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By Watters R

Modem open cut and underground mining in the tropics inevitably expose partially weathered and unweathered rocks to oxygen and water, leading to weathering and the release of solutes and often acidity as well. Historical monitoring data can demonstrate these phenomena. Three case studies from open cut mines in the north of the Northern Territory illustrate the deterioration in quality of pond water receiving drainage from waste rock dumps. The potential for deterioration of water quality was not recognised in many mine Environmental Impact Statements prepared and accepted in the 1980s. The examples documented indicate the importance of adequately planning for this near inevitable process. Retrofitting a mine water management system to 'no' or minimal release can be very difficult and expensive, and may not be feasible, leading to downstream pollution. The characterisation of acid and solute production potential of ore and waste rock, and improved dumping strategies and water management are very important to minimise the environmental impact of mining in the tropics.

Jan 1, 1994

By A. S. Rhea

SALT-WATER disposal in the East Texas field by means of injection into the Woodbine sand is a relatively new procedure. The purpose of this paper is to present what has been accomplished to date in this field, with-out detailed discussion of other means of disposal, such as surface impound-ing for evaporation or release into surface streams. Subsurface disposal of salt water is still in an experimental stage in the East Texas field, and, though water can be injected into the Woodbine sand, the economic problem is not as yet solved. As past experience has been that fields producing from the Woodbine formation produce large quantities of salt water, it was assumed early in development of East Texas that it would be necessary to dispose of a tremendous quantity of salt water in the later periods of production. There has been a gradual increase in the amount of salt water pro-duced in the field, until at present it is about 200,000 bbl. per day from approximately 4400 wells. It is only natural to expect an increase in the number of wells producing water, as well as the amount of water produced in the future, and it has been estimated that if present practices con-tinue the production of salt water may ultimately be as much as 700,-000 bbl. per day. The Woodbine sand is found in the East Texas field at an average depth of 3650 ft. The oil-bearing portion of the sand lies between the depths of 3050 ft. below sea level, on the east edge of the field, and 3320 ft. below sea level on the west, which depth was the estimated original average oil-water contact. The Woodbine sand under the field has the form of a broad tilted wedge pinching out on the eastern side of the field and dipping gently into the East Texas Basin toward the west. The Woodbine sand in the East Texas field has an average porosity of approximately 25 per cent and is highly permeable, the average being about 1300 millidarcys.

Jan 1, 1940

By W. C. Muehlhof, L. D. Lamont

THROUGHOUT the anthracite industry's history, the problem of handling and dis¬posing of refuse material has been one of major importance. In the early days of the industry's activities, only the large sizes of anthracite were satisfactory for market requirements and the smaller sizes were deposited as refuse. As time went by, more efficient coal-burning equipment was developed and a market demand was created for the finer sizes of coal. This demand made it possible to recover market¬able coal from banks deposited as refuse in the earlier days of mining. The same condition holds good today and we can see a definite trend toward the objective of utilizing the No. 4 and No. 5 buckwheat sizes. Under present conditions, we know that a limited market exists for No. 4 and 5 buckwheat; we know that the finer sizes of anthracite can be burned as pulverized fuel; we know that these fine sizes can be processed and sold as bri¬quettes, and we also know that the heat content of these fine sizes of coal is compar¬able with that of the sizes now merchan¬dized. Therefore, it should be the objective of the industry to conserve these fine sizes of coal in such manner that if and when processing facilities are developed, and market demands exist, the material can be salvaged and made available to meet these demands. From the standpoint of economical future reclamation, the ideal method of disposing of refuse containing the finer sizes of coal is to deposit it in banks separate and apart from other breaker refuse. By this procedure, the minimum amount of material will be processed in future salvage operations to recover the No. 4 and No. 5 buckwheat sizes. Many collieries in the anthracite region are operated under leases that have a specific term. These lease agreements provide that, upon expiration of the lease by term, exhaustion or otherwise, the ownership of the refuse material reverts to the lessor. Therefore, a question was raised in the minds of these operators: Why should I assume the expense of such pro¬cedure when I have no assurance that I will benefit by the future processing and sale of these fine sizes? Under present conditions, the answer to this question is not one of choice but of necessity, as restrictions imposed by legislation make it mandatory on operators of preparation plants to take necessary steps to properly treat silt-laden waters before permitting them to enter the streams. By reason of these restrictions, the disposal of fine sizes becomes a secondary_ rather than a primary operating con sideration, and the procedure for disposing of this refuse becomes a matter of choice governed principally by topographical and geographical conditions. METHODS OF HANDLING REFUSE There are three principal methods of handling and disposing of fine-size refuse; namely :

Jan 1, 1946

By Paul D. Bybee

The Freeport Sulphur Company operates four sulphur mines in the coastal marsh area-03 South Louisiana. Employing the Frasch process of mining, approximately 13-million gallons of water per day is heated to a mining temperature of 325°F and is injected into the sulphur bearing formations of the four mines. A volume of cold waste water, roughly equal to the Input, is removed from the formations and presents a disposal problem. Two additional mines are currently being developed and will increase the disposal volume by an additional 5-million gallons per day. Although these properties are in a relatively small area, geographically speaking, as shown in Figure 1, they each represent a separate disposal problem with the treatment methods designed for the individual mine.

Jan 1, 1959

By Zbigniew Smieszek, Ryszard Chamer, Ryszard Prajsnar, Zygmunt Kurek

"Lead-containing wastes processed at the IMN’s Division in Legnica originate mainly from dry and wet dedusting installations of the technological lines for copper production. These are lead dusts and lead-zinc dusts characterised by the specific properties resulting from the chemical composition of the Polish copper concentrates. Besides lead, they contain many accompanying metals and impurities such as zinc, copper, sulfur, chlorine, potassium, sodium, and also bituminous substances. Processing of lead-containing dusts is conducted in the installations of rotary-rocking furnaces heated with gas-oxygen burners fitted with auxiliary systems for cleaning process gases and refining re-circulating dusts. The processing technology utilizes innovative process and technical solutions enabling disposal of lead-containing wastes from copper metallurgy and from non-ferrous metals industry according to the BAT recommendations and to the guidelines specified in integrated permission. In this paper, the main technological aspects of processing lead-containing dusts at the IMN’s Division in Legnica have been presented.IntroductionCrude lead is obtained in Polish lead metallurgy from various primary and secondary materials, such as Zn-Pb concentrates, lead-bearing dusts of copper metallurgy and battery scrap. In zinc smelter Miasteczko Slaskie S.A. crude lead is produced from sulfide and oxide Pb-Zn concentrates in ISP process. Orzel Bialy S.A. and Baterpol Ltd. produce crude lead in short rotary furnaces in the process of smelting products of mechanical battery scrap separation– desulfurised or not desulfurised paste and metallic fraction. KGHM Polska Miedz S.A. and IMN Divison in Legnica produce crude lead in rotary furnaces in the process of smelting of polymetallic dusts and slimes from copper production processes."

Jan 1, 2008

By Hideki Yamamoto, Junji Shibata

"The chemical reactions of fluoride and chloride gases with metal chloride or metal oxide are utilized as an effective treatment for harmless disposal. These chemical reactions can be adopted in the temperature range of 80°C~400°C, which is lower than that in the combustion treatment (800°C). Reaction products are metal fluoride or metal chloride which are a harmless and a valuable chemical material as one of new resources. This paper, concerns with a new harmless disposal treatment of toxic global warming gases.IntroductionNew technology to make fluoride and chloride gases such as NF3, CF4, SF6 BF3, Cl2 and BCl3 harmless has been developed and a new concept on the removing toxic gas to be used in the advanced process of materials has been established. The fluoride gases ~re toxic and special type of gases to be used in the process of manufacturing semiconductors and their specific applications include the dry etching of semiconductors, cleaning of CVD systems, an oxidation agent for rocket fuel etc. Especially, NF3 is also attracting an attention as a high-energy source for chemical laser systems. As a fluoride gas like NF3 is, however; toxic and highly stable chemically, if discharged into the atmosphere, it is liable to cause far-reaching adverse influences on global warming in the same manner as carbon dioxide gas and feron gas.Up till now, the combustion treatment method has been adopted for the disposal of the gas, and when treating the gas by high-temperature combustion (800""C), the generation of nitrogen oxides (NOx), sulfur oxides (SOx) and hydrogen fluoride (HF) have been confirmed: These chemical substances are not only linked with an intense c0rrosion of the combustion systems but also create the generation of atmospheric pollution and acid rains, and therefore, constitute a serious social issue."

Jan 1, 2000

By Hideki Yamamoto

A new technology to convert fluoride gas (C2H2F4 : R-134a) contained in the exhaust gases from semiconductor manufacturing plants and refrigerators directly into a harmless substance have been established, thus, presenting a new concept for the disposal of fluoride gases such as CFCs that are associated with the global warming. Experimental results verify that chemical reactions with metal compounds can take place at substantially lower temperatures of 700- 800K as compared with combustion treatment temperatures of 1200-1500K. The reaction product is mainly metal fluoride, which chemically is a harmless material. Furthermore, this process is compact, easily controlled, safe and has low running costs. This paper deals with a new chemical reaction method for the harmless disposal of gases effecting the global warming.

Jan 1, 2003

By Hideki Yamamoto

A new technology to convert fluoride gas (C2H2F4 ; R-134a) contained in the exhaust gases from semiconductor manufacturing plants and refrigerators directly into a harmless substance have been established, thus, presenting a new concept for the disposal of fluoride gases such as CFCs that are associated with the global warming. Experimental results verify that chemical reactions with metal compounds can take place at substantially lower temperatures of 700- 800K as compared with combustion. treatment temperatures of 1200-1500K. The reaction product is mainly metal fluoride, which chemically is a harmless material. Furthermore, this process is compact, easily controlled, safe and has low running costs. This paper deals with a new chemical reaction method for the harmless disposal of gases effecting the global warming.

Jan 1, 2003

By V. Steve Reed, Ed L. Reed

The in situ leach mining process generates a waste stream that is high in sulfates, total dissolved solids, and radium 226. During the mining phase, the volume of the waste stream is relatively low and consists primarily of the bleed stream. During the restoration phase, larger volumes of waste water are generated. These waste streams require environrnentally sound disposal. The low net evaporation rate in the Coastal Bend area precludes pond evaporation as a feasible disposal alternative. Reverse osmosis is a practical method of reducing the volume of the waste water handled, but the concentrated waste stream from the reverse osmosis unit must be disposed properly. Deep well injection into highly saline reservoirs is considered a sound method of disposing of the liquid waste generated by in situ mining in the Gulf Coast uranium district. Thirteen injection wells have been permitted to serve the disposal needs of the leach mining industry in Texas. Of these 13, 11 have actually been drilled. Seven applications are pending. The injection zones for the permitted wells range from depths of 3050 to 6200 feet. Pressure limitations imposed on these wells range from 500 psi to 1350 psi. The following criteria are used to determine the desirability of a disposal well site: 1. A minimal number of nearby, improperly plugged borings which penetrate the disposal zone; 2. Minimal crustal disturbance; 3. Sufficient salinity of the water contained in the disposal zone; 4. Protection of oil and gas producing zones; and 5. Sand of sufficient permeability and areal extent to handle the desired volume without fracturing the reservoir. 1. Improperly plugged borings: During the early part of the century, oil wells, gas wells and test holes were drilled using cable tool equipment, often with a minimum amount of surface casing. Production casing, when it was set, was often partly removed when the holes were abandoned. Thus, wells drilled prior to 1940 frequently have less than 100 feet of surface casing and either no production casing or the upper part of the production casing removed. Additionally, these holes are often plugged only with mud. The close proximity of these holes to an injection well location are a concern in that they can provide an avenue for injection-depth fluids to migrate up the bore hole and jeopardize shallower fresh water reservoirs. Usually, where there are more than 6 or 8 poorly plugged borings in a 2 1/2 mile radius of the well site, it is preferable to examine deeper zones for disposal well potential. The deeper zones are especially attractive where the borings are not in a cluster, which renders monitoring more difficult. Often, even the deeper disposal zones are penetrated by a few improperly plugged borings. When this condition arises, the potential for leakage through the borings can be addressed in the following ways. a. Demonstration that the static head in the boring is higher than the anticipated increase in bottom hole pressure generated at the boring by the disposal well. A 100 psi differential between these two pressures is recommended. The calculated increased pressure at a boring caused by injection should be refined using annual bottom hole pressure measurements in the disposal well. Figure 1 illustrates an injection pressure map which can be overlain on the oil well map to determine the anticipated increase in pressure expected at each oil, gas or abandoned hole. b. Shallow ground water monitoring. A shallow monitor well is drilled next to the boring and both pressure and quality measurements are made periodically in the shallow well. c. Disposal zone monitoring. Recently there has been a tendency for regulators to require disposal depth monitor wells instead of shallow well monitoring. We consider disposal depth monitoring to be a less effective method of monitoring because it provides only indirect evidence of potential problems. Assumptions have to be made for the unplugged borings, such as mud weight, that are not addressed by the disposal zone monitoring program. There is little improvement with this system to that discussed in "a" above. A shallow zone monitoring program, however, yields direct evidence of a developing problem with an unplugged boring. Leakage by the boring will be detected quickly by an abnormal increase in pressure in the shallow well. Quality monitoring will detect upward migration of poor quality fluids. The pressure data provide an early warning of impending leakage; the quality monitoring will detect actual fluid migration.

Jan 1, 1980

By J. L. Wright

When management is confronted with the risk of constructing a waste disposal well, these are some of the questions which may arise. Should the company expand the present waste treatment plant? More lagoons will cut into valuable acreage which might be needed later, and yet the pollution engineer says he can guarantee results. On the other hand, does the formation being used for those successful disposal wells off to the west extend over far enough to be used for the company's own well? Will the formation be thick enough? Will it be too deep? Will it be porous and permeable enough? Apart from needing to make a profit on the products made at the plant, plant officials must sometimes act under pressure to comply with pollution standards. The manager must build the cost of the pollution control system into the price of the products made by the company.

Jan 1, 1970

By Fernando Bermejo

El presente trabajo describe la construcción del último depósito de relaves, así como la capacidad y duración del depósito actual y el cálculo de la inversión en la ejecución de la berma inicial del depósito de Santa Catalina. En este sentido, el objetivo del texto es cumplir con las disposiciones gubernamentales para la disposición de relaves, así como evitar la contaminación del agua y los terrenos de cultivo.

Oct 14, 1980

By Sergio Samuel Sarmiento Sobrino

Dado que toda actividad minera genera relaves -en tanto son altas concentraciones de químicos y elementos que alteran el medio ambiente- estos deben ser transportados y almacenados en «tanques o pozas de relaves» donde lentamente los contaminantes se vayan decantando en el fondo y se pueda recuperar el agua. En ese sentido, el presente texto señala el manejo de relaves compactados en el depósito de Ramahuaycco, a través de desaguar los tóxicos antes de ser depositados. Así, los relaves filtrados son primero espesados y luego filtrados para el contenido de agua adecuado para su disposición. Por razones de estabilidad, los relaves filtrados requieren ser compactados a través de la desecación de relaves in situ.

Aug 1, 2015

By Eli Robinsky

La disposición de relaves es importante en tanto busca proteger y rehabilitarlo el medio ambiente a un menor costo posible. En ese sentido, el presente texto describe el método de descarga densificada como el más adecuado puesto que logra una solución más aceptable desde la perspectiva ecológica. El método ofrece la ventaja de aumentar la capacidad de las zonas existentes para el almacenamiento de los relaves, sin requerir de la ampliación de las presas perimetrales.

Sep 1, 1983

By Emmanuel Pornillos

Dado que en el Perú, la actividad minera utiliza el minado subterráneo para la explotación de minerales, se revalúa el uso de estos en pasta cementada para el relleno de las labores subterráneas, así como los relaves desaguados para su disposición superficial. En ese sentido, el presente texto señala las experiencias de diseño y operacionales de sistemas múltiples para la aplicación de relaves en superficie y subterráneo en el Perú, de forma que se pueda optimizar la selección de equipamiento y una operación robusta.

Sep 1, 2013

By Emilio Acciarito Filho

O presente dispositivo, tem como objetivo promover de modo contínuo e automatizado a remoção do cascão incandescente aderido nas superfícies das lanças de injeção de oxigênio e gases inertes utilizadas nos processos dos convertedores LD. Constituído de um conjunto mecânico de ferramentas de remoção, posicionadas em um suporte articulado bi partido e simétrico, acionados por cilindros pneumáticos e interligados ao sistema computorizado (PLC) do carro de movimentação vertical das lanças via sensores indutivos de posição; Resultando na maximização das utilizações dessas lanças e consequente aumento da produtividade, com redução de custo e maior segurança operacional nos processos LD.

Aug 16, 2017

By Ingvar Bergqvist

Para activar la carga de explosivos de una manera controlada, se requiere una clase de dispositivos de detonación. En ese sentido, el texto señala la aplicación de estos dispositivos con las medidas de seguridad necesarias para ser aceptados dentro de la actividad minera. Los dispositivos se dividen: sistemas eléctricos y no eléctricos. Entre los criterios de seguridad tenemos: confiabilidad, menor riesgo de detonación prematura, conexión simple y racional, calidad pareja y la adaptación a explosivos disponibles, máquinas de voladura, como de los requisitos del mercado con referencia al tipo de trabajos, profundidades de taladro, etc.

May 1, 1977

The arbitration process, and its drawbacks: Any time you have taken part in a major arbitration, and the decision, when it comes out, is not what you thought it would be (which is bound to happen occasionally), the normal reaction is something like æthe arbitrator got it wrongÆ. Again normally, when you have cooled down a bit, and you look in more detail at the decision, you can see, probably, æwhere he got it wrongÆ (it is only male arbitrators who get it wrong). Ultimately, when reason prevails, and you reflect on it, you can see that what really happened was that you failed to get the arbitrator to see what you were getting at in the point or points concerned. This is doubly frustrating, when you consider what has been involved in getting to this point, having been through it all at least twice. An alternative to this process may be the dispute review board.

Jan 1, 1999

By Robert M. Matyas, P. E. Sperry, Robert J. Smith, A. A. Mathews

INTRODUCTION The first Dispute Review Board (DRB) was utilized on a tunnel project 20 years ago. Increasingly utilized on a wide range of construction projects, DRB's are becoming the norm on tunnel and underground projects. This paper summarizes the growth in this usage, uses observations and experience to establish that barriers to the utilization of DRB's are more perceived than real and that many arguments against the DRB concept are not valid, and notes some of the salient elements that should be considered in practice to optimize DRB effectiveness. The purpose of the paper is to provide an annotated checklist for current and prospective users. The basic concept, structure, and operation of DRB's are described elsewhere and will not be repeated here (ASCE, 1991). DISPUTE REVIEW BOARD USAGE A compilation of Dispute Review Board usage for tunnel and underground projects to January 1994 indicated use on 63 contracts with a cumulative construction value of $3.8 billion and a total of 60 disputes settled. As of that same date, DRB's were planned for another 63 contracts with an estimated construction value of $4.7 billion. (A listing of these 126 projects is available from the authors.) This success and popularity have spread to other civil projects as well as process and building construction. The increase in DRB usage has been exponential. See Figure 1.

Jan 1, 1995

By James F. Holzbach

Although Disputes Review Boards have been used for some time, they had not received wide publicity at the time Monroe County first used one. Public owners frequently resist adopting new contracting practices. This paper discusses an owner's experience with Dispute Review Boards, from learning about them to their use on two (2) projects. The experiences of potential and actual contractor claims are compared to a claim on an earlier contract and the ensuing litigation. Suggestions for possible use for Owner-Engineer disputes and recommendations for use are provided.

Jan 1, 1995

By Jack Eloranta

"Unwanted, dynamic interaction of adjacent blastholes is a well-recognized phenomenon. Timingschemes and products are selected to minimize adverse effects. Large diameter, surface blasting is less prone to dead pressing and other disruptions which commonly plague underground and construction blasters. However, several lines of evidence suggest that fragmentation may be compromised as a result of powder column disruption in large diameter shooting as well."

Jan 1, 2016