA, is also well under way. A wide variety of systems and components are being used. They include traveling shiploaders, tunnel and bucket wheel reclaim¬ers, stackers and high line trippers, and bottom and side dump-type car dumpers. Manufacturers from Japan and Europe have been participating along with domestic suppliers. As an attempt to avoid environmental problems, a system of loading and unloading coarse coal

Jan 5, 1982

Experiment of Improving the Quality and Decreasing the Impurity of Titanium Concentrate in Panzhihua Mine in China

Sep 13, 2010

By J. W. Chester

The rapid depletion of zinc-lead ore reserves and the rising costs of exploration have been major factors in the decline of mining activities and explorations for additional reserves in the Tri-State mining district. There is a need to develop new or adopt known, improved exploration techniques that will appreciably lower the costs of exploration. Demonstration of the practicability of using improved techniques to indicate, rapidly and cheaply, mineralized areas or geologic structures where more intensive explorations are justified could stimulate the search for and discovery of additional ore reserves. Various operators in the Tri-State district have used geophysical surveys to some extent since 1928 to guide exploratory drilling. Some geophysical investigations have also been made in the district by the State Geological Surveys of Kansas (11)3/ and Missouri (8, 13) and by Federal agencies (16), with the objective of directing exploratory drilling to areas where geologic conditions favored ore deposition. Many factual data obtained have not been published. The investigations generally have not been broad enough to permit conclusive evaluation of the usefulness of the geophysical techniques in all parts of the district.

Jan 1, 1959

By H. H. Evinger, M. Muskat

Although the shooting of oil wells for the purpose of increasing production has been practiced since 1866, present-day shooting technique has been arrived at almost wholly by a process of trial and error. The difficulties attending either a theoretical analysis of the problem or an experimental attack become apparent when one actually embarks on a theoretical investigation or attempts to formulate an intelligent experimental program. The literature on the subject consists mainly of descriptions of current practice, scattered eye-witness accounts of events following the shooting of a well, and vague speculations on the mechanical processes involved. In contrast to quarry blasting, the results of oil-well shooting cannot be determined by means of visual inspection, and it is perhaps for this reason that only one attempt at what approaches a direct experimental attack has been reported in the literature.' In these experiments, charges of liquid nitroglycerin were exploded in holes drilled in a sandstone outcrop. In order to observe the character and extent of the resulting fractures, the rock was blasted away so as to expose the original shot holes. After all this had been done it was found impossible to distinguish the fracturing due to the original shots from that due to the subsequent blasting. The enlargement of the holes due to the pulverizing action of the shots was measured and an attempt was made to determine the effectiveness if sand tamping. Only five shots were made and few definite conclusions could be drawn. Some small-scale experiments to deter-mine the effect of tamping were performed by Snelling and IIalL2 Small charges (zo grams) of dynamite were detonated at the bottom of a cylindrical hole in a lead block and the resulting enlargement of the hole was taken as a measure of the effectiveness of the explosion. It was found that when the shot was tamped with a sufficient amount of sand or clay, the volume enlargement was approximately double that found when no stemming had been used. The properties of the explosives have been the subject of much study by the manufacturers, the U. S. Bureau of Mines, and various other agencies. For example, velocities of detonation for many commercial explosives are to be found in the Blasters' Handbook, issued by the Du Pont company. Many other properties are given in a treatise on the subject by Naoum.~ The shock wave that accompanies the detonation of high explosives has been studied photographically by Payman4 and others. The hydrodynamical theory of the shock wave has received much attention, and an extended theoretical treatment is given by Bateman.6 Two aspects of the well-shooting problem will be considered in this paper; namely, the fracturing of subsurface strata, and possible damage to casing. With respect to the former of these, several calculations have been made giving the stresses in the rocks surrounding the shot. In order to arrive at numerical results at all, however, it is necessary to introduce a great many simplifying

Jan 1, 1941

By M. Muskat, H. H. Evinger

Although the shooting of oil wells for the purpose of increasing production has been practiced since 1866, present-day shooting technique has been arrived at almost wholly by a process of trial and error. The difficulties attending either a theoretical analysis of the problem or an experimental attack become apparent when one actually embarks on a theoretical investigation or attempts to formulate an intelligent experimental program. The literature on the subject consists mainly of descriptions of current practice, scattered eye-witness accounts of events following the shooting of a well, and vague speculations on the mechanical processes involved. In contrast to quarry blasting, the results of oil-well shooting cannot be determined by means of visual inspection, and it is perhaps for this reason that only one attempt at what approaches a direct experimental attack has been reported in the literature.' In these experiments, charges of liquid nitroglycerin were exploded in holes drilled in a sandstone outcrop. In order to observe the character and extent of the resulting fractures, the rock was blasted away so as to expose the original shot holes. After all this had been done it was found impossible to distinguish the fracturing due to the original shots from that due to the subsequent blasting. The enlargement of the holes due to the pulverizing action of the shots was measured and an attempt was made to determine the effectiveness if sand tamping. Only five shots were made and few definite conclusions could be drawn. Some small-scale experiments to deter-mine the effect of tamping were performed by Snelling and IIalL2 Small charges (zo grams) of dynamite were detonated at the bottom of a cylindrical hole in a lead block and the resulting enlargement of the hole was taken as a measure of the effectiveness of the explosion. It was found that when the shot was tamped with a sufficient amount of sand or clay, the volume enlargement was approximately double that found when no stemming had been used. The properties of the explosives have been the subject of much study by the manufacturers, the U. S. Bureau of Mines, and various other agencies. For example, velocities of detonation for many commercial explosives are to be found in the Blasters' Handbook, issued by the Du Pont company. Many other properties are given in a treatise on the subject by Naoum.~ The shock wave that accompanies the detonation of high explosives has been studied photographically by Payman4 and others. The hydrodynamical theory of the shock wave has received much attention, and an extended theoretical treatment is given by Bateman.6 Two aspects of the well-shooting problem will be considered in this paper; namely, the fracturing of subsurface strata, and possible damage to casing. With respect to the former of these, several calculations have been made giving the stresses in the rocks surrounding the shot. In order to arrive at numerical results at all, however, it is necessary to introduce a great many simplifying

Jan 1, 1941

By S. Srinivasan, R. Coté

"India is undergoing a massive electrification program using local coal to provide fuel for thermal generating plants. The Rajmahal mine in northern Bihar is scheduled to produce coal at the rate of 10 million tonnes per year by the end ofa sixty six month contract with MET-CHEM Canada Inc. for mine development. In order to control maintenance performance and warehouse inventory MET-CHEM is installing some proven computer-controlled programs and will provide extensive training to ensure that the systems are properly used. The programs are Maintenance Planning and Control System (MPCS) and Materials Management System (MMS), both of which were developed and used by Quebec Cartier Mining Company at its iron ore mine in northern Quebec. In addition, a Predictive Maintenance Program (PMP) using vibration analysis will be introduced . This paper discusses the three systems.IntroductionIndia is currently undergoing a massive countrywide industrialization and electrification program. Most of the power will be supplied by coal-fired thermal electric plants.One of the mines being developed as part of the over-all program is the Rajmahal Open Cast Coal project in the Godda District of Bihar, approximately 270 km north , and slightly west of Calcutta.The project is based on an agreement signed in January, 1989 between two government organizations - Canadian Commercial Corporation (Ccq and Coal India Limited (CIL). MET-CHEM Canada Inc. (MET-CHEM), an international consulting engineering organization which has worked in India since 1976, is CCCs Canadian executing agency for the project. METCHEM was the engineer-constructor and mining associate for the development of the 7.5 mtpy Kudremukh Iron Ore Project. This US$430 million project was completed on schedule and under the original budget estimate. The Rajmahal deposit is the responsibility of Eastern Coalfields Limited (ECL), a subsidiary of CIL. The project is to produce coal at the rate of 10.5 million tonnes per year in 1994."

Jan 1, 1991

By Tim Mann

"Like other operating mine sites, Placer Dome Inc. - Campbell Mine has taken important steps over the last few years to address environmental issues.This paper will provide specific insights into the implementation of an environmental management system at Campbell. In particular, it will focus on how Campbell developed its plan of action; the lessons that have been learned; the over-all steps that are being taken to enhance environmental stewardship and effectively manage relationships with key stakeholders.IntroductionThe development of an Environmental Management System at Campbell Mine has been part of a general development in management practices which has taken place at the mine during 1990. This paper will discuss the components of the management system in the topic areas of: direction setting; environmental organization; issue assessment; emergency response plan; training ; monitoring/verification; reporting and data management; and relationship management.Although this paper focuses on environmental management systems, the development of this system has partly been a function of responses to other issues which have been addressed concurrently with environmental concerns. These other issues include development of operations management, human resources practices, and safety management practices at the mine. As the Environmental Management System developed, various stakeholders associated with local environmental concerns were identified. This group of stakeholders include the local community; municipal, provincial and federal governments; government agencies; Campbell employees; and the Placer Dome Inc. Corporation."

Jan 1, 1991

By J. Coxon, G. W. Walker

The paper describes the discovery, location and events concerning three types of heating which have occurred in recent years: a) in a district being salvaged, b) in the shaft pillar at an air-crossing, and c) in the gate side of a production district, all of which have occurred in the Beeston Seam at collieries in the deeper eastern part of the area. The paper describes the precautions, air sampling arrangements, training methods and codes of practice which have been adopted at collieries where spontaneous combustion is, or is likely to be, a hazard. The air samples taken from behind the stoppings following the sealing off of the salvaging district are examined and interpreted. The problem of effectively sealing off where more than two stoppings are required is made apparent. Other lessons have been learned as a result of these heatings and are described in the paper.

May 23, 1905