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By Frank E. Dalton

BACKGROUND OF TARP The first settlement in Chicago in the 1830's was only 0.61 m (2 ft) above the level of Lake Michigan. The area was flat and swampy with local streams and rivers generally flowing to Lake Michigan. Repeated outbreaks of cholera and typhoid fever in the middle and late 1800's led to the reversal of the river system (away from Lake Michigan to the Mississippi River). As a result of this reversal, the Chicagoland area has had to restrict water withdrawals from Lake Michigan and has had to develop and implement water management programs in compliance with orders set down by the Supreme Court of the United States. In order to comply with restricted lake diversion requirements and to compensate for a natural setting which was essentially hostile to human habitation, it has been necessary to embark on the construction of massive public works which include the world's largest water filtration plants, the world's largest wastewater treatment plants and finally the construction of TARP. The rivers and streams in the Chicago area are the headwaters of the Illinois waterway system. These headwaters are heavily polluted from combined sewer overflows of the area. Present pollution control laws require that combined sewer overflows be eliminated so that the rivers and streams can be used by the citizens of Cook, Du Page and Will Counties and other downstream communities. Fifty-three of the older most densely populated communities including the City of Chicago, covering an area of 971 sq km (375 sq miles), are served by combined sewers. Combined sewers carry both raw sewage and stormwater. Because porous ground surfaces have been covered 1815

Jan 1, 1979

By Van Price

Some technical developments of the National Uranium Resource Evaluation Program which are of general application in geochemical exploration are being studied. Results of stream water and suspended and bottom sediment analyses are compared for an area near Williamsport, Pennsylvania. Variations of uranium content of water samples with time in the North Carolina Piedmont are seen to correlate with rainfall. Ground water samples from coastal and piedmont areas were analyzed for helium. All media sampled provide useful information when properly analyzed and interpreted as part of a total geological analysis of an area.

Jan 1, 1979

By Leo Wagner

In relation with the construction of the Sölk power station in Steiermark, Austria, tenders were called in October, 1976, for the construction of the 12-km "Donnersbach collector tunnel" by "Steirische Wasserkraftund Elektrizitäts AG". The specified showed both conventional blast tunneling as well as mechanical excavation with a tunneling machine, diameter 3.55 m. Total construction time from the date of the invitation to tender was given as 4 years. Part of the project was the construction of a concrete circular tunnel lining 20 cm thick. In 1977 the contract was awarded to "Arbeitsgemeinschaft Donnersbach", a joint venture formed by two companies, G. Hinteregger & Söhne, Salzburg, and G. Hinteregger, Bregenz. It provided for the project to be carried out with a tunnel boring machine. GEOLOGICAL DATA The entire tunnel was to be bored through a complex of the garnet mica schist group of the Wölz schists formations. These range from highly quartz-bearing to quartzitic mica schists, with thick, discordantly interstratified beds of marble and dolomite. In the western sector the axis of the collector tunnel intersects the bedding at an angle of 30° to 40°, in the eastern sector the bedding is about

Jan 1, 1979

By R. A. Bergman, P. G. Thornhill

Development of the Falconbridge Ferronickel Process for treatment of lateritic nickel ores began with laboratory work in 1955, the year the Company commenced exploration of its concession in the Dominican Republic. Process development centred on selective reduction originally directed to producing calcines amenable to ammonia leaching, but later found suited to electric smelting. The reduction step of the process was developed in a 25 tpd shaft furnace pilot plant located in the Dominican Republic, to which was later added an electric melting furnace. After almost 3 years of development work on this scale the plant was expanded to 100 tpd for fixing design data for a commercial plant. This took the form of the 30,000 ton per year Nickel Ferro-nickel Complex of Falconbridge Dominicans, which started up in 1971.

Jan 1, 1979

By John T. Gormley, Pressley L. Campbell, Harry L. Crouse

INTRODUCTION This paper summarizes an investigation conducted to determine the relationship, if any, between reported occurrences of abnormal levels of carbon dioxide (C02) gas and the construction of a 2.44meter diameter main sewer tunnel under South Eighty-Fourth Street, West Allis, Milwaukee, Wisconsin. Specific objectives of the study were to determine: (1) the sources of C02, (2) the significance of each C02 source, (3) how C02 could move to areas where it was reported to occur in abnormal concentrations, and (4) what actions could be implemented to eliminate elevated C02 levels associated with the tunneling operation. To accomplish study objectives, expertise from several scientific and engineering disciplines was required including chemistry, geochemistry, microbiology, hydraulics, and hydrology. Pertinent documents were reviewed and field data pertaining to each aspect of the study were collected as required and examined to evaluate existing conditions. Background On or about February 1, 1971, gas with a composition different from normal atmospheric air was reported to enter basements and wells of residences in the vicinity of South Eighty-Fourth Street, West Allis, Wisconsin. Examination of the gas composition revealed that it possessed an elevated concentration of C02 and a depleted concentration of oxygen (02). Public health officials who investigated the appearance of the objectionable gas concluded within reasonable certainty that the elevated C02 concentrations were associated with the tunnel construction under Eighty-Fourth Street.

Jan 1, 1979

By S. K. Kawatra

For efficient control of particle size in a wet grinding circuit, three alternative methods for monitoring pro- duct particle size are available. These methods are based on: 1. Ultrasonic wave absorption. 2. Low-angle forward scattering of a laser beam. 3. Inferential sizing techniques. The relative advantages and disadvantages of each technique are discussed. A particle size monitor can be used on a single grinding line to control the product particle size. To minimize the number of particle size monitors at an operation consisting of many similar grinding lines, a portable multi-stream on-line analyzer can be used. The paper outlines the design and the operational characteristics of the portable multi-stream online analyzer.

Jan 1, 1979

By I. H. Keith

INTRODUCTION The following papers describe the extraction of nickel in the form of ferronickel from the Dominican laterites. The Falconbridge process was developed initially in the Falconbridge Metallurgical Laboratories and subsequently in several successive stages of pilot plant operation in the Dominican Republic. In the course of this work we came to believe that there is advantage in piloting on site. Mining, metallurgical and geo-political considerations all have major impact and that belief has been borne out by commercial plant experience. Lateritic nickel ores differ substantially, even within the same orebody, in their amenability to extraction methods. The Falconbridge process takes account of the heterogeneous nature of the deposit. Three years of geological field exploration led to ten years of process development after it was realised that the then known metallurgical processes would not give economical extraction from the Dominican ores. In addition to establishing the viability of a novel pyrometallurgical approach, it was necessary to verify design parameters for a very considerable scale-up to prototype commercial operation. The plant was eventually constructed within the original estimates of time and cost. Unique features contributing to the technical and commercial success of the project are described. Additionally, some bold extrapolation based on pilot plant work, eventually proved to be quite conservative. The mine is not a conventional open pit operation, but is perhaps better characterised as an earth moving job. Novel application of mobile equipment led to great flexibility in the mine, where operation of several mining fronts is essential to maintaining uniformity of ore feed to the plant. The practical aspects of almost total acceptance of the oversize run-of-mine material through a high-capacity unit,

Jan 1, 1979

By A. S. Ericson, J. H. Corrigan, E. J. Jahnsen

Calcine is transported from the Reduction Plant at 850°C in insulated hopper cars and charged into three rectangular electric melting furnaces each equipped with three - 18.5 MVA transformers. The electrical energy is applied through six in line prebaked carbon electrodes, and slag and metal are tapped at opposite ends of the furnaces on an intermittent basis. The slag, 5000 tonnes per day, is disposed of by a pot train directly to the dump. The ferronickel, 250 tonnes per day, is tapped into 40 tonne capacity ladles in which it is refined in two ASEA-SKF ladle furnace stations. Casting is done over lip at 1520°C in a pig casting machine with stepless speed control at up to 55 tonnes per hour. The ingots are stacked into self palletizing bundles weighing about 1500 kilograms and are strapped and tagged and transported to the seaport, from which the final shipment is made to the world market. The paper describes constructional details and gives information of both normal operation and start-up and shut-down procedures. Consumption figures for refractory, electrodes, electric energy and refining additions are given and metal chemistry is given before and after refining.

Jan 1, 1979

By G. Troly, M. Esterle, B. Pelletier, W. Reibell

In New Caledonia, ultramafic formations occur on 7,000 square kilometers. Weathering of peridotites leads to profiles of alteration and nickel concentrations. Complete profiles are composed of two main groups of horizons: 1. Limonitic, mainly composed of iron hydroxides 2. Saprolitic, partly composed of magnesium and iron silicates Shape and mineralogical composition of saprolitic horizons are chiefly affected by the nature of the bedrock: types of peridotite and their degrees of serpentinization. On the other hand, morphology (plateau, terraces, slopes, piedmont) is an important factor. Ore-bodies are inside saprolites; their outlines are determined by the grade of nickel and tonnage economically mineable. Information about geology, morphology, geochemistry, and mineralogy are given in this paper.

Jan 1, 1979

By Y. T. Auck, M. E. Kukura, L. G. Stevens

At its Technical Development Center in Tucson, Arizona, the UOP Mineral Sciences Division operates a completely integrated pilot plant testing a proprietary process for the extraction of nickel from limonite/saprolite ores. The process is based on the reductive roast- ammonia leach procedure now employed in several plants around the world. The process improvements are such that nickel extractions well above that experienced in these processes are possible, particularly on the more garnieritic/saprolitic ores. This paper will describe the process and the results of process development studies. The data show that pilot plant results confirm those obtained on the smaller laboratory and bench scales of experimentation.

Jan 1, 1979

By R. R. Unterberger

This paper addresses the problem of seeing into rock. We will consider two methods, first to use radar, or electromagnetic wave pulses, to probe into rock ahead of mining and second to use sonar, or sound wave pulses, to probe into rock. Both are non destructive and capable of giving information on hazards ahead of mining. Such hazards might be a borehole full of water possibly leading to a high pressure aquifer somewhere above the mine level, changes in rock type, or the edge or top of a salt dome. Most of the work described in this paper deals with probing through rock salt which we have done successfully to over 2000 meters maximum range. We discuss first the radar probing and then the sonar probing. RADAR PROBING OF ROCK SALT Theory All electrodynamics are based on Maxwell's equations, which are in vector form [D = P (1) •B = 0 (2) aB V x E _ -(3) at aD •x H = J + - (4) at] where D and E are the electric displacement and electric field intensity vectors respectively, B is the magnetic induction or flux density

Jan 1, 1979

By A. S. Astakhov

Working out of the production calendar plans (schedules) at deep mines which provide for the interaction of all kinds of mining operations determining coal output growth and mining and technical indices is a striking example of mining art. However, multi-variant decision making, a sophisticated system of integration, as well as high labour consumption for calculation and graphic operations in calendar planning require the improvement of traditional techniques and the development of new methods for calendar planning of mining operations at deep mines. The following specific aims were pursued in developing a computerized system of calendar planning (scheduling) of mining operations.

Jan 1, 1979

By Thomas R. Kuesel

In traditional construction contracting practice, the owner allocated almost all risks to the contractor, saying in effect, "you deal with all construction problems and all third parties, and don't bother me." In this same tradition, the architect or engineer designed a structure in its finished condition, and if he thought about the construction problems that might be involved in building it, he was careful not to express any opinions on these matters in the contract documents. This feudal attitude fostered two results: 1. Contractors added high contingencies to their bids to cover the costs of risks. 2. Litigation of construction contract claims blossomed. Broadly, the owners lost--the courts reallocated many risks the owners thought they had laid on the contractor. Thoughtful owners and engineers recognized that owners were paying for risks twice --once in bid contingencies and a second time in court. Meanwhile, contractors were not getting rich; they were losing money on delays and disputes, and just about getting even (if they were lucky) in court. And construction law was becoming an increasingly lucrative field--for lawyers. Furthermore, with the growing influx of lawyers onto the construction scene, the owner-contractor-engineer relationship became increasingly an adversary one. The emphasis came to be on culpability rather than capability--who could be held responsible for breaching some contract clause, not who might find a solution to some common problem. This game was played with equal vigor by owners and contractors.

Jan 1, 1979

By Omar Abd el Fattah Ramly, Abdallah Mohamed Sourour

FOREWORD In 1974, the Ministry of Housing and Reconstruction (The Client) which subsequently became the Ministry of Development and New Communities of the Government of the Arab Republic of Egypt assigned responsibility to the Arab Contractors (Osman Ahmed Osman and Company) for the design and construction of the tunnels under the Suez Canal. For this project the Arab Contractors of Cairo and Tarmac International of London formed a joint Venture, called Osmac. Sir William Halcrow and Partners of London are responsible for the design of the Ahmed Hamdi Tunnel as a Sub-Contractor to the Contractor. The advisory consultant of the client is a joint Venture between Tippetts-Abbett-McCarthy-Stratton (TAMS) of New York and Arab Consulting Engineers (ACE) of Cairo. INTRODUCTION A site investigation was carried out between Km 141 and Km 150 Suez Canal chainage to determine the ground conditions relevant to design and construction of a road tunnel under the Suez Canal. A feasibility study included aerial surveying, geological mapping and the drilling of 8 boreholes. Detailed investigation included the drilling of 105 boreholes, sampling, piezometer installation, pumping tests, and the digging of trial pits and trial excavations. In-situ work comprised SPT, permeability tests and dilatometer tests. Laboratory testing included soil classification tests, compaction tests, California Bearing Ratio tests, shear strength determination and oedometer consolidation tests as well as chemical analysis of both soil and ground water. The investigation revealed that the ground conditions at the first proposed El Shatt site (Km 148.5) were not favourable for bored tunnelling, whereas they were more favourable at the southern El Shatt site (Km 150.0).

Jan 1, 1979

By Joaquin Marti, Peter A. Cundall

This paper reports on some recent work in which several schemes were developed to model jointed rock under high stress, with particular reference to the phenomenon of "block motion" observed during dynamic loading of underground structures. Three approaches were made, corresponding to an increasing relative importance of internal block deformations as compared to rigid block movements. The first one uses distinct element method and assumes internally rigid blocks, which can break, repeatedly, whenever an empirical crack criterion is met. In the second approach each block is allowed three degrees of freedom to deform internally. The third approach, still in the development stage, permits arbitrary deformation of all blocks, which are internally decomposed into finite-difference zones and automatically rezoned during slip to preserve the calculation accuracy on joints. The last two schemes allow arbitrary constitutive relations for the intact rock, and all three schemes permit the geometrical arrangement of joints to be arbitrarily complex, in contrast to normal Lagrange, finite-difference programs, which are unsuited to model discontinua.

Jan 1, 1979

By Matthew J. Hrebar

Dragline stripping operations account for over one-half of the U.S. bituminous coal production mined by surface coal mining methods. The dragline is a popular stripping tool because of its flexibility in varying overburden depths and relatively low operating costs per cubic yard of overburden. Because of the relatively high capital costs of the machines and their use as a primary stripping tool, the selection process is an important step in the mine planning procedure.

Jan 1, 1979

By L. Whitby-Costescu

The Shebandowan mine and concentrator, with a capacity of 9072 t/week (10,000 st per week), was opened in 1972 after several years of environmental study and planning. The mine is located in a popular vacation cottage .area about 96 km (60 miles) west of Thunder Bay, Ontario. Undertaken before environmental assessment procedures had become an established requirement, Shebandowan is one of the first Canadian examples of effectively integrating environmental work into overall planning. Although it is an underground mine, many of the environmental considerations are common to open-pit operations, and hence, it provides a case history for the use of all mine planners. Computers can play a part in such studies by simulating the annual production of mine wastes, by on-line polling of environmental sensors and by processing sensor data. Early attention was focused on establishing base-line conditions in a two-year water quality monitoring program. Since production began, water quality monitoring has shown that mining has not caused any significant changes. However, mine drainage disposal arrangements had to be modified in the light of operating experience. There is no townsite associated with the mine, and workers commute from established municipalities. Harmonious relations have been achieved with local cottage residents after their initial fears were dispelled. Plans are ready to begin revegetating the tailings when a sufficient area of dry elevated tailings has been accumulated. Rehabilitation of the land disturbed during development was begun before start-up and was completed during initial operations.

Jan 1, 1979

By John S. Jones, Ralph E. Brown

INTRODUCTION For more than a century, artificial ground freezing has been used for groundwater control and structural support for excavations. Most of the early uses of the freezing method were for sinking deep access shafts for mines and tunnels (1,2,3,4). More recently, ground freezing has increasingly been used for construction of large diameter cofferdams and soft-ground and mixed-face tunnels (5). Although ground freezing has been used in the past-for tunnels, it was invariably used as a last resort measure, where more conventional measures could not be used. The more recent freezing applications, however, have become increasingly cost competitive with more conventional techniques, and are now being included as part of the design concept (6,7,8,9,10,11,12). The purpose of this paper is to describe some of the more recent applications of ground freezing for tunnel construction. The paper begins with a brief description of the most commonly used freezing system, the Poetsch process. Recent tunneling projects utilizing ground freezing for structural support are then discussed. DESCRIPTION OF THE FREEZING METHOD The most commonly used freezing method is the Poetsch process, which was originally developed by F. H. Poetsch in the late 1800's. The system consists of a brine coolant, typically calcium chloride and water. Freezepipes are placed into boreholes or are

Jan 1, 1979

By Bengt L. Stillborg

INTRODUCTION This paper summarizes the result of a two and a half year research program. The objective of the research was to develop a fundamental understanding of the Rib-in-Roc method. Through the development of a new model technology, namely three-dimensional physical models which powerfully exploit the results of dimensional analysis Stillborg, Stephansson and Swan (1), it has been possible to establish the contribution to both permanent and immediate stabilization of a large underground opening pre-reinforced by the Rib-in-Roc method. Using the results from these physical models and earlier work by Stillborg and Stephansson (2) and Åkesson (3), a conceptual synthesis is given in this paper so demonstrating the Rib-in-Roc method to be a practical working system of pre-reinforcement. DESCRIPTION OF THE RIB-IN-ROC METHOD To give the reader an idea of how this method of pre-reinforcement is performed, a short description will be given, Figure 1. Before any full-scale excavation takes place an entry is made in the host rock and rib raises are driven around the proposed opening. These raises are made at a spacing that is dependent upon rock quality; an opening in poor rock needs more ribs per length of opening. As the ribs are driven they are used as a site from which very competent rock bolting can be done. As a rib is excavated it is filled with reinforced concrete. Finally after having in this way reinforced the zone around the proposed opening, (a reinforced arch is formed) the displacements are automatically controlled as the opening is being excavated. Using this method openings with a span of 50-60 meters (160-200 ft) and a height of 60-80 meters (200-260 ft) are likely to be realised.

Jan 1, 1979

By D. W. Niosi

In this chapter, a review is made of the various stages of an exploration program, mineral rights acquisition methods and the partners involved in an agreement, the after- tax cash flow approach using present value discounting principles, the establishment of computerized financial models for assistance during the negotiating stages for a mineral property, and the various evaluation techniques and their specific applications during different phases of an exploration program. A set of examples is shown encompassing the initial target-seeking stages to the ultimate feasibility study stage.

Jan 1, 1979