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By Peter A. Hacquebard

"Two continuous coal zones occurring in a 2500f t (762 m) thick section of the Upper Carboniferous Pictou Group (Westphalian C and D) have been encountered in five offshore wells drilled f or oil and gas in the Gulf of St. Lawrence. They correlate, by means of fossil spores, with thick coals of the Mabou and Inverness coalfields situated at the eastern margin of the Basin. Therefore, the presence of a large submarine coalfield of at least 18000 sq mi. (46 620 km'] is indicated. This compares with an estimated size of 14 000 sq mi. (36260 km' ) for the Sydney Coal Basin.Accessibility is provided only by the small onshore parts of the Mabou and Inverness fields, because farther offshore the coals lie too deep to be mined (below 4 OOO f t ([ 219 m)).Two near-shore coal exploration wells indicate that at Mabou Mines the younger Inverness coals occur at a mineable depth to at least 5 km from land. A structure contour map of this area shows a reserve of 125 million tons in two Inverness equivalent seams that are 8.5 ft (2.6 m) and 4.5 ft (f.4 m) thick. The Mabou coals, however, reach too great a depth close to shore to possess mineable resources.A structure contour map of the Inverness submarine area, based on mine data and one off shore seismic profile, indicates inferred mineable resources of 160 million tons, in two seams that are 7ft (2.1 m) and 4.5 ft (f.4 m) thick . A detailed deep seismic survey will be necessary to substantiate the structure and resource estimates"",Maceral and coal quality percentage diagrams of five column samples of these seams (the 7 Foot and 13 Foot Seams of Inverness Equivalents) show a bright banded coal, high in reactive macerals, which will produce a weak coke unsuitable f or metallurgical purposes. A thermal coal with a rank of H. V. ""B"" Bituminous (0.64% Ro) is present, averaging 12000 btu llb (6 660 kcai/kg), 10% ash and 6% sulphur, of which 60 to 80% is derived from pyrite.Microlithotype profiles of the major Mabou and Inverness coals show characteristic successions that can be used f or seam identification and proved valuable f or structural interpretations.The time of faulting in the major fracture zone on the eastern margin of the Gulf of St. Lawrence Basin has been deduced from coal rank variations. It occurred in pos tPermian, probably Early Triassic time."

Jan 1, 1986

By C. L. Reichardt

"Pressure exerted on gold producers by regulators, project financiers, and civil society in the wake of the Baia Mare tailings spill in Romania during 2000 prompted most responsible gold companies to sign up to the International Cyanide Management Code for the Manufacture, Transport, and Use of Cyanide in the Production of Gold (the Code). The Code stipulates a ‘cradle to grave’ approach more comprehensive than that applied to any other mining reagent and poses particular challenges for operators who use cyanide-bearing tailings for backfill. This paper examine some of the challenges for Code compliance facing deep underground gold mines that employ backfill technology, most particularly the requirement to demonstrate that the potential migration of cyanide (and its degradation products) from emplaced backfill will not have an unacceptable impact on worker health and safety or on the receiving environment, either during mine life or after closure.Although the Code only contains a single reference to backfill, more careful consideration confirms that most sections of the Code that deal with tailings management are potentially applicable to mines where tailings material is used for backfill. Certain principles of the Code also pertain to aspects of operations, worker safety, emergency response, training, and dialogue with stakeholders relating to backfilling practice.For gold mines of the Far West Rand, the most significant cyanide-related risks associated with backfill operations relate to worker exposure to cyanide-bearing seepage and HCN gas. There is potential for seepage of cyanide-bearing water from backfill to compromise the beneficial use of surface and groundwater, and thus impact on downstream users and ecosystems. However, the extreme depth of mining and the specific geological and hydrological controls on the Far West Rand suggest that the potential environmental risks associated with backfill are likely to be considerably less significant than the cyanide-related risks to the workforce."

Jan 1, 2007

By W. M. Goodwin

"IntroductionIN THE preceding paper we have learned about Canada's resources of metallurgical coal. There is an adequate amount in Nova Scotia, a very large reserve on the eastern flank of the Rocky mountains, and a strictly limited supply on the Pacific coast. Added to these is an unknown quantity of coking coal in the Peace River district, at present rather isolated but possibly capable of industrial development in the future.The chief use of metallurgical coal is to make iron and steel. For this, an adequate supply of iron ore is required. So we should now scan the Canadian supply of iron ore, the possibility of its increasing use at home, and the probable markets abroad.Trade in iron ore tends to be international, as is the case with many other raw materials. The present tendency with iron and steel, in contrast, is to keep its manufacture within national boundaries, and there is no evidence that this will change much in the years to come. We should keep these two points clearly in mind when considering the disposal of iron ore from Canadian mines. We should remember, also, that the modern blast furnace and steel plant has such a large output that a correspondingly large population, reasonably compact, is needed to consume its products.Large Ore Supply in East, Small in WestCanada has now four major iron ore fields, well situated to serve adequately the eastern half of the country. Wabana .and Labrador are well placed to serve overseas markets and plants on the eastern seaboard and eastern interior of the United States and Canada."

Jan 1, 1952

By Subrata Dutta

Sindesar Khurd Mine is situated in Rajasthan, India, and operated by Hindustan Zinc Ltd, under Vedanta Group. The base metal mine is high in reserves of Lead, Zinc and silver and has been producing since 2007 with initial production of 0.3 mtpa. Recently the mine has gained prominence as a base metal underground mine in introduction of latest mining techniques and achieving high production at lowest costs. The promising Lead-Zinc reserves of Sindesar Khurd Mine (SKM) and high-tech exploration adopted by Hindustan Zinc Ltd (HZL), (Vedanta Group), raising the reserves and resources from a meager 9 Mt (1997) to 81 Mt (2012), has prompted HZL management to ramp up the mine production from 0.3 mtpa (2006-07) to 2 mtpa by 2013-14 with ambitious plans to reach 3.5mtpa subsequently (presently largest underground metal mine in India). The complete trackless system underground mine, recently equipped with latest leaky feeder communication system (unique in India), utilize modern drilling, mucking and hauling equipment aided with various utility/service vehicles. Excavation optimization and quality recovery maximization from the open and post filled stoping methods, continual expert analysis and feedback from International consultants like AMC (Australia) and SRK (UK), and involvement of renowned bodies in management excellence, have lead the mine towards highest productivity and lowest mine operating cost, earning the mine a prominent place in the global base metal industry. The paper deals with how the various challenges in mine planning and designing, mine development, operator skill, equipment introduction and maintenance, expertise availability, provide training and exposure to officials, prompt and effective communication/service, control of ground vibrations, maintain ventilation standards etc are faced in attaining high operational excellence and thus attain a record mine output/man shift (OMS) of 14 ton/man shift with targets to reach 20 ton/man /shift. Scientific designing using 2D/3D numerical mine-modeling techniques, faster stope sequencing with introduction of paste filling ( first time in India),latest leaky feeder communication system, control ground vibration to stringent standards using electronic delay system, faster raising techniques using raise borers to enhance development and ventilation, cavity scanners to monitor large stope voids, fast shaft sinking at 100 m/month(Chinese expertise) and maintaining adequate ventilation with close software monitoring are some of the highlights discussed in the paper towards achieving the targets.

Aug 1, 2013

By C. G. Williams

IN preparing this paper on Canadian mine taxation, there has been no attempt to detail the requirements of the various taxing bodies; but rather to consider the matter from the standpoint of its underlying principles and give a general idea of the methods adopted. I have added an Appendix setting forth the principal features of the various Acts, which should be used for general reference only, since new rulings alter minor details from time to time. In current legislation, many important points are left to the discretion of the Ministers and their deputies. We are, indeed, fortunate in having in Canada an able and conscientious body of permanent officials, who bring a sense of justice and courtesy to their work which is most commendable, and which has done much to simplify the working out of general problems. The production of metals may rightly be deemed a form of manufacture, but differs from the average manufacturing business in three important respects: (1) In its early stages, it is wholly speculative, since it is impossible to make any definite appraisal of value or possibilities. (2) The principal asset of any mine, i.e., the ore in the ground, is a wasting asset, and is irreplaceable. (3) Any additional burden by way of taxation cannot be passed on to the public but must be borne entirely by the producer. Having regard to the first of these differences, it is apparent that, since the risk of loss is great, the reward in case of success must be correspondingly great. This fact seems to be constantly overlooked by those who regard the all too few outstanding successes in Canadian mining history as fit prey for predatory legislation. As an illustration of the speculative nature of early mining development, let us consider the Province of Ontario-and I take this illustration simply because I am more familiar with conditions there, and not because I believe it differs greatly from any other province. From 1907 to 1933, 165,243 claims were staked and recorded, from which 43 mines were developed which paid one or more dividends. There was, of course, some duplication through re-staking; also, on some claims very little work was done, and most mines have more than one claim. But, since staking and recording cost real money and effort, each of these claims must have been considered to have had merit.

Jan 1, 1935

By P. J. Sylvester, D. H. C. Wilton, R. I. Wheeler, M. A. E. Huminick, D. Evans-Lamswood

"Abstract — Systematic characterization of the mineralogy of massive sulfide ore deposits can provide valuable insights into ore genesis and metallurgical processing that would not be apparent otherwise. We describe a method wherein (1) normative mineral abundances are calculated from whole-rock chemical assays using an algorithm, (2) the results are cast in block models, (3) the results are then verified with automated image analysis of a subset of samples prepared as grain mounts by backscattered electron imaging and X-ray mapping on a scanning electron microscope, and (4) those verified results are integrated with textural data determined by optical microscopy.The technique is applied to the magmatic Ni-Cu-Co sulfides of the Ovoid orebody, based on geochemical assays of 3175 whole-rock samples. Three principal ore zones are defined in the Ovoid. Type I ore occurs in the center of the deposit; it is magnetite-rich and pyrrhotite-poor with intermediate contents of pentlandite and chalcopyrite. Type II ore surrounds Type I ore and is pentlanditechalcopyrite- rich with intermediate contents of pyrrhotite and magnetite. Type III ore occurs at the base and along the outer periphery of the northern part of the orebody; it is pyrrhotite-rich and chalcopyrite- poor with an intermediate content of pentlandite, and a low-to-intermediate content of magnetite."

Jan 1, 2012

By Stephen B. Cheeseman

The quantity of data available and the rate at which we access such data are rapidly increasing. Electronic data capture systems, fleet management systems and a host of other technological advancements have created a constant stream of real-time, tactical data. However, are we taking advantage of this data? Are we converting data into useful information to aid in efficient decision-making? Mining operations are struggling with ?information overload?, finding it difficult to extract the benefits from vast stores of data. Without the necessary tools to facilitate a data filtering and information reporting process, most operations revert to old practises such as re-entering data into multiple spreadsheet reports. As a result, the ability to make effective use of data still eludes many mining operations. Some operations have taken audacious steps to rectify this situation. The De Beers Venetia mine in South Africa has implemented an integrated mining information technology solution that transforms their data into practical, usable information allowing staff and management to make decisions that improve efficiencies and reduce costs. In the absence of quantitative justification or ROI, De Beers took a risk in implementing change. Today, they are realising the benefits. This paper will unearth the information technology issues that surfaced during the Venetia implementation, then identify the benefits De Beers has obtained from deploying an integrated mining information technology solution at the Venetia mine.

May 1, 2002

By C. M. Offenhauer

Abstract Zirconium markedly affects the formation of graphite in cast iron and may promote the formation of normal flake gaphite, fine flakes of eutectiform graphite, or spheroid nodular graphite, according to the composition of the Iron and the amount of the zirconium addition. Usually, it is employed in the form of a complex addition agent in order to facilitate its introduction and to guide its effect. The reported applications of zirconium as an inoculant for the production of pearlitic high-strength cast iron indicates that it is most effective as a silicon-manganese-zirconium alloy. Added in this form it reduces chill and minimizes zones of ferrite and eutectiform graphite. In low-sulphur cast iron, zirconium in amounts greater than 0.10 per cent tends to promote the development of eutectiform graphite. These irons are characterized by freedom from primary cementite or normal flake graphite and exhibit very little tendency to shrinkage on solidification. In hyper-eutectic low-sulphur cast iron, zirconium causes the formation of a partially nodular graphite structure. A combination of magnesium with silicon-zirconium alloy was found to produce completely nodular graphite structures without the hazards associated with the addition of elemental magnesium.

Jan 1, 1949

By G. E. Agar, W. B. Kipkie, R. A. Tenbergen

"This paper describes the successful pilot plant testing of a flowsheet, developed at INCO Ltd.'s J.Roy Gordon Research Laboratory (JRGRL), for improved separation of the constituent minerals in a bulk copper nickel concentrate.The flowsheet utilized the fact that xanthate concentration on the mineral surfaces is the most important variable affecting the high lime separation and that reduction of the xanthate concentration could be effected by an oxidative conditioning stage.When the adsorbed xanthate was reduced to a suitably low level, chalcopyrite and pyrrhotite could be floated to leave a high grade nickel concentrate as the residue. Sodium cyanide was added to the froth product to depress pyrrhotite and any remaining pentlandite. The temporary depression of chalcopyrite by the sodium cyanide was overcome by introducing a conditioning step following cyanide addition. The advantages of the flowsheet; improved copper-nickel separation, operation without heating of the pulp, production of both high grade nickel concentrate ( 29. 5% Ni, . 26% Cu) and copper concentrate ( <O. 5% Ni, 30% Cu) were all realized."

Jan 1, 1984

By C L. Briend, O&apos

This paper presents the main features of coal mining in Japan, as determined by the author while attending the International Coal Conference in October of 1963. The general economy of the country is considered, and the requirements for coking coal are outlined. Statistics and comments on production and consumption are then given, with accompanying cost figures, and the characteristics of Japanese coal mining are compared with those of Canada. Mining methods and underground transportation are covered, with emphasis on undersea mining. Finally, a description is given of a visit to the Miike colliery, the largest in Japan. I T was my privilege to attend the International Coal Conference held in Tokyo in October, 1963, to meet many prominent members of the Japan Coal Association and to visit one of the major coal fields. This is probably the reason why I was asked to present this review of the coal situation in Japan. In doing so, it must be pointed out that I am not an expert in coal mining, that my

Jan 1, 1965

By Michael Moats, Adirek Janwong

The use of cylinder electrowinning cells, such as emew® technology, for the recovery of silver from primary and secondary sources has been growing. In this study, common operating parameters used in silver electrowinning were evaluated for recycling applications. Silver powders were produced from an industrial solution in a laboratory scale emew® cell. A design of experiments was employed to evaluate the effects of HNO3 concentration, iron concentration, current density and solution flow rate on current efficiency, particle size, bulk density, and crystallographic orientation. Current efficiency was affected by each parameter with increasing HNO3 concentration having a strong negative effect, increasing iron concentration and current density having moderate negative effects and increasing flow rate having a positive effect over the ranges examined. Finer particles were produced with increasing current density and decreasing flow rate. Bulk density increased when HNO3 concentration increased. The crystallographic orientation of all powders was dominated by the (111) plane. Increasing flow rate decreased the relative intensity of (200) direction. Based on these observations, silver electrowinning in cylindrical cells can operate at high current efficiency and produce larger powders at low HNO3 concentration, low iron concentration, low current density and high flow rate.

Jan 1, 2014

"The Val d&apos;Or Division now comprises the Lucien C. Beliveau Mine and Concentrator (formerly the Pascalis, described below) and the Chimo Mine. Cambior acquired an initial 50% interest in the Chimo Mine in May 1989 and the remaining 50% in April 1990. Cambior&apos;s share of 1989 production was 2121 ounces; the company expects to net 23 750 ounces from Chimo in 1990. Pascalis MineUPDATERenamed the Lucien C. Beliveau Mine at its official inauguration in September 1989, the mine is exceeding forecasts, producing over 11 500 ounces of gold in the first half of 1990. Cambior expects 1990 production to total 34 000 ounces.IntroductionThe Pascalis Mine is located 16 miles east o f Val d&apos;Or, Quebec, and is accessible by a three mile gravel road off highway 117 (Fig. I).The property is wholly owned by Cambior.The Pascalis gold deposit consists o f a sub-vertical diorite dyke 1000 ft long by 30 ft wide containing quartz and tourmaline veins with inclusions of pyrite and native gold . Three vein systems ca n be seen in the deposit , the most important being tensile veins oriented at a right angle to the direction of the dyke and inclined at 40 degrees. These overlapping veins vary in thickness from 4 in. to 40 in. and occur at intervals of six to ten ft. The deposit is, therefore, very difficult to evaluate; a complete evaluation would require drifts over the whole width of the dyke combined with relatively short drill holes (Fig . 2)."

Jan 1, 1990

By Clifford S. Gibson

THE Workmen&apos;s Compensation Ace defines Silicosis as "a fibrocic condition of the lungs caused by the inhalation of silica dust sufficient co produce a lessened capacity for work". This fibrocic condition muse exhibit a specific appearance in the X-ray picture of the chest-an appearance which is not characteristic of several lung conditions which can cause lessened capacity for work and which are not due co silicosis. The layman is sufficiently familiar with this subject co know chat, as far as our knowledge goes, quartz is one of the principal objectionable factors in the production of this condition. He should also know that silicosis respects neither geographical nor industrial boundaries. It is as much a factor in some industrial processes (e.g. foundry work, sandblasting) as it is in mines handling ores containing quartz. Its development co a recognizable stage is usually a matter of many years. As yet, its cure is unknown. Its prevention is possible in varying degrees. The layman should also know that the development of fibrosis may be accelerated by breathing in, or living in, any atmosphere containing dust. Few normal adults, particularly those above a certain age, have clear lungs, and fibrosis in varying degrees is noted in the farmer, the steel worker, the clerk, and many others in varied occupations. It is not restricted to miners. Medical and industrial journals, and at times the press, are crammed with data pertaining to this subject, much of which is misinformation. This is particularly true of certain !laces where the preventive and compensation measures for the good o those earning their livelihood in an industry in which silicosis may be contracted are not so far advanced as in our own Province. A great many of these publishings are alarming to the layman. They leave him with the impression that he is taking his life in his hands if he elects to work underground, particularly in a gold mine-that he has at once sold his heritage of health and chat sooner or later he will succumb to the ravages of this ailment. Nothing could be farther from the truth. Actually, under present conditions in Ontario mines, a very small percentage of the men employed ever become impaired by silicosis to the extent chat they must withdraw from the industry. I propose to tell you briefly something of this subject as it affects our mines.

Jan 1, 1937

By Balmer Neilly

In these days of arrested prosperity, when patience is tried and the future but dimly outlined, Canada&apos;s gold mining industry stands out as a beacon light shedding its rays of hope and confidence and demonstrating that there is still one product unaffected by Customs barriers and eagerly sought by all the people of the world. Some other forms of industry have hesitated and side-stepped. Some have cried for help, and in spite of public assistance, generously extended, they are still unable to demonstrate definitely their ability to resume the onward march. But gold mining has never hesitated. As an industry, it has bad an unique experience. When prices are high and conditions are generally referred to as prosperous, this industry is adversely affected. The cost of production goes up; profits are diminished; public sympathy is lacking; and, thrown upon its own resources, the industry tightens up its belt and throws its whole energy into an effort to improve operating conditions, and offset high prices by increased efficiency. When, in due course, depression follows inflation and prices ebb, the gold miner, through necessity, finds himself physically and mentally prepared to meet the situation.

Jan 1, 1932

By Robert Maquil, Gilles Didier, Walter Steiner

"The 1580 m long dual-tube motorway tunnel Markusberg near Schengen, Luxembourg experiences strong swelling phenomena in each tube related to a 35 m wide diagonally crossing rock layer, some150 to 200m from the east portals. Overburden over the roadway is 26 to 30 meters. Tunnel construction started in 1998 and the tunnel was opened in 2003. The tunnel was driven downgrade from the West, the heave phenomenon started to occur as the tunnel approached completion. No indications of the presence of anhydrite and dissolved sulphates were known prior to tunnelling. Water samples had been taken from the beginning of construction and the concentration of anions and cat ions determined. Sulfate content was substantial, in one well it reached 22 mg/l, this high concentration requires the presence of other ions, in particular sodium and chlorine. Based on the knowledge at the time of construction heaving ground was removed from the tunnel invert and a free space was left below the roadway that is covered by a transversely spanned slab. In addition a series of posttensioned tiebacks were installed below the sidewalls. The void left in 2003 was 1.7m high and closed to less than 0.5 meters in 2007 then it became necessary to widen the free space. A central trench was dug with a height of about 2.5 meters and the benches were lowered.Level surveying had been carried out since 2002. In 2006 two extensometers were installed, one in the zone of strongest heave, the second at the edge of the swelling zone. The extensometer in the center of the swelling zone indicated heave with an essential constant rate with seasonal variations, the heave is concentrated in layer from 2 to 5 meters that heaved by nearly 300 millimeters within 5 years or 60 mm/year, which equals to approx. 1% extension per year. At the abutments heave rates of 20 mm/year where the support resistance is higher were observed. With data from other case histories a relation of heave rate with support resistance was established. Based on the numerous field observations hypotheses for the complex in-situ swelling processes, involving rock mechanics, mineralogical, soil mechanics and hydrogeological aspects were developed"

Jan 1, 2015

By Sherwin F. Kelly

"THE TITLE I have chosen is certainly not one of those self-explanatory ones. I shall endeavour to make its significance clear during my remarks but, in the hope of minimizing that inevitable exodus which follows a good lunch such as this, I am going to withhold the final key to its meaning until the very last sentence of this talk.Some explanation is due at the beginning, however, so for those of you unfamiliar with Spanish I will explain that casa means house, or home. The casa about which I am going to talk necessitates a wide .and generous interpretation of the word, because I am using it to indicate principally that portion of the North American continent which is the home, in the western hemisphere, of British and American ideals of justice and freedom, the dignity of the individual and his right to exercise private initiative .and engage in private enterprise. In a wider sense, I am including the entire western hemisphere, which may yet stand as the last bulwark of political and industrial democracy.As for the treasures of which I am about to speak, may I remind you that there are no• material treasures but those derived from the earth, and they are derived by one of two processes, -mining and farming. These two fundamental industries are the basis, and the sole material basis, of our welfare, our wealth, our very existence. From farming, whether it be farming of the land. or farming of the sea, we obtain the food to keep us alive, healthy and able to work."

Jan 1, 1955

By Timo Heikkinen

We have read, with great interest, Mr. Crocker&apos;s article on "Recent Trends in Autogenous Grinding," published in the October issue of The Canadian Mining and Metallurgical Bulletin. Referring to our paper, "Two-Stage Autogenous Grinding Investigations at Outokumpu," we can now report that last August we changed to this method at the Keretti concentrator. Prior to the conversion, the Keretti plant (see flow-sheet, Figure 1) had two primary rod mills, 6 ft. in diameter and 12ft. in length, in open circuit, followed by four secondary 9-by 12-ft. pebble grate mills in closed circuit with rake classifiers. Last summer, wl1en the Since August, grinding has been successfully carried out autogenously in two stages, with two mills being employed in the primary stage and four in the secondary. The size of the pebbles in the secondary mills is about the same as earlier -l V: i to 3 inches (Figures 4 and 5). Also, we generally prefer two-stage grinding to single-stage grinding because, in the former,

Jan 1, 1964

By G. F. Carr

"IntroductionFLUORSPAR has been found at several •localities in Newfoundland, but all the commercial deposits discovered to date are in the vicinity of St. Lawrence, a town on the southeast coast. Most of the veins are within six miles of St. Lawrence harbour, and between sea-level and an altitude of 400 feet. The St. Lawrence Corporation of Newfoundland, Limited, and Newfoundland Fluorspar, Limited, a subsidiary of the Aluminum Company of Canada. Limited. are the two producers.With the arrival of 1953, the St. Lawrence area entered upon its twenty-second •consecutive year as a producer of fluorspar. Production has increased more or less steadily during this period, as is shown by the fact that approximately one-half of the total shipments to date have been made during the past six years. Between four and five hundred men are employed by the industry, and more than $1,250,000 was paid out in wages and salaries during 1952. Shipments during that year reached an all-time high of 81,283 tons valued at $2,484,943, compared with 67,925 tons valued at $1,966,477 in 1951 (1).As a result of an agreement made in July, 1952, with the United States Defence Materials Procurement Agency, production of the St. Lawrence Corporation, Limited, and St. Lawrence Fluorspar, Incorporated, an affiliated company, will •be increased by .approximately 50,000 tons of acid-grade fluorspar per year. The contract extends over a period of four years, or until 150,000 tons of acid-grade concentrates have been produced."

Jan 1, 1954

By L. Frost

Physical Conditions Great Britain The physical conditions in the mines investigated in Great Britain are similar to those found in the mines of the Dominion Steel and Coal Corporation, with the important difference that many of the coal seams visited were interspersed by a large number of heavy faults, making the development of a continuous face operation difficult, and in many cases the life of a unit development was exceptionally short, adding to unit cost; but in spite of these difficulties, a great deal has been accomplished in the application of mechanical loading units in a number of the mines in the areas visited. The coal-bearing measures, as in Nova Scotia, consist of shales and sandstones, and in some sections mussel bands overlie the coal seams making roof conditions difficult&apos;. In several mines, the main roof consisted of weak shale bind, being held by a coal roof of varying thickness. This shale bind had a tendency to flow when the coal roof was broken. The floor, in some cases where cutter loaders were operated successfully, consisted of weak, flaky shales with very little resistance and a tendency to disintegrate into powder when broken. The depth of cover under which these mines were operating varied from 250 feet to 2,340 feet, with an average of 1,700 feet. The coal seams varied in height from 3 feet to 8 feet 6 inches, and the gradients from level to 33 per cent. The seams vary in hardness, but all-with the exception of one seam, the &apos;Morrison Busty&apos;- presented a cutting problem similar to that found in Nova Scotia. The structure and cleavage of the coal was well defined and uniform. Some of the seams visited were gassy, ?but the temperature of the workings generally was not in excess of 70°F.

Jan 1, 1948

By W. M. Tupper

Municipal governments recognize the importance of aggregates in the local economy and the need to manage this resource in the interest of the public good. They have encountered problems with regulating the industry and the dichotomy between the urban need and the rural source. They have suffered from a lack of financial benefit, an adequate aggregate inventory, provincial strategy, economic information and public understanding. A provincial strategy for ensuring the availability of aggregate supplies to developing areas of the Province is essential. The Province should also be responsible for licensing, research, technical expertise on rehabilitation, public education and financial assistance. Upper-tier municipalities (regions or counties) should assume responsibility for resource management, including resource availability, demand characteristics, truck routing, phasing of resource development and sequential land-use planning. Area municipalities (towns and townships) can best determine the social and environmental impact of a specific aggregate development proposal and should therefore have the primary responsibility for the location of new pits and quarries. They should also have the authority to supplement provincial regulations concerning operating standards and the phasing and standards of site rehabilitation.

Jan 1, 1978