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By Erica McGlynn, Brian Negrea, Lance Jackson

There was no need for the people of Cleveland to ask “Where does the raw sewage go? We want to know!” because it was clear. The raw sewage was being discharged into Lake Erie during heavy rainfall events due to the outdated design of the combined sewer system. In efforts to resolve this ongoing issue for the City of Cleveland, the Northeast Ohio Regional Sewer District developed Project Clean Lake in collaboration with the US EPA. Project Clean Lake is a 25-year, $3 billion program consisting of seven large-diameter CSO storage tunnels to be constructed beneath the city’s existing infrastructure. The first four tunnels have been completed using traditional hard rock TBM excavation methods. The fifth tunnel, the Shoreline Storage Tunnel Project, presents unique challenges and complexities as it will be the first large-diameter EPB TBM to dig under the City of Cleveland. The project itself consists of one tunnel drive 14,100' (2.7 miles) in length, two pipe jacking tunnels, three large slurry wall shafts, two diversion structures, and three regulator reconstructions. Upon completion of the project, 12 permitted CSO locations along Lake Erie will be taken offline, reducing overflow volumes by approximately 350 million gallons per year. This paper will discuss the current status of construction and the chosen means and methods, including the myriad of nuanced differences between hard rock and EPB TBM tunneling methods. Particular attention will be given to the site preparation, setup, and organization; TBM assembly; and TBM launching practices.

Jun 13, 2023

By D. Caiden, C. S. Covil, P. J. Chamley

The paper describes the background to alternative delivery models, drawing on international experience, and introduces Project Alliancing/Contract Partnering, common risks and risk sharing on tunnel projects. A plea for early contractor involvement in design is made before describing some whole life design implications for tunnels. The paper concludes with four short case studies; Channel Tunnel Rail Link in the UK, Hull Waste Water Tunnel in the UK; Island West Sewage Transfer Station in Hong Kong, and the New Southern Railway in Australia.

Jan 1, 2005

By Michael Feroz

Severe drought in the Colorado River Basin over the past 10 years has caused water levels to drop in Lake Mead by more than 113 feet. The current lake level is at elevation 1,112 feet mean sea level (msl). Lake Mead is the primary source of water supply for greater Las Vegas. Water for Las Vegas from Lake Mead is accessed through two existing submerged intake shaft and tunnel systems. If the water levels continue to drop in the lake, the Intake No. 1 will become inoperable below water level elevation of 1,050 feet msl. To sustain the current levels of water delivery to all member agen-cies in the southern Nevada region, the Southern Nevada Water Authority (SNWA) has decided to construct a third intake at a deeper depth in the lake to ensure better quality water and enhanced reliability.

By David A. Milligan, William Cobb

2.1 INTRODUCTION This chapter provides the reader with a sense of how a heap leach project may make an orderly, and hopefully non-traumatic, transition from discovery or acquisition to project construction. In making this transition a project can pass through several project development phases (i.e. ore definition and delineation, conceptual engineering, detailed engineering, and ultimately on to project construction and operation). "Go" or "no go" decisions may occur at any point in each of these phases. The transition from ore definition to detailed engineering should be accomplished via a well thought out program of interdisciplinary studies and an integrated, interdisciplinary project team. This chapter also describes, in general terms, a "roadmap" approach to the project evaluation process that must occur as project planning and development progress. It is the experience of the authors, as well as a myriad of companies who have been through the heap leach project development process, that a systematic approach will save many headaches, and many dollars. In fact, it is safe to say that a project with no formalized system of "objectives setting" and "milestone charting" may well flounder along the way, even if an economic ore body exists. Many papers and technical articles have been written about various aspects of mineral resource appraisal, economic evaluation, and mine development. Most of these invoke the same general philosophy of a systematic approach to project evaluation and development, although methods cited for attaining goals are quite variable. This is undoubtedly appropriate, given the fact that there is great variation in approach to project development (e.g., climatic considerations, ore body size and physical ore characteristics, permitting constraints, etc.). For the purposes of this chapter, two primary sources of information have been used to highlight the "road map" approach previously alluded to. These sources are cited throughout the text as Mackenzie (1980) and Snow and Michel s (1986). A brief summary of each of these sources is provided below: Brian GJ. Mackenzie of Queens University (Mackenzie, 1980) has developed a wealth of information concerning project development topics. Much of this information is synthesized in his notes for a short course entitled : "Mineral Exploration Planning and Economic

Jan 1, 1988

By Wi11iam I. Rau

In the recent past, there have been numerous projections of the capital requirements for additional mine and processing capacities required to meet projected non-Communist World demand for minerals during the next 15 years. A consensus judgment would place this currently at $14 billion per year, with the largest expenditures required for increases in aluminum and copper production. Until the early 1960's, internally-generated funds were used to finance nearly all of the large mining companies' capital requirements. Since that time, however, the enormous rise in capital costs per ton of capacity, accompanied by a relative stagnation in the financial condition of many of the major mining companies, have caused the industry to begin to rely on external sources for financing expansion, most notably, project financing from commercial banks and institutional lenders. Seven years ago, it was estimated that, in the five-year period 1972-1976,75% of the total capital requirements of $10 billion per year would come from internally-generated funds, with the balance to be provided by external sources. l There is little doubt that, in the coming decade, the percentage provided by external sources will increase. There should be little difficulty in attracting the necessary investment within the U.S., particularly in view of the expected continuation of companies in diverse industries seeking mineral investment opportunities. The more serious question lies in the availability of internal and external sources of funds for the expansion of mine and smelting capacity in the developing countries. Recently, R. F. Mikesell projected an average annual investment of $4.7 billion (in 1977 prices) over the 1977-1990 period would be required from foreign sources to expand metal producing capacity in developing countries. Mikesell concluded that external financing of mining projects in the developing world has averaged less than $1 billion per year over the past five years, thereby requiring more than a quadru1ling of this financing over the next decade.

Jan 1, 1978

By B. Morris

This presentation will describe the process by which the Quebrada Blanca (QB) copper project in northern Chile was financed. It will also show how a relatively junior mining company addressed the problems created by its inability to provide its share of the equity funding and the guarantees required by the project lenders. QB is located in the semi-arid Andean highlands of northern Chile, 170 kilometres southeast of the port of Iquique and 30 kilometres west of the border with Bolivia, at an altitude of about 4,300 metres (14,000 feet). Figure 1 depicts the project's location. The QB orebody is a secondarily enriched porphyry copper deposit containing reserves of 85 million metric tons grading 1.3 percent copper. Underlying the enriched zone is a significant primary ore zone containing several hundred million metric tons grading about 0.5 percent copper. In the late seventies and early eighties Falconbridge and its affiliates spent $20-30 million dollars exploring the deposit and conducting feasibility studies. For a variety of reasons they decided not to develop the property which was returned to its owners, Empresa Nacional de Mineria (ENAMI), which is a Chilean state mining corporation. In 1988 ENAMI announced its intention to privatize the property through a public bidding procedure.

Jan 1, 1993

By Gregory A. Hahn

Explorationists and engineers rarely speak the same language. Explorationists are not cognizant of the information that engineers require to make the appropriate choices and decisions. Engineers can- not "translate"geo1ogic parlance and data into information relevant to proper decision making. This often creates a physical and intellectual "rift" between engineers and geologists that inhibits a smooth transition to development. A transition team leader who is grounded in both disciplines can best facilitate integration and communications between the explorationists, who understand the intrinsic attributes of a given deposit, and the engineers, who have to design for extraction and beneficiation of an orebody.

Jan 1, 2001

By W. R. Hibbard

Emerging from discussions of U.S. energy policy: from the Project Independence Blueprint; from President Ford's statements to Congress; and from several independent appraisals of the situation; there is a clear objective to achieve an appropriate balance of supply and demand in the near term future (1) by developing more efficient ways of using energy and (2) by extending domestic sources of energy. More specifically, the strategy for achieving this goal has three parts (1) Conservation of energy through greater efficiencies in automobiles, appliances, lighting, heating, and industrial processes. (2) Increased domestic production of oil and gas through new sources such as the outer continental shelf and new efficiencies such as tertiary recovery. (3) Substitution of coal and uranium for oil and gas in utility power plants and industrial heating. The goal of energy research and development is to help achieve these goals and to help minimize the economic, environmental and social impact of our shift from imported energy to domestic sources. The focus of this paper is the implications of the expanded use of coal, and the research and development which may help achieve the above goals in so far as coal is concerned.

Jan 1, 1975

By R. J. Hickson

From 1993 through 1999 Cyprus Amax Minerals Company successfully completed eight major construction projects around the world. Six greenfield mines were brought into production, an ongoing operation was completely modernized, and an environmental issue was appropriately remediated. The projects stretched over three continents, from arctic Russia to the Atacama Desert, from 16,000feet to sea level, from city suburbs to remote wilderness, from a low of $130 million to over $1 billion. Open pit and underground; mill and leach; gold, copper, molybdenum, and coal were all encompassed. The breadth of diversity experience from these projects inspired Cyprus Amax to create a “best practices” project management protocol, to steer corporate expansion into the next millenium. This paper summarizes those best practices, while high-lighting project management pitfalls to avoid.

Jan 1, 2000

By R. J. Hickson

From 1993 through 1999, Cyprus Amax Minerals successfully completed eight major construction projects around the world. Six greenfield mines were brought into production, an ongoing operation was completely modernized and an environmental issue was appropriately remediated. The projects stretched over three continents: from arctic Russia to the Atacama Desert, from sea level to an elevation of 4,900 m (16,00Oft), from city suburbs to remote wilderness and from a low of US$130 million to more than US$ 1billion. The operations included open-pit and underground mines, mill and leach facilities and involved gold, copper, molybdenum and coal. The diversity of these projects inspired Cyprus Amax to create a "best-practices” project-management protocol to steer corporate expansion in the new millennium. This paper summarizes these best practices, while highlighting the project-management pirfalls to avoid.

Jan 1, 2000

By P. Tanaskovic

This is presentation of a model which simplifies application of project management in control of the construction procedure of industrial units (mines, power stations etc). The model is made for further referrence of investors. The most demanding problem in large units is to find the best way of locating all activities within a network. The model uses term "line" (which refers to a construction unit) for a serie of activities which are to be sequentially executed (up to 1000 lines, each with 10-20 activities). The lines are coded in advance. Each line is described by a competent expert. Team of experts provide liason between lines on the basis of computer drawings. The method proved to be extremely effective. In order to provide smooth monitoring at all management levels, graphic documentation is given at 4 levels. The initial level is the third one, made based on input data (more than lo listings per one drawing). By condensation of activities along one line, another level is obtainable. Grouping of lines gives the first level (1-2 listing) for the highest management level. More detailed information is given for a limited (shorter) period at the forth level for the purposes of operational management. Each activity has three phases: prior to contracting, post contracting and accomplishment. All phases are presented at all levels, which enables investor to be continually well informed about construction advancement. Model is written in FORTRAN language. Programs comprise: maintenance of data base, calculation of time and costs and elaboration of graphic and other documentation.

Jan 1, 1986

By J. Herhold, S. Plaum

"Current and future operational processes in the mining and underground construction sector are under the influence of the prevalent competition and the acute necessity of optimization approaches concerning corporate and project processes. Besides general construction procedures, especially underground construction procedures and procedures in the field of deep shaft construction are high-profile. Those processes describe high technical challenges as well as increased requirements to occupational safety and health. Therefor an occupational safety management, which should be adjustable to the company itself and adaptable to all kinds of projects, shall be created. The creation of such an occupational safety management would lead to an economically optimized and safe (within the scope of OSH law) implementation of internal activities for the performance of construction services underground and in the field of deep shaft construction. With this approach the satisfaction of the high safety request as well as the demand for process optimization, as part of keeping the own competitiveness, will be satisfied successfully at once. PROJECT BACKGROUND Introduction The health and safety protection as well as occupational safety look back on a long historical development, which had brought more important sectors and developments during the last years, not only in Germany but also on the European and international level. The accident insurance protected by law has already been reported in 1884, which is astonishing early. The launch time point is strongly connected with the on-going economic development in the end of the 18th century, but above all this increased in the 19th century. The progress of occupational safety and especially the interest in the integration and the concentrated consideration of occupational safety and the health and safety protection in the company process is strongly visible during the 19th century and directly connected to the industrial revolution. [9] The industrial revolution and with that the development of work places lead to changing demands in the field occupational safety and health and safety protection. Insufficient security precautions caused problems in the industrial revolution, such as personnel and material losses as well as serious injuries and their consequences. These and the fundamental economic endeavours of the entrepreneurs lead therefore to the important step to develop an occupational safety system. [9] The prevailing basic ideas seize the insufficient security precaution of work places as well as the economical and profitable ideas of the entrepreneurs and bring them together. From this the necessary entrepreneur’s task comes into being and that is bringing the work conditions to the way that life and health of employees are not in danger. [9]"

Jan 1, 2017

By J. Herhold, S. Plaum

"Increasing worldwide energy demands, coupled with desires for cleaner energy, have led to greater research of renewable energies. Strongly weather-dependent energy sources, e.g. solar and wind energy, are unable to provide a constant control energy to withstand the fluctuation of the extensive power systems during peak hours. The pump storage plant Nant de Drance in Switzerland will not only have the capacity of a nuclear power plant, producing 900 MW, but will also combine the environmental aspect and the demand for controlled energy. Nant de Drance is one of the pioneer projects for upcoming energy challenges and serves as a model for future pump storage plants. This paper focuses on the planning process and the project execution of interdisciplinary large-scale projects such as Nant de Drance, including project related data handling, communication systems and project handling skills. Furthermore, the paper discusses mining excavation in the context of large scale projects and their regional environmental challenges, e.g. high alpine rock mass on the site of Nant de Drance. PROJECT BACKGROUND Project Overview Nant de Drance is a 900 MW pump storage plant located in the Swiss Alps. To provide such a high energy storage, six turbines (reversible Francis type), each with a capacity of 150 MW, were installed. Due to the efficiency factor of 80% the pump storage plant is able to provide an energy production of 2500 GWh per annum. Construction of the pump storage plant, which has been selected as “Major Tunneling Project of the Year” in 2014 by NCE and ITA-AITES, will be completed over 10 years. Therefore, the project has been divided in six major phases outlined below: - Launch: 2008 - Access Gallery: 2010 – 2012 - Excavation KMA, KTR: 2011 – 2014 - Concreting KMA, KTR: 2014 – 2016 - Installation of HEM equipment: 2014 – 2018 - Tests & entry into service: 2017 – 2018 Figure 1 outlines the single process phases of the project. For the construction of the shafts, galleries and caverns, 1.7 million m³ of metamorphic rock with sedimentary origin (mica schist & paragneiss of the massif „Aiguilles Rouges“) were excavated. A tunnel network with a total length of 15 km was created. The machine cavern measures 194 m long, 32 m wide and 52 m tall."

Jan 1, 2016

By Donald G. Dahle

Project Payette is a conceptual nuclear experiment under the Vela Uniform program intended to further evaluate the mechanism of seismic decoupling. Vela Uniform is a Department of Defense program to improve this country's capability to detect, locate and identify underground nuclear detonations. This program evolved from recommendations of the Panel on Seismic Improve¬ment, (Berkner Panel), an officially appointed group of noted U. S. scientists. This Panel, taking note of difficulties in detecting the differences between some underground nuclear detonations and some earthquakes recommended a program of increased basic research in seismology. The theory of decoupling, Which involves possible reducing of seismic motion resulting from underground explosions by reducing the coupling or physical linkage between the explosion and the geologic environment, was investigated by Dr. Albert latter and his associates at RAND during the late 1950's. The concept has been further investigated theoretically by scientists of the Lawrence Radiation Laboratory and the Sandia Laboratory. The theory has been tested experimentally under Vela Uniform Projects Cowboy, Dribble and Sterling. The Salmon Event of Project Dribble was a tamped (with the explosive in firm contact with the geologic formation) nuclear detonation 2700 feet below ground in the Tatum Salt Dome. Project Payette, if found to be feasible and if authorized for actual execution, would become a decoupled experiment in the same environment.

Jan 1, 1968

By Ronald B. Stone

This paper describes a proposed solution to the problem of mining a 315 foot diameter unsupported sphere at a depth of 2700 feet in a salt dome by conventional mining methods. The proposed solution utilizes many of the varied technologies available to the mining engineer for solving mining and underground construction problems. The following are reviewed in the paper: A. The location of the sphere within the dome as required by construction criteria. B. The relation of the location of the access shafts to the sphere. C. The rock mechanics theory in relation to the salt dome and large size of the excavation. D. The proposed "honeycomb" method of mining which will be a partial answer to rock mechanics stability requirements. E. The equipment which it is recommended be utilized to accomplish the construction. F. The rock mechanics measuring instruments proposed. G. The methods of disposal of the mined salt. Conclusions and areas of further study are outlined in the final statement.

Jan 1, 1968

By Jr. Kermit Allen

A study was conducted for the AEC to determine the feasibility of constructing an unsupported 315 foot diameter spherical cavity at a depth of 2,700 feet in a salt dome. A cavity of this size and shape has never been attempted. It was determined that the three basic essentials for solution mining; adequate salt, fresh water, and a means of brine disposal were available at the Tatum Salt Dome in Lamar County, Mississippi. Assuming a large, unsupported mined opening of the size and at the depth required would remain stable, the most practical method of providing the cavity using solution mining techniques is by use of a movable blanket of air to control the water level to properly shape the cavity while removing the insolubles either with jetting or by conventional mining methods. It is estimated that, using the jetting method of insolubles removal, the cavity can be constructed in 24 months for approximately $7 million. Using conventional mining techniques to remove the insolubles and shape the final cavity, it is estimated that the cavity can be constructed in 36 months for approximately $12.6 million.

Jan 1, 1968

By C. Patrick, T. Combs

The purpose of this paper is to provide a method for analyzing the sequencing of mining production processes and predicting the effects of any planned changes. Included is a description of the development and utilization of a project-scheduling simulation that combines analytical scheduling with stochastic-activity durations. The simulation is demonstrated in two realistic examples: a longwall face-to-face transfer sequence and the effect of varying advance rates on longwall development sections. Statistical data that can provide a basis for more informed production decisions are generated in the form of project activity/path criticality and project-duration distributions. In both examples, a quantitative risk assessment, regarding subjective decisions in underground production sequencing, is presented.

Jan 1, 1996

By Ethan Steward, Kyle Perry

The study investigates the effects of high-velocity impacts of common mine materials on a reinforced mine seal rated to 120 psi. It found that materials propelled during an underground explosion could generate enough stress to crack or damage seals, even with little visible damage. This highlights the need for careful evaluation of mine seals after any impact or high-pressure event.

Aug 1, 2023

By Kyle A. Perry, Ethan A. Steward

The mining of underground coal presents several hazards for miners, including the risk of an explosion fueled by methane gas and coal dust. Methane gas, produced during coal formation, can continuously leak into old workings and build up through its lower explosive limit. Underground coal mines are required to maintain safe conditions, either by ventilating old workings or sealing them off using approved methods. Seals must be designed to withstand instantaneous pressures for a minimum of four seconds. A design strength of at least 50 pounds per square inch (psi) is required for atmospheres monitored and maintained inert, 120 psi for non-inert or not monitored, and greater than 120 psi for special cases. Due to the high cost and testing environment availability, most mine seals are designed through calculations and computer modeling and not subjected to full-scale testing in a representative environment. High pressure is not the only threat that mine seals may be exposed to. During an underground explosion, pressure waves and gas expansion may propel common mine items and objects to a high velocity, generating enough energy to damage mine seals and reduce their strength. Damaged mine seals may fail to contain their rated pressure, allow high pressure gas and fumes to vent through the seal during an explosion, or allow gasses to leak through the seal later after an explosion has occurred. This paper examines the effects of high velocity impacts of common mine materials and items on a reinforced mine seal rated to 120 psi.

Jun 2, 2023

By E. Iasillo, R. R. Carneiro

Independent of the method chosen to forecast production, an accurate method to project metal extraction is needed in order to accommodate leach cycles that exceed leach data on hand and thus be able to accurately forecast production. Metal extraction data must be developed for each ore type identified in the deposit in order to apply the correct rate of leaching when a specific ore is being treated. Curve fitting is used to model the rate of disengagement of metal into the pregnant solution. This paper provides a description of a curve fitting algorithm developed by Mr. John T. Bartlett, inventor of the METSIM™ process simulation program. A methodology is provided by which the metallurgical data developed is evaluated to determine if accurate projections may be made from the data. A criteria has been developed to help determine when a column experiment may be terminated.

Jan 1, 2001