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By Peter Keppler, Charles Jackson

WHY DO AN AUDIT? There is increased enforcement of environmental laws and regulations at State and Federal levels with attendant steep fines and even the possibility of jail sentences. We are all aware of environmental and public health and safety incidences (i.e., Love Canal, Bhopal) which have led to stringent laws and regulations (i.e., CERCLA, RCRA, SARA). In some cases, the courts have specified that a company institute an audit program as a condition of settlement of claims which related to lack of environmental control. The U.S.EPA issued an Environmental Auditing Policy Statement in the November 8, 1985 Federal Register (pp. 46504-46508) which encourages the use of environmental auditing by regulated entities. Elements of what EPA considers to be an effective environmental auditing program are outlined and briefly explained. These factors combine to indicate why there is a growing number of companies which have instituted an audit program. Briefly, the program can and should be used to monitor compliance with environmental regulations and corporate policy, to prevent violations, to improve policies and procedures, to raise the level of environmental awareness, to encourage communication among operations and all management levels about environmental problems, and to measure risks and control costs. AMAX Inc. has had an environmental audit program since the early 1970's. The AMAX Environmental Affairs Department, working with the Law Department, oversees and coordinates environmental audits and analyzes the findings which an audit reveals. Facilities are audited on a regular schedule; those having the greatest potential for environmental liabilities are audited at least annually; other facilities are audited less frequently. The question of who performs the AMAX audits was settled in favor of the audit team being independent of personnel from the facility being surveyed. Other methods of auditing could be the following: - Independent contractor (Appendix A) - Combination of independent contractor and in-house staff - Self-audit by site personnel The merits and demerits of who should conduct the audit can be analyzed to suit your particular needs. Next you need to decide on the procedure for the audit and the form for reporting and follow up. Environmental publications referenced in Appendix B can be helpful to you at this point. After deciding on the form of auditing, a schedule is prepared and followed to the closest extent possible. This schedule should be published and distributed to the sites so facilities know when they are being audited. This is not designed to be "a game of hide and seek." Various elements of the AMAX Audit Program are as follows: Team selection Pre-visit preparation Site visit Exit interview Report Using the audit Follow-up Team Selection The usual make-up of the team is the audit manager, the environmental specialist who normally provides assistance to the site or has knowledge about the operation, and a legal representative if his or her schedule allows. The legal representative will review the findings of the audit team if a personal visit is not timely or necessary. Size of the team can be expanded, but a minimum of the audit manager and the environmental specialist is best. Two sets of observations are better than one. The environmental specialist can also provide the rapport which is beneficial to creating the appropriate tone so that the site people will be as cooperative as possible. This is not to be an antagonistic exercise.

Jan 1, 1991

By W. J. Spat

Political risk is an integral part of the mining business in Northern Andean countries. Peru, Ecuador, Colombia, and Venezuela all have a higher than average political risk compared with other South American countries. Successful operations in such contexts require: 1. Good political risk information; 2. A thoroughgoing political risk management plan; and 3. A strategy to deal with political risk perception on the part of the investing public. Obtaining quality political risk information, developing a political risk management plan, and addressing political risk perception are the foci of this work.

Jan 1, 1999

By Bob Rautenberg, Luminita Calin

The Tunnel and Reservoir Plan (TARP), commonly known as the Deep Tunnel Project, was developed by the Metropolitan Water Reclamation District of Greater Chicago as a two-phase solution to the problem of waterway pollution and basement flooding due to sewer system backups created by the combined sewer overflows. With only one contract left before completion of the Phase I tunnels—the 12.4 km(7.7 mi.) long Little Calumet leg—the pollution control phase of the 175.7 km(109.2 mi.) long system will be 93% complete, once the Torrence Avenue tunnel project comes to an end. This paper describes the Torrence Avenue tunnel project, currently under construction by the joint venture of Kenny (Sponsor) / Kiewit / Shea. Mining of the10.4 km (34,151 feet) long and 8.3 m (27'-4") diameter mainline tunnel was completed in a record thirty-one-weeks period and the concrete lining is nearing completion. Details on the complete muck handling system, numerous mining and concrete lining records will be given.

Jan 1, 2001

By K. J. Reid

With the current trends of increasing costs and decreasing head grades the mineral industry is no longer operating in very high profit areas and has been forced to pay greater attention to the application of modern technology. Although here are many technological advances to the credit of the industry in recent years there are still many processes being operated in the traditional manner and still many areas awaiting the application of methods which have been proven in other industries. Compared with the chemical industry the mineral industry is seriously ageing in the general areas of process analysis and process control, more so than can be justified by the complications arising from having to deal with particulate systems with properties far different from ideal, or even non-ideal, liquid systems. One area in which there has been a remarkable lack of application in the Mineral industry is that of analog computation and the authors feel that there is considerable scope for the use of the analog computer in studying mineral industry processes. The paper outlines the basic principles and features of the analog computer and describes its role as a simulation tool in some engineering and mineral processing systems.

Jan 1, 1972

By Carl G. Hogberg

To the casual observer there is probably no simpler appearing operation in the mineral industry than a limestone quarry. It might seem that the entire operation - from the drilling, blasting, and loading of the stone, its transport to a mill for crushing, washing and sizing, to loading into boats, railroad cars, or trucks for delivery to customers - can be comprehended at a glance. But no first impression could be more misleading. It is one of the purposes of this presentation to sketch the broad outlines of the extensive limestone industry in the United States which, measured in terms of volume of production since the end of World War II, has grown almost 300 per cent to a national level in 1957 of 384 million net tons.1 Another objective will be to discuss in more detail this industry in the State of Michigan. For this latter purpose, the Michigan Limestone Division plants at Calcite and at Cedarville will be used as examples. These descriptions will, we believe, show that the limestone business has complexities to match its size.

Jan 1, 1962

By T. W. Camm

The Bureau of Mines conducts studies of the economic impacts of regulations on federal lands. These studies are part of the Bureau Potential Supply Analysis (PSA) program. To meet the needs of these studies, a methodology was developed to estimate operating and capital costs for a mineral deposit given its tonnage, grade, and depth. The format for the cost models in this study was developed at the Bureau's Western Field Operations Center (WFOC), Spokane, W. A., for studies of known and undiscovered resources on Federal lands. These cost models are described in a Bureau publication by Camm (1991).

Jan 1, 1993

By Jack V. Hill

A unique type of grinding mill liner has been developed by Waagner-Biro A.G. of Austria. This liner system, termed an angular spiral lining (.ESL), was, successfully tested by Magma Copper Company's San Manuel concentrator in both their 10 Ft x 10 Ft (3.05m x 3.05m) and 12 Ft, 6 In x 14 Ft (3.81m x 4.27m) grate discharge wet grinding ball mills. Magma Copper's savings in power and grinding balls justified conversion of more than half of their twenty-six ball mills to the ESL system.1,2 The ASL system was provided by the Capitol Castings Division of Midland Ross Corporation, the exclusive licensee for such conversions. Capitol Castings proposed the following as expected benefits from installation of an ASL system in an 18 Ft x 21 Ft (5.49m x 6.40m) overflow discharge wet grinding ball mill at the Pinto Valley Operation of Cities Service Company: "(a) Reduction of power consumption per ton of ore milled = 12%, (b) Increased throughput = 6%, (c) Reduction of ball consumption = 6%."

Jan 1, 1982

By Wei Victor Liu, Omer Faruk Ugurlu, Chengkai Fan, Bei Jiang

The accurate prediction of truck productivity plays a pivotal role in improving the efficiency and profitability of open-pit mining operations. However, predicting truck productivity is challenging owing to the complex nature of the working conditions of the mine site. This paper proposes a deep neural network model to overcome the challenge of predicting truck productivity in open-pit mines. The prediction model was built using eight variables and was optimized by considering different train-test split ratios, numbers of hidden layers and neurons, and activation functions. The proposed model's performance was evaluated using various metrics and was compared with other commonly used machine learning algorithms. According to the results, the proposed model outperformed traditional machine learning algorithms by achieving higher accuracy and lower error rates, with the best-performing model having four hidden layers with 70 neurons per layer and a scaled exponential linear unit activation function, resulting in a coefficient of determination value of 0.89. This demonstrates the potential of deep neural network models for predicting truck productivity in open-pit mine sites. Moreover, a single variable sensitivity analysis was conducted to investigate the impact of input variables on truck productivity. The results show that haul distance is the most influential variable for the prediction of truck productivity.

Feb 12, 2024

By Jay F. Colinet

Coal workers’ pneumoconiosis (CWP), commonly known as black lung, is caused by the inhalation of respirable coal mine dust and is a disabling and potentially fatal lung disease with no cure. Historically, CWP has taken a tremendous human and financial toll in the US coal mining industry. Recent health surveillance data indicates that CWP continues to occur at elevated levels. Respirable coal dust exposure must be controlled to prevent the development of CWP. The Pittsburgh Mining Research Division of the National Institute for Occupational Safety and Health (NIOSH) conducts laboratory and mine-site research to identify control technologies that can be used to successfully reduce respirable dust levels. Various technologies, using multiple methods of control, can be applied in order to reduce dust levels. An overview ofCWP’s impact and a general methodology for controlling respirable dust in underground coal mines are discussed in this paper.

Jul 30, 2020

By F. G. Rinker

The world demand for metallized iron continues to increase, keeping pace with steelmaking requirements for lower cost hot metal. Virgin iron ore and in-plant oxide fines can be reduced to direct reduced iron (DRI) and hot briquetted iron (RBI). MR&E has developed an improved coal-based process for cost-effective production of either DRI or HBI. Starting with dry compaction, the process combines the latest technology for material preparation, rotary hearth furnace construction and environmental control. Coarse iron ore fines are blended with pulverized non-metallurgical coal to produce a highly metallized (>90%) product. This paper presents production and installation cost data based on operating and under-construction iron oxide reduction facilities.

Jan 1, 1999

By Donald E. Hendrickson

A new prinicple of side dumping front end loading for underground mucking machines has completely changed the concept of underground loading and haulage equipment arrangement both in production and development work loading. Versatility and adaptability of this type of machine permits combinations with a broad range of haulage means not possible with -conventional overhead loaders. Steel "armored" conveyors serving this type of loader are replacing conventional rail mounted car haulage to give a continuous loading operation and effect important economics of reduced manpower, faster loading rates and fewer working areas for a required production. First used in Germany this easy to control and highly efficient means of placing rock from the muck pile on or into haulage means has advanced the art of underground rock loading more in the past three years than any other advancement since the first successful small crawler mounted air powered loader was introduced in 1954. Bucket type loaders with a relative new side dump principle are gaining in popularity for underground loading. They are replacing conventional overhead loaders in present applications and becoming first choice in new ones. Primarily for hard rock development and production loading they are also widely used in production loading of coal and other soft materials. This discussion briefly traces the historical development of hard rock underground loaders to the new side dump type and its present population. In more detail various applications, loading techniques and the advantages of operation, production and economy with the side dumper in hard rock loading will be dealt with.

Jan 1, 1966

By J. Kretschmann, P. Goerke-Mallet, C. Melchers

Mining always leaves a mark behind. Dealing with this legacy is not only a tremendous challenge in Germany, but internationally too. The Technical University Georg Agricola (THGA) in Bochum, Germany, has established a Research Center for Post-Mining. Researchers combine expertise from a variety of technical and nontechnical fields in their quest to shape the post-mining era that completes the mine life cycle. In this respect, the Research Center focuses on four research areas: Perpetual tasks and mine water management, Geomonitoring, Material sciences and site transition. With more than 200 years of successful partnership with the mining industry in Germany and abroad, THGA offers a perfect setting for fresh and sound ideas in order support mining’s social license to operate. The aim of the paper is to describe the Post-Mining Research Center along with exemplary research projects that are of interest to the mining industry globally and to foster technical communication and research networking.

Mar 2, 2022

Table A. Conversion of English to SI Units Table B. Strength Properties of Rocks Table C. Engineering Properties of Rock Table D. Properties of Common Minerals Table E. Material Properties and Characteristics Table F. Heat Value of Various Fuels Table G. Geometrical Relationships and Mensuration Formulas Table H. Standard Sizing and Meshes Table I. Ship Measures Table J. International Atomic Weights Table K. Time Value of Money Factorsfor Discrete Compounding

Jan 1, 2008

By William G. Freeman

In comparison to many mineral commodities, barite has a low unit value. It is mined and sold in low volumes in high-grade (90-98% BaSO4) forms to basically one industry that uses approximately 75% of the free world production. Based upon the above criteria, all factors must be considered in determining if a barite deposit is economical; such as, the type of deposit, mining and milling methods required, transportation to the markets, tariffs, local political conditions, etc. In other words, barite mines are made--not found. The length of this paper precludes any indepth discussion of geology, mining and metallurgy of barite. Most of this information can be found in data already published, such as D. A. Brobst's bulletin1 on the Barite Resources of the United States.

Jan 1, 1971

By Kanhaiya Mishra, Phanil. K. Mandal, S. K. Behera, P. S. Paul, Prashant Singh, C. N. Ghosh

The techno-economic and social benefits of cemented paste backfill (CPB) resulted in its wide acceptance by the mining industry. The Ordinary Portland Cement (OPC) remains the key binder but to diminish its economical constraints, suitability of alternate binders has been examined worldwide. The present study aimed to investigate the effect of partial replacement of OPC with fly ash on the CPB’s strength and to determine the most optimal mix to achieve the required strength (1 MPa at 28 days of curing) at the most cost-effective way using the Bayesian network (BN). The CPB mixes were prepared at 72 wt.% solid concentration with mill tailings (87–91%), OPC (6–13%), and fly ash (0–4%), and instantly after mixing, fresh (slump, bleeding, density) CPB properties were measured. The strength was tested at 7, 14, 28, and 56 days of curing and initially analysed through traditional model. The traditional models follow the aleatory principle and are considered not appropriate for geotechnical engineering. Hence, the BN model was developed and tested. The reliability of two classifiers in learning model structure was compared which gives Naïve Bayes as the highest reliable tool. The CPB’s strength is most sensitive to the OPC content. The most consistent mix(s) is mill tailings: 87–88%, OPC: 9–11%, fly ash: 1–4%. Adding fly ash at 89–91wt% mill tailings possesses high failure probability of the CPB. The collinearity test indicates that the fines percentage and chemical composition of CPB’s ingredients are highly correlated with its slump, bleeding, and strength development.

Jul 14, 2022

By G. A. Munoz

Gold leaching of an auriferous pyrite ore from the Portovelo deposit in Ecuador indicates that noncyanide leaching systems, such as thiocyanate and thiourea, are not as effective as the traditional cyanide system. For example, whereas approximately 95% of the gold can be leached from the ore with cyanide, only about 50% gold dissolution can be achieved with a thiocyanate leaching system. Electrochemical measurements indicate that gold is not cathodically protected by pyrite in these systems. Based on the results of preliminary diagnostic experiments, it appears that gold dissolution in thiocyanate and thiourea systems is limited by passivation due to the formation of either elemental sulfur or sulfur compounds on the gold surface.

Jan 1, 1999

By Yasutaka Izumi, Tuneyoshi Funasaki, Keizou Miki, Makoto Kanai

INTRODUCTION The Tokyo metropolitan region, inclusive of the three neighboring prefectures (Kanagawa, Chiba and Saitama), has the highest concentration of population and industry in Japan; with an area of 13,500 km2 or only 3.6 percent of the national land, but a population of 31.8 million or 26 percent of the national total, and a Gross Regional Product (GRP) of146 trillion yen (US$1.33 trillion) or 36 percent of the overall GDP of Japan as of 1990. Tokyo Bay, embraced by the metropolitan region as shown in Figure 1 (a), (b), is open to the Pacific Ocean as a marine gateway and is ringed by large cities and coastal industrial zones together with port facilities, all constituting a concentration of prime importance for socio-economic activities. The Trans-Tokyo Bay Highway (TTB highway), which crosses Tokyo Bay and provides a direct transportation link between the west and east sides of the bay, has long been a sort of “dream-come-true” project in Japan. As shown in Figure 2, linked to the Tokyo Bay Shore Highway, Metropolitan Inter-city Expressway, Tokyo Outer Ring Road, Tateyama Express-way, and others, it will play an important role as an integral part of the regional highway network to help promote spatial redistribution and multi polarization of urban functions, thus strengthening cooperation between cities and restructuring the metropolitan region. The TTB Highway is a project of 15.1 km in length designed as a toll highway to cross the bay by tunnel and bridge, and will require ten years to complete at a total cost of more than 1,438 billion yen (US$13.077 billion). Following more than 20 years of feasibility and environmental assessment studies, construction of this giant offshore highway project commenced in May 1989 as the first large-scale highway project with private-sector participation under the prevailing Road Law in Japan, and is now steadily proceeding toward the goal of completion in fiscal1997. This report outlines the entire TTB Highway project, including the waterproofing measures against high water pressure and the rapid construction method applied in the construction of shield tunnel sections.

Jan 1, 1997

By K. Rajamani

The word adapt means "to change so that one's behavior will conform to new or changed circumstances." Applying this definition to process controllers suggests that an adaptive controller can change its behavior in response to changes in the dynamics and disturbances of the process. In the minerals industry there are many control cases where adaptive control will provide superior control as compared with more traditional PID (proportional, integral, derivative) control. A typical plant uses as many as 100 to 200 control loops for lprocess regulation. Therefore, the task of initially tuning and then periodically retuning these controllers is a formidable problem, During the time the controllers are "un-tuned", product quality may deteriorate and unstable operations may result. Adaptive controllers are capable of tuning themselves, thus avoiding this problem. The computers commonly used in distributed control systems are easily capable of implementing adaptive controllers. In addition to the possibility of using the control computer to implement adaptive controllers, many distributed control systems will offer adaptive control as a standard feature in the near future.

Jan 1, 1984

By S. Makni, R. E. McIvor

Grate discharges historically outnumbered the overflow type of industrial wet ball mills. However, overflow discharge mills now strongly dominate. In order to understand their comparative advantages and disadvantages, Corem carried out a broad review of this topic. Where the data made it possible, the Functional Performance Equation was used to separate circuit classification from mill grinding effects. Batch tests were conducted in a torque-metered mill at different slurry levels. This paper presents the outcome of these investigations, which is a very strong case for the industry to once again consider grate discharges.

Feb 1, 2023

By Siddhartha Roy, Hemant Agrawal, Ram Madhab Bhattacharjee, Devi Prasad Mishra

Heat stress is a major concern for the health, safety and productivity of miners working in hot and humid underground mines. At greater depth, heat inside underground mines increases due to geothermal gradient, heat released from high-capacity machinery, exposed rock surface, auto-compression of air, human metabolism, etc. Prolonged physical work in thermal environments severely affects the health, safety and efficiency of miners. In order to address this important issue, a systematic literature review (SLR) has been conducted. This SLR aimed to identify the research gap in the area of heat stress effect on underground miners and its control. An extensive literature search was carried out on numerous digital databases, grey literature and conference proceedings to identify relevant research work for this review. Moreover, the impactful studies, methodologies and preventive measures undertaken during the past five decades on the effect of heat stress on underground miners were retrospectively analysed, with a broader aim to explore the need for further research on this pertinent topic. Overall, 571 references were identified from the literature review, out of which 51 research articles addressing the sources of heat, heat stress effects on miners, heat stress indices and control measures for heat stress in underground mines were selected as primary papers for detailed review. Pre-developed fatigue is one of the prime causes of health hazard, safety and productivity loss of miners working in underground high heat stress zones. Hence, development of a better heat stress index integrating personal, environmental parameters and pre-developed fatigue (PDF) of miners is essential.

Jan 14, 2022