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By V. I. Lakshmanan, R. Roy

"Zinc is the fourth most widely used metal in the world after iron, aluminum and copper. The primary zinc production is through flotation of zinc concentrate, roasting, leaching and electrowinning. Close to 60% of the metal produced is consumed in galvanizing the steel by making a thin layer of zinc coating on the steel surface by hot dip galvanizing. Process Research ORTECH Inc. has developed an efficient energy-saving sustainable technology for the recovery of zinc from secondary sources such as galvanized steel scrap, dross, dusts etc. The process consists of treating the zinc containing scrap in an alkaline solution to remove the zinc and thereby producing a zinc free steel scrap for recycle. The zinc containing leach liquor is subjected to a solvent extraction process to recover value added zinc oxide as the final product. In this paper, important industrial processes for the recycling of zinc including the PRO process will be discussed. BACKGROUNDZinc is the fourth most widely used metal in the world after iron, aluminum and copper. Global refined zinc output increased by 2.7 per cent to 13.16 million tonnes in 2011 and is expected to increase by an additional 2.4 per cent to 13.48 million tonnes in 2012 [1]. The primary zinc production is through flotation of zinc concentrate, roasting, leaching and electrowinning. Close to 60% of the metal produced is consumed in galvanizing steel by making a thin layer of zinc coating on the steel surface by hot dip galvanizing. Other major usages of zinc are in the production of brass and bronze, die casting and zinc-air batteries. The additional demand for zinc could come from its addition to fertilizers to increase crop yield.While the demand for zinc is increasing, many mines are scheduled to close in near future after being depleted of ore. The mines set to close between now and 2015 are Teck Resources’ Red Dog Mine in Alaska, Minmetals’ Century Mine in Australia and Vedanta Resource’s Skorpion Mine in Namibia [1]. The depletion of resources due to continued use and exploitation is becoming a great concern for the zinc industry. As a result, the sustainability of natural resources for continued societal care has become extremely important. Resource conservation and recovery by recycling with minimal environmental impact is a key element for sustainable development. In this paper, important industrial processes for the recycling of zinc including the PRO process are presented."

Jan 1, 2012

By Alain Blouin, Mohamad Sabsabi, Aissa Harhira, Paul Bouchard, Greg Lithgow

"The objective of this study was to demonstrate the application of Laser-Induced Breakdown Spectroscopy (LIBS) to the continuous analysis of online monitoring of Al, Mg, Ni, Mn, Si and Fe in nickel ore limonite and saprolite slurry samples. Analysis was performed on slurry samples in air at atmospheric pressure. Two pure samples of limonite and saprolite were used. Mixtures of the two samples in varying proportions were used to build calibration curves, study the influence of solid/liquid ratio, and evaluate short and long term reproducibility. The LIBS measurement of these elements is independent of the water content (from 70-85%, the range allowed by our setup). Repeatability of the measurement and long term reproducibility (from day-to-day) were below 1.2 % and 2% respectively for all the elements studied in our conditions. The results obtained showed that an industrial LIBS analyzer could provide the chemical composition of the six elements Al, Mg, Ni, Mn, Si and Fe within 1-2 minutes.IntroductionThe metal-producing industry faces the major challenge of increasing productivity, reducing costs, and maximizing benefits from existing equipment. By pyrometallurgy, metal making involves the basic steps of charging the furnace, melting the charge and refining. By hydrometallurgy, the metal refining is carried out through the dissolution of the metal by chemical reaction and electrolysis. During refining either by pyrometallurgy or hydrometallurgy, it is critical that operating parameters be adjusted and controlled so that the chemistry of the melt or the solution is within predetermined limits. Presently, the complete turnaround time for sampling, sample transfer, analysis and communication of the results to the operators is often 30 minutes or more."

Jan 1, 2016

By A. R. Miller, R. A. Stanton, M. J. Male, G. R. Cluff

"The Dubawnt Group consists of continental sedimentary and volcanic rocks which fill structural depressions - Baker Lake Basin, Yathkyed Lake and Angikuni Lake subbasins- whose evolution was controlled by late Aphebian extension, between 1.9-1.8 Ga. Structurally controlled uranium mineralization having the signature U + Mo + Ag + Pb + Cu ± Zn is spatially related to (i) intersecting fault systems that record multiple movements, (ii) chemically reactive lithologies containing sulphide, chlorite or graphite/ carbonaceous matter in the Archean and Aphebian basement complex and as alkaline volcanics of the overlying Dubawnt Group and (iii) areas containing thick successions of basal Dubawnt Group red clastic sediments.The most significant uranium occurrence found to date is the Lac Cinquante deposit, which contains 14 million pounds U3O8 of drill-indicated reserves. Mineralization is hosted in Archean meta-volcanic and metasedimentary rocks of the Henik Group adjacent to the basal Dubawnt unconformity in the northeastern A ngikuni Lake subbasin and occurs as plunging pods in and peripheral to a fractured and brecciated tuffaceous meta-sediment- sulphide+ carbonaceous exhalite. This deposit exhibits many features typified by the classical vein deposit at Beaverlodge, northern Saskatchewan.Epigenetic stratabound U + Cu + Ag ± Mo mineralization, typified by the 74-1E prospect in the eastern Baker Lake Basin, is hosted in thermally altered Kazan redbeds adjacent to alkaline dykes.At the eastern end of the Baker Lake Basin, small prospects having an elemental signature U + Se + Cu + Ag +Au are interpreted as unconformity-related mineralization associated with the Helikian The/on Basin.The Dubawnt Group rocks of the Baker Lake Basin, subbasins and adjacent basement complex contain uranium mineralization of two eras- Late Aphebian and Helikian."

Jan 1, 1986

By Riggin P. R.

"IntroductionIndustrial Relations combines two very important relationships - employee relations and union relations.Employee relations always come into play when people are hired to perform tasks. Because mineral processing plants cannot be operated successfully without people, at least not yet, if they ever will be, employee relations must exist in an operatingplant.If the employees choose to be represented by a union, then a relationship with the union as an institution also comes into play. It is very important to note that unionization does not mean that the employee relationship is replaced by a relationship with the union. The latter is superimposed on the former, but it does not replace it. Similarities and overlaps in the two relationships will be present, some of which are of fundamental importance. Nevertheless, they are two different relationships and the reader should bear this in mind when reviewing those parts of this chapter which discuss unionization, collective bargaining, collective agreements, and work stoppages.These two important relationships, which we have chosen to combine and call industrial relations, have crucial roles to play in the social system which interrelates people performing the necessary tasks involved in the operation and maintenance of a plant. The technological organization - equipment, process layout and so forth - and this social system are interdependent and complementary. This chapter attempts to show that the potential level of effectiveness of both the technological organization and the social system depends on the recognition and nurturing of this nexus between them.Occupational health and safety and training are subjects for another chapter. But, both of these have been critical and longstanding employee relations topics . They are destined to take on added importance in the future. As issues in collective bargaining, they are also attracting increasing attention in all union relations. It is hoped that the reader will not isolate from industrial relations those topics which are being dealt with in another chapter. They are very much a part of it and we cannot refrain from making some reference to them."

Jan 1, 1989

By A. J. Vivyurka

"This is a talk about the experiences that Rio Algom Mines Ltd. has had in the Elliot Lake uranium area trying to make the tailings more compatible with the surrounding environment. To get a better idea of the problem that we are associated with we have to go back to the location. The Elliot Lake uranium area is situated about half way between Sault Ste Marie and Sudbury and is about 20 miles north of Lake Huron. In 1950, uranium was discovered along the north shore of Lake Huron and by 1961 we had up to 9 mines operating in the area. Then the United States Atomic Energy Connnission withdrew their contracts so that at present there are only 2 mines operating. From all the mines that we had operating, we ended up with 7 tailings areas. From these 7 tailings areas we have 5 sites where we have active treatment or rehabilitation. There is the Pronto site where we are treating uranium tailings and copper tailings. There is the Lacnor-Nordic site which is located just out of Ellio Lake. The Milliken-Stanleigh site is in the Crotch Lake area. The Panel tailings is off the north end of Quirke Lake and finally there is the operating property of Rio Algom Mines at Quirke Lake.To understand fully the problem with this rehabilitation we have to look at the constituents of the ore. The ore body is a quartz conglomerate with uraninite and brannerite as the uranium bearing minerals in a fine ground mass of quartz, sericite and pyrite which separates the larger quartz pebbles. The approximate composition of the ore is: 80% quartz, 13% chlorite, 7% pyrite and 0.2% uranium minerals. The processing method also adds a few constituents to the final tailings."

Jan 1, 1975

By J. E. Gill

Introduction During the past summer, detailed geological mapping was extended to cover the entire group of 31 claims owned by Waite-Ackerman-Montgomery Mines, Ltd., and considerable new information was revealed by development and exploratory work underground. These new facts provide a more complete view of the lithology and structure of the area than has heretofore been available. They also necessitate revision of certain interpretations presented last year by Peale (l), and have served to straighten out some of the problems suggested by Porritt (2). The purpose of this paper is to outline in a broad way the relations as now understood and to discuss in detail certain points which should be of interest to members of the Institute. Maps and records by the mine staff have been freely used in arriving at the interpretation presented in the following pages. The writers are especially indebted to Mr. R. V. Porritt, the mine manager, with whom many of the problems touched upon were discussed on the ground and whose intimate knowledge of the geology of the underground workings aided greatly in testing various hypotheses. The writers have profited greatly, also, from close association with Dr. W. F. James during the course of the work. Permission to publish the included data has very kindly been given .by the management.

Jan 1, 1932

By T. M. Waterland

A GREAT deal of work has been done at Britannia during the past three years in improving and standardizing rounds for development headings, and the results obtained have been very gratifying. The round which has recently been adopted as a standard for all drifts and cross-cuts has, in some instances, doubled the average length of break formerly obtained. It has also increased the footage of advance per labour shift and reduced explosives' consumption. At the present time, with a shortage of skilled labour, more control is necessar7 in directing the drilling of rounds. The use of a standard round has been o great assistance to the foremen and shiftbosses. NATURE OF GROUND Most of the ground encountered consists of a moderately silicified chlorite schist, known locally as G.M.S (green-mottled schist). It cannot be termed hard ground, because a three and one-half inch Leyner will drill at an average rate of twelve inches per minute. Due to the abrasive nature of the ground, the gauge of the steel wears rapidly and in most cases one set of steel is needed for each hole. The ground is not 'free breaking and holes must be spaced correctly to obtain a maximum break. DEVELOPMENT OF STANDARD ROUND FOR THREE-SHIFT OPERATION Late in 1940, a development programme was started involving 7,000 feet of drifting, 6 ft. By 7 1/2 ft. In cross-section, in two headings. Plans were drawn up to advance the headings on three shifts. Equipment used in the headings was as follows: D.A.35 Leyner?machines, Eimco Model 12B mucking machines, nine one-ton end-dump cars, one Mancha Little Trammer on the longest heading, 20-pound rail, 4-in. 15 compressed-air line, 15-in. Fan pipe connected to 5 h. P. Coppus fan. Diamond-drill cross-cuts, 16 feet in length, were cut every 250 feet. Switches were installed at these cross-cuts and they served as passing points for the cars. One siding seventy feet in length was cut in each heading at approximately the half-way point. The cycle of operations planned was to muck out, drill, and blast each shift. Previous performance in this type of ground indicated that a daily advance of 12 feet to 14 feet might be made. However, if a better type of round could be developed, an increased daily advance would be possible. A study of the time available for each operation in a net working shift of six and one-half hours indicated that the maximum depth of round that could be mucked, drilled, and blasted each shift would be six and one-half feet. When this maximum depth was decided upon, the next problem was to develop a satisfactory round. Due to ventilation difficulties and to the short net working shift, the whole round had to be blasted at one time. In other words, no blasting of the cut-holes could be done.

Jan 1, 1942

By D. M. Baird

"THE Island of Newfoundland lies on the extreme eastern edge of the continent of North America and at the extreme northeastern end of the Appalachian geological province. Its belonging to the Appalachian province is shown in the geological history of the region and in the rock types and structures.Geosynclinal sedimentation in early and middle Palaeozoic times was interrupted by Taconic and, more profoundly, by Acadian, mountain building activity. Mid-Palaeo-zoic intrusions range from masses of serpentinized ultrabasic rocks to granite batholiths. A Carboniferous overlay of continental and shallow, drying sea types covers the earlier developed complex. Local basins in these times were filled with products of the erosion of tl1e earlier rocks, and, locally, grew the right kind of vegetation to make thin, discontinuons seams and pockets of coal. Post-early Pennsylvanian history is one of erosion and pene-planation with renewal of movement along many of the older fault systems."

Jan 1, 1960

By B. Burke

Magnesium and its alloys are attractive materials for use in automotive and aerospace applications because of the low density and good mechanical properties. However, difficulty in forming magnesium and the limited number of available commercial alloys limit their use. The present paper reviews the efforts to improve the attractiveness of magnesium through non-traditional processing, and presents preliminary results of current work on producing magnesium alloys via powder metallurgy P/M. P/M can be used to alleviate the formability problem through near-net-shape processing, and also allows unique chemical compositions that can lead to new alloys with novel properties. The feasibility of producing magnesium powder metallurgy products utilizing the industrially dominant process of mixed powder blending, uniaxial die compaction and controlled atmosphere sintering was investigated. An alloy composition based on the commercial Mg alloy AZ31 (3% Al, 1% Zn) was used to facilitate comparison to similar wrought products. The optimal processing conditions (compaction pressure, sintering time and temperature, and quenching temperature) were found to maximize sintered density and mechanical properties.

Jan 1, 2007

By Chas Kemsley

NO. 6 shaft at Dome Mines, Limited, is an internal shaft going down vertically from the sixteenth, or 2,000-ft., level to the twenty-ninth, or 4,000-ft., level, with loading station and sump below this. It is located approximately 4,600 feet east of No. 3 shaft, the latter being Dome's main shaft through which ail ore, men, and material are handled. The decision to sink this shaft was made in May, 1935, and work was commenced almost immediately. To reach the site of the new shaft, 3,100 feet of cross-cutting, and 1,400 feet of slashing to widen existing cross-cuts, was necessary. On account of the long haul and the large amount of material to be handled, trolley haulage was decided upon and installed as soon as possible to facilitate the removal of waste rock from the crosscut and other necessary excavations. Figure 1 shows a cross-section of the cross cut and the manner in which the trolley wire is supported and guarded. For hanging each individual cross-piece, two holes are drilled into the roof and filled with snug-fitting wooden plugs. Into these, %-in. ragged hanger bolts arc driven by means of a stoper. The bolts are of various lengths to allow for irregularities in the face of the rock, and they have sufficient thread to permit several inches of adjustment for proper alignment of the cross-pieces. These hangers are spaced at 8-ft. intervals except at the curves, where 5-ft. spacing is used. A 2 in. by 6 in. cedar plank is fastened to the cross-pieces directly over the centre of the track. To this the trolley-wire supports are bolted, and 1 in. by 10 in. cedar boards are nailed on each side to act as guards. Two power-supply cables, one telephone cable, and one .Y2-in. conduit lighting circuit are also supported on the trolley-wire hangers, as shown in Figure 1. A 20-in. ventilating pipe and a 10-in. air line are placed as shown, thus acting as a guard to prevent workmen from walking on the track.

Jan 1, 1938

By R. Daignault et G. O. Allard

The Chibougamau area represents a part of the Abitibi greenstone belt. The rocks constitute a volcanic pile (Roy Group) overlain by a volcano-detritic sequence (Opemisca Group). Three important periods of tectonic deformation have been distinguished. The first one produced folds with north-south horizontal axes. The second one is responsible for the isoclinal east-west folds, and the associated regional schistosity. Reverse faulting contemporaneous with this period of deformation, produced two distincts effects. In some cases the faults cause a repetition of the stratigraphic sequence. Whereas in others the faults truncate second period folds. Domes and basins interference pattern are produced by the superposed effect of Di and D2 deformations. The motion of these two periods would be more or less contemporaneous. The deformation could be generated by rising diapirs of early plutons combined with the progressive formation of troughs by gravitational subsidence of denser strata. The rising diapirs of late granitoid plutons produces a wraparound of the host strata.

Jan 1, 1984

By Walter E. Montgomery

ACCIDENT-PREVENTION work in years gone by has been carried on by many mine managers as a philanthropic movement, but in recent years they have come to realise that Safety is good business and pays tangible dividends. Let us begin with the word itself. We are told that an accident is "any-thing occurring unexpectedly, undesignedly, or without known or assign-able cause'. It is further explained that it is any 'unpleasant or unfortunate occurrence involving injury, loss, suffering, or death", and, finally, "any unintentional or non-essential circumstance". We admit that accidents are unfortunate, unpleasant, unintentional, and they generally happen undesignedly and to a great degree unexpectedly, but to say that they happen "without known or assignable cause" leads us to believe that the word 'accident' is often misused. Would it not be more correct to say that a man suffered a "personal injury"? The word 'accident' in its proper sense implies something over which no one has any control, but when the majority of all so-called accidents are analysed we arrive at the incontestible fact that some act or action, previous or present, was the underlying cause. As long ago as the year 1556 this fact was mentioned by Georgius Agricola, who, in writing a paper on metallurgy, aptly stated, "It remains for me to speak on the ailments and accidents of mines, and of the methods by which they can guard against these, for we should always devote more care to maintaining our health, that we may freely perform the functions of our body, than to making profits". Farther on, Agricola relates in more detail, "Sometimes workmen slipping from ladders into the shafts break their arms, legs, or necks, or fall into the sumps and are drowned; often, indeed, the negligence of the foreman is to blame, for it is his special work both to fix the ladder so firmly to the timbers that they cannot break away, and to cover so securely with planks the sumps at the bottom of the shafts, that the planks cannot be moved nor the men fall into the water; wherefore the foreman must carefully execute his own work. Moreover, he must not set the entrance of the shaft-house toward the north wind, lest in winter the ladders freeze with cold, for when this happens the man's hands become stiff and slipping with cold, and cannot perform their office of holding. The men, too, must be careful that, even if none of these things happen, they do not fall from their own carelessness'.

Jan 1, 1938

By J. H. Crocket, J. Andy Fyon

"All gold deposits within the Tisdale Group are spatially associated with carbonate alteration zones; however, not all carbonate alteration zones are host to gold mineralization.Within the komatiitic and magnesium tholeiitic volcanic rocks at the base of the Tisdale Group, discordant and stratabound carbonate alteration zones occur throughout. The alteration zones consist of a ferroan dolomite - quartz inner assemblage which is enveloped by calcite-quartz and an outer chlorite-rich subzone. Factors which control the distribution of carbonate alteration include joint systems, flow contacts, synvolcanic faults and bulk composition of the host rock.Two environments of carbonate alteration can be recognized: 1) The subsea-floor alteration zones developed within the volcanic rock succession where hydrothermal fluids did not discharge directly onto the sea floor. Insignificant gold production has come from this alteration environment. 2) Seafloor zones, which represent points of hydrothermal fluid discharge into the hydrosphere, are spatially associated with felsic volcanic rock complexes and are host to syngenetic, auriferous cherty dolomite.Carbonatized, magnesium tholeiitic basalts, which are host to the auriferous, cherty dolomite, are enriched in antimony (>0.35 ppm), boron (>30 ppm), gold (>5 ppb) and lithium (> 35 ppm), but are depleted in copper ( < 70 ppm), with respect to carbonatized basalts not associated with gold. Orerelated, altered komatiitic flows can be screened using gold (>5 ppb), lead(> 10 ppm), arsenic(> 70 ppm) and antimony (>1 ppm).The habit, petrographic characteristics and certain geochemical characteristics of the altered volcanic rocks suggest that the hydrothermal fluid was of sea-water origin."

Jan 1, 1982

By H. E. Pawson

"COMMON METHODS OF ELIMINATION: The four methods most frequently used to dispose of cyanide wastes are:1. Oxidation2. Dilution with water or with cyanide free wastes3. Acidification and dilution of resulting gas with air4. Alkaline ChlorinationMost operators practice a combination of the first two methods, allowing oxidation and dilution of cyanide waste in tailings ponds. Then, pond effluent is introduced to a stream for further dilution andoxidation which is expected to take care of the cyanide. This method oftreatment does work to a certain degree. Atmospheric oxidation in tailings ponds and in receiving streams chemically breaks down the cyanide radical to form carbon dioxide and nitrogen.2(CN) + 202 2 CO2 + N2The monetary advantage to this method is obvious to the operator but too frequently though, climatic conditions are ignored. Length of winter, and reduced flow of the receiving stream in summer, adversely restricts the result of this combined method. For those of us who rely mainly on dilution it would be wise to remember that 70 million pounds of water are required to dispose of one pound of sodium cyanide (1).The third method outlined involves addition of acid in a closed vessel and venting resulting gas to atmosphere with or without air dilution by mechanical means. Cost, safety and some form of secondary treatment to complete destruction of cyanide remaining in the solution usually make this method prohibitive.The alkaline chlorination method is the one most commonly accepted for treating cyanide bearing wastes since it is felt that cyanide is completely eliminated in this manner."

Jan 1, 1973

By R. D. Brown

"Taxation tends to be a depressing subject. Taxes are unfair, taxes are too high and, above all, taxes are too complicated.In a recent address to the Canadian Tax Foundation, the author discussed in a rather more lighthearted way the possible causes of the complexity of the present Canadian taxation system. In order to provide an element of relief in this series of articles on taxation matters, extracts from these remarks are quoted below :"

Jan 1, 1976

By E. Benguerel, G. Monteith, L. Centomo, S. Pelletier

In early 2007, it became apparent that with changing concentrate feeds, the magnesium (Mg) load projected for CEZinc starting in 2009 and beyond would quadruple and overwhelm the current Mg process bleed capacity. A project was started, following design for six sigma (DFSS) standards, to select both the optimal process and to evaluate its target capacity for the Mg bleed circuit. The economic and process risks of under or over-designing while Mg reduction efforts were underway at the mines also needed to be evaluated. This paper describes the project methodology, the impact on the plant, and some potential optimizations for CEZinc&apos;s basic zinc sulphate (BZS) Mg bleed process.

Jan 1, 2008

By A. Taylor, E. Thorn Corthay, R. Storey

In response to requests from its stakeholders, the International Standards Organisation is engaged in development of an international standard for Energy Management Systems (EnMS) which will become "ISO 50001". This new standard will build on the successes of both the EN16001 EnMS standard that has been used by dozens of European companies, as well as the ANSI/MSE 2000:2008 EnMS standard that is currently being used in several pilot projects in the USA and Ontario. This paper provides an overview of the key points of the EnMS standards, and describes how they can be used to drive sustainable energy reductions in the metallurgy industry.

Jan 1, 2010

By E. Dernedde

A few studies have suggested that the rate of adsorption of hydrogen fluoride on smelter grade alumina is determined by kinetic factors. However, no performance equation for dry scrubbers has appeared in the literature so far. Experimental data from a pilot dry scrubber with co-current flow were compared with results of kinetic models of adsorption, film diffusion and pore diffusion. The pore diffusion model was deemed the most appropriate. It was transformed into a performance equation for steady-state operations of dry scrubbers by the inclusion of the alumina recirculation. Operating results of industrial dry scrubbers with co-current flow were successfully evaluated by means of the performance equation. The average fluoride content of the alumina was also estimated by using the pore diffusion model.

Jan 1, 2011

By A. J. Paul Laprairie

"ADVANCE planning of mining methods, from the first development openings to stope layout and pillar recovery, has long been accepted as a normal method of operating a mine. Recently, mine managers have become increasingly aware that advance planning of cost and accounting controls can also be considered a normal method of operation. The use of such controls is wide-spread in manufacturing industries. In mining, the gold mines of South Africa have pioneered, with marked success, in this field and have been closely associated with most of the research and field work in accounting control. Canadian mine managers are also beginning to realize the advantages of using planned costs. The control procedures which subsequently have been introduced at various mines have come to be known by such names as ""Responsibility Costing"" or Budgetary Control"".Budgetary control, the term used in this paper, is based on the concept of decentralized authority with centralized control. ;The control is achieved by measuring results against yardsticks which are in the form of budgets or standards. Bud-gets are made for the future activities of each possible operation as planned by the department head, and attention is directed to variations from this plan. Furthermore, the control process charges to each operation only those costs which are incurred directly for that operation, and which can be controlled by the person in charge. Thus, budgetary control relates results to the officials responsible for those results. Expenditures are analyzed according to the organizational structure of the mine and the people who run it, and not according to production processes."

Jan 1, 1960

By J. G. Thomson

Development of the Canadian North, a subject of growing national interest, must in part await the development of better forms of trans-port. The estimated 500,000 square miles of muskeg terrain in the north combined with the" scarcity of roads make essential the early development of special purpose muskeg vehicles. Good progress has been made in the last eleven years in classifying muskeg and some progress has been made in determining its mechanical properties. Limited travel is now possible through the use of special purpose tracked vehicles which have been built without adequate design data. A program to provide data which can be used to optimize muskeg vehicle designs began in 1957. The results of the second phase of this pro-gram are presented in this report. It is shown that vehicle performance in muskeg is directly related to the mechanical properties of the muskeg. Further, it is shown that good de-sign practice for tracked vehicles expected to operate in snow, sand, soft clays and loams is also good practice for muskeg vehicles. All indications are that muskeg mechanics is properly a part of conventional soil mechanics.

Jan 1, 1961