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By W. A. Haley

As far back as 1939 state laws have required reclamation of mined lands. Reclamation has been the topic of many discussions and presentations, especially since the late 1960's. In the past ten years many states have added legislation concerning the reclamation of coal-mined lands. In the near future, it seems certain that some federal regulations will be passed that will set minimum guidelines for the states to regulate. Besides the requirement of returning the land to the approximate original contour, future regulations will more than likely demand replacing topsoil from one to five feet thick. As regulations become more stringent, costs will rise accordingly. Since no one has developed a machine that can do all reclamation work by itself, it is necessary to review in detail the tools available and to select the most economical means.

Jan 1, 1976

By J. C. White

"During the early development of the Mattabi Mine in 1970, discussions with the Ontario Government revealed their policy of prohibiting, as much as possible, the development of new, isolated, single-industry townsites. Subsequently, Mattabi located its first housing in the Township of Ignace, which is situated 50 miles from the site of the mine and plant. Over 200 employees now commute 100 miles daily to and from work.This paper describes the experience gained and discusses the advantages and disadvantages of a remote townsite."

Jan 1, 1976

By Toshimitsu Kokubo, Yoshio Yamagata, Tadao Moro, Kenji Tomita

Owing to the traffic jam in collection, and transportation of wastes, the air- and water- pollution in incineration plants, and the sanitary trouble in reclaimed land, it seems that the defective existing system of the solid waste treatment in Japan can not follow the change in quality and the increase in quantity of solid wastes. Under these situations, the objective of the municipal solid waste treatment must be to actualize the pollution-free system for environmental protection and the resources recovery system for resource- and energy- saving. From this point of view, AIST of Japan is now engaged in the research and development of the resources recovery system from municipal solid wastes. This paper reports on the outline of the development of resources recovery technology in Japan, including the AIST's project on this matter.

Jan 1, 1976

By James E. Jones

The coal mining industry is being called upon to vastly increase production in the coming years. Many mining operations will have to prepare an environmental impact report of some kind and all will have to comply with various types of environ- mental regulations. Therefore there is a great need within the industry for access to environmental data, information, and literature. This paper discusses the informational resources available, the current lack of access to these resources, and the Environmental Data, Information and Literature (EDIL) Bank of the Kentucky Institute for Mining and Minerals Research. The bank's major emphasis concerns the environmental, social and economic aspects of producing clean solid, liquid, and gaseous fuels from coal. The data bank promotes information interchange between other related governmental and private projects and the energy development community.

Jan 1, 1976

By Richard C. Neavel

Among the many compositional parameters used to judge the quality of a steam coal is the fouling factor of Attig and Duzy1 [% base in ash % acid in ash X % Na20] in ash. The higher the fouling factor, the more likely the heat transfer surfaces of the boiler will acquire a deleterious deposit of sintered ash. While examining the elemental composition of ash from various size and gravity fractions of coals from Illinois, we noticed that variations in the fouling factor were attributable mostly to variations in the sodium content. Further, sodium content was essentially the same in all sink-float fractions from a given coal. In other words, sodium was related neither to the ash nor to the organic material. We therefore concluded that the sodium was most likely in the pore water, which was approximately a constant proportion of all fractions. This led to the supposition that the sodium might be removable through water extraction. This supposition tended to confirm the observations of Daybell,2 Daybell and Gillham,3 and Gluskoter and Ruch4 that much of the sodium in coals existed as water soluble sodium ions. In passing, it should be noted that most sodium in Western U.S. coals (i.e., Wyoming, North Dakota, Montana) is not water soluble, but rather is fairly strongly held in association with the organic material (ion-exchanged).5 Because data reported in the literature were not very conclusive about the typical proportions of sodium that might be removed by water extraction, and because there were few data indicating extraction rates, and finally, because our calculations showed a favorable economic incentive to lower sodium contents, we initiated an experimental program to investigate water extraction of sodium from Illinois coals.

Jan 1, 1976

By Ted H. Eyde

Both private industry and the Interior Department have become alarmed about the enormous amount of Federal land that has been withdrawn from appropriation either under the Mineral Leasing Laws or the Mining Law of 1872. According to a recent article by Gary Benethum and L. Courtland Lee, governmental actions have withdrawn nearly 400 million acres from the operation of the Mining Law of 1872 and over 500 million acres from the Leasing Laws. An addition al 100 million acres for the Mining Law of 1872 and 70 million acres for the Leasing Laws are either encumbered or being managed in such a way as to constitute a defacto withdrawal from mineral development. This means simply that mineral exploration end development under the Mining Law of 1872 is either prevented or discouraged in an area the size of the states of California, Arizona, Washington, Oregon, Nevada, Utah, Idaho, and one half of Colorado combined. Under the Mineral Leasing Laws, exploration and development is either prevented or discouraged in an area equal in size to all the states east the Mississippi River, except Maine.

Jan 1, 1976

I am wearing two hats today. When the invitations went out to participate in this forum, two were received in the head office of the Department of Lands and Survey - one addressed to the Director-General of Lands and one to the Chairman of the National Parks Authority. It seemed logical that as the department is responsible to the Government for the administration of the National Parks Act 1952, we should respond by providing one speaker to cover both the department's interests and those of the National Parks Authority. I hope, however, that this will not blur the clear distinction which exists in the context of the mineral industry between Crown land on the one hand administered by the department for the statutory Land Settlement Board and national parks and allied reserves on the other hand which are the responsibility of the National Parks Authority.

Jan 1, 1976

By Rodolfo V. de la Cruz

This paper describes the development of a modified Goodman Jack method for determining the mechanical properties of rock masses in situ. The modified method consists of the basic borehole loading device and a friction-strain-gauge measuring module. The friction gauges, located in the central portion of the jack, are impressed on opposite quadrants of the borehole walls and the remaining quadrants are loaded by the borehole jack with a uniaxial self-equilibrating pair of forces. The tangential strains generated at the borehole walls are thus measured concurrently with the loading. For ideal elastic materials, the tangential stresses at any point on the borehole walls due to jack loading can be obtained from closed-form analytical solutions utilizing the complex variable method. Complete stress-strain curves for the rock material can then be directly obtained from the tangential strain measurements and the calculated tangential stresses at those points. The continuous data are considerably more significant and reliable than averaged or point data obtainable by other current in situ measuring techniques. Moreover, the advantages inherent to the original Goodman Jack method are also obtainable in the modified method. The suitability of the new method was demonstrated by carrying out a number of laboratory measurements in large specimens of reinforced concrete, aluminum and granite blocks. The results of actual field measurements carried out in sandstone and granite quarries were found comparable with those obtained in the laboratory.

Jan 1, 1976

By C. R. Pelley

This paper is intended to describe the utilization of Western subbituminous coal as used in a utility-sized steam generator. It compares this coal's characteristics with those of a typical Midwestern and Eastern coal as a base and reviews the various design considerations when blends of these coals are used. The effects of blending various low-sulfur Western coals with Midwestern or Eastern coals to achieve a predetermined sulfur dioxide emission and the resulting alteration in the coal characteristics as they apply to utilization are also reviewed. The blending of coals as one means of complying with sulfur dioxide regulations will take on increasing importance as the various deadlines for compliance with new and existing regulations approach. We must first consider the availability of these low-sulfur coals; and insofar as the Eastern low-sulfur coals have been mined for many years, we have focused our attention on the availability of the coal reserves west of the Mississippi River in the United States, as this is the area to which many people are turning in order to meet this requirement.

Jan 1, 1976

By Irving D. Cohen

In order to overcome our reliance upon foreign energy sources for both crude supply and finished products, we must realize the goals proposed by Project Independence. In general this involves expanding production of existing and new oil, gas, and coal resources, utilizing and improving nuclear technology and the developing of new energy sources such as solar, geothermal, oil shale, tidal, wind and stimulation techniques. There is a continuing debate, both in the scientific community and the consuming public as to the potentiality of nuclear power generation being cost effective and environmentally and safety conscious. The development of new sources of energy does not occur overnight; it is rather a continuing effort in time and money to achieve the goal of providing energy to an ever increasing demand. The public has been accustomed to the availability of energy whenever and wherever it was needed. The era of "energy gluttony" has begun to fade into the realm of "energy awareness". Unfortunately, it required the action of another country to bring the picture that has been discussed many times in the past by energy suppliers into correct focus. Nevertheless, the public responded by conservation efforts to reduce energy wastefulness. Still, the demand for foreign importation of energy supplies is on the rise. What is our recourse? The largest known unexploited energy resource available in the United States is our coal resources. Moreover, the Department of the Interior has noted that 63 counties in Montana, Wyoming, and the Dakotas hold 60% of the nation's least expensive strip minable coal. This western coal is the most abundant and least costly Fossil Fuel in the United States. It is acknowledged that western coal is an important input in meeting the energy needs of our nation.

Jan 1, 1976

By F. W. Schweitzer

The trend toward development of large low grade ore bodies has accelerated in recent years. It has been estimated within the copper industry that "porphyry" type deposits will provide the bulk of copper production during the next 30 years. It is further estimated that in these deposits the average ore grade by the year 2000 will be 0.25% copper (1). Many of the new porphyry copper discoveries are of such extremely low grade that they are particularly sensitive to small fluctuations in cost variables and copper prices. Because haulage constitutes a major item of surface mining expense, the capability to transport large tonnages of material at increasingly lower unit costs is vital to the profitable operation of many of these mines. High capacity conveyor belts appear to have considerable promise in this area. The heaviest use of high tonnage conveyors has been in the brown coal industry in Germany. In the past 20 years several such installations have proven successful. In addition to the German installations, several other successful systems have been put into operation. Some examples are: The Oroville Dam project in the United States; the tar sand operation in Northwest Canada; the pre-mine stripping and mining of the Twin Buttes Mine in the United States; the Kursk Magnetite 'dine in the U.S.S.R.; and the Nchanga Copper Mine in Zambia. Most of the systems mentioned are handling alluvial material consisting mainly of fines. The noteworthy point regarding these installations is their high continuous capacity. One of the largest lignite mines in the world is at Fortuna, Germany, where over 15,700 tons (15,250mt) per hour of overburden is transported on an 87 inch (221cm) wide belt running, at over 1000 feet (305m) per minute.(2). Another example is a 20,000 ton (18,150mt) per hour system for loading iron ore into barges on the Great Lakes (3).

Jan 1, 1976

By Arthur M. Hartstein

The Federal Bureau of Mines, under a contract with Ultrasystems, Inc., investigated the thermal oxidative degradation characteristics of conveyor belts used in underground mines. This included the determination of smoke evolution, glow characteristics, char yields, and the identification and quantification of all volatile decomposition products in the form of gram of specific product formed per gram of belt sample tested. In addition to these investigations, degradation studies were conducted on some pure ingredients used in conveyor-belt formulations. Three basic classes of belts were investigated: neoprene, polyvinyl chloride, and styrene-butadiene rubber compositions. The studies indicate that styrene-butadiene-based belts exhibit good flame resistance and are the least hazardous in regard to overall formation of toxic decomposition products. Under this program, thermogravimetric analysis was definitely established as a method of material differentiation.

Jan 1, 1976

By Daryl R. Tweeton

The Bureau of Mines conducted experiments to measure the influence of environment on the friction and wear of a steel-quartz system at several speeds and loads. In each test a quartz block was pressed against a rotating ring of low-carbon steel. Environments used were moist air, dry air, dry nitrogen, water, aqueous oleylarnmonium acetate (ClsH35NH3+-OCOCH3), and aqueous aluminum chloride (A1C13). The sliding speeds were 2.2, 13, and 33, cm/sec, and the loads were 6.8 and 13.6 kg. The coefficient of friction, the wear, and the roughness of the surfaces were measured, and the wear debris was examined. The coefficient of friction was significantly lower in moist air at 2.2 cm/sec than for any other combination of environment and speed employed, and was generally an inverse function of the oxidizing ability of the environment. The coefficient of friction increased somewhat with increasing load. The wear of the steel rings was greatest in dry air at all speeds and loads. The wear of the quartz blocks at 180 rpm was greatest in dry air, but at 12 rpm it was greatest in nitrogen. Friction and wear in aqueous oleylarnmonium acetate and in aqueous aluminum chloride were similar to effect in water alone.

Jan 1, 1976

By G. W. Murrie, W. P. Diamond, S. W. Lambert

A geologic study of the Mary Lee Group of coalbeds in the Black Warrior coal basin was undertaken to examine coal stratigraphy and determine regional trends and extent of the coalbeds. The area investigated encompasses 835 square miles in Jefferson, Walker, and Tuscaloosa Counties, Ala. More than 700 core logs were used to construct a structure map, coal, interval, and overburden isopachs, and cross sections. There is evidence that structure affected sedimentation. Coalbed isopachs indicate the Mary Lee Group was deposited in fluvial-deltaic and low-lying coastal plain environments. The Mary Lee coalbed is the only coalbed which is continuous throughout the area, commonly with two benches which have a combined thickness of 2 to 12 feet. The Mary Lee coalbed changes rank in the basin from high- through medium- to low-volatile coal. The methane gas potential of the Mary Lee Group coals is estimated to be greater than 1 trillion cubic feet. There is an excellent correlation between the orientation of surface cleats with those measured underground in the Mary Lee coalbed. The face cleats roughly parallel the axes of the area's folds and trend northeast-southwest.

Jan 1, 1976

By Ben L. Seegmiller

How to obtain optimum slope angles for future open pit mines using the rock mechanics approach is the subject of this paper. In the past ten years significant developments in open pit rock mechanics have come about. This has been due to the mining industry's need for the steepest, yet safe, pit slope angles attainable. Requirements for economically achieving slope stability and the actual payoff that may be achieved through stability studies have been previously discussed', by stability engineers. While the emphasis has generally been placed on the concept of "stable slopes" in the past, it is suggested that emphasis now be placed on "optimum slopes" or "optimum slope angles". A definition of an optimum slope angle is one which (1) is as steep as possible and practical from orebody and mining constraint standpoints and yet, (2) maintains the accepted standard of safety defined by a safety factor against failure and/or a probability of failure. In other words, the emphasis is placed on achieving practical stability results as defined by safety and economic considerations, as opposed to simply achieving stability. The essential purposes of this paper are to (1) outline the need for optimum slope angles, (2) discuss the procedures for using the rock mechanics approach in slope angle design for a future open pit and (3) specify the end results that may be achieved by using such an approach. While the basic concepts and recommendations outlined in this paper may be equally applicable to soil as well as rock slopes, the emphasis and procedures have been directed at rock slope angle design.

Jan 1, 1976

By Subhas G. Malghan

Feldspathic deposits occur widely throughout the United States, but North Carolina, California, Connecticut and South Carolina accounted for over 80% of the total domestic feldspar output for the year 1973.1 Pegmatites and granites constitute the major feldspar reserves of the United States,2 and in addition, feldspar is produced as a by-product by firms whose major products are spodumene and mica.3 Feldspar is concentrated by hand-cobbing and flotation; the latter forms the major method of separating and concentrating feldspar. Feldspar flotation is practiced in the United States, Mexico, Finland, Norway, West Germany, Japan and the USSR. According to the U. S. Bureau of Mines estimates, the production of feldspar in the United States and rest of the world were 704,000 tons and 2,514,000 tons respectively. Feldspar is principally used as a flux in making glass, pottery, porcelain, enamel,-tile and other ceramic products. In recent years, the domestic feldspar industry is faced with a number of problems. As a result of increased cost of energy and the introduction in 1972 of new legislative programs relating to air, water, and noise pollution, land-use restrictions, and mined-land rehabilitation, the production costs have increased. Apart from the increased cost of operation, an operational problem exists with the feldspar producers in North Carolina, especially those in the Spruce Pine area. This problem is concerned with the use of hydrofluoric acid in the feldspar flotation. Feldspar producers in Spruce Pine, North Carolina have been discharging process waste water into the North Toe River. The mill waste water contains active fluoride ions. Fluoride in excessive concentrations is undesirable in waters used for drinking. It is stated that water

Jan 1, 1976

By D. L. Paulson

The Bureau of Mines is investigating pyrometallurgical and chemical methods for extracting copper from sulfide ores under conditions that provide for control of gaseous and solid emissions. Under this program, a new electrothermic reduction process was developed to produce blister copper after collecting essentially all of the sulfur by a single-unit operation. The process feasibility was indicated by a laboratory-scale investigation that demonstrated chalcopyrite concentrate can be roasted to less than 1 percent sulfur and that the resulting calcine can be reduced with carbon to blister copper by a cyclic process in a single arc-smelting furnace. Pilot-scale tests in an 800-kV-A electric-arc furnace demonstrated that 98.4 pct of the contained copper can be continuously recovered as metal by operating at bath temperatures between 1,350° and 1,375° C. Smelting rates of approximately 225 lb of blend ft2 of bath surface/hr resulted in power consumptions of approximately 520 kW-hr/ton of blend. The blister copper that was produced contained less than 0.1 pct iron while the precious metals reporting to the copper product and gangue material elimination were similar to those in a conventional smelting operation.

Jan 1, 1976

By Robert G. Lundguist

REAM is a unique and promising method of rock breaking using high energy, inert projectiles to impart mechanical energy to the rock. This paper describes a demonstration of the application of this new technology to two specific problems in open pit mining: secondary breakage and the scaling of loose material from pit walls. Under previous government contracts, Physics International Company developed the projectile impact method for a large variety of commercial and military rock excavation tasks. A 4 meter (13 foot) diameter by 16.8 meters (55 foot) long tunnel was driven at the Hope Valley Mine in the Sierra Nevada mountains of California in 1972 and 1973. An average of 1100 kg (1 ¼ tons) of a 172 MN/m2 (25,000-psi) granodiorite formation was broken by each of 590 shots used to drive the tunnel.l Based on these results it is estimated that REAM can drive over 60 meters (200 feet) of tunnel per day at about 88 percent of the cost of drilling and blasting. In addition, repeated axial impact by high energy projectiles was used to drill a 0.4 meter (16 inch) diameter horizontal hole in the same granodiorite formation. Each shot advanced the hole an average of 0.2 meter (8 inches).

Jan 1, 1976

By Allan Gebhard

The purpose of this paper is to summarize the role of water resource monitoring in mining activities and to discuss the considerations that go into designing and implementing a monitoring program. The design of a monitoring program is invariably based on sound engineering and scientific judgement since no design formulas exist that can be universlly applied to the monitoring of all activities. As discussed in this paper, however, a methodology of designing a water resource monitoring program does exist. In order to cost-effectively monitor the water resource impacts of mining activities, the following three monitoring related items should be understood: 1. the role of water resource monitoring in the planning, construction, and operational stages of mine development, 2. the available water resources monitoring methods and the proper role of each method in the various scages of mine development, and 3. the strategies that should be followed in designing and implementing a water resource monitoring program.

Jan 1, 1976

By D. Laguitton

The basic chemistry of a1•senic related to its dissolution and subsequent precipitation in gold-mine waste waters is discussed. The lime addition methods provides the most economic treatment of arsenical slurries, but requires a careful control of the oxidation of Asm into Asv, of the pH (>12) and the filtration of the precipitate. If arsenic levels below 0.5 mg/ l are required, a modification of the method by phosphate addition must be considered.

Jan 1, 1976